Volume 55 | Number 1 | February 2020

Abstract List

Matthew Baird PhD, John M. O'Donnell DRPH, MSN, RN, CRNA, CHSE, FSSH, Grant R. Martsolf Ph.D., M.P.H., R.N.


To estimate the impact of opting‐out from Medicare supervision requirements for certified registered nurse anesthetists (CRNAs) on anesthesiologists' work patterns.

Data Sources/Study Setting

Secondary data from two national surveys of anesthesiologists and the Area Health Resource File.

Study Design

We use a matching difference‐in‐difference regression which contrasts the change in work patterns for anesthesiologists in California, which dropped supervision requirements, to the change for similar anesthesiologists. Key outcome variables include the number of weekly hours worked, the type of work done, and type of care delivery teams.

Data Collection/Extraction Methods

Self‐reported national survey data drawn from members of the American Society of Anesthesiologists.

Principal Findings

Anesthesiologists in California saw no change in time spent working or time spent supervising CRNAs. There was a decrease in direct care clinical work hours along with a shift in working more in intraoperative care, a decrease in postoperative care, and an increase in the percentage of cases supervising residents.


Anesthesiologists had small but real responses to California’s decisions to opt‐out of the physician supervision requirement for CRNAs, doing more work in intraoperative care and less outside of the operating room. Total hours worked saw no change.