title: The effect of atmospheric pressure on ventricular assist device output.
abstract: The effect of cabin pressure change on the respiratory system during flight is well documented in the literature, but how the change in atmospheric pressure affects ventricular assist device (VAD) output flow has not been studied yet. The purpose of our study was to evaluate the change in VAD output using a mock circulatory system in a low-pressure chamber mimicking high altitude. Changes in output and driving pressure were measured during decompression from 1.0 to 0.7 atm and pressurization from 0.7 to 1.0 atm. Two driving systems were evaluated: the VCT system and the Mobart system. In the VCT system, output and driving pressure remained the same during decompression and pressurization. In the Mobart system, the output decreased as the atmospheric pressure dropped and recovered during pressurization. The lowest output was observed at 0.7 atm, which was 80% of the baseline driven by the Mobart system. Under a practical cabin pressure of 0.8 atm, the output driven by the Mobart system was 90% of the baseline. In the Mobart system, the output decreased as the atmospheric pressure dropped, and recovered during pressurization. However, the decrease in output was slight. In an environment where the atmospheric pressure changes, it is necessary to monitor the diaphragmatic motion of the blood pump and the driving air pressure, and to adjust the systolic:diastolic ratio as well as the positive and negative pressures in a VAD system.
authors.affiliation: Department of Clinical Engineering, Hirosaki University School of Medicine and Hospital, 53 Hon-cho, Hirosaki, Aomori 036-8563, Japan. me-goto@cc.hirosaki-u.ac.jp
authors.forename: Takeshi
authors.initials: T
authors.lastname: Goto
authors.forename: Masaharu
authors.initials: M
authors.lastname: Sato
authors.forename: Akio
authors.initials: A
authors.lastname: Yamazaki
authors.forename: Wakako
authors.initials: W
authors.lastname: Fukuda
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Watanabe
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Daitoku
authors.forename: Masahito
authors.initials: M
authors.lastname: Minakawa
authors.forename: Kozo
authors.initials: K
authors.lastname: Fukui
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Ikuo
authors.initials: I
authors.lastname: Fukuda
mesh_terms: D001274:Atmospheric Pressure; D004867:Equipment Design; D006353:Heart-Assist Devices; D006801:Humans; D008955:Models, Cardiovascular; D011673:Pulsatile Flow