Gastric Ultrasound for Airway Management in Emergency Patients

Airway Management Selection Based on Gastric Content and Residual Volume Assessment in Emergency Patients at RSCM: An Ultrasonography Study

This prospective observational cohort study evaluates the association between gastric residual content and volume, assessed by point-of-care gastric ultrasound (PoCUS), and the choice of airway management technique (Rapid Sequence Intubation vs. non Rapid Sequence Intubation) in adult emergency surgical patients at Rumah Sakit Cipto Mangunkusumo (RSCM). Aspiration risk in emergency patients is a critical concern, and this study examines whether objective ultrasonographic findings change clinical decision-making compared to traditional clinical assessment alone.

Study Overview

• Status: Completed
• Conditions: Airway Management; Gastric Residual Volume; Emergency Surgery; Pulmonary Aspiration of Gastric Contents
• Intervention / Treatment: Device: Preoperative Gastric Point-of-Care Ultrasound (PoCUS)

Detailed Description

Emergency patients frequently have delayed gastric emptying, increasing aspiration risk during airway management. Gastric PoCUS allows non-invasive, bedside assessment of gastric content (empty, liquid, solid, or mixed) and volume. This study quantifies gastric antrum cross-sectional area (CSA) using the Perlas formula (GV = 27.0 + 14.6 × CSA - 1.28 × age) and reports whether USG findings influenced the anesthesiologist's plan (RSI or non-RSI).

• Study Type: Observational
• Enrollment (Actual): 43

Contacts and Locations

Study Locations

• Indonesia
  • Jakarta Special Capital Region
    • Jakarta, Jakarta Special Capital Region, Indonesia, 01430
      • RSUPN Cipto Mangunkusumo

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Adult emergency surgical patients (age >18 years) requiring airway management under general anesthesia at the Emergency Operating Room of RSUPN Dr. Cipto Mangunkusumo (RSCM), Jakarta, Indonesia. The population includes both trauma (62.8%) and non-trauma (37.2%) emergency cases. Patients were enrolled consecutively from July to August 2025. Patients with conditions that could confound gastric ultrasound assessment or airway management decisions were excluded.

Description

Inclusion Criteria:

• Emergency patients requiring airway management in the Emergency Operating Room
• Age >18 years

Exclusion Criteria:

• Pregnancy
• Morbid obesity (BMI >40 kg/m²)
• History of prior gastric or esophageal surgery
• Duodenal tube in situ
• Maxillofacial trauma or anticipated difficult airway
• Inability to adequately visualize the gastric antrum on ultrasound

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

Emergency Surgical Patients; Adult emergency surgical patients (age >18 years) requiring airway management at the Emergency Operating Room of RSUPN Dr. Cipto Mangunkusumo (RSCM), who underwent preoperative gastric point-of-care ultrasound (PoCUS) to assess gastric content type and residual volume prior to anesthetic induction.

Device: Preoperative Gastric Point-of-Care Ultrasound (PoCUS); Gastric antrum ultrasound performed using a low-frequency transducer (2-5 MHz; SonoSite M-Turbo or Lumify Philips) in the supine position before anesthetic induction. The antrum cross-sectional area (CSA) was measured during the relaxation phase between two peristaltic contractions, calculating cranio-caudal (CC) and antero-posterior (AP) diameters. Gastric residual volume (GRV) was calculated using the Perlas formula: GV = 27.0 + 14.6 × CSA - 1.28 × age (years). Gastric content was classified as empty, liquid, solid, or mixed. Aspiration risk was categorized as high (GRV ≥1.5 ml/kg or solid content) or low (GRV <1.5 ml/kg or empty).; Other Names: Gastric Ultrasound; Gastric USG; Bedside Gastric Sonography

