Pneumothorax In Dogs Research Articles

Improved detection of air-filled lesions using computed tomography in dogs with recurrent spontaneous pneumothorax through reduction of pulmonary atelectasis via positive pressure ventilation.

Spontaneous pneumothorax in dogs is predominantly caused by the rupture of air-filled lesions, such as bullae or blebs. The efficacy of Computed Tomography (CT) in detecting these lesions has been deemed limited due to its reportedly low sensitivity. This retrospective, cross-sectional study investigates the utility of CT in eight dogs diagnosed with recurrent pneumothorax, all of which had surgical confirmation of the cause of the pneumothorax. Thoracic radiographs were obtained before and the day following the CT studies. Initially, a CT study was conducted without positive pressure ventilation (pre-PPV CT). Subsequent CT studies were performed post-evacuation of pneumothorax and with positive pressure ventilation of 15 cmH2O until lung atelectasis was resolved (post-PPV CT). The pre-PPV CT and post-PPV CT images were anonymized and reviewed by two board-certified radiologists. The presence and morphology of air-filled lesions were evaluated on all images. Surgical findings were recorded and compared to the CT findings. Air-filled lesions were detected in 5 out of 8 dogs in the pre-PPV CT studies and in all 8 dogs in the post-PPV CT studies. The CT findings of air-filled lesions were consistent with surgical findings. None of the dogs showed increased severity of pneumothorax in radiographs taken the day following the CT studies. The study concludes that the resolution of lung atelectasis by evacuation of pneumothorax and positive pressure ventilation during CT studies is feasible and enhances the detection of air-filled lesions in dogs with recurrent spontaneous pneumothorax. This could potentially aid in improving surgical planning.

Thoracic CT incidental pulmonary bullae in dogs: Characterization, interobserver variability, and general anesthesia risks.

Ruptures of pulmonary blebs and bullae are the most common cause of spontaneous pneumothorax in dogs. Incidental bullae/blebs have been documented in otherwise healthy people, however information for veterinary patients is currently lacking. Objectives of this retrospective, observer agreement, analytical study were to characterize incidental bullae in thoracic CT studies of dogs, assess interobserver variability for characterizing the bullae, and assess anesthesia risks. Inclusion criteria were dogs presenting for non-pneumothorax related reasons that had a thoracic CT at a single specialty and emergency hospital from 2012 to 2021 and had a bulla listed in the CT report. Medical records for dogs meeting inclusion criteria were reviewed to collect data on signalment, weight, total number of general anesthesia procedures 2 years prior and 2 years following the CT scan, and adverse anesthesia events. In addition, the CT images were reviewed by three American College of Veterinary Radiology-certified veterinary radiologists to collect data on the location, size, number of bullae and thickness of the bulla wall. A total of 1119 dogs met initial inclusion criteria and 74 dogs were included in analyses. There was no sex predilection for incidental pulmonary bullae. Bullae were more commonly found in older (median age 11.3 years), large breed dogs (median weight 20.7kg). A solitary bulla of less than 1cm was the most common finding with no apparent predilection for a particular lung lobe. There was strong correlation among the three radiologists for bulla location, size, and number, but weak correlations for bulla wall thickness. No adverse anesthesia events were found following CT anesthesia or following repetitive anesthesia procedures.

Porcupine quilling-associated pneumothorax in dogs: 25 cases (2001-2022).

To describe the clinical outcome of dogs that developed pneumothorax after an encounter with a porcupine. 25 client-owned dogs from 2 practices in New England. The medical records were searched for those of dogs that underwent care for porcupine quilling-associated pneumothorax (PQAP) between August 1, 2001, and October 15, 2023. Dogs were all large-breed dogs or large mixed-breed dogs and most frequently had clinical signs associated with pneumothorax, including labored breathing and tachypnea. No cases occurred in winter months. Diagnostic imaging was useful for identifying pneumothorax, but not for localizing quills. Twenty-one of the 25 dogs underwent median sternotomy for quill removal, with quills found in lung tissue of 19 dogs. Two dogs had no intrathoracic quills identified at thoracotomy, but residual quills were identified in the intercostal muscles. Four dogs were discharged without surgery after apparent resolution of the pneumothorax. All dogs survived to hospital discharge; however, 5 dogs required subsequent quill removal from ongoing quill migration. Porcupine quillings may result in traumatic pneumothorax associated with quill migration. Following quill removal, monitoring for the development of a pneumothorax is advised. Surgical removal of quills from the lungs has a good prognosis.

