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Warm water infusion during sedated colonoscopy does not decrease amount of sedation medication used
Brent Y Lee1, Ronald Katon, Daniel Herzig
1Division of Gastroenterology, Oregon Health & Science University, Portland, Oregon 97239, USA.
Background:
Water infusion versus air insufflation during colonoscope insertion has been suggested to reduce patient discomfort and decrease sedation medication requirements. Warm water is thought to further facilitate colonoscopy perhaps by decreasing colon spasm.
Objective:
To compare the utility of warm (35°-38°C) versus cool (20°-23°C) water infused during colonoscopic insertion by measuring patient sedation medication use and discomfort scores between the warm and cool water groups.
Design:
Randomized, controlled, double-blinded study.
Setting:
Outpatient endoscopy unit at an academic medical center.
Patients:
A total of 175 adults.
Intervention:
Elective outpatient sedated screening colonoscopies.
Main Outcome Measurements:
Sedation medication used, pain scores, cecal intubation rate, endoscopy times, satisfaction scores, and patient willingness to repeat procedures.
Results:
There was no significant difference in sedation medication requirement during colonoscopy with the use of warm or cool water (fentanyl 83.6 ± 29.0 μg vs 87.6 ± 39.6 μg; P = .45; midazolam 3.3 ± 1.2 mg vs 3.3 ± 1.3 mg; P = .91). There was no significant difference in patient pain scores or satisfaction scores. Cecal intubation rates (100%) were similar. There was no significant difference in cecal intubation times (6 minutes 40 seconds ± 4 minutes 9 seconds vs 7 minutes 49 seconds ± 4 minutes 0 seconds; P = .06) between the warm and cool water groups. All patients were willing to repeat the colonoscopy by using the same method in both groups.
Limitations:
Limited generalizability to patients undergoing screening sedated colonoscopies with good to excellent bowel preparation.
Conclusion:
Water does not need to be warmed before infusion in patients undergoing sedated colonoscopies.
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