The Effect of Patient Safety Events on Elective Surgical Patients at US Academic Medical Centers

Research Article

Austin J Clin Med. 2014;1(1): 1003.

The Effect of Patient Safety Events on Elective Surgical Patients at US Academic Medical Centers

Vincent Barba1,*, Maryann Sakmyster2

1Assistant Professor of Medicine and Preventive Medicine, Rutgers NJ Medical School, USA

2University Hospital, New Jersey, USA

*Corresponding author: Vincent Barba, 1Assistant Professor of Medicine and Preventive Medicine, Rutgers NJ Medical School, 150 Bergen Street, Newark, New Jersey, USA

Received: January 02, 2014; Accepted: January 23, 2014; Published:February 14, 2014

Abstract

Objective: To determine the extent of the impact of a patient safety event on outcomes for elective surgical admissions at US academic medical centers.

Methods:The study design was a retrospective cohort analysis. The UHC Clinical Database was used to evaluate inpatients from 106 US academic medical centers. The system was queried for the development of a cohort in which patients admitted for elective surgical procedure did not experience a urgical patient safety event and a cohort in which the patients did experience a surgical patient safety event during their inpatient stay. Outcomes for each cohort were length of stay, costs, 30 day readmissions and inpatient mortality. The UHC risk-adjustment methodology was used to compare observed rates to expected rates of resource utilization and mortality outcomes.

Results: Over 500,000 cases were analyzed. 13,733 cases were found that had experienced a surgical patient safety event during their inpatient stay. The incidence rate of a patient safety event occurring was 26.1/1,000 discharges [2.6%].

The mortality rate, mean length of stay, mean cost and 30 day readmission rate for those patients in the cohort without a post surgery patient safety event occurring was 0.32%, 4.43 days, $17,197 and 8.06%, respectively. The LOS and mortality rates were lower at a 0.01 level of statistical significance than expected. Costs were higher than expected at a 0.01 level of significance.

The mortality rate, mean length of stay, mean cost and 30 day readmission rate for those patients in the cohort with a patient safety event occurring was 9.31%, 15.25 days, $51,500 and 16.24% , respectively. The mean LOS, mean cost and mortality rate were higher at a .01 level of statistical significance than expected.

Conclusion: Higher mortality rates, 30 day readmission rates, mean LOS and cost are associated with the occurrence of a patient safety events among surgical inpatients admitted electively to academic medical centers.

Introduction

Patient safety contributes considerably to resource utilization and mortality in the United States. It has been estimated that adverse events occur in 49 out of 100 patient admissions which amounts to over 18 million patient safety events annually [1]. This costs Americans over 17 billion dollars per year [2]. The death toll from patient safety events has been reported by the Institute of Medicine as up to 98,000 per year [3]. Recent estimates report the death toll may be over four times as high [4].

The academic medical center offers patients innovative medical care for some of the most difficult to treat diseases known to man. Many centers focus on referrals from community physicians for complex medical and surgical problems best solved in the multidisciplinary environs with our nation’s medical school faculty. At these centers we train the physicians of tomorrow as well as the nurses and allied health professionals for the next generation.

This retrospective cohort analysis seeks to determine the outcomes of inpatients at academic medical centers across the US who are admitted for elective surgical procedures and experience a surgical patient safety event (post-surgical or intraoperatively) during the course of their treatment.

Methods

The study design deployed was a retrospective cohort analysis.

The University HealthSystem Consortium’s Clinical Database/Resource Manager v. 1.5.0.10 [UHC CDB/CRM] employing the 2012 UHC risk model was used to analyze information related to patients discharged from 106 US academic medical centers that are part of the Clinical Resource Manager program.

The database was used to review discharges age 18 – 100 years old, (adults) from US academic medical centers in calendar year 2012. Elective inpatient admissions which were assigned a surgical MS-DRG were selected for the analysis. Obstetrical surgeries were excluded from the analysis.

The statistical methods used by UHC for statistical risk modeling to set expected values are logistic regression for mortality and log transformed linear regression for LOS and cost. Outliers at the 99th percentile are excluded from model generation. Models are built on a rolling 2 years of data [5].

The 2012 UHC risk models were built using 114 academic medical center’s inpatient discharge administrative data for Q3 2010 to Q2 2012 as the model population. The data set contains patient-level, ICD-9 diagnosis and procedure codes, patient demographics, charge data and other data elements that are evaluated during the risk modeling for mortality, length of stay and direct cost. UHC technical specifications note that the modeling incorporates the co-morbid conditions that are present at the time of admission so as to minimize the impact of iatrogenic conditions on the risk model generations [5].

A patient safety event was defined as a case which met the profile for AHRQ Patient Safety Indicators [PSI] that capture surgical outcomes: 8, 9, 10, 11, 12, 13, 14, 15. The inpatient mean length of stay, mean cost, 30 day readmission rates and mortality rates were then analyzed and compared to those cases in which a PSI was not assigned.

Cohort 1, Non-PSI, included cases in which no surgical patient safety event occurred.

Cohort 2, PSI, included cases in which a surgical patient safety event occurred.

The incidence per thousand discharges and mortality rates for PSI 8-14, were reported.

The technical specifications for the AHRQ PSI can be found at https://qualityindicators.ahrq.gov/Modules/PSI_TechSpec.aspx

Note: The information contained in this article was based in part on the Clinical Database/Resource Manager (CDB/RM) maintained by the University HealthSystem Consortium (UHC).

Results

526,594 cases discharged from academic medical centers in calendar year 2012 were elective admissions with a surgical procedure. The mean length of stay was 4.71 days, the mean cost was $ 18,093, 30 day readmission rate was 8.25% and the inpatient mortality rate was 0.55%

Table 1 lists the cases with a surgical patient safety event, the incidence rates and inpatient mortality rates. PSI 11, Postoperative Respiratory Failure had the highest occurrence rate and Postoperative Hip Fracture the lowest occurrence rate, 0.02 per 1,000 cases.

Citation: Barba V, Sakmyster M. The Effect of Patient Safety Events on Elective Surgical Patients at US Academic Medical Centers. Austin J Clin Med. 2014;1(1): 1003. ISSN : 2381-9146