Comparison Of Gastroesophageal Reflux In Different Positions During Induction Of General Anesthesia In Patients With Fast-track Surgery

Objective:To compare the horizontal position and the position of raising the head of the bed 30 degrees in colorectal surgery patients with fast-track surgery during the induction of general anesthesia,and to investigate whether the induction of general anesthesia at the head of the bed end up 30 degrees position can reduce the probability of gastroesophageal reflux.Methods:150 patients with colorectal surgery under general anesthesia under the perioperative treatment mode of fast-track surgery were selected.The patients were aged 35⁸0 years old,with body mass index（BMI）of 18²8 kg/m2,mouth opening greater than 3.5cm and ASA classification I^III.They were randomly divided into two groups:one group of patients with horizontal position carries on the induction of general anesthesia intubation（group A）,another group of patients carry on the induction of general anesthesia intubation by raising the head of the bed 30 degrees（group B）,two groups of patients were treated according to the perioperative period of fast-track surgery in our hospital brfore surgery,not for gastrointestinal decompression and drinking 400ml of clear carbohydrates 2 hours before surgery.UE visual laryngoscope was used for endotracheal intubation uniformly.PH test paper was used to measure the patients’esophageal entrance PH before anesthesia induction（T0）,after anesthesia induction（T1）,and after endotracheal intubation（T2）with the assistance of tracheal intubation forceps,and gastroesophageal reflux was determined in patients with PH≦4.Arterial blood gas analysis was performed in both groups at T1 time and 30min（T3）after the completion of intubation.Good record of two groups of patients with gender,age,height,weight,ASA classification,mouth opening,thyromental distance,successful intubation time,operative site and different time points in patients with heart rate（HR）,mean arterial pressure（MAP）,PH level,oxygen partial pressure（PO₂）and carbon dioxide partial pressure（PCO₂）in blood gas at T0 time and T3 time point..Results:1.There was no significant difference between the two groups in gender,ASA classification,age,height,weight,operative site and other general conditions（P>0.05）.2.There were no statistically significant differences between the two groups in the thyromental distance,degree of opening of the mouth,and the time of successful intubation（P>0.05）.3.There was no significant difference in heart rate and mean arterial pressure between the two groups at the time of T0 and T2（p>0.05）.At the time of T1,there was no statistical difference between the two groups（p>0.05）,compared with group A,the mean arterial pressure of group B was lower than that of group A,the difference was statistically significant（p<0.05）.4.There was no reflux in the two groups at the time of T0.At T1 time,12 patients had reflux in group A and 4patients had reflux in group B.The rates of reflux in the two groups were statistically significant（p<0.05）.At the time of T0 and T3,There was no significant difference in oxygen partial pressure and carbon dioxide partial pressure between the two groups（p>0.05）.Conclusion:The general anesthesia was induced by raising the head of the bed 30 degrees position can reduce the probability of gastroesophageal reflux in patients with fast-track surgery,however,it does not increase the time and difficulty of endotracheal intubation,and has little effect on the circulation in the two groups of patients.There was no significant difference in heart rate,oxygen partial pressure and carbon dioxide partial pressure between the two groups.