Shahjahan Khan

Early versus traditional postoperative feeding in patients undergoing resectional gastrointestinal surgery: A meta-analysis

BACKGROUND A meta-analysis evaluating surgical outcomes following nutritional provision provided proximal to the anastomosis within 24 hours of gastrointestinal surgery compared with traditional postoperative management was conducted. METHODS Databases were searched to identify randomized controlled trials comparing the outcomes of early and traditional postoperative feeding. Trials involving gastrointestinal tract resection followed by patients receiving nutritionally significant oral or enteral intake within 24 hours after surgery were included for analysis. RESULTS Fifteen studies involving a total of 1240 patients were analyzed. A statistically significant reduction (45%) in relative odds of total postoperative complications was seen in patients receiving early postoperative feeding (odds ratio [OR] 0.55; confidence interval [CI], 0.35 -0.87, P = .01). No effect of early feeding was seen with relation to anastomotic dehiscence (OR 0.75; CI, 0.39-1.4, P = .39), mortality (OR 0.71; CI, 0.32-1.56, P = .39), days to passage of flatus (weighted mean difference [WMD] -0.42; CI, -1.12 to 0.28, P = .23), first bowel motion (WMD -0.28; CI, -1.20 to 0.64, P = .55), or reduced length of stay (WMD -1.28; CI, -2.94 to 0.38, P = .13); however, the direction of clinical outcomes favored early feeding. Nasogastric tube reinsertion was less common in traditional feeding interventions (OR 1.48; CI, 0.93-2.35, P = .10). CONCLUSIONS Early postoperative nutrition is associated with significant reductions in total complications compared with traditional postoperative feeding practices and does not negatively affect outcomes such as mortality, anastomotic dehiscence, resumption of bowel function, or hospital length of stay.

Meta-Analysis of Randomized Clinical Trials Comparing Open and Laparoscopic Anti-Reflux Surgery

OBJECTIVES:The aim of this study was to conduct a meta-analysis of randomized evidence to determine the relative merits of laparoscopic anti-reflux surgery (LARS) and open anti-reflux surgery (OARS) for proven gastro-esophageal reflux disease (GERD).METHODS:A search of the Medline, Embase, Science Citation Index, Current Contents, and PubMed databases identified all randomized clinical trials that compared LARS and OARS and that were published in the English language between 1990 and 2007. A meta-analysis was carried out in accordance with the QUOROM (Quality of Reporting of Meta-Analyses) statement. The six outcome variables analyzed were operating time, hospital stay, return to normal activity, perioperative complications, treatment failure, and requirement for further surgery. Random-effects meta-analyses were carried out using odds ratios (ORs) and weighted mean differences (WMDs).RESULTS:Twelve trials were considered suitable for the meta-analysis. A total of 503 patients underwent OARS and 533 had LARS. For three of the six outcomes, the summary point estimates favored LARS over OARS. There was a significant reduction of 2.68 days in the duration of hospital stay for the LARS group compared with that for the OARS group (WMD: −2.68, 95% confidence interval (CI): −3.54 to −1.81; P<0.0001), a significant reduction of 7.75 days in return to normal activity for the LARS group compared with that for the OARS group (WMD: −7.75, 95% CI: −14.37 to −1.14; P=0.0216), and finally, there was a statistically significant reduction of 65% in the relative odds of complication rates for the LARS group compared with that for the OARS group (OR: 0.35, 95% CI: 0.16–0.75; P=0.0072). The duration of operating time was significantly longer (39.02 min) in the LARS group (WMD: 39.02, 95% CI: 17.99–60.05; P=0.0003). Treatment failure rates were comparable between the two groups (OR: 1.39, 95% CI: 0.71–2.72; P=0.3423). Despite this, the requirement for further surgery was significantly higher in the LARS group (OR: 1.79, 95% CI: 1.00–3.22; P=0.05).CONCLUSIONS:On the basis of this meta-analysis, the authors conclude that LARS is an effective and safe alternative to OARS for the treatment of proven GERD. LARS enables a faster convalescence and return to productive activity, with a reduced risk of complications and a similar treatment outcome, than an open approach. However, there is a significantly higher rate of re-operation (79%) in the LARS group.

