Preoperative Screening

Selective vs Routine

Abstracts

Routine preoperative testing: a systematic review of the evidence.
Munro J, Booth A, Nicholl J.
School of Health and Related Research, University of Sheffield.
Health Technol Assess 1997;1(12):i-iv; 1-62

OBJECTIVES. To review the available evidence on the value of routine preoperative testing in healthy or asymptomatic adults. To assess the completeness of existing reviews of preoperative testing and how applicable their conclusions are to the UK. To identify areas for further research. HOW THE RESEARCH WAS CONDUCTED. The databases Medline, Embase, Biological Abstracts, Science Citation Index and HealthSTAR were thoroughly searched for relevant articles which were then classified and appraised. The databases of the Centre for Reviews and Dissemination (DARE and NHS Economic Evaluations Database) and the Cochrane Collaboration (the Cochrane Library) were also used to verify the completeness of the search. In this review, 'routine' tests are defined as those ordered for an asymptomatic, apparently healthy individual in the absence of any specific clinical indication, to identify conditions undetected by clinical history and examination. RESEARCH FINDINGS. No controlled trials of the value of the following routine preoperative tests have been published. All available evidence reports the results of case-series. CHEST X-RAY. Few studies allow the outcome of routine chest X-rays to be distinguished from those of indicated chest X-rays, and fewer have gone beyond abnormality yields to examine the impact on clinical management. Findings from routine preoperative chest X-ray are reported as abnormal in 2.5-37.0% of cases, and lead to a change in clinical management in 0-2.1% of patients. The effect on patient outcomes is unknown. Both abnormality yield and impact on patient management rise with age and poorer American Society of Anesthesiologists (ASA) status. The limited evidence on the value of a chest X-ray as a baseline measure suggests that it will be of value in less than 9% of patients. ELECTROCARDIOGRAPHY. The findings from routine preoperative electrocardiograms (ECGs) are abnormal in 4.6-31.7% of cases, and lead to a change of management in 0-2.2% of patients. The effect on patient outcomes is unknown. The proportion of abnormal tests rises with age and worsening ASA status. The predictive power of preoperative ECGs for postoperative cardiac complications in non-cardiopulmonary surgery is weak. There is no evidence to support the value of recording a preoperative ECG as a 'baseline.' HAEMOGLOBIN MEASUREMENT AND BLOOD COUNTS. Routine preoperative measurement shows that the haemoglobin level may be lower than 10-10.5 g/dl in up to 5% of patients, but that it is rarely lower than 9 g/dl. The routine test leads to a change of management in 0.1% to 2.7% of patients. Routine preoperative measurement shows that the platelet count is abnormally low in less than 1.1% of patients, and that platelet count results rarely if ever lead to change in management of patients. Routine preoperative white blood cell count is abnormal in less than 1% of patients, and rarely if ever leads to change in management of patients. TESTS OF HAEMOSTASIS. Abnormalities of bleeding time, prothrombin time and partial thromboplastin time are found in up to 3.8%, 4.8% and 15.6% of routine preoperative tests, respectively. The results of these tests very rarely lead to change in the clinical management of patients. BIOCHEMISTRY. In routine preoperative tests of serum biochemistry, abnormal levels of sodium or potassium are found in up to 1.4% of patients, and abnormal levels of urea or creatinine are found in up to 2.5% of patients. Abnormal levels of glucose are found in up to 5.2% of patients. These abnormalities rarely lead to change in clinical management of patients. URINE TESTING. Routine preoperative urinalysis finds abnormal results in 1-34.1% of patients, and leads to a change of management in 0.1-2.8% of patients. The only abnormality that leads to a change in management of patients is the finding of white blood cells in the urine. There is no good evidence that preoperative abnormal urinalysis is associated with any postoperative complication in non-urinary tract surgery. (ABSTRACT TRUNCATED)

The preoperative bleeding time test lacks clinical benefit: College of American Pathologists' and American Society of Clinical Pathologists' position article.
Peterson P, Hayes TE, Arkin CF, Bovill EG, Fairweather RB, Rock WA Jr, Triplett DA, Brandt JT.
Department of Pathology, Cornell University Medical College, New York, NY, USA.

Arch Surg 1998 Feb;133(2):134-9

The major conclusions of this position article are as follows: (1) In the absence of a history of a bleeding disorder, the bleeding time is not a useful predictor of the risk of hemorrhage associated with surgical procedures. (2) A normal bleeding time does not exclude the possibility of excessive hemorrhage associated with invasive procedures. (3) The bleeding time cannot be used to reliably identify patients who may have recently ingested aspirin or nonsteroidal anti-inflammatory agents or those who have a platelet defect attributable to these drugs. The best preoperative screen to predict bleeding continues to be a carefully conducted clinical history that includes family and previous dental, obstetric, surgical, traumatic injury, transfusion, and drug histories. A history suggesting a possible bleeding disorder may require further evaluation; such an evaluation may include performance of the bleeding time test, as well as a determination of the platelet count, the prothrombin time, and the activated partial thromboplastin time. In the absence of a history of excessive bleeding, the bleeding time fails as a screening test and is, therefore, not indicated as a routine preoperative test.

A prospective evaluation of the efficacy of preoperative coagulation testing.
Rohrer MJ, Michelotti MC, Nahrwold DL.

Department of Surgery, Northwestern University Medical School, Chicago, Illinois 60611.
Ann Surg 1988 Nov;208(5):554-7

The efficacy of routine screening coagulation tests was studied to identify occult coagulopathies in patients prior to elective general and vascular surgery procedures. The efficacy of screening tests was compared to that of indicated tests performed for predefined clinical indications, which were elicited by history and physical examination and a detailed coagulation history questionnaire. Tests were prothrombin time (PT), partial thromboplastin time (PTT), platelet count (PC), and bleeding time (BT). Of 514 screening tests done in the 282 patients, 4.1% were abnormal, but none of them identified a clinically significant coagulopathy. Of the 605 indicated tests, 7.4% were abnormal, and all significant coagulopathies were found in this group. The study shows that preoperative screening tests for coagulopathies not suspected on the basis of detailed clinical information are unnecessary and should not be done. In the authors' institution 46% of screening coagulation tests could be eliminated.

The need for routine pre-operative coagulation screening tests (prothrombin time PT/partial thromboplastin time PTT) for healthy children undergoing elective tonsillectomy and/or adenoidectomy.
Asaf T, Reuveni H, Yermiahu T, Leiberman A, Gurman G, Porat A, Schlaeffer P, Shifra S, Kapelushnik J.
Pediatric Hemato-Oncology Unit, Soroka University Medical Center, P.O. Box 151, 84101, Beer-Sheva, Israel

Int J Pediatr Otorhinolaryngol 2001 Dec 1;61(3):217-22

In some medical centers, the routine pre-operative evaluation of healthy children undergoing elective tonsillectomy and/or adenoidectomy (T and A) includes coagulation screening tests (PT, prothrombin Time; PTT, partial thromboplastin time; and INR, international normalized ratio). In this retrospective study, we determined whether there is a positive correlation between prolonged PT/PTT/INR tests in healthy children, with no prior medical history of coagulation problems, and bleeding during surgery and/or bleeding in the month following surgery. We reviewed the records of 416 elective T and A surgeries performed at the Soroka University Medical Center in Beer-Sheva, Israel, over the course of 1999. One hundred and twenty-one (29.1%) patients had preoperative prolonged PT values but only four (3.3%) of these patients experienced light bleeding during surgery. Seven (5.8%) of the 121 patients with prolonged PT tests experienced bleeding episodes during the 1st month subsequent to the surgery. Of the 65 (15.6%) patients who had prolonged pre-operative INR values, only three (4.6%) experienced light bleeding during surgery. Two (3.1%) patients with prolonged INR values experienced light bleeding during the 1st month subsequent to surgery. Sixty-one (14.7%) patients had prolonged first preoperative PTT values, only five of whom (8.2%) experienced light bleeding during surgery. Two (3.3%) of the 61 with prolonged PTT values experienced light bleeding during the 1st month subsequent to surgery. We therefore concluded that pre-operative coagulation screening tests provide low sensitivity and low bleeding predictive value. As such, routine coagulation tests before T &A are not indicated unless a medical history of bleeding tendency is suspected.

