External validation and revision of Penn incisional hernia prediction model: A large-scale retrospective cohort of abdominal operations.

BACKGROUND: Incisional hernia (IH) manifests in 10%-15% of abdominal surgeries and patients at elevated risk of this complication should be identified for prophylactic intervention. This study aimed to externally validate the Penn hernia risk calculator. METHODS: The Ramathibodi abdominal surgery cohort was constructed by linking relevant hospital databases from 2010 to 2021. Penn hernia risk scores were calculated according to the original model which was externally validated using a seven-step approach. An updated model which included four additional predictor variables (i.e., age, immunosuppressive medication, ostomy reversal, and transfusion) added to those of the three original predictors (i.e., body mass index, chronic liver disease, and open surgery) was also evaluated. The area under the receiver operating characteristic curve (AUC) was estimated, and calibration performance was compared using the Hosmer-Lemeshow goodness-of-fit method for the observed/expected (O/E) ratio. RESULTS: A total of 12,155 abdominal operations were assessed. The original Penn model yielded fair discrimination with an AUC (95% confidence interval (CI)) of 0.645 (0.607, 0.683). The updated model that included the additional predictor variables achieved an acceptable AUC (95% CI) of 0.733 (0.698, 0.768) with the O/E ratio of 0.968 (0.848, 1.088). CONCLUSION: The updated model achieved improved discrimination and calibration performance, and should be considered for the identification of high-risk patients for further hernia prevention strategy.

Delayed versus primary closure to minimize risk of surgical-site infection for complicated appendicitis: A secondary analysis of a randomized trial using counterfactual prediction modeling.

OBJECTIVE: To evaluate the risk of surgical site infection (SSI) following complicated appendectomy in individual patients receiving delayed primary closure (DPC) versus primary closure (PC) after adjustment for individual risk factors. DESIGN: Secondary analysis of randomized controlled trial (RCT) with prediction model. SETTING: Referral centers across Thailand. PARTICIPANTS: Adult patients who underwent appendectomy via a lower-right-quadrant abdominal incision due to complicated appendicitis. METHODS: A secondary analysis of a published RCT was performed applying a counterfactual prediction model considering interventions (PC vs DPC) and other significant predictors. A multivariable logistic regression was applied, and a likelihood-ratio test was used to select significant predictors to retain in a final model. Factual versus counterfactual SSI risks for individual patients along with individual treatment effect (iTE) were estimated. RESULTS: In total, 546 patients (271 PC vs 275 DPC) were included in the analysis. The individualized prediction model consisted of allocated intervention, diabetes, type of complicated appendicitis, fecal contamination, and incision length. The iTE varied between 0.4% and 7% for PC compared to DPC; ∼38.1% of patients would have ≥2.1% lower SSI risk following PC compared to DPC. The greatest risk reduction was identified in diabetes with ruptured appendicitis, fecal contamination, and incision length of 10 cm, where SSI risks were 47.1% and 54.1% for PC and DPC, respectively. CONCLUSIONS: In this secondary analysis, we found that most patients benefited from early PC versus DPC. Findings may be used to inform SSI prevention strategies for patients with complicated appendicitis.

Accuracy and external validation of the modified rapid emergency medicine score in road traffic injuries in a Bangkok level I trauma center.

Background: Trauma is a significant public health problem. Therefore, many injury scores have been created to predict mortality and triage patients. This study aims to validate the modified Rapid Emergency Medicine Score (mREMS) for in-hospital mortality prediction in road traffic injuries and compare the mREMS with the revised trauma score (RTS) and the mechanisms, Glasgow Coma Scale (GCS), age, and arterial pressure (MGAP) score. Methods: Data were retrospectively collected from the Vajira Hospital (1,033 cases). The mREMS was calculated from six predictors: age, systolic blood pressure, heart rate, respiratory rate, pulse oxygen saturation, and GCS. The receiver operating characteristic curve was plotted, and the area under the curve (AUC) was calculated. The AUC and 95% confidence interval (CI) of the mREMS were compared with the AUCs of other scores. Model calibration was assessed using the Hosmer-Lemeshow goodness-of-fit test. Results: The mREMS was significantly better than the RTS at predicting death in road traffic injury patients [mREMS: AUCs, 0.909 (95% CI, 0.866-0.951); RTS: AUCs, 0.859 (95% CI, 0.791-0.927] (p = 0.023). However, the difference between the AUCs of the mREMS and MGAP score was not statistically significant (p = 0.150). The mREMS' calibration performance was also satisfactory in this dataset based on the Hosmer-Lemeshow goodness-of-fit test (p = 0.277). Conclusion: In the road traffic injury population, the mREMS is an excellent predictor of in-hospital mortality. These results can be applied to improve triage. However, this score should be further validated in other trauma centers before nationwide implementation.

