Pulmonary Aspiration Of Gastric Contents Research Articles

Association of NPO duration with glycemia in nondiabetic adolescents undergoing anesthesia for noncardiac surgery.

Children and adolescents are required to fast prior to undergoing anesthesia to minimize the risk of pulmonary aspiration of gastric contents. Pre-operative fasting times vary, with longer fasts (8 hours) for solid foods and shorter fasts for clear liquids (1-2hours). Pediatric patients are more sensitive than adults to pre-operative fasting secondary to smaller glycogen stores and resultant propensity to ketoacidosis.1 Prolonged pre-operative fasting is associated with suboptimal perioperative outcomes including insulin resistance, hypotension upon induction, patient thirst and malaise, and postoperative nausea and vomiting.2 While prior studies have shown that children younger than 36 months can present with low-normal blood glucose (BG) levels after prolonged pre-operative fasting, no correlation between nil per os (NPO) duration and BG has been found.1 We sought to study this phenomenon of glycemia in older children and adolescents, hypothesizing that with full hepatic maturity and increased glycogen reserves, absence of correlation between NPO duration and BG levels would be upheld.

A comparative study of bolus phenylephrine and mephentermine for treatment of hypotension during spinal anaesthesia for caesarean section

Background: Spinal anesthesia for caesarean section has several advantages over general anaesthesia like decreased risk of failed intubation, decreased risk of pulmonary aspiration of gastric contents, avoidance of the depressant effects of general anesthetics on neonate etc.Aim and Objectives: This comparative study was designed to evaluate the efficacy of Mephentermine and Phenylephrine in treating hypotension during spinal anaesthesia for cesarean section. The incidence of undesirable side effects like maternal bradycardia, nausea and vomiting also noted.Methodology: The study was conducted in the Department of OBG the Maternity Hospital, Osmania Medical College during the year August 2018- November 2019.The study includes 60 patients grouped into two groups.Results: Both Phenylephrine and Mephentermine maintained the arterial pressure effectively within 20% of baseline values. The mean value of heart rate was high in Mephentermine group compared with Phenylephrine group. The mean values of Systolic BP, Diastolic BP and MAP were higher in Phenylephrine group compared with Mephentermine group throughout the study period. Phenylephrine group required fewer number of bolus doses when compared with Mephentermine. The heart rate generally remained low throughout the study period in Phenylephrine group and the incidence of bradycardia was more in Phenylephrine group when compared with Mephentermine group. The occurrence of nausea and vomiting were similar in both groups.Conclusion: Thus, it can probably enhance organ blood flow more than mephentermine. Mephentermine increases heart rate and thus may be avoided in population where the effect may be detrimental.

Journal-related Activities and Other Special Activities at the 2020 American Society of Anesthesiologists Meeting.

Journal-related Activities and Other Special Activities at the 2020 American Society of Anesthesiologists Meeting.

Preoperative bedside ultrasound assessment of gastric volume and evaluation of predisposing factors for delayed gastric emptying: a case-control observational study.

Perioperative pulmonary aspiration of gastric content is a serious complication. Fasting guidelines try to ensure an empty stomach before intervention. Certain medications or pathologies may cause delayed gastric emptying. Bedside ultrasonography is a useful tool when gastric content status is unclear or in emergency situations where fasting is not feasible. The aim of this prospective case-control observational study was to assess differences in gastric fluid volume between fasted patients with or without predisposing factors for delayed gastric emptying. Patients were preoperatively scanned. Antral cross-sectional area was measured by two tracing methods and total gastric clear fluid volumes were calculated. Data was recorded from September 2018 to March 2019 in a university hospital setting in Barcelona, Spain. Fifty-three patients were enrolled, 23 with delayed gastric emptying predisposing factors (DGEF) and 30 without non-DGEF. Ultrasound-estimated gastric clear fluid volume was 35.21 ± 32.69mL in the DGEF versus 53.50 ± 30.72mL in the non-DGEF group (p = 0.08). Average volume per unit of weight was 0.61 ± 0.46mL/kg. Only 1 patient in the DGEF group had a volume that posed a higher risk of aspiration (1.57mL/kg). Perfect correlation (R = 0.91; p < 0.01) and concordance (0.91; 95% CI 0.83; 0.95) was found between tracing methods. Minimal gastric content was observed in scheduled surgery in spite of predisposing factors for delayed gastric emptying. Ultrasound clear gastric volume estimation was useful to assess preoperative bedside gastric content.

