A novel approach to resolve severe mediastinal and subcutaneous emphysema occurring in Pneumocystis jirovecii pneumonia using vacuum-assisted closure therapy

Introduction

This case report describes a case of severe subcutaneous and mediastinal emphysema without pneumothorax in a patient with Pneumocystis jirovecii pneumonia (PJP), which was treated with vacuum-assisted closure (VAC) therapy.

The occurrence of spontaneous pneumomediastinum in PJP is rare but has been described in several case reports.^1–10 Pneumomediastinum in these cases was usually related to intubation or lung function tests. A few case reports describe subcutaneous emphysema together with pneumomediastinum, although not as extensive as in our patient.^9,10 There are no reports of spontaneous subcutaneous emphysema without pneumothorax or pneumomediastinum in PJP. Subcutaneous emphysema often resolves spontaneously, but VAC therapy has been used in the treatment of subcutaneous emphysema after cardiothoracic surgery and in association with mechanical ventilation.^11–13 Also, “blow-hole” skin incisions have been used in the past to release air in severe subcutaneous emphysema.^14,15 Severe subcutaneous and mediastinal emphysema can be life threatening due to compression of the heart and lungs; therefore, it requires treatment if it does not resolve spontaneously or when it leads to circulatory problems. The VAC therapy used in this case report was initiated as a last resort treatment due to a lack of other options and no spontaneous improvement.

Case description

A 50-year-old male patient was admitted to our hospital with progressive dyspnea, cough, and cold sweats. He mentioned night sweating for a year and 15 kilograms weight loss. His medical history stated a human immunodeficiency virus (HIV) infection since 2003, with a double-sided pneumonia with Pneumocystis jirovecii (among other pathogens) at admittance, therefore diagnosed as acquired immunodeficiency syndrome (AIDS). Patient was treated with antiretroviral therapy with an undetectable viral load in 2012, but had stopped taking medication 1 year ago. He lived in a homeless shelter with his wife (who was also HIV positive); his children were accommodated elsewhere. There was no (intravenous) drug or alcohol use, and he had quit smoking 15 years ago. Physical examination on admission showed a non-acutely ill patient, tachypneic with an oxygen saturation of 88% on room air. His blood pressure was 130/80 mm Hg, heart rate 132 per minute, and temperature 38.2°C. Percussion of the lungs did not reveal any dullness, and at auscultation normal breath sounds were heard except for the left lower side. Other physical examination was unremarkable.

Relevant laboratory results on admission were hemoglobin 7.2 mmol/L, white blood cell count 6.6 × 10⁹/L, platelets 214 × 10⁹/L, and C-reactive protein (CRP) 64 mg/L. There was no renal or hepatic insufficiency. Immunology results were as follows: CD4: 0.039 × 10⁹/L, CD8: 1.2 × 10⁹/L, CD4/CD8 ratio: 0.033. A chest X-ray showed bilateral “cloudy” infiltrates.

The patient was treated according to the local sepsis protocol, with gentamicin 280 mg and amoxicillin/clavulanic acid 1200 mg intravenously in the emergency room. This was followed by cotrimoxazole (3 × 1920 mg) and prednisolone (2 × 40 mg) the next day for suspected PJP. Two days after admission, a bronchoscopy with bronchoalveolar lavage (BAL) was performed to confirm the diagnosis. Directly after this procedure, the patient became dyspneic, had low oxygen saturations (82%), and developed subcutaneous emphysema. Due to progressive respiratory insufficiency, endotracheal intubation and mechanical ventilation were necessary. Bronchoscopy-guided intubation was performed in the operating theater, which was uneventful. A computed tomography (CT) scan of the chest immediately after intubation showed subcutaneous and mediastinal emphysema without pneumothorax. Also, severe air bronchograms and bilateral infiltrations were seen. Patient was admitted to the intensive care unit (ICU) afterward.

During the (ventilatory) treatment on the ICU, the subcutaneous and mediastinal emphysema increased, resulting in swelling of the entire face, arms, and torso down to the scrotum (Figure 1). Several bronchoscopies were performed to exclude tracheal injury that could have occurred during the BAL, but no injury was visualized. Despite efforts to treat patient with lung protective ventilation, using low tidal volumes and low airway pressures, the emphysema continued to increase. A new CT scan was performed 1 week after admission to the ICU, showing severe subcutaneous and mediastinal emphysema (Figure 2). Treatment of the emphysema by skin incisions alone (“blow holes”) was considered but discarded due to the high HIV viral load (700,000 copies/mL) of the patient and the fear of viral spreading by blood spatters. Because of the severity and increase of the symptoms and no obvious tracheal injury (on subsequent bronchoscopies and CT scans), a search for other treatment options was performed. After elaborate consideration, it was decided to make two infraclavicular skin incisions and place VAC therapy on these incisions (ActiV.A.C., KCI Medical, –125 mm Hg; Figure 3). While the subcutaneous emphysema started to improve significantly, a gradual clinical improvement was seen in the first week. VAC therapy was ended 9 days after initiation. The subcutaneous emphysema continued to decrease after removal of the VAC therapy system.

