[Evaluation of rounded atelectasis induced by exposure to asbestos]

We encountered 19 patients of rounded atelectasis induced by exposure to asbestos from 2000 to 2007. All patients were men whose ages arranged from 60 to 89 years with a mean of 74.2 years. Twenty rounded atelectasis were present in the right lung and 5 in the left lung. Five patients had 2 rounded atelectasis. In 21 rounded atelectasis were found in Segment 10 and while other 2 found in S1 and each in S5 and 9. Eleven patients were diagnosed with no symptoms through medical examinations. Other 8 patients complained of dyspnea, chest pain and cough. Thirteen patients complicated with benign asbestos pleurisy and only 3 patients accompanied asbestosis. Eighteen patients (95%) displayed pleural plaques and 15 patients with calcified plaques. Ten patients had been exposed to asbestos in the shipyards and 4 in construction works and other 5 patients had also exposed by occupational exposure to asbestos. The mean period of exposure to asbestos was 26.6 years and the mean latency periods from the first asbestos exposure to the diagnosis of rounded atelectasis were 51.6 years. An autopsied patient had 18,100 asbestos bodies per 1 g of dry lung tissue which meant the heavy asbestos exposure. High incidence of pleural plaques and long period of latency from the first exposure to the appearance of rounded atelectasis in this study suggested that rounded atelectasis might appear less high-dose exposure to asbestos than former patients who were reported 6 years ago.

[Respiratory morbidity after pulmonary resection; prevention and treatment of atelectasis and pneumonia]

A respiratory morbidity such as atelectasis or pneumonia is possible to be predicted by calculated postoperative pulmonary function. The predicted postoperative 1 second forced expiratory volume (FEV1.0) is exclusively useful for predicting morbidity, but not for predicting mortality. The exercise capacity is a crucial parameter to predict survival. Thus, both parameters are helpful to make strategies for perioperative management. A prophylactic tracheostomy, a timely traheostomy and a timely bronchoscopy are applied by these parameters to treat postopeartive respiratory complications such as atelectasis or pneumonia.

A rare cause of persistent atelectasis in childhood: mucoepidermoid carcinoma

A 12-year-old boy presented to our clinic with recurrent lower respiratory tract symptoms that are wheezing, cough, bronchopneumonia, and fever and with a diagnosis of bacterial endocarditis. Physical examination revealed that breath sounds diminished in the left lower lobe. Because cardiac sounds and echocardiography were normal bacterial endocarditis was excluded. Chest radiograph and computerized tomography scan showed a left lower lobe atelectasis and consolidation. Despite medical therapy including antibiotics, bronchodilator etc, atelectasis persisted. Fiberoptic flexible bronchoscopy (FFB) revealed a tumor that totally obstructed the left lower lobe bronchus. Open lung biopsy revealed a low-grade mucoepidermoid carcinoma. Left lower lung lobectomy was performed. The patient is in good condition 12 months after the operation. We proposed that FFB should be performed earlier in patients with recurrent lower respiratory symptoms who have persistent atelectasis or unifocal infiltration.

Pulmonary atelectasis in children anesthetized for cardiothoracic MR: evaluation of risk factors

PURPOSE

To systematically assess the frequency and risk factors for atelectasis in children anesthetized for cardiothoracic magnetic resonance (MR).

MATERIALS AND METHODS

We retrospectively identified 58 consecutive children (age range, 6 days to 21 years) who underwent cardiothoracic MR from January 2001 to December 2004 whose imaging and medical charts were available. One certificate of added qualification pediatric radiologist and 1 of 2 cardiothoracic radiologists, in consensus, evaluated the first and last set of axial images. Images were evaluated for cardiac, vascular and tracheobronchial abnormalities, and degree of atelectasis. Atelectasis was considered significant if the equivalent of 3 or more segments were involved. Patients received 1 or more of 7 anesthetic medications (n = 27), chloral hydrate alone (n = 4), or required no anesthesia (n = 27).

