Objective To discuss the feasibility of preoperative diet by measuring gastric emptying time of carbohydrate and protein nutrient solutions in healthy volunteers.Methods A total of 20 healthy volunteers were collected from August 2013 to May 2014.On the morning of the trial,baseline gastric residual volume of each volunteer was measured with magnetic resonance imaging at 8 a.m.,then each of the 20 healthy volunteers took 12.5％ carbohydrate solution 400 ml (containing 40 g of maltodextrin and 10 g of sucrose) or 12.5％ whey protein solution (containing 50 g whey protein) in 5 minutes.Magnetic resonance imaging was conducted to measure the gastric residual volume every 25 minutes.The volunteers were shifted to the other nutrient solution after a 1-week interval.The gastric emptying time of both nutrient solutions was calculated to generate the curves illustrating the process of gastric emptying.Results The baseline gastric residual volume of the volunteers was (14.90 ± 9.39) ml.The total gastric emptying time of carbohydrate solution was (104.90 ± 27.98) min (95 ％ CI 98.64-111.16 min),while that of whey protein solution was (199.6 ± 34.17) min (95％ CI 184.47-214.73 min).There was a significant difference between these two types of nutrient solution in terms of gastric emptying time (P ＜ 0.000 1).Conclusions The induction of anesthesia could be performed 2 hours after carbohydrate administration,and at least 4 hours after whey protein administration.

Objective To determine the gastric emptying time for liquids in the healthy volunteers by magnetic resonance imaging (MRI) and to provide a reference for reasonable preoperative fasting time.Methods Nineteen healthy volunteers of both sexes,of ASA physical status Ⅰ or Ⅱ,aged 20-60 yr,were enrolled in the study.The volunteers were fasted from the intake of liquids or solids starting from 22:00 the night before the trial,and 12.5％ carbohydrate solution 400 ml containing 40 g maltodextrin and 10 g sucrose was given orally.MRI was performed to measure the baseline gastric fluid volume at 8:00 on the day of the trial (T0).The gastric fluid volume was measured immediately after administration of the oral solution,and then measured every 25 min until the gastric fluid volume was returned to the baseline before administration of the oral solution or to ＜25 ml,and was recorded as T25,T50,T75,T100,et al.The gastric fluid volume was drawn using a computer to obtain the curve for gastric emptying.The gastric half and total emptying time was calculated using the curves.Results The gastric half emptying time was (32± 12) min,and the gastric total emptying time was (99±22) min in the volunteers.Compared with those at Tb,the gastric fluid volume was significantly increased at T25,T50,T75,T100,and no significant change was found in gastric fluid volume at T125,T150and T175.Conclusion After oral intake of liquids,the gastric emptying time is about 2 h,indicating that the preoperative fasting time for liquids can be shortened to 2 h before anesthesia in the healthy volunteers.

Objective To investigate the incidence of postoperative intubation-related complications and the need for measurement and adjustment of cuff-pressure of endotracheal tube. Methods Five hundred and nine patients of either sex undergoing elective surgery under general anesthesia with tracheal intubation were divided into 2 groups: control group (group C)and cuff-pressure measured group (group CPM). Operation time and duration of endotracheal tube were recorded. Twenty patients with the duration of endotracheal tube 120-180 min in each group were selected. Their tracheal mucous membrane was examined by fiberoptic bronchoscopy at the time of withdrawal of endotracheal tube. Postoperative complications including cough and bloody sputum were also recorded at 24 h after extubation. Results The two groups were comparable with respect to age, sex, operation time and the duration of endotracheal tube. The incidence of sore throat and bloody sputum was significantly higher in group C than in CPM group. The incidence of sore throat and bloody sputum was significantly increased as the duration of endotracheal tube was prolonged in control group while in CPM group only the incidence of sore throat was increased. Varying degrees of injuries to tracheal mucous membrane were observed with fiberoptic bronchoscope.The injuries were more serious in group C than in CPM group. Conclusion Measurement of intracuff pressure is helpful for reducing the tracheal intubation-related complications.

