Abstract
Objective. Mixtures of helium and oxygen are regaining a place in the treatment of obstruction of the upper and lower respiratory tract. The parenchymal changes during the course of IRDS or ARDS may also benefit from the reintroduction of helium/oxygen. In order to monitor and document the effect of low-density gas mixtures, we evaluated the Datex AS/3 Side Stream Spirometry module with D-lite® (Datex-Engstrom Instrumentarium Corporation, Finland) against two golden standards. Methods. Under conditions simulating controlled and spontaneous ventilation with gas mixtures of He (approx. 80, 50, and 20%)/O2 or N2 (approx. 21 and 79%)/O2, simultaneous measurements using Biotek Ventilator Tester (Bio-Tek Instr., Vermont, USA) or body plethysmograph (SensorMedics System, Anaheim, USA) were correlated with data from the spirometry module. Data were analyzed according to a statistical regression model resulting in a best-fit equation based on density, voltage, and volume measurements. Results. As expected, the D-lite (a modified Pitot tube) showed density-dependent behaviour. Regression equations and percentage deviation of estimated versus measured values were calculated. Conclusion. Measurements with the D-lite using low-density gases are satisfactorily contained in best-fit equations with a standard deviation of less than 5% during all ventilatory modes and mixtures.
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REFERENCES
Barach AL. Use of helium as a new therapeutic gas. Proc Soc Biol Med 1934; 32 (Dec): 462-464
Kass JE, Castriotta RJ. Heliox therapy in acute severe asthma. Chest 1995; 107: 757-760. See also Editorial Comment by Madison IM, Twin RS, 597-598
Manthous CA, Hall JB, Caputo MA et al. Heliox improves pulsus paradoxus and peak expiratory flow in non-intubated patients with severe asthma. Am J Respir Crit Care Med 1995 (Feb); 151 (2 Pt 1): 310-314
Gluck EH, Onorato DJ, Castriotta R. Helium-oxygen mixtures in intubated patients with status asthmaticus and respiratory acidosis. Chest 1990 (Sep); 98(3): 693-698
Petros AJ, Tulloh RMR, Wheatley E. Heli-NO: Enhanced gas exchange with nitric oxide in helium. Anesth Analg 1996; 83: 888-889 (Letter)
Wolf AR, Volgyesi GA. A modified Pitot tube for the accurate measurement of tidal volume in children. Anesthesiology 1987 (Nov); 67(5): 775-778
Porszasz J, Barstow TJ, Wasserman K. Evaluation of a symmetrically disposed Pitot tube flowmeter for measuring gas flow during exercise. J Appl Physiol 1994; 77(6): 2659-2665
Meriläinen P, Hänninen H, Tuomaala L. A novel sensor for routine continuous spirometry of intubated patients. J Clin Monit 1993; 9: 374-380
Bardoczky G, De Vries J, Meriläinen P et al. Side Stream Spirometry™. Datex Appliguide 1992
Prestele K, Franetzki M, Meerlender G. Viskositäts-und Dichteschwankungen von natürlichen Atemgasen und von Helium-Sauerstoff-Stickstoff-Gemischen in Abhängigkeit von Temperatur und Gaszusammensetzung. Respiration 1976; 33: 150-162
Johns DP, Preto JJ, Streeton JA. Measurement of gas viscosity with a Fleisch pneumotachograph. J Appl Physiol 1982; 53(1): 290-293
Kety SS. The theory and applications of the exchange of inert gas at the lungs and the tissues. Pharmacol Rev 1951; 3: 1-41
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Søndergaard, S., Kárason, S., Lundin, S. et al. Evaluation of a Pitot Type Spirometer in Helium/Oxygen Mixtures. J Clin Monit Comput 14, 425–431 (1998). https://doi.org/10.1023/A:1009978816071
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DOI: https://doi.org/10.1023/A:1009978816071