Advances in the meta-analysis of heterogeneous clinical trials I: The inverse variance heterogeneity model

This article examines an improved alternative to the random effects (RE) model for meta-analysis of heterogeneous studies. It is shown that the known issues of underestimation of the statistical error and spuriously overconfident estimates with the RE model can be resolved by the use of an estimator under the fixed effect model assumption with a quasi-likelihood based variance structure - the IVhet model. Extensive simulations confirm that this estimator retains a correct coverage probability and a lower observed variance than the RE model estimator, regardless of heterogeneity. When the proposed IVhet method is applied to the controversial meta-analysis of intravenous magnesium for the prevention of mortality after myocardial infarction, the pooled OR is 1.01 (95% CI 0.71-1.46) which not only favors the larger studies but also indicates more uncertainty around the point estimate. In comparison, under the RE model the pooled OR is 0.71 (95% CI 0.57-0.89) which, given the simulation results, reflects underestimation of the statistical error. Given the compelling evidence generated, we recommend that the IVhet model replace both the FE and RE models. To facilitate this, it has been implemented into free meta-analysis software called MetaXL which can be downloaded from www.epigear.com.

Effect of timing of pharmaconutrition (immunonutrition) administration on outcomes of elective surgery for gastrointestinal malignancies: A systematic review and meta-analysis

BACKGROUND Pharmaconutrition has previously been reported in elective surgery to reduce postoperative infective complications and duration of hospital length of stay. OBJECTIVE To update previously published meta-analyses and elucidate potential benefits of providing arginine-dominant pharmaconutrition in surgical patients specifically with regard to the timing of administration of pharmaconutrition. DESIGN Randomized controlled trials comparing the use of pharmaconutrition with standard nutrition in elective adult surgical patients between 1980 and 2011 were identified. The meta-analysis was prepared in accordance with Preferred Reporting of Systematic Reviews and Meta-Analyses (PRISMA) recommendations. RESULTS Twenty studies yielding 21 sets of data met inclusion criteria. A total of 2005 patients were represented (pharmaconutrition, n = 1010; control, n = 995), in whom pharmaconutrition was provided preoperatively (k = 5), perioperatively (k = 2), or postoperatively (k = 14). No differences were seen in postoperative mortality with the provision of pharmaconutrition irrespective of timing of administration. Statistically significant reductions in infectious complications and length of stay were found with perioperative and postoperative administration. Perioperative administration was also associated with a statistically significant reduction in anastomotic dehiscence, whereas a reduction in noninfective complications was demonstrated with postoperative administration. Preoperative pharmaconutrition demonstrated no notable advantage over standard nutrition provision in any of the clinical outcomes assessed. CONCLUSIONS This meta-analysis highlights the importance of timing as a clinical consideration in the provision of pharmaconutrition in elective gastrointestinal surgical patients and identifies areas where further research is required.

Advances in the meta-analysis of heterogeneous clinical trials II: The quality effects model

This article examines the performance of the updated quality effects (QE) estimator for meta-analysis of heterogeneous studies. It is shown that this approach leads to a decreased mean squared error (MSE) of the estimator while maintaining the nominal level of coverage probability of the confidence interval. Extensive simulation studies confirm that this approach leads to the maintenance of the correct coverage probability of the confidence interval, regardless of the level of heterogeneity, as well as a lower observed variance compared to the random effects (RE) model. The QE model is robust to subjectivity in quality assessment down to completely random entry, in which case its MSE equals that of the RE estimator. When the proposed QE method is applied to a meta-analysis of magnesium for myocardial infarction data, the pooled mortality odds ratio (OR) becomes 0.81 (95% CI 0.61-1.08) which favors the larger studies but also reflects the increased uncertainty around the pooled estimate. In comparison, under the RE model, the pooled mortality OR is 0.71 (95% CI 0.57-0.89) which is less conservative than that of the QE results. The new estimation method has been implemented into the free meta-analysis software MetaXL which allows comparison of alternative estimators and can be downloaded from www.epigear.com.

Simulation comparison of the quality effects and random effects methods of meta-analysis

This is an editorial note/letter on Simulation Comparison of the Quality Effects and Random Effects Methods of Metaanalysis.

