Effects Of Preoperative Carbohydrate Drink On Gastric Volume Before Anesthesia In Patients With Type 2 Diabetes

Objective Bedside ultrasound was used to evaluate the effects of different doses of carbohydrate drink on the gastric volume 2 hours before anesthesia in patients with type 2diabetesMethods1.Subjects:This study was a prospective,randomized,parallel controlled study.The study subjects were 80 patients with type 2 diabetes who underwent elective surgical treatment under general anesthesia in our hospital from August 2019 to February 2020.Patients were divided into four groups based on the different doses of carbohydrate consumption 2 hours before aesthesia:patients in group C did not drink carbohydrates;patients in group CH1 drank 100ml of carbohydrates;patients in group CH2 drank 200ml of carbohydrates,and patients in group CH3 drank 300ml of carbohydrates.Carbohydrate consumption 2 hoursbefore operation was recorded as T_0.The time of carbohydrate consumption was immediately recorded as T_l,while the time of anesthesia induction was recorded as T₂.2.Methods:（1）Gastric volume was assessed by bedside ultrasound:the gastric antrum diameter D1（cm）and the anteroposterior diameter D2（cm）were measured at time points of T₀,T_l and T₂.According to the formula of gastric antrum cross sectional area（CSA）=D1×D2×π/4,gastric volume,（GV）ml=27+14.6×CSA-1.28×age,Gastric antrum cross sectional area（CSA）,gastric volume（GV）and gastric volume per unit body weight（GV/W）were calculated among all patients at time points of T₀,T_l and T₂.（2）Assessment of reflux aspiration risk:the Perlas A scale was used to grade the gastric volume of the four groups at time points of T₀,T_l and T₂,and calculate the proportion of Perlas A of grade 2,and observe the proportion of GV/W>1.5ml/kg in each group.The risk of reflux aspiration was also assessed in the four groups（3）Blood glucose monitoring:capillary blood glucose was detected at T₀and T₂in each group of diabetic patients.Preoperative elevation of blood glucose>2mmol/L was defined asclinical significance.（4）Assessment of other complications:the incidence of nausea and vomiting 24 hours after operation was recorded.Results1.General informationThere were no statistically significant difference in age,gender composition,height,weight,Body mass index and ASA,Course of disease,fasting blood glucose,glycosylated hemoglobin（Hb A1c）,blood glucose control grading among the four groups（p>0.05）.2.Ultrasound evaluation of gastric volume in the four groups2.1 CSA assessment:at T_0,there was no statistically significant difference in CSA among the four groups（p>0.05）.At T₁,CSA in CH1 group,CH2 group and CH3 group were increased significantly compared with group C（12.63±1.94 vs 16.66±3.55 vs 23.22±2.22 vs 7.03±1.53,p<0.05）.At T₂,there was no statistically significant difference in CSA among the four groups（p>0.05）.At T₀ and T₂,there was no significant difference in CSA among the four groups（p>0.05）.2.2 GV assessment:at T₀,there was no statistically significant difference in GV among the four groups（p>0.05）.At T₁,the GV of CH1 group,CH2 group and CH3 group were increased significantly compared with that of C group（124.05±30.32 vs 196.31±52.48 vs 286.53±38.20vs 50.13±21.00,p<0.05）.At T₂,there was no significant difference in GV among the four groups（p>0.05）.At T₀and T₂,there was no significant difference in GV among the four groups（p>0.05）.2.3 GV/W assessment:at T₀,there was no statistically significant difference in GV/W among the four groups（p>0.05）.At time T₁,the GV/W of CH1 group,CH2 group and CH3 group were increased significantly compared with that of C group（1.96±0.61vs3.07±0.95vs4.28±0.83 vs 0.79±0.29,p<0.05）.At T₂,there was no statistically significant difference in GV/W among the four groups（p>0.05）.At T₀ and T₂,there was no significant difference in GV/W among the four groups（p>0.05）.3.Assessment of reflux aspiration risk in the four groups3.1 Assessment of grade 2 of perlas A:at T₁,the proportion of grade 2 of perlas A in group CH1,group CH2 and group CH3 was significantly higher than that in group C:（94.74%vs 95%vs 100%vs 10%,p<0.05）.Compared with T₀,there was no statistical difference in the proportion of perlas A of grade 2 in each group at T₂（p>0.05）.3.2 GV/W>1.5ml/kg assessment:at T₁,the proportion of GV/W>1.5ml/kg in the CH1 group,CH2 group and CH3 group was significantly higher than that in the C group:（84.21%vs 95%vs 100%vs 10%,p<0.05）.Compared with T₀,there was no statistically significant difference in ratio of GV/W>1.5ml/kg in each group at T₂（p>0.05）.4.Comparison of blood glucose fluctuation pre-operationThere was no significant difference in capillary blood glucose in group C at T₀ and T₂（p>0.05）.Compared with T₀,capillary blood glucose in CH1 group,CH2 group and CH3 group was increased at T₂:（7.00±0.96 vs 7.69±0.92,6.92±1.05 vs 8.68±1.52,6.66±1.28 vs 10.11±2.61,p<0.05）.At T₂,CH3 group blood sugar,C group increased significantly in the CH2 group:（10.11±2.61 vs 7.69 vs 7.69 vs 0.92±0.92,p<0.05）.The Elation of blood glucose in CH1 and CH2 group was less than 2 mmol/L,while CH3 group blood glucose increased more than 2mmol/L.This data indicated that no more than 200 ml carbohydrate drink 2 hours before anesthesia had no significant effect on blood glucose on patients with diabetes,but drinking300ml of carbohydrates could lead to an increase in blood sugar in patients with diabetes.5.Assessment of other complications There was no statistically significant difference in the incidence of nausea and vomiting 24hours after the operation among the four groups（p>0.05）.Conclusion1.In patients with type 2 diabetes,300ml carbohydrate drink 2 hours before anesthesia had no significant effect on gastric volume,and there was no increased risk of reflux aspiration and postoperative nausea and vomiting.2.In patients with type 2 diabetes,no more than 200ml of carbohydrate drink had no significant effect on blood glucose,while 300ml of carbohydrate drink could lead to an increase in blood glucose in patients with diabetes before anesthesia.