Point-of-Care Ultrasound to Assess Gastric Content in Pediatric Emergency Department Procedural Sedation Patients

Abstract

Objectives: There is debate regarding the timing of procedural sedation and analgesia (PSA) in relation to fasting status. Point-of-care ultrasound (POCUS) provides the ability to measure gastric content and is being used as a surrogate for aspiration risk in anesthesia. We sought to evaluate the gastric content of pediatric emergency department (PED) patients undergoing PSA using POCUS. Methods:We performed a prospective observational study using a convenience sample of pediatric patients undergoing PSA between July 1, 2018, and June 30, 2019. Following a brief history, gastric content was measured using POCUS in both supine and right lateral decubitus positions at 2-hour intervals until the time of PSA. Qualitative content and calculated volume were classified based on the Perlas Model of anesthesia "Risk" assessment.Results: Ninety-three patients were enrolled with 61.3% male and mean age of 6.5 years. Gastric content was determined in 92 patients. There were 79.3% that had "high risk" content at the time of PSA, with a median fasting time of 6.25 hours and no serious adverse events. Fasting duration had a weak to moderate ability to predict "risk" category (area under the curve = 0.73), with no patient (n = 17) who underwent multiple evaluations awaiting PSA progressing from "high" to "low risk." Conclusions:The majority of PED patients undergoing PSA at our institution had "high risk" gastric content with no clinically significant change occurring during serial evaluations. This calls into question the utility of delaying PSA based upon fasting status and lends support to a more comprehensive risk-benefit approach when planning pediatric PSA.

Gastric point-of-care ultrasound evaluation in pediatric emergency department procedural sedation patients; is the stomach empty at the point of scheduled revisit?

“…At the beginning of this study, there was no reference to guide sample size calculation to assess the presence of a sonographic empty stomach in PED patients with a scheduled revisit. We assumed an empty stomach ratio of 50% in patients presenting for a schedule revisit, based on prior studies of unscheduled PSA patients in the PED and nonelective pediatric surgery patients [19,20,22]. We calculated that enrollment of more than 93 patients from approximately 500 annual cases of PSA, would allow a 95% confidence interval for the proportion of empty stomach with a width of ±10%.…”

“…In our study, 82% of patients showed an empty stomach after a median NPO time of 7.5 hours for solid intake and 6 hours for clear liquid intake. This study included a population with lower age group, weight, and height but similar body mass index than in other studies [20][21][22]34]. The ROC analysis suggested the optimal cut-off of solid food NPO duration for gastric emptying was 6.5 hours when the patients had more than 2 hours of liquid fasting.…”

“…Leviter et al [21] reported that only 31% of patients had an empty stomach after 5.8 (4.6-7.7) hours of solid fasting and 5.2 (4.1-6.8) hours after liquid fasting. Moake et al [22] conducted a study on 93 patients with PSA, and reported that gastric emptying could be confirmed in only 20% of patients fasting more than 6 hours and in less than 40% of patients fasting for more than 8 hours. In our study, empty stomach was confirmed in 82% of patients fasting more than 6 hours and 87% of patients fasting of solid food more than 8 hours, which is higher than previous studies in the PED mentioned above.…”

“…The reason for fasting is to ensure gastric emptying, and it has been reported that patients undergoing unscheduled procedures have significantly delayed gastric emptying times, unlike patients undergoing elective surgery [20]. Recently, studies that confirmed "full stomach" using a gastric POCUS in children undergoing PSA in PED have been reported, and these studies found that the frequency of an empty stomach even after 6 hours of fasting as called for by the ASA recommendation is quite low [21,22]. We questioned whether delayed gastric emptying in the PED was similar in patients with a scheduled revisit.…”

SP41 Indicators that pocus is here to stay for anaesthesiologists too!

“…It allows to personalize aspiration risk assessment and to tailor anesthetic management to the individual patient. [10][11][12][13][14] Lung POCUS has proven to be a valuable tool for the detection of pneumothorax, pleural effusion, consolidation and alveolar interstitial syndrome in the critical care setting, searching for signs like: Lung sliding (sliding of visceral and parietal pleura over one another with respiration), that may rule out pneumothorax, A lines (repeated parallel lines below pleura), suggesting that there is no parenchymal disease and B lines ( vertical lines) indicating fluid in the lungs or an interstitial syndrome. According to studies it seems to have comparable or even higher sensitivity and specificity than the chest x ray in diagnosing common lung pathologies as alveolar interstitial syndrome, consolidation, pleural effusion and pneumothorax.…”