Fascial Dehiscence and Incisional Hernia Prediction Models: A Systematic Review and Meta-analysis.

BACKGROUND: Fascial dehiscence (FD) and incisional hernia (IH) pose considerable risks to patients who undergo abdominal surgery, and many preventive strategies have been applied to reduce this risk. An accurate predictive model could aid identification of high-risk patients, who could be targeted for particular care. This study aims to systematically review existing FD and IH prediction models. METHODS: Prediction models were identified using pre-specified search terms on SCOPUS, PubMed, and Web of Science. Eligible studies included those conducted in adult patients who underwent any kind of abdominal surgery, and reported model performance. Data from the eligible studies were extracted, and the risk of bias (RoB) was assessed using the PROBAST tool. Pooling of C-statistics was performed using a random-effect meta-analysis. [Registration: PROSPERO (CRD42021282463)]. RESULTS: Twelve studies were eligible for review; five were FD prediction model studies. Most included studies had high RoB, especially in the analysis domain. The C-statistics of the FD and IH prediction models ranged from 0.69 to 0.92, but most have yet to be externally validated. Pooled C-statistics (95% CI) were 0.80 (0.74, 0.86) and 0.81 (0.75, 0.86) for the FD (external-validation) and IH prediction model, respectively. Some predictive factors such as body mass index, smoking, emergency operation, and surgical site infection were associated with FD or IH occurrence and were included in multiple models. CONCLUSIONS: Several models have been developed as an aid for FD and IH prediction, mostly with modest performance and lacking independent validation. New models for specific patient groups may offer clinical utility.

Cost-effectiveness analysis of mesh fixation techniques for laparoscopic and open inguinal hernia surgeries.

PURPOSE: This study reports economic evaluation of mesh fixation in open and laparoscopic hernia repair from a prospective real-world cohort study, using cost-effectiveness analysis (CEA) and cost-utility analysis (CUA). METHODS: A prospective real-world cohort study was conducted in two university-based hospitals in Thailand from November 2018 to 2019. Patient data on hernia features, operative approaches, clinical outcomes, associated cost data, and quality of life were collected. Models were used to determine each group's treatment effect, potential outcome means, and average treatment effects. An incremental cost-effectiveness ratio was used to evaluate the incremental risk of hernia recurrences. RESULTS: The 261 patients in this study were divided into six groups: laparoscopic with tack (LT, n = 47), glue (LG, n = 26), and self-gripping mesh (LSG, n = 30), and open with suture (OS, n = 117), glue (OG, n = 18), and self-gripping mesh (OSG, n = 23). Hernia recurrence was most common in LSG. The mean utility score was highest in OG and OSG (both 0.99). Treatment costs were generally higher for laparoscopic than open procedures. The cost-effectiveness plane for utility and hernia recurrence identified LSG as least cost effective. Cost-effectiveness acceptability curves identified OG as having the highest probability of being cost effective at willingness to pay levels between $0 and $3,300, followed by OSG. CONCLUSION: Given the similarity of hernia recurrence among all major procedures, the cost of surgery may impact the decision. According to our findings, open hernia repair with adhesive or self-gripping mesh appears most cost-effective.

Mesh-fixation technique for inguinal hernia repair: umbrella review.

