Cost-effectiveness of the prevention of adhesions and adhesive small bowel obstruction after colorectal surgery with adhesion barriers: a modelling study

Current Management of Adhesive Small Bowel Obstructions in Children

Adhesive small bowel obstructions are a common cause of morbidity in children who underwent prior abdominal surgery. The concept of partial versus complete bowel obstruction is outdated and lacks precision to be clinically useful. Identifying patients with indications for immediate operative intervention is critical and must be recognized to limit morbidity. Clinical protocols and contrast challenge algorithms have attempted to identify patients that will resolve their bowel obstruction nonoperatively; there has been slow uptake in the pediatric patient population versus adults until recently. Incorporating predictive models and standardized contrast challenge protocols will help reduce interpractitioner variability and improve clinical outcomes.

Adhesion-related readmissions after open and laparoscopic colorectal surgery in 16 524 patients

AIM

Colorectal surgery is associated with a high risk of adhesion formation and subsequent complications. Laparoscopic colorectal surgery reduces adhesion formation by 50%; however, the effect on adhesion-related complications is still unknown. This study aims to compare differences in incidence rates of adhesion-related readmissions after laparoscopic and open colorectal surgery.

METHOD

Population data from the Scottish National Health Service were used to identify patients who underwent colorectal surgery between June 2009 and June 2011. Readmissions were registered until December 2017 and categorized as being either directly or possibly related to adhesions, or as reoperations potentially complicated by adhesions. The primary outcome measure was the difference in incidence of directly adhesion-related readmissions between the open and laparoscopic cohort.

RESULTS

Colorectal surgery was performed in 16 524 patients; 4455 (27%) underwent laparoscopic surgery. Patients undergoing laparoscopic surgery were readmitted less frequently for directly adhesion-related complications, 2.4% (95% CI 2.0%-2.8%) versus 7.5% (95% CI 7.1%-7.9%) in the open cohort. Readmissions for possibly adhesion-related complications were less frequent in the laparoscopic cohort, 16.8% (95% CI 15.6%-18.0%) versus 21.7% (95% CI 20.9%-22.5%), as well as reoperations potentially complicated by adhesions, 9.7% (95% CI 8.9%-10.5%) versus 16.9% (95% CI 16.3%-17.5%).

CONCLUSION

Overall, any adhesion-related readmissions occurred in over one in three patients after open colorectal surgery and one in four after laparoscopic colorectal surgery. Compared with open surgery, incidence rates of adhesion-related complications decrease but remain substantial after laparoscopic surgery.

Transcriptome sequencing analysis of primary fibroblasts: a new insight into postoperative abdominal adhesion

PURPOSE

The specific genes or pathways in fibroblasts responsible for the pathogenesis of postoperative abdominal adhesion (PAA) remain to be elucidated. We aim to provide a new insight into disease mechanisms at the transcriptome level.

METHODS

Male Sprague-Dawley rats were used to establish a PAA model. Primary fibroblasts were separated from normal peritoneal tissue (NF) and postoperative adhesion tissue (PF). RNA sequencing was used to analyze the transcriptome in NF and PF.

RESULTS

One thousand two hundred thirty-five upregulated and 625 downregulated DEGs were identified through RNA-Seq. A pathway enrichment analysis identified distinct enriched biological processes, among which the most prominent was related to immune and inflammatory response and fibrosis. HE staining and Masson's trichrome staining histologically validated the RNA-Seq results. Six hub genes, ITGAM, IL-1β, TNF, IGF1, CSF1R and EGFR were further verified by RT-PCR.

CONCLUSIONS

Our study revealed the roles of the immune and inflammatory responses and fibrosis in the process of PAA. We also found six hub genes that may be potential therapeutic targets for PPA.

Clinical application of advances and innovation in radiation treatment of hepatocellular carcinoma

Background:

Hepatocellular carcinoma (HCC) management has evolved over the past two decades, with the development of newer treatment modalities. While various options are available, unmet needs are reflected through the mixed treatment outcome for intermediate-stage HCC. As HCC is radiosensitive, radiation therapies have a significant role in management. Radiation therapies offer local control for unresectable lesions and for patients who are not surgical candidates. Radiotherapy also provides palliation in metastatic disease, and acts as a bridge to resection and transplantation in selected patients. Advancements in radiotherapy modalities offer improved dose planning and targeted delivery, allowing for better tumor response and safer dose escalations while minimizing the risks of radiation-induced liver damage. Radiotherapy modalities are broadly classified into external beam radiation therapy and selective internal radiation therapy. With emerging modalities, radiotherapy plays a complementary role in the multidisciplinary care of HCC patients.

