We have located links that may give you full text access.
Clinical Trial
Journal Article
Randomized Controlled Trial
Efficacy of heat and moisture exchangers after changing every 48 hours rather than 24 hours.
Critical Care Medicine 1998 March
OBJECTIVE: To determine whether changing heat and moisture exchangers every 48 hrs rather than 24 hrs would affect their efficacy to preserve heat and moisture of expiratory gases.
DESIGN: Prospective, controlled, randomized, not blinded, study.
SETTING: Intensive care unit of a university hospital.
PATIENTS: Twenty-nine patients requiring controlled mechanical ventilation and paralysis for >2 days.
INTERVENTIONS: After randomization, the patients were allocated to one of the three following groups: a) group 1, ventilated for 24 hrs with a heat and moisture exchanger; b) group 2, ventilated for 48 hrs with the same heat and moisture exchanger; and c) group 3, ventilated for 48 hrs with a heated humidifier system.
MEASUREMENTS AND MAIN RESULTS: In each patient, during the inspiration phase, the following measurements were performed: a) peak and mean airway pressures; b) mean values of temperature; c) relative and absolute humidity of inspired gases. In each patient, measurements were performed after 24 hrs and after 48 hrs, where appropriate. After 24 hrs, patients in groups 1 and 2 had similar levels of temperature (30.1 +/- 2.7 degrees C and 29.2 +/- 2.3 degrees C), relative humidity (98.3 +/- 3.6% and 99.3 +/- 3.4%), and absolute humidity (29.1 +/- 2.1 and 29.3 +/- 2.4 mg H2O/L). Using the same heat and moisture exchanger for 48 hrs rather than 24 hrs did not affect its technical performance. Results showed the following: a) temperature, 24 hrs, 29.2 +/- 2.3 degrees C, 48 hrs, 28.7 +/- 1.9 degrees C; b) relative humidity, 24 hrs, 99.3 +/- 3.4%, 48 hrs, 99.2 +/- 1.7%; and c) absolute humidity, 24 hrs, 29.3 +/- 2.4 mg H2O/L, 48 hrs, 28.7 +/- 3.1 mg H2O/L. Peak and mean airway pressures did not change over the 48-hr study period, with identical tidal and minute volumes in the study patients. Higher levels of temperature and absolute humidity of inspired gases were observed in group 3, compared with groups 1 and 2 (p< .02).
CONCLUSIONS: Changing the heat and moisture exchanger after 48 hrs rather than 24 hrs did not affect its technical performance in terms of heat and water preservation of ventilatory gases. There is also some indirect evidence of very few, if any, changes in heat and moisture exchanger resistance. However, other large clinical trials should be undertaken to confirm the safety of extending the time between heat and moisture exchanger change. The heated humidifier, supplied with electric energy maintained high levels of humidification and temperature over the 48-hr study period.
DESIGN: Prospective, controlled, randomized, not blinded, study.
SETTING: Intensive care unit of a university hospital.
PATIENTS: Twenty-nine patients requiring controlled mechanical ventilation and paralysis for >2 days.
INTERVENTIONS: After randomization, the patients were allocated to one of the three following groups: a) group 1, ventilated for 24 hrs with a heat and moisture exchanger; b) group 2, ventilated for 48 hrs with the same heat and moisture exchanger; and c) group 3, ventilated for 48 hrs with a heated humidifier system.
MEASUREMENTS AND MAIN RESULTS: In each patient, during the inspiration phase, the following measurements were performed: a) peak and mean airway pressures; b) mean values of temperature; c) relative and absolute humidity of inspired gases. In each patient, measurements were performed after 24 hrs and after 48 hrs, where appropriate. After 24 hrs, patients in groups 1 and 2 had similar levels of temperature (30.1 +/- 2.7 degrees C and 29.2 +/- 2.3 degrees C), relative humidity (98.3 +/- 3.6% and 99.3 +/- 3.4%), and absolute humidity (29.1 +/- 2.1 and 29.3 +/- 2.4 mg H2O/L). Using the same heat and moisture exchanger for 48 hrs rather than 24 hrs did not affect its technical performance. Results showed the following: a) temperature, 24 hrs, 29.2 +/- 2.3 degrees C, 48 hrs, 28.7 +/- 1.9 degrees C; b) relative humidity, 24 hrs, 99.3 +/- 3.4%, 48 hrs, 99.2 +/- 1.7%; and c) absolute humidity, 24 hrs, 29.3 +/- 2.4 mg H2O/L, 48 hrs, 28.7 +/- 3.1 mg H2O/L. Peak and mean airway pressures did not change over the 48-hr study period, with identical tidal and minute volumes in the study patients. Higher levels of temperature and absolute humidity of inspired gases were observed in group 3, compared with groups 1 and 2 (p< .02).
CONCLUSIONS: Changing the heat and moisture exchanger after 48 hrs rather than 24 hrs did not affect its technical performance in terms of heat and water preservation of ventilatory gases. There is also some indirect evidence of very few, if any, changes in heat and moisture exchanger resistance. However, other large clinical trials should be undertaken to confirm the safety of extending the time between heat and moisture exchanger change. The heated humidifier, supplied with electric energy maintained high levels of humidification and temperature over the 48-hr study period.
Full text links
Related Resources
Trending Papers
Challenges in Septic Shock: From New Hemodynamics to Blood Purification Therapies.Journal of Personalized Medicine 2024 Februrary 4
Molecular Targets of Novel Therapeutics for Diabetic Kidney Disease: A New Era of Nephroprotection.International Journal of Molecular Sciences 2024 April 4
The 'Ten Commandments' for the 2023 European Society of Cardiology guidelines for the management of endocarditis.European Heart Journal 2024 April 18
A Guide to the Use of Vasopressors and Inotropes for Patients in Shock.Journal of Intensive Care Medicine 2024 April 14
Diagnosis and Management of Cardiac Sarcoidosis: A Scientific Statement From the American Heart Association.Circulation 2024 April 19
Essential thrombocythaemia: A contemporary approach with new drugs on the horizon.British Journal of Haematology 2024 April 9
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app
All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.
By using this service, you agree to our terms of use and privacy policy.
Your Privacy Choices
You can now claim free CME credits for this literature searchClaim now
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app