[Effects of pneumoperitoneal pressure on air embolism duringlaparoscopic hepatectomy and degree of postoperative inflammation].

Objective: To investigate the incidence and severity of embolicevents, and degree of postoperative inflammation when pneumoperitoneal pressures 15 mmHg and 12 mmHg were used during laparoscopic hepatectomy. Methods: A computer-generated 1∶1 randomization protocol was used to assign fifty patients to either the 15 mmHg(P15, n =25) or 12 mmHg(P12, n =25) group. Throughout the surgery, air embolisms were detected by transesophageal echocardiography (TEE) and graded based on their size. Vital signs, arterial blood gases (ABG), P(ET)CO(2) levels, blood loss, operative time and postoperative hospital stays were monitored. 2 ml blood samples were taken before and after operation finished 0, 12 and 24 h by using EDTA anticoagulated tubes in order to detect the IL-6, TNF-α and IL-10 level in plasma. Results: CO(2) embolism occurred in 100% of the enrolled patients. The frequencies of severe air embolism were 76%( n =19) in P15 group and 52% ( n =13) in P12 group, respectively. The duration of severe embolism episodes in P15 group was much longer than that in P12 group[(58.0±22.6) s vs(36.6±17.8)s, t =3.71, P <0.01]. The incidence of complications in group P15 was 24%, which was higher than that in group P12 of 4%(χ(2)=4.15, P <0.05). The postoperative pro-inflammatory cytokine IL-6 and TNF-α in group P15 at the point of 12 hour after operation[685.66(435.18-935.52)ng/L, 31.00(18.29-41.15)ng/L]were statistically higher than those in group P12 [480.50(255.28-685.34) ng/L, 21.00(14.87-31.64) ng/L, P <0.05], whereas the anti-inflammatory cytokine IL-10 in P15 group[18.00(5.75-30.55) ng/L]was statistically lower than the P12 group [26.89(15.03-38.00) ng/L, P <0.05]. There was no statistical difference in operative time, blood loss and postoperative hospital stay between the two groups. Conclusion: The higher pneumoperitoneal pressure during laparoscopic hepatectomy causes more serious gas embolism, prolongs embolic duration and lead to more sever inflammatory response.