RESULTS

Significant atelectasis developed only in those receiving anesthetic medications. Thirty-seven percent (10/27) of anesthetized children developed significant atelectasis in the first and/or last axial sequence. In 90% (9 /10) of patients, it developed in the first axial sequence. Strong risk factors were age younger than 1 year (80%, 8/10, P = 0.029) and MR evidence of tracheobronchial narrowing (50%, 5/10, P = 0.008). In patients with vascular ring, there was a trend toward significance (40%, 4/10, P = 0.09). None of the anesthesia factors were significant, including ventilation mode, anesthesia duration, or American Society of Anesthesiology risk (all P > 0.1).

CONCLUSIONS

Atelectasis may occur shortly after induction of anesthesia in children younger than 1 year of age or with tracheobronchial narrowing when anesthetized for cardiothoracic MR.

Effect of low tidal volume ventilation on atelectasis in patients during general anesthesia: a computed tomographic scan

STUDY OBJECTIVE

To determine whether low tidal ventilation in patients without lung injury results in an increase in the amount of atelectasis and a further impairment of gas exchange during general anesthesia.

DESIGN

Randomized, single-blind study.

SETTING

University hospital.

PATIENTS

16 adult, ASA physical status I and II patients, who were scheduled for elective excision of intracranial lesion.

INTERVENTIONS

Patients were randomly allocated to one of two groups: traditional tidal volume (V(T)) ventilation group (V(T), 10 mL/kg) and low V(T) ventilation group (V(T), 6 mL/kg) after the first computed tomographic (CT) scan.

MEASUREMENTS AND MAIN RESULTS

Atelectasis, as determined by CT and arterial blood gas analysis, was measured before induction, after tracheal intubation, and at the end of operation. After tracheal intubation, CT scan showed atelectasis in both groups. The mean atelectasis area was 4.25 +/- 2.05 cm(2) (3.32% +/- 1.94%) in the traditional V(T) ventilation group and 5.56 +/- 3.21 cm(2) (4.19% +/- 2.31%) in the low V(T) ventilation group. At the end of operation, there was no significant increase in the amount of atelectasis within the two groups. Arterial blood gas analysis showed no differences after tracheal intubation or at the end of operation in either group.

CONCLUSION

Ventilation using low V(T)s does not cause more pulmonary collapse than mechanical ventilation using standard V(T)s.

Efficacy and safety of nebulized recombinant human DNase as rescue treatment for persistent atelectasis in newborns: case-series

AIM

To evaluate the efficacy and safety of using recombinant human DNase (rhDNase) in diminishing persistent atelectasis unresponsive to conventional treatment and mucus plugging in newborns with insufficient ability to clear thick and purulent airway secretions.

METHODS

Twelve newborns (10 preterms), who did not respond to conventional methods, received rhDNase nebulized therapy at a dose of 1.25 mg over a 15-minute period, twice a day (2 hours between the doses) for up to 3 days. The application of the drug was continued for up to 3 days or until the improvement of atelectasis. After a-three-day therapy, if atelectasis did not improve, a single dose (1.25 mg) of the same drug in liquid form was administered endotracheally. Clinical (respiration rate, requirement for oxygen concentration) and radiological response (chest x-ray scoring), duration of the treatment, recurrence of atelectasis and requirement for additional therapy were evaluated.

RESULTS

Ten out of 12 patients showed rapid clinical and radiological improvement after nebulized treatment. Two patients who did not respond to the three-day regimen received a single dose of the drug endotracheally and both recovered completely. Six patients did not require completion of three day regimen for radiological recovery. Chest x-ray scores and respiratory parameters showed significant improvement after the treatment. The respective median (range) values before and after treatment were 4 (1-5) and 0 (0-4) points for chest x-ray scores, 66 (60-78) and 49 (44-64) breaths/min for respiratory rates, and 45% (35-64) and 30% (21-40) for oxygen requirement. Comparison of pCO(2) before (median, 56 mm Hg; range, 46-64) and after treatment (median, 41 mm Hg; range 38-58) in 7 patients showed significant improvement.

CONCLUSION

In a large series of newborns to receive rhDNase and we demonstrated the usefulness of rhDNase as a mucolytic agent in treating newborns with persistent atelectasis who do not respond to other treatments.

