Ultrasonographic evaluation of gastric emptying after ingesting carbohydrate-rich drink in young children: A randomized crossover study

Potential indication of chemotherapy for hypodipsia and arginine vasopressin deficiency secondary to hypothalamic-pituitary Langerhans cell histiocytosis: a case report and literature review

Hypothalamic-pituitary Langerhans cell histiocytosis (HP-LCH) is often associated with arginine vasopressin deficiency (AVD). Patients with AVD caused by HP-LCH rarely develop an impaired osmotic threshold for thirst (OTT). Improvement in OTT among such patients has not been reported in the literature. To our knowledge, here we report the first case of AVD due to HP-LCH in which hypodipsia resolved during chemotherapy. A nine-year-old Japanese girl presented with polydipsia, polyuria, anorexia, and hypernatremia (149.8 mEq/L) and was diagnosed with AVD secondary to HP-LCH. Visual analog scale examination showed a reduced OTT following the water deprivation test. During chemotherapy for Langerhans cell histiocytosis (LCH), serum sodium concentrations became stable between 138.9 and 142.9 mEq/L under the replacement of desmopressin. Repeated visual analog scale examinations showed that she experienced a sense of thirst at a serum sodium concentration of 142.3-144.6 mEq/L, at which she did not experience any thirst prior to the initiation of chemotherapy. These data suggest that chemotherapy directly improved the OTT in our patient. Improved mechanical compression or infiltration of the hypothalamus related to OTT may lead to the recovery of the sense of thirst. This report highlights the potential role of chemotherapy for solitary HP-LCH in patients with hypodipsia and AVD.

The Effect of Oral Fluid Administration 1 Hour before Surgery on Preoperative Anxiety and Gastric Volume in Pediatric Patients

INTRODUCTION

Today, preoperative fasting guidelines have changed, allowing clear liquid intake up to 1 h before surgery. However, concerns remain regarding the risk of aspiration associated with clear liquid intake. This study aimed to investigate the impact of clear fluid given 1 h before surgery on child anxiety and gastric volumes.

METHODS

A prospective, randomized, controlled study included 90 patients aged 5-12 years. The patients were randomly allocated into three groups by a computer-generated randomization: group F (n = 30): standard fasting group, group W (n = 30): patients who received oral water at a dose of 5 mL/kg 1 h before surgery, group C (n = 30): patients who received oral carbohydrate fluid at a dose of 5 mL/kg 1 h before surgery. All patients were assessed using the modified Yale Preoperative Anxiety Scale (m-YPAS) before and 1 h after fluid administration. Antral cross-sectional area (CSA) was measured with ultrasonography after intubation, and gastric residual volume (GRV) was calculated. Hemodynamic data, blood sugar level, and parental satisfaction were also recorded.

RESULTS

The m-YPAS scores obtained after 1 h were significantly lower in group C than in the other groups (p < 0.001). Antral CSA and GRV values were lower in group C and group W than in the fasting group (p < 0.001). Parental satisfaction was highest in group C.

CONCLUSION

This study suggests that allowing a carbohydrate-rich clear liquid intake 1 h before surgery can significantly reduce preoperative anxiety in pediatric patients without increasing the risk of aspiration.

Preoperative clear fluids fasting times in children: retrospective analysis of actual times and complications after the implementation of 1-h clear fasting

BACKGROUND

Preoperative fasting before elective pediatric surgery is a matter of ongoing debate. The objectives of this study were to evaluate the compliance to a recently implemented preoperative fasting protocol (clear fluids until 1 hour from the induction of anesthesia), to identify predictors of prolonged preoperative fasting time, and to determine whether duration of preoperative fasting was associated with adverse outcomes.

METHODS

Retrospective single-center study in an operating theater of a tertiary pediatric hospital.

