Laffey J G, Kavanagh B P
Department of Anaesthesia and Medical-Surgical Intensive Care Unit, Toronto General Hospital, University Health Network, University of Toronto, Ontario, Canada.
Lancet. 1999 Oct 9;354(9186):1283-6. doi: 10.1016/S0140-6736(99)02388-0.
Permissive hypercapnia (acceptance of raised concentrations of carbon dioxide in mechanically ventilated patients) may be associated with increased survival as a result of less ventilator-associated lung injury. Conversely, hypocapnia is associated with many acute illnesses (eg, asthma, systemic inflammatory response syndrome, pulmonary oedema), and is thought to reflect underlying hyperventilation. Accumulating clinical and basic scientific evidence points to an active role for carbon dioxide in organ injury, in which raised concentrations of carbon dioxide are protective, and low concentrations are injurious. We hypothesise that therapeutic hypercapnia might be tested in severely ill patients to see whether supplemental carbon dioxide could reduce the adverse effects of hypocapnia and promote the beneficial effects of hypercapnia. Such an approach could also expand our understanding of the pathogenesis of disorders in which hypocapnia is a constitutive element.
允许性高碳酸血症（即接受机械通气患者体内二氧化碳浓度升高）可能因减少呼吸机相关性肺损伤而与生存率提高相关。相反，低碳酸血症与许多急性疾病（如哮喘、全身炎症反应综合征、肺水肿）相关，并且被认为反映了潜在的过度通气。越来越多的临床和基础科学证据表明二氧化碳在器官损伤中发挥着积极作用，其中二氧化碳浓度升高具有保护作用，而低浓度则具有损伤作用。我们假设可以在重症患者中测试治疗性高碳酸血症，以观察补充二氧化碳是否可以减少低碳酸血症的不良影响并促进高碳酸血症的有益作用。这种方法还可以扩展我们对以低碳酸血症为构成要素的疾病发病机制的理解。
