Importance: Deep sedation for endoscopic procedures has become an increasingly used option but, because of impairment in patient response, this technique also has the potential for a greater likelihood of adverse events. The incidence of these complications has not been well studied at a population level.
Design: Population-based study.
Setting and participants: Using a 5% random sample of cancer-free Medicare beneficiaries who resided in one of the regions served by a SEER (Surveillance, Epidemiology, and End Results) registry, we identified all procedural claims for outpatient colonoscopy without polypectomy from January 1, 2000, through November 30, 2009.
Intervention: Colonoscopy without polypectomy, with or without the use of deep sedation (identified by a concurrent claim for anesthesia services).
Main outcome measures: The occurrence of hospitalizations for splenic rupture or trauma, colonic perforation, and aspiration pneumonia within 30 days of the colonoscopy.
Results: We identified a total of 165 527 procedures in 100 359 patients, including 35 128 procedures with anesthesia services (21.2%). Selected postprocedure complications were documented after 284 procedures (0.17%) and included aspiration (n = 173), perforation (n = 101), and splenic injury (n = 12). (Some patients had >1 complication.) Overall complications were more common in cases with anesthesia assistance (0.22% [95% CI, 0.18%-0.27%]) than in others (0.16% [0.14%-0.18%]) (P < .001), as was aspiration (0.14% [0.11%-0.18%] vs 0.10% [0.08%-0.12%], respectively; P = .02). Frequencies of perforation and splenic injury were statistically similar. Other predictors of complications included age greater than 70 years, increasing comorbidity, and performance of the procedure in a hospital setting. In multivariate analysis, use of anesthesia services was associated with an increased complication risk (odds ratio, 1.46 [95% CI, 1.09-1.94]).
Conclusions and relevance: Although the absolute risk of complications is low, the use of anesthesia services for colonoscopy is associated with a somewhat higher frequency of complications, specifically, aspiration pneumonia. The differences may result in part from uncontrolled confounding, but they may also reflect the impairment of normal patient responses with the use of deep sedation.