RESULTS

In a 6-month period, 1820 consecutive patients were analyzed. The data collected in the questionnaire reporting the time of last food, milk and/or liquid intake, and eventual reasons for nonadherence was analyzed. Median (interquartile range) preoperative fasting time was 186 (110-345) min. In 502 patients (27.6%), duration of preoperative fasting to clear fluid ranged from 60 to 119 min, whereas in 616 (34%) it was 120-240 min. The reasons for not respecting fasting time rules are mostly related to communication issues or unwillingness by the patients. A significant difference in fasting times was evident between infants and children older than 10 years (188, 105-290 vs. 198, 115-362; p = 0.02). Fasting times were significantly shorter in the inpatient group and in the first scheduled patients of the morning. Clear fluids fasting times were significantly longer in patients with hypovolemia complications than in those without, 373 (185-685) vs. 180 (110-330) min (p < 0.0001). Longer fasting times to clear fluids, younger age, and scheduled surgery time were independently associated with the odds of experiencing complications.

CONCLUSIONS

In this single pediatric center study, median clear fluids fasting time was three times higher (180 min) than those recommended by the preoperative fasting protocol. Compliance to the protocol was observed in approximately 1 out of 4 patients (27.6%). Longer fasting times were associated with an increased risk of complications, which might be due to dehydration and/or hypovolemia.

Ultrasound assessment of gastric residual volume in patients over 60 years of age undergoing gastroscopy under sedation: a prospective cohort study

BACKGROUND

We aimed to assess the accuracy of ultrasonographic measurement of the antral cross-sectional area (CSA) in the preprocedural evaluation of gastric contents and volume in fasted patients > 60 yr of age scheduled for gastroscopy under sedation.

METHODS

We included n = 81 patients > 60 yr of age and n = 79 younger controls scheduled to undergo elective gastroscopy in a prospective cohort study. A gastric ultrasound examination was performed to measure the antral CSA in both semisitting and right lateral decubitus (RLD) positions. Afterward, patients were graded using the Perlas qualitative grading scale. The actual gastric volume was endoscopically suctioned. Full stomach was defined as gastric volume > 1.5 mL·kg-1 and/or the presence of solid particles. We constructed receiver operating characteristic curves to determine the accuracy of ultrasonographic measurement of RLD CSA to detect a gastric volume > 1.5 mL·kg-1 and calculated the diagnostic test attributes of RLD CSA for the identification of a gastric volume > 1.5 mL·kg-1 RESULTS: The incidence of full stomach was 8/81 (9.8%) in patients > 60 yr of age and 1/79 (1.2%) in young patients (risk difference, 8.6%; 95% CI, 1.3 to 15.8; P = 0.03). The cut-off value of RLD CSA was 10.4 cm2 for the detection of gastric volume > 1.5 mL·kg-1 in patients > 60 yr of age, with a sensitivity of 75%, a specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 98.6%.

CONCLUSION

Patients > 60 yr of age scheduled for gastroscopy under sedation had a higher incidence of a full stomach detected with ultrasound compared with a younger cohort, which is potentially associated with a higher aspiration risk. We calculated a cut-off value of RLD CSA for detecting gastric volume in patients > 60 yr of age of approximately 10 cm2, which may help to quickly assess patients at risk of aspiration.

TRIAL REGISTRATION

www.chictr.org.cn (ChiCTR2100048994); registered 19 July 2021.

Preoperative ultrasound evaluation of gastric contents in children one hour after ingestion of clear liquid: An observational study

Background

Gastric ultrasound is an effective, non-invasive method to assess the nature and volume of gastric content in the pediatric population. Recently, the UK, European, and French Pediatric Anesthesia Societies recommend fast for clear fluids in children for 1 h. However, studies showing that 1 h of fasting is safe in the pediatric population are still scarce. This study aims to verify by ultrasound evaluation if 1 h of fasting for clear liquids is sufficient to have an empty stomach before anesthetic induction.

Methodology

Patients between 11 months and 16 years of age scheduled for elective outpatient surgery were included. A qualitative and quantitative ultrasound evaluation was performed by calculating the cross-sectional area (CSA) of the gastric antrum, 1 h after ingesting a volume of 3 mL/kg of a non-carbonated sports drink, before anesthetic induction.

