Ultrasound of the stomach before operation to see it’s contents in the fasting patients scheduled for surgery
- Conditions
- Measurement and Monitoring,
- Registration Number
- CTRI/2020/03/024083
- Lead Sponsor
- Department of Anaesthesia and Intensive care
- Brief Summary
Pulmonary aspiration of gastric contents is a rare but, a serious complication of anaesthesia. Significant pulmonary complications happens in almost half of patients who aspirate and almost 50% of deaths in anaesthesia are directly due to aspiration of gastric contents, which occurs more commonly in patients with risk factors, at the time of induction of anaesthesia or during airway instrumentation. The presence of gastric contents increases the risk of aspiration and as a result practice guidelines for preoperative fasting have been designed to provide adequate time for gastric emptying in patients undergoing surgery.
The practice guidelines of American Society of Anesthesiologists (ASA) for healthy adults consider a minimum fasting duration of 2 hrs for clear fluids, 6 hrs for a light meal and 8 hrs for a fatty meal, fried foods or meat to be safe. However , uncertainty still exists regarding the exact gastric residual volume(GRV) that places the patients at increased risk of aspiration despite following standard fasting guidelines.
Many techniques have been described to assess the gastric contents like gastric content aspiration, paracetamol absorption, electrical impedance tomography, radio labelled diet, magnetic resonance imaging and the gold standard being gastric scintigraphy. Each modality has its pros and cons. Gastric ultrasound will be performed using a low frequency curvilinear array probe. With the advent of newer portable ultrasound (US) machines, it is possible to accurately assess the gastric contents non- invasively. Antrum It is the region of the stomach which is most amenable to ultrasonographic examination and also the portion which is most consistently identified (98- 100% cases) on ultrasonography (USG). Antral cross sectional area (CSA) calculated from gastric ultrasound highly correlates with scintigraphy and therefore cross sectional area of gastric antrum accurately predicts gastric fluid volume with the same precision as scinitgraphy. It thus helps the anaesthetist to anticipate the aspiration risk at bedside and guide anaesthetic and airway management more appropriately. Scanning was first done in the supine position followed by right lateral decubitus position. According to the appearance of the contents , qualitative assessment was done followed quantitative analysis. For the latter , antral cross sectional area (ACSA) was measured at the level of the aorta using ultrasound machine. All images were obtained between peristaltic contractions of the antrum. ACSA was measured in right lateral decubitus position using traditional two diameter method (TDM) . This involved measuring two perpendicular diameters of the antrum, from serosa to serosa, longitudinal or craniocaudal (CC), and the anteroposterior (AP) using the formula developed by Bolondi et al in which
ACSA = (CC × AP) × π) / 4, with π value = 3.14. Later, using ACSA , gastric volume was calculated using the formula,
Gastric volume (mL) = 27 + 14.6 ACSA (cm2) - 1.28 age (years) which is given by Perlas et al.
Hence, the present study was undertaken to ascertain the gastric residual volume (GRV) by point of care gastric ultrasound in fasting patients scheduled to undergo elective surgery and correlated the same with the hours of fasting and any underlying co-morbidities.
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- Completed
- Sex
- All
- Target Recruitment
- 400
- Adult patients of either sex aged between 18 to 80 years.
- American Society of Anaesthesiologists status I-II.
- Patients scheduled for elective surgery.
- Patients with history of prior gastric or lower esophageal surgery 2.
- Patients with known abnormalities of the upper gastrointestinal tract (such as hiatal hernias and gastric tumors) 3.
- Pregnancy 4.
- Patients unable to turn and lie in lateral position 5.
- Patients with BMI more than 35kg/m2 6.
- Patients who are not able to understand the study procedure and provide informed written consent.
Study & Design
- Study Type
- Observational
- Study Design
- Not specified
- Primary Outcome Measures
Name Time Method To use point of care gastric ultrasound for assessing the preoperative gastric residual volume in patients scheduled for elective surgery After 8 hours of fasting
- Secondary Outcome Measures
Name Time Method 1. To correlate the measured gastric volume with hours of fasting 2. To find correlation between the measured gastric volume with any underlying comorbidities
Trial Locations
- Locations (1)
Government medical college and hospital,Chandigarh
🇮🇳Chandigarh, CHANDIGARH, India
Government medical college and hospital,Chandigarh🇮🇳Chandigarh, CHANDIGARH, IndiaChaitra T SPrincipal investigator9482911971drchai94@gmail.com