Objective To evaluate the value of ultrasonographic measurement of the antral crosssectional area (CSA) in assessing the preoperative gastric content volume in preschool pediatric patients.Methods Fifty American Society of Anesthesiologists physical status Ⅰ or Ⅱ pediatric patients of both sexes,aged ＜7 yr,undergoing elective non-gastrointestinal surgery,were fasted according to the preoperative fasting guidelines recommended by American Society of Anesthesiologists.Sedation was performed with intravenously injected midazolam or with intravenously injected midazolam and propofol after admission to the operating room.The antral CSA in the supine and right lateral decubitus positions was measured using bedside ultrasonography and free tracing method.A gastric tube was inserted after gastric sonography to collect the gastric fluid,and the total volume of the gastric fluid was considered to be the gastric content volume.Results Six pediatric patients were excluded due to the unsatisfactory ultrasound image,and 44 pediatric patients were included.Gastric content volume and gastric content volume per kilogram of body weight were positively correlated with the antral CSA in the right lateral decubitus position,and the Spearman correlation coefficients were 0.48 (P＜0.01) and 0.37 (P＜0.05),respectively.There was no correlation between gastric content volume and gastric content volume per kilogram of body weight and the antral CSA in the supine position (P＞0.05).Conclusion Ultrasonographic measurement of the antral CSA in the right lateral decubitus position can be used to assess the preoperative gastric content volume in preschool pediatric patients.

Objective To evaluate the accuracy of ultrasonographic measurement of the subglottic airway diameter in selecting the cuffed endotracheal tube (ETT) size for the pediatric patients with congenital heart disease.Methods Sixty pediatric patients of both sexes with congenital heart disease,of American Society of Anesthesiologists physical status Ⅱ-Ⅳ,aged 1 month-7 yr,undergoing elective open heart surgery,were included in this study.The subglottic airway diameter was measured by bedside ultrasonography after induction of anesthesia.The outer diameter of the cuffed ETT was determined according to the subglottic airway diameter.The air leak test was performed after intubation to determine whether or not the ETT size selected based on ultrasonography was appropriate.When the difference between the inner diameter of the finally selected ETT and the result calculated by the Motoyama formula was less than 0.2 mm,the ETT size selected based on the Motoyama formula was considered appropriate.The agreement and correlation between the subglottic airway diameter measured by age-based formula and ultrasonography and the outer diameter of the actually selected ETT were analyzed using Bland-Altman plot and Passing-Bablok regression analysis.Results The accurate rate of the ETT selected based on the ultrasonic measurement and Motoyama formula were 80％ and 55％,respectively,and there was significant difference (P＜0.05).Conclusion Ultrasonographic measurement of the subglottic airway diameter produces higher accuracy than the classical Motoyama formula in selecting the cuffed ETT size for the pediatric patients with congenital heart disease.

Objective To examine the effect of rapid infusion test guided by extravascular lung water index (EVLWI) on hemodynamics in critically ill patients at different states in order to guide volume resuscitation.Methods A prospective observation was conducted.Forty critically ill patients admitted to Department of Critical Care Medicine of Tianjin Third Central Hospital from June 2012 to April 2014 were enrolled.Based on the levels of EVLWI and pulmonary vascular permeability index (PVPI) and the cardiac function,the patients were divided into four groups:septic patients with normal EVLWI and PVPI (n =17),septic patients with increased EVLWI and PVPI (n =3),septic patients with increased EVLWI and normal PVPI (n =4),and coronary heart disease and heart failure patients with normal EVLWI and PVPI (n =16).The rapid infusion test was conducted in all patients using lactated Ringer solution 250 mL,followed by infusion of crystalloid with rate of 150 mL/h.The conditions of mechanical ventilation and vasoactive drugs were not changed during study.The changes in EVLWI,intrathoracic blood volume index (ITBVI),and cardiac index (CI) before capacity load,at immediate capacity load,and 15,45,105 minutes after load were determined by pulse indicator continuous cardiac output (PiCCO).On the base of volume status before and after the liquid infusion,the standard for the changes were:stroke volume (SV) increased by 12％-15％,central venous pressure (CVP) greater ≥ 2 mmHg (1 mmHg =0.133 kPa),CI ＞ 15％,and ITBVI change greater than 10％.Results There were no statistically significant differences in the observed indicators at the each time point before and after rapid infusion test among the four groups (all P ＞ 0.05).In septic patients with normal EVLWI and PVPI group,ITBVI was slightly increased by 5.4％-9.7％ from 15 minutes to 45 minutes after rapid infusion test.In coronary heart disease and heart failure patients with normal EVLWI and PVPI group,the EVLWI was increased by 11.9％,5.9％,and 14.7％ respectirely at 15,45,and 105 minutes,ITBVI was slightly increased by 6.4％ at 45 minutes,CI was increased by 29.5％ immediately after rapid infusion.In septic patients with increased EVLWI and PVPI group,CVP was increased by 8 mmHg immediately,EVLWI was increased significantly by 15.8％ at 45 minutes,ITBVI was slightly decreased by 10.0％ at 45 minutes,CI was increased by 24.7％ immediately,and increased by 17.0％ at 105 minutes,and PVPI was increased by 15.6％-28.1％ at 15-105 minutes after rapid infusion.In septic patients with increased EVLWI and normal PVPI group,CVP was increased by 1.5 mmHg at 15 minutes,EVLWI was increased immediately,which was increased by 17.4％,24.0％,and 31.4％ respectively at 15,45,and 105 minutes,ITBVI was increased by 13.9％ at 15 minutes,CI was increased by 16.1％ at 15 minutes after rapid fluid infusion.Conclusions Rapid fluid replacement in critically ill patients with crystalloid,regardless of whether the EVLWI was normal or increased,the short-term response was affected by the volume and cardiac function of patients.Different status of patients showed different volume effect curve:no significant changes in hemodynamic parameters were found in patients with normal EVLWI and volume parameters.In patients with potential cardiac dysfunction,CI and EVLWI increased significantly; regardless of PVPI increased or normal,EVLWI and CI were increased in patients with elevated EVLWI; two different changes could be found in the two types of pulmonary edema while ITBVI was increased.