The volume-outcome relationship in free-flap reconstruction: A nationwide study based on the Clinical Database

BACKGROUND

The association between successful reconstructive surgery with a free flap and hospital volume has not been well established. This study was designed to retrospectively analyze the outcome of free-flap surgery registered in a nationwide surgical registration system in Japan to clarify the relationship between free-flap survival and facilities' average annual number of free-flap surgeries.

METHODS

We analyzed data from 19,482 free flaps performed during 2017-2020 at 407 facilities throughout Japan. After adjusting for sex, age, and disease classification that differ between the groups, we examined the differences in the flap survival rates among the different facilities in terms of the average number of free-flap surgeries performed annually.

RESULTS

The total overall necrosis rate was 2.8%. Of all procedures, 14.9%, 12.9%, 33.4%, and 38.8% were performed at facilities with an average number of free-flap procedures <10, 10-19, 20-49, and ≥ 50 per year, respectively, and the respective rates of total necrosis were 6.0%, 3.8%, 2.1%, and 1.7%, respectively. The odds ratios and 95% confidence intervals of flap necrosis for facilities with ≥ 50 cases per year relative to those <10 were 2.70 (1.98-3.68) for nonbreast reconstruction cases and 5.72 (2.77-11.8) for breast reconstruction cases.

CONCLUSION

This analysis of a nationwide plastic surgery database showed that free-flap surgeries in institutions with a low average annual number of free-flap surgeries had a higher risk of total necrosis. Measures should be taken to either aggregate cases into high-volume centers or improve management at low-volume centers.

Identifying ways to improve diabetes management during cancer treatments (INDICATE): protocol for a qualitative interview study with patients and clinicians

INTRODUCTION

A large and growing number of patients with cancer have comorbid diabetes. Cancer and its treatment can adversely impact glycaemic management and control, and there is accumulating evidence that suboptimal glycaemic control during cancer treatment is a contributory driver of worse cancer-related outcomes in patients with comorbid diabetes. Little research has sought to understand, from the perspective of patients and clinicians, how and why different aspects of cancer care and diabetes care can complicate or facilitate each other, which is key to informing interventions to improve diabetes management during cancer treatments. This study aims to identify and elucidate barriers and enablers to effective diabetes management and control during cancer treatments, and potential intervention targets and strategies to address and harness these, respectively.

METHODS AND ANALYSIS

Qualitative interviews will be conducted with people with diabetes and comorbid cancer (n=30-40) and a range of clinicians (n=30-40) involved in caring for this patient group (eg, oncologists, diabetologists, specialist nurses, general practitioners). Semistructured interviews will examine participants' experiences of and perspectives on diabetes management and control during cancer treatments. Data will be analysed using framework analysis. Data collection and analysis will be informed by the Theoretical Domains Framework, and related Theory and Techniques Tool and Behaviour Change Wheel, to facilitate examination of a comprehensive range of barriers and enablers and support identification of pertinent and feasible intervention approaches. Study dates: January 2021-January 2023.

ETHICS AND DISSEMINATION

The study has approval from National Health Service (NHS) West Midlands-Edgbaston Research Ethics Committee. Findings will be presented to lay, clinical, academic and NHS and charity service-provider audiences via dissemination of written summaries and presentations, and published in peer-reviewed journals. Findings will be used to inform development and implementation of clinical, health services and patient-management intervention strategies to optimise diabetes management and control during cancer treatments.

Head and neck cancer associated with myiasis

Head and neck cancer patients represent a risk group for the development of fly larvae infestation in neoplastic wounds. This condition can accelerate the disease progression and increase its lethality due to local or systemic complications. The aim of this study was to conduct a scoping review on head and neck cancer associated with myiasis in order to answer the focal question: what are the occurrence, diagnosis, aetiology, treatment and outcomes of head and neck cancer associated with myiasis? This paper was structured based on the five-steps methodology proposed by Arksey and O'Malley (Int J Soc Res Methodol 2005;1:19-32), and followed the PRISMA Extension for Scoping Reviews (PRISMA-ScR), OSF Registries protocol. The electronic search was performed in the MEDLINE/PubMed, Embase and SciELO.org databases for articles published up to 28 February 2021. In total, 38 articles and 56 patients were included. Most patients were male (66%), and the mean age was 66.63 years. Cases were predominantly associated with squamous or basal cell cancer. The most affected anatomical sites were the eyes, scalp, ears and oral cavity, and the most frequent type of larva was Crisomyia (13%). Manual removal of the larvae was considered the standard treatment, associated or not with antibiotics, analgesics and antiparasitic drugs.

Impact of Diabetes Mellitus on Adverse Outcomes After Meningioma Surgery

OBJECTIVE

We sought to investigate the association between diabetes mellitus and incidence of adverse outcomes in patients who underwent meningioma surgery.

METHODS

The 2012-2014 National Inpatient Sample database was used. Prolonged length of stay was indicated by values greater than the 90th percentile of the sample. The Fisher exact test and analysis of variance were used to compare demographics, hospital characteristics, comorbidity, and complications among race cohorts. Logistic regression was used to analyze the independent effect of diabetes on adverse outcomes.

