Variation in outcomes of cardiac surgery at a regional hospital

The cardiac surgical unit of a regional hospital had always recognised variation in outcomes as a priority area to monitor. It is one of 61 units that contribute data on patient care and outcomes to the Australian and New Zealand Society of Cardiac and Thoracic Surgeons' (ANZSCTS) Cardiac Surgery Database.

The ANZSCTS Database monitors data on five risk-adjusted or unadjusted key performance indicators identified as priority areas by the ANZSCTS Database Steering Committee. The unit receives quarterly reports from the ANZSCTS Database that allow it to monitor its outcomes in key performance indicators relative to other units and benchmarks.

At one of its regular quarterly reviews of outcomes, the ANZSCTS Database Steering Committee determined that, using data analysed over a rolling 36-month period, the cardiac unit was an outlier for return to theatre for bleeding after isolated coronary artery bypass surgery.

The steering committee alerted the director of the cardiac surgery unit and asked him to investigate.

On initial investigation, the director of the cardiac surgery unit noted that there had been some errors when the data were sent to the database. The hospital corrected the data and sent it back to the database, but also started the process of reviewing patient case notes to identify any potential issues with the care patients had received. The staff at the ANZSCTS database undertook a reanalysis using the corrected data, and found that the unit was still an outlier for return to theatre for bleeding.

The steering committee wrote back to the director of the cardiac surgery unit, and included the director of surgery and head of clinical risk, to provide updated results and analyses to help the hospital investigate the potential reasons for this result. They also provided a list of other factors not collected by the database to aid the local investigation of the rate of return to theatre for bleeding.

The unit director’s investigation revealed underlying problems with aspects of surgical technique. Some consultant staff were also not supervising junior staff throughout all aspects of the surgical procedure. He concluded that these two factors had led to the high rates of return to theatre for bleeding. He discussed these findings with the hospital executive, informed the ANSZCTS Database Steering Committee of the results of his investigations and provided them with an action plan aimed at remedying the problem.

The director met with all of the unit’s surgeons to agree on changes to surgical technique and equipment. They took a multidisciplinary approach with the anaesthetists and intensive care unit to secure haemostasis, as well as increased supervision of junior staff in surgery. The hospital executive informed its quality committee of the report from the database steering committee, and of the subsequent investigation and the actions taken by the cardiac unit. A progress report on the actions, along with relevant indicators, was made a regular item on the quality committee agenda.

Over the next few months the data on return to theatre for bleeding improved and the ANSZCTS database reported that the unit was no longer an outlier. The director of the cardiac surgery unit and the quality committee believed that the changes implemented at the hospital had led to the improvement and monthly reporting to the quality committee ceased.

Several months later, on reviewing the hospital data, the ANZSCTS Database Steering Committee noted that the hospital had reverted to outlier status for the return to theatre for bleeding indicator.

The database steering committee again informed the director of the cardiac surgery unit of the results. The unit investigated whether the previously proposed changes had been adhered to and confirmed that practice had improved. Every adverse event was discussed at monthly surgeon meetings as well as reviewed at four monthly audits. There was ongoing vigilance around the causes and events associated with bleeding and it was acknowledged by the hospital and the Database Steering Committee that the results can fluctuate during a period of change. The unit was not an outlier in the following quarter.

If the unit had been unable to find the source of their increased incidence of return to theatre for bleeding, the next step would have been for the Peer Review and Quality Assurance Committee of the ANZSCTS to work with the hospital to address the issue.

The unit has maintained the improvements and has not been an outlier for any subsequent period.