Results

Fifty patients were included. The average CSA measured by ultrasound was 2.85 ± 1.64 cm2 with an average calculated total volume of 12.9 ± 11.06 mL. All patients had an empty stomach criterion (calculated volume ≤1.5 mL/kg) during the ultrasound evaluation, with an average of 0.40 ± 0.23 mL/kg. With the qualitative assessment of gastric volume, 19 patients (38%) were classified as grade 0, 31 patients (62%) as grade 1, and none as grade 2.

Conclusion

One hour of fasting after ingestion of 3 mL/kg of a non-carbonated sports drink is sufficient to meet ultrasound criteria for an empty stomach in a pediatric population undergoing elective outpatient surgery.

2023 American Society of Anesthesiologists Practice Guidelines for Preoperative Fasting: Carbohydrate-containing Clear Liquids with or without Protein, Chewing Gum, and Pediatric Fasting Duration-A Modular Update of the 2017 American Society of Anesthesiologists Practice Guidelines for Preoperative Fasting

These practice guidelines are a modular update of the "Practice guidelines for preoperative fasting and the use of pharmacologic agents to reduce the risk of pulmonary aspiration: Application to healthy patients undergoing elective procedures." The guidance focuses on topics not addressed in the previous guideline: ingestion of carbohydrate-containing clear liquids with or without protein, chewing gum, and pediatric fasting duration.

Gastric Point-of-Care Ultrasound in Acutely and Critically Ill Children (POCUS-ped): A Scoping Review

Introduction

Point-of-care ultrasound (POCUS) use is increasing in pediatric clinical settings. However, gastric POCUS is rarely used, despite its potential value in optimizing the diagnosis and management in several clinical scenarios (i.e., assessing gastric emptying and gastric volume/content, gastric foreign bodies, confirming nasogastric tube placement, and hypertrophic pyloric stenosis). This review aimed to assess how gastric POCUS may be used in acute and critically ill children.

Materials and Methods

An international expert group was established, composed of pediatricians, pediatric intensivists, anesthesiologists, radiologists, nurses, and a methodologist. A scoping review was conducted with an aim to describe the use of gastric POCUS in pediatrics in acute and critical care settings. A literature search was conducted in three databases, to identify studies published between 1998 and 2022. Abstracts and relevant full texts were screened for eligibility, and data were extracted, according to the JBI methodology (Johanna Briggs Institute).

Results

A total of 70 studies were included. Most studies (n = 47; 67%) were conducted to assess gastric emptying and gastric volume/contents. The studies assessed gastric volume, the impact of different feed types (breast milk, fortifiers, and thickeners) and feed administration modes on gastric emptying, and gastric volume/content prior to sedation or anesthesia or during surgery. Other studies described the use of gastric POCUS in foreign body ingestion (n = 6), nasogastric tube placement (n = 5), hypertrophic pyloric stenosis (n = 8), and gastric insufflation during mechanical ventilatory support (n = 4). POCUS was performed by neonatologists, anesthesiologists, emergency department physicians, and surgeons. Their learning curve was rapid, and the accuracy was high when compared to that of the ultrasound performed by radiologists (RADUS) or other gold standards (e.g., endoscopy, radiography, and MRI). No study conducted in critically ill children was found apart from that in neonatal intensive care in preterms.

Discussion

Gastric POCUS appears useful and reliable in a variety of pediatric clinical settings. It may help optimize induction in emergency sedation/anesthesia, diagnose foreign bodies and hypertrophic pyloric stenosis, and assist in confirming nasogastric tube placement, avoiding delays in obtaining confirmatory examinations (RADUS, x-rays, etc.) and reducing radiation exposure. It may be useful in pediatric intensive care but requires further investigation.

