94名飞行员加压呼吸训练中的心电图变化分析

Analysis of electrocardiogram changes during positive pressure breath training in 94 pilots

目的根据飞行员加压呼吸训练中心电图的改变特征,为加压呼吸耐力的评定提供生理依据。方法分析2000～2004年间94名飞行员在行地面加压呼吸训练时的心电图变化特点。94名飞行员均进行余压值分别为5.88kPa(44.1mmHg)、7.84kPa(58.8mmHg)以及9.80kPa(73.5mmHg)的加压呼吸训练,持续时间3min,间隔休息5min。在实施各余压值加压时进行标准肢体导联心电监测,每分钟记录1次。结果加压呼吸训练中心电图变化特征为:心率随加压值的增高而增加,期前收缩、传导阻滞等心律失常偶有发生(共计7.4%)。心电图波形以P波电压增加最常见,其次是T波降低;P-R间期随余压值增加而减小,各组与未加压时比较有显著差异(P<0.05)。T波电压呈递减趋势,仅在9.80kPa时与地面比较有显著性差异(P<0.05)。P波电压变化较显著,余压值达9.80kPa时较地面未加压时增加了48.0%,呈递增趋势,有显著性差异(P>0.05)。结论对加压呼吸训练中出现的窦性心律不齐,偶发房性、室性期前收缩等在卸压后可自行消失,可评定为加压呼吸耐力合格。对房室传导阻滞、P波游走等异常心电图,应结合血压、主观反应做出耐力合格或不合格结论。

Objective To provide physiological evidences for evaluating positive pressure breathing （PPB） tolerance of pilots according to the electrocardiogram （ECG） changes in PPB training. Methods From 2000 to 2004, the ECG of 94 pilots was recorded during PPB training ,with the excessive pressure 5.88 kPa, 7.84 kPa and 9.80 kPa respectively, sustained 3 minutes with 5 minutes interval. The ECG of pilots in 12 standard leads was measured one time per minute for every excessive pressure level. Results The characters of ECG in PPB were： heart rate increased with the excessive pressure level; cardiac arrthymias, such as premature beat and conduction system block , occurred occasionally （totally 7.4% ）. The most exhibition form of ECG in PPB was P wave amplitude heighten, which enhanced 48.0% in 9.80 kPa PPB compared no excessive pressure （P〈0.01）. There was a decreasing trend in T wave amplitude with the excessive pressure increase, but only significant （P〈0.05） in 9.80 kPa . P-R interphase was shorten, and there was significant in all group （P〈0.05） compared with no PPB. Conclusions Since the sinal cardiac arrthymias and occasional premature beat disappeared when excessive pressure discharged, they have no effects on the estimation of the pilots PPB tolerance. For some exceptional ECG of pilots such as conduction system block, P wave wander rhythm and so on, we should give a accurate estimation according their blood pressure and subjective reaction.