Routine prothrombin time determination before elective gynecologic operations.
Aghajanian A, Grimes DA.
Department of Obstetrics and Gynecology, University of Southern California School of Medicine, Women's Hospital, Los Angeles.
Obstet Gynecol 1991 Nov;78(5 Pt 1):837-9

The prothrombin time (PT) test is routinely ordered to identify unsuspected bleeding disorders in patients before elective operations. We evaluated the usefulness of screening PT tests before elective gynecologic operations over a 6-month period at Women's Hospital in Los Angeles, California. Of 1546 patients, 1516 (98.1%) had normal test results. Charts of 25 of the 30 patients with abnormal values were available for review: 20 did not benefit from the test results, and five had indications for coagulation testing on history or physical examination. In the absence of specific indications, routine preoperative PT testing before elective gynecologic operations does not contribute to patient care and should be eliminated.

CATARACT SURGERY

Are routine preoperative medical tests needed with cataract surgery?
Lira RP, Nascimento MA, Moreira-Filho DC, Kara-Jose N, Arieta CE.
State University of Campinas-UNICAMP, Department of Ophthalmology, Campinas, Sao Paulo, Brazil. rpclira@uol.com.br

Rev Panam Salud Publica 2001 Jul;10(1):13-7

OBJECTIVE: The objective of this study was to investigate whether routine medical testing before cataract surgery reduces the rate of complications during the perioperative period in adults. METHODS: The study was carried out in an academic medical center in Brazil, between 10 February 2000 and 10 January 2001. The scheduled cataract operations were randomly assigned to one of two groups: 1) to be preceded by routine testing (the "routine-testing group") or 2) not to be preceded by routine medical testing (the "selective-testing group"). If the patient was assigned to the selective-testing group, it was requested that no preoperative testing be performed unless the patient presented with a new or worsening medical problem that would warrant medical evaluation with testing. In the case of patients assigned to the routine-testing group, three tests were requested: a 12-lead electrocardiogram, a complete blood count, and measurements of serum glucose. RESULTS: The sample of 1,025 patients scheduled to undergo cataract surgery was comprised of 512 assigned to the routine-testing group and of 513 assigned to the selective-testing group. The two groups had similar proportions of operations canceled and not subsequently rescheduled, 2% in each group. The cumulative rate of medical events was similar in the two groups, 9.6% in the routine-testing group and 9.7% in the selective-testing group (P = 0.923). The types of medical events were also similar in both groups. DISCUSSION: The results of this study suggest that routine medical testing before cataract surgery does not reduce the rate of complications during the perioperative period. The results also suggest it would be more efficient not to request routine preoperative tests unless indicated by patient history or physical examination.

The value of routine preoperative medical testing before cataract surgery. Study of Medical Testing for Cataract Surgery.
Schein OD, Katz J, Bass EB, Tielsch JM, Lubomski LH, Feldman MA, Petty BG, Steinberg EP.
Dana Center for Preventive Ophthalmology, Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD, USA. oschein@jhmi.edu

N Engl J Med 2000 Jan 20;342(3):168-75

BACKGROUND: Routine preoperative medical testing is commonly performed in patients scheduled to undergo cataract surgery, although the value of such testing is uncertain. We performed a study to determine whether routine testing helps reduce the incidence of intraoperative and postoperative medical complications. METHODS: We randomly assigned 19,557 elective cataract operations in 18,189 patients at nine centers to be preceded or not preceded by a standard battery of medical tests (electrocardiography, complete blood count, and measurement of serum levels of electrolytes, urea nitrogen, creatinine, and glucose), in addition to a history taking and physical examination. Adverse medical events and interventions on the day of surgery and during the seven days after surgery were recorded. RESULTS: Medical outcomes were assessed in 9408 patients who underwent 9626 cataract operations that were not preceded by routine testing and in 9411 patients who underwent 9624 operations that were preceded by routine testing. The most frequent medical events in both groups were treatment for hypertension and arrhythmia (principally bradycardia). The overall rate of complications (intraoperative and postoperative events combined) was the same in the two groups (31.3 events per 1000 operations). There were also no significant differences between the no-testing group and the testing group in the rates of intraoperative events (19.2 and 19.7, respectively, per 1000 operations) and postoperative events (12.6 and 12.1 per 1000 operations). Analyses stratified according to age, sex, race, physical status (according to the American Society of Anesthesiologists classification), and medical history revealed no benefit of routine testing. CONCLUSIONS: Routine medical testing before cataract surgery does not measurably increase the safety of the surgery.

Do ophthalmologists, anesthesiologists, and internists agree about preoperative testing in healthy patients undergoing cataract surgery?
Bass EB, Steinberg EP, Luthra R, Schein OD, Tielsch JM, Javitt JC, Sharkey PD, Petty BG, Feldman MA, Steinwachs DM.
Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Arch Ophthalmol 1995 Oct;113(10):1248-56

To assess variation in reported use of preoperative medical tests in patients undergoing cataract surgery and to identify factors that influence test use by different physician groups we performed a national survey of ophthalmologists, anesthesiologists, and internists. Participants included randomly selected members of American professional societies who provided care to one or more patients undergoing cataract surgery in 1991. Responses were obtained from 538 (82%) of 655 eligible ophthalmologists, 109 (76%) of 143 anesthesiologists, and 54 (44%) of 122 internists. Fifty percent of ophthalmologists, 40% of internists, and 33% of anesthesiologists frequently or always obtained a chest x-ray film, while 20% of ophthalmologists, 27% of internists, and 37% of anesthesiologists never obtained a chest x-ray film for patients being considered for cataract surgery who had no history of major medical problems (P < .01 for differences between ophthalmologists and the other groups). Similarly, 70% to 90% of ophthalmologists, 73% to 79% of internists, and 41% to 79% of anesthesiologists frequently or always obtained a complete blood cell count, electrolyte panel, and electrocardiogram, while 4% to 11% of ophthalmologists, 13% to 17% of internists, and 9% to 28% of anesthesiologists never obtained these tests for such patients. Many respondents (32% to 80%) believed tests were unnecessary but cited multiple reasons for obtaining tests (eg, medicolegal concerns and institutional requirements). Many physicians in each group viewed preoperative evaluations as screening opportunities or believed that one of the other two types of physicians "required" tests. We conclude that marked variation exists within and across physician specialties in the use and rationale for use of medical tests in patients undergoing cataract surgery.

Usefulness of selectively ordered preoperative tests.
Charpak Y, Blery C, Chastang C, Ben Kemmoun R, Pham J, Brage D, Zindel G, Tref D, Taviot F.
Departement de biostatistique et informatique medicale, Hopital Saint-Louis, Paris, France.
Med Care 1988 Feb;26(2):95-104

The authors prospectively evaluated the usefulness of 12 preoperative tests (including blood type and screen) ordered selectively according to clinical status and importance of scheduled surgery. Two methods of assessing usefulness of tests were used, taking into account not simply their abnormality yield, but also their impact on patient care during the entire hospitalization: first, usefulness was assessed by anesthetists involved in care; second, usefulness was assessed by an automated analysis of specific clinical situations in which tests were a priori considered useful. In 3,866 patients 15,920 tests were performed; 30% of performed tests were abnormal. As a consequence of test results, surgery was delayed or cancelled in 19 patients and modified in 1, and a treatment was instituted or anesthetic management influenced in 347 (9%). Blood component therapy was instituted in 652 patients (17%). Anesthetists and automated analysis found at least one preoperative test useful in 931 patients (24%) and 890 patients (23%), respectively, whereas on a per-test basis 17% and 9% of tests were found useful. The discrepancy in usefulness assessment was mainly due to differences in evaluation of the usefulness of normal results. This study shows that the usefulness of selectively ordered preoperative tests may be high, but better criteria for their indications are needed, because tests other than those recommended by protocol were found useful.

[Which preoperative tests in ambulatory surgery?]
[Article in French]
Landais A.
Service d'Anesthesie-Reanimation, Centre hospitalier Victor-Dupouy, Argenteuil.
Cah Anesthesiol 1993;41(5):511-9

Anaesthesia for ambulatory surgery implies a strict selection of patients. Screening tests are non specific, compared to these ordered for in-patients. However, detailed preoperative evaluation is mandatory for ambulatory care to function correctly. Many studies conclude that 60% of routine screening tests are of no value: no proven benefit in either anaesthetic management or in the detection of pathologies which might interfere with anaesthesia has been shown with systematic preoperative examinations in asymptomatic subjects (adults or children). The detection of an asymptomatic anomaly by routine testing is extremely infrequent and does not lead to changes in the operating schedule or in the outcome of anaesthesia. Clinical examination and patient history are the only predictive elements, so systematic complementary tests should be abandoned and replaced by judicious selective prescription.

Preoperative laboratory testing for the oral and maxillofacial surgery patient.
Wagner JD, Moore DL.
Truman Medical Center and Affiliated Hospitals, University of Missouri-Kansas City School of Medicine and Dentistry.
J Oral Maxillofac Surg 1991 Feb;49(2):177-82

Studies estimate that approximately 60% of preoperative testing could be eliminated without adversely affecting patient care. Unnecessary testing tends to cause extra risk to the patient, inefficient operating room schedules, and unnecessary costs. These extra tests may be hazardous to patients because of the pursuit and treatment of borderline positive or false-positive results. Furthermore, extra testing may also increase medicolegal risk, because the abnormalities that are discovered are usually not noted on the chart. A reliable and effective method for ordering laboratory tests to assess patients preoperatively and reduce morbidity and cost is presented.

Unindicated preoperative testing: ASA physical status and financial implications.
Vogt AW, Henson LC.
Department of Anesthesiology, University of Rochester School of Medicine, NY 14642, USA.

J Clin Anesth 1997 Sep;9(6):437-41

STUDY OBJECTIVE: To determine if the ordering of unindicated preoperative laboratory tests is different for healthy (ASA physical status I and II) versus sicker (ASA physical status III) patients, and to examine the financial implications at our institution of unindicated preoperative testing. DESIGN: Prospective, cross-sectional study. SETTING: University hospital. PATIENTS: 383 consecutive patients scheduled for elective surgery and seen by an anesthesiologist in the Preoperative Clinic. Complete data was available for 312 patients. MEASUREMENTS AND MAIN RESULTS: Preoperative laboratory tests ordered by the surgeon were compared to those tests considered indicated by one of several anesthesiologists for ASA physical status I and II versus ASA physical status III patients. An average of 72.5% of tests ordered by surgeons were considered not indicated by the anesthesiologists. ASA physical status III patients had significantly fewer unindicated complete blood count, platelet count, prothrombin time, partial thromboplastin time, chemistry 12 profile, and chest radiography orders than did ASA physical status I and II patients. Our hospital could generate approximately $80,000 in variable and semifixed cost savings by eliminating these unindicated preoperative tests for the 5,100 patients seen in Preoperative Clinic annually (29% of the total surgical patients). CONCLUSIONS: A large percentage of preoperative tests ordered by surgeons at our institution are not indicated. Eliminating unindicated tests would cut hospital revenues in a climate where testing is fee-for-service and would save the hospital money in a managed-care or capitated system.

How much routine preoperative laboratory testing is enough?
Velanovich V.
Ireland Army Community Hospital, Fort Knox, KY 40121-5520.

Am J Med Qual 1993 Fall;8(3):145-51

Routine preoperative laboratory testing has become dogma to many. Often, surgeons, anesthesiologists, hospital administrators, and even patients expect that there will be some "labs" on the chart prior to any operative procedure. Many have questioned the usefulness and cost-effectiveness of such a policy. There is little evidence to support the need for routine preoperative testing and much evidence against it. Preoperative testing should be based on appropriate indications. This makes the assessment of the preoperative laboratory evaluation difficult for a medical quality assurance program. The question that arises is, how much routine preoperative laboratory testing is enough? The answer to this question depends on (a) the purpose of this testing and (b) the limitations and potential misinterpretations of laboratory testing. This article will discuss the reasons for the potential misinterpretation of laboratory tests and then the data supporting selective preoperative laboratory testing.

The value of routine preoperative laboratory testing in predicting postoperative complications: a multivariate analysis.
Velanovich V.
Department of Surgery, Letterman Army Medical Center, Presidio of San Francisco, Calif.

Surgery 1991 Mar;109(3 Pt 1):236-43

The purpose of this study was to evaluate the ability of preoperative laboratory testing to predict postoperative complications. Five hundred twenty patients undergoing elective surgery had their American Society of Anesthesiologists' classification, ponderal index, electrolyte values, glucose levels, blood urea nitrogen/creatinine values, complete blood counts, coagulation studies, total protein/albumin/lymphocyte count, electrocardiogram, chest radiograph, urinalysis, pulmonary function tests, type of anesthesia, and type of operation recorded preoperatively. Patients were followed prospectively after surgery for the development of complications. The data were analyzed by univariate and multivariate methods. Postoperative complications were strongly associated with American Society of Anesthesiologists' classification, type of anesthesia, and type of operation. However, only a few laboratory tests, such as electrocardiogram, chest radiograph, and nutritional status, were associated with postoperative complications. Therefore, in general, preoperative laboratory testing should only be undertaken for specific indications. Recommendations for routine tests are made depending on the age of the patient.

The utility of preoperative laboratory testing in general surgery patients for outpatient procedures.
Wattsman TA, Davies RS.
Department of Surgery, Carilion Roanoke Memorial Hospital, Virginia 24033, USA.
Am Surg 1997 Jan;63(1):81-90

The utility of obtaining routine preoperative laboratory (lab) screening tests was evaluated for a 1-year period in general surgery clinic patients undergoing ambulatory surgical procedures at a teaching hospital. This study sought to determine whether those lab tests not indicated by patient history or physical examination would identify abnormalities that might influence perioperative care of the ambulatory surgical patient or predict perioperative complications. The charts of 142 patients undergoing 155 procedures were reviewed. A total of 300 tests were ordered, with 92 (30.6%) being abnormal. Of the 125 tests indicated, 54 (43.2%) were abnormal, whereas in those lab tests not indicated, 38 (21.7%) were found to be abnormal. In four instances, an abnormal lab test (4 out of 300) result was clinically significant (1.3%), causing cancellation of the surgical procedure in two cases (both indicated lab tests) and diagnosis of urinary tract infection in two patients (both routine urinalyses). Forty-eight of the 142 patients had no preoperative lab tests ordered (34%), with no perioperative complications resulting. Patient charges totaled $15,725 for all lab tests ordered, with $8,573 in charges attributed to those tests not indicated. If lab tests for all general and subspecialty surgical outpatients had been ordered as dictated by patient medical history and physical examination rather than by either routine or by arbitrary criteria, our medical facility could have potentially reduced patient charges by more than $400,000 in the year reviewed, assuming a 52.4 per cent savings as noted above, with no expected adverse outcomes.