Effect of pre-operative oral paracetamol on gastric residual volume and pH in young children in the context of a 1-hour clear fluid fast: a randomised controlled trial

High gastric residual volume and low pH are associated with increased mortality following pulmonary aspiration in animal studies. The use of pre-operative oral paracetamol has not been investigated in younger children and infants in the context of a prescriptive 1-h clear fluid fast aimed at reducing the risk of pulmonary aspiration while improving patient experience. Children aged 1 month up to a weight of 25 kg and scheduled for elective surgery were randomly allocated to receive a prescribed 3.6 ml.kg^-1 drink of water alone (water group) or 3 ml.kg^-1 water and oral Infant Calpol® syrup (24 mg.ml^-1 concentration, equivalent volume 0.6 ml.kg^-1 , paracetamol group) 1 h before the induction of anaesthesia. Following induction, a nasogastric tube was used to aspirate gastric contents and the volume and pH were recorded. Ninety-seven children, median (IQR [range]) age 24 (12-45 [1-96]) months and weight 12.4 (9.7-16.0 [2.9-27.0]) kg, were analysed. Median time from drink to induction was 54 (45-60 [21-113]) min. There was no significant difference in gastric residual volume (p = 1) or pH (p = 0.99) between the water and the paracetamol groups. Sub-group analysis revealed no significant difference in gastric residual volume or pH for 29 children who weighed < 10 kg compared with > 10 kg. Using a prescriptive fluid regime of 3 ml.kg^-1 of water, the addition of oral paracetamol syrup did not significantly alter gastric residual volume or pH in the context of a 1-h fast in infants and young children.

Pre-operative fasting in children: A guideline from the European Society of Anaesthesiology and Intensive Care

Current paediatric anaesthetic fasting guidelines have recommended conservative fasting regimes for many years and have not altered much in the last decades. Recent publications have employed more liberal fasting regimes with no evidence of increased aspiration or regurgitation rates. In this first solely paediatric European Society of Anaesthesiology and Intensive Care (ESAIC) pre-operative fasting guideline, we aim to present aggregated and evidence-based summary recommendations to assist clinicians, healthcare providers, patients and parents. We identified six main topics for the literature search: studies comparing liberal with conservative regimens; impact of food composition; impact of comorbidity; the use of gastric ultrasound as a clinical tool; validation of gastric ultrasound for gastric content and gastric emptying studies; and early postoperative feeding. The literature search was performed by a professional librarian in collaboration with the ESAIC task force. Recommendations for reducing clear fluid fasting to 1 h, reducing breast milk fasting to 3 h, and allowing early postoperative feeding were the main results, with GRADE 1C or 1B evidence. The available evidence suggests that gastric ultrasound may be useful for clinical decision-making, and that allowing a 'light breakfast' may be well tolerated if the intake is well controlled. More research is needed in these areas as well as evaluation of how specific patient or treatment-related factors influence gastric emptying.

Gastric emptying time of two different quantities of clear fluids in children: A double-blinded randomized controlled study

BACKGROUND

Perioperative pulmonary aspiration risk increases with increased preoperative gastric volume; hence traditionally, healthy children are kept fasted overnight before surgery. Current guidelines recommend 2-h clear fluids fasting prior to anesthesia. However, emerging evidence favors allowing 3 ml/kg clear fluids up to 1-h before anesthesia. We compared the gastric volume and gastric emptying time after ingestion of 3 ml/kg and 5 ml/kg of clear fluids.

METHODS

The present study enrolled 44 children, aged between 6 and 14 years. On the day of surgery, baseline gastric volume was estimated using ultrasound and patients were randomly allocated into two groups of equal number, that is, Group 3 and Group 5 (patients received 3 ml/kg and 5 ml/kg 5% Dextrose respectively). Repeated gastric ultrasound was performed at every 5 min until the gastric volume reached baseline levels. The primary objective of the study was to compare gastric emptying time. Secondary objectives included comparison of antral cross-sectional area and gastric volume.

