CPD article: Poisons affecting the cardiovascular system

Abstract

Cardiac and cardiovascular function can be affected by numerous substances, including overdose of drugs for cardiac and cardiovascular conditions, drugs used in the management of other diseases, over-the-counter medicines and supplements, foods and natural toxins such as plants. A common cause of tachycardia in dogs is exposure to salbutamol from piercing an asthma inhaler. Cardiac drugs such as beta-blockers and calcium-channel blockers can cause hypotension and disrupt cardiac rhythm. Although severe cases are not common in companion animals, management may be complex, requiring high dose insulin therapy and/or lipid emulsion therapy. The methylxanthines caffeine and theobromine, which are found in foods, and caffeine in supplements, are readily accessible to pets and can cause central nervous system and muscle (including cardiac muscle) stimulation. Animals with pre-existing cardiac disease or those with a mixed cardiotoxic drug overdose are likely to be more at risk of effects after exposure to substances affecting the cardiovascular system. Support of cardiac and cardiovascular function is essential to prevent cardiac injury and maintain tissue perfusion. Specific management depends on the severity of clinical signs and the particular substance involved.