Most preoperative laboratory tests (typically a complete blood count, prothrombin time and partial thromboplastin time, basic metabolic panel and urinalysis) performed on elective surgical patients are normal. Findings influence management in under 3% of patients tested. In almost all cases, no adverse outcomes are observed when clinically stable patients undergo elective surgery, irrespective of whether an abnormal test is identified. Preoperative laboratory testing is appropriate in symptomatic patients and those with risks factors for which diagnostic testing can provide clarification of patient surgical risk.
Sources:
Capdenat Saint-Martin E, et al. Description of local adaptation of national guidelines and of active feedback for rationalising preoperative screening in patients at low risk from anaesthetics in a French university hospital. Qual Health Care. 1998 Mar;7(1):5-11. PMID: 10178152.
Katz RI, et al. Survey study of anesthesiologists’ and surgeons’ ordering of unnecessary preoperative laboratory tests. Anesth Analg. 2011 Jan;112(1):207-12. PMID: 21081771.
Keay L, et al. Routine preoperative medical testing for cataract surgery. Cochrane Database Syst Rev. 2012 Mar 14;(3):CD007293. PMID: 22419323.
Munro J, et al. Routine preoperative testing: a systematic review of the evidence. Health Technol Assess. 1997;1(12):i-iv; 1-62. PMID: 9483155.
Reynolds TM, et al. National Institute for Health and Clinical Excellence guidelines on preoperative tests: the use of routine preoperative tests for elective surgery. Ann Clin Biochem. 2006 Jan;43(Pt 1):13-6. PMID: 16390604.
Related Resources:
Patient Pamphlet: Lab Tests Before Surgery: When you need them and when you don’t
Toolkit: Drop the Pre-Op – A toolkit for reducing unnecessary visits and investigations in pre-operative clinics