A Rare Cause of Severe Biventricular Dyssynchrony During Venoarterial Extracorporeal Membrane Oxygenation for COVID-19 Respiratory Failure

A Rare Cause of Severe Biventricular Dyssynchrony During Venoarterial Extracorporeal Membrane Oxygenation for COVID-19 Respiratory Failure

Pneumothorax secondary to a Pulmonary Bullae in a dog

Background: Pulmonary bullae are thin-walled cavitary lesions within the subpleural parenchyma. They are a result of the destruction, dilatation and coalescence of bordering alveoli and their rupture is the most common cause of pneumothorax in dogs. Radiographic and CT imaging are excellent tools for identifying and quantifying pneumothorax. Surgical treatment is considered standard for treatment of pneumothorax consequential to pulmonary bullae. The aim of this report was to describe a case of pneumothorax secondary to pulmonary bullae in a dog.Case: A 5-year-old male crossbreed dog, weighing 11.5 kg, was presented to the Uberaba’s Veterinary Hospital due to becoming easily tired in the previous 3 weeks, and its worsening in the last 2 days by presenting panting. The dog’s guardian did not witness any traumas, but informed that the animal resided with other 14 dogs and also that it frequently collided the thorax against the door when it came down from the bed. Physical examination showed diaphragmatic breathing, inspiratory dyspnea and stridor lung sound. Thoracocentesis revealed presence of air in the pleural cavity and pneumothorax. Radiographic images confirmed this condition. The dog stayed in the hospital and chest drains were placed. Since the amount of sucked air did not reduce with time and due to the emergence of subcutaneous emphysema, the dog went through exploratory thoracotomy that revealed impairment of the right caudal lung lobe, proceeding to lobectomy. The dog stayed in the hospital with chest drains until the contents of the suctions reduced significantly. With the removal of the drains, the dog was sent home and had a full recovery. Histopathology of the impaired lung revealed pulmonary bullae.Discussion: The dog from this report presented clinical signs consistent with pneumothorax, such as dyspnea, diaphragmatic breathing and exercise intolerance. Radiography of the chest region revealed images consistent with this condition, as it is an excellent tool for identifying it. This dog’s guardian was unable to confirm if there was occurrence of trauma due to the large number of cohabitants. In dogs, spontaneous pneumothorax commonly results from the rupture of pulmonary bullae, and these bullae may result from trauma, infectious diseases, thrombosis, obstructive, neoplastic, congenital or idiopathic conditions. Except from trauma, there were no evidence to support any of the other causes of pulmonary bullae in this case. Traumatic injuries are very common in veterinary medicine, and blunt thoracic traumas with consequential pneumothorax are especially common. The emerging of subcutaneous emphysema, as happened with this dog, is frequently associated with pneumomediastine, and rarely has pathophysiologic impairments. The patient stayed in the hospital for support therapy and thoracocentesis, corroborating with literature; but since there was no improvement, it went through exploratory lobectomy, which revealed impairment of the right caudal lung lobe, proceeding to its exeresis. Surgical intervention is standard procedure in these cases. Histopathology of the impaired lung suggested the presence of pulmonary bullae. In literature, histopathological definitions for this condition are inconsistent, but usually locate the bullae within the pulmonary parenchyma, having walls less than 1 mm thick. Through radiology, unlike with cysts, identifying pulmonary bullae is challenging. In conclusion, this report showed that pulmonary bullae should be considered as a differential diagnose in patients showing pneumothorax considering it is hard to identify through imaging, and that it is important to adopt early therapy and surgical intervention for better outcomes.Keywords: dyspnea, panting, pulmonary lobectomy, thoracotomy, chest drain.Titulo: Pneumotórax secundário a bolha pulmonar em cão.Descritores: dispneia, ofegante, lobectomia pulmonar, toracotomia, dreno torácico.