Ambulatory anesthesia: which preoperative screening tests are required]
[Article in German]
Hesse S, Seebauer A, Schwender D.
Institut fur Anaesthesiologie, Ludwig-Maximilians-Universitat, Klinikum Grosshadern, Munchen.

Anaesthesist 1999 Feb;48(2):108-15

The volume of preoperative screening investigations for outpatient anaesthesia ranges from few, selectively ordered investigations to extensive routine diagnostic procedures. It seem appropriate to reevaluate benefit and efficacy of routine preoperative assessment programs. The purpose of preoperative diagnostic is to assess the risk of anaesthesia and surgery for the patient. As shown by a number of studies, preoperative screening investigations seldom disclose new pathological findings of clinical relevance. Abnormal laboratory results in otherwise healthy patients rarely alter the anaesthetic management of the patient and are not related to perioperative complications. Extensive use of costly diagnostic procedures considerably increases health care budgets. A more selective approach to order preoperative investigations promises considerable savings. To achieve costeffective evaluation an efficient organisation of properative assessment must be established to avoid costly delay and on day-of-surgery-cancellations. There is no medicolegal obligation to perform routine diagnostic testing. The anaesthetist must be sufficiently informed in time to assess the perioperative risk of the patient and to alter anaesthetic management as necessary. According to the presented studies a clinical history and a through physical examination represent an effective method of screening for the presence of disease. Careful medical history evaluation and physical examination can avoid extensive investigations in apparently healthy individuals and the latter should only be ordered if indicated.

Cost-effectiveness of preoperative examinations.
France FH, Lefebvre C.
Departement de Medecine Interne, Service de Medecine Interne Generale, Cliniques Universitaires St-Luc, Bruxelles.

Acta Clin Belg 1997;52(5):275-86

Preoperative medical evaluation is needed to assess individual patients risks of perioperative morbidity and mortality. The content of the preoperative examination remains the object of discussion. Although a well documented preoperative assessment of a patient's health status might allow to optimise his condition before surgery and to plan the most appropriate perioperative management, leading to an improvement of perioperative outcome as well as a reduction in costs, data to support this claim are still most often indirect. A large number of patients remain asymptomatic, with normal tests, which raises questions about the appropriateness to request a battery of tests on every candidate to surgery. Patients risks should be assessed mainly by history and physical examination, which might reduce drastically preoperative indication of laboratory tests: age, operation site, preoperative diseases and emergent surgery are important factors to consider. A risk estimate is presented, as well as recommendations for a preoperative health assessment, by categories of patients, following a screening pathway. Costs have been estimated in various alternatives. They have been evaluated to be above 2 billion BEF per year in Belgium for 563,485 surgical cases, and could most likely be reduced by about 60% in a near future.

Preoperative work up: are the requirements different in a developing country?
Pal KM, Khan IA, Safdar B.
Department of Surgery, Aga Khan University Hospital, Karachi.

J Pak Med Assoc 1998 Nov;48(11):339-41

In developing countries there is a tendency to advocate routine testing in asymptomatic healthy patients to identify undocumented significant medical conditions. A retrospective review of pre- operative laboratory investigations undertaken in patients attending the General Surgical department was performed. Three hundred and twenty patients case notes were reviewed, patients were selected on the basis of common general surgical procedures. Two hundred and sixteen patients (67.5%) did not have any associated medical illness on history and physical examination. Analysis of laboratory results showed that 42/216 (19.4%) had low hemoglobin. An abnormal chest X-ray was the next common abnormality 11/103 (10.6%). Mild hypokalemia (> 3 mEq/L) was seen in 6/123 (4.8%) and a raised blood sugar level was seen in 1/113 (0.88%) patients. Only one patient with hemoglobin of 4.8 gm/dL needed preoperative intervention, the rest of the abnormalities did not effect the treatment plan or outcome. The results were in general agreement with other studies except for the high proportion of low hemoglobin seen in the female population. It is suggested that a thorough history and physical examination is a reliable and inexpensive preoperative screening tool. Guidelines for pre-operative investigations in American Society of Anesthesiologists Grade I (ASA I) patients are suggested.

"Routine" preoperative studies. Which studies in which patients?
Marcello PW, Roberts PL.
Department of Colon and Rectal Surgery, Lahey-Hitchcock Clinic, Burlington, MA, USA.
Surg Clin North Am 1996 Feb;76(1):11-23

The utility of mass screening of preoperative patients has never been demonstrated for the majority of tests. Although screening patients to uncover occult disease appears logical, in reality it has resulted in excessive expenditure of our health care dollars with limited benefit. More than $30 billion is spent annually on preoperative examinations, 60% of which are unnecessary. In addition, iatrogenic injury has resulted from the further evaluation and treatment of false-positive results. A selective utilization of routine examinations can accurately supplement the clinician's evaluation, providing the patient with a complete preoperative assessment. The benefits of selective testing must be balanced against the possible omission of warranted examinations, highlighting the need for a more reliable system for test ordering.

[Preoperative testing routines for healthy, asymptomatic patients in the Canary Islands (Spain)]
[Article in Spanish]
Serrano Aguilar P, Lopez Bastida J, Duque Gonzalez B, Pino Capote J, Gonzalez Miranda F, Rodriguez Perez A, Erdocia Eguia J.
Servicio del Plan de Salud, Investigacion y Evaluacion de Tecnologias Sanitarias. Servicio Canario de Salud.

Rev Esp Anestesiol Reanim 2001 Aug-Sep;48(7):307-13

Objectives: To analyze patterns of routine testing before elective/scheduled surgery in healthy/asymptomatic patients classified as ASA I or II according to the American Society of Anesthesiologists.Material and method: A questionnaire on the organization of preoperative testing was completed by anesthesiologists at five public hospitals in the Canary Islands. The questionnaire emphasized the most commonly ordered screening procedures, such as chest X-rays, electrocardiograms, laboratory tests and spirometry.Results: Red cell counts were most frequently requested (for 86% of the patients), followed by platelet counts (80%) and blood chemistry (75%) and coagulation studies (72%). Least requested were urine tests and spirometry. The frequencies of electrocardiogram and chest X-ray requests fell between the two extremes, with patient age and the presence of certain indications seeming to affect whether those tests would be ordered or not. The need for such screening was perceived to increase for patients over 40 years of age. The ordering of preoperative tests varied from hospital to hospital and among anesthesiologists at a single site in spite of established protocols. Conclusions: Hospitals and individual anesthesiologists differ considerably in how they request preoperative tests. The variations can not be explained solely by differing patient needs given that respondents were contemplating only healthy/asymptomatic individuals undergoing relatively simple procedures.

[Survey on the preoperative evaluation in Catalonian surgical centers. I. What is the preoperative routine?]
[Article in Spanish]
Vilarasau Farre J, Martin-Baranera M, Oliva G.
Consorci Sanitari de la Creu Roja a Catalunya, L'Hospitalet de Llobregat, Barcelona. Jordi.Vilarasau@chcr.scs.es

Rev Esp Anestesiol Reanim 2001 Jan;48(1):4-10

OBJECTIVE: To describe the preoperative assessment procedures currently used in hospitals in Catalonia (Spain). SUBJECTS AND METHODS: The study population consisted of all heads of departments of anesthesiology, general and gastrointestinal surgery, orthopedic surgery and traumatology of hospitals and clinics in Catalonia with active operating theaters. Information was obtained by self-administered questionnaire prepared by an interdisciplinary team. RESULTS: Of the 227 questionnaires sent, 139 (61%) were answered and returned. A preoperative assessment visit was programmed according to 112 (81%) of the respondents and 123 (89.8%) reported following a protocol that included ordering preoperative tests. The same tests were ordered for all patients by 25% of the respondents. A chest film and an ECG were always ordered according to 61 and 65%, respectively, and always when the patient was over a certain age according to 36 and 32%, respectively. Coagulation and blood sugar tests and a complete blood workup were always ordered according to 94%, 95% and 89%, respectively. Tests were considered valid for less than six months by most. CONCLUSIONS: This survey provides evidence of widespread use of preoperative assessment, although application falls short of including all scheduled patients. According to these results, selective protocols for ordering complementary preoperative tests are rarely applied.

