Effect Of CO₂ Pneumoperitoneum On Body Temperature In Patients Undergoing Laparoscopic Radical Gastrectomy For Gastric Cancer

Objective:By observing the changes of core body temperature in patients undergoing laparoscopic radical gastrectomy using different CO₂pressures and CO₂temperatures to establish pneumoperitoneum,the incidence of intraoperative hypothermia was analyzed in depth to provide a basis for selecting appropriate pneumoperitoneum for maintaining body temperature during surgery.Methods:According to the inclusion and exclusion criteria,108 patients who underwent laparoscopic radical gastrectomy for gastric cancer in the gastrointestinal surgery department of a tertiary hospital in Chengde City from October 2021 to July 2022 were collected as the subjects of this study.According to the principle of minimum distribution of imbalance index,the patients were divided into groups,and the gender and age of patients undergoing laparoscopic radical gastrectomy were the main control factors.After grouping according to the distribution method with the smallest imbalance index,the patients were divided into three groups:A（12 mm Hg,normal temperature）,B（14 mm Hg,normal temperature）and C（12 mm Hg,heating）,with 36 cases in each group.After the beginning of the operation,the same group of gastrointestinal surgeons used the abdominal 5-hole operation method for laparoscopic surgery.During the operation,the pneumoperitoneum machine（manufacturer:STORZ Endoscopy Company,Germany,model:26430520）was used to establish artificial pneumoperitoneum.The pneumoperitoneum pressure of group A was set to 12 mm Hg,group B was14 mm Hg,and group C was 12 mm Hg.After the establishment of pneumoperitoneum,the CO₂gas flow rate was controlled at 20L/min until the set pneumoperitoneum pressure was reached.After entering the room,the patients took the same thermal insulation measures,including maintaining the same indoor temperature and humidity,using the same body position during the operation,covering the same number of layers of operating sheets,and using 37℃warm saline and warm disinfectant during the operation.On this basis,three groups of patients used different gas temperatures to establish pneumoperitoneum:group A and group B used conventional pneumoperitoneum,and the temperature of pneumoperitoneum was 21℃;Group C used the heating device of the pneumoperitoneum machine to warm the CO₂gas to 37℃and then inject it into the patient’s abdominal cavity.During the operation,the ear thermometer was used to measure the temperature changes of the left ear of the patients in the three groups at the time of entering the room,endotracheal intubation,the beginning of the operation,10 minutes,30 minutes,60 minutes,90 minutes after the establishment of the pneumoperitoneum,30 minutes after the midway stop of the pneumoperitoneum,the re-establishment of the pneumoperitoneum,and the end of the operation,and at the same time,the pneumoperitoneum pressure（mm Hg）,flow rate（L/min）,and the temperature of the pneumoperitoneum（normal temperature,warming）were recorded.Through t test,analysis of variance Chi-square test was used to compare the changes of body temperature and the occurrence of hypothermia during the operation.Results:1 Effect of different CO₂pneumoperitoneum pressure on body temperature of patients undergoing laparoscopic radical gastrectomyLaparoscopic radical gastrectomy using 12～14mm Hg pressure to establish pneumoperitoneum can be carried out smoothly.1.1 Comparison of core body temperature between the two groups at different time points during operationThere was no hypothermia and no significant difference in core temperature between the two groups at the time of admission,endotracheal intubation and the beginning of surgery（P<0.05）.At 8 time points,10minutes after the establishment of pneumoperitoneum,30 minutes after the establishment of pneumoperitoneum,60 minutes after the establishment of pneumoperitoneum,90 minutes after the establishment of pneumoperitoneum,30 minutes after the cessation of pneumoperitoneum,30 minutes after the reconstruction of pneumoperitoneum,and the end of surgery,the core temperature of Group B was significantly lower than that of Group A,the difference was statistically significant（P<0.05）.1.2 Comparison of the incidence of intraoperative hypothermia between the two groups of