Evaluation of surgical condition during laparoscopic gynaecological surgery in patients with moderate vs. deep neuromuscular block in low-pressure pneumoperitoneum.

Introduction: The significant effect of deep neuromuscular block (NMB) in laparoscopic surgery is still controversial, especially in lower-pressure pneumoperitoneum. This study investigates the effect of deep neuromuscular block on intraabdominal pressure (IAP), surgical space quality, post-operative abdominal pain, and shoulder tip pain in laparoscopic gynaecological surgery.

Material and methods: This is a randomised, double-blinded control trial which randomised samples to moderate NMB (train-of-four count [TOF] of 1 or 2) or deep NMB (post-tetanic count [PTC] of 1 or 2). Surgery began with IAP 8 mmHg but was allowed to increase the pressure if the surgical condition was unfavourable. The surgical condition was rated on a 4-point scale. Post-operative abdominal pain and shoulder tip pain was assessed using a numerical rating scale for pain, with 0 defined as no pain and 10 severe pain at recovery area (time 0), 30 minutes, and 24 hours post-operation.

Results: Seventy patients completed the study. The rate of increasing IAP between the 2 groups ( P = 0.172) is not significant, but deep NMB requires less pressure - mean highest IAP of 10.31 (± 1.39) mmHg, moderate NMB 11.54 (± 1.69) mmHg. The mean surgical space condition score was significantly better in the deep NMB group at 2.4 (± 0.7) compared to moderate NMB at 3.2 (± 0.66), P < 0.005. There was a significantly lower post-operative abdominal pain score in deep NMB but no significant difference in shoulder tip pain score between the 2 groups.

Conclusions: Deep NMB enables the usage of lower IAP in laparoscopic surgery without interfering with surgical space condition, and it reduces the post-operative abdominal pain score in 24 hours compared to moderate NMB.