Does suppression of Trendelenburg position and pneumoperitoneum-induced intracranial pressure rise decrease the incidence of nausea and vomiting after gynecologic laparoscopic surgery: a randomized controlled study
Description
The elevated intracranial pressure (ICP) caused by Trendelenburg position (TP) and pneumoperitoneum (PP) is believed to increase the incidence of nausea and vomiting (PONV) after gynecological laparoscopic surgery, but there is a lack of direct evidence. Ultrasound measurement of optic nerve sheath diameter (ONSD) is a noninvasive examination that dynamically reflects ICP trends in patients. Therefore, the purpose of this experiment was to investigate the trend of ICP as evaluated by ONSD in gynecological laparoscopic surgery, as well as the effect of low-dose of mannitol pre- and post-treatment on ICP and PONV. Patients undergoing elective gynecological laparoscopic surgery were randomly assigned to one of three groups: Placebo group (1.25 ml/kg 0.9% saline as control); Mannitol_post group (20% mannitol at 0.25 g/kg 10 mins after TP and PP); or Mannitol_pre group (the same dose of mannitol before TP and PP). The primary outcome was the incidence of PONV within the first 24 h after surgery. The incidence and the proportion of moderate and severe PONV were significantly reduced in Mannitol_post and Mannitol_pre group than in Placebo group. Compared with Placebo group, Mannitol_post and Mannitol_pre group had significantly lower ONSDs and ONSDmax-T0 after PP. The ROC analysis revealed that ONSDmax-T0 significantly correlated with the occurrence of moderately and severe PONV at 24 h after surgery, with an AUC of 0.704 (95% CI 0.591 to 0.817), specificity 93%, and sensitivity 46.2%. Both post- and pre-treatment with low-dose of mannitol reduced the degree of ICP elevation in patients as determined by ONSD, as well as the incidence and severity of PONV, and to improve recovery quality. In laparoscopic gynecologic surgery, ONSDmax-T0 is associated with 24-hour PONV, and low-dose of mannitol can be used to prevent PONV after surgery.