Primary entry trocar design and entry-related complications at laparoscopy in obese patients: meta-analysis

Background: Safe primary entry at laparoscopy could present challenges in obese patients. Various techniques have been proposed in previous studies, however, the characteristics of the actual device utilized may be more influential than the technique in achieving successful abdominal entry in patients with increased BMI. Methods: This systematic review and meta-analysis included both randomized and non-randomized studies gathered with no date filters from MEDLINE, Embase, Scopus, Web of Science and Clinicaltrials.gov. PRISMA guidelines underpinned the conduct and reporting of the review. The meta-analysis of proportions was conducted using a generalized linear mixed model and analyses included random-effects models. The primary outcome was the proportion of first access vascular and visceral injuries incurred in the process of laparoscopic abdominal surgery in patients with a BMI >30kg/m(2). Subgroup analysis was performed for optical versus non-optically enabled devices. Results: In total, 5403 patients were analysed across 13 observational studies with a mean BMI of 45.93kg/m(2). In 216 patients from two randomized studies, the mean BMI was 39.92kg/m(2). The overall incidence using a random-effects model was 8.1 per 1000 events of visceral and vascular injuries (95 per cent c.i. 0.003 to 0.024). Heterogeneity was statistically significant at I-2 = 80.5 per cent (69.6 per cent; 87.5 per cent, P< 0.0001). In a subgroup analysis, a tendency towards reduced injuries when optical devices were employed was observed with one per 100 injuries in these trocars (95 per cent c.i. 0.001 to 0.018) versus four per 100 (95 per cent c.i. -0.019 to -0.102) in non-optically enabled devices. Conclusion: Injuries during primary laparoscopic entry undertaken in obese patient groups are uncommon. Due to considerable heterogeneity in the small number of examined studies, evidence was insufficient and largely of low quality to ascribe differences in the incidence of injuries to the characteristics of the primary entry trocar utilized.