Poggi Roberta, Appendini Lorenzo, Polese Guido, Colombo Roberto, Donner Claudio F, Rossi Andrea
Respiratory Division, Ospedali Riuniti, L.go Barozzi, 1, 24128 Bergamo, Italy.
Respir Med. 2006 Jun;100(6):972-9. doi: 10.1016/j.rmed.2005.10.007. Epub 2005 Nov 21.
It has been shown that upper limbs activity increases the respiratory workload in patients with chronic respiratory failure (CRF). The object of the present study was to investigate whether, in these patients: (i) noninvasive positive pressure ventilation (NPPV) could sustain the inspiratory muscles to meet the greater ventilatory demand during upper limbs activity with the arm elevation test (AE); (ii) proportional assist ventilation (PAV) might be superior to pressure support ventilation (PSV) during AE, because of its potential more adaptable response to sudden changes in the ventilatory pattern.
The study was performed in the pulmonary function laboratory of the Pulmonary Division in Verona General Hospital, Verona, Italy. We studied 8 male patients with CRF due to chronic obstructive pulmonary disease (COPD). Each patient received 2 treatment in random order with a crossover design: spontaneous breathing (SB), SB with AE, either PSV or PAV without and with AE, SB without and with AE, either PSV or PAV without and with AE. We measured: lung function tests, lung mechanics, ventilatory pattern and diaphragmatic effort (pressure time product, PTP(di)).
(i) AE increases minute ventilation (+14%) and PTP(di) (+64%); (ii) ventilatory support, both with PSV and PAV unloads the diaphragm both at rest (PTP(di) -77% and -54%, respectively) and during arm elevation (PTP(di) -54% and -44%, respectively).
PAV and PSV unloads the diaphragm in patients with CRF due to COPD both during SB and AE; PAV can be more efficient than PSV in assisting the diaphragm during AE in producing a greater level of minute ventilation for a similar rise in PTP(di) compared to PSV. Noninvasive ventilatory support should be considered in rehabilitation programs for training of upper limbs activity.
研究表明，慢性呼吸衰竭（CRF）患者上肢活动会增加呼吸负荷。本研究的目的是调查在这些患者中：（i）无创正压通气（NPPV）能否通过手臂抬高试验（AE）维持吸气肌以满足上肢活动期间更大的通气需求；（ii）比例辅助通气（PAV）在AE期间是否可能优于压力支持通气（PSV），因为它对通气模式突然变化的潜在适应性更强。
该研究在意大利维罗纳综合医院肺病科的肺功能实验室进行。我们研究了8名因慢性阻塞性肺疾病（COPD）导致CRF的男性患者。每位患者采用交叉设计按随机顺序接受2种治疗：自主呼吸（SB）、伴有AE的SB、不伴有和伴有AE的PSV或PAV、不伴有和伴有AE的SB、不伴有和伴有AE的PSV或PAV。我们测量了：肺功能测试、肺力学、通气模式和膈肌做功（压力时间乘积，PTP(di)）。
（i）AE使分钟通气量增加（+14%），PTP(di)增加（+64%）；（ii）PSV和PAV通气支持在静息时（PTP(di)分别降低77%和54%）和手臂抬高期间（PTP(di)分别降低54%和44%）均减轻了膈肌负荷。
对于因COPD导致CRF的患者，PAV和PSV在SB和AE期间均减轻了膈肌负荷；与PSV相比，在AE期间，PAV在辅助膈肌产生更高水平的分钟通气量方面可能比PSV更有效，而PTP(di)升高程度相似。在针对上肢活动训练的康复计划中应考虑无创通气支持。
