This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by Szpisjak, D. F. Articles by Klions, K. D. Search for Related Content PubMed PubMed Citation Articles by Szpisjak, D. F. Articles by Klions, K. D. Related Collections Equipment Technology

---

TECHNOLOGY, COMPUTING, AND SIMULATION

Oxygen Consumption with Mechanical Ventilation in a Field Anesthesia Machine

Dale F. Szpisjak, MD^*,, Charles L. Lamb, MD, and Kenneth D. Klions, MD

*Department of Anesthesiology, Uniformed Services University of the Health Sciences, Bethesda, Maryland, and the Anesthesia Department, Fleet Hospital, Bremerton, Washington

Address correspondence and reprint requests to Dale F. Szpisjak, MD, Department of Anesthesiology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814. Address e-mail to dszpisjak{at}usuhs.mil.

Field anesthesia machines (FAM) with gas-powered ventilators have been developed for remote locations that may not have a central supply of oxygen. These ventilators may rapidly deplete oxygen cylinders, especially in patients with decreased pulmonary compliance. Our goal in this study was to determine oxygen consumption rates with a contemporary FAM in models of high (HC) and low (LC) pulmonary compliance. Oxygen consumption rates were tested using D cylinders (initial pressure 1700 psig) and the Narkomed® M FAM, which uses an air injector to decrease compressed gas consumption by entraining room air as part of the drive gas. Three different tidal volumes (Vt) were tested (500, 750, and 1000 mL) with HC and LC lung models, and the fresh gas flow rate was 1 L/min. Respiratory rate was constant at 10 breaths/min. Oxygen consumption varied directly with Vt and inversely with compliance, increasing from 4.8 ± 0.07 L/min with the HC-500 mL Vt model to 6.2 ± 0.05 L/min with the LC-1000 mL Vt model. D cylinder duration ranged from 56.8 ± 0.4 to 73.6 ± 1.0 minutes. Assuming oxygen fresh gas flow of 1 L/min, calculating tank duration with the fastest consumption rate underestimated the tank duration for more compliant and smaller Vt models but provided a greater margin of patient safety.

This article has been cited by other articles:

				D. F. Szpisjak, E. N. Javernick, R. R. Kyle, and P. N. Austin Oxygen Consumption of a Pneumatically Controlled Ventilator in a Field Anesthesia Machine Anesth. Analg., December 1, 2008; 107(6): 1907 - 1911. [Abstract] [Full Text] [PDF]