[Survey on the preoperative evaluation in Catalonian surgical centers. II. What is the attitude and opinion of the professionals involved?]
[Article in Spanish]
Oliva G, Vilarasau Farre J, Martin-Baranera M.
Agencia d'Avaluacio de Tecnologia i Recerca Mediques, Barcelona. goliva@olimpia.scs.es

Rev Esp Anestesiol Reanim 2001 Jan;48(1):11-6

OBJECTIVE: Previous studies have provided evidence of the existence of differences in preoperative assessment practices and have questioned the usefulness of generalized testing for all patients. The objective of this study was to determine the attitudes and opinions of anesthesiologists and surgeons about their application of preoperative assessment procedures and their knowledge of the scientific principles underlying their practice. SUBJECTS AND METHODS: A questionnaire was mailed to 227 specialists in anesthesiology and postoperative intensive care, general and gastrointestinal surgery, orthopedic surgery and traumatology of all hospitals in Catalonia (Spain) with active operating theaters. RESULTS: The overall response rate was 61% of the surveyed population, with 86% of the Catalan hospitals represented. The medical literature supports the routine performance of a chest x-ray and an ECG in the opinion of 17 and 26% of the respondents, respectively. Those two procedures are always ordered by 43 and 37%, respectively, even if they believe that the medical literature does not support generalized application. Legal protection was given as the reason for routine ordering of preoperative tests in asymptomatic patients, and 89% believed that a protocol for selective preoperative assessment procedures would improve efficiency. CONCLUSIONS: This study reveals a discrepancy between the opinions of professionals involved in preoperative assessment and their real practice in Catalan hospitals, probably influenced by perceived need for legal protection.

Routine preoperative investigation. Results of a multicenter survey in Italy. Collaborator Group.
Ricciardi G, Angelillo IF, Del Prete U, D'Errico MM, Grasso GM, Gregorio P, Schioppa FS, Triassi M, Boccia A.
University of Cassino.
Int J Technol Assess Health Care 1998 Summer;14(3):526-34

We conducted a study to acquire information on the current behavior of a sample of Italian surgeons and anesthesiologists about prescribing, interpreting, and using routine preoperative investigations. Consultants in surgery and anesthesiology in 60 hospitals in northern, central, and southern Italy were interviewed. Prescription of these procedures by doctors were driven more by personal experience than by updated scientific knowledge. This practice often led to ineffective and inefficient clinical practice, with healthy patients undergoing useless, time-consuming, costly, and sometimes harmful procedures.

Medicolegal

What benefit and harm can be expected from screening and routine examinations and from their omission?]
[Article in German]
Kuss E, Tryba M, Kurzl R, Ulsenheimer K.
I. Frauenklinik der Universitat Munchen, Intensiv- und Schmerztherapie, Bochum.

Geburtshilfe Frauenheilkd 1991 Jun;51(6):415-30

Benefit and harm of screening and routine tests or their omission are dealt with in four parts. In the first part methods are described to evaluate the diagnostic value of medical testing. The concepts of diagnostic sensitivity, diagnostic specificity, and pre- and posttest probability of a diagnosis are defined. It is then shown how these concepts intercorrelate and how their numerical values can be calculated ("Bayes" theorem"). In consideration of the above mentioned intercorrelations, the second and third parts deal with the diagnostic value of preoperative routine tests from an anaesthesiological viewpoint, and the diagnostic value of other screening and follow-up tests is discussed from a gynaecological point of view. Pre-operative laboratory tests are necessary, and necessary only then, if careful evaluation of patient history and physical examination reveal pathological findings or risk factors. The benefits from regular lab-screening tests and follow-up tests, as recommended to the gynaecologists, are low. This is due to the large share of "healthy" women among the gynaecological patients, as well as the fact that treatment of early detected recurrences shows no demonstrable advantage over treatment of later detected recurrences. In the fourth part, we show that no adverse forensic consequences are to be expected if diagnostic tests are omitted because of demonstrably low diagnostic value. In case of legal procedures against the physician, a medical expert will have to evaluate the diagnostic value of the omitted test objectively from an "ex-ante" point of view, using the methods defined in the first part.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of the efficacy of routine preoperative electrocardiograms.
Tait AR, Parr HG, Tremper KK.
Department of Anesthesiology, University of Michigan Medical Center, Ann Arbor 48109, USA.

J Cardiothorac Vasc Anesth 1997 Oct;11(6):752-5

OBJECTIVE: To evaluate the efficacy of routine preoperative electrocardiograms (ECG) in predicting perioperative cardiovascular complications in an essentially healthy population. DESIGN: Retrospective chart review. SETTING: The adult hospital of a large academic medical center. PARTICIPANTS: One thousand ASA class I and II adult patients undergoing a number of different elective surgical procedures. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The mean age of the population was 48 years (range, 18 to 88), and 53% were female. Fifty-seven percent of the population had a preoperative ECG, of which 56.5% were considered normal, 37.8% were abnormal, and 6.6% were considered borderline. Twenty-seven percent of the population presented with cardiovascular risk factors, and of these, 93.2% had an ECG performed. Seventy-three percent of patients had no cardiovascular risk factors, and of these, 44.5% had a preoperative ECG. Patients who had cardiovascular risk factors had significantly more abnormal ECGs than those without (51% v 26.1%,); however, there was no difference in the prevalence of perioperative events between the two groups. The positive predictive value of an abnormal ECG for a perioperative event was slightly greater for patients with cardiovascular risk factors than for those without (42.7% v 34.7%, respectively); however, this difference was not significant. In addition, a normal ECG was just as predictive as an abnormal one. CONCLUSIONS: Results of this study suggest that the practice of routine ECG screening for patients with no cardiovascular risk factors is a poor predictor of perioperative complications in this patient population. A review of the current criteria for ordering preoperative ECGs may reduce the number of unnecessary tests and improve cost-effectiveness.

Changes

Impact of new guidelines on physicians' ordering of preoperative tests.
Mancuso CA.
Cornell University Medical College, Cornell University Graduate School of Medical Sciences, and Hospital for Special Surgery, New York, NY 10021, USA.

J Gen Intern Med 1999 Mar;14(3):166-72

OBJECTIVE: To compare the number of preoperative tests ordered for elective ambulatory surgery patients during the 2 years before and the 2 years after the establishment of new hospital testing guidelines. MEASUREMENTS: The patterns of preoperative testing by surgeons and a medical consultant during the 2 years before and the 2 years after the establishment of new guidelines at one orthopedic hospital were reviewed. All tests ordered preoperatively were determined by review of medical records. Preoperative medical histories, physical examinations, and comorbidities were obtained according to a protocol by the medical consultant (author). Perioperative complications were determined by review of intraoperative and postoperative events, which also were recorded according to a protocol. MAIN RESULTS: A total of 640 patients were enrolled, 361 before and 279 after the new guidelines. The mean number of tests decreased from 8.0 before to 5.6 after the new guidelines ( p =.0001) and the percentage decrease for individual tests varied from 23% to 44%. Except for patients with more comorbidity and patients receiving general anesthesia, there were decreases across all patient groups. In multivariate analyses only time of surgery (before or after new guidelines), age, and type of surgery remained statistically significant ( p =.0001 for all comparisons). Despite decreases in surgeons' ordering of tests, the medical consultant did not order more tests after the new guidelines ( p =.60) The majority of patients had no untoward events intraoperatively and postoperatively throughout the study period, with only 6% overall requiring admission to the hospital after surgery, mainly for reasons not related to abnormal tests. Savings from charges totaled $34,000 for the patients in the study. CONCLUSIONS: Although there was variable compliance among physicians, new hospital guidelines were effective in reducing preoperative testing and did not result in increases in untoward perioperative events or in test ordering by the medical consultant.