Objective:To evaluated the safety and feasibility of dissection of lymph nodes posterior to right recurrent laryngeal nerve (ⅥB compartment) in endoscopic thyroidectomy through gasless axillary posterior approach.Methods:A total of 350 cases with right lobe papillary thyroid carcinoma (PTC) who underwent endoscopic lobectomy, isthmusectomy and central compartment neck dissection via gasless axillary posterior approach based at the Department of General Surgery, Nanfang Hospital, Southern Medical University from June 2020 to December 2022 were retrospectively analyzed. Summarize the clinical, pathological characteristics, and postoperative complications of the patients. SPSS 25.0 was used for statistical analysis of the data.Results:All 350 patients underwent endoscopic surgery successfully, with no conversion to open surgery. There were 303 females and 47 males, with an average age of (36.3±9.2) years. Of those, 287 patients were in pT1a stage, 62 in pT1b stage, and one patient in pT2 stage. There was no T3 or T4 stage patient. The mean numbers of yielded lymph nodes in right central compartment and ⅥB compartment were 8.11±4.65 (range, 1-31) and 2.62±1.86 (range, 1-12), respectively. ⅥB compartment metastasis was detected in 52 (14.86%) of 350 patients. The incidence of transient recurrent laryngeal nerve injury was 0.86%(3/350). Postoperative hematoma occurred in three patients (0.86%).Conclusion:The dissection of ⅥB compartment in endoscopic thyroidectomy through gasless axillary posterior approach is safe and feasible in selected PTC patients

Objective To analyze coating properties of porous artificial joints,including coating morphology and coating mechanical properties,and summarize the range of coating properties of current mainstream products,to provide references for the design and development of new products,as well as provide the basis for the long-term implant removal analysis.Methods Samples for the surface morphology,shear strength,and tensile strength of the coatings used in the experiment were prepared in accordance with ASTM F1854,ASTM F1044,and ASTM F1 147 standards,respectively.The coatings were processed using plasma spraying.The surface morphology(coating thickness,porosity,and pore intercept)of the coatings for all 17 products(Nos.1-17)was tested;for products Nos.1-7 and Nos.15-16,the shear strength test between the coating and substrate was conducted first in accordance with the test method of ASTM F1044.Then,according to the test method of ASTM F1 147,the tensile strength test between the coating and substrate was conducted.For product No.17,the shear and tensile strengths of the composite coating and simple titanium coating were tested,respectively,according to the test method of ASTM F1044 and ASTM F1 147.Results A total of 15 products(88.2％)had coating thicknesses between 300 μm and 500 μm.There were 16 metal-coated products(Nos.1-16),of which 11(68.75％of the total)had coating porosities between 30％and 50％,and 14(87.5％of the total)had coating pore intercepts between 50 μm and 150 μm.The mechanical properties of the coatings were independent of the substrate material used.The shear and tensile strengths of the composite coatings with hydroxyaptite(HA)were significantly lower than those of the pure metal coatings.Conclusions For the design and manufacture of artificial joints with porous coatings,the performance of the coating can be referred to the following indexes:the coating thickness is 300-500 μm,the coating porosity is 30％-50％,the coating pore intercept is 50-150 μm.The substrate materials can be selected based on the use of the product.The effects of a lower bonding force on product performance should be considered when designing prostheses with composite coatings containing HA.This range of performance metrics provides control for long-term clinical extraction analyses.

Objective: To assess the safety and curative effect of gasless endoscopic selective lateral neck dissection (GESLND) via an anterior chest approach for papillary thyroid carcinoma (PTC). Methods: Eighteen patients with PTC(T1-2N1bM0, size<3.0 cm), having GESLND via an anterior chest approach, were included from November 2008 to December 2016. Results: GESLND via an anterior chest approach was successfully performed in all 18 PTC patients (seven male and eleven female) with 83.3% of T1 and 16.7% of T2. The mean operative time of selective lateral neck dissection was 73 min (range 51-92 min). The mean of intraoperative bleeding was 61.1 ml (range 30-120 ml). No major complications occurred except one transient hypoparathyroidism. No residual thyroid glands were detected on ultrasonography and thyroglobulin was(0.73±0.16)ng/ml three months postoperatively. The median of follow-up was 54.5 months (range 6-104 months). No recurrence disease was observed in any patient on ultrasonography, computer tomography, thyroglobulin or selective iodine-131 scan during the follow-up period. The cosmetic result and functional preservation was excellent, when the assessments were performed three months postoperatively. Conclusion GESLND via an anterior chest approach is feasible and safe for selected PTCs, with superior appearance.