Preoperative Gastric Emptying And Its Influencing Factors In Patients Undergoing Emergency Surgery

Objective:To observe the nature and volume of gastric contents in emergency surgery patients by means of gastric antral ultrasound,to understand the incidence of satiety,and to evaluate the risk of satiety and aspiration in emergency surgery patients.Methods:227 patients with emergency surgery were included from February to October 2018.Exclusion criteria were as follows:age<18 years,patients with brain injury and coma,patients with active gastric ulcer and upper gastrointestinal hemorrhage,patients with previous esophageal and gastric surgery,and patients with pregnancy of more than 15 weeks.Patients who are unable to complete the ultrasound position,patients who refuse to undergo ultrasound examination.The patient was admitted to the operating room for gastric ultrasound examination.The patient was placed in two positions,supine position first,the head of bed was raised to 45°,and then in right lateral position.The probe was placed in the midline sagittal view of upper abdomen to observe the antrum,and the contents and properties of the antrum in two positions were observed.No further observations were made for those with definite solid food in the antrum,but further quantitative and semi-quantitative determinations were made for those with liquid food.Quantitative observation:In the right lateral decubitus position,images of the antrum were obtained,and the cranial-caudal diameter(AP)and anterior-posterior diameter(CC)of the antrum were marked and measured,and further converted into the cross-sectional area of the antrum,the volume of the stomach and the weight ratio of the volume of the stomach.Semi-quantitative observation was made under the above two positions,and the scores were divided into three grades(grade o,grade 1 and grade 2)and grade 0 stomach.No gastric contents were found in gastric antrum scan under both positions;Grade 1 stomach,no contents in gastric antrum under supine position,gastric fluid can be seen in right lateral decubitus position,indicating low gastric fluid volume;Grade 2 gastric fluid was observed in both the supine and right lateral decubitus positions,suggesting a high-risk stomach.Definition of empty stomach:Quantitatively observe whether the gastric contents are liquid and the volume-to-body weight ratio of stomach is ?1.5ml/kg;Definition of full stomach:The contents of the stomach are solid,or the contents of the stomach are liquid and the volume-to-weight ratio of the stomach is>1.5 ml/kg.The following patient information will also be collected:(1)basic parameters(gender,age,height,weight and body mass index,ASA classification),(2)co-morbidities(e.g.,diabetes mellitus,hypothyroidism,renal failure),(3)patient type of surgery,(4)fasting and drinking time,(5)anesthesia disposal,6)Complications of perioperative reflux aspiration.The relationship between quantitative and semi-quantitative observation methods was compared,and the correlation factors of satiety were analyzed.Results:Among 227 patients undergoing emergency surgery,21 cases(9.3%)did not obtain satisfactory ultrasound images of gastric antrum,27 cases(11.9%)did not cooperate with right lateral decubitus because of acute pain after trauma,and 179 cases(32.4%)were included in statistics.Of these,9(5%)had solid gastric contents,49(27.4%)had liquid gastric contents and a volume-to-body weight ratio>1.5 ml kg-1,and 121(67.6%)had empty stomach.Semi-quantitative grading results showed that 62 patients(34.6%)had grade 0 antrum,57 patients(31.8%)had grade 1 antrum,and 51 patients(28.5%)had grade 2 antrum.The analysis of general data of patients showed that the proportion of patients with diabetes mellitus was significantly higher in patients with satiety than in those with empty stomach(P<0.05),but there was no statistical difference in gender,age,height,BMI,fasting time,drinking time,department distribution,ASA grade,chronic kidney disease and hypothyroidism.The results of semi-quantitative grading criteria and quantitative measurement showed that the cross-sectional area of gastric antrum,gastric volume and volume weight increased with the increase of gastric antrum grade,and the difference was statistically significant.There were significant differences in the percentage of patients with gastric volume-to-body weight ratio>1.5ml/kg in different gastric antrum grading groups.Diabetes mellitus was the influence factor of gastric satiety before operation(P<0.05),while fasting time was not related to gastric satiety in patients undergoing emergency surgery.One of all patients with satiety had reflux out of gastric contents after intubation,and none of all patients with satiety had aspiration complications.Conclusion:The results of this study showed that gastric ultrasound can qualitatively and quantitatively observe the gastric contents of gastric antrum in more than 90%of patients who completed emergency surgery before operation.The proportion of patients with gastric satiety before emergency surgery was up to 32.3%.Diabetes was associated with gastric satiety.whereas fasting time was not associated with gastric satiety in patients undergoing emergency surgery.