Rimpilä Ville, Jernman Riina, Lassila Katariina, Uotila Jukka, Huhtala Heini, Mäenpää Johanna, Polo Olli
Faculty of Medicine and Life Sciences, University of Tampere, PL 100, 33014, Tampere, Finland; Unesta Research Center, Näsilinnankatu 48 D, 4th Floor, 33520, Tampere, Finland.
Department of Obstetrics and Gynaecology, Tampere University Hospital, PL 2000, 33521, Tampere, Finland.
Sleep Med. 2017 Aug;36:67-74. doi: 10.1016/j.sleep.2017.05.005. Epub 2017 May 29.
Sleep during pregnancy involves a physiological challenge to provide sufficient gas exchange to the fetus. Enhanced ventilatory responses to hypercapnia and hypoxia may protect from deficient gas exchange, but sleep-disordered breathing (SDB) may predispose to adverse events. The aim of this study was to analyze sleep and breathing in healthy pregnant women compared to non-pregnant controls, with a focus on CO changes and upper-airway flow limitation.
Healthy women in the third trimester and healthy non-pregnant women with normal body mass index (BMI) were recruited for polysomnography. Conventional analysis of sleep and breathing was performed. Transcutaneous carbon dioxide (TcCO) was determined for each sleep stage. Flow-limitation was analyzed using the flattening index and TcCO values were recorded for every inspiration.
Eighteen pregnant women and 12 controls were studied. Pregnancy was associated with shorter sleep duration and more superficial sleep. Apnea-hypopnea index, arterial oxyhemoglobin desaturation, flow-limitation, snoring or periodic leg movements were similar in the two groups. Mean SaO and minimum SaO were lower and average heart rate was higher in the pregnant group. TcCO levels did not differ between groups but variance of TcCO was smaller in pregnant women during non-rapid eye movement (NREM). TcCO profiles showed transient TcCO peaks, which seem specific to pregnancy.
Healthy pregnancy does not predispose to SDB. Enhanced ventilatory control manifests as narrowing threshold of TcCO between wakefulness and sleep. Pregnant women have a tendency for rapid CO increases during sleep which might have harmful consequences if not properly compensated.
孕期睡眠涉及一项生理挑战，即要为胎儿提供充足的气体交换。增强对高碳酸血症和低氧血症的通气反应可能有助于防止气体交换不足，但睡眠呼吸紊乱（SDB）可能会引发不良事件。本研究的目的是分析健康孕妇与非孕妇对照组的睡眠和呼吸情况，重点关注二氧化碳（CO）变化和上气道气流受限情况。
招募孕晚期的健康女性和体重指数（BMI）正常的健康非孕女性进行多导睡眠图检查。对睡眠和呼吸进行常规分析。测定每个睡眠阶段的经皮二氧化碳（TcCO）水平。使用扁平指数分析气流受限情况，并记录每次吸气时的TcCO值。
共研究了18名孕妇和12名对照组女性。怀孕与较短的睡眠时间和较浅的睡眠有关。两组的呼吸暂停低通气指数、动脉血氧血红蛋白饱和度降低、气流受限、打鼾或周期性腿部运动情况相似。孕妇组的平均血氧饱和度（SaO）和最低SaO较低，平均心率较高。两组之间的TcCO水平无差异，但在非快速眼动（NREM）期间，孕妇的TcCO方差较小。TcCO曲线显示出短暂的TcCO峰值，这似乎是孕期特有的。
健康怀孕不会导致睡眠呼吸紊乱。增强的通气控制表现为清醒和睡眠之间TcCO的阈值变窄。孕妇在睡眠期间有CO快速升高的趋势，如果得不到适当补偿，可能会产生有害后果。
