Cardiology handbook Flashcards

Question

What are the IV medications for hypertensive emergency?

Answer 1

Labetolol 20mg iv over 2 mins. Repeat 40mg iv bolus if uncontrolled by 15 mins, then 0.5-2/mg/min infusion in D5 (max 300mg/d), followed by 100-400mg po BD Na nitroprusside 0.25-10mg/kg/min iv infusion (50mg in 100ml D5 =500mg/ml, start with 10ml/hr and titrate to desired BP). Check BP every 2 mins still stable, then every 30 mins. Protect from light by wrapping Hydralazine 5-10mg slow iv over 20 mins, repeat q30 mins or iv infusion at 200-300mg/min and titrate, then 10-100mg po 4x a day (avoid in AMI, dissecting aneurysm) Phentolamine 5-10mg iv bolus, repeat 10-20 mins PRN (for catecholamine crisis)

Answer 2

Suspect in patients with chest, back or abd pain and presence of unequal pulses (may be absent) or acute AR Dx: CXR, ECG, cardiac enzymes Transthoracic (not sensitive) + tranesophageal echo Urgent dynamic CT scan, MRA and rarely aortogram Mx 1. NPO, complete bed rest, iv line 2. Oxygen to keep sO2 >90% 3. Book CCU or ICU for intensive monitoring of BP/P. Arterial line on the arm with higher BP 4. Look for life threatening complication: severe HT, cardiac tamponade, massive hemorrhage, severe AR, myocardial, CNS or renal ischemia 5. Medical management: stabilize the dissection, prevent rupture and minimize complication from dissection propogation. It should be initiated before results of confirmatory imaging studies. Therapeutic goals: reduction of systolic BP to 100-120mmHg (mean 60-75mmHg) and target HR of 60-70/min 6. IV labetolol 10mg ivi over 2mins, followed by additional doses of 20-80mg every 10-15 mins (up to max total dose of 300mg) Maintenance infusion: 2mg/min, and titrating up to 5-20 mg/min IV sodium nitroprusside: starting dose 0.25mg/kg/min, increase every 2 mins by 10ugram/min, max dose 8mg/kg/min Use in caution in patient with renal impairmentm limit infusion rate to <3mg.kg/min if eGFR <30ml/min/1.73m2. Diltiazem and verapamil are acceptable alternatives when B blockers are contraindicated (COAD) 7. Contact CTS surgeon for all proximal dissection (Type A) and complicated distal dissection (type B) e.g. shock, renal artery involvement, haemoperitoenum, limbs or visceral ischemia, periaortic or mediastinal haematoma or haemoperitoneum, persistent or recurrent pain

Answer 3

* Clotting time, INR, aPTT, cardiac enzymes, ABG, D-dimer * CXR (usually normal, pleural effusion, focal oligemia, peripheral wedge) * ECG (sinus tachycardia, S1Q3T3, RBBB, RAD, P pulmonale) * TTE +/- TEE; lower limb doppler * CT pulmonary angiogram or spiral CT scan * Ventilation perfusion scan

Answer 4

1. Oxygen to keep sO2>90% 2. Analagsics e.g. morphine iv 2-5mg 3. Haemodynamically insignificant UFH 5000 units iv bolus, then 500-1500 units/hr to keep aPTT 1.5-2.5 x control or enoxaparin 1mg/kg q12h Start warfarin on day 2 to 3:5mg daily for 2 days, then 2 mg daily on 3rd day adjust dose to keep INR 2-3. New oral anticoagulants are alternatives to warfarin Dabigatran: >5 days of a parenteral anticoagulant, then start 150mg bd Rivaroxaban: for initial therapy or transition from parenteral anticoagulant: 15mg bd for 21 days than 20mg daily Apixaban: for initial therapy or transition from parenteral anticoagulant: 10mg bd for 7 days then 5mg bd Haemodynamically significant (no C/I to thrombolytic) * Book ICU/CCU * r-tPA 100mg iv over 2 hours followed by heparin infusion 500-1500 units/hr to keep aPTT 1.5-2.5 control * Consider surgical embolectomy or percutaneous catheter directed treatment if condition continues to deteriorate or contraindication to thrombolytic therapy 4. Consider IVC filter if PE occurred while on adequate anticoagulation or who have absolute contraindications to anticoagulation

Answer 5

* Arrhythmia Symptomatic sinus bradycardia, AV block, tachyarrhythmia (PSVT, Aflutter/Fib, wide complex tachy (VT or aberrent conduction ) * Pump failure: RV/LV dysfunction * Mechanical complications: VSD, mitral regurgitation (cardaic catheterization and repair if unstable (IABP for interim support) * Pericarditis (Dressler syndrome): high dose aspirin, NSAID e.g. indomethacin 25-50mg TDS for 1-2 days. Others: colchicine, paracetamol