RESULTS

After selecting for patients with primary diagnosis of meningioma who underwent a resection procedure, 7745 individuals were identified and divided into diabetic (n = 1518) and nondiabetic (n = 6227) cohorts. Demographics, hospital characteristics, and comorbidities were significantly different among the 2 cohorts. Average length of stay was longer in diabetic patients (8.15 vs. 6.04 days, P < 0.001), and total charges were higher in diabetic patients ($139,462.66 vs. $123,250.71, P < 0.001). Multivariate regression indicated diabetic patients have higher odds of experiencing a complication (odds ratio [OR] 1.442, 95% confidence interval [CI] 1.255-1.656, P < 0.001) and in-hospital mortality (OR 1.672, 95% CI 1.034-2.705, P = 0.036) after meningioma surgery. Analysis of individual postoperative complications revealed that diabetic patients experienced increased odds of pulmonary (OR 1.501, 95% CI 1.209-1.864, P < 0.001), neurologic (OR 1.690, 95% CI 1.383-2.065, P < 0.001), and urinary/renal complications (OR 2.618, 95% CI 1.933-3.545, P < 0.001). In addition, diabetic patients were more likely to have a prolonged length of stay (OR 1.694, 95% CI 1.389-2.065, P < 0.001).

CONCLUSIONS

Diabetes is an important factor associated with complications after meningioma surgery. Preventative measures must be taken to optimize postoperative outcomes in these patients.

Clinical consequences of head and neck free-flap reconstructions in the DM population

Diabetes mellitus (DM) is a common comorbidity and risk factor for postoperative complications in head and neck (H&N) microsurgical reconstructions. Our study focused on the association between DM and individual complications regarding both surgical and medical aspects. A meta-analysis of English-language articles comparing a series of complications between DM and non-DM H&N free-flap recipients was performed by comprehensive meta-analysis (CMA). Twenty-seven articles presented 14,233 H&N free-flap reconstructions, and a subset of 2329 analyses including diabetic cases was included for final analysis. Total postoperative (RR = 1.194, p < 0.001; OR = 1.506, p = 0.030) and surgical (RR = 1.550, p = 0.001; OR = 3.362, p < 0.001) complications were increased in DM subjects. Free-flap failure/necrosis (RR = 1.577, p = 0.001; OR = 1.999, p = 0.001) and surgical site infections (OR = 2.414, p < 0.001) were also increased in diabetic recipients. However, return to the operating room, dehiscence, fistulas, plate exposures, readmissions, and mortalities were not increased in DM patients. DM increased various complications in H&N free-flap reconstructions. Surgical indications should be cautiously evaluated, and aggressive treatments should be implemented for high-risk recipients.

The secretome of stressed peripheral blood mononuclear cells increases tissue survival in a rodent epigastric flap model

Reconstructive surgery transfers viable tissue to cover defects and to restore aesthetic and functional properties. Failure rates after free flap surgery range from 3 to 7%. Co-morbidities such as diabetes mellitus or peripheral vascular disease increase the risk of flap failure up to 4.5-fold. Experimental therapeutic concepts commonly use a monocausal approach by applying single growth factors. The secretome of γ-irradiated, stressed peripheral blood mononuclear cells (PBMCsec) resembles the physiological environment necessary for tissue regeneration. Its application led to improved wound healing rates and a two-fold increase in blood vessel counts in previous animal models. We hypothesized that PBMCsec has beneficial effects on the survival of compromised flap tissue by reducing the necrosis rate and increasing angiogenesis. Surgery was performed on 39 male Sprague-Dawley rats (control, N = 13; fibrin sealant, N = 14; PBMCsec, N = 12). PBMCsec was produced according to good manufacturing practices (GMP) guidelines and 2 ml were administered intraoperatively at a concentration of 2.5 × 107 cells/ml using fibrin sealant as carrier substance. Flap perfusion and necrosis (as percentage of the total flap area) were analyzed using Laser Doppler Imaging and digital image planimetry on postoperative days 3 and 7. Immunohistochemical stainings for von Willebrand factor (vWF) and Vascular Endothelial Growth Factor-receptor-3 (Flt-4) were performed on postoperative day 7 to evaluate formation of blood vessels and lymphatic vessels. Seroma formation was quantified using a syringe and flap adhesion and tissue edema were evaluated clinically through a cranial incision by a blinded observer according to previously described criteria on postoperative day 7. We found a significantly reduced tissue necrosis rate (control: 27.8% ± 8.6; fibrin: 22.0% ± 6.2; 20.9% reduction, p = .053 vs. control; PBMCsec: 19.1% ± 7.2; 31.1% reduction, p = .012 vs. control; 12.9% reduction, 0.293 vs. fibrin) together with increased vWF+ vessel counts (control: 70.3 ± 16.3 vessels/4 fields at 200× magnification; fibrin: 67.8 ± 12.1; 3.6% reduction, p = .651, vs. control; PBMCsec: 85.9 ± 20.4; 22.2% increase, p = .045 vs. control; 26.7% increase, p = .010 vs. fibrin) on postoperative day 7 after treatment with PBMCsec. Seroma formation was decreased after treatment with fibrin sealant with or without the addition of PBMCsec. (control: 11.9 ± 9.7 ml; fibrin: 1.7 ± 5.3, 86.0% reduction, 0.004 vs. control; PBMCsec: 0.6 ± 2.0; 94.8% reduction, p = .001 vs. control; 62.8% reduction, p = .523 vs. fibrin). We describe the beneficial effects of a secretome derived from γ-irradiated PBMCs on tissue survival, angiogenesis, and clinical parameters after flap surgery in a rodent epigastric flap model.