patients1.2.1 Comparison of the incidence of hypothermia at the time of admission,endotracheal intubation and the beginning of surgery between the two groupsNo hypothermia occurred in the two groups at the time of admission,tracheal intubation and the beginning of operation,and the incidence of hypothermia was 0.1.2.2 The incidence of hypothermia was compared between the two groups at 10 min after the establishment of pneumoperitoneum.Among the 36 patients in group A,4 cases had hypothermia during operation,accounting for 11.11%.Among the 36 patients in group B,17 had hypothermia during operation,accounting for 47.22%;there was significant difference in the incidence of hypothermia between the two groups（P<0.05）.1.2.3 Comparison of the incidence of hypothermia 30 minutes after the establishment of pneumoperitoneum between the two groupsAmong the 36 patients in group A,19 cases had hypothermia during operation,accounting for 52.78%.Among the 36 patients in group B,33 had hypothermia during operation,accounting for 91.67%;there was significant difference in the incidence of hypothermia between the two groups（P<0.05）.1.2.4 Comparison of the incidence of hypothermia 60 minutes after the establishment of pneumoperitoneum between the two groupsAmong the 36 patients in group A,19 cases had hypothermia during operation,accounting for 52.78%.Among the 36 patients in group B,33 had hypothermia during operation,accounting for 91.67%;there was significant difference in the incidence of hypothermia between the two groups（P<0.05）.1.2.5 Comparison of the incidence of hypothermia 90 minutes after the establishment of pneumoperitoneum between the two groupsAmong the 36 patients in group A,16 cases had hypothermia during operation,accounting for 44.44%.Among the 31 patients in group B,32 had hypothermia during operation,accounting for 86.11%;there was significant difference in the incidence of hypothermia between the two groups（P<0.05）.1.2.6 Comparison of the incidence of hypothermia in the two groups when pneumoperitoneum stoppedAmong the 36 patients in group A,14 cases had hypothermia during operation,accounting for 38.89%.Among the 36 patients in group B,32 had hypothermia during operation,accounting for 88.89%;there was significant difference in the incidence of hypothermia between the two groups（P<0.05）.1.2.7 Comparison of the incidence of hypothermia 30 minutes after the cessation of pneumoperitoneum between the two groupsAmong the 36 patients in group A,7 cases of hypothermia occurred during the operation,accounting for 19.44%;hypothermia occurred in 29 of36 patients in group B,accounting for 80.56%.There was significant difference in the incidence of hypothermia between the two groups（P<0.05）.1.2.8 Comparison of the incidence of hypothermia during reconstruction of pneumoperitoneum between the two groupsAmong the 36 patients in group A,4 cases had hypothermia during operation,accounting for 11.11%.Hypothermia occurred in 29 of 36patients in group B,accounting for 80.56%.There was significant difference in the incidence of hypothermia between the two groups（P<0.05）.1.2.9 Comparison of the incidence of hypothermia at the end of surgery between the two groupsAmong the 36 patients in group A,14 cases had hypothermia during operation,accounting for 38.89%.Hypothermia occurred in 33 of 36patients in group B,accounting for 91.67%.There was significant difference in the incidence of hypothermia between the two groups（P<0.05）.2 Effects of different CO₂pneumoperitoneum temperatures on body temperature in patients undergoing laparoscopic radical gastrectomyLaparoscopic radical gastrectomy for gastric cancer can be successfully performedout smoothly by using normal temperature or heated CO₂gas to establish pneumoperitoneum.2.1 Comparison of core temperature between two groups of patients at different time points during operationThere was no significant difference in core body temperature between group A and group C at the time of admission,endotracheal intubation,operation start,30 minutes after pneumoperitoneum stop and reconstruction of pneumoperitoneum（P<0.05）.At 6 time points,10 minutes after the establishment of pneumoperitoneum,30 minutes after the establishment of pneumoperitoneum,60 minutes after the establishment of pneumoperitoneum,90 minutes after the establishment of pneumoperitoneum,at the end of