Cantineau J P, Escourrou P, Sartene R, Gaultier C, Goldman M
Laboratoire d'Explorations Fonctionelles Respiratoire, Hospital Antoine Beclere, INSERM CJF 8909 Clamart, France.
Chest. 1992 Oct;102(4):1145-51. doi: 10.1378/chest.102.4.1145.
To assess the accuracy of the respiratory inductive plethysmograph (RIP) during sleep in obese patients with obstructive sleep apnea (OSA), we monitored 13 patients with OSA during wakefulness and nocturnal sleep with simultaneous measurements of tidal volume from RIP and integrated airflow. Patients wore a tightly fitting face mask with pneumotachograph during wakefulness and sleep. Calibrations were performed during wakefulness prior to sleep and compared with subsequent wakeful calibrations at the end of the study. Patients maintained the same posture during sleep (supine, 11; lateral, two) as during calibrations. There were no significant differences in calibrations before sleep and after awakening. The mean error in 13 patients undergoing RIP measurements of tidal volume during wakefulness was -0.7 +/- 3.4 percent while that during sleep was 2.1 +/- 14.9 percent (p < 0.001). The standard deviation (SD) of the differences between individual breaths measured by RIP and integrated airflow was 9.8 +/- 5.5 percent during wakefulness and 25.5 +/- 18.6 percent during sleep (p < 0.001). During both wakefulness and sleep, errors in RIP tidal volume were not significantly correlated with body mass index. In 12 patients with at least 10 percent time in each of stages 1 and 2 sleep, SD was greater in stage 2 sleep compared with wakefulness and stage 1 (p < 0.001). In three patients who manifested all stages of sleep, SD was greater in REM sleep than in wakefulness and all stages of non-REM sleep (p < 0.001). In three patients who manifested all stages of sleep, SD was greater in REM sleep than in wakefulness and all stages of non REM sleep (p < 0.001). This was associated with paradoxic motion of the rib cage in two patients during REM. We conclude that, despite increased errors in individual breath measurements during sleep, more marked during stages 2 and REM sleep, RIP is clinically useful to measure ventilation quantitatively in obese patients with sleep apnea. The criterion of a decrease of 50 percent in tidal volume assessed by RIP is appropriate to define hypopneas in such patients.
为评估呼吸感应体积描记器（RIP）在肥胖阻塞性睡眠呼吸暂停（OSA）患者睡眠期间的准确性，我们对13例OSA患者在清醒和夜间睡眠期间进行了监测，同时测量RIP的潮气量和整合气流。患者在清醒和睡眠期间佩戴带有呼吸速度描记器的紧密贴合面罩。在睡眠前的清醒状态下进行校准，并与研究结束时随后的清醒校准进行比较。患者在睡眠期间保持与校准时相同的姿势（仰卧位11例；侧卧位2例）。睡眠前和醒来后的校准无显著差异。13例患者清醒时RIP测量潮气量的平均误差为-0.7±3.4%，而睡眠期间为2.1±14.9%（p<0.001）。RIP测量的单次呼吸与整合气流之间差异的标准差（SD）在清醒时为9.8±5.5%，睡眠期间为25.5±18.6%（p<0.001）。在清醒和睡眠期间，RIP潮气量的误差与体重指数均无显著相关性。在12例在睡眠1期和2期各至少有10%时间的患者中，2期睡眠时的SD大于清醒和1期睡眠时（p<0.001）。在3例表现出所有睡眠阶段的患者中，快速眼动（REM）睡眠时的SD大于清醒和所有非快速眼动睡眠阶段（p<0.001）。在3例表现出所有睡眠阶段的患者中，REM睡眠时的SD大于清醒和所有非快速眼动睡眠阶段（p<0.001）。这与2例患者在REM期间胸廓的反常运动有关。我们得出结论，尽管睡眠期间单次呼吸测量的误差增加，在2期和REM睡眠期间更明显，但RIP在临床上对于定量测量肥胖睡眠呼吸暂停患者的通气是有用的。通过RIP评估潮气量减少50%的标准适用于定义此类患者的呼吸浅慢。
