Impact of a surgical safety checklist on safety culture, morbidity, and mortality. A stepped-wedge cluster randomised controlled trial

Abstract

Introduction: The incidence of in-hospital adverse events is estimated to occur in approximately 1 out of 10 patients. Events happening during surgical procedures contribute up to 60%, and of these, more than half are considered to be preventable. Communication breakdowns have been identified as an important contributor to errors. The introduction of surgical safety checklists that are intended to improve teamwork and communication decreases both morbidity and mortality. It has been hypothesised that improved patient outcomes result from changes in safety culture. Thus, randomised controlled studies are warranted in order to investigate whether the use of checklists are responsible for positive effects on patient outcomes. Aims: 1. In the study reported in Paper 1, we aimed to (1) validate the psychometric properties of the Hospital Survey on Patient Safety Culture (HSOPS) in a surgical environment, and (2) to compare results from its use on the safety culture in healthcare personnel in different countries. 2. In the study reported in Paper 2, we aimed to determine whether use of the World Health Organization (WHO) Surgical Safety Checklist (SSC) positively affects safety culture. We used the HSOPS to assess this. 3. In the study reported in Paper 3, we aimed to determine whether the use of the WHO SSC positively affects patient outcomes, reducing morbidity, mortality, and length of hospital stay. Methods: In the first study, a cross-sectional survey using the HSOPS was conducted in 575 surgical personnel at Haukeland University Hospital in 2009. Surgeons, operating theatre nurses, anaesthetists, nurse anaesthetists, and ancillary personnel were included. We used explorative factor analysis to examine the applicability and the internal consistency of the HSOPS factor structure in operating theatre settings. This survey constituted the baseline measure in the second study. In the second study, the WHO SSC was introduced after the baseline survey was completed, along with an educational programme that provided the rationale for why and how the checklist was to be used. The implementation was carried out with a stepped-wedge cluster, randomised controlled design and was conducted in three surgical specialties (orthopaedic, cardiothoracic, and neurosurgery) at Haukeland University Hospital; the order of implementation for the three specialties was randomised. The control group comprised surgical personnel from ear, nose, and throat; maxillofacial; plastic; endocrine; urological; gastrointestinal; obstetric; and gynaecological surgical specialities. In this study, the controls did not receive the WHO SSC intervention during the study period. A total of 349 participants responded at baseline assessment, and 292 responded at post-intervention assessment. The primary outcome measure was the values of the twelve safety culture factors of the HSOPS, and the secondary outcome measure was the degree of WHO SSC compliance. In the third study, the WHO SSC was implemented using a stepped-wedge cluster randomised controlled design in five surgical specialties. Three (orthopaedic, cardiothoracic, and neurosurgery) were from Haukeland University Hospital and two (urology and general surgery) were from Førde Central Hospital, with a total of 5,295 surgical procedures included. The intervention was randomised and conducted until all five specialties had received it. We examined whether using the WHO SSC affects in-hospital complications, as measured by ICD-10 codes, length of stay, and postsurgical mortality (up to 30 days). Results: In the first study, the HSOPS was determined to be valid for measuring safety culture in an operating theatre setting, with internal consistency and Cronbach’s alpha values ranging from 0.59 to 0.85. A twelve-factor structure of the survey instrument was supported.In the second study, the WHO SSC intervention had a significant impact on two safety culture factors—‘frequency of events (near misses) reported’ and ‘adequate staffing’—in the intervention group, with regression coefficients of -0.25 (95% CI, - 0.47 to -0.07) and 0.21 (95% CI, 0.07 to 0.35), respectively. Between baseline and post-intervention assessments, there was a significant improvement in the factors ‘hospital management promoting safety’ and ‘handoffs and transitions’, with regression coefficients of 0.12 (95% CI, 0.04 to 0.20) and 0.08 (95% CI, 0.01 to 0.14), respectively. In the third study, we observed a significant decrease in complications from 19.9% to 11.5% in 2,212 surgical procedures before and 2,263 after implementation of the WHO SSC (P<0.001). The absolute risk reduction (ARR) was 8.4 (95% CI, 6.3 to 10.5). Adjusted for possible confounding factors, the WHO SSC effect on complications remained significant, with an odds ratio of 1.95 (95% CI, 1.59 to 2.40). The checklist prevented one or more complications when used in twelve surgical procedures. Mean length of stay decreased by 0.8 days (95% CI, 0.11 to 1.43). Although in-hospital mortality decreased significantly from 1.9% to 0.2% in the central community hospital, the overall reduction of mortality (from 1.6% to 1.0%) across hospitals was not statistically significant. Conclusions: The HSOPS was determined to be valid for use in this specific clinical setting. The WHO SSC intervention had a rather limited effect on the overall safety culture, but significantly changed perceptions of surgical professionals in the intervention group on two factors, ‘frequency of events reported’ and ‘adequate staffing’. The steppedwedge cluster randomised implementation of the WHO SSC was associated with robust reduction in morbidity and length of stay, and some reduction in mortality.