Nasogastric Tube Clamping Trial vs. Immediate Removal

Study Overview
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Brief Summary
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The primary objective is to assess the need of clamping nasogastric tubes (NG) before removal. Outcomes of patients admitted requiring nasogastric tube decompression will be compared. Patients with small bowel obstruction (SBO), post-operative ileus, and ileus on admission that require nasogastric tube placement will be included in the study. The patients will be divided into two groups when return of bowel function is suspected based on set criteria for automatic removal of nasogastric tube versus nasogastric tube clamp trial. Specific outcomes will be occurrence of nasogastric tube replacement, number of emeses if any, failure of clamp trial, aspiration pneumonia, and any other unplanned outcome.

Detailed Description
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A high volume of patients are admitted to hospitals yearly for bowel obstruction/ileus complications. Lifetime risk of small bowel obstruction varies from 0.1%-5% if patients have not undergone abdominal surgery, but increases to 30% if the patient underwent a prior abdominal surgery. Ileus is also a common complication in the short term post-operative period. Both of these conditions are initially treated with nasogastric tube decompression if the patient is having emesis. The investigators were unable to find any literature that shows a concrete volume of nasogastric tube output that was deemed the maximum for safe removal. Signs of return of bowel function can indicate it is safe to remove the nasogastric tube. These include flatus, bowel movements, decrease in nasogastric tube output amount, change of nasogastric tube output color from bilious (green) to more gastric (yellow) or salivary (clear/foamy) quality. Some physicians prefer to perform a clamp trial before removal of the nasogastric tube. The duration of the trial and cutoff amount of residual drainage varies among physicians. Regardless of the duration, the nasogastric tube is essentially stenting open the lower esophageal sphincter while it is left in place and not connected to suction. This, theoretically, places the patient at risk for aspiration and subsequent pneumonia. Information in the literature appears divided in regard to aspiration risk. This study hopefully will support the statement that it is safe to remove the nasogastric tube with signs of bowel function, without the need for clamp trials and thus avoiding any possible adverse outcomes associated with the trial. The investigators also anticipate that this study will provide objective guidelines on which patients will continue to improve after nasogastric tube removal.

Official Title
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Nasogastric Tube Clamping Trial: Is it Useful? A Proposed Algorithm for Removal.

Conditions
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Small Bowel Obstruction, Ileus

Intervention / Treatment
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* Other: No clamp trial
* Other: Clamp trial


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Males or females 18 years or older Admitted under any of the teaching surgical services for small bowel obstruction or ileus, or develops post-operative ileus Patient agreeable to participation in the study Exclusion Criteria: Under the age of 18 Patient self-removes the NG requiring replacement will be removed from study

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Immediate NG tube removal<br>Once the NG tube output is less than 500 mL over a 24 hour period with at least two other signs of return of bowel function the NG tube will be removed. Other signs of bowel function include flatus, bowel movement, change of NG tube output from bilious to more clear/frothy character, and hunger. | Other: No clamp trial<br>* Once the NG tube output is less than 500 mL over a 24 hour period with at least two other signs of return of bowel function the NG tube will be removed. Other signs of bowel function include flatus, bowel movement, change of NG tube output from bilious to more clear/frothy character, and hunger.<br>|
| Active Comparator: NG tube clamp trial<br>Once the NG tube output is less than 500 mL over a 24 hour period with at least two other signs of return of bowel function, a 4 hour clamp trial will be performed. Other signs of bowel function include flatus, bowel movement, change of NG tube output from bilious to more clear/frothy character, and hunger. The NG tube will be taken off of suction and clamped. The NG tube is then reconnected to suction at the end of the four hour clamp trial and removed if less 125 mL drains or kept in place if greater than 125 mL drains. The same initial criteria are used again to determine if a clamp trial will be performed after 24 hours. | Other: Clamp trial<br>* Once the NG tube output is less than 500 mL over a 24 hour period with at least two other signs of return of bowel function, a 4 hour clamp trial will be performed. Other signs of bowel function include flatus, bowel movement, change of NG tube output from bilious to more clear/frothy character, and hunger. The NG tube will be taken off of suction and clamped. The NG tube is then reconnected to suction at the end of the four hour clamp trial and removed if less 125 mL drains or kept in place if greater than 125 mL drains. The same initial criteria are used again to determine if a clamp trial will be performed after 24 hours.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Necessity of replacement of NG tube | This measure looks at if the NG tube is replaced in either arm of the study after removal. | Through study completion, an average of 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pulmonary complications | This outcome looks at any episodes of aspiration pneumonia, pneumonitis, or pneumothorax. | Through study completion, an average of 1 year | 
| Days until discharge | This outcome will look at the number of days until discharge for all patients in each arm. | Through study completion, an average of 1 year | 
| Emesis episodes after NG tube removal | This outcome is measured as the number of patients who had an episode of emesis after NG tube removal prior to discharge. | Through study completion, an average of 1 year | 
| Days until general diet reached | This outcome is measured by looking at how many days it takes from the time of ileus or SBO diagnosis to reach a general diet. | Through study completion, an average of 1 year |