BACKGROUND: Mesh-based repair is the standard of surgical care for symptomatic inguinal hernias. Many systematic reviews and meta-analyses (SRMAs) addressed various aspects of these procedures. This umbrella review aimed to report the evidence from all previous SRMAs for open and laparoscopic inguinal hernia repair. METHODS: SRMAs were identified from MEDLINE, Scopus, Cochrane, Embase, DARE, PROSPERO, CINAHL, JBISRIS, EPPI-Centre, Wiley Online Library and ScienceDirect database according to PRISMA guidelines. Data including mesh-fixation techniques and surgical approach were extracted from selected SRMAs. The corrected covered area was calculated to address study overlap across reviews, and an excess significance test was used to assess potential bias. The outcomes of interest were hernia recurrence, chronic groin pain, operating time, postoperative pain, duration of hospital stay, return to daily life activities, and postoperative complication. RESULTS: Thirty SRMAs were included between 2010 and 2019: 16 focused on open repair, and 14 focused on laparoscopic repair, with a high degree of overlap (open repairs, 41 per cent; laparoscopic repairs, 30-57 per cent). Sufficient evidence was available on hernia recurrence, chronic groin pain, and operative time. Effects of glue on hernia recurrence were inconclusive in open and laparoscopy approaches, P = 0.816 and 0.946 respectively. Glue was significantly associated with lower persistent groin pain, in open repair (versus suture) and in laparoscopic repair (versus tack). SRMAs suggested that self-gripping mesh was associated with shorter operating time in open surgery, although with only a few minutes of improvement (0.36-7.85 min, P < 0.001). CONCLUSION: In this umbrella review, chronic groin pain and operating time were the only outcomes for which there was sufficient evidence supporting the effectiveness respectively of glue and self-gripping mesh.

The Myopectineal Orifice: A Study of Thai Cadavers.

Objective: This study aimed to determine the myopectineal orifice size measured in Thai human cadavers. Materials and Methods: A total of 30 human cadavers, comprising 55 groins, were assessed. Myopectineal orifices (MPOs) were measured in two dimensions: height from the lower border of the conjoined tendon to the upper border of the pectineal ligament and width from the lateral border of pubic tubercle to the medial border of the iliopsoas muscle. Results: The mean MPO size is 7.13 + 0.14 cm in width and 6.66 + 0.32 m in height. The mean width and height in male cadavers are 7.16 + 0.14 and 6.84 + 0.27 cm, respectively. The mean width and height in female cadavers are 7.09 + 0.12 and 6.45 + 0.24 cm, respectively. The mean MPO area is 37.26 ± 0.027 cm2, compared with the area of mesh graft 10 cm × 15 cm, 150 cm2. Although the shrinkage of cadaveric tissue and mesh size were adjusted, which were 39.56 ± 0.029 and 81 cm2, respectively, they were found to be sufficient for the mean MPO area. It was found that the mesh size was sufficient for the mean MPO area. Conclusion: A mesh size of 10 cm × 15 cm is found to be the appropriate size to cover the MPO among Thais.

Vacuum Therapy and Internal Drainage as the First-Line Endoscopic Treatment for Post-Bariatric Leaks: A Systematic Review and Meta-Analysis.

Introduction: Several endoscopic methods can be employed to manage post-bariatric leaks. However, endoluminal vacuum therapy (EVT) and endoscopic internal drainage (EID) are relatively new methods, and studies regarding these methods are scarce. We performed a systematic review of the literature and a meta-analysis to evaluate the efficacy of EVT and EID. Methods: Databases were searched for eligible studies. The clinical success of leak closure was the primary outcome of interest. A proportional meta-analysis was performed for pooling the primary outcome using a fixed-effects model. A meta-analysis or descriptive analysis of other outcomes was performed based on the data availability. Results: Data from 3 EVT and 10 EID studies (n = 279) were used for evidence synthesis. The leak closure rates (95% confidence interval [CI]) of EVT and EID were 85.2% (75.1%-95.4%) and 91.6% (88.1%-95.2%), respectively. The corresponding mean treatment durations (95% CI) were 28 (2.4-53.6) and 78.4 (50.1-106.7) days, respectively. However, data about other outcomes were extremely limited; thus, a pooled analysis could not be performed. Conclusions: Both EVT and EID were effective when used as the first-line treatment for post-bariatric leaks. However, larger studies must be conducted to compare the efficacy of the 2 interventions.

Prediction of seroma after total mastectomy using an artificial neural network algorithm.

