Jonathan D Bloom, MD, Santosh J Agarwal, BPharm MS, Mary G Erslon, RN MS MBA, Michael L Mestek, PhD, Douglas M Hansell, MD MPH, Ross D Segan, MD. Covidien
Introduction: The objective of this study was to examine the incidence of, risk factors for and economic impact of respiratory failure (RF) after abdominal surgery. We hypothesized that patients with conditions suggestive of hypoventilation (sleep-disordered breathing [SDB], obesity, and administration of naloxone) are more likely to develop RF and thus incur greater hospitalization costs.
Postoperative Respiratory Failure (PRF) is a potentially life-threatening complication in surgical care. The Agency for Healthcare Research and Quality (AHRQ) identified Postoperative Respiratory Failure as a Patient Safety Indicator in 2009, and the Centers for Medicare and Medicaid Services (CMS) are now proposing the adoption of PRF into the 2012 Reporting Hospital Quality Data for Annual Payment Update program (RHQDAPU). Understanding the risks for RF post-abdominal surgery may help identify patients appropriate for increased observation and monitoring.
Methods: We used the Premier Perspective® Database for 2009 to identify all adult inpatient surgical MS-DRG discharges with diseases and disorders related to the hepatobiliary, pancreatic and digestive systems (Perspective® is a registered trademark of Premier, Inc.). ICD-9-CM diagnosis codes 518.81 and 799.1x were used to identify RF. We compared the incidence, mortality rates, total costs and length of stay among those with and without RF. We used multivariate logistic regression to estimate the adjusted odds of development of RF, accounting for age, race, sex, geographic region, components of the Charlson comorbidity index and admitting status. Obesity, SDB and naloxone administration were identified as a priori predictors of RF. National projections for the year 2009 were made using Premier supplied projection weights.
Results: Of the 197,216 discharges that met the inclusion criteria, 4,668 (2.4%) developed RF. RF was associated with increased mortality (26% vs. 1%, p<0.0001), length of stay (17d vs. 6d, p<0.0001), and total costs ($48,775 vs. $13,823, p<0.0001), compared to those without RF. Projecting to national levels there were approximately 29,700 cases of RF post-abdominal surgery, adding over 348,000 hospital days, and $1.05 billion in added costs.
SDB (OR: 1.34, 95% CI: 1.20-1.50) and naloxone administration (OR: 3.52, 95% CI: 3.18-3.91) were significant independent risk factors for RF. Obesity was not a significant risk factor for RF in our sample. Presence of comorbidities significantly increased the risk of RF, particularly moderate/severe liver disease (324% increased risk), peptic ulcers (230%), congestive heart failure (178%), paralysis (hemiplegia or paraplegia) (158%), COPD (87%), chronic renal failure (80%), cerebrovascular disease (61%), moderate liver disease (43%), myocardial infarction (41%), metastatic solid tumor (40%), malignancy (25%) and peripheral vascular disease (20%).
Conclusions: RF post-abdominal surgery is associated with a significant increase in mortality, costs, and length of stay compared to discharges without RF. SDB and naloxone administration are independently associated with increased risk for RF in abdominal surgery patients. Other systemic conditions including hepatic, ulcer, cardiopulmonary, renal and cerebrovascular diseases are also significant risk factors for the development of RF. Better strategies for prevention of, monitoring for and management of RF in post-abdominal surgery patients could lead to improved outcomes and substantial cost savings for hospitals.
Program Number: P441