Protocol for a parallel economic evaluation of a trial comparing two surgical strategies in severe complicated intra-abdominal sepsis: the COOL-cost study

Establishment and evaluation of an improved rat model of open abdomen

INTRODUCTION

This study aimed to establish an animal model of open abdomen (OA) through temporary abdominal closure via different techniques.

METHODS

Adult male Sprague-Dawley rats were randomly divided into three groups: group A (OA with polypropylene mesh alone); group B (OA with polypropylene mesh combined with a patch); and group C (OA with polypropylene mesh and a sutured patch). Vital signs, pathophysiological changes, and survival rates were closely monitored in the rats for 7 days after surgery. Abdominal X-rays and histopathological examinations were performed to assess abdominal organ changes and wound healing.

RESULTS

The results showed no significant difference in mortality rates among the three groups (p > 0.05). However, rats in group B exhibited superior overall condition, cleaner wounds, and a higher rate of wound healing compared to the other groups (p < 0.05). Abdominal X-rays indicated that varying degrees of distal intestinal obstruction in all groups. Histopathological examinations revealed fibrous hyperplasia, inflammatory cell infiltration, neovascularization, and collagen deposition in all groups. Group B demonstrated enhanced granulation tissue generation, neovascularization, and collagen deposition compared to the other groups (p < 0.05).

CONCLUSIONS

Polypropylene mesh combined with patches is the most suitable method for establishing an animal model of OA. This model successfully replicated the pathological and physiological changes in postoperative patients with OA, specifically the progress of abdominal skin wound healing. It provides a practical and reliable animal model for OA research.

Source control in emergency general surgery: WSES, GAIS, SIS-E, SIS-A guidelines

Intra-abdominal infections (IAI) are among the most common global healthcare challenges and they are usually precipitated by disruption to the gastrointestinal (GI) tract. Their successful management typically requires intensive resource utilization, and despite the best therapies, morbidity and mortality remain high. One of the main issues required to appropriately treat IAI that differs from the other etiologies of sepsis is the frequent requirement to provide physical source control. Fortunately, dramatic advances have been made in this aspect of treatment. Historically, source control was left to surgeons only. With new technologies non-surgical less invasive interventional procedures have been introduced. Alternatively, in addition to formal surgery open abdomen techniques have long been proposed as aiding source control in severe intra-abdominal sepsis. It is ironic that while a lack or even delay regarding source control clearly associates with death, it is a concept that remains poorly described. For example, no conclusive definition of source control technique or even adequacy has been universally accepted. Practically, source control involves a complex definition encompassing several factors including the causative event, source of infection bacteria, local bacterial flora, patient condition, and his/her eventual comorbidities. With greater understanding of the systemic pathobiology of sepsis and the profound implications of the human microbiome, adequate source control is no longer only a surgical issue but one that requires a multidisciplinary, multimodality approach. Thus, while any breach in the GI tract must be controlled, source control should also attempt to control the generation and propagation of the systemic biomediators and dysbiotic influences on the microbiome that perpetuate multi-system organ failure and death. Given these increased complexities, the present paper represents the current opinions and recommendations for future research of the World Society of Emergency Surgery, of the Global Alliance for Infections in Surgery of Surgical Infection Society Europe and Surgical Infection Society America regarding the concepts and operational adequacy of source control in intra-abdominal infections.

The unrestricted global effort to complete the COOL trial

BACKGROUND

Severe complicated intra-abdominal sepsis (SCIAS) has an increasing incidence with mortality rates over 80% in some settings. Mortality typically results from disruption of the gastrointestinal tract, progressive and self-perpetuating bio-mediator generation, systemic inflammation, and multiple organ failure. A further therapeutic option may be open abdomen (OA) management with negative peritoneal pressure therapy (NPPT) to remove inflammatory ascites and attenuate the systemic damage from SCIAS, although there are definite risks of leaving the abdomen open whenever it might possibly be closed. This potential therapeutic paradigm is the rationale being assessed in the Closed Or Open after Laparotomy (COOL trial) ( https://clinicaltrials.gov/ct2/show/NCT03163095 ). Initially, the COOL trial received Industry sponsorship; however, this funding mandated the use of a specific trademarked and expensive NPPT device in half of the patients allocated to the intervention (open) arm. In August 2022, the 3 M/Acelity Corporation without consultation but within the terms of the contract canceled the financial support of the trial. Although creating financial difficulty, there is now no restriction on specific NPPT devices and removing a cost-prohibitive intervention creates an opportunity to expand the COOL trial to a truly global basis. This document describes the evolution of the COOL trial, with a focus on future opportunities for global growth of the study.

METHODS

The COOL trial is the largest prospective randomized controlled trial examining the random allocation of SCIAS patients intra-operatively to either formal closure of the fascia or the use of the OA with an application of an NPPT dressing. Patients are eligible if they have free uncontained intraperitoneal contamination and physiologic derangements exemplified by septic shock OR severely adverse predicted clinical outcomes. The primary outcome is intended to definitively inform global practice by conclusively evaluating 90-day survival. Initial recruitment has been lower than hoped but satisfactory, and the COOL steering committee and trial investigators intend with increased global support to continue enrollment until recruitment ensures a definitive answer.

DISCUSSION

OA is mandated in many cases of SCIAS such as the risk of abdominal compartment syndrome associated with closure, or a planned second look as for example part of "damage control"; however, improved source control (locally and systemically) is the most uncertain indication for an OA. The COOL trial seeks to expand potential sites and proceed with the evaluation of NPPT agnostic to device, to properly examine the hypothesis that this treatment attenuates systemic damage and improves survival. This approach will not affect internal validity and should improve the external validity of any observed results of the intervention.

TRIAL REGISTRATION

National Institutes of Health ( https://clinicaltrials.gov/ct2/show/NCT03163095 ).

Identifying indicators and evaluation steps with suggestions for improving trauma care in Iran: experts' perspective

BACKGROUND

Trauma is one of the major causes of mortality across the world. Trauma patients have critical status and need timely, adequate, and organized care. The different consequences of trauma care among service centers around the world and even within a country revealed the need for careful evaluation. This study was designed and executed to collect experts' opinions on the evaluation steps, related indicators, and improvement strategies in trauma care.

METHODS

This qualitative study was based on a conventional content analysis approach. 2 focus group discussions (FGD) with 6 participants per FGD and 16 face-to-face in-depth interviews were conducted to collect the required information (from September 2018 to early 2019). Participants were selected through the purposive sampling method. The experts' viewpoints were classified by the main and sub themes.

RESULTS

Four basic themes extracted from the interviews and focus group discussions including, trauma care importance (sub-themes: the involved individuals' being young and productive and the effectiveness of trauma care); trauma care indicators (sub-themes: pre-hospital indicators, in-hospital indicators, and post-hospital indicators); stages of trauma care evaluation (sub-themes: evaluation prerequisites, finalization of indicators before the evaluation, determining evaluation time scope, determining evaluation dimensions, external and internal evaluation and use of evaluation results); trauma care improvement (sub-themes: balancing workload in trauma centers, enhancement of information system, considering extra-organizational dimensions in trauma care and empowerment of trauma care providers).

CONCLUSIONS

According to experts' viewpoints, trauma is a very important issue, because it involves young people. They believed that having indicators covering all aspects of care assist health managers and policymakers to understand under-standard performance. These indicators should be used in the form of a specific evaluation program and related to Iran context. Besides, reforming macro policies, planning, development of infrastructures, and education was some recommendations of experts to improve trauma care.

Cost-effectiveness of guideline-based stepped and collaborative care versus treatment as usual for patients with depression - a cluster-randomized trial

BACKGROUND

Depression is associated with major patient burden. Its treatment requires complex and collaborative approaches. A stepped care model based on the German National Clinical Practice Guideline "Unipolar Depression" has been shown to be effective. In this study we assess the cost-effectiveness of this guideline based stepped care model versus treatment as usual in depression.

METHODS

This prospective cluster-randomized controlled trial included 737 depressive adult patients. Primary care practices were randomized to an intervention (IG) or a control group (CG). The intervention consisted of a four-level stepped care model. The CG received treatment as usual. A cost-utility analysis from the societal perspective with a time horizon of 12 months was performed. We used quality-adjusted life years (QALY) based on the EQ-5D-3L as effect measure. Resource utilization was assessed by patient questionnaires. Missing values were imputed by 'multiple imputation using chained equations' based on predictive mean matching. We calculated adjusted group differences in costs and effects as well as incremental cost-effectiveness ratios. To describe the statistical and decision uncertainty cost-effectiveness acceptability curves were constructed based on net-benefit regressions with bootstrapped standard errors (1000 replications). The complete sample and subgroups based on depression severity were considered.

RESULTS

We found no statically significant differences in costs and effects between IG and CG. The incremental total societal costs (+€5016; 95%-CI: [-€259;€10,290) and effects (+ 0.008 QALY; 95%-CI: [- 0.030; 0.046]) were higher in the IG in comparison to the CG. Significantly higher costs were found in the IG for outpatient physician services and psychiatrist services in comparison to the CG. Significantly higher total costs and productivity losses in the IG in comparison to the CG were found in the group with severe depression. Incremental cost-effectiveness ratios for the IG in comparison to the CG were unfavourable (complete sample: €627.000/QALY gained; mild depression: dominated; moderately severe depression: €645.154/QALY gained; severe depression: €2082,714/QALY gained) and the probability of cost-effectiveness of the intervention was low, except for the group with moderate depression (ICER: dominance; 70% for willingness-to-pay threshold of €50,000/QALY gained).

CONCLUSIONS

We found no evidence for cost-effectiveness of the intervention in comparison to treatment as usual.

TRIAL REGISTRATION

NCT, NCT01731717 . Registered 22 November 2012 - Retrospectively registered.