Background
Bullectomy is the surgical removal of a bulla, which is a dilated air space in the lung parenchyma measuring more than 1 cm. [1] A bulla that occupies more than 30% of the hemithorax is referred to as a giant bulla. The most common cause of a lung bulla is chronic obstructive pulmonary disease. Other conditions associated with lung bullae are alpha-1 antitrypsin deficiency, Marfan syndrome, Ehler-Danlos syndrome, cocaine smoking, sarcoidosis, HIV infection, coronavirus disease 2019 (COVID-19) pneumonia, and intravenous (IV) drug abuse.
Bullae increase physiologic dead space and compress surrounding normal lung tissue. Giant bullae also exert pressure on the diaphragm and effect its contractility. The natural history of bullae is one of enlargement causing worsening of dyspnea; however, the rate of expansion is unpredictable. The clinical course of a giant bulla can be complicated by a pneumothorax and fluid accumulation within the bulla. [2]
Indications
Patient selection is one of the most important aspects of a successful bullectomy. [1] The most common indications for bullectomy include the following [3, 4, 5] :
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Severe dyspnea due to a giant bulla (ie, one occupying 30% or more of the hemithorax)
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Spontaneous secondary pneumothorax
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Pain
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Repeated infection
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Hemoptysis
Some authors also recommend surgery for bullae that are increasing in size on serial chest radiographs, as well as lesions occupying more than 50% of the hemithorax, even if the patient is asymptomatic. [4, 5]
Contraindications
Contraindications for bullectomy include the following:
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Significant comorbid conditions
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Poorly defined bullae on chest imaging
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Pulmonary hypertension
Forced expiratory volume in 1 second (FEV1) that is less than 35%, hypercapnia, cor pulmonale, and carbon monoxide diffusing capacity less than 40% are associated with an increased risk of surgical intervention. [6]
An increased risk of surgery exists with older age, but advanced age is not a contraindication. [7]
Technical Considerations
Complication prevention
Careful patient selection is the cornerstone of efforts to minimize patient mortality and morbidity. Tenets of complication prevention include the following:
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Early extubation, which minimizes the duration of positive-pressure ventilation and the risk of barotrauma associated with it [8]
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Maintenance of low intraoperative tidal volumes, which minimizes barotrauma to the nonoperative lung during surgery
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Minimal intraoperative fluid resuscitation and postoperative use of fluids, which minimize the risk of pulmonary edema and hypoxemia
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Pulmonary toileting in the early postoperative period
Outcomes
After bullectomy, surrounding healthy lung tissue expands, and chest mechanics improve by virtue of the remodeling of the thorax and diaphragm. Symptomatic improvement (dyspnea, exercise capacity, need for oxygen) and functional improvement occur. [9, 10, 11, 12, 13, 14, 15, 16]
The greatest benefit is seen in patients with large bullae accompanied by crowding of adjacent structures, upper-lobe predominance, and minimal underlying emphysema. [17]
Preoperative bulla size is the most important determinant of improvement in ventilatory capacity after bullectomy. [18]
Maximal benefit is noted in the first year after surgery. The improvements in symptoms and lung parameters decline a few years after surgery, but the patient's condition remains better than it was in the period before surgical treatment. [11, 12, 13, 16]
Pulmonary rehabilitation and smoking cessation are important in the management of these patients. Decline of lung function after surgery is less in those patients who stopped smoking than in those who continue to smoke.
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Computed tomography scan of chest showing bulla in left lung. Image courtesy of Richard Lazzaro, MD, New York Methodist Hospital.
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Flattened bulla. Image courtesy of Richard Lazzaro, MD, New York Methodist Hospital.
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Surgical field showing multiple bullae. Image courtesy of Richard Lazzaro, MD, New York Methodist Hospital.
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Surgical field showing bullae. Image courtesy of Richard Lazzaro, MD, New York Methodist Hospital.