Incidence of post-operative nausea and vomiting and its associated factors following pediatric ophthalmic surgery at University of Gondar Comprehensive Specialized Hospital, 2019

BackgroundPostoperative nausea and vomiting is still viewed as minor problems, even though they are one of the major causes of morbidity in pediatric surgical patients like surgical site bleeding, pulmonary aspiration of gastric contents, fluid and electrolyte disturbances and dehydration, delayed hospital discharge, unexpected hospital admission and decreased patient satisfaction and cost. Surgical, anesthetic related factors as well as patient factors are major contributing factors for PONV. PurposeThe objective of this study was to assess Incidence of post-operative nausea and vomiting and factors associated with vomiting after pediatrics ophthalmic procedure under GA. Designprospective cross sectional study. MethodsInstitutional based prospective observational study was conducted to determine Incidence of post-operative nausea and vomiting and its associated factors. Data were checked on daily basis for completeness and were entered to Epi info and analyzed using statistical package for social sciences (SPSS) version 20 software. FindingsThe overall incidence of post-operative vomiting in pediatrics ophthalmic procedure under GA was 19.9% (CI = 14.5–25.3%). Factors associated with post-operative vomiting were age>3years, motion sickness and duration of surgery >30min. ConclusionThe incidence of post-operative vomiting after pediatrics ophthalmic procedure was 19.9%. Age>3years, motion sickness and duration of surgery >30 min were significantly associated with post-operative vomiting.

An international survey about rapid sequence intubation of 10,003 anaesthetists and 16 airway experts.

Pulmonary aspiration of gastric content is a significant cause of anaesthesia-related morbidity and mortality. High-quality prospective randomised evidence to support prevention strategies, such as rapid sequence intubation, is difficult to generate due to well-described practical, ethical and methodological barriers. We aimed to generate an understanding of worldwide practice through surveying clinically practicing anaesthetists and airway experts. Our survey was designed to assess the influence of: departmental standards; patient factors; socio-economic factors; training; and supervision. We surveyed 10,003 anaesthetists who responded to an invitation to participate on LinkedIn. We then surveyed 16 international airway experts on the same content. When asked about a hypothetical patient with intestinal obstruction, respondents expressed preferences for [OR (95%CI)]: the head-up or -down position 4.26 (3.98-4.55), p<0.001; nasogastric tube insertion 29.5 (26.9-32.3), p<0.001; and the use of cricoid force 2.80 (2.62-3.00), p<0.001, as compared with a hypothetical patient without intestinal obstruction also requiring rapid sequence intubation. Respondents from lower income countries were more likely to prefer [OR (95%CI]: the supine position 2.33 (2.00-2.63), p<0.001; nasogastric tube insertion 1.29 (1.09-1.51), p=0.002; and cricoid force application 2.54 (2.09-3.09), p<0.001 as compared with respondents from higher income countries for a hypothetical patient with intestinal obstruction. This survey, which we believe is the largest of its kind, demonstrates that preferences for positioning, nasogastric tube use and cricoid force application during rapid sequence intubation vary substantially. Achieving agreed consensus may yield better training in the principles of rapid sequence intubation.

Perioperative fasting: A review.

Preprocedural/preoperative fasting is a key part of preparing a patient for undergoing sedation or anaesthesia to minimise the risk of pulmonary aspiration of gastric contents. As part of caring for elective surgical patients it is important that healthcare staff in the perioperative environment have a good understanding of both the current guidelines and underpinning evidence so that they can effectively manage preoperative patients. This article looks to summarise the latest guidelines regarding perioperative fasting for adult and paediatric patients, the underlying evidence behind these guidelines and finally review current literature which will inform future practice. This article therefore looks to reinforce best practice, to ensure that the safety and comfort of patients in the perioperative period is optimised.