Suture cruroplasty versus prosthetic hiatal herniorrhaphy for large hiatal hernia: a meta-analysis and systematic review of randomized controlled trials

Objective:The aim was to conduct a meta-analysis of randomized controlled trials (RCTs) comparing 2 methods of hiatal closure for large hiatal hernia and to evaluate their strengths and flaws. Methods:Prospective RCTs comparing suture cruroplasty versus prosthetic hiatal herniorrhaphy for large hiatal hernia were selected by searching PubMed, Medline, Embase, Science Citation Index, Current Contents, and the Cochrane Central Register of Controlled Trials published between January 1991 and October 2014. The outcome variables analyzed included operating time, complications, recurrence of hiatal hernia or wrap migration, and reoperation. These outcomes were unanimously decided to be important because they influence the practical approach toward patient management. Random effects model was used to calculate the effect size of both dichotomous and continuous data. Heterogeneity among the outcome variables of these trials was determined by the Cochrans Q statistic and I2 index. The meta-analysis was prepared in accordance with Preferred Reporting of Systematic Reviews and Meta-Analyses guidelines. Results:Four RCTs were analyzed totaling 406 patients (Suture = 186, Prosthesis = 220). For only 1 of the 4 outcomes, ie, reoperation rate (OR 3.73, 95% CI 1.18, 11.82, P = 0.03), the pooled effect size favored prosthetic hiatal herniorrhaphy over suture cruroplasty. For other outcomes, comparable effect sizes were noted for both groups which included recurrence of hiatal hernia or wrap migration (OR 2.01, 95% CI 0.92, 4.39, P = 0.07), operating time (SMD −0.46, 95% CI −1.16, −0.24, P = 0.19) and complication rates (OR 1.06, 95% CI 0.45, 2.50, P = 0.90). Conclusions:On the basis of our meta-analysis and its limitations, we believe that the prosthetic hiatal herniorrhaphy and suture cruroplasty produces comparable results for repair of large hiatal hernias. In the future, a number of issues need to be addressed to determine the clinical outcomes, safety, and effectiveness of these 2 methods for elective surgical treatment of large hiatal hernias. Presently, the use of prosthetic hiatal herniorrhaphy for large hiatal hernia cannot be endorsed routinely and the decision for the placement of mesh needs to be individualized based on the operative findings and the surgeons recommendation.

Systematic Review and Meta-Analysis of Perioperative Outcomes of Peroral Endoscopic Myotomy (POEM) and Laparoscopic Heller Myotomy (LHM) for Achalasia.

Aims and Objectives: Laparoscopic Heller myotomy (LHM) is the preferred surgical method for treating achalasia. However, peroral endoscopic myotomy (POEM) is providing good short-term results. The objective of this systematic review and meta-analysis was to compare the safety and efficacy of LHM and POEM. Materials and Methods: A search of PubMed, Cochrane database, Medline, Embase, Science Citation Index, and current contents for English-language articles comparing LHM and POEM between 2007 and 2016 was performed. Variables analyzed included prior endoscopic treatment, prior medical treatment, prior Heller myotomy, operative time, overall complications rate, postoperative gastroesophageal reflux disease (GERD), length of hospital stay, postoperative pain score, and long-term GERD. Results: Seven trials consisting of 483 (LHM=250, POEM=233) patients were analyzed. Preoperative variables, for example, prior endoscopic treatment [odds ratio (OR), 1.32; 95% confidence interval (CI), 0.23-4.61; P=0.96], prior medical treatment [weighted mean difference (WMD), 1.22; 95% CI, 0.52-2.88; P=0.65], and prior Heller myotomy (WMD, 0.47; 95% CI, 0.13-1.67; P=0.25) were comparable. Operative time was 26.28 minutes, nonsignificantly longer for LHM (WMD, 26.28; 95% CI, −11.20 to 63.70; P=0.17). There was a comparable overall complication rate (OR, 1.25; 95% CI, 0.56-2.77; P=0.59), postoperative GERD rate (OR, 1.27; 95% CI, 0.70-2.30; P=0.44), length of hospital stay (WMD, 0.30; 95% CI, −0.24 to 0.85; P=0.28), postoperative pain score (WMD, −0.26; 95% CI, −1.58 to 1.06; P=0.70), and long-term GERD (WMD, 1.06; 95% CI, 0.27-4.1; P=0.08) for both procedures. There was a significantly higher short-term clinical treatment failure rate for LHM (OR, 9.82; 95% CI, 2.06-46.80; P<0.01). Conclusions: POEM compares favorably to LHM for achalasia treatment in short-term perioperative outcomes. However, there was a significantly higher clinical treatment failure rate for LHM on short-term postoperative follow-up. Presently long-term postoperative follow-up data for POEM beyond 1 year are unavailable and eagerly awaited.

