Marraro Giuseppe A
Pediatric Intensive Care Unit, Fatebenefratelli and Ophthalmiatric Hospital, Milan, Italy.
Pediatr Crit Care Med. 2003 Jan;4(1):8-20. doi: 10.1097/00130478-200301000-00003.
The recognition that alveolar overdistension rather than peak inspiratory airway pressure is the primary determinant of lung injury has shifted our understanding of the pathogenesis of ventilator-induced side effects. In this review, contemporary ventilatory methods, supportive treatments, and future developments relevant to pediatric critical care are reviewed.
A strategy combining recruitment maneuvers, low-tidal volume, and higher positive end-expiratory pressure (PEEP) decreases barotrauma and volutrauma. Given that appropriate tidal volumes are critical in determining adequate alveolar ventilation and avoiding lung injury, volume-control ventilation with high PEEP levels has been proposed as the preferable protective ventilatory mode. Pressure-related volume control ventilation and high-frequency oscillatory ventilation (HFOV) have taken on an important role as protective lung strategies. Further data are required in the treatment of children, confirming the preliminary results in specific lung pathologies. Spontaneous breathing supported artificially during inspiration (pressure support ventilation) is widely used to maintain or reactivate spontaneous breathing and to avoid hemodynamic variation. Volume support ventilation reduces the need for manual adaptation to maintain stable tidal and minute volume and can be useful in weaning. Prone positioning and permissive hypercapnia have taken on an important role in the treatment of patients undergoing artificial ventilation. Surfactant and nitric oxide have been proposed in specific lung pathologies to facilitate ventilation and gas exchange and to reduce inspired oxygen concentration. Investigation of lung ventilation using a liquid instead of gas has opened new vistas on several lung pathologies with high mortality rates.
The conviction emerges that the best ventilatory treatment may be obtained by applying a combination of types of ventilation and supportive treatments as outlined above. Early treatment is important for the overall positive final result. Lung recruitment maneuvers followed by maintaining an open lung favor rapid resolution of pathology and reduce side effects.
The methods proposed require confirmation through large controlled clinical trials that can assess the efficacy reported in pilot studies and case reports and define the optimal method(s) to treat individual pathologies in the various pediatric age groups.
认识到肺泡过度扩张而非吸气峰压是肺损伤的主要决定因素,这改变了我们对呼吸机诱导副作用发病机制的理解。在本综述中,对与儿科重症监护相关的当代通气方法、支持性治疗及未来发展进行了综述。
将肺复张手法、小潮气量和较高呼气末正压(PEEP)相结合的策略可减少气压伤和容积伤。鉴于合适的潮气量对于确定足够的肺泡通气及避免肺损伤至关重要,已提出采用高PEEP水平的容量控制通气作为更可取的保护性通气模式。压力相关容量控制通气和高频振荡通气(HFOV)已成为重要的肺保护策略。在儿童治疗中还需要更多数据,以证实特定肺部疾病的初步结果。吸气时人工支持的自主呼吸(压力支持通气)被广泛用于维持或恢复自主呼吸,并避免血流动力学变化。容量支持通气减少了手动调整以维持稳定潮气量和分钟通气量的需求,并且在撤机过程中可能有用。俯卧位通气和允许性高碳酸血症在接受人工通气的患者治疗中发挥了重要作用。在特定肺部疾病中,已提出使用表面活性剂和一氧化氮来促进通气和气体交换,并降低吸入氧浓度。使用液体而非气体进行肺通气的研究为几种高死亡率的肺部疾病开辟了新视野。
人们坚信,通过应用上述多种通气类型和支持性治疗的组合可获得最佳通气治疗效果。早期治疗对于总体良好的最终结果很重要。肺复张手法后维持肺开放有利于病变快速消退并减少副作用。
所提出的方法需要通过大型对照临床试验来证实,这些试验能够评估初步研究和病例报告中报道的疗效,并确定治疗不同儿科年龄组个体疾病的最佳方法。