Gastric Ultrasound for the Regional Anesthesiologist and Pain Specialist

(Reg Anesth Pain Med. 2018;43:689–698) A significant cause of patient morbidity in the perioperative setting is pulmonary aspiration of gastric contents. Despite patients following the American Society of Anesthesiologists recommendations for fasting before a procedure, there is substantial variability in gastric-emptying time among patients. This may lead to a small percentage of patients that still have solid gastric contents at the time of operation. Gastric ultrasound has the potential to play an important role in the perioperative setting to provide reliable information regarding gastric content and assessment of aspiration risk.

Term Pregnant Patients have Similar Gastric Volume to Nonpregnant Females: A Single-Center Cohort Study

(Br J Anaesth. 2019;122(1):79–85. Doi: 10.1016/j.bja.2018.07.025) Current studies suggest that gastric emptying time is not prolonged in pregnancy. However, these data come from small samples. Pulmonary aspiration of gastric contents during obstetric anesthesia remains a concern. In the present study, authors assessed the range of gastric fluid volume in fasted nonlaboring term pregnant patients and fasted nonpregnant female patients scheduled for surgery.

The Clinical Use of Cricoid Pressure: First, Do No Harm.

Application of cricoid pressure (CP) during rapid sequence induction and intubation sequence has been a "standard" of care for many decades, despite limited scientific proof of its efficacy in preventing pulmonary aspiration of gastric contents. While some of the current rapid sequence induction and intubation guidelines recommend its use, other international guidelines do not, and many clinicians argue that there is insufficient evidence to either continue or abandon its use. Recently published articles and accompanying editorials have reignited the debate on the efficacy and safety of CP application and have generated multiple responses that pointed out the various (and significant) limitations of the available evidence. Thus, a critical discussion of available data must be undertaken before making a final clinical decision on such an important patient safety issue. In this review, the authors will take an objective look at the available scientific evidence about the effectiveness and safety of CP in patients at risk of pulmonary aspiration of gastric contents. We suggest that current data are inadequate to impose clinical guidelines on the use of CP because we acknowledge that currently there is not, and there may never be, a method to prevent aspiration in all patients. In addition, we reiterate that a universally accepted medical-legal standard for approaching the high-risk aspiration patient does not exist, discuss the differences in practice between the US and international practitioners regarding use of CP, and propose 5 recommendations on how future studies might be designed to obtain optimal scientific evidence about the effectiveness and safety of CP in patients at risk for pulmonary aspiration.

Ultrasound assessment of gastric antrum in term pregnant women before elective cesarean section

Background and objectivesPregnant women are considered patients at risk for pulmonary aspiration of gastric contents. The study aim was to evaluate the gastric antral cross-sectional area using ultrasound. MethodIn this prospective study, 85 scheduled term pregnant women underwent gastric ultrasound. The outcomes were the measurement of the gastric antral cross-sectional area (main outcome), the estimated gastric volume, the incidence of pregnant women at risk for pulmonary aspiration, and the association between gastric antral cross-sectional area and clinical-demographic characteristics. Gastric antral cross-sectional area and gastric volume were compared according to body mass index <30 or ≥30. ResultsThe median (IIQ) for gastric antral cross-sectional area was 4cm2 (2.8–6.3), for the estimated gastric volume it was 49.8mL (33.7–87.2), and for the gastric volume estimated in mL.kg−1 it was 0.62mL.kg−1 (0.39–0.95). The 95th percentile [95% confidence interval (CI)] of the gastric antral cross-sectional area and the estimated gastric volume were ≤10.3cm2 (95% CI: 7.6–15.6) and 1.42mL.kg−1 (95% CI: 1.20–2.64), respectively. The incidence of pregnant women at risk for pulmonary aspiration was 3.5% (CI: 3.5 (1.2–9.8)). There was a positive correlation between gastric antral cross-sectional area and weight, p<0.001 and body mass index <0.001. Patients with a body mass index ≥30 had a gastric antral cross-sectional area and an estimated gastric volume greater than those with a body mass index <30, respectively, p<0.01 and p<0.02. ConclusionMeasuring the gastric antral cross-sectional area of pregnant women is feasible and easy. There was positive correlation between gastric antral cross-sectional area, body weight and body mass index. The estimation of gastric volume by measuring the gastric antral cross-sectional area can identify patients at risk for pulmonary aspiration. Obese patients had a gastric antral cross-sectional area and an estimated gastric volume greater than non-obese patients.

