Acid-base Balance in Patients Undergoing Colonoscopy

Study Overview
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Brief Summary
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The purpose of this study is to determine whether fluid administration in patients undergoing colonoscopy should affect acid-base disorder in term of the strong ion differences.

Detailed Description
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This is a prospective, double-blinded, randomized control trial. The study enrolls 90 consecutive outpatients, well-prepared bowel, scheduled to undergo routine colonoscopy for screening, surveillance, or diagnosis of colorectal diseases. At the outpatient clinic, the co-researcher invites patients who meet the inclusion criteria to join the study. The process of the project is explained to the interested patients in details before an informed consent is obtained and the first blood sample is conducted. On the day of colonoscopy, all participants are randomized equally into three groups: Normal saline solution (NSS, n = 30) as control group, lactated Ringer's solution (LRS, n = 30) and acetated Ringer's solution (ARS, n = 30) as treatment groups. The second blood sample is obtained from patients via 20-gauge needle in either forearm immediately before an allocated intravenous (IV) fluid administered on the same site. The volume of fluid is calculated by means of Holliday and Segar formula. The colonoscopy under total intravenous anesthesia is performed between 9:00 a.m. and 3:00 p.m. At the end of colonoscopy, the patients spontaneously wake up in the recovery room. After they gain conscious and all vital signs are stable; the intravenous fluid is off and the third blood sample is taken in the other forearm. After completion of the procedure, the patient is advised to follow the discharge instructions.

Official Title
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Intravenous Fluid Administration in Patients Undergoing Colonoscopy: Double Blind, Randomised Clinical Trial of Underlying Acid-base Derangement

Conditions
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Colonoscopy, Bowel Preparation

Intervention / Treatment
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* Drug: Lactated Ringer's solution
* Drug: Normal saline solution
* Drug: Acetate Ringer's solution


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: male or non-pregnant non-lactating female out-patient scheduled for routine colonoscopy over 18 years of age eligible for taking PEG or NaP for bowel preparation, and willing to sign informed consent. Exclusion Criteria: insulin-dependant diabetes renal insufficiency (creatinine >2.0 mg⁄ dL) renal dialysis uncontrolled congestive heart failure (American Heart Association Classification III or IV congestive heart failure) unstable angina untreated cardiac arrhythmia ileus and⁄or acute obstruction or perforation ileostomy presence of a colostomy history of a partial colon resection active gastrointestinal bleeding.

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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Accepts Healthy Volunteers

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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Normal saline solution<br>Blood sample is obtained from patient in either forearm immediately before a Normal saline solution administered on the same site. The volume of fluid administration is calculated by means of Holliday and Segar formula. | Drug: Normal saline solution<br>* Normal saline solution is administered. The volume of fluid administration is calculated by means of Holliday and Segar formula.<br>* Other names: NSS;|
| Active Comparator: Lactated Ringer's solution<br>Lactated Ringer's solution is administered. The volume of fluid administration is calculated by means of Holliday and Segar formula. | Drug: Lactated Ringer's solution<br>* Lactated Ringer's solution is administered. The volume of fluid administration is calculated by means of Holliday and Segar formula.<br>* Other names: LRS;|
| Active Comparator: Acetate Ringer's solution<br>Acetate Ringer's solution is administered. The volume of fluid administration is calculated by means of Holliday and Segar formula. | Drug: Acetate Ringer's solution<br>* Acetate Ringer's solution is administered. The volume of fluid administration is calculated by means of Holliday and Segar formula.<br>* Other names: ARS;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Patients with Acid-base disorder as a Measure of Strong Ion Difference. | The strong ion difference (SID) is calculated by means of the differences between the positively and negatively charged strong ions in plasma. The strong ion difference affected by bowel preparation and intravenous fluid administration during colonoscopy. | 3 days |