特發性肺纖維化急性惡化－診斷、危險因子與機械通氣處置策略探討

Acute Exacerbation of Idiopathic Pulmonary Fibrosis: Diagnostic Criteria, Risk Factors and Strategy of Mechanical Ventilatory Support

呂家嘉(Chia-Chia Lu) ； 傅彬貴(Pin-Kuei Fu)

《內科學誌》 32卷1期 (2021/02) Pp. 8-19

https://doi.org/10.6314/JIMT.202102_32(1).02

摘要

特發性肺纖維化（idiopathic pulmonary fibrosis, IPF）是特發性間質性肺炎的最常見形式。特發性肺纖維化具有不同的臨床過程，從穩定無症狀到進行性呼吸衰竭或急性發作（Acute exacerbation, AE）。IPF-AE幾項重要的鑑別診斷，例如心衰竭和體液過多。國際工作組織在2016年提出IPF-AE的新定義，將其分為有觸發因素和特異性。在AE期間，觀察到瀰漫性肺泡損傷和喪失氣體交換，與急性呼吸窘迫症候群（acute respiratory distress syndrome, ARDS）患者相似。目前尚未有AE-IPF患者的最佳通氣策略的研究結論，仍建議採用低潮氣量和低驅動壓力的保護性通風策略。另外，由於肺泡及間質組織嚴重損害，不管肺纖維化的病因為何，皆極有可能發生呼吸器導致肺損傷（Ventilator-induced lung injury, VILI），因此引入了“彈性球肺（squishy ball）”的概念。討論了吐氣末正壓（PEEP）作用，提出了“肺部休息策略（lung resting strategy）”，而不是“維持肺擴張（open lung approach）”。透過本文獻回顧，我們希望提供臨床醫師關於AE-IPF的定義及診斷更新、AE-IPF之病理生理學表現、AE-IPF的危險因子以及AE-IPF進展至呼吸衰竭的呼吸治療策略，以增加對該疾病的認識。

關鍵字

特發性肺纖維化（Idiopathic pulmonary fibrosis） ； 急性惡化（Acute exacerbation） ； 呼吸治療（Respiratory therapy） ； 急性呼吸窘迫症（Acute respiratory distress syndrome） ； 肺休息策略（Lung resting strategy）

並列摘要

Idiopathic pulmonary fibrosis (IPF) is the most common form of idiopathic interstitial pneumonia. IPF has a heterogeneous clinical course, typically starting from an asymptomatic stable state that develops to a progressive respiratory failure or an acute exacerbation (AE). AE of IPF (AE-IPF) has several important differential diagnoses, like heart failure and volume overload. In 2016, the International Working Group project proposed new criteria for defining AE of IPF, dividing the condition into either (a) triggered AE or (b) idiopathic AE. During AE-IPF, diffuse alveolar damages occur with massive loss of aeration, similar to ARDS. Unlike ARDS, no consensus is reached regarding guidelines of ventilatory support and management strategies for AE-IPF patients admitted to the ICU. The protective ventilation strategy with low tidal volume and low driving pressure could be recommended to these patients, similar to ARDS patients. Due to severely impaired respiratory mechanics, the fibrotic lung is at high risk of developing ventilator-induced lung injuries, regardless of the fibrotic etiology. Hence, the concept of ＂squishy ball lung＂ has been introduced. The effect of positive end-expiratory pressure was discussed, ＂lung resting strategy＂ was proposed as opposed to the ＂open lung approach＂. Through this literature survey, we provided a comprehensive management of AE-IPF covering its latest diagnostic criteria, pathophysiology, risk factors, and the strategy of respiratory therapy.