Recurrent Spontaneous Pneumothorax in a Maltese Dog with Endogenous Lipoid Pneumonia

Background: Pneumothorax is a clinical condition which can cause respiratory distress. It can have as its origin traumatic causes or even classified as spontaneous, mainly related to diseases of the lung parenchyma. Lipoid pneumonia is rarely described in dogs, and it is characterized by globules of lipid in the alveolar spaces. Endogenous lipoid pneumonia (EnLP) occurs when lesions on pulmonary cells release cholesterol and other lipids in the alveoli. There is no clinical approach established for EnLP in veterinary patients. The aim of this report is to describe a case of a young Maltese dog, with recurrent spontaneous pneumothorax in which EnLP was diagnosed Post mortem.Case: A 2-year-old sexually intact male Maltese dog was evaluated for restrictive dyspnea. Clinicopathologic findings included cyanotic, muffled chest auscultation with hypersonic thoracic percussion. Chest x-ray demonstrated an increase in pleuropulmonary radio transparency and a floating-looking heart, indicating pneumothorax. Complete blood counts andbiochemical panel results were normal. Dirofilaria immitis antigen test results were negative. Computed tomography demonstrated slightly hyper-expanded pulmonary fields, with slightly enlarged reticular marking with areas of mild multicentric panlobular emphysema and a fracture on the sixth left rib. The treatment was focused on improving the breathing pattern through sedation, supplementation with oxygen, and thoracentesis. Owing to the reserved prognosis of the case, the unknown etiology of the recurrent pneumothorax, and the clinical worsening of the patient, the owner opted for euthanasia. Necropsy displayed multiple, circular whitish areas in the lungs, distributed over the surface of all lobes. Histopathological examination revealed pulmonary tissue with the subpleural micronodular foci, multifocal to coalescent, with a moderate accumulation of foamy intra-alveolar macrophages, occasionally multinucleate, associated with cholesterol crystals compatible with endogenous lipid pneumonia. Discussion: The patient presented with clinical signs and physical examination characteristics of pneumothorax at the first visit. After the pneumothorax diagnosis, and clinical stabilization of the patient. No predisposing factor for the formation of the pneumothorax was identified as the radiography revealed only bronchitis and blood tests were normal, the patient was thus discharged after 24 h, with the recommendations for observing the breathing pattern. Initially, spontaneous pneumothorax was suspected. The antibiotics were administered since bacterial pneumonia, although not confirmed on chest x-ray, is the main cause of pneumothorax in dogs is lung parenchyma disease. With the worsening of the clinical condition of the patient, CT was performed and did not demonstrate any findings that would justify the presence of pneumothorax. Despite the placement of the chest tube for facilitating the management of thoracentesis, there was no stabilization of the condition, enhancing the frequency of centesis procedures, which led to the decision to euthanize. The microscopic examination of the pulmonary alterations was decisive for the diagnostic conclusion. The visualization of the accumulation of foamy intra-alveolar macrophages, occasionally multinucleate, associated with cholesterol crystals, was responsible for the diagnosis of EnLP. This condition is rarely described in dogs and as in the present report, it is a noninfectious inflammatory condition, characterized by intra- or extracellular globules of lipid in the alveolar spaces. In the present report, although it was not possible to determine the etiology of EnLP, we can conclude that although rare, it can affect dogs and can generate severe clinical repercussions.

Fatal pneumothorax in a dog caused by a lesion resembling congenital pulmonary airway malformation (CPAM) of children

An 8 month old boxer dog was referred for management of acute spontaneous pneumothorax. CT showed multiple variably sized bullae in the right middle lung lobe, and partial or complete...

Iatrogenic Pneumothorax Associated with Inadvertent Intrapleural NGT Misplacement in Two Dogs

This case report presents two cases of inadvertent intrapleural nasogastric tube (NGT) misplacement with consequent creation of a bronchopleural fistula and the development of an iatrogenic pneumothorax in dogs. Due to the simplicity and relative ease of NGT placement and the lack of reported life-threatening complications in the veterinary literature, the serious risks associated with this procedure are often overlooked. Although pulmonary complications with NGT misplacement have been previously reported in the human literature, serious and potentially fatal complications have not been currently described in veterinary patients. Both of the cases described herein were medically managed with successful outcomes; however, one case was associated with significant morbidity.

