Effect Of Trendelenburg Position Combined With Pneumoperitoneum On Cerebral Blood Flow Changes During Laparoscopic Gynecological Surgery

Objective In addition to CO2 pneumoperitoneum,patients with benign uterine lesions need to perform laparoscopic surgery at the Trendelenburg position to meet the surgical needs.Prolonged pneumoperitoneum combined with Trendelenburg position can affect cerebral blood flow and cause cerebral oxygen metabolism disorder.Regional cerebral oxygen saturation(r SO2)monitor has the advantages of intuitionistic,real-time and continuous monitoring of cerebral oxygen metabolism,which is one of the better means to detect cerebral oxygen metabolism disorder in clinical practice.Optic nerve sheath diameter(ONSD)was measured noninvasively by ultrasound,which indirectly reflected intracranial pressure(ICP)by increasing the diameter of optic nerve sheath.This study aims to explore the influencing factors of cerebral blood flow changes in patients with pneumoperitoneum combined with Trendelenburg postural position during laparoscopic gynecological surgery through changes in brain tissue oxygen metabolism and intracranial pressure.Methods A total of 60 patients who planned to undergo laparoscopic total hysterectomy in chaohu hospital affiliated of anhui medical university from January 2018 to December 2018 were randomly selected,aged 44-60 yr,of American Society of Anesthesiologists physical status ?~?.Excluding patients with severe hypertension,diabetes,abnormal heart function;Severe liver and kidney dysfunction,asthma or chronic obstructive pulmonary disease,cerebral hemorrhage,transient ischemic attack,subarachnoid hemorrhage and other brain diseases history.Near-infrared spectroscopy(NIRS)was used to continuously monitor r SO2 at 6 time points including 10 minutes after anesthesia induction(supine position)(T0),pneumoperitoneum combined with Trendelenburg position immediately(T1),for 30 min(T2),for 60 min(T3),for 90 min(T4)and 10 min after restoration of supine position(T5).T0 was taken as the base value to clarify the balance of cerebral oxygen supply and demand during operation.ONSD was measured noninvasively by ultrasound at 6 time points,and the changes of ICP were indirectly reflected by monitoring the widening degree of optic nerve sheath in patients during surgery.MAP,CVP and Pa CO2 PETCO2,Sp O2 and HR of corresponding time points are recorded simultaneously.The changes of r SO2 and ONSD during gynecological laparoscopic surgery were analyzed,as well as the relationship between r SO2 and MAP,Pa CO2,PETCO2 and HR.Results In gynecological laparoscopic surgery,r SO2 increased gradually with the extension of the time of Trendelenburg position and pneumoperitoneum,from the basic value(left 67.5±5.2,right 67.3±4.4)% to the Trendelenburg position for 30min(left 76.6±5.5,right 76.6±5.3)%,the difference was statistically significant(P<0.05).The difference between r SO2 on the left and r SO2 on the right was not statistically significant(P>0.05).After pneumoperitoneum,the low immediate ONSD increased from the base value of(4.6±0.3)mm to(5.5±0.4)mm,the difference was statistically significant(P<0.05).For the first 30 min,the MAP value increased from the base value(83.5±7.0)mm Hg to(99.7±8.2)mm Hg,with statistically significant difference(P<0.05).Pa CO2 increased from 37.1±3.1 mm Hg to 46.8±3.4 mm Hg(P<0.05).After restoring supine position for 10 min,r SO2,ONSD,and MAP all dropped to the basic values.Conclusion In gynecological laparoscopic surgery,Trendelenburg position combined with artificial pneumoperitoneum resulted in brain overperfusion in patients,and immediate intracranial pressure increased significantly in the lower part of the head,but it was still within the range of brain automatic regulation.The changes of cerebral blood flow in patients were related to MAP and Pa CO2,but were not significantly related to HR and Sp O2.