Pleuropulmonary blastoma, a distinctive neoplasm of childhood: report of three cases

BACKGROUND

Pleuropulmonary blastoma (PPB) is a rare, aggressive dysontogenetic neoplasm affecting children. It was identified as a distinct entity by Manivel in 1988 and later subdivided into three types on the basis of the histological pattern, with increasing malignancy from type I (cystic) through type II (solid/cystic) to type III (solid).

OBJECTIVE

To report on the imaging findings, clinical presentation, and differential diagnosis, mainly cystic malformations.

MATERIALS AND METHODS

We evaluated three children, age 2-4 years, with PPB.

RESULTS

One patient presented with unresolving pneumothorax and a multicystic mass, another with a mixed fluid/solid lesion, and the last with a solid heterogeneous mass.

CONCLUSION

Despite its rarity, PPB should be considered in the evaluation of cystic or solid masses in children with respiratory distress. Plain film radiography alone is unable to distinguish between PPB and cystic malformations. CT represents the gold standard, although MRI can show the imaging features of solid enhancing nodules inside fluid-filled cavities, a mass causing lung compression, mediastinal shift, frequent pleural effusion, and no chest wall invasion. No preoperative imaging can reliably differentiate between congenital cystic lesions and PPB type I.

Adverse effect of complete thoracic evacuation during chronic pneumothorax in a dog

OBJECTIVE

To describe an unusual response to evacuation of a chronic pneumothorax in a dog.

CASE

Resolution of a pneumothorax is usually associated with lung expansion and a marked improvement in pulmonary function. In the case presented here, evacuation of a chronic pneumothorax improved oxygenation, but markedly impaired ventilation.

CLINICAL RELEVANCE

This is a previously unreported complication associated with the treatment of pneumothorax in dogs. It suggests that in some cases of chronic pneumothorax, total evacuation of the pleural air pocket may improve oxygenation but ventilation deteriorates and increases PCO2, causing further complications.

Pulmonary atelectasis manifested after induction of anesthesia: a contribution of sinobronchial syndrome?

A 31-year-old man underwent general anesthesia for sinus surgery. Anesthesia was induced with midazolam and butorphanol, and an endotracheal tube was orally placed with a bronchoscope, due to difficulty with temporomandibular joint opening. Ventilation difficulty and increased peak inspiratory pressure were noticed shortly after tracheal intubation, and bronchoscopy was performed for diagnosis. The bronchi were filled with a clear mucous secretion. Removal of the secretion improved respiration and decreased the peak inspiratory pressure. A chest roentgenogram taken prior to extubation showed right upper lobe atelectasis. A diagnosis of sinobronchial syndrome was made postoperatively. The etiology of the acutely developed atelectasis was unclear. However, the latent syndrome may have induced excessive airway secretion with stimuli such as endotracheal intubation.

Use of dynamic compliance for open lung positive end-expiratory pressure titration in an experimental study

OBJECTIVE

We tested whether the continuous monitoring of dynamic compliance could become a useful bedside tool for detecting the beginning of collapse of a fully recruited lung.

DESIGN

Prospective laboratory animal investigation.

SETTING

Clinical physiology research laboratory, University of Uppsala, Sweden.

SUBJECTS

Eight pigs submitted to repeated lung lavages.

INTERVENTIONS

Lung recruitment maneuver, the effect of which was confirmed by predefined oxygenation, lung mechanics, and computed tomography scan criteria, was followed by a positive end-expiratory pressure (PEEP) reduction trial in a volume control mode with a tidal volume of 6 mL/kg. Every 10 mins, PEEP was reduced in steps of 2 cm H2O starting from 24 cm H2O. During PEEP reduction, lung collapse was defined by the maximum dynamic compliance value after which a first measurable decrease occurred. Open lung PEEP according to dynamic compliance was then defined as the level of PEEP before the point of collapse. This value was compared with oxygenation (Pao2) and CT scans.

