The effects of hypervolemic infusion on microcirculation perfusion of patients during laparoscopic colorectal surgery.

The aim of this study is to assess the effects of hypervolemic infusion with different solutions on microcirculation perfusion during laparoscopic colorectal surgery.Thirty-six patients were randomly divided into Ringer lactate solution [RL] group, succinylated gelatin injection [Gel] group, and hypertonic saline hydroxyethyl starch 40 injection [HS] group. Hypervolemic infusion was performed during the induction period of general anesthesia. Arterial blood-gas parameters, noninvasive hemodynamics, gastric tonometry values, and central venous pressure (CVP) were compared at baseline (T1); the end of hypervolemic infusion (T2); 5 min (T3), 15 min (T4), 30 min (T5), and 60 min (T6) during pneumoperitoneum; 5 min (T7), 15 min (T8), and 25 min (T9) after pneumoperitoneum. Patients were also grouped by age for further comparisons.The hematocrit levels of all groups after T2 decreased. The gastric mucosal-arterial carbon dioxide partial pressure (Pg-aCO2) started to decrease after T2 and rebounded after T5. There was no difference in the gastric mucosal perfusion when compared between 3 groups. The blood Na of HS group increased significantly after T2, then gradually restored and returned to baseline by T8. The plasma bicarbonate (HCO3) levels of RL and Gel groups elevated from T2 to T7, after which they started to decrease, but this phenomenon was not significant in HS group. In both RL and Gel groups, blood pressure has a significant fluctuation in elder patients.Hypervolemic infusion of these solutions during the induction of anesthesia can improve gastric mucosal perfusion. HS can maintain a more stable hemodynamic effect when used with caution in patients with preoperative hypernatremia.