Anesthetic Implications for Patients With Swyer-James Syndrome

Anesthetic Implications for Patients With Swyer-James Syndrome

ORIGINAL RESEARCH ARTICLE Anesthetic Implications for Patients With Swyer-James Syndrome Mark M Smith, MD,* David W Barbara, MD,* Benjamin C Smith, M...

273KB Sizes 0 Downloads 274 Views

ORIGINAL RESEARCH ARTICLE

Anesthetic Implications for Patients With Swyer-James Syndrome Mark M Smith, MD,* David W Barbara, MD,* Benjamin C Smith, MD,† Juraj Sprung, MD, PhD,* and Toby N Weingarten, MD* Objective: The aim of this study was to describe the anesthetic management and perioperative outcomes in patients with Swyer-James syndrome (SJS), a rare acquired pulmonary disorder caused by postinfectious bronchiolitis obliterans resulting in airway obstruction and focal areas of emphysema or bronchiectasis. Design: A retrospective computerized search of the medical records database at a large academic tertiary referral center was performed for patients with SJS from January 1, 2001 through July 31, 2012 who underwent procedures requiring anesthesia. A review of the perioperative course in the SJS patients as well as in those identified by a literature search was performed. Setting: Academic tertiary referral center, both inpatient and outpatient settings. Participants: Patients with a diagnosis of SJS. Interventions: No interventions were performed. Measurements and Main Results: The authors identified 4 patients with SJS who underwent 7 uneventful anesthetics

including one lung resection. Three patients were symptomatic preoperatively. The literature review identified 23 SJS patients who underwent lung resection for recurrent pulmonary symptoms. One patient developed hypoxemia during one-lung ventilation. Three patients had a prolonged hospital stay (≥10 days). All patients undergoing lung resection were young (≤42 years of age). Conclusion: Though SJS may be an incidental finding, these patients may have marked symptomatology, recurrent pulmonary infections, and pneumothoraces that may require lung resection. The patients tolerated anesthesia well. In severe SJS cases, pulmonary pathology and perioperative management strategies parallel that of patients with severe obstructive pulmonary disease. & 2013 Elsevier Inc. All rights reserved.

S

of SJS by a pulmonologist were included in the investigation. Patient records were reviewed for demographic variables, preoperative pulmonary status and symptoms, and other comorbid conditions. The surgical and anesthetic records were reviewed for details regarding the perioperative course. Hospital records were reviewed for postoperative events within 30 days with emphasis on respiratory complications. To review the perioperative complications in patients with SJS, the authors performed a literature search using an OVID-based search strategy of (1) PubMed (2001-present), (2) MEDLINE (2001-present), (3) EMBASE (2001-present), and (4) Web of Science (2001-present) under the following keywords: Swyer-James syndrome, Swyer-JamesMacLeod, unilateral hyperlucent lung syndrome, all limited to humans and English language. Bibliographies of identified published reports were searched for additional references. Identified reports of patients undergoing surgery were reviewed to identify perioperative complications.

wyer-James syndrome (SJS) is a rare acquired pulmonary disorder that develops secondary to infectious etiologies in early childhood.1 The condition manifests as a postinfectious bronchiolitis obliterans characterized with obstruction and emphysematous changes or bronchiectasis.2–7 These changes may lead to fibrosis in both the bronchioles and interalveolar septum, resulting in pulmonary capillary bed destruction.5,8 Clinical symptomology ranges from none in asymptomatic individuals with incidentally diagnostic findings on routine chest radiograph to severe symptoms, including dyspnea, recurrent pulmonary infections, hemoptysis, and pulmonary hypertension.4,9 The pulmonary changes associated with this disorder could pose challenges for anesthetic management. Because this is a very rare disorder, large-scale prospective studies are not feasible. To further assess the anesthesia outcomes in patients with SJS, the authors used the medical records database of a large academic referral center to identify SJS patients who underwent anesthesia, and then conducted a literature search of patients with SJS to review their perioperative course. METHODS After Institutional Review Board approval, a computerized search of the medical records database at a large academic tertiary referral center from January 1, 2001 through July 31, 2012 was conducted to identify patients with SJS who underwent anesthesia. The terms SwyerJames, unilateral emphysema, emphysema unilateral, hyperlucent lung, unilateral hyperlucent lung, and hyperlucent lobe were used to identify patients with this condition. Only patients with a confirmed diagnosis

