Cardiac and Respiratory emergencies Flashcards
What are the 4 main categories of cardiac emergencies
-Congestive heart failure (backward failure, forward failure)
-Arrhythmias (tachyarrhythmias, bradyarrhythmias)
-Cardiac tampon are
-Feline aortic thromboembolic disease
When does heart failure become congestive
when failure leads to fluid accumulation (either pulmonary edema, pleural effusion, ascites)
What is seen with backward heart failure and how do left and ride sided HF occur
-Present its breathing difficulty, increased resp rate and effort
-Left sided: caused by either valvular disease or heart muscle disease leading to pulmonary edema
-Right sided: Caused by valvular disease (tricuspid), heart muscle disease or pericardial effusion (tamponade), leads to pleural effusion, ascites
What clinical signs are expected with left sided (backward) failure
-tachypnea, dyspnea, coughing, collapsed, end respiratory crackles, paradoxical breathing, cyanosis if edema severe
What is the treatment for left sided failure
-oxygen
-Furosemide IV (2mg/kg bolus)
-pimobendan for inotropic support
-low level sedation with butorphanol
-drain pleural effusion
What further tests should be done for left sided HF once the patient is more stable
-thoracic ultrasound for pleural effusion, B lines, pericardial effusion
-LA:A ratio
-blood pressure assessment
-ECG (arrhythmia)
-bloods
-thoracic radiographs
-echocardiogram to achieve definitive diagnosis
What clinical signs are present with right sided (backward) failure
-Pleural effusion (paradoxical breathing)
-jugular distension
-ascites
-hepatomegaly
What are the causes of right sided backward HF
-Lung disease- cor pulmonale
-pulmonic stenosis
-tricuspid disease
-heart muscle disease (DCM/HCM)
-pericardial disease (right sided because right side of heart has smaller muscles so it’s easier to compress)
What is the emergency treatment for right sided failure
-thoracocentesis for pleural effusion (dont give furosemide)
-pimo, ballooning depending on cause of failure
-abdominocentesis only if ascites is causing breathing difficulties
-treat concurrent arrhythmias
-cor pulmonale- investigate and treat lung disease
What to expect with forward failure/cardiogenic shock and what are the treatments for it
-can be seen concurrently with backward failure (in DCM for example), may be result of arrhythmia, see low BP and systolic dysfunction on echo
-Treatment: treat backward failure (furosemide), pimobendan, dobutamine (rarely used), treat concurrent arrhythmias (atrial fibrillation, ventricular fib also possible)
What can cause arrhythmias and what are the main concerns of them
-Causes: systemic disease (electrolyte abnormalities, acid-base disorders, hypoxia, sepsis), intrinsic cardiac disease (myocardial disease, AV valve disease)
-Concerns: impact on the ability of the heart to meet the metabolic needs of the tissue, development of a more life threatening rhythm like pulseless VT or VF
What are the groups of anti-arrhythmic drugs and what do they treat
Group 1: sodium channel blockers (example: lidocaine)- treat ventricular arrhythmias (downstairs problems)
Group 2: beta blockers (examples: atenolol, propranolol, esmolol)-treat surpaventricular arrhythmias (upstairs problems)
Group 3: potassium channel blockers (examples: sotalol, amiodarone)- treat ventricular arrhythmias (downstairs problem)
Group 4: calcium channel blockers (example: diltiazem)- treat supraventricular arrhythmias (atrial fibrillation) (upstairs problem)
Why is important to differentiate between sinus tachycardia from a true tachyarrhythmia before treating
Treating/suppressing a sinus rhythm can be fatal, could be keeping animal alive
Which arrhythmia is atrial fibrillation, what will you see on ECG, and how do you treat it
Supraventricular arrhythmia, see lack of p waves and chaotic R-R interval on ECG, treatment with diltiazem (class 4)
What type of arrhythmia is ventricular tachycardia, what is seen on ECG, when should you treat and what should you treat with
Ventricular tachyarrhythmia, 3or more VPCs at high rate on ECG, treat if HR above 180 (dog) or 250 (cat) or if clinically affected, treat with lidocaine (class 1)