Cost-effective preoperative evaluation and testing.
Fischer SP.
Department of Anesthesia, Stanford University School of Medicine, Stanford University Hospital, CA 94305, USA. fischer_s@hosp.stanford.edu

Chest 1999 May;115(5 Suppl):96S-100S

Cost-effective preoperative evaluation can be approached from a variety of methods, educational strategies, and use of data to modify clinical practice. This article focuses on the proposed organizational and clinical changes in the process of preoperative evaluations, the cost-effective outcomes, and the relative merits these changes provide the physicians, operating room nurses, and center administrators.

OROMAXILLOFACIAL SURGERY

A prospective evaluation of the value of preoperative laboratory testing for office anesthesia and sedation.
Haug RH, Reifeis RL.
Division of Oral and Maxillofacial Surgery, MetroHealth Medical Center, Case Western Reserve University School of Medicine, Cleveland, OH 44109, USA.

J Oral Maxillofac Surg 1999 Jan;57(1):16-20; discussion 21-2

PURPOSE: The purpose of this investigation was to determine whether routine laboratory testing affected the clinician's preoperative evaluation and decision-making process for patients undergoing general anesthesia or intravenous sedation in the oral and maxillofacial surgery office. PATIENTS AND METHODS: This was a prospective evaluation of the records of 458 who required an office general anesthetic or intravenous sedation for routine dentoalveolar surgery. The patients ranged in age from 15 to 54 years and were categorized as American Society of Anesthesiologists Classification I or II. Fifty-two percent were female. All patients underwent a history and physical examination, complete blood cell count, and urine analysis. Female patients were tested for pregnancy by measuring the serum beta human chorionic gonadotropin level. All patients older than 40 years of age were further evaluated by posterior-anterior and lateral chest radiographs, as well as electrocardiography. On the day of surgery, the data were reviewed and analyzed, and specific components of the history were reassessed. The results of the decision-making process were evaluated by one investigator. RESULTS: From the 458 patients initially enrolled, 78 failed to return on the appointed day. Of the 235 patients requiring general anesthesia who did return on the appointed day, five had aberrant laboratory values (2%). These consisted of one patient with a low hematocrit, one with a low red blood cell count, one with a low white blood cell count, and two with a urine analysis positive for blood. No procedure was canceled based on the aberrant data. Of the 145 patients requiring intravenous sedation who did return on the appointed day, six had aberrant laboratory values (4%). Two patients exhibited elevated white blood cell counts, two possessed low red blood cell counts, one known to have diabetes had an elevated urine glucose, and one patient with an elevated human chorionic gonadotropin level realized that her menstrual cycle was delayed. The latter two patients had their procedures deferred. CONCLUSIONS: Based on the results of this study, a good history and physical examination and then reassessment of key portions of the history were the major factors in the development of the anesthetic treatment plan. Laboratory data had little if any effect on the decision-making process.

GERIATRIC

Relative importance of preoperative health status versus intraoperative factors in predicting postoperative adverse outcomes in geriatric surgical patients.
Leung JM, Dzankic S.
Department of Anesthesia and Perioperative Care, University of California, San Francisco, California 94143, USA.

J Am Geriatr Soc 2001 Aug;49(8):1080-5

OBJECTIVES: To determine the prevalence and predictors of adverse postoperative outcomes in older surgical patients undergoing noncardiac surgery. DESIGN: Prospective cohort study of consecutive patients undergoing noncardiac surgery in 1997. SETTING: A medical school-affiliated teaching community hospital. PARTICIPANTS: Patients age 70 and older undergoing noncardiac surgery. Patients presenting for surgery requiring only local anesthesia or monitored anesthesia care were excluded. MEASUREMENTS: Potential pre- and intra-operative risk factors were measured and evaluated for their association with the occurrence of predefined in-hospital postoperative adverse outcomes. Univariate predictors of postoperative outcomes were first measured using the chi-square or Fisher's exact tests followed by multivariate logistic regression. Odds ratios (OR) with 95% confidence interval (CI), and two-sided P-values were reported. RESULTS: Five hundred forty-four consecutive patients were studied. Overall, 21% of patients developed one or more postoperative adverse outcomes and 3.7% died during the in-hospital postoperative period. Of all the adverse outcomes, cardiovascular complications (10.3%) were the leading cause of morbidity, followed by neurological (7.7%) and pulmonary complications (5.5%). By multivariate logistic regression analysis, American Society of Anesthesiologists (ASA) classification (OR = 2.7, CI = 1.6-4.4), emergency surgery (OR = 2.0, CI = 1.1-3.4), and intraoperative tachycardia (OR = 3.8, CI = 1.9-7.6) were the most important predictors of postoperative adverse outcomes. Of all the preoperative physical symptoms and signs, decreased functional status (OR = 3.0, CI = 1.4-6.4) and clinical signs of congestive heart failure (OR = 2.1, CI = 1.1-5.1) were the two most important predictors of postoperative adverse neurological and cardiac outcomes, respectively. The median hospital stay was 4 days. The patients who developed postoperative adverse outcomes had significantly longer median hospital stays (9 days) than those without complications (3 days), (P < .0001). CONCLUSION: Our study demonstrates that the postoperative mortality rate in geriatric surgical patients undergoing noncardiac surgery is low. Despite the prevalence of preoperative chronic medical conditions, most patients do well postoperatively. The ASA classification (a reflection of the severity of preoperative comorbidities), emergency surgery, and intraoperative tachycardia increase the odds of developing any postoperative adverse events. Future studies aimed at modifying some of the potentially reversible risk factors, such as preoperative heart function and intraoperative heart rate are warranted.

The prevalence and predictive value of abnormal preoperative laboratory tests in elderly surgical patients.
Dzankic S, Pastor D, Gonzalez C, Leung JM.
Department of Anesthesia and Perioperative Care, Mount Zion Medical Center, University of California-San Francisco, 1600 Devisadero Street, San Francisco, CA 94143-1605.

