Lung lobe torsion in dogs: 52 cases (2005–2017)

Abstract

Objective To report outcomes and risk factors for mortality in dogs that underwent surgical management of lung lobe torsion. Study design Retrospective case series from 5 veterinary teaching hospitals (2005–2017). Animals Fifty dogs with 52 instances of lung lobe torsion. Methods Data collected from medical records included signalment, clinical findings, results of clinicopathologic testing and diagnostic imaging, surgical treatment, lung lobe affected, intraoperative and postoperative complications, histopathologic and microbiologic findings, and outcome. Follow‐up was obtained from medical records and telephone contact with primary care veterinarians. Results Fifty‐two instances of lung lobe torsion were identified in 50 dogs, with a median follow‐up of 453 days (range, 0–3075). Forty‐six (92%) dogs survived to discharge. Dogs with concurrent torsion of the right cranial and middle lung lobes were less likely to survive (2/4) than those with torsion of the left cranial lung lobe (22/22). No other risk factors for mortality prior to hospital discharge were identified. Overall median survival time after hospital discharge was 1369 days. Four dogs had >1 episode of lung lobe torsion. Conclusion The percentage of dogs surviving to discharge after surgical treatment of lung lobe torsion was higher than previously reported. The short‐ and long‐term prognosis was excellent with surgical treatment of lung lobe torsion. Clinical significance Surgery should be recommended when lung lobe torsion is suspected because of the high survival to discharge rate and excellent long‐term prognosis.

Long‐term survival after treatment of idiopathic lung lobe torsion in 80 cases

“…Mortality associated with LLT in human patients ranges from 8.3% to 16% . Reported mortality rate in dogs ranges from 31% to 61%; however, more recent reports described a lower rate ranging from 8% to 14% …”

“…Lung lobe torsion (LLT) is a potentially life‐threatening condition in dogs and cats, consisting of a lobar rotation of the bronchovascular pedicle at the hilus. This condition results in airway obstruction and vascular compromise . The incidence of LLT remains unclear in small animals but in man ranges between 0.09% and 0.4%.…”

“…Overall, most cases of LLT occur after a lung lobectomy, with the right middle lung lobe being the most affected after right upper lobectomy . In dogs, the etiology is primary (spontaneous or idiopathic) or secondary to an underlying process such as pulmonary (eg, neoplasia) or pleural disease (eg, pleural effusion) . Unlike the terminology used in human medicine, primary , idiopathic , and spontaneous are terms used interchangeably to describe LLT in animals when no predisposing factors can be identified …”

“…Large deep‐chested dogs, such as Afghan hounds as well as other smaller breeds (eg, pugs), are overrepresented. However, LLT has been also documented in a diversity of breeds ranging from Chihuahuas to Newfoundlands . It has been reported that small breed dogs are typically affected by secondary LLT, whereas primary LLT is more common in pugs; large breed dogs are equally affected by primary and secondary LLT …”

Utility of bronchoscopy combined with surgery in the treatment and outcomes of dogs with intrathoracic disease secondary to plant awn migration

“…Long‐term complications occurring in this cohort included lung lobe torsion of the right middle lung lobe as well as fungal aspergillosis of the right middle lung lobe. Lung lobe torsion in dogs is infrequently reported, and risk factors are poorly understood . It is possible that surgical manipulation, relating to the lung lobectomy or thoracic exploration, may have played a role in development of lung lobe torsion, although it is unknown when the torsion event occurred in the individual animal.…”