varied between 31 and 38 cm of H2O. He maintained a normal arterial blood PH during most of his admission. On hospital day 11, the patient sud- denly became hypotensive and bradycardic requiring fluid boluses and vasopressor support with nor-epinephrine. Chest tube was noted to be functioning adequately. CXR did not reveal any acute changes. Soon thereafter, he went into asystole and CPR/ ACLS (cardio-pulmonary resuscitation/ advanced cardiac life support) was initi- ated immediately. Unfortunately, he died in cardiac arrest. DISCUSSION ABPF is a communication between the pleural space and the bronchial tree. Al- though rare, BPFs are associated with high morbidity and mortality. Postoperative complication of pulmonary resection is the most common cause, followed by necrotic lung complicating infection, chemotherapy or radiotherapy (for lung cancer), and per- sistent spontaneous pneumothorax. Less common risk factors include ARDS, chest
Figure B: Computed tomography scan chest (axial reconstruction) showing 30 mm large bronchopleural fistula (arrow).
was placed, and a 12 French chest tube (placed earlier) was removed. Repeat CXR showed improved reexpansion of right lung. On hospital day four, he came off of vasopressor sup- port and was started on furosemide drip to keep negative fluid balance in view of severe ARDS. Later that day, the patient developed respiratory distress with O2 sats of 71% and respiratory rate of high 40s. He was once again started on cisatracurium, and his oxygenation improvedmarginally. A large air-leak (more than previously noted during past three days) was noted from the chest tube. A cardiothoracic surgery team was consulted for concern of development of bronchopleural fistula. On hospital day five, a CT chest scan was repeated, which revealed a large right-sided BPF (Figure B), explain- ing the persistent large air-leak. The BPF measured 30 mm in length, a very rare occurrence. The CT chest scan was also significant for right-sided subcutaneous emphysema and residual pneumothorax (Figure B). The location of BPF was not suggestive of an iatrogenic etiology fromRIJ central line placement. Also, absence of BPF on previous CT scan from day three makes ARDS the most likely cause of the development of BPF in this case. A cardiothoracic surgery team recommended conservative management in view of patient’s critical illness. On hospital day six, cisatracurium was discontinued after 48 hours. Throughout his ICU stay, he required high FiO2 ranging between 70%-100% most of the time. His ABG consistently showed PaO2/FiO2 of <100. His end-inspiratory pressures
trauma, invasive chest procedures (including central line placements), tuberculosis, and serious co-morbid illness(s). 2 BPF in the setting of ARDS is most likely either a result of chest trauma or ventilator-induced lung injury from rupture of overdistended alveolus. The ventilator strategy of ARDS, directed to alveolar recruitment, conflicts the best management of BPF, which requires minimization of airway pressure to decrease the air leak. 2,4,5 The incidence of barotrauma inmechanically ventilated patients with ARDS varies between 0% and 49%, and cor- relates strongly with end-inspiratory pressure (Pplat), with a high incidence above 35 cm of H2O. With compliance, there is a high incidence below 30 ml/cm H2O. Clinical studies maintaining Pplat lower than 35 cm of H2O found no apparent relationship between ventilatory parameters and pneumothorax. Analysis of the literature suggests a correlation between patients receiving mechanical ventila- tion and Pplat levels exceeding 35 cm of H2O. 6 The clinical presentation is variable. It can rarely pres- ent acutely as life-threatening tension pneumothorax. Other presentations include persistent air-leak in the setting of an appropriately placed chest tube, fever, productive cough, and new or increasing air fluid levels seen on the chest radiograph in the pleural space. 2 Suspicion of BPF is usually raised after persistent large air-leak noted from chest tube. Standard and thin-section CTs are useful in the diagnosis and management of periph- eral BPFs. 7 A peripheral BPF can be localized with MDCT (multi- detector row computed tomography) if there is a distinct
J La State Med Soc VOL 166 November/December 2014 259
Made with FlippingBook - Online catalogs