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CompletedNCT03505476Updated Apr 13, 2025Results posted

Optimizing the Previs Device for Prediction of Postoperative Ileus

An interventional study of Entac Medical device application and Patient Daily Assessment in Ileus, sponsored by Jennifer Hrabe. Completed at 1 site in United States. Open to participants aged 18 Years to 100 Years. Per ClinicalTrials.gov, last updated 2025-04-13.

Sponsored by Jennifer Hrabe · Not applicable, Interventional, and Diagnostic

Phase
Not applicable
Study type
Interventional
Enrollment
203
Allocation
Not applicable
Ages
18 Years to 100 Years
Sex
All
01

Study summary

The research proposed in this study will develop a noninvasive prototype device that will capture intestinal sounds, process signals, and display predictive information in real-time at the point-of-care using algorithms already developed at this institution.

Read the detailed description

Following major abdominal surgery, up to 30% of patients develop a poorly understood condition known as ileus. When ileus occurs, the bowels shut down and patients often develop abdominal dissension, nausea, vomiting, and even more serious complications. Because this condition does not develop until many days after surgery has been completed, clinicians do not know if they should begin allowing patients to eat or withhold nutrition until they show signs of bowel function such as passing gas or having bowel movements. Clinicians have different approaches but none are ideal: 1) feed all patients early and the ones that develop an ileus will have their diets reverse, suction tube placed in their stomach, and hopefully don't get develop more serious complications, or 2) don't feed patients until they pass gas or have a bowel movement, which delays nutrition and prolongs hospital stays for the 70% of patients who will not develop an ileus

Participants in this study will be asked to wear a 3-ounce device that adheres to the skin of the abdominal wall for 10 days. They will also be asked to answer questions each day of their hospital stay regarding how they have tolerated eating.

02

Conditions studied

  • Ileus

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Keywords

  • Ileus
  • Abdominal surgery
  • Bowel obstruction
  • Postoperative Ileus
03

Who can participate

Ages eligible
18 Years to 100 Years
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

Patients undergoing elective intestinal resection surgery by the colorectal surgery service at UIHC.

Age 18 to 100.

Exclusion criteria

Exclusion Criteria:

Allergies to any of the device components. Inability to have prototype device applied to their abdominal wall due to a condition (ie:fistulas, stomas, drains, etc).

04

Study design

Phase
Not applicable
Primary purpose
Diagnostic
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
203 participants (actual)

Study arms

  • Experimental
    Study Participants

    Device: Entac Medical device application Other: Patient Daily Assessment Other: Patient Discharge Assessment

    Device: Entac Medical device application · Other: Patient Daily Assessment · Other: Patient Discharge Assessment

Interventions

  • DeviceEntac Medical device application

    Subjects will wear a 3-inch by 3-inch stethoscope device that adheres to the skin of the abdomen via FDA approved adhesive material. It will be applied either in the operating room at the completion of surgery or in the recovery room. The device will remain on the abdomen until discharge or for 10 days, whichever comes first.

  • OtherPatient Daily Assessment

    The research team will ask questions of the subject regarding nausea, vomiting, passage of flatus, return of bowel function, and satisfaction with the device every day that the subject is hospitalized.

  • OtherPatient Discharge Assessment

    The research team will ask questions of the subject regarding satisfaction or dissatisfaction with having the device placed and attached to their abdomen.

05

What researchers measure

Primary outcomes

  1. Device Sensitivity for Predicting Ileus.

    Calculate the sensitivity of the device to predict ileus, as defined by the number of patients with device-predicted ileus (true positive) as compared to the number both with device-predicted ileus and with ileus that the device did not predict (true positive + false negative).

    Time frame: Each patient's device's data was assessed at day 15.

  2. Device Specificity for Predicting Ileus

    Calculate the specificity of the device to predict ileus, as defined by the number of patients where the device correctly predicted no ileus (true negative) as compared to the number both with device correctly predicting no ileus and device incorrectly predicting ileus (true negative plus false positive).

    Time frame: Each patient's device's data was assessed at day 15.

  3. Device Positive Predictive Value for Predicting Ileus

    Calculate the positive predictive value of the device to predict ileus, as defined by the number of patients with device-predicted ileus (true positive) as compared to the number both with device-predicted ileus and with device incorrectly predicting ileus (true positive plus false positive).

    Time frame: Each patient's device's data was assessed at day 15.

  4. Device Negative Predictive Value for Predicting Ileus

    Calculate the negative predictive value of the device to predict ileus, as defined by the number of patients where the device correctly predicted no ileus (true negative) as compared to the number both with device correctly predicted no ileus and with ileus the device did not predict (true negative plus false negative).

    Time frame: Each patient's device's data was assessed at day 15.