Aim:

We aim to provide an overview of the role and clinical application of radiation therapies in HCC management.

Relevance for Patients:

The continuous evolution of radiotherapy techniques allows for improved therapeutic outcomes while mitigating unwanted adverse effects, making it an attractive modality in HCC management. Rigorous clinical studies, quality research and comprehensive datasets will further its application in the present era of evidence-based practice in Medicine.

Hyaluronate carboxymethylcellulose sheets for the prevention of adhesive complications: a model-based cost-utility analysis

AIM

Clinical trials suggest that hyaluronate carboxymethylcellulose (HA/CMC) prevents adhesion-related complications after intra-abdominal surgery, but at a high upfront cost. This study evaluated the cost-effectiveness of HA/CMC for patients undergoing curative-intent open colorectal cancer surgery.

METHODS

Using a Markov Monte Carlo microsimulation model, we conducted a cost-utility analysis comparing the cost-effectiveness of HA/CMC at curative-intent open colorectal cancer surgery versus standard management. We considered a scenario where HA/CMC was used at the index operation only, as well as where it was used at the index operation and any subsequent operations. The perspective was that of the third-party payer. Costs and utilities were discounted 1.5% annually, with a 1-month cycle length and 5-year time horizon. Model input data were obtained from a literature review. Outcomes included cost, quality-adjusted life-years (QALYs), small bowel obstructions (SBOs) and operations for SBO.

RESULTS

Using HA/CMC at the index operation results in an incremental cost increase of CA$316 and provides 0.001 additional QALYs, for an incremental cost-effectiveness ratio of CA$310,000 per QALY compared to standard management. In our simulated cohort of 10,000 patients, HA/CMC prevented 460 SBOs and 293 surgeries for SBO. Probabilistic sensitivity analysis found that HA/CMC was cost-effective in 18.5% of iterations, at a cost-effectiveness threshold of CA$50,000 per QALY. Results of the scenario analysis where HA/CMC was used at the index operation and any subsequent operations were similar.

CONCLUSIONS

Hyaluronate carboxymethylcellulose prevents adhesive bowel obstruction after open colorectal cancer surgery but is unlikely to be cost-effective given minimal long-term impact on healthcare costs and QALYs.

Effectiveness of barrier agents for preventing postoperative bowel obstruction after laparoscopic surgery: a retrospective cohort study

PURPOSE

The effectiveness of using anti-adhesion agents in laparoscopic surgery is controversial. We compared the outcomes of patients exposed to anti-adhesion agents (barrier group) with those of patients not exposed (no barrier group) in laparoscopic surgery.

METHODS

Using a nationwide claim-based database in Japan, we analyzed data from patients who underwent laparoscopic surgery between 2005 and 2019 and compared the patient characteristics and the proportion of those with bowel obstruction between the barrier and no barrier groups. We also performed several sensitivity and subgroup analyses.

RESULTS

Of the 57,499 patients who met the inclusion criteria, 14,360 and 43,139 were assigned to the barrier and no barrier groups, respectively. The proportion of patients with a bowel obstruction in the two groups did not differ among all patients hospitalized for obstruction (1.1 vs. 1.1%, p = 0.63) and those requiring surgery (0.2 vs. 0.2%, p = 0.39). In the sensitivity analysis with propensity score matching, the incidences of bowel obstruction between the barrier and non-barrier groups were equivocal (1.3 vs. 1.6%), but statistically marginal (chi-square test, p = 0.035; log-rank test, p = 0.09).

CONCLUSION

The use of barrier agents for adhesive prevention did not show clear effectiveness for the prevention of bowel obstruction after laparoscopic surgery for unselected cases. Further studies focusing on more specific procedures are needed.

Efficacy and safety of Seprafilm for preventing intestinal obstruction after gastrointestinal neoplasms surgery: a systematic review and meta-analysis

OBJECTIVE

It was controversial that hyaluronate-carboxy-methylcellulose-based membrane (Seprafilm) could prevent intestinal obstruction after gastrointestinal neoplasms operation. This study aimed to evaluate the efficacy and safety of Seprafilm in preventing postoperative intestinal obstruction of gastrointestinal neoplasms patients.

METHODS

A systematic research of multiple databases was performed to identify relevant studies, and the studies satisfying the inclusion criteria were included. Risk ratio (RR), weighted mean difference (WMD), and 95% confidence intervals were calculated using RevMan 5.3.