Seroma is a common complication after mastectomy. To the best of our knowledge, no prediction models have been developed for this. Henceforth, medical records of total mastectomy patients were retrospectively reviewed. Data consisting of 120 subjects were divided into a training-validation data set (96 subjects) and a testing data set (24 subjects). Data was learned by using a 9-layer artificial neural network (ANN), and the model was validated using 10-fold cross-validation. The model performance was assessed by a confusion matrix in the validating data set. The receiver operating characteristic curve was constructed, and the area under the curve (AUC) was also calculated. Pathology type, presence of hypertension, presence of diabetes, receiving of neoadjuvant chemotherapy, body mass index, and axillary lymph node (LN) management (i.e., sentinel LN biopsy and axillary LN dissection) were selected as predictive factors in a model developed from the neural network algorithm. The model yielded an AUC of 0.760, which corresponded with a level of acceptable discrimination. Sensitivity, specificity, accuracy, and positive and negative predictive values were 100%, 52.9%, 66.7%, 46.7%, and 100%, respectively. Our model, which was developed from the ANN algorithm can predict seroma after total mastectomy with high sensitivity. Nevertheless, external validation is still needed to confirm the performance of this model.

Midline incisional hernia prophylaxis using synthetic mesh in an emergency or urgent gastrointestinal tract surgery: a protocol for multicentre randomised clinical trial.

INTRODUCTION: Between 5% and 30% of abdominal incisions eventually result in incisional hernias (IHs) that can lead to severe complications and impaired quality of life. Unfortunately, IH repair is often unsuccessful; therefore, hernia prophylaxis is an important issue. The efficacy of mesh augmentation has been proven for hernia prophylaxis in high-risk patients, but no randomised clinical trial has evaluated prophylactic mesh placement in emergency/urgent gastrointestinal operations. METHODS AND ANALYSIS: A multicentre, prospective randomised, open and patient-assessor blinded endpoint design will be conducted. A total of 470 patients will be enrolled and randomly allocated to retrorectus mesh augmentation with lightweight polypropylene mesh or primary suture closure. The primary outcome is IH occurrence within 24 months of follow-up, while other clinical outcomes are secondary endpoints. A cost-effectiveness analysis will be conducted from the societal and provider perspectives. ETHICS AND DISSEMINATION: Ethics approval was obtained from Ramathibodi Hospital (MURA2020/1478) and Vajira Hospital (COA164/2563). The protocol is on the process of submission to the local ethics committee of the other study sites. Results will be submitted for publication in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: TCTR20200924002.

Risk-benefit assessment of onlay and retrorectus mesh augmentation for incisional hernia prophylaxis: A secondary analysis from network meta-analysis.

BACKGROUND: Mesh augmentation has proved efficacious for the prevention of incisional hernia (IH). A recent network meta-analysis (NMA) identified onlay and retrorectus mesh (OM and RM) as the most effective therapeutic options, but the risk of surgical site infection (SSI) and other complications require additional consideration. METHODS: The NMA generated pooled risk differences (RD) for the benefits of reducing IH and the risk of SSI and composite seroma/hematoma (CSH) for use in Monte-Carlo data simulations with 1000 replications. Mean incremental risk-benefit ratios (IRBR), i.e., the ratio of incremental risk (or RD) and incremental benefit, and 95% confidence intervals (95% CI) were estimated with a probability of risk-benefits (PRB) across risk-benefit acceptability thresholds from the acceptability curves generated. RESULTS: The RDs of IH were 0.237 and 0.201 lower in OM and RM than primary suture closure, compared to 0.027 and -0.001 for SSI. IRBRs (95% CI) for SSI risk were -0.118 (-0.124, -0.112) and 0.006 (-0.002, 0.013) for OM and RM, respectively. PRBs were much higher in RM than OM, especially at low acceptability thresholds of 0.05 and 0.1. IRBRs (95% CI) for CSH were -0.388 (-0.395, -0.381) and -0.105 (-0.111, -0.100) for OM and RM, respectively. RM yielded a PRB of 0.87 at an acceptability threshold of 0.2, in contrast to OM, which did not. CONCLUSION: Overall, RM offered improved benefit in IH prophylaxis over the risk of complications relative to OM and appeared to be the preferred treatment option for this indication.

Mesh position for hernia prophylaxis after midline laparotomy: A systematic review and network meta-analysis of randomized clinical trials.