Ultrassom de antro gástrico em gestantes a termo antes de cesariana eletiva

Background and objectivesPregnant women are considered patients at risk for pulmonary aspiration of gastric contents. The study aim was to evaluate the gastric antral cross‐sectional area using ultrasound. MethodIn this prospective study, 85 scheduled term pregnant women underwent gastric ultrasound. The outcomes were the measurement of the gastric antral cross‐sectional area (main outcome), the estimated gastric volume, the incidence of pregnant women at risk for pulmonary aspiration, and the association between gastric antral cross‐sectional area and clinical‐demographic characteristics. Gastric antral cross‐sectional area and gastric volume were compared according to body mass index <30 or ≥ 30. ResultsThe median (IIQ) for gastric antral cross‐sectional area was 4cm2 (2.8‐6.3), for the estimated gastric volume it was 49.8mL (33.7‐87.2), and for the gastric volume estimated in mL.kg−1 it was 0.62mL.kg−1 (0.39‐0.95). The 95th percentile [95% confidence interval (CI)] of the gastric antral cross‐sectional area and the estimated gastric volume were ≤ 10.3cm2 (95% CI: 7.6‐15.6) and 1.42mL.kg−1 (95% CI: 1.20‐2.64), respectively. The incidence of pregnant women at risk for pulmonary aspiration was 3.5% (CI: 3.5 (1.2‐9.8). There was a positive correlation between gastric antral cross‐sectional area and weight, p <0.001 and body mass index <0.001. Patients with a body mass index ≥ 30 had a gastric antral cross‐sectional area and an estimated gastric volume greater than those with a body mass index <30, respectively, p <0.01 and p <0.02. ConclusionMeasuring the gastric antral cross‐sectional area of pregnant women is feasible and easy. There was positive correlation between gastric antral cross‐sectional area, body weight and body mass index. The estimation of gastric volume by measuring the gastric antral cross‐sectional area can identify patients at risk for pulmonary aspiration. Obese patients had a gastric antral cross‐sectional area and an estimated gastric volume greater than non‐obese patients.

Operative fasting guidelines and postoperative feeding in paediatric anaesthesia-current concepts.

Preoperative fasting period is the prescribed time prior to any procedure done either under general anaesthesia, regional anaesthesia or sedation, when oral intake of liquids or solids are not allowed. This mandatory fasting is a safety precaution that helps to protect from pulmonary aspiration of gastric contents which may occur any time during anaesthesia. We searched PUBMED for English language articles using keywords including child, paediatric, anaesthesia, fasting, preoperative, gastric emptying. We also hand searched references from relevant review articles and major society guidelines. Association of Paediatric Anaesthesiologists of Great Britain and Ireland (APAGBI), the French Language Society of Paediatric Anaesthesiologists and the European Society of Paediatric Anesthetists recommends clear fluid intake upto one hour prior to elective surgery unless specific contraindications exists. Current guidelines recommend fasting duration of 4 hours for breastmilk, 6 hours for milk and light meals and 8 hours for fatty meals. The European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines recommend that oral intake can be initiated within hours of surgery in most patients. While fluids can be started almost immediately, the introduction of solids should be done more cautiously.

Ultrasound guided preoperative assessment of gastric antral cross-sectional area with respect to fasting hours to avoid the pulmonary aspiration of gastric contents

Ultrasound guided preoperative assessment of gastric antral cross-sectional area with respect to fasting hours to avoid the pulmonary aspiration of gastric contents

Diagnostic Accuracy of Point-of-Care Gastric Ultrasound.