pneumoperitoneum,and at the end of surgery,the core temperature of Group A was significantly lower than that of Group C,the difference was statistically significant（P<0.05）.2.2 Comparison of the incidence of intraoperative hypothermia between the two groups2.2.1 Comparison of the incidence of hypothermia at the time of admission,endotracheal intubation and the beginning of surgery between the two groupsNo hypothermia occurred at the time of admission,endotracheal intubation and the beginning of surgery in the two groups,and the incidence of hypothermia was 0.2.2.2 Comparison of the incidence of hypothermia 10 minutes after the establishment of pneumoperitoneum between the two groupsAmong the 36 patients in group A,4 had hypothermia during operation,accounting for 11.11%;no intraoperative hypothermia occurred in 36patients in group C,and the incidence was 0.There was significant difference in the incidence of hypothermia between the two groups（P<0.05）.2.2.3 Comparison of the incidence of hypothermia 30 minutes after the establishment of pneumoperitoneum between the two groupsAmong the 36 patients in group A,19 had hypothermia during operation,accounting for 52.78%;no intraoperative hypothermia occurred in 36 patients in group C,and the incidence was 0.There was significant difference in the incidence of hypothermia between the two groups（P<0.05）.2.2.4 Comparison of the incidence of hypothermia 60 minutes after the establishment of pneumoperitoneum between the two groupsAmong the 36 patients in group A,19 had hypothermia during operation,accounting for 52.78%;no intraoperative hypothermia occurred in 36 patients in group C,and the incidence was 0.There was significant difference in the incidence of hypothermia between the two groups（P<0.05）.2.2.5 Comparison of the incidence of hypothermia 90 minutes after the establishment of pneumoperitoneum between the two groupsAmong the 36 patients in group A,16 had hypothermia during operation,accounting for 44.44%;no intraoperative hypothermia occurred in 36 patients in group C,and the incidence was 0.There was significant difference in the incidence of hypothermia between the two groups（P<0.05）.2.2.6 Comparison of the incidence of hypothermia in the two groups when pneumoperitoneum stoppedAmong the 36 patients in group A,14 had hypothermia during operation,accounting for 38.89%;no intraoperative hypothermia occurred in 36 patients in group C,and the incidence was 0.There was significant difference in the incidence of hypothermia between the two groups（P<0.05）.2.2.7 Comparison of the incidence of hypothermia 30 minutes after the cessation of pneumoperitoneum between the two groupsAmong the 36 patients in group A,7 had hypothermia during operation,accounting for 19.44%;no intraoperative hypothermia occurred in 36patients in group C,and the incidence was 0.There was significant difference in the incidence of hypothermia between the two groups（P<0.05）.2.2.8 Comparison of the incidence of hypothermia during reconstruction of pneumoperitoneum between the two groupsAmong the 36 patients in group A,4 had hypothermia during operation,accounting for 11.11%;no intraoperative hypothermia occurred in 36patients in group C,and the incidence was 0.There was significant difference in the incidence of hypothermia between the two groups（P<0.05）.2.2.9 Comparison of the incidence of hypothermia at the end of surgery between the two groupsAmong the 36 patients in group A,14 had hypothermia during operation,accounting for 38.89%;no intraoperative hypothermia occurred in 36 patients in group C,and the incidence was 0.There was significant difference in the incidence of hypothermia between the two groups（P<0.05）.Conclusion:1 In laparoscopic radical gastrectomy for gastric cancer,the use of lower pressure CO₂pneumoperitoneum is beneficial to slow down the speed and amplitude of body temperature decline at the initial stage of surgery and reduce the incidence of intraoperative hypothermia.2 In laparoscopic radical gastrectomy for gastric cancer,the use of conventional CO₂gas to establish pneumoperitoneum will lead to a gradual decrease in the core body temperature of the patient and increase the incidence of hypothermia,while the use of heated CO₂gas to establish pneumoperitoneum can effectively avoid intraoperative temperature drop and reduce the occurrence of hypothermia.