Cardiac dysrhythmia management & pacemakers LATEST APRIL 2023

Cardiac dysrhythmia management & pacemakers LATES T APRIL 2023 Cardiac dysrhythmias − Students to review slides 4 -29 prior to class: this content will not be covered in NUR 4120 − Normal sinus rhythm • Answers to evaluation of rhythm will always be within normal limits • Rate: 60 -100bpm Sinus node dysrhythmias − Sinus bradycardia • HR < 60 bpm • Sinus node creates impulse at slower than normal rate • Characteristics of NSR but a slower rate − Etiology: sinus bradycardia • Sleep • Athletic training • Hypothyroidism • Vagal stimulation ▪ Vomiting, suctioning, pain • Medication ▪ CCB (decrease HR/BP) , amiodarone, beta -blockers • Increased intracranial pressure • CAD/Acute MI • Hypoxemia • Altered mental status • Acute decompensated heart failure − Sinus bradycardia: clinical manifestations and management • Clinical manifestations: ▪ SOB altered LOC ▪ Hypotension ▪ EKG changes (ST segment changes PVC’s) • Management: ▪ Resolve causative factors ▪ Atropine 0.5 mg IV every 3 -5 minutes  Maximum dose of 3 mg  Atropine w on’t work on a patient with a heart transplant ▪ Emergency transcutaneous pacing ▪ Catecholamines − Sinus tachycardia • HR: 100 -120 • Sinus node creates impulse at faster than normal rate • Does not start or stop suddenly − Etiology: sinus tachycardia • Physiologic stress ▪ Acute blood loss, anemia ▪ Shock ▪ Hyper/hypovolemia ▪ Heart failure ▪ Pain ▪ Hypermetabolic states ▪ Fever ▪ Exercise ▪ Anxiety • Medications ▪ Catecholamine ▪ Atropine ▪ Stimulants (caffeine, nicotine) ▪ Illicit drugs (Ecstasy, cocaine) − Sinus tachycardia: clini cal manifestations and management • Clinical manifestations ▪ Decreased filling time of heart  Reduces cardiac output → Syncope → Hypotension → Acute pulmonary edema (assess lung sounds, diff. breathing) • Management ▪ Abolish the cause ▪ Synchronized cardioversion (hemodynamic instability) ▪ Vagal maneuvers → recharges SA node ▪ Adenosine (only for narrow QRS) ▪ Narrow QRS?  Beta -blockers (rare)  Calcium -channel blockers (rare)  Adenosine ▪ Wide QRS?  sotalol, amiodarone ▪ Increased fluid/sodium (POTS ) postural orth ostatic tachycardia Atrial dysrhythmias − Atrial flutter • Conduction defect in the atrium , filling time is affected , risk = coagulation • Creates atrial rate between 250 -400 times/minute (ventricular rate 75 -150) • Not all impulses conducted to ventricle: therapeutic block at AV node • 2:1, 3:1, 4:1 • Regular atrial activity • P wave = “saw tooth” appearance • HR > 100 bpm ▪ “uncontrolled” • HR > 150 bpm ▪ “rapid ventricular rate” − Etiology: atrial flutter ** • COPD • Pulmonary HTN • Valvular disease • Thyrotoxicosis • Open heart surgery − Atrial flutter: clinical manifestations and management • Clinical manifestations: ▪ Chest pain ▪ Dyspnea ▪ Hypotension • Management: ▪ Electrical cardioversion for unstable patient ▪ See treatment for atrial fibrillation ▪ Medications to slow the ventricular response: