STOP? II trial: Cluster randomized clinical trial to test the implementation of a toolbox for structured communication in the operating room to reduce surgical mortality

Abstract

Background and rationale: Surgical care, which is performed by intensely interacting multidisciplinary teams of surgeons, anesthetists and nurses remains associated with significant morbidity and mortality. Intraoperative communication has been shown to be associated with surgical outcomes, but tools that ensure efficient intraoperative communication are lacking.We have developed the StOP? protocol in order to ensure structured intraoperative communication. Before critical phases of the operation, the responsible surgeon initiates and leads the StOP? protocol. During the STOP? protocol, the surgeon informs about the progress of the surgery (Status), next steps and proximal goals (Objectives), and possible problems (Problems), and all team members are encouraged to voice their observations and ask questions (?).In a multicenter study using a before-after design, we observed outcomes from 8256 patients from 4 different centers performing general surgery. There were two primary outcome parameters - surgical site infections, which was used for the power calculation, and mortality. Whereas there was no effect of StOP? on surgical site infections, we observed a significant reduction in mortality. These results yield a strong basis for the hypothesis that the introduction and application of the StOP? protocol reduces surgical mortality in a randomized controlled trial. Aims: Determine in a cluster randomized clinical trial if the introduction of the StOP? protocol reduces overall 30-day mortality across different surgical specialties. Methods: Study design: Cluster randomized clinical trial by randomizing independent surgeons. Intervention: Intraoperative briefings according to the StOP? protocol. Inclusion criteria for clusters: Board-certified surgeons with specialization in one of the following disciplines: general, visceral, thoracic, vascular surgery, surgical urology or gynaecology. Expected operation volume of 30 eligible operations within four months. Inclusion criteria for operations: All operations performed by a cluster (surgeon) during the cluster-specific time-period. Primary end point: Patient death 30 days after surgery. Secondary end points: Unplanned reoperation, unplanned readmission within 30 days post-surgery, length of hospital stay, patient’s health-related quality of life and activities of daily living.Sample size calculation is based on the following assumptions from the StOP? before-after study: Intracluster correlation coefficient (ICC) of 0.024; event rate (30-day mortality) of 1.8% in the control group. The target treatment effect not to be missed is an odds ratio of 0.5, i.e. to reduce mortality in the StOP? arm to 0.9%. With 400 clusters overall (with 1:1 allocation i.e. 2x200) and an average size of 24 patients per cluster, we will achieve 84% power at a significance level of 0.05 (two-sided). The target average cluster size is fixed at 30 procedures. This sample size allows for varying cluster sizes to accommodate differences in surgery volume across clusters. Therefore, a minimum 14,000 procedures will be enrolled overall. Duration of the study: Recruitment per cluster is 4 months; surgeons within a department are recruited together. Follow-up for each patient is 30 days. Because of the training need, the hospitals will start the inclusion of surgeons and patients sequentially. We expect that recruitment of surgeons and patients will be completed after approximately 42 months. Significance of the study: The introduction of checklists prior to an operation has been shown to be beneficial. However, the structure of communication within the surgical team during an operation has not been sufficiently addressed yet. Based on existing results of our study (StOP? I study), we hypothesize that the intervention reduces overall mortality after surgery. Such a reduction of surgical mortality and morbidity would be achieved at very low cost.