Suspension of respiration during end-expiration often is recommended to minimize body organ displacement between sequential image acquisitions. The purpose of this report is to evaluate techniques for end-expiratory breath- holding applicable to a pulmonary-compromised population. Eighty-seven consecutive outpatients with chronic pulmonary diseases and 31 healthy nonsmoking volunteers were recruited for the study. All subjects were asked to hold their breath in end-expiration while in the supine position (29 after breathing room air, 29 after hyperventilating room air for six breaths, and 29 after breathing O2 from a portable oxygen tank via nasal cannula until pulse-oximeter readings stabilized or reached 100%). Each volunteer was tested with all three methods. The mean length of time for a breath-hold on room air without hyperventilation was 9.2 seconds for the patients and 31.7 seconds for the volunteers. A breath-hold after hyperventilation of room air was timed at 12.3 seconds for the patients and 41.2 seconds for the volunteers, and after O2 administration, the breath-hold was 22.4 seconds for the patients and 60.9 seconds for the volunteers. No adverse effects occurred. The pulmonary-compromised patient can suspend respiration most successfully after O2 administration (P < .0001), whereas hyperventilation seems to be less beneficial. Nonpulmonary - compromised volunteers can hold their breath for longer periods of time.
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