Furukawa Kento, Asai Yuichiro, Nagahisa Yuta, Takano Keiichiro, Chiba Hirofumi
Department of Respiratory Medicine and Allergology, Sapporo Medical University, Sapporo, JPN.
Cureus. 2024 Jul 11;16(7):e64352. doi: 10.7759/cureus.64352. eCollection 2024 Jul.
Negative-pressure pulmonary edema (NPPE) arises from excessive inspiratory effort due to upper airway obstruction, often associated with postoperative laryngospasm and upper airway infections like epiglottitis. We present a case of NPPE during bronchoscopy. A 45-year-old female patient, who was undergoing bronchoscopy for interstitial pneumonia evaluation, was examined using a tracheal tube with a 7.5 mm internal diameter and a bronchoscope with a 5.9 mm external diameter. The patient's respiratory condition gradually worsened after intubation. We continued with the examination, supplying approximately 5 L/min of oxygen through the intubation tube. We performed an alveolar lavage, and the recovered fluid gradually turned pale and bloody. After the examination, the patient continued to expectorate pink and frothy sputum and prolonged respiratory failure. Chest radiography revealed new extensive bilateral infiltrates. We ruled out cardiogenic causes through clinical examination, electrocardiogram (ECG), and transthoracic echocardiography. As a result, we suspected that temporary upper airway obstruction during bronchoscopy led to NPPE. Applying continuous positive airway pressure (CPAP) quickly improved the pulmonary edema. The risk of NPPE during bronchoscopy needs to be acknowledged, especially when using larger bronchoscopes and smaller tracheal tubes.
负压性肺水肿（NPPE）源于上气道梗阻导致的过度吸气用力，常与术后喉痉挛及会厌炎等上气道感染相关。我们报告一例支气管镜检查期间发生NPPE的病例。一名45岁女性患者因评估间质性肺炎而接受支气管镜检查，使用内径7.5 mm的气管导管和外径5.9 mm的支气管镜进行检查。插管后患者的呼吸状况逐渐恶化。我们继续检查，通过插管以约5 L/分钟的流量供氧。我们进行了肺泡灌洗，回收的液体逐渐变为淡血性。检查后，患者持续咳出粉红色泡沫痰并出现长时间呼吸衰竭。胸部X线检查显示双肺出现新的广泛浸润。我们通过临床检查、心电图（ECG）和经胸超声心动图排除了心源性病因。因此，我们怀疑支气管镜检查期间的临时上气道梗阻导致了NPPE。应用持续气道正压通气（CPAP）迅速改善了肺水肿。支气管镜检查期间发生NPPE的风险需要引起重视，尤其是在使用较大支气管镜和较小气管导管时。
