The Effect Of Artificial Pneumoperitoneum On Pleth Variability Index And Perfusion Index In Patient With General Aneasthesia

Background: Pneumoperitoneum induces a stress reaction in the human body which can adversely affect the respiratory and circulatory system.Therefore it is important to improve hemodynamics monitoring during pneumoperitoneum.During mechanical ventilation traditional non-invasive hemodynamics monitoring methods(including non-invasive blood pressure monitoring,pulse oximetry,non-invasive cardiac output monitoring)are inaccurate in reflecting the correct hemodynamic status of the patients.Pulse perfusion index(PI)and perfusion index variation(PVI)respectively measure the perfusion and hemodynamics status of a patient in a non-invasive way.These values rely on real-time changes in cardiac and respiratory functions.This study aims at investigating the effect of pneumoperitoneum and lateral decubitus position on PI and PVI.Methods: Patients undergoing elective surgery of the kidney or adrenal glands were enrolled for this study and randomly divide into two groups(n=20).One group was to undergo the traditional laparotomic surgery while the other group was to undergo laparoscopic surgery.Before induction of anesthesia an infusion of ringer's lactate 10ml/kg was given to the patients.After induction of anesthesia and intubation the patients were placed in lateral decubitus position as required and pneumoperitoneum was established.Hemodynamic values(including heart rate,mean arterial blood pressure,peak airway pressure,end tidal carbon dioxide,PI,PVI and narcotrend index)were recorded at these different time points :upon arrival in the operation room,before and 5 minutes after placement in lateral decubitus postion,before establishment of pneumoperitoneum(15 cm H2O)(or start of traditional laparotomy),5 minutes after start of pneumoperitoneum,every five minutes interval during surgery up to 10 mins after end of pneumoperitoneum.Results: There was no statistical difference between the two groups with regards to basic demographics of the patients,intraoperative bleeding,amount of liquids infused and urine output.Compared to the traditional group,there was a statistically significant increase in PVI,Ppeak,Pplat and MAP and a statistically significant decrease in PI.Intragroup analysis of the laparoscopic group revealed a statistically significant increase in PVI,Ppeak,Pplat,MAP and HR and a statistically significant decrease of PI after pneumoperitoneum was established.Conclusions: Establishment of pneumoperitoneum can cause a decrease in venous return to the heart which can lead to an increase in PVI.Under pneumoperitoneum an increase in PVI does not reflect the blood volume status of the patient.