06

Results

Posted Apr 13, 2025

Participant flow

Participant flow — Overall Study
MilestoneStudy Participants
Started203
Completed75
Not completed128
Withdrew: Physician decision18
Withdrew: Device malfunctioned101
Withdrew: Data corrupt6
Withdrew: Device application insufficiant3

Outcome measures

PrimaryDevice Sensitivity for Predicting Ileus.

Calculate the sensitivity of the device to predict ileus, as defined by the number of patients with device-predicted ileus (true positive) as compared to the number both with device-predicted ileus and with ileus that the device did not predict (true positive + false negative).

Time frame:
Each patient's device's data was assessed at day 15.
Reported as:
Count of participants · Participants
Device Sensitivity for Predicting Ileus.
ParticipantsStudy Participants
Patients with Ileus whose device predicted ileus (true positive).12
Patients with ileus whose device did not predict ileus (false negative).2
Patients without ileus whose device predicted ileus (false positive).22
Patients without ileus whose device did not predict ileus (true negative).39
PrimaryDevice Specificity for Predicting Ileus

Calculate the specificity of the device to predict ileus, as defined by the number of patients where the device correctly predicted no ileus (true negative) as compared to the number both with device correctly predicting no ileus and device incorrectly predicting ileus (true negative plus false positive).

Time frame:
Each patient's device's data was assessed at day 15.
Reported as:
Count of participants · Participants
Device Specificity for Predicting Ileus
ParticipantsStudy Participants
Patients with ileus whose device predicted ileus (true positive)12
Patients with ileus whose device did not predict ileus (false negative)2
Patients without ileus whose device predicted ileus (false positive)22
Patients without ileus whose device did not predict ileus (true negative)39
PrimaryDevice Positive Predictive Value for Predicting Ileus

Calculate the positive predictive value of the device to predict ileus, as defined by the number of patients with device-predicted ileus (true positive) as compared to the number both with device-predicted ileus and with device incorrectly predicting ileus (true positive plus false positive).

Time frame:
Each patient's device's data was assessed at day 15.
Reported as:
Count of participants · Participants
Device Positive Predictive Value for Predicting Ileus
ParticipantsStudy Participants
Patients with ileus whose device predicted ileus (true positive)12
Patients with ileus whose device did not predict ileus (false negative)2
Patients without ileus whose device predicted ileus (false positive)22
Patients without ileus whose device did not predicted ileus (true negative)39
PrimaryDevice Negative Predictive Value for Predicting Ileus

Calculate the negative predictive value of the device to predict ileus, as defined by the number of patients where the device correctly predicted no ileus (true negative) as compared to the number both with device correctly predicted no ileus and with ileus the device did not predict (true negative plus false negative).

Time frame:
Each patient's device's data was assessed at day 15.
Reported as:
Count of participants · Participants
Device Negative Predictive Value for Predicting Ileus
ParticipantsStudy Participants
Patients with ileus whose device predicted ileus (true positive)12
Patients with ileus whose device did not predict ileus (false negative)2
Patients without ileus whose device predicted ileus (false positive)22
Patients without ileus whose device did not predicted ileus (true negative)39

Adverse events

Collected over Adverse event data was collected on all subjects until their study participation is completed. (typically at or around 14 days). Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Study Participants0/203 (0%)0/203 (0%)0/203 (0%)

Baseline characteristics

Age, Categorical
Age, Categorical(Participants)Study Participants
<=18 years0
Between 18 and 65 years139
>=65 years64
Sex: Female, Male
Sex: Female, Male(Participants)Study Participants
Female108
Male95
Ethnicity (NIH/OMB)
Ethnicity (NIH/OMB)(Participants)Study Participants
Hispanic or Latino4
Not Hispanic or Latino197
Unknown or Not Reported2
Race (NIH/OMB)
Race (NIH/OMB)(Participants)Study Participants
American Indian or Alaska Native1
Asian2
Native Hawaiian or Other Pacific Islander0
Black or African American2
White195
More than one race2
Unknown or Not Reported1
Region of Enrollment
Region of Enrollment(participants)Study Participants
United States203
07

Study locations

1 site
  • University of Iowa
    Iowa City, Iowa 52242, United States
08

References and documents

Study documents

  • Study protocol · Sep 28, 2020
  • Statistical analysis plan · Dec 11, 2018

Documents are hosted by the registry — open the source record to download them.

Individual participant data

Plan to share: No

09

Registry details

Key details

Study ID
NCT03505476
Lead sponsor
Jennifer Hrabe
Responsible party
Jennifer Hrabe (Clinical Assistant Professor, University of Iowa) — Sponsor-investigator
First posted
Apr 23, 2018
Start date
Apr 24, 2018
Primary completion
Jun 5, 2023
Completion
Jun 5, 2023
Results posted
Apr 13, 2025
Last update
Apr 13, 2025

Study contacts

Jennifer Hrabe
principal investigator · University of Iowa

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
Yes
View the source record on ClinicalTrials.gov ↗

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