KEY WORDS: Swyer-James syndrome, anesthesia, surgery, lung disease, MacLeod’s syndrome, unilateral hyperlucent lung syndrome

RESULTS

In the medical records database, 14 patients with SJS were identified, and all had provided authorization for search of

From the *Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, MN; and †Department of Radiology, Mayo Clinic College of Medicine, Rochester, MN. Address reprint requests to Toby N Weingarten, MD, Mayo Clinic College of Medicine, Department of Anesthesiology, 200 First Street SW, Rochester, MN 55905 E-mail: [email protected] © 2013 Elsevier Inc. All rights reserved. 1053-0770/2601-0001$36.00/0 http://dx.doi.org/10.1053/j.jvca.2013.03.039

Journal of Cardiothoracic and Vascular Anesthesia, Vol ], No ] (Month), 2013: pp ]]]–]]]

1

2

SMITH ET AL

Table 1. Patient Descriptions and Perioperative Findings in Patients with SJS Undergoing Anesthesia from the Medical Records Database at This Tertiary Referral Center Patient #/Sex

Patient 1 Female

Patient 2 Female

Procedure/ Age

1. a Craniotomy 36 yo 1. a Bronchoscopy 69 yo 2. Cesarean section 40 yo 2. Radius osteotomy 56 yo

Comorbidities

1. Meningioma, Seizures 1. None 2. None 2. None

Preoperative Symptoms

1. None 2. None

1. Dyspnea 2. Dyspnea

Patient 3 Male 1.

2. 1. 2. 3. 1. 2.

Perioperative Complications 1. Dilantin toxicity 2. None

Discharge POD Anesthesia Type Premedication Induction Medications Muscle Relaxant

Intraoperative Analgesic

Maintenance Anesthetic

Antiemetics Airway Management

Ventilator Mode Tidal Volume Peek Pressure FiO2 PEEP Intraoperative Hypoxemia (SaO2o88%) Monitors Extubation Location Postoperative Analgesia

POD 5 POD 3 General anesthesia Epidural anesthesia Midazolam None Thiopental None Succinylcholine, pancuronium 2. N/A 1. Fentanyl infusion 2. Lumbar epidural 1. 2. 1. 2. 1. 2. 1. 2. 1.

1. 2. 1. 2. 1. 2. 1. 2. 1. 2. 1. 2. 1. 2. 1. 2. 1. 2. 1. 2. 1. 2. 1.

2.

1. None 2. None

1. 2. 1. 2. 1. 2. 1. 2. 1. 2.

POD 0 POD 2 MACb General anesthesia Midazolam None None Thiopental None Succinylcholine

1. Topical lidocaine 2%

Fentanyl 2. Oxymorphone Nitrous oxide/fentanyl 1. N/A 2. Isoflurane infusion Epidural anesthesia 1. None Droperidol 2. Droperidol Droperidol 3. 1.OTT* OTT 10 L Oxygen via close 4. 2.OTT face mask 1. Spontaneous respirations AC 2. AC N/A 1. N/A 9mL/kg 2. 10 mL/kg N/A 1. N/A 32 cmH20 2. N/A N/A 1. 1.0 0.30 2. 0.40-0.60 N/A 1. N/A None 2. 5 cmH20 N/A 1. None None 2. None None 1. Standard ASA Standard ASA, RAL 2. Standard ASA, RAL, BIS Standard ASA 1. OR OR 2. OR N/A 1. None Codeine/ 2. Morphine PCA codeine/ acetaminophen acetaminophen acetaminophen Propoxyphene/ acetaminophen

a

Cardiac catheterization (radiofrequency ablation for atrial fibrillation) 41 yo Bronchoscopy 46 yo Atrial fibrillation Fibrosing mediastinitis Severe pulmonary hypertension Palpitations, dyspnea related to atrial fibrillation Hemoptysis, dyspnea

1. Pericardial effusion

2. 1. 2. 1. 2. 1. 2. 1. 2. 1. 2.

requiring pericardiocentesis None POD 5 POD 0 General anesthesia MACb Midazolam Midazolam Thiopental None None None

Patient 4 Female Right upper and middle lobe lobectomy 22 yo

Recurrent pneumonia Previous smoker

Hemoptysis

None Resected lung grew Mycobacterium avium complex POD 8 General anesthesia Midazolam Propofol Succinylcholine Vecuronium

1. Fentanyl 2. Fentanyl

Thoracic epidural

1. Isoflurane/nitrous oxide 2. Propofol

Isoflurane

1. 2. 1. 2.

