Purpose: Preoperative investigations are frequently ordered according to care maps or protocols. We hypothesized that selective ordering of investigations by anesthesiology staff would reduce the number and cost of testing.
Methods: Prospective descriptive double cohort study carried out over 17 weeks in a tertiary care preadmission clinic. In Group 1, testing followed usual practice (based on standing preoperative orders) while in Group 2 testing was initiated only on the order of an attending anesthesiologist or anesthesiology resident. Postoperative complications were categorized and confirmed by an internist blinded to group assignment. Fisher's exact test, Chi-square and Student's t test were used to compare the groups as appropriate. Statistical significance was inferred at P < 0.05.
Results: Data were obtained from 507 patients in Group 1 and 431 patients in Group 2. Demographics and ASA risk score were similar in both groups. The mean number of tests ordered did not differ between groups. The mean cost of investigations was reduced from 124 dollars in Group 1 to 95 dollars in Group 2 (P < 0.05). If data for patients assessed by staff anesthesiologists only were considered, the mean cost of testing was reduced to 73 dollars. The number and cost of tests ordered by anesthesia residents were similar to that in Group 1. More complications were noted in Group 2, but these did not appear to be related to the altered test ordering practice.
Conclusion: Selective test ordering by staff anesthesiologists reduces the number and cost of preoperative investigations. Educational efforts should be directed towards improving resident and staff preoperative test ordering practices.