Anesth Analg 2001 Aug;93(2):301-8 , 2nd contents page

Because data to determine which preoperative laboratory tests are important in elderly surgical patients are limited, we performed a prospective cohort study to evaluate the prevalence and predictive value of abnormal preoperative laboratory tests in consecutive patients > or =70 yr old who were undergoing noncardiac surgery. Patients presenting for surgery requiring only local anesthesia or monitored anesthesia care were excluded. Preoperative risk factors and laboratory test results were measured and evaluated for their association with the occurrence of predefined in-hospital postoperative adverse outcomes. In 544 patients, the prevalence of preoperative electrolytes and platelet count abnormalities (<115 x10(9)/L) was small (0.5%-5%), and abnormal creatinine (>1.5 mg/dL), hemoglobin (<10 g/dL), and glucose (>200 mg/dL) values were 12%, 10%, and 7%, respectively. Univariate predictors for adverse outcome of abnormal sodium and creatinine were not as predictive as ASA classification and surgical risk. By multivariate logistic regression, only ASA classification (>II) (odds ratio [OR], 2.55; 95% confidence interval [CI], 1.56-4.19; P < 0.001) and surgical risk (OR, 3.48; 95% CI, 2.31-5.23; P < 0.001) were significant independent predictors of postoperative adverse outcomes. The prevalence of abnormal preoperative electrolyte values and thrombocytopenia was small and had low predictive values. Although more prevalent, abnormal hemoglobin, creatinine, and glucose values were also not predictive of postoperative adverse outcomes. Routine preoperative testing for hemoglobin, creatinine, glucose, and electrolytes on the basis of age alone may not be indicated in geriatric patients. Rather, selective laboratory testing, as indicated by history and physical examination, which will determine patient's comorbidities and surgical risk, seems to be indicated. IMPLICATIONS: The prevalence of abnormal preoperative electrolyte values and thrombocytopenia was small and had low predictive values. Although more prevalent, abnormal hemoglobin, creatinine, and glucose values were also not predictive of postoperative adverse outcomes. Routine preoperative testing for hemoglobin, creatinine, glucose, and electrolytes on the basis of age alone may not be indicated in geriatric patients. Rather, selective laboratory testing, as indicated by history and physical examination, which will determine patient's comorbidities and surgical risk, seems to be indicated.

PEDIA

Is preoperative haemoglobin testing justified in children undergoing minor elective surgery?
Roy WL, Lerman J, McIntyre BG.
Department of Anaesthesia, Hospital for Sick Children, University of Toronto, Ontario.
Can J Anaesth 1991 Sep;38(6):700-3

The need for preoperative haemoglobin determination before the administration of general anaesthesia to paediatric patients has long been an issue for debate. This study was undertaken to determine the value of routine preoperative haemoglobin testing in paediatric patients scheduled for minor surgery. Two thousand patients ages one month to 18 yr scheduled for minor surgery were studied. The patients were grouped according to age, Group I less than or equal to yr, Group II 1-5 yr, Group III greater than 5 yr. The charts of patients whose preoperative haemoglobin concentration (Hb) was less than 100 g.L-1 were reviewed at a later date to determine the course of their anaesthesia and surgery. Eleven patients, all of whom were greater than 5 yr (0.5%), had a Hb less than 100 g.L-1. Of these, three patients, 27%, had their surgery deferred, whereas the remaining eight patients, 73%, underwent anaesthesia and surgery without complications. The three patients who were deferred returned for uneventful anaesthesia and surgery following oral iron therapy. We conclude that healthy paediatric patients five years and older scheduled for minor surgery do not require routine Hb determinations. Furthermore, the low incidence of anaemia and low deferral rate of anaemic children, 1-5 yr of age, lead us to question the value of preoperative Hb testing in this age group.

[Limited value of routine preoperative laboratory studies in children]
[Article in Dutch]
de Vries TW, Harbers JS, Heymans HS, Harbers HS.
Academisch Ziekenhuis, Afd, Kindergeneeskunde, Groningen.

Ned Tijdschr Geneeskd 1992 Sep 12;136(37):1810-3

In order to determine whether in routine preoperative laboratory testing of children abnormal results were reported which influenced the course of the anesthesia or of the operation, a retrospective survey of charts was carried out at the University Children's Hospital, Groningen. The patients involved were 143 low risk children, admitted for ENT surgery. The main outcome measures were abnormalities and perioperative complications. There were 1.4% laboratory abnormalities (including five children with a haemoglobin concentration less than 7.1 mmol/l, one with a calcium concentration less than 2.2 mmol/l, one with an albumin concentration less than 30 g/l), and seven complications (bradycardia during intubation, bronchial obstruction, bleeding, excessive vomiting (three times), and leakage of perilymphatic fluid). There were no correlations between the abnormal test results and the complications. Routine laboratory testing in children scheduled for surgery might be reduced to measurement of haemoglobin, especially in non-white children.

The usefulness of routine preoperative laboratory tests for one-day surgery in healthy children.
Meneghini L, Zadra N, Zanette G, Baiocchi M, Giusti F.
Anesthesiology and Intensive Care Institute, University of Padua, Italy.

Paediatr Anaesth 1998;8(1):11-5

Since 1984, laboratory tests have not been routinely required for healthy paediatric patients scheduled for one-day surgery in our Paediatric Surgery Department. We reviewed the medical charts of all children ASA physical status 1 and 2 who underwent a minor surgical procedure in the last 15 years. We excluded all former preterm infants of less than 60 weeks postconceptual age. The series under examination includes two groups of patients: group A includes 1884 children who underwent routine preoperative laboratory tests; group B includes 8772 children who had preoperative, selected laboratory tests performed only when the child's history and/or clinical examination revealed some abnormalities. The following data were collected: demographic data, ASA physical status classification, surgical procedure, anaesthetic technique, major and minor complications, length of hospital stay, the difference between the expected length of hospitalization and the actual length, number and reasons for cancellations of surgery. On the basis of our experience we believe that a thorough clinical assessment of the patient is more important than routine preoperative laboratory screening, which should be required only when justified by real clinical indications. Moreover, this practice eliminates unnecessary costs without compromising the safety and the quality of care.

Preoperative laboratory testing in children undergoing elective surgery: analysis of current practice.
Patel RI, DeWitt L, Hannallah RS.
Department of Anesthesiology, Children's National Medical Center, Washington, D.C. 20010, USA.

J Clin Anesth 1997 Nov;9(7):569-75

STUDY OBJECTIVE: To evaluate current practice in preoperative testing of healthy children undergoing elective surgery that is not expected to result in significant blood loss. DESIGN: Survey of members of the Society for Pediatric Anesthesia. SETTING: Anesthesiologists practicing in North America. POPULATION: A total of 1,200 questionnaires were mailed. INTERVENTIONS: Questionnaires were mailed to all members of the Society for Pediatric Anesthesia. All members were asked to specify which tests were routinely performed and to state why. Specific questions were asked about performing complete blood count (CBC), hemoglobin (Hb), hematocrit (Hct), and urine analysis (UA) in all patients, pregnancy test in adolescents, prothrombin time (PT) and activated partial thrombin time (PTT) prior to tonsillectomy, and sickle cell testing in black and/or Mediterranean children. MEASUREMENTS AND MAIN RESULTS: 685 of 1,200 (57%) questionnaires were returned. No attempt was made to identify and follow-up with nonresponders. Hb testing is routinely performed in 27% to 48% of the children depending on the age of the patient. UA is ordered preoperatively in less than 15% of the children. Pregnancy test was ordered by 43% of the respondents. Hemostatic tests prior to tonsillectomy were conducted by 45% of the anesthesiologists. CONCLUSION: The results indicate the present practice of routine preoperative laboratory testing for children undergoing elective outpatient surgery. In spite of the many studies that indicate no specific benefits of performing routine preoperative testing in healthy children undergoing scheduled surgery, many physicians continue to order these tests in all such children.

Responsibility of the anaesthesiologist in the preoperative risk evaluation]
[Article in German]
Lingnau W, Strohmenger HU.
Klinik fur Anaesthesie und Allgemeine Intensivmedizin, Leopold-Franzens-Universitat Innsbruck.
Anaesthesist 2002 Sep;51(9):704-15

Correct indications are essential to perform surgical procedures. However, appropriate timing to achieve minimal rates of complications even in high-risk patients or major surgery is at the top of the priority list. Perioperative responsibility is divided between anaesthesiologists and surgeons. While the surgeon is accountable for the surgical procedure, the anaesthesiologist is responsible for preoperative risk evaluation, perioperative management, and maintenance of vital organ functions. Both of these medical specialities must weigh the urgency of the procedure against patient-associated risk factors. Goals are optimal patient safety, efficient preoperative evaluation and subsequent optimisation to reduce the burden for the health care systems. For most patients without underlying diseases, a thorough history and physical examination is sufficient. In teaching hospitals, some laboratory results for screening of organ function are advisable. Patients can be stratified on clinical grounds into low-, medium-, and high-risk categories. Use of these categories, along with consideration of the type and urgency of surgery, allows for a reasonable approach to preoperative testing. Testing directed towards assessment of organ system functional reserve and identification of organs at risk rather than the diagnosis of a specific disease, is the primary goal of preoperative evaluation prior to surgery. These results are essential to prepare an effective anaesthetic plan. Along with increased patient comfort, the number of preoperative hospital days can be reduced by outpatient preoperative evaluation clinics.

