title: Is regional anesthesia associated with reduced PACU length of stay?: A retrospective analysis from a tertiary medical center.
abstract: BACKGROUND
  Postanesthesia care is a costly component of overall surgical care. In the ambulatory setting, regional anesthesia has been shown for multiple surgical procedures to either decrease postanesthesia care unit (PACU) length of stay (LOS) or completely bypass it altogether. This has not been demonstrated in a large hospital setting with a complex surgical case mix.
  
  
  OBJECTIVE
  We therefore determined whether regional anesthesia was associated with a reduced PACU LOS among patients undergoing inpatient and outpatient surgery in a large tertiary-care teaching hospital. Secondary study questions included risk factors for longer PACU LOS and any possible interaction between regional and general anesthesia as it might have affected PACU LOS.
  
  
  METHODS
  We performed a matched retrospective study on patients who had surgery at our institution and were admitted to the PACU immediately after leaving the operating room. We analyzed between January 1, 2005, and January 1, 2013, with one cohort receiving regional anesthesia, with or without general anesthesia, and the other receiving no regional anesthesia. We measured the association between regional anesthesia and time to successful PACU discharge using a Cox multivariate proportional-hazards model.
  
  
  RESULTS
  After controlling for potentially confounding variables, including patient age, American Society of Anesthesiologists' physical classification, and duration of surgery (using multivariate analysis), there was no difference in the time to successful PACU discharge between patients who received regional anesthesia and those who did not. However, when compared to those who received general anesthesia, regional anesthesia was associated with decreased PACU LOS. Further, there was significant effect modification between regional and general anesthesia; patients who received both regional and general were more likely to be successfully discharged faster from the PACU than patients who received only general anesthesia (hazard ratio = 1.50, 95% CI = 1.46-1.55, p < 0.001).
  
  
  CONCLUSIONS
  We demonstrated that independently, regional anesthesia is not associated with a reduced PACU LOS in an unselected population at a large tertiary-care hospital, but regional is favored when compared to general anesthesia. Whether the differences are clinically important, and in what procedures they are most pronounced, would be reasonable questions for future prospective comparative trials.
  
  
  METHODS
  Level III, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Vanderbilt University Medical Center, 1301 Medical Center Drive #4648, Nashville, TN, 37237, USA, john.corey@vanderbilt.edu.
authors.forename: John M
authors.initials: JM
authors.lastname: Corey
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Bulka
authors.forename: Jesse M
authors.initials: JM
authors.lastname: Ehrenfeld
mesh_terms: D000328:Adult; D000762:Anesthesia Recovery Period; D000765:Anesthesia, Conduction / Q000009:adverse effects; D000768:Anesthesia, General / Q000009:adverse effects; D005260:Female; D006784:Hospitals, Teaching; D006801:Humans; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010351:Patient Discharge; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D013514:Surgical Procedures, Operative; D013714:Tennessee; D062606:Tertiary Care Centers; D013997:Time Factors