The PENGUIN trial is a 2 x 2 factorial, international pragmatic randomised trial. The trial aims to assess whether preoperative chlorhexidine mouthwash when compared to no-mouthwash-surgery can reduce incidence of post-operative pneumonia (POP) and whether perioperative liberal oxygen versus restrictive oxygen can reduce incidence surgical site infections (SSI) at 30-days among abdominal surgery patients.
Two preliminary economic evaluations will be conducted prior to the clinical trial:
(1) The PENGUIN mouthwash preliminary economic evaluation. POP is associated with high healthcare costs, post-operative adverse events and mortality. The post-operative mortality rates associated with POP are more frequent in low and middle-income countries (LMICs) compared to high income countries (HICs). There is some evidence from studies conducted among cardiac surgery subjects in HICs suggesting that preoperative chlorhexidine mouthwash can reduce the incidence of POP however there is no evidence of it being effective in other income settings and other surgeries. Furthermore, due to the emerging of the corona virus 2019 disease (COVID-19) it is expected that POP rates will be higher during the COVID-19 pandemic period compared to the pre-COVID-19 period.
The preliminary economic evaluation will assess the potential cost-effectiveness of preoperative chlorhexidine mouthwash surgery in reducing POP among abdominal surgery patients when compared to no-mouthwash surgery. A decision model taking the South African health care perspective will be built for the analysis. Model input parameters: costs, probabilities and outcomes will be estimated from literature. The analysis will compare the cost-effectiveness of the intervention in the absence and presence of COVID-19 to identify the impact of COVID-19 on mouthwash cost-effectiveness.
Alongside the trial, the health economics team will also conduct a trial-based economic evaluation to assess the cost-effectiveness of the mouthwash in reducing POP using primary data.
Systematic review: costs of pneumonia following abdominal surgery
The objective of the systematic review is to estimate the costs of post-operative pneumonia among abdominal surgery patients. This information will be important in prioritising healthcare resources by informing healthcare providers and policy makers about the costs that can be saved by reducing post-operative pneumonia incidence. Feeding into the PENGUIN mouthwash preliminary cost-effectiveness analysis, the cost estimates from the review will be used as input parameters in the preliminary model.
(2) The PENGUIN oxygen preliminary economic evaluation. Surgical site infections (SSI) are one of the most common medical care advents events. The world Health Organisation (WHO) recommended perioperative high dose fraction of inspired oxygen as an intervention for reducing SSIs. However, there is mixed evidence on the effectiveness and safety of the intervention compared to using perioperative low dose oxygen concentration. One of the objectives of the PENGUIN trial is to provide evidence whether perioperative high dose oxygen concentration is effective and safe in reducing the incidence of SSIs.
The Global Surgery Collaborative health economics team will conduct a preliminary economic evaluation to evaluate the potential cost-effectiveness of high dose fraction of inspired oxygen in reducing SSIs when compared to low dose fraction of inspired oxygen. The evaluation will estimate the costs associated with delivering high dose compared to low dose fraction of inspired oxygen, SSI rates of the two oxygen concentrations and the identify data gaps as well as uncertainties associated with the input parameters to strengthen health economics data collection during the trial.
Furthermore, a trial based cost-effectiveness analysis will be conducted at the end of the using the decision tree from the preliminary model and primary data collected from the PENGUIN trial.
Training Global Surgery collaborators on health economics
Health economics knowledge is important to program managers, physicians and all healthcare workers in the implementation of programs and projects to ensure that interventions represent efficient use of healthcare resources. The NIHR Global Health Research Unit on Global Surgery organised a Prioritisation Workshop in Accra, Ghana in November, 2019 for countries involved in the Global Surgery Collaboration Initiative.
As part of the workshop the health economics team from Birmingham oriented the participants on fundamentals of health economics. The short training course equipped the participants with knowledge to help them prioritise surgical interventions to fund based on health economics. The training focused on fundamentals of health economics such as scarcity, opportunity cost, economic evaluations alongside clinical trials including costing resource use, using health outcomes especially disability adjusted life years (DALYs) and quality adjusted life years (QALYs), and how to use the costs and outcomes in cost-effectiveness analysis.
Immediately after the Accra workshop a similar workshop was held in Tamale, Ghana, which was attended by anaesthetists, medical doctors, surgeons and Nurses from the Ghana healthcare system.