Pulmonary aspiration of gastric contents is associated with significant perioperative morbidity and mortality. Previous studies have investigated the validity, reliability, and possible clinical impact of gastric ultrasound for the assessment of gastric content at the bedside. In the present study, we examined the accuracy (evaluated as sensitivity, specificity, and likelihood ratios) of point-of-care gastric ultrasound to detect a "full stomach" in a simulated scenario of clinical equipoise. After a minimum fasting period of 8 hours, 40 healthy volunteers were randomized in a 1:1 ratio to either remain fasted or ingest a standardized quantity of clear fluid or solid. Each subject was randomized twice on 2 independent study sessions at least 24 hours apart. A gastric ultrasound examination was performed by a blinded sonographer following a standardized scanning protocol. Using a combination of qualitative and quantitative findings, the result was summarized in a dichotomous manner as positive (any solid or >1.5 mL/kg of clear fluid) or negative (no solid and ≤1.5 mL/kg of clear fluid) for full stomach. Data from 80 study sessions were analyzed. In this simulated clinical scenario with a pretest probability of 50%, point-of-care gastric ultrasound had a sensitivity of 1.0 (95% confidence interval [CI], 0.925-1.0), a specificity of 0.975 (95% CI, 0.95-1.0), a positive likelihood ratio of 40.0 (95% CI, 10.33-∞), a negative likelihood ratio of 0 (95% CI, 0-0.072), a positive predictive value of 0.976 (95% CI, 0.878-1.0), and a negative predictive value of 1.0 (95% CI, 0.92-1.0). Our results suggest that bedside gastric ultrasound is highly sensitive and specific to detect or rule out a full stomach in clinical scenarios in which the presence of gastric content is uncertain.

Sonographic gastric content evaluation in patients undergoing cataract surgery.

Perioperative pulmonary aspiration of gastric contents is a serious complication and causes mortality and morbidity. The study aimed to assess the gastric content of patients undergoing cataract surgery by performing bedside ultrasonography. The secondary aim was to conduct a survey of hospital staff about fasting for cataract surgery. This single-center, cross-sectional study included 65 patients who underwent cataract surgery. The quantitative and qualitative measurements of the gastric content and antral area were performed by gastric ultrasonography in the right lateral decubitus position. The incidence of risk to the stomach was defined according to different threshold levels: content >0.8 ml/kg and 1.5 ml/kg and cross-sectional antral area >340 mm2. A questionnaire was provided to anesthesiologists and ophthalmologists about fasting for cataract surgery. The mean age was 69.48 ± 11.10 years. The mean gastric antrum cross-sectional area (CSA) was 11.08 ± 6.42 cm2. The predicted gastric volume was 103.39 ± 94.79 ml and 1.37 ± 1.20 ml/kg. The antral area CSA and gastric volume/kg decreased as the fasting time increased. About 98.5% of the patients exceeded the high-risk stomach antral cut-off CSA defined as 340 mm2. Gastric content exceeded 0.8 ml/kg in 58.33% of patients and exceeded 1.5 ml/kg in 41.67% of patients. Gastric content in patients was found to be 65.0% solid, 20.0% liquid, and 15.0% empty. All seven ophthalmologists did not apply fasting protocols for cataract surgery. Point of care ultrasonography is a useful, noninvasive tool in determining gastric content and volume. As majority of the patients presented with a full stomach for cataract surgery, we recommend that ophthalmologists and anesthesiologists follow preoperative fasting guidelines for cataract surgery.

Pulmonary aspiration of gastric content as a complication in prone position laryngeal mask insertion: A case report

Pulmonary aspiration of gastric content as a complication in prone position laryngeal mask insertion: A case report

HYPOGLYCAEMIA AS A CONSEQUENCE OF PRE-OPERATIVE FASTING: MYTH OR REALITY?

