Effect of pneumoperitoneum on cardiac output and gasrtic inramucosal PHi in obese and nonobese patients

ABSTRACT

This study was designed to investigate the effect of pneumoperitoneum [PP] on cardiac output [CO] and gastric intramucosal PHi [PHi is the predictor of splanchnic blood flow] in obese and non obese patients under general anesthesia. Thirty patients scheduled for laparoscopy cholecystectomy divided according to their body mass index >/= 30kg/m[2] obese and < 30kg/m[2] non- obese into 2 groups. After anesthesia and intubation, gastric tonometer catheter was inserted into the stomach and gastric intramucosal PHi was measured at 20 min after induction [baseline], 20 min after pneumoperitoneum [PP] and 15 mm after desuflation. Patients haemodynamic parameters were measured non invasively. Stroke volume [SV], heart rate [HR], cardiac output [CO] and mean arterial blood pressure [MABP] were recorded at 20min after induction [base line value], 2 and 20min after PP and 15min after desuflation. In this study we observed significant increase in MABP and HR in obese and non obese patients after PP. In both groups SV was significantly reduced after PP. Cardiac output [CO] was significantly increased at 2 and 20min after PP in obese patients while non obese patients experienced biphasic pattern in CO i.e. initial decrease at 2 min after PP., followed by gradual restoration of CO at 20mm after PP. At 15 min after desuflation CO started to return near to its base line value in both groups. The gastric intramucosal PHi mean values were insignificantly reduced at 20 min after PP and they were within the normal limit and start to return to its base line mean value at 15 min after desuflation in both obese and non obese patients. In conclusion pneumoperitoneum at 12minHg did not affect gasric intramucosal PHi i.e. splanchnic blood flow in obese and non obese patients. Moreover, the gastric intramucosal PHi was not affected by the changes in the cardiac output. Furthermore, obese patients well tolerated pneumoperitoneum without experiencing fall in cardiac output as that noticed in non obese patients who have a biphasic pattern of cardiac output during pneumoperitoneum [initial decrease followed by partial restoration and increase in CO]