The Effect Of Permissibility Hypercapnia On Postoperative Delirium In Elderly Patients Undergoing Thoracoscopic Surgery

Objective With the development of endoscopic technology,more and more elderly patients with esophageal cancer choose to undergo thoracoscopic radical resection of esophageal cancer.Postoperative delirium is a common complication of postoperativenervous system in elderly patients,which will affect the prognosis of patients and increase the medical burden.Previous studies have indicated that hypercapnia can improve cerebral oxygen and play a neuroprotective role.This study aims to explore the influence of permistable hypercapnia(PHY)on postoperative delirium(POD)in elderly patients undergoing thoracoscopic radical resection of esophageal cancer,so as to provide reference for perioperative management of elderly patients undergoing radical resection of esophageal cancer,so as to reduce the occurrence of postoperative delirium in such patients.Methods Ninety-two elderly patients(≥65 years old)who underwent thoracoscopic radical resection of esophageal cancer in cardiothoracic surgery department of our hospital were selected according to the exclusion criteria.The patients were divided into a group of 46 patients in the normal range of arterial partial blood carbon dioxide pressure [p(CO2)controlled in the range of 35 to 45 mm Hg](group N)and a group of46 patients in the mild PHY group [p(CO2)controlled in the range of 46 to 55 mm Hg](group H)by random number table method.Preoperative general information,such as age,gender,body mass index,ASA grading and MMSE score,was recorded in the 2groups.At awake(T0),intubation(T1),pneumothorax for 0.5 h(T2),pneumothorax for1 h(T3),and air release for 10 minutes(T4),p(CO2),mean arterial pressure(MAP),heart rate(HR),cerebral oxygen saturation(r SO2),airway Peak pressure(Peak),dynamic lung compliance(Cdyn),arterial blood gas value were recorded in 2 groups;Intraoperative infusion volume,urine volume,blood loss and ephedrine dosage were recorded in the 2 groups.Visual analog scale(VAS)was recorded and POD was assessed by Diagnostic delirium scale(CAM)for consecutive three days after surgery.Results Compared with T0,MAP,HR and rSO2 in group N and group H were decreased from T1 to T4(P < 0.05).Compared with group N,MAP and r SO2 in group H were higher at T2 ~ T4(P < 0.05).r SO2 was positively correlated with p(CO2)at T2~ T4(r = 0.438,0.646,0.554,P < 0.05).Compared with T0,PH and OI of patients ingroup N and group H decreased at T1-T4 and T2-T4(P < 0.05);Peak of patients in group N and group H increased at T2-T4 and Cdyn decreased at T2-T4(P < 0.05);Compared with group N,the PH of group H was lower at T2-T4(P < 0.05),the OI was higher at T2-T4(P < 0.05),the Peak was lower at T2-T3,and the Cdyn was higher at T2-T3(P < 0.05).There were no significant differences in intraoperative fluid volume,urine volume,and blood loss between the two groups(P > 0.05).Compared with group N,ephedrine dosage in group H was lower [(5.8±3.2)mg vs.(4.0±2.5)mg,t=3.014,P < 0.05].The VAS scores of patients in 2 groups were gradually decreased three days after surgery(P < 0.05),and there was no significant difference in VAS scores three days after surgery between 2 groups(P > 0.05).Compared with N group,POD incidence in H group was lower than that in N group(8.7%vs23.9%,χ2=3.903,P <0.05).Conclusion In elderly patients undergoing thoracoscopic radical resection of esophageal cancer,PHY ventilation strategy is helpful to stabilize intraoperative hemodynamics and improve organ tissue perfusion.It can reduce airway pressure while ensuring oxygenation,improve lung compliance,improve respiratory parameters to reduce lung injury;It can optimize the balance of oxygen supply and demand,increase r SO2 and reduce the incidence of POD.