Point of Care Ultrasound for Diagnosis of Abdominal Free Air

Utility of Bedside Ultrasound for Diagnosis of Intraperitoneal Free Air

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.

Study Overview

• Status: Completed
• Conditions: Free Air in Abdomen
• Intervention / Treatment: Diagnostic test: Pre-Operative Transabdominal Ultrasound; Diagnostic test: Post-Operative Transabdominal Ultrasound

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.

• Study Type: Observational
• Enrollment (Actual): 100

Contacts and Locations

Study Locations

• United States
  • Massachusetts
    • Worcester, Massachusetts, United States, 01655
      • UMASS Memorial Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Subjects drawn from population of surgical patients at UMassMemorial Medical center undergoing elective laparoscopic surgery.

Description

Inclusion Criteria:

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

Exclusion Criteria:

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

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

Participants undergoing laparoscopy; Participants undergoing laparoscopic abdominal surgery with surgical insufflation receiving pre-operative transabdominal ultrasound and post-operative transabdominal ultrasound.

Diagnostic test: Pre-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 test: Post-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

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Presence of Free Air Artifact on Ultrasound	Hyperechoic echo originating from peritoneal stripe	Following completion of laparoscopic surgery, average of 2 hours, up to 1 day.

Collaborators and Investigators

• Sponsor: David Blehar
• Investigators: Principal Investigator: David Blehar, MD, UMass Medical School

Study record dates

Study Major Dates

• Study Start (Actual): November 1, 2018
• Primary Completion (Actual): October 1, 2019
• Study Completion (Actual): October 1, 2019

Study Registration Dates

• First Submitted: October 19, 2018
• First Submitted That Met QC Criteria: October 23, 2018
• First Posted (Actual): October 25, 2018

Study Record Updates

• Last Update Posted (Actual): November 6, 2019
• Last Update Submitted That Met QC Criteria: November 4, 2019
• Last Verified: November 1, 2019

More Information

Terms related to this study

• Keywords: laparoscopic surgery; transabdominal ultrasound; Free air
• Additional Relevant MeSH Terms: Digestive System Diseases; Peritoneal Diseases; Pneumoperitoneum
• Other Study ID Numbers: H-00013680

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: Yes
• product manufactured in and exported from the U.S.: Yes