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Association between aspiration risk based on gastric ultrasound findings and airway management technique selection	Proportion of patients in whom airway management technique (Rapid Sequence Intubation vs. non Rapid Sequence Intubation) was associated with aspiration risk category (high vs. low) determined by preoperative gastric Point-of-Care Ultrasound (PoCUS) findings. Aspiration risk classified as high if Gastric Residual Volume (GRV) ≥1.5 ml/kg or solid gastric content; low if GRV <1.5 ml/kg or empty stomach. Analyzed using chi-square test.	At time of pre-induction assessment (single time point, intraoperative)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Airway Management Plan After Gastric USG	Comparison of airway management plan (RSI vs. non-RSI) before and after disclosure of gastric USG findings to the treating anesthesiologist. Analyzed using McNemar's paired categorical test.	Before and immediately after gastric USG, prior to anesthetic induction
Gastric Residual Volume	Gastric residual volume calculated using the Perlas formula: GV = 27.0 + 14.6 × CSA - 1.28 × age (years), based on antrum cross-sectional area (CSA) measured from cranio-caudal (CC) and antero-posterior (AP) diameters. Reported as mean ± SD or median (range).	At pre-induction assessment
Gastric Content Type	Proportion of patients with each gastric content category: empty, liquid only, solid, or mixed (solid and liquid), as identified by gastric PoCUS.	At pre-induction assessment
Fasting Duration and Its Relationship to Gastric Residual Volume	Fasting duration categorized as <8 hours, 8-12 hours, or >12 hours since last solid food intake, and its relationship to gastric residual volume and aspiration risk classification on USG.	At pre-induction assessment
American Society of Anesthesiologists (ASA) Physical Status Classification as a factor in airway management decision	Proportion of patients in each American Society of Anesthesiologists (ASA) class (I, II, III, IV) and its association with airway management technique selection (RSI vs. non-RSI) after gastric USG, analyzed using chi-square test.	At pre-induction assessment
Trauma Severity Score (ISS) as a factor in airway management decision	Injury Severity Score (ISS) categorized as severe (ISS ≥15) or mild-moderate (ISS <15) and its association with airway management technique selection (RSI vs. non-RSI) after gastric USG, analyzed using chi-square test.	At pre-induction assessment
Glasgow Coma Scale (GCS) score as a factor in airway management decision	GCS score recorded at pre-induction assessment and its association with airway management technique selection (RSI vs. non-RSI) after gastric USG.	At pre-induction assessment
Presence of clinical risk factors (sepsis, shock, GERD/gastritis) as a factor in airway management decision	Proportion of patients with each clinical risk factor (sepsis, hemorrhagic shock, GERD/gastritis) and its association with airway management technique selection (RSI vs. non-RSI) after gastric USG, analyzed using chi-square or Fisher's exact test.	At pre-induction assessment

Collaborators and Investigators

• Sponsor: Indonesia University

Study record dates

Study Major Dates

• Study Start (Actual): June 5, 2025
• Primary Completion (Actual): August 13, 2025
• Study Completion (Actual): September 13, 2025

Study Registration Dates

• First Submitted: June 2, 2026
• First Submitted That Met QC Criteria: June 8, 2026
• First Posted (Actual): June 10, 2026

Study Record Updates

• Last Update Posted (Actual): June 10, 2026
• Last Update Submitted That Met QC Criteria: June 8, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: emergency; airway management; gastric ultrasound; aspiration risk; rapid sequence induction (RSI); point-of-care ultrasound (PoCUS)
• Additional Relevant MeSH Terms: Pathologic Processes; Disease Attributes; Respiratory Tract Diseases; Digestive System Diseases; Gastrointestinal Diseases; Respiration Disorders; Esophageal Diseases; Esophageal Motility Disorders; Deglutition Disorders; Laryngopharyngeal Reflux; Gastroesophageal Reflux; Respiratory Aspiration; Pathological Conditions, Signs and Symptoms; Emergencies; Respiratory Aspiration of Gastric Contents
• Other Study ID Numbers: GastricUSG

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No