Ondansetron Ondansetron OTT OTT*

Ondansetron

1. 2. 1. 2. 1. 2. 1. 2. 1. 2. 1. 2. 1. 2. 1. 2. 1. 2.

AC Spontaneous respirations NR N/A NR N/A 0.30 1.0 5 cmH20 N/A None None Standard ASA, RAL, BIS Standard ASA OR OR Fentanyl in PACU None

AC

Double-lumen OTT

6 mL/kg 22-28 cmH20 during OLV 1.0 during OLV 5 cm H20 None Standard ASA, RAL PACU Thoracic epidural Hydromorphone PCA Oxycodone

Abbreviations: yo, year old; POD, postoperative day; MAC, monitored anesthesia care; N/A, not applicable; OTT, Oral Tracheal Tube; AC, assist control; NR, not recorded; OLV, one-lung ventilation; ASA, American Society of Anesthesiologists; RAL, radial arterial line; BIS, bispectral index; PCA, patient controlled analgesia; PACU, postanesthesia care unit. a 1, 2 refer to first and second operation b MAC for bronchoscopy includes fiberoptic endotracheal intubation via bronchoscope after airway topicalization.

3

ANESTHETIC IMPLICATIONS WITH SWYER-JAMES

Table 2. Perioperative Characteristics in Patients with SJS Undergoing Surgery from the Literature Search Patient/Age at Surgery

Author 18

Surgical Procedure

Indication

Perioperative Complications

Discharge

Pneumonectomy

Hemoptysis Recurrent pneumonia

Not reported

Not reported

Thoracotomy with unilateral bronchial occlusion Thoracotomy with unilateral bronchial occlusion Thoracotomy with unilateral bronchial occlusion Thoracotomy with segmentectomy

Recurrent pneumonia

Not reported

POD 7

Recurrent pneumonia

Not reported

POD 8

Recurrent pneumonia

Not reported

POD 10

Not reported

Not reported

Not reported Not reported Not reported

Not reported Not reported Not reported

Koyama et al 200114

24 M 25 M 3 patients (age and sex not reported) 36 yo F

Chest pain Dyspnea on exertion Thoracotomy with segmentectomy Chest pain Thoracotomy with segmentectomy Dyspnea Thoracotomy with lobectomy Recurrent pneumonia

Thoracotomy with lobectomy

None

POD 15

Fregonese et al 200211

11 M

Right pneumonectomy

None

POD 30

Tasaki et al 200515 Inoue et al 200212

28 M 15 M

VATS lung volume reduction VATS Bullectomy, with chemical pleurodesis

Wolfe et al 1974

Vishnevsky et al 199017

5 patients (age and sex not reported) 38 F 42 F 23 M

Ohri et al 19935

Lucaya et al 19983

20 F

Marchevsky et al 20051

32 F

VATS Bullectomy, with chemical pleurodesis, and abrasion Right pneumonectomy

Sulaiman et al 20088

22 F

Thoracotomy with lobectomy

Kim et al 200813

5M

Thoracotomy with lobectomy and segmentectomy

Da Silva et al 20119

8M

Right pneumonectomy

Yekeler 201216

21 M

Thoracotomy with lobectomy

Dyspnea Recurrent pneumothorax Recurrent pneumonia Recurrent pneumonia Dyspnea hypoxemia Dyspnea on exertion Non-resolving pneumothorax

Recurrent pneumothorax Hyperinflation and nonfunctional lung lead to compression of normal lung Chest pain Recurrent pneumonia, Dyspnea Cyanosis Recurrent pneumonia Pulmonary hypertension Dyspnea Recurrent pneumonia Dyspnea Chest pain

None POD 5 Hypoxia requiring Not reported intermittent bilateral ventilation Unknown Not reported None

POD 5

Not reported

Not reported

Not reported

POD 7

Not reported

POD 6

Not reported

POD 7

Abbreviations: POD, postoperative day; M, male; F, female; VATS, video-assisted thoracic surgery.