MEASUREMENTS AND MAIN RESULTS

Pao2 and dynamic compliance were monitored continuously, whereas computed tomography scans were obtained at the end of each pressure step. Collapse defined by dynamic compliance occurred at a PEEP of 14 cm H2O. This level coincided with the oxygenation-based collapse point when also shunt started to increase and occurred one step before the percentage of nonaerated tissue on the computed tomography exceeded 5%. Open lung PEEP was thus at 16 cm H2O, the level at which oxygenation and computed tomography scan confirmed a fully open, not yet collapsed lung condition.

CONCLUSIONS

In this experimental model, the continuous monitoring of dynamic compliance identified the beginning of collapse after lung recruitment. These findings were confirmed by oxygenation and computed tomography scans. This method might become a valuable bedside tool for identifying the level of PEEP that prevents end-expiratory collapse.

Frequency and Predictors of Return to Incentive Spirometry Volume Baseline After Cardiac Surgery

Incentive spirometry (IS) is routinely used in most clinical settings, but evaluation of patient efficacy of IS is not standardized. The purpose of this study was to describe the degree and predictors of return to preoperative IS volume after cardiac surgery. IS volumes were documented in 69 subjects (71% men; mean age, 59 years) undergoing cardiac surgery during the preoperative evaluation and twice daily postoperatively. Nineteen percent of subjects achieved their IS preoperative volume by hospital discharge. Based on highest volume achieved, subjects achieved an average of 75% of their preoperative volume by discharge, and only age and number of bypass grafts predicted return to preoperative IS volume. These data may assist nurses and patients to set realistic goals for postoperative IS volume achievement.

Medical qualification of a commercial spaceflight participant: not your average astronaut

BACKGROUND

Candidates for commercial spaceflight may be older than the typical astronaut and more likely to have medical problems that place them at risk during flight. Since the effects of microgravity on many medical conditions are unknown, physicians have little guidance when evaluating and certifying commercial spaceflight participants. This dynamic new era in space exploration may provide important data for evaluating medical conditions, creating appropriate medical standards, and optimizing treatment alternatives for long-duration spaceflight.

CASE

A 57-yr-old spaceflight participant for an ISS mission presented with medical conditions that included moderately severe bullous emphysema, previous spontaneous pneumothorax with talc pleurodesis, a lung parenchymal mass, and ventricular and atrial ectopy. The medical evaluation required for certification was extensive and included medical studies and monitoring conducted in analogue spaceflight environments including altitude chambers, high altitude mixed-gas simulation, zero-G aircraft, and high-G centrifuge. To prevent recurrence of pneumothorax, we performed video-assisted thoracoscopic pleurodesis, and to assess lung masses, several percutaneous or direct biopsies. The candidate's 10-d mission was without incident.

CONCLUSION

Non-career astronauts applying for commercial suborbital and orbital spaceflight will, at least in the near future, challenge aerospace physicians with unknowns regarding safety during training and flight, and highlight important ethical and risk-assessment problems. The information obtained from this new group of space travelers will provide important data for the evaluation and in-flight treatment of medical problems that space programs have not yet addressed systematically, and may improve the medical preparedness of exploration-class missions.

Beyond Ortner's syndrome--unusual pulmonary complications of the giant left atrium

INTRODUCTION

The giant left atrium (GLA) is a complication of severe mitral valve disease and causes morbidity by compressing adjacent intra-thoracic structures.

CLINICAL PICTURE

We report 2 cases of unusual pulmonary complications of the GLA. Case 1 developed recurrent collapse of the left lung due to left main bronchus compression. Case 2 was diagnosed with right middle lobe compression and collapse.

TREATMENT AND OUTCOME

Case 1 was successfully treated by mitral valve replacement and left atrial reduction surgery. Case 2 was treated conservatively.

CONCLUSION

Pulmonary atelectasis may occur in patients with GLA due to bronchopulmonary compression. Surgical management with valve replacement and atrial reduction may be necessary to relieve airway compression.