RESULTS

The demographic profile, preoperative fasting duration for clear fluids, and baseline gastric volume were comparable between groups. In both groups, compared to baseline the antral cross-sectional area and gastric volume increased significantly following fluid ingestion and then decreased exponentially to reach baseline within 1-h. The median (IQR) (range) gastric emptying time (minutes) [35.0 (28.8, 40.0) (20.0-45.0) in group 3 and 40.0 (28.8, 45.0) (20.0-50.0) in group 5] and emptying half-time (minutes) [17.0 (15.7, 21.5) (14.4-24.0) in group 3 and 18.6 (16.0, 22.0) (15.1-23.8) in group 5] were comparable [median difference -5 (95% CI -7.8 to 2.1) and -1.5 (95% CI -2.3 to 1.0), respectively] (p = .16 and p = .44, respectively).

CONCLUSION

As the gastric volume returned to baseline within 1-h even after ingesting 5 ml/kg clear fluids, the preoperative fasting time can be reduced to 1-h and healthy children undergoing elective procedure can be safely allowed to drink up to 5 ml/kg clear fluids.

Pro-Con Debate: 1- vs 2-Hour Fast for Clear Liquids Before Anesthesia in Children

Perioperative fasting guidelines are designed to minimize the risk of pulmonary aspiration of gastrointestinal contents. The current recommendations from the American Society of Anesthesiologists (ASA) and the European Society of Anaesthesiology and Intensive Care (ESAIC) are for a minimum 2-hour fast after ingestion of clear liquids before general anesthesia, regional anesthesia, or procedural sedation and analgesia. Nonetheless, in children, fasting guidelines also have consequences as regards to child and parent satisfaction, hemodynamic stability, the ability to achieve vascular access, and perioperative energy balance. Despite the fact that current guidelines recommend a relatively short fasting time for clear fluids of 2 hours, the actual duration of fasting time can be significantly longer. This may be the result of deficiencies in communication regarding the duration of the ongoing fasting interval as the schedule changes in a busy operating room as well as to poor parent and patient adherence to the 2-hour guidelines. Prolonged fasting can result in children arriving in the operating room for an elective procedure being thirsty, hungry, and generally in an uncomfortable state. Furthermore, prolonged fasting may adversely affect hemodynamic stability and can result in parental dissatisfaction with the perioperative experience. In this PRO and CON presentation, the authors debate the premise that reducing the nominal minimum fasting time from 2 hours to 1 hour can reduce the incidence of prolonged fasting and provide significant benefits to children, with no increased risks.

Ultrasound assessment of gastric emptying time after intake of clear fluids in children scheduled for general anesthesia-A prospective observational study

BACKGROUND

While many clinics have changed their local regimen toward a more liberal policy regarding clear fluid fasting for general anesthesia, there is a lack of studies evaluating gastric emptying time in a clinical setting.

AIMS

Based on this and before implementation of a more liberal preoperative clear fluid fasting policy for children, we studied gastric emptying time of clear fluids in children and hypothesized that the mean gastric emptying time would be 1 hour.

METHODS

Between March and December 2019, children scheduled for general anesthesia at our University Children's Hospital were enrolled in this prospective observational study. After overnight fasting, gastric emptying was examined by sonographic measurements of the gastric antral area before and 5, 15, 30, 45, and 60 minutes after intake of water or fruit juice.

RESULTS

Twenty-six children were enrolled in this study, and 24 aged 11 (range 4-17) years were included for statistical analysis. The median ingested fluid volume was 4.7 (range 1.8-11.8) mL kg^-1 . The gastric antral area of the children initially increased and subsequently decreased after intake of clear fluids and correlated significantly with fasting time (r = -0.55, P < .0001). After 1 hour, the gastric antral area had returned to the baseline level in 20 children but not in four children with a fluid intake >5 mL kg^-1 . There was no difference in the gastric antral area between water and fruit juice. Using a linear regression model, the calculated mean gastric emptying time of clear fluids was 52 minutes.

CONCLUSION

This study showed that the gastric emptying time of children after intake up to 5 mL kg^-1 clear fluids was <1 hour in a clinical setting. These results support the more liberal fasting regimen favoring a 1-hour fasting time and suggest 5 mL kg^-1 as an upper limit for clear fluids (eg, water, sugared water or tea or diluted fruit juice) from 2 hours to 1 hour before induction of anesthesia in children.