Carbon dioxide versus air insufflation for elective colonoscopy: A meta-analysis and systematic review of randomized controlled trials

Aims and Objective: The aim of this study was to conduct a meta-analysis and systematic review of randomized controlled trials (RCTs) comparing 2 methods of colonic insufflation for elective colonoscopy, that is, carbon dioxide (CO2) or air, and to evaluate their efficiency, safety, and side effects. Materials and Methods: Prospective RCTs comparing CO2 versus air insufflation for colonic distension during colonoscopy were selected by searching PubMed, Medline, Embase, Science Citation Index, Current Contents, and the Cochrane Central Register of Controlled Trials published between January 1980 and October 2014.The outcome variables analyzed included procedural and immediate postprocedural pain (during, end, or within 15 min after procedure), early postprocedural pain (between 30 and 120 min), intermediate postprocedural pain (360 min) and late postprocedural pain (720 to 1140 min), cecal/ileal intubation rate, cecal/ileal intubation time, and total colonoscopy examination time. These outcomes were unanimously decided to be important as they influence the practical approach toward patient management within and outside of hospital. Random effects model was used to calculate the effect size of both binary and continuous data. Heterogeneity among the outcome variables of these trials was determined by the Cochran Q statistic and I2 index. The meta-analysis was prepared in accordance with PRISMA guidelines. Results: Twenty-four RCTs totaling 3996 patients (CO2=2017, Air=1979) were analyzed. Statistically significant differences for the pooled effect size were observed for procedural and immediate postprocedural pain [weighted mean difference (WMD)=0.49; 95% confidence interval (CI), 0.32, 0.73; P=0.0005], early postprocedural pain between 30 and 120 minutes (WMD=0.25; 95% CI, 0.12, 0.49; P<0.0001), intermediate postprocedural pain, that is, 360 minutes after completion (WMD=0.35; 95% CI, 0.23, 0.52; P<0.0001), and late postprocedural pain between 720 and 1440 minutes (WMD=0.53; 95% CI, 0.34, 0.84; P=0.0061). Comparable effects were noted for cecal/ileal intubation rate (WMD=0.86; 95% CI, 0.61, 1.22; P=0.3975), cecal/ileal intubation time (WMD=−0.64; 95% CI, −1.38, 0.09; P=0.0860), and total examination time (WMD=−0.20; 95% CI, −0.96, 0.57; P=0.6133). Conclusions: On the basis of our meta-analysis and systematic review, we conclude that CO2 insufflation significantly reduces abdominal pain during and following the procedure lasting up to 24 hours. There is no difference in the cecal/ileal intubation rate and time and total examination time between the 2 methods. CO2 retention with CO2 insufflation during and after the colonoscopy shows inconsequential variation compared with air insufflation and has no adverse effect on patients. CO2 instead of air should be routinely utilized for colonoscopy.

Weight loss outcomes in laparoscopic vertical sleeve gastrectomy (LVSG) versus laparoscopic Roux-en-Y gastric bypass (LRYGB) procedures: a meta-analysis and systematic review of randomized controlled trials

Purpose: Laparoscopic Roux-en-Y gastric bypass (LRYGB) and laparoscopic vertical sleeve gastrectomy (LVSG) have been proposed as cost-effective strategies to manage morbid obesity. The aim of this meta-analysis was to compare the postoperative weight loss outcomes reported in randomized control trials (RCTs) for LVSG versus LRYGB procedures. Material and Methods: RCTs comparing the weight loss outcomes following LVSG and LRYGB in adult population between January 2000 and November 2015 were selected from PubMed, Medline, Embase, Science Citation Index, Current Contents, and the Cochrane database. The review was prepared in accordance with Preferred Reporting of Systematic Reviews and Meta-Analyses (PRISMA). Results: Nine unique RCTs described over 10 publications involving a total of 865 patients (LVSG, n=437; LRYGB, n=428) were analyzed. Postoperative follow-up ranged from 3 months to 5 years. Twelve-month excess weight loss (EWL) for LVSG ranged from 69.7% to 83%, and for LRYGB, ranged from 60.5% to 86.4%. A number of studies reported slow weight gain between the second and third years of postoperative follow-up ranging from 1.4% to 4.2%EWL. This trend was seen to continue to 5 years postoperatively (8% to 10%EWL) for both procedures. Conclusions: In conclusion, LRYGB and LVSG are comparable with regards to the weight loss outcomes in the short term, with LRYGB achieving slightly greater weight loss. Slow weight recidivism is observed after the first postoperative year following both procedures. Long-term reporting of outcomes obtained from well-designed studies using intention-to-treat analyses are identified as a major gap in the literature at present.