Positron emission tomography for target volume definition in the treatment of non-small cell lung cancer

The additional benefit of positron emission tomography (PET) in the initial staging of non-small cell lung cancer (NSCLC) has generated interest in 18F-fluorodeoxyglucose (FDG) PET as a means of defining the extent of primary lung tumour for radiotherapy treatment planning (RTP). A review of published data suggests that PET results in a reduction in the CT-derived GTV for NSCLC primary target volume in 15% of the patients. This is principally due to the ability of PET to distinguish tumour from atelectasis. However, the difficulty of tumour edge definition, limited spatial resolution and tumour motion during image acquisition currently limits the accuracy of PET in target volume delineation in NSCLC without adjacent lung consolidation. This is compounded by the lack of data correlating PET with spatial pathology at the primary tumour site. With the current technical limitations, it is not established that PET can add accuracy to the CT-defined primary target delineation in RTP of NSCLC. It is hoped that advances in PET and combined PET/CT imaging may overcome some of the technical limitations. Future use of PET for primary tumour delineation in NSCLC will also be critically dependent on the detailed studies of imaging-pathology correlation.

Respiratory compliance but not gas exchange correlates with changes in lung aeration after a recruitment maneuver: an experimental study in pigs with saline lavage lung injury

INTRODUCTION

Atelectasis is a common finding in acute lung injury, leading to increased shunt and hypoxemia. Current treatment strategies aim to recruit alveoli for gas exchange. Improvement in oxygenation is commonly used to detect recruitment, although the assumption that gas exchange parameters adequately represent the mechanical process of alveolar opening has not been proven so far. The aim of this study was to investigate whether commonly used measures of lung mechanics better detect lung tissue collapse and changes in lung aeration after a recruitment maneuver as compared to measures of gas exchange

METHODS

In eight anesthetized and mechanically ventilated pigs, acute lung injury was induced by saline lavage and a recruitment maneuver was performed by inflating the lungs three times with a pressure of 45 cmH2O for 40 s with a constant positive end-expiratory pressure of 10 cmH2O. The association of gas exchange and lung mechanics parameters with the amount and the changes in aerated and nonaerated lung volumes induced by this specific recruitment maneuver was investigated by multi slice CT scan analysis of the whole lung.

RESULTS

Nonaerated lung correlated with shunt fraction (r = 0.68) and respiratory system compliance (r = 0.59). The arterial partial oxygen pressure (PaO2) and the respiratory system compliance correlated with poorly aerated lung volume (r = 0.57 and 0.72, respectively). The recruitment maneuver caused a decrease in nonaerated lung volume, an increase in normally and poorly aerated lung, but no change in the distribution of a tidal breath to differently aerated lung volumes. The fractional changes in PaO2, arterial partial carbon dioxide pressure (PaCO2) and venous admixture after the recruitment maneuver did not correlate with the changes in lung volumes. Alveolar recruitment correlated only with changes in the plateau pressure (r = 0.89), respiratory system compliance (r = 0.82) and parameters obtained from the pressure-volume curve.

CONCLUSION

A recruitment maneuver by repeatedly hyperinflating the lungs led to an increase of poorly aerated and a decrease of nonaerated lung mainly. Changes in aerated and nonaerated lung volumes were adequately represented by respiratory compliance but not by changes in oxygenation or shunt.

Rounded atelectasis associated with pulmonary lymphangioleiomyomatosis

Rounded atelectasis is an unusual form of lung collapse that develops as a consequence of pleural diseases. Among a variety of conditions, asbestos inhalation has been attributed in most cases, but many other causes have also been implicated. Here, we describe the first case of rounded atelectasis and pneumothorax associated with pulmonary lymphagioleiomyomatosis.

Pulmonary atelectasis: a pathogenic perioperative entity

Atelectasis occurs in the dependent parts of the lungs of most patients who are anesthetized. Development of atelectasis is associated with decreased lung compliance, impairment of oxygenation, increased pulmonary vascular resistance, and development of lung injury. The adverse effects of atelectasis persist into the postoperative period and can impact patient recovery. This review article focuses on the causes, nature, and diagnosis of atelectasis. The authors discuss the effects and implications of atelectasis in the perioperative period and illustrate how preventive measures may impact outcome. In addition, they examine the impact of atelectasis and its prevention in acute lung injury.