Background: The fatal risk of pulmonary aspiration of gastric contents during anaesthesia had since been recognized and consequently preoperative fasting guideline is usually prescribed to prevent this. Concern about development of hypoglycaemia during prolonged fasting has often been expressed, especially in children. AIM: This study is intended to determine the fasting blood glucose in preoperative patients of different age groups who were fasted for varying duration of time, and determine whether indeed hypoglycaemia occurs during inadvertently prolonged fasting which we often encounter in our practice setting. Methodology: A prospective cohort study of fasting blood glucose (FBG) of patients presenting for elective surgery in the principal investigator's operating rooms at the National Orthopaedic Hospital, Enugu, Nigeria was carried out. Blood glucose meter was used for estimation of glucose in capillary whole blood of the patients and the obtained data were analysed using SPSS version 16.0 statistical software. Comparison of mean values was done using the Chi-square test with statistical significance put at P &lt; 0.05. Results: Out of one hundred and thirty three patients studied with mean age of 30.2 ± 19.60 years (range: 1-72 years), and mean duration of fasting 12.73 ± 2.01 hours, (range: 8-16 hours), the mean fasting blood glucose was found to be 91.49 ± 13.36mg/dl (range: 58 - 124mg/dl). No relationship was found between age and FBG (Pearson's correlation coefficient, r = 0.025). Likewise duration of fasting did not relate with FBG (Pearson's correlation coefficient, r = 0.088). One patient (0.8%) had hypoglycaemia, with blood glucose of 58mg/dl. Conclusion: Hypoglycaemia as a consequence of pre-operative fasting is rare, even in non-infants fasted for considerably long hours. Neither patient's age, gender, nor duration of fasting had any significant influence on the fasting blood glucose of the patients.&#x0D; Keywords: Hypoglycaemia; Pre-operative fasting; Whole blood; Plasma.

Ultrasound assessment of the prevalence of increased gastric contents and volume in elective pediatric patients: A prospective cohort study.

Though pulmonary aspiration of gastric contents occurs mainly in the setting of emergency surgery, it may also occur in children scheduled for elective surgery without any obvious clinical risk factor. Increased gastric content volume is one the predisposing factors for pulmonary aspiration that could affect such children and may be identified using ultrasound examination of the gastric antrum. We aimed to assess the prevalence of "at-risk stomach" defined by ultrasound visualization of any solid content in the antrum and/or by calculated gastric fluid volume>1.25mL/kg, in children scheduled for elective surgery. Children scheduled for elective surgery were consecutively included into this prospective cohort study. Preoperative ultrasound examination of the antrum was performed in both the supine and the right lateral decubitus positions. Gastric fluid content was assessed using a 0-2 qualitative grading scale. The antral cross-sectional area was also measured in both the supine and the right lateral decubitus positions, allowing the calculation of the gastric fluid volume according to a formula previously described. We analyzed 200 elective children. Median duration of fasting was 4hours for liquids and >13hours for solids. None of the children included in this study had evidence of solid content. Six (3%) children had a Grade 2 antrum (fluid content seen in both the supine and the right lateral decubitus positions). Two children had a gastric fluid volume >1.25mL/kg. The prevalence of "at-risk stomach" was 1% (95% confidence interval: 0.2%-3.9%). According to our results, only 1% of elective children had potentially increased risk for pulmonary aspiration. Further studies should be performed in order to define the target population of elective children for which ultrasound assessment of gastric content should be performed prior to general anesthesia.

Dinâmica ultrassonográfica dos volumes do conteúdo gástrico após a ingestão de água de coco ou sanduíche de carne. Um estudo cruzado controlado e randômico com voluntários saudáveis

BackgroundAdequate preoperative fasting is critical in preventing pulmonary aspiration of gastric content. We proposed to study the sonographic gastric content dynamics after the ingestion of liquid or solid food in healthy volunteers and confront it with current guidelines for preoperative fasting times. MethodsWe performed a prospective, crossover, evaluator‐blinded study involving 17 healthy volunteers of both sexes. Each participant fasted for 10h and was subjected to a baseline gastric ultrasound, intake of 400mL of coconut water or a 145g, 355kcal meat sandwich, and sonographic gastric evaluations after 10min and every hour until the stomach was completely empty. ResultsAt baseline, all subjects had an empty stomach. At 10min, gastric content [mean + standard deviation (SD)] was 240.4 + 69.3 and 248.2 + 119.2mL for liquid and solid foods, respectively (p>0.05). Mean + SD gastric emptying times were 2.5 + 0.7 and 4.5 + 0.9h for liquid and solid foods, respectively (p<0.001). For the drink, the stomach was completely empty in 59% and 100% of the subjects after two and four hours, and for the sandwich, 65% and 100% of the subjects after four and seven hours, respectively. ConclusionsSonographic gastric dynamics for coconut water and a meat sandwich resulted in complete gastric emptying times higher and lower, respectively, than those suggested by current guidelines for preoperative fasting.