A prospective evaluation of preoperative screening laboratory tests in general surgery patients.
Alsumait BM, Alhumood SA, Ivanova T, Mores M, Edeia M.
Department of Surgery, Mubarak Al-Kabeer Hospital, PO Box 441, 45705 Alsurrah, Kuwait. balsumait@hotmail.com
Med Princ Pract 2002 Jan-Mar;11(1):42-5

OBJECTIVE: To assess the value of routine biochemical and hematological screening of otherwise healthy patients prior to elective general surgery. MATERIALS AND METHODS: Prospective laboratory screening tests were done for 1,000 consecutive patients undergoing elective general surgery at Mubarak Al-Kabeer Hospital, Kuwait, from January to August 1999. Patients with abnormal laboratory results were interviewed and examined preoperatively as part of the present study protocol, to identify a possible cause for the abnormal laboratory result. The perioperative course of these patients was also monitored. RESULTS: Approximately 14% of the preoperative tests were abnormal, 9.2% of which was expected while 4.9% was unexpected; there was no change in the preoperative care of patients with unexpected abnormalities, nor was there surgical delay or related postoperative complication. CONCLUSION: The results indicate that laboratory tests should be selectively used when the patient has appropriate risk factors. Instead, greater emphasis should be placed on history and physical examination. Application of such policy will result in substantial financial savings that could be utilized to improve the health care system.

The value of routine preoperative investigations.
McKee RF, Scott EM.

Ann R Coll Surg Engl 1987 Jul;69(4):160-2

In a prospective study of 400 patients admitted for elective surgery, the value of preoperative investigations in identifying the group at high risk of complications was assessed. In order to evaluate methods of reducing the number of investigations a preoperative questionnaire was used and patients were also grouped with regard to age and extent of surgery. Sixteen per cent of the results of the preoperative investigations showed some abnormality but only 0.013% caused a change in management. Abnormal results were significantly associated with complications (P less than 0.05). A positive (abnormal) questionnaire and increased age together defined a group more likely to have abnormal results (P less than 0.05) but age was a more specific indicator. The extent of surgery was not associated with abnormal results other than biochemistry results but was associated with complications (P less than 0.01) and with the need to repeat investigations postoperatively. It was concluded that a preoperative questionnaire might be useful in the assessment of day case patients, where a larger fraction would be expected to fall into the low risk group. A policy for routine preoperative investigation was drawn up. Full blood count should be performed in all patients over 40 years, ECG in all patients over 50 years and CXR and urea and electrolytes in patients over 60 years undergoing major surgery. Asymptomatic patients out with these categories do not require routine investigations.

Preoperative work up: are the requirements different in a developing country?
Pal KM, Khan IA, Safdar B.
Department of Surgery, Aga Khan University Hospital, Karachi.

[Value of selective prescription of preanesthetic laboratory tests]
[Article in French]
Mignonsin D, Degui S, Kane M, Bondurand A.
Departement d'Anesthesie-Reanimation, CHU de Cocody.
Cah Anesthesiol 1996;44(1):13-7

The aim of this study was to determine the comparative value of routine or selective ordering of preoperative tests. 400 ASA I, II, III patients were enrolled in the study. Two periods were considered: a retrospective period where the patients (n = 200) underwent routine preoperative tests and a prospective period where the patients (n = 200) had only preoperative tests according to the results of questioning and clinical examination. During the retrospective period 1.408 tests were effected with 44 abnormal results. During the prospective period, the abnormal results among 855 prescribed tests were: 0.8% in ASA I patients, 7.5% in ASA II and 5.9% in ASA III patients. The ASA I patients had an average of 3.47 +/- 1.28 tests each, ASA II patients 4.50 +/- 1.21 and ASA III 7.50 +/- 1.50. No complication inducing sequelae or death could be linked to lacking tests. The mean cost of tests was reduced by 50 percent.

The impact of routine preoperative complete blood count (CBC) in elective operations in Srinagarind Hospital.
Bhuripanyo K, Khumsuk K, Sornpanya N, Wangsai W, Patoombal N.
Department of Medicine, Faculty of Medicine, Khon Kaen University, Thailand.

J Med Assoc Thai 1995 Jan;78(1):42-7

Because anemia and infectious diseases are still common, routine preoperative complete blood count (CBC) is often performed in most teaching hospitals in Thailand. However, there is growing consensus that it is of little benefit. We studied prospectively all patients who were scheduled for elective operation in Srinagarind Hospital. Medical history and physical examination were obtained prospectively without knowing the CBC result. Out of 1,013 patients interviewed, 955 were suitable for study, 384/955 (40.2%) of the CBC were abnormal. Significant anemia (hematocrit less than 30%) was found in 42 (4.4%), leukocytosis in 113 (11.8%), inadequate platelet in 3 (0.3%). The CBC abnormalities led to a change in management in 38 (4.0%). The clinical predictors of CBC abnormalities included weight loss, history of fever, presence of anemia and tender abdomen. In those with normal history and physical examination, the prevalence of anemia and CBC which led to management change was less than 1.7 per cent, regardless of age.

Routine pre-operative blood testing: is it necessary?
Johnson RK, Mortimer AJ.
Departments of Surgery and Anaesthesia, Wythenshawe Hospital, South Manchester University Hospitals Trust, Southmoor Road, Wythenshawe, Manchester M23 9LT, UK. marie.oliver@smuht.nwest.nhs.uk
Anaesthesia 2002 Sep;57(9):914-7

In order to determine the value of routine pre-operative screening investigations, the medical notes of 100 patients undergoing elective surgical procedures under general anaesthesia were subject to prospective audit. Pre-operative screening investigations (full blood count, urea and electrolytes and random glucose) were analysed in terms of frequency of abnormalities and whether or not the peri-operative management was changed when the result was abnormal. The frequency of results being present in the note at the time of operation and the costing of the tests was also examined. A total of 773 tests was performed of which 70 (9.1%) were abnormal. Peri-operative management was altered as a result of only two abnormal results (0.2%). Eight complications arose, none of which could have been predicted by the pre-operative screening tests. In only 57% of cases were the results present in the medical notes at the time of surgery. It is conservatively estimated that a saving of pound 50 000 per year could be made in our hospital alone by selective ordering of tests.

CATARACT SURGERY

Usefulness of selectively ordered preoperative tests. Charpak Y, Blery C, Chastang C, Ben Kemmoun R, Pham J, Brage D, Zindel G, Tref D, Taviot F. Departement de biostatistique et informatique medicale, Hopital Saint-Louis, Paris, France. Med Care 1988 Feb;26(2):95-104

Medicolegal

Changes

GERIATRIC

PEDIA

Usefulness of selectively ordered preoperative tests.
Charpak Y, Blery C, Chastang C, Ben Kemmoun R, Pham J, Brage D, Zindel G, Tref D, Taviot F.
Departement de biostatistique et informatique medicale, Hopital Saint-Louis, Paris, France.
Med Care 1988 Feb;26(2):95-104