A Cochrane review included 17 studies with a total of 3 040 subjects. Overall there was no evidence of advantage using any single technique in terms of preventing major complications. However, there were two advantages with direct-trocar entry when compared with Veress-Needle entry, in terms of avoiding extraperitoneal insufflation (OR 0.06, 95% CI 0.02 to 0.23) and failed entry (OR 0.22, 95% CI 0.08 to 0.56). There was also an advantage with radially expanding access system (STEP) trocar entry when compared with standard trocar entry, in terms of trocar site bleeding (OR 0.06, 95% CI 0.01 to 0.46). Finally, there was an advantage of not lifting the abdominal wall before Veress-Needle insertion when compared to lifting in terms of failed entry without an increase in the complication rate (OR 5.17, 95% CI 2.24 to 11.90). However, studies were limited to small numbers, excluding many patients with previous abdominal surgery and women with a raised body mass index, who often had unusually high complication rates.
Comment: The quality of evidence is downgraded by inconsistency (heterogeneity in interventions and outcomes).