their medical records.10 Of these 14 patients, 4 underwent a total of 7 anesthetics at this institution and will be referred to as group I (Table 1). Three of four patients had respiratory symptoms preoperatively. One patient had dyspnea on exertion, another had exertional dyspnea and hemoptysis, and a third patient had hemoptysis and recurrent pneumonias. Three of the procedures performed on these patients were related to the diagnosis of SJS. There were no major perioperative complications related to SJS. Postoperative complications were related to the procedure and were not related to pulmonary pathology. A comprehensive literature search identified 9 English language publications of the surgical management of patients

with SJS.1,8,9,11–16 Reference lists provided in these publications were searched, and an additional 4 reports discussing surgical management of SJS were identified.3,5,17,18 These publications reported a total of 23 patients, median age 23, range 5-42 years, referred to as group II (Table 2). Patients in all reported cases underwent thoracic surgeries that typically involved partial resection or pneumonectomy of the affected lung to treat dyspnea, recurrent pneumonia, and/or pneumothoraces. Only 1 patient in group II did not tolerate one-lung ventilation.12 No major postoperative complications were reported. Three reports described prolonged hospital stays (≥10 days)11,14,17 but did not elaborate on the reasons for these extended hospital stays.

4

SMITH ET AL

DISCUSSION

Patients with SJS frequently present with recurrent pneumonias, dyspnea, and pneumothoraces, necessitating thoracotomy to resect the affected lung tissue. Despite the underlying pulmonary pathology, evidence inferred from the limited number of published reports suggests that these patients tolerate anesthesia and surgery well. This can be explained by the fact that the affected lung tissue is relatively nonfunctional and contributes minimally to respiratory gas exchange. This is demonstrated in Figure 1, showing minimal tracer uptake in the affected lung during ventilation and undetectable tracer uptake during perfusion images. The remaining lung tissue, in the absence of additional coexisting pulmonary diseases, functions normally. Additionally, these patients typically are younger and devoid of other major comorbidities. SJS was first described by Swyer and James in a 6-year-old boy with recurrent pneumonia and translucency on chest radiography who underwent unilateral pneumonectomy.19 One year later, MacLeod reported a series of 9 patients with diminished breath sounds and radiographic translucency.20 Additional terminologies used to describe this condition include Swyer-James-Macleod syndrome, Macleod syndrome, unilateral hyperlucent lung syndrome, and unilateral emphysema. Distinction should be made between the acquired condition of SJS and congenital forms of unilateral emphysema or hyperlucent lung syndrome, as these are distinct diseases. The characteristic finding associated with SJS is a hyperlucency of 1 lung on chest radiography due to diminished pulmonary vascularity, along with the presence of air trapping in the terminal airways (Figure 2).13 The overall prevalence of SJS is estimated at 0.01%, but this probably is an underestimate because many asymptomatic patients are undiagnosed.11,13 This institution serves as a referral center for SJS patients, which can account for a higher predominance of cases with respiratory symptomology. The etiology of SJS is not understood completely but is felt to be an acquired form of bronchiolitis obliterans, which develops after infections with Mycoplasma pneumoniae, Bordetella pertussis, Mycobacterium tuberculosis, measles, influenza A, respiratory syncytial virus, adenovirus, or even toxic chemical inhalation.1–9,13,21 This terminal airway obstruction leads to distal emphysematous changes in the affected lobes.1–7 The inflammatory process can cause fibrosis in the bronchioles and interalveolar septum, which, in addition to chronic alveolar

Fig 2. Noncontrast axial image from expiratory chest CT demonstrates hyperlucency (air trapping) of a hypoplastic left lung with diminutive left-sided pulmonary arteries consistent with SwyerJames syndrome.

distention, leads to obliteration of the pulmonary capillary bed, decreased pulmonary blood flow, and arterial hypoplasia.5,8 The hyperlucency and abnormalities seen on pulmonary angiography, as well as ventilation/perfusion studies, are due to decreased pulmonary blood flow and pulmonary arterial hypoplasia (Figure 2).5,8,11,16 The disease typically is unilateral and may involve the entire lung, individual lobes, or select segments.9 There have been rare reports of bilateral lung involvement.9 A correlation exists in SJS between the presence of bronchiectasis and disease severity. Patients without bronchiectasis or those having cylindrical bronchiectasis (bronchi that show a regular outline without increased diameter ending squarely and abruptly) often are asymptomatic or have minimal symptoms.3,9,22 Conversely, patients with saccular bronchiectasis (bronchial dilatation increasing progressively toward the lung periphery with a ballooning outline appearance of the bronchus) have an increased frequency of pulmonary infections, more severe symptoms, and higher tendency for requiring surgery.3,22 These recurrent pulmonary infections often are related to atypical microorganisms such as Pseudomonas

Fig 1. Frontal planar images from Xe-133 ventilation scan (A) and Tc-99m MAA perfusion scan (B) demonstrate asymmetric decreased ventilation of a hypoplastic left lung without detectable left lung perfusion. Findings consistent with Swyer-James syndrome.

