Cardiac Notes PDF

Cardiac Tags Vital Signs Blood Pressure: 120/80 mmHg SpO₂: 96-100% Heart Rate: 80 - 100 bpm Respiratory Rate: 12 - 14 rpm MAP: >65 mmHg Definition of Blood Pressure...

Cardiac Tags Vital Signs Blood Pressure: 120/80 mmHg SpO₂: 96-100% Heart Rate: 80 - 100 bpm Respiratory Rate: 12 - 14 rpm MAP: >65 mmHg Definition of Blood Pressure Blood pressure represents the extremes of pressure within the circulation during the cardiac cycle (systolic and diastolic). Systolic (SBP) The pressure on the vessel with the heart in contraction. Diastolic (DBP) The pressure on the vessel with the heart in heart relaxation. Mean Arterial Pressure (MAP) The average arterial pressure throughout one cardiac cycle. MAP = [SBP + 2(DBP) ] / 3 Reads: 3 divided by SBP plus 2x the DBP Blood Pressure Background Emergency providers frequently encounter elevated blood pressure. Reflexively treating elevated blood pressure without context can be harmful. Cardiac 1  Asymptomatic hypertension ~may not require~ immediate aggressive treatment. Hypertensive Urgency It is defined as severely elevated blood pressure without symptoms or end- organ damage. Screening for end-organ damage includes: Serum creatinine Urinalysis Chest X-ray ECG uTox Risk of end-organ damage exists if blood pressure remains elevated. Treatment Control blood pressure within 24-48 hours with PO medication. Discharge reliable patients with follow-up. Urgent follow-up is required for potential medication titration. Oral agents like hydrochlorothiazide (HCTZ) are first-line treatment (see compelling indications- JNC Guidelines) Hypertensive Emergency Occurs with elevated blood pressure and evidence of end-organ damage. BP is usually ≥220/110 Symptoms may include or result in: Mental status changes Intracranial hemorrhage Retinopathy Aortic dissection Cardiac 2  Cardiac ischemia Congestive heart failure Acute renal failure Treatment of Hypertensive Emergency Requires rapid but controlled blood pressure reduction with IV medications. Aim to reduce mean blood pressure by 25% within the first hour. A further decrease to normal levels over 24-48 hours if tolerated. Drugs for Hypertensive Emergencies Gradual lowering of blood pressure to avoid complications. Treatment is tailored according to specific organ damage. Nitroprusside Nitroprusside is a potent vasodilator. Lowers blood pressure in seconds; cessation leads to a rapid return to previous levels. Requires hospitalization in an ICU and intra-arterial pressure monitoring. Warning: Can cause cyanide toxicity Labetalol Labetalol is a combination α and β-blocker. Effective in most hypertensive emergencies, preferred in aortic dissection. Useful in pregnancy and patients with intracranial pathology (hemorrhage or stroke). Hydralazine Hydralazine is a vasodilator primarily used in pregnancy. Increases uterine blood flow. Can cause tachycardia via sympathetic activation Contraindications: ACS, aortic dissection Cardiac 3  Fenoldopam Fenoldopam is useful for patients with renal insufficiency or failure. Alternative to nitroprusside to avoid cyanide toxicity. Increases renal blood flow. It can cause reflex tachycardia. Enalaprilat Enalaprilat is an intravenous ACE inhibitor. Effective in congestive heart failure or stroke as an alternative to nitroprusside. May Cause: Hyperkalemia, elevated LFTs, or angioedema Complication: Must be renally-dosed in ARF/ARI Nicardipine Nicardipine is an IV calcium channel blocker. Beneficial for subarachnoid hemorrhage and ischemic stroke patients. Preserves cerebral perfusion and prevents vasoconstriction. Esmolol an IV β₁-blocker. Suitable for aortic dissection cases. Short-acting and titratable. It is beneficial in intubation-induced hypertension, aortic dissection, STEMI/NSTEMI, VF/VT Note: does not cause reflex tachycardia Should not be used at the same time as a vasodilator Contraindicated in Congestive Heart Failure Hypertensive Emergency Causes Cardiac 4  Ischemic Stroke (CVA) Intracerebral Bleed (ICH) Head Trauma Thyroid Storm Pheochromocytoma Chronic HTN Medication Non-Compliance (Long Term) Hyperaldosteronism (Primary) (Conn’s Syndrome) Cushing Syndrome HELLP Preeclampsia/Eclampsia Sympathomimetic Drugs Cocaine Amphetamine Medication Withdrawal Abrupt Cessation from antihypertensive aka rebound HTN ( usually a BB or clonidine) Presentation Hypertensive Encephalopathy Headache Confusion Nausea/Vomiting Heart Failure LV Dysfunction Acute Pulmonary Edema ACS/AMI Cardiac 5  Acute Kidney Injury/Acute Renal Failure Acute Hypertensive nephrosclerosis Microscopic Hematuria Elevated ↑ Cr Problem: Antihypertensive Tx ➞ usual worsening renal function First Line: Fenoldopam Vascular Emergency Aortic Dissection Aortic Aneurysm/Rupture Treatment Goal To reduce the MAP by 25% within the first hour Typically: