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Point of Care Ultrasound for Diagnosis of Abdominal Free Air

Utility of Bedside Ultrasound for Diagnosis of Intraperitoneal Free Air

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT03719872
Enrollment
100
Registered
2018-10-25
Start date
2018-11-01
Completion date
2019-10-01
Last updated
2019-11-06

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Free Air in Abdomen

Keywords

laparoscopic surgery, transabdominal ultrasound, Free air

Brief summary

This study evaluates the ability of ultrasound to identify intraperitoneal free air. The study will consist of blinded review of abdominal ultrasound images of patients before and after laparoscopic surgery, a procedure which results in the introduction of air into the peritoneal cavity.

Detailed description

Free peritoneal air is a marker of potential intraabdominal catastrophe, reflecting perforation of a hollow viscous organ such as stomach or intestine. While definitively identified by computed tomography, this diagnostic test can be delayed. Presence of air beneath the diaphragm on an upright chest or abdominal radiograph can allow for faster diagnosis, but again can present limitations in terms of timing. Bedside clinician performed ultrasound has become standard practice in emergency medicine and critical care settings. Traditionally, air is not conducive to diagnostic ultrasound, but the artifacts it creates can be used to give clues about certain conditions. Recently this artifact has been proposed as a means to identify free peritoneal air. Several small studies have shown promise for the technique, but further investigation is warranted. In this study the investigators will generate a database of standardized abdominal ultrasound images in subjects undergoing laparoscopic surgery. During this surgery, the peritoneal cavity is intentionally insufflated with air. The majority of this is removed at the end of the case, but small volumes of air remain, as evidence by the presence of air on CT scan when performed shortly after surgery. The investigators will obtain a standardized set of images preoperatively and post operatively which will then be reviewed in a blinded fashion by three expert reviewers, one each from radiology, surgery and emergency medicine, with data analysis to determine sensitivity and specificity of ultrasound for free air.

Interventions

DIAGNOSTIC_TESTPre-Operative Transabdominal Ultrasound

Pre-Operative Transabdominal Ultrasound evaluation of the right upper quadrant of the abdomen. Examination with be performed with low frequency curvilinear transducer and high frequency linear transducer at 5 standardized locations along the right costal margin followed by a 10 second sweep along the costal margin from the xyphoid process to the mid-axillary line

DIAGNOSTIC_TESTPost-Operative Transabdominal Ultrasound

Post-Operative Transabdominal Ultrasound evaluation of the right upper quadrant of the abdomen. Examination with be performed with low frequency curvilinear transducer and high frequency linear transducer at 5 standardized locations along the right costal margin followed by a 10 second sweep along the costal margin from the xyphoid process to the mid-axillary line

Sponsors

David Blehar
Lead SponsorOTHER

Study design

Observational model
COHORT
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

* Subjects scheduled for elective laparoscopic surgery * Age 18 or greater

Exclusion criteria

* Age less than 18 * Pregnant * unable to provide consent

Design outcomes

Primary

MeasureTime frameDescription
Presence of Free Air Artifact on UltrasoundFollowing completion of laparoscopic surgery, average of 2 hours, up to 1 day.Hyperechoic echo originating from peritoneal stripe

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026