BACKGROUND: Mesh can be used to prevent incisional hernia (IH) occurrence. However, the effect of various mesh positions has never been compared. This study aimed to compare and rank the effect and safety of various mesh-augmented fascia closure techniques on hernia prophylaxis in midline laparotomy. METHODS: MEDLINE and SCOPUS were searched from inception to December 2019. Randomized clinical trials (RCTs) were eligible if they met the following criteria: comparison of any of the following interventions: onlay (OM), retrorectus (RM), preperitoneal (PM), intraperitoneal mesh (IM) augmentation, and primary suture closure (PSC); and reporting on any of these outcomes: IH, wound infection, seroma, hematoma, and dehiscence. Two independent reviewers extracted data and assessed the risk of bias. A two-stage random-effect network meta-analysis was performed, then intervention effects were pooled and ranked accordingly. RESULTS: A total of 20 RCTs were eligible. Only OM and RM showed a significantly lower risk of IH than PSC with pooled risk ratios (RRs), 95% confidence intervals (95%CI) of 0.24 (0.12, 0.46) and 0.32 (0.16, 0.66), and number needed to treat (NNTs) of 4 and 5, respectively. However, OM showed a significantly higher risk of seroma than PSC (RR 2.21 (1.44, 3.39) with a number needed to harm (NNH) of 14). Most mesh placements showed a higher risk of wound infection, except for RM, but none of these was significantly different. All mesh techniques, except RM, showed a reduction in dehiscence, but again these were not significantly different. CONCLUSIONS: OM and RM provided the most effective IH prevention relative to PSC. However, OM had a higher rate of seroma than RM and PSC. Other complications, including wound infection, hematoma, and dehiscence, were not significantly observed among these fascia closure techniques.

Mesh fixation technique for inguinal hernia repair: protocol for an umbrella review with integrated and updated network meta-analysis.

INTRODUCTION: Inguinal hernia mesh repair is the standard care for symptomatic inguinal hernia. Mesh fixation is used to keep mesh in place for which various mesh fixation techniques have been used in open and laparoscopic inguinal hernia repair, but their effectiveness has remained inconclusive. Therefore, we developed a protocol for an umbrella review in order to summarise the evidences with integrate and update data of different mesh fixation techniques in both open and laparoscopic inguinal hernia repair. METHODS AND ANALYSIS: Previous systematic reviews and meta-analyses will be identified from Medline, Scopus, Cochrane Databases, EMBASE, Database of Abstracts of Reviews of Effects, PROSPERO Register, CINAHL, JBISRIS, EPPI-Centre, Wiley Online Library and Science Direct database. Two reviewers will independently determine studies for eligibility. Disagreement will be solved by consensus and arbitrated by the third reviewer. Data extraction will also be performed by two independent reviewers. For umbrella review, a descriptive analysis will be applied to describe evidence of mesh fixation effectiveness. Overlapping studies and excess significance test will be performed to assess whether previous evidences are bias. In addition, individual studies from meta-analysis and additional published studies will be pooled using network meta-analyses. We will use I2 statistic and Cochran's Q test to assess heterogeneity. Risk of bias and publication bias, if appropriate, will be evaluated, as well as overall strength of the evidence. ETHICS AND DISSEMINATION: This protocol has been registered with PROSPERO and approved with Institutional Review Board, Faculty of Medicine Vajira Hospital, Navamindradhiraj University, Bangkok, Thailand (COA 167/2018). The results will be published in peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42018111773.

Mesh fixation technique in totally extraperitoneal inguinal hernia repair - A network meta-analysis.

Laparoscopic totally extra-peritoneal inguinal hernia repair is the standard option for inguinal hernia treatment. However, there are various types of mesh fixation and their relative uses are still controversial. This network meta-analysis was conducted to compare and rank the different fixations available for TEP. Medline and Scopus databases were search until February 1, 2017 and using randomized controlled trials comparing outcomes between different mesh fixation techniques were included. The results demonstrated that fifteen RCTs (n = 1783) were eligible for pooling. Five types of mesh fixation were used; metallic tack, no-fixation, absorbable tack, suture, and glue. Network meta-analysis that use metallic tack as the reference, indicated that suture and glue both carried a lower risk of recurrence with pooled risk ratios (RR) of 0.29 (95% CI 0.00, 18.81) and 0.29 (0.07, 1.30), respectively. For overall complications, absorbable tack had lower risk (0.63, 95% CI: 0.02, 16.13). However, none of these estimates reached statistical significance. So, this network meta-analysis suggests that glue and absorbable tack might be best in lowering recurrence risk and complications. However, a large scale RCT is still needed to confirm these results.

Primary umbilical endometriosis.

A 45-year old nulliparous woman presented with umbilical pigmented lesion with cyclical bleeding. The lesion was excised and pathological diagnosis was umbilical endometriosis. The authors reviewed the current literature and discussed the different diagnosis and management of umbilical endometriosis.