Understanding Variation in In-hospital Mortality After Major Surgery in the United States

Abstract

Objectives: We aimed to quantify the contributions of patient characteristics (PC), hospital structural characteristics (HC), and hospital operative volumes (HOV) to in-hospital mortality (IHM) after major surgery in the United States (US). Background: The volume-outcome relationship correlates higher HOV with decreased IHM. However, IHM after major surgery is multifactorial, and the relative contribution of PC, HC, and HOV to IHM after major surgery is unknown. Study Design: Patients undergoing major pancreatic, esophageal, lung, bladder, and rectal operations between 2006 and 2011 were identified from the Nationwide Inpatient Sample linked to the American Hospital Association survey. Multilevel logistic regression models were constructed using PC, HC, and HOV to calculate attributable variability in IHM for each. Results: Eighty thousand nine hundred sixty-nine patients across 1025 hospitals were included. Postoperative IHM ranged from 0.9% for rectal to 3.9% for esophageal surgery. Patient characteristics contributed most of the variability in IHM for esophageal (63%), pancreatic (62.9%), rectal (41.2%), and lung (44.4%) operations. HOV explained < 25% of variability for pancreatic, esophageal, lung, and rectal surgery. HC accounted for 16.9% and 17.4% of the variability in IHM for esophageal and rectal surgery. Unexplained variability in IHM was high in the lung (44.3%), bladder (39.3%), and rectal (33.7%) surgery subgroups. Conclusions: Despite recent policy focus on the volume-outcome relationship, HOV was not the most important contributor to IHM for the major organ surgeries studied. PC remains the largest identifiable contributor to hospital mortality. Quality improvement initiatives should emphasize patient optimization and structural improvements, in addition to investigating the yet unexplained sources contributing to IHM.

Variation in Hospital Mortality After Complex Cancer Surgery: Patient, Volume, Hospital or Social Determinants?

“…The current study builds on previous work from Martins et al that examined variations in hospital mortality rates among a 2006–2011 surgical cohort, by exploring the role of additional contributors such as social determinants alongside patient- and hospital-level characteristics among a high-risk cancer surgery cohort during a more recent time period (2010–2020). 26 Similar to the previous study, we noted that patient-level factors were the single most important contributor to IHM across hospitals in California, thereby highlighting the importance of risk identification, stratification and mitigation to improve postoperative outcomes. While the urgency associated with many surgical procedures often limits the potential for substantial improvements in patient functional status and health before surgery, the rapid rise in utilization of neoadjuvant therapy among cancer patients may provide a window of opportunity.…”

“…To ensure fair comparison among hospitals, IHM rates were reliability-adjusted, ordered based on increasing IHM rates, and subsequently divided into tertiles (low: <33rd percentile; medium: 33rd to 66th percentile; and high: > 66th percentile) based on a priori cut-offs to allow for adequate power in the analyses. 26 , 27 Reliability adjustment was used to reduce statistical ‘noise’ to allow for more accurate comparisons between facilities reporting risk-adjusted hospital outcomes. 27 Mortality groups were calculated for each individual operation (i.e., esophagectomy [ES], pneumonectomy [PN], pancreatectomy [PD], and proctectomy [PR]).…”