Scope of Practice Laws and Anesthesia Complications: No Measurable Impact of Certified Registered Nurse Anesthetist Expanded Scope of Practice on Anesthesia-related Complications.

Background: Scope of practice (SOP) laws governing Certified Registered Nurse Anesthetists (CRNAs) vary by state and drive CRNA practice and reimbursement. Objective: To test whether the odds of an anesthesia complication vary by SOP and delivery model (CRNA only, anesthesiologist only, or mixed anesthesiologist and CRNAs team). Methods: Anesthesia claims and related complications were identified in a large commercial payor database, including inpatient and ambulatory settings. Logit regression models were estimated by setting to determine the impact of SOP and delivery model on the odds of an anesthesia-related complication, while controlling for patient characteristics, patient comorbidities, procedure and procedure complexity, and local area economic factors. Results: Overall, 8 in every 10,000 anesthesia-related procedures had a complication. However, complications were 4 times more likely in the inpatient setting (20 per 10,000) than the outpatient setting (4 per 10,000). In both settings, the odds of a complication were found to differ significantly with patient characteristics, patient comorbidities, and the procedures being administered. The odds of an anesthesia-elated complication are particularly high for procedures related to childbirth. However, complication odds were not found to differ by SOP or delivery model. Conclusions: Our research results suggest that there is strong evidence of differences in the likelihood of anesthesia complications by patient characteristics, patient comorbidities, and the procedures being administered, but virtually no evidence that the odds of a complication differ by SOP or delivery model.