Rounded atelectasis of the lung

Rounded atelectasis of the lung (RA) is a lesion well described in the medical literature, yet often very difficult to diagnose. In recent years, the widespread use of high-resolution imaging modalities employed in the struggle against cancer, coinciding with the peak of the asbestos epidemic, have boosted the detection frequency of RA. However, its differential diagnosis still poses a challenge to the pulmonary specialist and the radiologist, as little is known about its pathogenesis. Furthermore, the multifactorial etiology of RA and its occasional coexistence with lung cancer make the task of confidently ruling out malignancy sometimes daunting. This article attempts to provide an update on RA's etiology, radiological evaluation, clinical management, and prognosis based on recent advances in broadly available diagnostic modalities and minimally invasive interventional procedures. An exemplary case of post-tuberculous RA is illustrated, as RA often presents as an unusual finding of a fairly common disease.

[Pulmonary infection caused by non-tuberculous mycobacteria in two patients with bronchiectasis]

Two patients, a woman aged 67 years and a man aged 80 years, had chronic cough among other respiratory symptoms. In the woman, chest radiograph and CT-scan revealed partial atelectasis of the middle lobe and bronchiectasis. In the man, an interstitial pattern was seen on chest radiograph, and CT scan showed diffuse bronchiectasis. In both the man and the woman, non-tuberculous mycobacteria were identified (Mycobacterium avium complex and Mycobacterium abscessus, respectively). Treatment was successful in both patients. Non-tuberculous mycobacteria can cause considerable pulmonary infection in patients with bronchiectasis.

[Lung rounded atelectasis. A benign lesion due to asbestos]

BACKGROUND AND OBJECTIVE

Rounded atelectasis (RA) is an unusual form of pulmonary lesion often confounded with pulmonary neoplasia. We studied the main diagnostic and evolutive characteristics of a series of patients diagnosed with RA.

PATIENTS AND METHOD

Twenty patients diagnosed of RA in a tertiary hospital in Catalonia were included in the study. The diagnostic criterion of RA was strictly based on thoracic CT. Clinical data and pulmonary function tests were also evaluated. Four teen patients underwent a long term follow-up.

RESULTS

Asbestos was the cause of RA in 13 cases (65%); 7 had previously had homolateral pleural effusion; 5 pulmonary tuberculosis and in 1 case RA appeared at the lung biopsy site. The most frequent localization was inferior lobes and left side (70%). Eighteen patients had a ventilatory disorder: 10 restrictive, 6 mixed and 2 obstructive. In no case, RA evolved to malignancy.

CONCLUSIONS

RA is a benign lesion mainly due to asbestos showing well-defined morphological characteristics.

Computed tomography--a possible aid in the diagnosis of smoke inhalation injury?

Inhalation injury is an important contributor to morbidity and mortality in burn victims and can trigger acute lung injury and acute respiratory distress syndrome (ARDS) (1-3). Early diagnosis and treatment of inhalation injury are important, but a major problem in planning treatment and evaluating the prognosis has been the lack of consensus about diagnostic criteria (4). Chest radiographs on admission are often non-specific (5, 6), but indicators include indoor fires, facial burns, bronchoscopic findings of soot in the airways, and detection of carbon monoxide or cyanide in the blood (7). Changes in the lungs may be detected by bronchoscopy with biopsy, xenon imaging, or measurement of pulmonary extracellular fluid (4, 5, 8). These methods have, however, been associated with low sensitivity and specificity, as exemplified by the 50% predictive value in the study of Masanes et al. (8). Computed tomographs (CTs) are better than normal chest radiographs in the detection of other pulmonary lesions such as pulmonary contusion (9, 10). The importance of CT scans in patients with ARDS has been reviewed recently (9), but unfortunately there has been no experience of CT in patients with smoke inhalation injury. To our knowledge, there are only two animal studies reporting that smoke inhalation injury can be detected by CT (4, 11); specific changes in human CT scans have not yet been described. Therefore, confronted with a patient with severe respiratory failure after a burn who from the history and physical examination showed the classic risk factors for inhalation injury, we decided to request a CT.