Accurate verification of nasogastric tube (NGT) placement is critical to prevent serious complications
such as aspiration pneumonia. Conventional methods like pH testing and X-ray are limited by
inconsistent reliability and unnecessary radiation exposure. Point-of-care ultrasonography (POCUS) has
emerged as a promising, noninvasive, and real-time alternative for NGT placement confirmation. This
study evaluates the diagnostic accuracy of POCUS in a pilot phase and an evidence-based protocol for
application in the main study.
Objectives
The study aims to: (1) assess the diagnostic accuracy of POCUS compared to X-ray (reference standard),
(2) analyze time efficiency and cost savings in a pilot study, and (3) examine the roles of an evidencebased protocol in the main study.
Methodology
The study comprised two phases. Phase I was a prospective pilot study (n=67) using convenience
sampling, conducted across five community clusters. Investigators received standardized training to
ensure interrater reliability. Phase II will enroll 530 participants across six community centres and four
acute or rehabilitation hospitals, employing a validated protocol with standardized imaging techniques,
compliance audits, and adherence to STARD guidelines. Diagnostic accuracy was measured using
sensitivity, specificity, and interrater reliability. Time and cost comparisons between POCUS and X-ray
were analyzed using paired t-tests.
Results
The pilot study demonstrated 100% sensitivity and 93.55% specificity. The mean time lag between
POCUS and X-ray confirmation was 4.47 hours, with potential cost savings of HKD 270,310. Interrater
reliability was high (Cronbach's α = 0.875; ICC = 0.778–0.875, p < 0.001), and protocol adherence was
100% in pre-study audits.
Conclusion
POCUS is a clinically effective, time-efficient, and cost-saving method for NGT verification. The
evidence-based protocol, supported by robust methodology and high interrater reliability, ensures
consistency, reduces bias and lies in statistical rigor. Phase II will further validate these findings in a
larger cohort, reinforcing POCUS as a viable first-line tool for NGT placement verification.