5

ANESTHETIC IMPLICATIONS WITH SWYER-JAMES

aeruginosa11 and Mycobacterium avium complex, as was the case in group I patient 4 (Table 1). SJS has a wide constellation of symptoms ranging from those who are asymptomatic to those with recurrent pulmonary infections, hemoptysis, and pulmonary hypertension. Most patients are managed conservatively; however, severe symptoms, recurrent infections resistant to medical management, and recurrent pneumothoraces are indications for resection.14,16,19 In one patient, lung volume reduction surgery was done to alleviate symptoms and improve pulmonary mechanics.15 The patients from this institution in group I tolerated anesthesia and surgery well. There were no perioperative complications discovered that were attributable to the disease. Patient 3 (Table 1) developed a pericardial effusion after radiofrequency ablation of atrial fibrillation and was the only patient who experienced a major complication, albeit a known complication of the primary procedure. In review of the patients reported in the literature in group II, Inoue et al12 described hypoxemia during single-lung ventilation, necessitating intermittent two-lung ventilation; however, it remains unknown as to whether hypoxemia in that patient could be attributed to his primary pulmonary dysfunction or one-lung ventilation. Of note, most studies mention uneventful postoperative courses but fail to disclose detailed information. Similarly, review of literature for SJS patients undergoing surgery did not identify other perioperative complications unique to this patient population.1,3,5,8,9,11–18 There is a wide variation in the length of postoperative hospitalization, ranging from 5-30 days, and the reasons for these extended hospital stays were not reported.11,14,17 Patients with SJS present several considerations for the anesthesiologist. Given the wide range in severity of lung involvement, a detailed history and physical examination, along with diagnostic testing, can aid in determination of an individual’s pulmonary function and remaining reserve. The unilateral decrease in ventilation with bronchiolar inflammation, air trapping, and eventual emphysematous changes may be accompanied by compensatory hypoperfusion of affected areas.5,9,17 In severe cases, the affected lung may lack perfusion.17 In fact, ventilation-perfusion imaging in severe cases reveals decreases in both perfusion and ventilation, with the perfusion impairments slightly exceeding that of ventilation, thereby resulting in mildly elevated ventilation-toperfusion ratios.4 This increased deadspace would be expected to have little clinical effect on uptake of inhaled anesthetics.

Despite the focal hyperlucency and unilateral emphysematous changes commonly noted on preoperative chest radiographs, pulmonary function testing in SJS patients undergoing thoracic surgery typically demonstrates reduced lung volumes without evidence of obstruction.5,9,15 Given the unilateral lung involvement in most SJS patients, intraoperative lung isolation for thoracic surgery generally is well tolerated. Again this likely is explained by the fact that the affected lung regions lack significant ventilation or perfusion and thus contribute sparingly if at all to gas exchange. Also, the remaining, unaffected lung tissue functions normally and can compensate for the affected lung portion, explaining why patients with this disease often are asymptomatic. Bronchiolar obstruction in the affected lung region can lead to overdistended terminal airways, increasing the risk of a pneumothorax with positive-pressure ventilation. Additionally, the use of nitrous oxide has the theoretic potential to cause alveolar rupture in areas of air trapping and also to worsen pneumothoraces.23 The individualized preoperative, intraoperative, and postoperative anesthetic care is dependent upon the disease severity, type of surgical procedure, and coexisting comorbidities. As is seen in the review of anesthesia in group I (Table 1), a wide range of anesthetic types were administered successfully to patients undergoing numerous surgical procedures. Regional and neuraxial anesthesia appear to be safe in patients with SJS. As with other respiratory disorders, caution should be used when performing techniques that could anesthetize the phrenic nerve(s) in patients with severe disease. Avoidance of large tidal volumes and high peak airway pressures during mechanical ventilation will help reduce the risk of iatrogenic pneumothorax. One-lung ventilation (OLV) was overall well tolerated in both group I and group II patients with the exception of 1 case of desaturation from the literature.12 Therefore, in SJS, anesthetic management should be individualized to cardiopulmonary function and, in severe cases, parallels that of patients with obstructive pulmonary disease. In conclusion, the SJS patients tolerated surgeries under general and neuraxial anesthesia without significant morbidity or mortality. Even though SJS can be asymptomatic, many patients have underlying pulmonary pathology; thus, a thorough preoperative assessment is prudent. Even though no patients in this review experienced perioperative respiratory complications, the potential of developing these perioperatively should be recognized, and appropriate preventative management strategies should be utilized.