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Figure 1.

Photograph of subcutaneous emphysema prior to VAC therapy (with permission).

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Figure 2.

Chest CT scan 1 week after admission to the ICU (with permission).

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Figure 3.

Photograph of VAC system in situ (with permission).

During his stay on the ICU, inflammatory markers decreased together with the pulmonary infiltrations on the chest X-ray, implying adequate treatment of the PJP. Patient was extubated after 17 days of mechanical ventilation, with a significant ICU-acquired weakness. Furthermore, dysphonia was reported, possibly caused by emphysema of the larynx. The patient was discharged to the general ward 25 days after admission to the ICU. Antiretroviral medicine was restarted, and patient was finally discharged to a medical rehabilitation center for further recovery.

Literature review

Research in three medical databases (PubMed, Embase, and Cochrane libraries) using the search (MeSH) terms “vacuum assisted closure therapy,” “negative pressure wound therapy,” “subcutaneous emphysema,” “mediastinal emphysema,” and “pneumothorax” in variable combinations revealed a total of 29 unique articles. After selecting on title, abstract, English language, and full text availability, six articles remained describing the use of VAC therapy in subcutaneous emphysema, pneumothorax, or pneumomediastinum.^{11,12,16–18} Byun et al. ¹¹ described four patients with pneumothorax and thoracic subcutaneous emphysema after cardiothoracic surgery, who were successfully treated with VAC therapy adjacent to chest tube drainage with a mean therapy duration of 3 days. The main improvement was already seen after 24 h. Negative pressure wound therapy (NPWT) was also used in a case of severe subcutaneous emphysema in a trauma patient, described by Mihanovic et al. ¹⁶ Sciortino et al. ¹⁷ described a patient after upper lobe bullectomy with a tension pneumothorax and severe subcutaneous emphysema, which drastically improved within 48 h after initiating NPWT, where chest tube drainage alone had failed. Son et al. described the use of NPWT in 10 patients on mechanical ventilation, expressing their concern of using “blow holes” alone in mechanical ventilation as this might not release enough air. The duration of NPWT in patients on mechanical ventilation was longer than described previously by Byun et al. with a mean of 7.5 days (±5.1 days). ¹¹ Towe et al. ¹² reported a patient with persistent subcutaneous emphysema after a lobectomy, despite adequate chest tube drainage. They claim to be the first ones to describe bilateral skin incisions. The duration of their therapy was 8 days until full recovery. The last case series was described in a conference abstract by Hristova et al. ¹⁴ where six patients underwent NPWT in addition to chest tube drainage, with either unilateral or bilateral “blow hole” incisions and always using unilateral NPWT. Most patients showed significant improvement of subcutaneous emphysema within 24 h.

Discussion

Severe subcutaneous emphysema is a condition that needs adequate treatment, because of the danger of impaired blood supply to the skin, muscles, and other tissues. Furthermore, mediastinal emphysema can lead to reduced expansion of the lungs leading to respiratory insufficiency, damage to compressed lungs, and an altered blood flow especially in tension pneumomediastinum.^11,19 It can even lead to cardiac compression mimicking cardiac tamponade. ¹⁹ When the emphysema is caused by a pneumothorax, this is usually treated by chest tube drainage. Literature search does reveal the use of VAC therapy in cases of subcutaneous emphysema but mainly used in addition to chest tube drainage in pneumothorax.^12,14,15,17 It is questionable whether this therapy has an advantage to chest tube drainage alone, which is frequently used after thoracic surgery and is successful in most cases. A review into the use of other therapies for persistent subcutaneous emphysema does mention the use of “blow holes” or subcutaneous tube drainage, but they create a lot of work with frequent change of wound dressings and a risk of clotting the tubes.^13,20 A disadvantage of VAC therapy can be discomfort of the patient when changing wound dressings, skin damage due to the suctioning, and scars due to the incisions.

Subcutaneous emphysema usually dissolves spontaneously in the course of several days to weeks, depending on its severity. ⁶ It is possible that the improvement seen in our patient was the natural course of the illness and thus had been self-limiting. However, since the subcutaneous emphysema started to improve significantly after applying the VAC therapy, this improvement was more likely to be a result of the VAC therapy.

Further clinical research into the use of VAC therapy in severe subcutaneous emphysema (spontaneous or otherwise not caused by pneumothorax) is essential, but options are limited due to the small number of eligible patients. This treatment option, however, should be considered in such cases.

Conclusion

Severe mediastinal and subcutaneous emphysema without pneumothorax in a ventilated HIV-positive patient with PJP can be treated using VAC therapy on (infraclavicular) skin incisions.