Respiratory Medicine

Latest News


Traumatic thoracic injuries are prevalent in small animals, particularly in dogs. The most common causes of thoracic trauma are motor vehicular accidents and bite wounds. Other possible, although less common mechanisms include gunshot, knife wounds or being kicked by a larger animal (horse/cow). Injuries may range from mild to life threatening.

i1-746729-1384172494363.jpg

Definitive diagnosis of pulmonary disease remains elusive at times. Cytological or histopathological samples are useful to help better classify the underlying cause as well as determine both prognosis and treatment course. Thus, it is prudent for the criticalist to have a strong grasp of the various techniques and options available for sampling.

i1-746672-1384172741076.jpg

Pulmonary vascular disease or pulmonary vascular obstructive disease (PVOD). is a catch-all term for conditions that affect the pulmonary circulation. These conditions are of particular importance to as they may result in severe respiratory dysfunction. As a review, the pulmonary and systemic circulation are in series, with the cardiac output of the left and right heart (in the absence of cardiac shunt) being equal.

The pleural space is defined as the area between the lungs and the chest wall. Normally there is no soft tissue or free air present in this space. A very small amount of fluid (undetectable on radiographs or ultrasound) may be present within the thoracic cavity. Clinical signs of pleural space disease include tachypnea or difficulty breathing.

i1_t-746678-1384172719630.gif

Pulmonary edema is defined as the accumulation of abnormal amount of extravascular lung water. Pulmonary edema may range from clinically insignificant to life-threatening. Pulmonary edema forms when there is an alternation in the balance of Starling forces (hydrostatic and colloid osmotic) between the interstitium and pulmonary capillary beds that favors increasing filtration to the interstitium. Increased capillary hydrostatic forces will result in a low protein edema fluid while lowered colloid osmotic forces will promote a high protein edema fluid.

Cough is a common presenting complaint for dogs and, to a lesser extent, cats. Cough is a sign of an underlying disorder, not a primary disease. Therefore, the cause of the cough should be identified and the underlying disease, not just the cough, should be treated.

Mycoplasma species have been isolated in our laboratory from cats with URTD (Veir et al 2004) and have been detected at a higher rate in cats with URTD than normal cats by other authors (Bannasch and Foley 2005). However, they are readily detected in the oropharynx and nasal cavity of normal cats as well (Randolph et al 1993, Tan et al 1977).

DogbronchitislayersCELLSpsd-673426-1384277670111.jpg

Eosinophilic bronchopneumopathy is thought to be a pulmonary hypersensitivity disorder that may be triggered by certain drugs, inhaled environmental allergens, or a parasitic, fungal, or bacterial respiratory tract infection.

Inhalant delivery of Aerosolized medication offers a number of theoretical benefits including an enormous absorptive surface area across a permeable membrane, a low enzyme environment that results in little drug degradation, avoidance of hepatic first-pass metabolism, and reproducible absorption kinetics.

i1-729613-1384189916454.jpg

Delivery of adequate oxygen to tissues and cells is the overall goal of the cardiovascular system. Oxygenation is dependant on cardiac output (heart rate and stroke volume), arterial blood pressure, circulating blood volume, and pulmonary function. Critically ill patients often have impairments to one or several of these processes resulting in hypoxemia, ischemia and cell death. Restoring these functions to normal insures oxygenation.

Table_t-727320-1384189872700.jpg

Cough is a common reason for dogs to be presented for veterinary care, and tracheal collapse is a common cause of chronic cough in dogs. The tracheal lumen remains open during both inspiration and expiration thanks to the support of cartilaginous rings.

Bacterial pneumonia encompasses a wide spectrum of disease from chronic to acute, unilobar or multilobar, and with clinical signs ranging from mild tachypnea or cough to rapidly progressive and fatal pulmonary infection. Cats are subject to bacterial pneumonia far less frequently than are dogs.

Respiratory disease is common in dogs, and can result in a constellation of clinical signs. These clinical signs range from those that are irritating to owners (e.g., nasal discharge, stridorous panting, chronic hacking cough) to those which are life-threatening and require immediate medical attention.

There are several ways to obtain samples from the airways and lower respiratory tract for cytologic evaluation and microbiologic culture. In general, samples should be handled quickly since respiratory epithelial cells degrade with some rapidity after retrieval, and samples should be handled gently to avoid damaging cell membranes.

The pulmonary system is complex with various anatomical structures performing highly specialized functions. When evaluating the system it is useful to examine each structure for its unique function and associated potential complications. Physical assessment and monitoring tools such as pulse oximetry and arterial blood gas analysis are used to localize respiratory problems and guide treatment which may include supplemental oxygen therapy, appropriate drugs or pulmonary physiotherapy.