Complex Ventral Hernia Repair Using Components Separation With or Without Biologic Mesh: A Cost-Utility Analysis

Clinical effectiveness and cost-effectiveness of emergency surgery for adult emergency hospital admissions with common acute gastrointestinal conditions: the ESORT study

Background

Evidence is required on the clinical effectiveness and cost-effectiveness of emergency surgery compared with non-emergency surgery strategies (including medical management, non-surgical procedures and elective surgery) for patients admitted to hospital with common acute gastrointestinal conditions.

Objectives

We aimed to evaluate the relative (1) clinical effectiveness of two strategies (i.e. emergency surgery vs. non-emergency surgery strategies) for five common acute conditions presenting as emergency admissions; (2) cost-effectiveness for five common acute conditions presenting as emergency admissions; and (3) clinical effectiveness and cost-effectiveness of the alternative strategies for specific patient subgroups.

Methods

The records of adults admitted as emergencies with acute appendicitis, cholelithiasis, diverticular disease, abdominal wall hernia or intestinal obstruction to 175 acute hospitals in England between 1 April 2010 and 31 December 2019 were extracted from Hospital Episode Statistics and linked to mortality data from the Office for National Statistics. Eligibility was determined using International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, diagnosis codes, which were agreed by clinical panel consensus. Patients having emergency surgery were identified from Office of Population Censuses and Surveys procedure codes. The study addressed the potential for unmeasured confounding with an instrumental variable design. The instrumental variable was each hospital’s propensity to use emergency surgery compared with non-emergency surgery strategies. The primary outcome was the ‘number of days alive and out of hospital’ at 90 days. We reported the relative effectiveness of the alternative strategies overall, and for prespecified subgroups (i.e. age, number of comorbidities and frailty level). The cost-effectiveness analyses used resource use and mortality from the linked data to derive estimates of incremental costs, quality-adjusted life-years and incremental net monetary benefits at 1 year.

Results

Cohort sizes were as follows: 268,144 admissions with appendicitis, 240,977 admissions with cholelithiasis, 138,869 admissions with diverticular disease, 106,432 admissions with a hernia and 133,073 admissions with an intestinal obstruction. Overall, at 1 year, the average number of days alive and out of hospitals at 90 days, costs and quality-adjusted life-years were similar following either strategy, after adjusting for confounding. For each of the five conditions, overall, the 95% confidence intervals (CIs) around the incremental net monetary benefit estimates all included zero. For patients with severe frailty, emergency surgery led to a reduced number of days alive and out of hospital and was not cost-effective compared with non-emergency surgery, with incremental net monetary benefit estimates of –£18,727 (95% CI –£23,900 to –£13,600) for appendicitis, –£7700 (95% CI –£13,000 to –£2370) for cholelithiasis, –£9230 (95% CI –£24,300 to £5860) for diverticular disease, –£16,600 (95% CI –£21,100 to –£12,000) for hernias and –£19,300 (95% CI –£25,600 to –£13,000) for intestinal obstructions. For patients who were ‘fit’, emergency surgery was relatively cost-effective, with estimated incremental net monetary benefit estimates of £5180 (95% CI £684 to £9680) for diverticular disease, £2040 (95% CI £996 to £3090) for hernias, £7850 (95% CI £5020 to £10,700) for intestinal obstructions, £369 (95% CI –£728 to £1460) for appendicitis and £718 (95% CI £294 to £1140) for cholelithiasis. Public and patient involvement translation workshop participants emphasised that these findings should be made widely available to inform future decisions about surgery.

Limitations

The instrumental variable approach did not eliminate the risk of confounding, and the acute hospital perspective excluded costs to other providers.

Conclusions

Neither strategy was more cost-effective overall. For patients with severe frailty, non-emergency surgery strategies were relatively cost-effective. For patients who were fit, emergency surgery was more cost-effective.

Future work

For patients with multiple long-term conditions, further research is required to assess the benefits and costs of emergency surgery.

Study registration

This study is registered as reviewregistry784.

Funding

This project was funded by the National Institute for Health and Care Research (IHR) Health and Social Care Delivery Research programme and will be published in full in Health and Social Care Delivery Research; Vol. 11, No. 1. See the NIHR Journals Library website for further project information.

A Cost-Utility Analysis of the Use of Closed-Incision Negative Pressure System in Vascular Surgery Groin Incisions

OBJECTIVE

Closed-incision negative pressure therapy (CINPT) with the Prevena system has been used and clinically evaluated in high-risk groin incisions to reduce the risk of postoperative complications. We performed a cost-effectiveness analysis evaluating CINPT in femoral-popliteal bypass with prosthetic graft.

METHODS

A literature review looking at prospective randomized trials determined the probabilities and outcomes for femoral-popliteal bypass with and without CINPT. Reported utility scores were used to estimate the quality adjusted life years (QALYs) associated with a successful procedure and postoperative complications. Medicare current procedure terminology and diagnosis-related group codes were used to assess the costs for a successful surgery and associated complications. A decision analysis tree was constructed with rollback analysis to highlight the more cost-effective strategy. An incremental cost-effectiveness ratio (ICER) analysis was performed with a willingness to pay at $50,000. Deterministic and probabilistic sensitivity analyses were performed to validate the robustness of the results, and to accommodate for the uncertainty in the literature.

RESULTS

Femoral-popliteal bypass with CINPT is less costly ($40,138 vs $41,774) and more effective (6.14 vs 6.13) compared to without CINPT. This resulted in a negative ICER of -234,764.03, which favored CINPT, indicating a dominant strategy. In one-way sensitivity analysis, surgery without CINPT was more cost-effective if the probability of successful surgery falls below 84.9% or if the cost of CINPT exceeds $3139. Monte Carlo analysis showed a confidence of 99.07% that CINPT is more cost-effective.

CONCLUSIONS

Despite the added device cost of CINPT, it is cost-effective in vascular surgical operations using groin incisions.

A cost-utility analysis comparing large volume displacement oncoplastic surgery to mastectomy with free flap reconstruction in the treatment of breast cancer

PURPOSE

Breast cancer surgical treatment may include large volume displacement oncoplastic surgery (LVOS) or mastectomy with free flap reconstruction (MFFR). We investigated the cost-utility between LVOS versus MFFR to determine which approach was most cost-effective.

METHODS

A literature review was performed to calculate probabilities for clinical outcomes for each surgical option (LVOS versus MFFR), and to obtain utility scores that were converted into quality adjusted life years (QALYs) as measures for clinical effectiveness. Average Medicare payments were surrogates for cost. A decision tree was constructed and an incremental cost-utility ratio (ICUR) was used to calculate cost-effectiveness.

RESULTS

The decision tree demonstrates associated QALYs and costs with probabilities used to calculate the ICUR of $3699/QALY with gain of 2.7 QALY at an additional cost of $9987 proving that LVOS is a cost-effective surgical option. One-way sensitivity analysis showed that LVOS became cost-ineffective when its clinical effectiveness had a QALY of less than 30.187. Tornado Diagram Analysis and Monte-Carlo simulation supported our conclusion.

CONCLUSION

LVOS is cost-effective when compared to MFFR for the appropriate breast cancer patient.

CLINICAL QUESTION/LEVEL OF EVIDENCE

II.

A Current Review of Hybrid Meshes in Abdominal Wall Reconstruction

Complex abdominal wall defects remain a common problem, though there has been significant advancement in technique and biomaterials over the last decade. The newly developed hybrid meshes are targeted to address several shortcomings of other meshes. Specifically, the marriage of biosynthetic or biologic materials with permanent prosthetic material is designed so that each will counteract the other's negative attributes. There are reports of permanent meshes having been associated with chronic pain, stiffness, and inflammation. However, their utility in maintaining biomechanical strength, thus limiting recurrence, makes them of value. In hybrid meshes, biosynthetic or biologic materials are coupled with permanent prosthetics, potentially protecting them from exhibiting deleterious effects by promoting and hastening tissue ingrowth. The various hybrid meshes currently available and investigational data are reviewed.

A cost-utility analysis comparing large volume displacement oncoplastic surgery to mastectomy with single stage implant reconstruction in the treatment of breast cancer

BACKGROUND

For larger cancers in moderate to large breast sized women, breast surgical cancer treatment may include large volume displacement oncoplastic surgery (LVOS) or mastectomy with single stage implant reconstruction (SSIR). Often in the case of LVOS, reduction mammaplasty designs are used in the oncoplastic reconstructions with a contralateral symmetry operation. The goal of this study was to investigate the cost-utility between LVOS versus SSIR to determine which approach is cost-effective in the treatment of breast cancer.

METHODS

A review of the literature was performed to determine baseline values and ranges. An average national Medicare payment rates using DRG and CPT codes were used for cost assessment. After constructing a decision tree, an incremental cost-utility ratio (ICUR) was calculated comparing the difference for both surgical options in costs by the difference in clinical-effectiveness. To validate our results, we performed one-way sensitivity analyses in addition to a Monte-Carlo analysis.

RESULTS

An ICUR of $546.81/QALY favoring LVOS was calculated based off of its clinical-effectiveness gain of 7.67 QALY at an additional cost of $4194. One-way sensitivity analyses underscored the degree by which LVOS was cost-effective. For example, LVOS became cost-ineffective when a successful LVOS cost more than $50,000. Similarly, probabilistic sensitivity analysis using Monte-Carlo simulation showed that even with varying multiple variables at once, results tended to favor our conclusion supporting the cost-effectiveness of LVOS.

CONCLUSIONS

For the appropriate patients with moderate to large sized breasts with breast cancer, large volume displacement oncoplastic surgery is cost-effective compared to mastectomy with single staged implant reconstruction.

Robotic Versus Open Renal Transplantation in Obese Patients: Protocol for a Cost-Benefit Markov Model Analysis

Background

Recent studies have reported a significant decrease in wound problems and hospital stay in obese patients undergoing renal transplantation by robotic-assisted minimally invasive techniques with no difference in graft function.

Objective

Due to the lack of cost-benefit studies on the use of robotic-assisted renal transplantation versus open surgical procedure, the primary aim of our study is to develop a Markov model to analyze the cost-benefit of robotic surgery versus open traditional surgery in obese patients in need of a renal transplant.

Methods

Electronic searches will be conducted to identify studies comparing open renal transplantation versus robotic-assisted renal transplantation. Costs associated with the two surgical techniques will incorporate the expenses of the resources used for the operations. A decision analysis model will be developed to simulate a randomized controlled trial comparing three interventional arms: (1) continuation of renal replacement therapy for patients who are considered non-suitable candidates for renal transplantation due to obesity, (2) transplant recipients undergoing open transplant surgery, and (3) transplant patients undergoing robotic-assisted renal transplantation. TreeAge Pro 2017 R1 TreeAge Software, Williamstown, MA, USA) will be used to create a Markov model and microsimulation will be used to compare costs and benefits for the two competing surgical interventions.

Results

The model will simulate a randomized controlled trial of adult obese patients affected by end-stage renal disease undergoing renal transplantation. The absorbing state of the model will be patients' death from any cause. By choosing death as the absorbing state, we will be able simulate the population of renal transplant recipients from the day of their randomization to transplant surgery or continuation on renal replacement therapy to their death and perform sensitivity analysis around patients' age at the time of randomization to determine if age is a critical variable for cost-benefit analysis or cost-effectiveness analysis comparing renal replacement therapy, robotic-assisted surgery or open renal transplant surgery. After running the model, one of the three competing strategies will result as the most cost-beneficial or cost-effective under common circumstances. To assess the robustness of the results of the model, a multivariable probabilistic sensitivity analysis will be performed by modifying the mean values and confidence intervals of key parameters with the main intent of assessing if the winning strategy is sensitive to rigorous and plausible variations of those values.

Conclusions

After running the model, one of the three competing strategies will result as the most cost-beneficial or cost-effective under common circumstances. To assess the robustness of the results of the model, a multivariable probabilistic sensitivity analysis will be performed by modifying the mean values and confidence intervals of key parameters with the main intent of assessing if the winning strategy is sensitive to rigorous and plausible variations of those values.

Initial Experience With Biologic Polymer Scaffold (Poly-4-hydroxybuturate) in Complex Abdominal Wall Reconstruction

OBJECTIVE

To evaluate the use of the new absorbable polymer scaffold poly-4-hydroxybutyrate (P4HB) in complex abdominal wall reconstruction.

BACKGROUND

Complex abdominal wall reconstruction has witnessed tremendous success in the last decade after the introduction of cadaveric biologic scaffolds. However, the use of cadaveric biologic mesh has been expensive and plagued by complications such as seroma, infection, and recurrent hernia. Despite widespread application of cadaveric biologic mesh, little data exist on the superiority of these materials in the setting of high-risk wounds in patients. P4HB, an absorbable polymer scaffold, may present a new alternative to these cadaveric biologic grafts.

METHODS

A retrospective analysis of our initial experience with the absorbable polymer scaffold P4HB compared with a consecutive contiguous group treated with porcine cadaveric mesh for complex abdominal wall reconstructions. Our analysis was performed using SAS 9.3 and Stata 12.

