Temporal changes in survival after cardiac surgery are associated with the thirty-day mortality benchmark.
OBJECTIVE
To assess the hypothesis that postoperative survival exhibits heterogeneity associated with the timing of quality metrics.


METHODS
Retrospective observational study using the Nationwide Inpatient Sample from 2005 through 2009.


METHODS
Survival analysis was performed on all admission records with a procedure code for major cardiac surgery (n = 595,089). The day-by-day hazard function for all-cause in-hospital mortality at 1-day intervals was analyzed using joinpoint regression (a data-driven method of testing for changes in hazard).


METHODS
A comprehensive analysis of a publicly available national administrative database was performed.


RESULTS
Statistically significant shifts in the pattern of postoperative mortality occurred at day 6 (95 percent CI = day 5-8) and day 30 (95 percent CI = day 20-35).


CONCLUSIONS
While the shift at day 6 plausibly can be attributed to the separation between routine recovery and a complicated postoperative course, the abrupt increase in mortality at day 30 has no clear organic etiology. This analysis raises the possibility that this observed shift may be related to clinician behavior because of the use of 30-day mortality as a quality metric, but further studies will be required to establish causality.
Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD.
Bryan G
BG
Maxwell
Jim K
JK
Wong
D Craig
DC
Miller
Robert L
RL
Lobato
D019985:Benchmarking; D006348:Cardiac Surgical Procedures / Q000401:mortality*; D002318:Cardiovascular Diseases / Q000401:mortality* / Q000601:surgery*; D002423:Cause of Death / Q000639:trends*; D017052:Hospital Mortality / Q000639:trends*; D006801:Humans; D007902:Length of Stay; D016015:Logistic Models; D011183:Postoperative Complications / Q000401:mortality*; D012189:Retrospective Studies; D016019:Survival Analysis; D013997:Time Factors
Cardiac surgery; Hawthorne effect; Nationwide Inpatient Sample; quality metrics; surgical outcomes