Sensitivity, positive predictive value, and interobserver variability of computed tomography in the diagnosis of bullae associated with spontaneous pneumothorax in dogs: 19 cases (2003–2012)

To determine the sensitivity, positive predictive value, and interobserver variability of CT in the detection of bullae associated with spontaneous pneumothorax in dogs. Retrospective case series. 19 dogs with spontaneous pneumothorax caused by rupture of bullae. Dogs that had CT for spontaneous pneumothorax caused by rupture of bullae confirmed at surgery (median sternotomy) or necropsy were included. Patient signalment, CT protocols, and bulla location, size, and number were obtained from the medical records. Computed tomographic images were reviewed by 3 board-certified radiologists who reported on the location, size, and number of bullae as well as the subjective severity of pneumothorax. Sensitivities of the 3 readers for bulla detection were 42.3%, 57.7%, and 57.7%, with positive predictive values of 52.4%, 14.2%, and 8.4%, respectively, with the latter 2 readers having a high rate of false-positive diagnoses. There was good interobserver agreement (κ = 0.640) for correct identification of bullae. Increasing size of the bulla was significantly associated with a correct CT diagnosis in 1 reader but not in the other 2 readers. Correct diagnosis was not associated with slice thickness, ventilation protocol, or degree of pneumothorax. Sensitivity and positive predictive value of CT for bulla detection were low. Results suggested that CT is potentially an ineffective preoperative diagnostic technique in dogs with spontaneous pneumothorax caused by bulla rupture because lesions can be missed or incorrectly diagnosed. Bulla size may affect visibility on CT.

Spontaneous pneumothorax secondary to reactive bronchopneumopathy in a dog

An 8-year-old 38-kg (84-lb) castrated male German Shepherd Dog cross was evaluated because of respiratory distress secondary to pneumothorax (detected radio-graphically prior to referral). CT of the thorax confirmed the presence of pneumothorax and revealed pulmonary blebs without evidence of infiltrative pulmonary changes. A tentative diagnosis of primary spontaneous pneumothorax was made. Exploratory median sternotomy revealed emphysematous changes along the margins of all lung lobes, with the ventral margins of the left cranial, right cranial, and right middle lung lobes most affected. Partial lobectomies of the ventral aspects of these lobes were performed. Histologic examination of tissue samples from the lung lobes revealed diffuse smooth muscle hypertrophy of the terminal and respiratory bronchioles with moderate numbers of peribronchiolar eosinophils. Mucus plugs and mucous cell metaplasia within the airway epithelium were also evident. After surgery, clinical signs resolved and the dog was discharged from the hospital 2 days later. Eight months after surgery, the dog developed a mild cough, and treatment with prednisolone (tapering dosage starting at 0.5 mg/kg [0.023 mg/lb], PO, q 12 h) was initiated. Dosage reduction resulted in recurrence of coughing; however, with continued prednisolone treatment at a dosage of 0.5 mg/kg, PO, once daily, the dog was not coughing at 10 months after surgery. Reactive bronchopneumopathy should be included as a differential diagnosis for spontaneous pneumothorax in dogs.

Spontaneous pneumothorax secondary to granulomatous pneumonia caused by Angiostrongylus vasorum in a dog in Denmark

Angiostrongylosis was diagnosed in a 2-year-old whippet which was presented with spontaneous pneumothorax based on detection of Angiostrongylus vasorum first-stage larvae on lung histology and in faeces. Thoracic radiographs and computed tomography imaging revealed bilateral pneumothorax with a gas-filled bulla in the right caudal lung lobe. On thoracotomy, continuous air leakage was observed from the bulla. Histologic examination of lobectomised tissue confirmed the diagnosis of chronic granulomatous pneumonia due to A. vasorum infection. The dog was treated with fenbendazole until negative for larvae on faecal examination and recovered completely. The most commonly reported clinical signs of angiostrongylosis are related to the respiratory tract, including cough and dyspnoea leading to exercise intolerance, and rarely haemothorax (Chapman et al. 2004, Sasanelli et al. 2008, Koch and Willesen 2009). Pneumothorax has been mentioned in association with angiostrongylosis (Martin et al. 1993, Gallagher et al. 2012), but has not been described in detail so far. Identification of the underlying cause is important for the prognosis and treatment of pneumothorax. Angiostrongylosis should be considered as a possible aetiological cause of spontaneous pneumothorax in dogs even in the absence of radiological changes supportive of an A. vasorum infection. E. H. Spodsberg, J. E. Miles, F. J. McEvoy and J. L. Willesen University Hospital for Companion Animals, Department of Veterinary Clinical and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark

Use of pleural access ports for treatment of recurrent pneumothorax in two dogs

An 8-year-old castrated male mixed-breed dog (dog 1) and a 13-year-old spayed female mixed-breed dog (dog 2) were evaluated because of spontaneous pneumothorax. Both dogs had decreased bronchovesicular sounds with coughing, tachypnea, cyanosis, lethargy, or a combination of these clinical signs. Radiographic examination revealed pneumothorax in both dogs and consolidation of a lung lobe in dog 2. Pneumothorax was alleviated following thoracocentesis in both dogs but recurred. Dog 1 was initially treated by placement of a thoracostomy tube but underwent thoracotomy when pneumothorax recurred after tube removal; left caudal lung lobectomy was performed because a ruptured bulla was suspected, and a pulmonary bulla was histologically confirmed. Dog 2 underwent thoracotomy with left caudal lung lobectomy and partial removal of the left cranial lung lobe; diffuse pulmonary emphysema was diagnosed. This dog underwent a second surgery for right caudal lung lobectomy because of torsion. When pneumothorax recurred and additional surgery was not considered feasible, pleural access ports were placed in both dogs for repeated removal of air from the thoracic cavity. Ports were used clinically for 17 days in dog 1 and 14 days in dog 2. Dog 1 successfully underwent another surgery when pneumothorax recurred 18 days after port placement but was euthanized 17 months later when dyspnea and tachypnea recurred. Pneumothorax had not recurred further in dog 2 twenty-three months after port placement. Findings suggested that pleural access ports may have a role in the management of spontaneous pneumothorax in dogs.

Comparison of the amounts of air leakage into the thoracic cavity associated with four thoracostomy tube placement techniques in canine cadavers

To compare the amount of air leakage into the thoracic cavity associated with each of 4 thoracostomy tube placement techniques in canine cadavers. 28 canine cadavers. Thoracostomy tube placement techniques (7 cadavers/technique) included subcutaneous tunneling with a silicone tube by use of Carmalt forceps or with a polyvinyl chloride tube by use of a trocar (SC-CARM and SC-TRO, respectively) and tunneling under the latissimus dorsi muscle with similar tube-instrument techniques (LD-CARM and LD-TRO, respectively). Differences in intrapleural pressures (IPPs) measured before and after tube placement and before and after tube removal were calculated; duration of air leakage around the tubes was assessed by use of a 3-chamber thoracic drainage system. Tunneling method and depth had no interaction effect on the difference in IPP measured before and after tube placement; the IPP difference for both forceps technique groups was significantly greater than findings for both trocar technique groups. Tunneling method and depth had an interaction effect on the difference in IPP measured before and after tube removal; compared with SC-TRO and LD-CARM group differences, the SC-CARM group difference was significantly greater, but the LD-TRO group difference was similar. More intermittent air leakage was associated with the 2 forceps techniques than with the 2 trocar techniques. Trocar-implemented thoracostomy tube placement in canine cadavers resulted in less air leakage than the forceps method. Air leakage upon tube removal was less pronounced for the LD-CARM technique than the SC-CARM technique. The LD-TRO technique is recommended to prevent iatrogenic pneumothorax in dogs.

Produção de pneumotórax em cães e manejo por toracoscopia paraxifóide transdiafragmática

O presente estudo foi desenvolvido com o objetivo de avaliar a técnica de toracoscopia paraxifóide transdiafragmática no diagnóstico e no tratamento do pneumotórax produzido experimentalmente em cães. Para tanto, foram utilizados 11 cães que foram submetidos à produção de pneumotórax grave a partir da aplicação de 10mLkg-1 de ar em cada hemitórax até apresentarem descompensação hemodinâmica. Concomitantemente, foram aferidas a correlação entre a pressão venosa central (PVC) e o volume de ar introduzido (mL kg-1), bem como FC, FR, TPC, SpO2 e coloração das mucosas. O pneumotórax foi tratado pela aplicação de dreno torácico por meio de um trocarte inserido no lado direito (seis animais) ou esquerdo (cinco animais) do apêndice xifóide por meio do diafragma. A introdução em volume igual ou superior a 50ml kg-1hemitórax-1 de ar causou descompensação cardiorrespiratória e elevação da PVC acima de 10cm H2O em todos os pacientes. A técnica proposta permitiu apropriado exame da cavidade torácica e aplicação do dreno com efetiva drenagem, sem a ocorrência de complicações trans e pós-operatórias, condição confirmada pela toracoscopia intercostal aos 15 dias de pós-operatório. Conclui-se que o modelo de produção do pneumotórax e a técnica de colocação de dreno proposta para o manejo dessa doença são adequados para cães.