Answer 6

Pericardial effusion compressing one or more cardiac chambers and leading to haemodynamic compromise. In acute conditions, the pericardium cannot distend, and its pressure rises markedly with small volume changes Common causes: neoplastic, pericarditis (infective/non infective), uremia, iatrogenic, traumatic, acute pericarditis treated with anticoagulants Dx: clinical --> pericardial effusion associated with haemodynamic compromise SS Tachypnea, tachycardia, small pulse volume, pulsus paradoxus Raised JVP with prominent x descend, Kussmauls sign Absent apex impulse, faint heart sound, hypotension, clear chest

Answer 7

Ix ECG CXR Echo: RA, RV or LA colalpse, distended IVC, exaggerated tricuspid flow increases and mitral flow decreases during inspiration Management Expand intravascular volume: D5 or NS or plasma, full rate if in sock Positive pressure mechanical ventilation avoided because the positive thoracic pressure can further impair cardiac filling pericardiocentesis with echo guidance: apical or subcostal approach, risk of damaging epicardial coronary artery or cardiac perforation Open drainge under LA/GA: permit pericardial biopsy Misdx of cardiac tamponade as congestive heart failure with diuretics/ACEI or vasodilators can be fatal Patients with malignant pericardial effusion resulting in cardiac tamponade stabilized by urgent pericardial drainage --> consult oncologist to determine benefit from surgical pericardiectomy (pericardial window)

Answer 8

high risk category * Patients with prosthetic valve, including transcatheter valve, or a prosthetic material used for cardiac valve repair * Patients with previous infective endocarditis * Congenital heart disease, repaired congenital heart disease Antibiotic prophylaxis for dental procedure Amoxicillin/ampicillin 2g PO or IV (single dose 30-60 mins before procedure) Allergic to penicillin/ampicillin --> clindamycin (600mg PO or IV) Antibiotic prophylaxis for infective endocarditis is not recommended for respiratory/GI/urogenital/skin and soft tissue procedures unless they are performed in the context of infection Established infection with GI or genitourinary tract --> active agent against enterococci Surgical procedures involving infected skin (oral abscesses) --> agent active against staphylococci and b-hemolytic streptococci

Answer 9

* Hypertension: control preop reduces periop ischemia. Evaluate severity, chronicity of HT and exclude secondary HT Severe HT (DBP >110 or SBP >180): elective surgery (better control first), urgent surgery: rapid acting drug to control (B-blocker) * Cardiomyopathy and heart failure: assess severity of systolic and diastolic dysfunction (affect peri op fluid management) HOCM avoid reduction of blood volume, decrease in systemic vascular resistance or decrease in venous capacitance, avoid catecholamines * Valvular heart disease: AS: postpone elective non cardiac surgery (mortality risk around 10%) in severe and symptomatic AS. Need AVR or valvuloplasty AR: careful volume control and afterload reduction (vasodilators), avoid bradycardia MS: mild or mod --> ensure control of HR, severe --> consider PTMC or surgery MR: afterload reduction and diuretic to stabilize haemodynamics before high risk surgery * Prosthetic valve: reduce INR to subtherapeutic range (e.g. INR <1.3), resume normal dose immediately following the procedure Assess risk and benefit of decreased anticoagulation vs periop heparin

Answer 10

Arrhythmia High grade AV blocking: pacing Intravent conduction delays and no history of advanced heart block or symptoms: rarely progress to complete heart block AF: if on warfarin, may discontinue for a few days, ive PCC or FFP if rapid reversal of drug is necessary Vent arrhythmia Simple or complex PVC or non sustsained VT: usually require no Rx except myocardial ischemia or moderately to severe LV dysfunction function Sustained or symptomatic VT: suppressed preop with lignocaine, procainamide or amiodarone Permanent pacemaker * Determine underlying rhythm, interrogate device to etermine threshold, settings and batery status * If pacemaker in rate responsive mode --> inactivated * Programmed to AOO, VOO or DOO mode prevents unwanted inhibition of pacing * Electrocautery avoided; keep as far away from pacemaker ICD or antitachycardia devices Programmed off immediately before surgery and on again post op to prevent unwanted discharge Inappropriate therapy from ICD, suspend ICD function by placing a ring magnet on the device VF/unstable VT: if no or ineffective therapy from ICD and external defib/cardioversion is required, paddles preferably >12cm from the device

Answer 11

1. Beta blockers should be continued in patients undergoing surgery who have been on beta blockers chronically. 2. In patients with intermediate or high risk myocardial ischaemia noted in preoperative risk stratification tests, it may be reasonable to begin preoperative beta blockers. 3. In patients with 3 or more risk factors (e.g. DM, HF, coronary artery disease, renal insufficiency, CVA), it may be reasonable to begin beta blockers before surgery. 4. In patients in whom beta blocker therapy is initiated, it may be reasonable to begin the medication long enough in advance to assess safety and tolerability, preferably > one day before surgery