REFERENCES 1. Marchevsky AM, Guintu R, Koss M, et al: Swyer-James (MacLeod) syndrome with placental transmogrification of the lung: A case report and review of the literature. Arch Pathol Lab Med 129: 686-689, 2005 2. Cumming GR, Macpherson RI, Chernick V: Unilateral hyperlucent lung syndrome in children. J Pediatr 78:250-260, 1971 3. Lucaya J, Gartner S, Garcia-Pena P, et al: Spectrum of manifestations of Swyer-James-MacLeod syndrome. J Comput Assist Tomogr 22:592-597, 1998 4. O'Dell CW, Taylor A, Higgins CB, et al: Ventilation-perfusion lung images in the Swyer-James syndrome. Radiology 121:423-426, 1976

5. Ohri SK, Rutty G, Fountain SW: Acquired segmental emphysema: The enlarging spectrum of Swyer-James/Macleod's syndrome. Ann Thorac Surg 56:120-124, 1993 6. Reid L, Simon G, Zorab PA, et al: The development of unilateral hypertransradiancy of the lung. Br J Dis Chest 61:190-192, 1967 7. Stokes D, Sigler A, Khouri NF, et al: Unilateral hyperlucent lung (Swyer-James syndrome) after severe Mycoplasma pneumoniae infection. Am Rev Respir Dis 117:145-152, 1978 8. Sulaiman A, Cavaille A, Vaunois B, et al: Swyer-James-MacLeod syndrome: Repeated chest drainages in a patient misdiagnosed with pneumothorax. Interact Cardiovasc Thorac Surg 8:482-484, 2009

6

9. da Silva PS, Lopes R, Neto HM: Swyer-James-MacLeod syndrome in a surgically treated child: A case report and brief literature review. J Pediatr Surg 47:e17-e22, 2012 10. Jacobsen SJ, Xia Z, Campion ME, et al: Potential effect of authorization bias on medical record research. Mayo Clin Proc 74: 330-338, 1999 11. Fregonese L, Girosi D, Battistini E, et al: Clinical, physiologic, and roentgenographic changes after pneumonectomy in a boy with Macleod/Swyer-James syndrome and bronchiectasis. Pediatr Pulmonol 34:412-416, 2002 12. Inoue M, Nakagawa K, Kameda M, et al: Video-assisted thoracoscopic bullectomy for spontaneous pneumothorax in a Swyer-James syndrome patient. Jpn J Thorac Cardiovasc Surg 50:439-442, 2002 13. Kim CK, Koh JY, Han YS, et al: Swyer-James Syndrome with finger clubbing after severe measles infection. Pediatr Int 50: 413-415, 2008 14. Koyama T, Osada H, Kitanaka Y, et al: Surgically treated SwyerJames syndrome. Jpn J Thorac Cardiovasc Surg 49:671-674, 2001 15. Tasaki A, Nakanishi R: Lung volume reduction surgery for a professional athlete with Swyer-James syndrome. Ann Thorac Surg 80: 342-344, 2005

SMITH ET AL

16. Yekeler E: A rare case of Swyer-James-Macleod syndrome and a new clinical presentation, acquired lobar emphysema. Ann Thorac Surg 93:e123-e125, 2012 17. Vishnevsky AA, Nikoladze GD: New approach to the surgical treatment of Swyer-James-MacLeod syndrome. Ann Thorac Surg 50: 103-104, 1990 18. Wolfe WG, Anderson RW, Sealy WC: Hyperlucent lung. Pathophysiology and surgical management. Ann Thorac Surg 18: 172-185, 1974 19. Swyer PR, James GC: A case of unilateral pulmonary emphysema. Thorax 8:133-136, 1953 20. Macleod WM: Abnormal transradiancy of one lung. Thorax 9: 147-153, 1954 21. Trimis G, Theodoridou M, Mostrou G, et al: Swyer-James (MacLeod's) syndrome following pertussis infection in an infant. Scand J Infect Dis 35:197-199, 2003 22. Reid LM: Reduction in bronchial subdivision in bronchiectasis. Thorax 5:233-247, 1950 23. Eger EI 2nd, Saidman LJ: Hazards of nitrous oxide anesthesia in bowel obstruction and pneumothorax. Anesthesiology 26:61-66, 1965