RESULTS

2937 patients from 10 studies who were enrolled in this meta-analysis were divided into the Seprafilm group (n = 1334) and the control group (n = 1603). The Seprafilm group had lower incidence of intestinal obstruction (RR, 0.52; 95% CI, 0.38-0.70; p < .0001), reoperation rates due to intestinal obstruction (RR, 0.48; 95% CI, 0.28 - 0.80; p = .005), incidence of overall complications (RR, 0.77; 95% CI, 0.61-0.97; p = .03) and higher serum creatinine on postoperative day 5 (WMD, 0.15; 95% CI, 0.05-0.25; p = .003). There were no differences regarding time to intestinal obstruction after operation, aspartate aminotransferase, alanine aminotransferase, blood urea nitrogen, white blood cell count results on day 5 and 7, serum creatinine on day 7, hospital stay, and incidence of intra-abdominal infection, wound infection, anastomotic leakage between the 2 groups.

CONCLUSIONS

This meta-analysis provided valuable evidence-based support for the efficacy and safety of Seprafilm in preventing postoperative intestinal obstruction of gastrointestinal neoplasms patients. However, more multicenter randomized controlled trials from different countries are needed.

A Randomized Controlled Trial of Thermo-Sensitive Sol-Gel Anti-Adhesion Agent after Gynecologic Surgery

Postoperative abdominal adhesions can lead to several adverse consequences such as pelvic pain, bowel obstruction, and infertility. We aimed to explore the anti-adhesion efficacy and safety of a thermo-sensitive sol-gel agent in patients who receive abdominopelvic surgery for benign gynecologic disease. This study was a randomized, controlled, single-blind clinical trial of women undergoing benign gynecologic surgery between January 2017 and December 2017. The patients were randomly assigned to three groups with a 1:1:1 ratio: experimental group (received the thermo-sensitive sol-gel agent), control group (untreated), and comparator group (received 4% icodextrin). Patients were followed for 4 weeks postoperatively, and efficacy was evaluated by performing the visceral slide test to identify adhesion formation. In total, 183 patients were enrolled in the study, and 178 (97.3%) completed the trial. The incidence rate of abdominal adhesion formation was significantly lower in the experimental group than in the control group (7.9% vs. 21.1%, p = 0.040); however, it was similar between the experimental and comparator groups (7.9% vs. 13.8%. p = 0.299). At 4 weeks, no differences in adhesion-related symptoms were observed between the experimental and control groups. Adverse events were mostly mild and did not differ significantly among the three groups (p = 0.375). In conclusion, use of a thermo-sensitive sol-gel agent was safe and effective to prevent abdominal adhesions after benign gynecologic surgeries.

Adhesion reformation and the limited translational value of experiments with adhesion barriers: A systematic review and meta-analysis of animal models

Today, 40-66% of elective procedures in general surgery are reoperations. During reoperations, the need for adhesiolysis results in increased operative time and a more complicated convalescence. In pre-clinical evaluation, adhesion barriers are tested for their efficacy in preventing 'de novo' adhesion formation, However, it is unknown to which extent barriers are tested for prevention of adhesion reformation. The aim of this systematic review and meta-analysis is to assess the efficacy of commercially available adhesion barriers and laparoscopic adhesiolysis in preventing adhesion reformation in animal models. Pubmed and EMBASE were searched for studies which assessed peritoneal adhesion reformation after a standardized peritoneal injury (in the absence of an intra-peritoneal mesh), and reported the incidence of adhesions, or an adhesion score as outcome. Ninety-three studies were included. No study met the criteria for low risk of bias. None of the commercially available adhesion barriers significantly reduced the incidence of adhesion reformation. Three commercially available adhesion barriers reduced the adhesion score of reformed adhesions, namely Seprafilm (SMD 1.38[95% CI]; p < 0.01), PEG (SMD 2.08[95% CI]; p < 0.01) and Icodextrin (SMD 1.85[95% CI]; p < 0.01). There was no difference between laparoscopic or open adhesiolysis with regard to the incidence of adhesion reformation (RR 1.14[95% CI]; p ≥ 0.05) or the adhesion score (SMD 0.92[95% CI]; p ≥ 0.05). Neither currently commercially available adhesion barriers, nor laparoscopic adhesiolysis without using an adhesion barrier, reduces the incidence of adhesion reformation in animal models. The methodological quality of animal studies is poor.