Ultrasonography-Guided Nasogastric Tube Placement and Verification: A Standardized Nursing Protocol

Summary

Ultrasonography provides a safe, radiation-free, bedside method for real-time verification of nasogastric tubes. This evidence-based nursing protocol standardizes indications, acquisition, interpretation, and decision-making, supporting timely gastric access and demonstrating nurses’ capacity to achieve high diagnostic accuracy.

Abstract

This protocol presents a standardized, evidence-based nursing approach for ultrasonography-guided nasogastric tube (NGT) placement and verification in adult patients. The method was developed from a scoping review of 29 studies that examined clinical indications, technical procedures, and decision-making strategies for point-of-care ultrasonography (PoCUS) in NGT confirmation. Across the literature, ultrasonography consistently emerged as a safe, rapid, radiation-free tool for real-time visualization of the tube within the esophagus and stomach. While chest radiography remains the conventional reference standard, the cumulative evidence demonstrates that ultrasound reduces delays in confirming placement and initiating enteral nutrition—an outcome of particular relevance in critically ill or nutritionally vulnerable populations. The protocol describes key technical components, including optimal patient positioning, selection of cervical and epigastric sonographic windows, and the use of linear and convex transducers for accurate visualization. It also integrates direct and indirect verification techniques, such as hyperechoic tube identification and dynamic fogging. Overall, this protocol aims to enhance patient safety, standardize clinical practice, expand nursing autonomy, and support broader adoption of PoCUS for gastric access verification.

Introduction

Nasogastric tube (NGT) insertion is a high-frequency nursing procedure and remains one of the most common sources of preventable adverse events related to enteral therapy in adult patients^1,2. Misplacement of the tube into the respiratory tract or inadequate gastric positioning may result in serious complications, including pneumothorax, aspiration pneumonia, and delayed or unsafe initiation of enteral nutrition^1,2,3. For this reason, accurate and timely verification of tube position is a critical component of patient....

Protocol

This study was reviewed and approved by the Institutional Review Board of the Ribeirão Preto College of Nursing, University of São Paulo (CAAE No. 78296623.2.0000.5393). The Institutional Review Board approved the use of ultrasound image data for research purposes and waived the requirement for additional approval related to diagnostic imaging, as no CT scan data were used in this study. Informed consent was obtained from all individuals, and all images included in this work were acquired and used with the participants' explicit authorization.

1. Overview of the operational framework

1. Eligibility cr....

Results

In successful examinations, the cervical esophageal window allowed clear visualization of the NGT as a hyperechoic linear or double-line structure within the esophageal lumen, typically posterior and slightly lateral to the trachea (Supplemental Video S1). During real-time insertion, dynamic observation of tube advancement through the cervical esophagus confirmed correct esophageal passage and excluded airway misplacement.

At the epigastric window, correct gastric placement wa.......

Discussion

The present protocol provides a structured, reproducible approach to ultrasonography-guided NGT placement and verification, translating established sonographic principles into actionable steps for bedside practice. One of the most critical steps in the protocol is the systematic acquisition of both cervical and epigastric windows, as reliance on a single anatomical window may lead to false reassurance or incomplete assessment. Continuous real-time visualization during tube advancement, particularly at the cervical esopha.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Ultrasound system (portable or bedside)	VINNO Technology (Suzhou) Co., Ltd	8000166	System capable of abdominal and superficial imaging
Linear ultrasound probe (6–13 MHz)	VINNO Technology (Suzhou) Co., Ltd	8000166	Used for cervical window visualization
Curvilinear ultrasound probe (2–5 MHz)	VINNO Technology (Suzhou) Co., Ltd	N/A	Used for epigastric/gastric window
Nasogastric tube (adult)	Medicone	80020550040	Standard enteral feeding tube
20 mL syringe	General	N/A	Used for optional air flush maneuver
Ultrasound gel	General	N/A	Acoustic coupling for ultrasound examination
Medical gloves	General	3600714832	Standard infection control precautions
Lubricant gel	General	N/A	Facilitates nasogastric tube insertion
Adhesive tape or tube fixation device	General	N/A	Secures the tube after placement
Patient bed or examination stretcher	General	N/A	Patient positioned in semi-recumbent position