Does the abdominal entry method in laparoscopy really matter? A network meta-analysis of rare events in randomized trials.

OBJECTIVE

To evaluate the risk of major injuries associated with Veress, open (Hasson), direct and optical abdominal entry methods in laparoscopy.

METHODS

Network meta-analysis was performed using penalized logistic regression. Pairwise meta-analysis was carried-out using Bayesian binomial-normal hierarchical models with weakly informative priors. Risk of bias was evaluated by ROB-2 method. NMA protocol was recorded in PROSPERO (n. CRD42024583526).

RESULTS

Vascular lesions occurred in 14/2832 of Veress, 1/1661 of direct, 2/426 of optical and 0/2030 of open entry methods in 26 studies of 7250 laparoscopies. In NMA, direct and open entry methods were associated with a reduced risk of vascular lesions compared to Veress (OR = 0.17,95 %CI = 0.04-0.67 and OR = 0.09,95 %CI = 0.01-0.68,respectively). Overall, pooled rates of major injuries were 0.76/1000 (95 % CI = 0.06-2.05) in 29 studies of 7584 subjects. Major injuries were less common in direct as compared to either Veress (OR = 0.21,95 %CI = 0.08-0.56) or open method (OR = 0.23,95 %CI = 0.07-0.73). According to a ranking evaluation of absence of major complications, direct entry (SUCRA = 84.3 %) had the highest cumulative proportion of success, followed by optical entry (SUCRA = 68.5 %). Minor complications including extraperitoneal insufflation, multiple attempts, omental injury, trocar bleeding or infection or incisional hernia were studied in a network of 8984 subjects in 33 studies with a pooled prevalence of 30/1000 (95 %CI = 26.7-34.7). The risk of minor injuries was lower in direct (OR = 0.33,95 %CI = 0.23-0.46) as opposed to Veress entry. Direct entry was also the method with the lowest cumulative proportion of minor injuries (SUCRA = 97.75).

CONCLUSION

The open entrance method prevents vascular but not visceral injury. Overall, direct entry into the abdomen causes fewer severe and minor complications than Veress. In a hierarchy of procedures with fewer complications, direct entrance ranks first among the four most common methods of abdominal entry to establish pneumoperitoneum.