Effects of open-lung strategy on postoperative delirium in elderly patients undergoing laparoscopic surgery / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the effect of open-lung strategy (OLS) on postoperative delirium (POD) in elderly patients undergoing laparoscopic surgery.Methods:Seventy-four elderly patients of both sexes, aged 65-80 yr, with body mass index of 18.5-30.0 kg/m 2, of American Society of Anesthesiologists Physical Status classification Ⅱ or Ⅲ, undergoing elective laparoscopic radical rectal cancer or radical prostate cancer surgery under general anesthesia, were divided into 2 groups ( n=37 each) by the random number table method: OLS group and non-OLS (NOLS) group. Patients in OLS group received small tidal volume ventilation, recruitment maneuvers, and individualized positive end-expiratory pressure. Fixed positive end-expiratory pressure 5 cmH 2O was given in NOLS group. Cerebral regional oxygen saturation (rSO 2), pH value, PaO 2, PaCO 2 and PaO 2/FiO 2 were recorded before induction of anesthesia (T 0, baseline value), at 10 min after tracheal intubation (T 1), at 1 and 2 h after pneumoperitoneum (T 2, 3) and at 10 min after extubation (T 4). The levels of serum interleukin-6 (IL-6), IL-10 and calcium-binding protein (S100β) were measured by enzyme-linked immunosorbent assay before surgery, at the end of surgery, and at 1 day after surgery. The development of POD was assessed using the delirium assessment scale at 1-3 days after surgery. Results:Compared with NOLS group, the pH value was significantly decreased at T 3, PaCO 2 was increased, PaO 2, PaO 2/FiO 2 and rSO 2 were increased at T 2-4, serum IL-6 and S100β concentrations were decreased after surgery and at 1 day after surgery, the serum IL-10 concentration was increased, and the incidence of POD was decreased in OLS group ( P<0.05). Conclusions:OLS can increase rSO 2, reduce the systemic inflammatory response, and decrease the risk of POD in elderly patients undergoing laparoscopic surgery.