Use of computed tomography for evaluation of lung lesions associated with spontaneous pneumothorax in dogs: 12 cases (1999–2002)

To evaluate use of computed tomography (CT) of the lungs, compared with conventional radiography, for detection of blebs and bullae associated with spontaneous pneumothorax in dogs. Retrospective case series. 12 dogs with spontaneous pneumothorax. Medical records were reviewed, and information was collected that included signalment, body weight, initial owner complaint, laboratory findings, radiographic findings, CT findings, medical and surgical treatment, histologic findings, complications, duration of hospitalization, and final outcome. Radiographs were excellent for identifying pneumothorax (sensitivity, 100%) but poor for identifying the underlying cause (bullae or blebs); these were identified in radiographs of only 2 of 12 dogs. Computed tomography allowed identification of bullae or blebs in 9 of 12 dogs. Ten of the 12 dogs were treated via surgery, and 17 affected lung lobes were identified. Four of the 17 affected lobes were identified via radiography. Thirteen of the 17 affected lobes were identified via CT; however, 1 lobe was incorrectly identified as the right caudal lobe instead of the right cranial lobe. Results suggested that CT is better than radiography for identifying the underlying causes of spontaneous pneumothorax.

Evaluation of praziquantel for treatment of experimentally induced paragonimiasis in dogs and cats

SUMMARY Praziquantel was used successfully for treatment of a small number of dogs and 1 cat infected with Paragonimus kellicotti. To further evaluate the usefulness of this drug in treating such infections, 7 cats and 7 dogs were inoculated orally with metacercariae (12 and 20 to 22, respectively) obtained from crayfish, then were treated after the infections became patent; 2 cats and 2 dogs served as noninfected controls. Beginning 1 week before infection, and continuing weekly thereafter, physical, hematologic, and fecal examinations were performed on each animal; thoracic radiography was performed every other week. By postinoculation week 6, all dogs given metacercariae had patent infection diagnosed on the basis of positive results of fecal examination. By postinoculation week 7, 5 cats had confirmed patent infection, but 2 cats given metacercariae never had patent infection or had signs of infection. Clinical signs of infection were minor and included increased respiratory tract noise, slight inducible cough, or mild dyspnea. Transient eosinophilia was detected in dogs around postinoculation week 3. Pretreatment radiography revealed cavitated lesions in cats only; pleural lines and patchy infiltrates in cats and dogs; or pneumothorax in dogs only. The treatment regimen consisted of 23 mg of praziquantel/kg of body weight given every 8 hours for 3 days; 1 infected cat and dog were not treated. By 11 days after treatment, eggs had disappeared from the feces of infected animals, and marked resolution of lung lesions was evident radiographically. The 2 untreated animals and 1 treated dog were euthanatized and necropsied to verify lesions and their resolution. All treated animals were considered cured of infection by use of this treatment regimen.

A thoracostomy tube for field and emergency department use

A small, easily insertable tube in combination with a one-way flutter valve serves as a quick but effective small chest tube for use in trauma both in the prehospital stage and the emergency department. The dart was effective in resolving pneumothorax in dogs and humans. Paramedics can be trained easily to use it.

BILATERAL AND UNILATERAL NONTUBERCULOUS SPONTANEOUS PNEUMOTHORAX

Whereas unilateral spontaneous pneumothorax is not infrequently encountered, a bilateral one is rarely encountered. However, one other case besides the one reported in this paper has been observed.* The case reported here was mentioned at a previous meeting of this society in a discussion of a paper by Graham, in 1923, relative to the experimental production of bilateral pneumothorax in dogs. It is remarkable that in these two human cases of bilateral pneumothorax, prompt recovery has resulted in spite of the collapse of both lungs (Fig. 1, A and B). In spontaneous pneumothorax, either unilateral or bilateral, it is not safe to infer that complete expansion of one or both lungs will result. In two cases observed by me the lung failed to expand in each case. One case was observed for about a period of a year and the other case for a period of more than six years