+ Site Statistics
References:
54,258,434
Abstracts:
29,560,870
PMIDs:
28,072,757
+ Search Articles
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ PDF Full Text
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Translate
+ Recently Requested

Evaluation of heated humidifiers for use on intubated patients: a comparative study of humidifying efficiency, flow resistance, and alarm functions using a lung model



Evaluation of heated humidifiers for use on intubated patients: a comparative study of humidifying efficiency, flow resistance, and alarm functions using a lung model



Intensive Care Medicine 28(6): 731-739



Evaluation of humidification efficiency, flow resistance, and alarm functions of heated humidifiers (HH;(Kendall-Aerodyne-delta, Fisher&Paykel-MR 730; Dräger-Aquapor; Puritan-Bennett-Cascade II) in accordance with ISO/EN-8185:1997 and on a ventilated lung model in accordance with ISO/EN-9360:2000. Humidification efficiency was evaluated by (a) measuring the water content of the inspiratory air on perfusion with different gas flows, (b) measuring the water loss of a lung model, and (c) simultaneous measurement of the in- and expiratory water content with a capacitive hybrid sensor. The resistance characteristics were measured, the data were compared with a mathematical approximation. The alarm functions were determined. The humidification efficiency of HHs is a function of gas flow and design characteristics. In HHs with tube heating it is possible to make settings at which the inspiratory humidity falls below the minimal value of 33 mgH(2)O/l stipulated by ISO/EN-8185:1997. The inspiratory resistances extend from 0.5 to 4.4 cmH(2)O l(-1) s(-1); the expiratory flow resistances of the devices are low. The alarm functions of HHs with tube heating are inadequate for cases involving both "dry start" and "running dry." Efficiency data that allow a direct comparison with heat and moisture exchangers data according to ISO/EN-9360:2000 can also be determined for HH. HH do not prevent pulmonary water losses in intubated patients. These losses can exceed the physiological range. The airway resistance of the Cascade II prohibits its use in spontaneously breathing patients. The warning and shut-off features of HH are unacceptable and hazardous.

(PDF emailed within 0-6 h: $19.90)

Accession: 046010238

Download citation: RISBibTeXText

PMID: 12107679

DOI: 10.1007/s00134-002-1275-9


Related references

Temperature alarm for heated humidifiers. Anaesthesia 33(6): 527-530, 1978

Temperature alarm and cut-out system for use with heated water humidifiers. British Journal of Anaesthesia 52(5): 557-558, 1980

Hazard report. Mismatched electrical requirements between heated-wire breathing circuits and heated humidifiers can jeopardize patients. Health Devices 38(8): 267-269, 2010

Evaluation report: heated humidifiers. Journal of Medical Engineering & Technology 12(6): 282-286, 1988

Heat and moisture exchangers and heated humidifiers in acute lung injury/acute respiratory distress syndrome patients. Effects on respiratory mechanics and gas exchange. Intensive Care Medicine 32(4): 524-531, 2006

Ventilator-associated pneumonia in patients using HME filters and heated humidifiers. Irish Journal of Medical Science 182(4): 651-655, 2014

Performance of heated humidifiers with a heated wire according to ventilatory settings. Journal of Aerosol Medicine 14(1): 43-51, 2001

Performance of heated wire humidifiers: an in vitro study. Journal of Critical Care 22(3): 258-264, 2007

Mathematical model and minimal measurement system for optimal control of heated humidifiers in neonatal ventilation. Medical Engineering and Physics 32(5): 475-481, 2010

The maximum expiratory flow-volume in the evaluation of patients with lung disease. A comparative study with standard pulmonary function tests. American Journal of Medicine 46(1): 72-79, 1969

In vivo efficacy of heated and non-heated humidifiers during nasal continuous positive airway pressure (nCPAP)-therapy for obstructive sleep apnoea. Respiratory Medicine 94(4): 364-368, 2000

Effect of inspiratory flow rate on ventilation in lung transplant and intubated ICU patients. European Respiratory Journal 12(SUPPL 28): 56S, Sept, 1998

Comparative ex vivo study on humidifying function of three speaking valves with integrated heat and moisture exchanger for tracheotomised patients. Clinical Otolaryngology 40(6): 616-621, 2016

The clinical and microbiological comparison of the use of heated humidifiers and heat and moisture exchanger filters with Booster in mechanically ventilated patients. Tuberkuloz Ve Toraks 57(3): 259-267, 2010

Incompatibility of disposable heated-wire breathing circuits and heated-wire humidifiers. Health Devices 22(5-6): 300-301, 1993