Pulmonary response to airway instillation of autologous blood in horses

Abstract

Pulmonary fibrosis and lung remodelling, characteristic of EIPH, are important because these lesions may enhance the severity of bleeding during exercise. A single instillation of autologous blood in the airspaces of the lung is not associated with pulmonary fibrosis. Therefore the pulmonary fibrosis described in EIPH must have other causes, such as repetitive bleeds, or the presence of blood in the pulmonary interstitium in addition to the airspaces. Prevention of pulmonary fibrosis through therapeutic intervention requires a better understanding of these mechanisms.

Specificity and sensitivity of ultrasonography and endoscopy for the diagnosis of exercise-induced pulmonary haemorrhage (EIPH) in 157 race horses

“…On the other hand, the low specificity of US makes it impossible to differentiate between CTA due to either the presence of blood or that of inflammatory fluid within the lung. Similar results were obtained for ER: where, on one hand, the absence of mucopus within the tracheal lumen allows one to rule out EIPH in 89% of the cases, and on the other hand the frequent finding of tracheal mucopus in EIPH-affected horses supports the hypothesis of a correlation between EIPH and lower airway inflammation (IAD) (Aguilera-Tejero et al 1995;Derksen et al 2007). Finally, ES confirmed its high sensitivity and specificity although it suffers from the limit that it must be performed within 90 minutes after strenuous exercise.…”

Diagnostic Approaches for the Assessment of Equine Chronic Pulmonary Disorders

“…Hemosiderophages were found in some horses with all other types of disorders secondary to inflammation or obstruction of the airways. Frequent concurrent finding of hemosiderophages in BALF and tracheal mucopurulent secretion had earlier been demonstrated and supports the hypothesis of correlation between EIPH and lower airway inflammation [56,57].…”

Repeated blood instillation into the airway of the horse does not cause pulmonary fibrosis

“…2002; Scotton et al . 2009), we and others have investigated the ability of the lung to clear autologous blood from the airspaces and the relationship of the blood to collagen deposition within the lung (McKane and Slocombe 2002; Derksen et al . 2007).…”

“…Most recently, we demonstrated that a single administration of autologous blood within the airways is rapidly cleared and does not induce pulmonary collagen accumulation (Derksen et al . 2007).…”

“…Selection of instillation sites: The methods used to identify sites of instillation, and instillation of the autologous blood or saline have been previously described (Derksen et al . 2007).…”