RESULTS

The P4HB group (n = 31) experienced shorter drain time (10.0 vs 14.3 d; P < 0.002), fewer complications (22.6% vs 40.5%; P < 0.046), and reherniation (6.5% vs 23.8%; P < 0.049) than the porcine cadaveric mesh group (n = 42). Multivariate analysis for infection identified: porcine cadaveric mesh odds ratio 2.82, length of stay odds ratio 1.11; complications: drinker odds ratio 6.52, porcine cadaveric mesh odds ratio 4.03, African American odds ratio 3.08, length of stay odds ratio 1.11; and hernia recurrence: porcine cadaveric mesh odds ratio 5.18, drinker odds ratio 3.62, African American odds ratio 0.24. Cost analysis identified that P4HB had a $7328.91 financial advantage in initial hospitalization and $2241.17 in the 90-day postdischarge global period resulting in $9570.07 per case advantage over porcine cadaveric mesh.

CONCLUSIONS

In our early clinical experience with the absorbable polymer matrix scaffold P4HB, it seemed to provide superior clinical performance and value-based benefit compared with porcine cadaveric biologic mesh.

A Cost-Utility Assessment of Mesh Selection in Clean-Contaminated Ventral Hernia Repair

BACKGROUND

Mesh reinforcement can reduce hernia recurrence, but mesh selection is poorly understood, particularly in contaminated defects. Acellular dermal matrix has enabled single-stage ventral hernia repair in clean-contaminated wounds but can be associated with higher complications and cost compared with synthetic mesh. This study evaluated the cost-utility of synthetic mesh and acellular dermal matrix for clean-contaminated ventral hernia repairs.

METHODS

A systematic review of articles comparing outcomes for synthetic and acellular dermal matrix repairs identified 14 ventral hernia repair-specific health states. Quality-adjusted life years were determined through Web-based visual analog scale survey of 300 nationally representative individuals. Overall expected cost and quality-adjusted life-years for ventral hernia repair were assessed using a Monte Carlo simulation with sensitivity analyses.

RESULTS

Synthetic mesh reinforcement had an expected cost of $15,776 and quality-adjusted life-year value gained of 21.03. Biological mesh had an expected cost of $23,844 and quality-adjusted life-year value gained of 20.94. When referencing a common baseline (do nothing), acellular dermal matrix (incremental cost-effectiveness ratio, 3378 ($/quality-adjusted life years)) and synthetic mesh (incremental cost-effectiveness ratio, 2208 ($/quality-adjusted life years)) were judged cost-effective, although synthetic mesh was more strongly favored. Monte Carlo sensitivity analysis demonstrated that synthetic mesh was the preferred and most cost-effective strategy in 94 percent of simulations, supporting its overall greater cost-utility. Despite varying the willingness-to-pay threshold from $0 to $100,000 per quality-adjusted life-year, synthetic mesh remained the optimal strategy across all thresholds in sensitivity analysis.

CONCLUSION

This cost-utility analysis suggests that synthetic mesh repair of clean-contaminated hernia defects is more cost-effective than acellular dermal matrix.

Cost-Utility Analysis: Sartorius Flap versus Negative Pressure Therapy for Infected Vascular Groin Graft Managment

Background:

Sartorius flap coverage and adjunctive negative pressure wound therapy (NPWT) have been described in managing infected vascular groin grafts with varying cost and clinical success. We performed a cost–utility analysis comparing sartorius flap with NPWT in managing an infected vascular groin graft.

Methods:

A literature review compiling outcomes for sartorius flap and NPWT interventions was conducted from peer-reviewed journals in MEDLINE (PubMed) and EMBASE. Utility scores were derived from expert opinion and used to estimate quality-adjusted life years (QALYs). Medicare current procedure terminology and diagnosis-related groups codes were used to assess the costs for successful graft salvage with the associated complications. Incremental cost-effectiveness was assessed at $50,000/QALY, and both univariate and probabilistic sensitivity analyses were conducted to assess robustness of the conclusions.

Results:

Thirty-two studies were used pooling 384 patients (234 sartorius flaps and 150 NPWT). NPWT had better clinical outcomes (86.7% success rate, 0.9% minor complication rate, and 13.3% major complication rate) than sartorius flap (81.6% success rate, 8.0% minor complication rate, and 18.4% major complication rate). NPWT was less costly ($12,366 versus $23,516) and slightly more effective (12.06 QALY versus 12.05 QALY) compared with sartorius flap. Sensitivity analyses confirmed the robustness of the base case findings; NPWT was either cost-effective at $50,000/QALY or dominated sartorius flap in 81.6% of all probabilistic sensitivity analyses.

Conclusion:

In our cost–utility analysis, use of adjunctive NPWT, along with debridement and antibiotic treatment, for managing infected vascular groin graft wounds was found to be a more cost-effective option when compared with sartorius flaps.