Sandbox/WCT 1

Identify cardinal findings that increase the pretest probability of wide complex tachycardia ❑ Palpitations ❑ QRS complex > 120 ms ❑ Heart rate > 150 beats/min

Does the patient have any of the following findings that require urgent cardioversion? ❑ Hemodynamic instability ❑ Hypotension ❑ Cold extremities ❑ Peripheral cyanosis ❑ Mottling ❑ Altered mental status ❑ Chest discomfort suggestive of ischemia ❑ Decompensated heart failure

❑ Yes

❑ No

❑ Continue with the complete diagnostic approach below

Prepare the patient for immediate cardioversion and simultaneously do the following: ❑ Maintain patent airway; assist breathing as necessary ❑ Adminster oxygen (if the patient is hypoxemic) ❑ Cardiac monitor to identify rhythm; monitor blood pressure and oximetry ❑ Give IV sedation if the patient is conscious (don't delay cardioversion to sedate the patient) ❑ Consider expert consultation

VT/VF in the form of cardiac arrest Click here for Cardiac arrest resident survival guide

Unsynchronized cardioversion ❑ If a patient has polymorphic VT and is unstable, treat the rhythm as VF and deliver high-energy unsynchronized shocks ❑ Provide an initial shock of 200 Joules ❑ Increase the dose if no response to the first shock (eg, 300 J, 360 J, 360 J)

Synchronized cardioversion

Atrial fibrillation with aberrancy ❑ Provide an initial dose of biphasic cardioversion of 120-200 Joules (Class IIa, level of evidence A) ❑ If the initial shock fails, increase the dose in a stepwise fashion

Arial flutter and other SVTs with aberrancy ❑ Provide an initial dose of biphasic cardioversion of 50-100 Joules (Class IIa, level of evidence B) ❑ If the initial shock fails, increase the dose in a stepwise fashion ❑ If monophasic wave form is used, begin at 200 Joules and increase in stepwise fashion if not successful

Monomorphic VT (regular form and rate) ❑ Provide an initial dose of biphasic cardioversion of 100 Joules (Class IIb, level of evidence C) ❑ If the initial shock fails, increase the dose in a stepwise fashion

❑ After the stabilization of the patient, continue with the complete diagnostic approach below

Characterize the symptoms: ❑ Palpitations ❑ Lightheadedness ❑ Dyspnea ❑ Diaphoresis ❑ Chest discomfort ❑ Shock ❑ Syncope ❑ Seizures ❑ Cardiac arrest Characterize the timing of the symptoms: ❑ Onset ❑ First episode ❑ Recurrent ❑ Duration ❑ Frequency ❑ Termination of the episode ❑ Spontaneous ❑ Medication use ❑ Not terminated

Identify possible triggers: ❑ Infection ❑ Caffeine ❑ Alcohol ❑ Nicotine ❑ Recreational drugs ❑ Hypovolemia ❑ Hyperthyroidism ❑ Hypoxia ❑ Acidosis ❑ Hypokalemia ❑ Hyperkalemia ❑ Hypoglycemia ❑ Hypothermia ❑ Toxins ❑ Pulmonary embolism ❑ Coronary thrombosis ❑ Cardiac tamponade ❑ Trauma

Examine the patient: Vitals ❑ Pulse ❑ Rate ❑ Tachycardia ❑ Rhythm ❑ Regular ❑ Irregular ❑ Strength ❑ Weak ❑ Alternating in strength (atrial fibrillation with aberrancy) ❑ Respiration ❑ Tachypnea ❑ Blood pressure ❑ Hypotension (in hemodynamically unstable patients) ❑ Marked fluctuation of blood pressure (suggestive of AV dissociation in VT) Neck ❑ Canon A waves on examining the jugular venous pressure of the neck (suggestive of AV dissociation in VT) Cardiovascular examination ❑ Auscultation ❑ Heart sounds ❑ Rapid regular or irregular beats ❑ Murmurs (suggestive of valvular diseases) ❑ Variability in the occurrence and the intensity of heart sounds especially S1 (suggestive of AV dissociation in VT) ❑ Inspection ❑ Midsternal incision (sugestive of previous cardiothoracic surgery) ❑ Palpation ❑ Pace maker or ICD are usually palpapable on the left pectoral area

Order labs and tests: ❑ Order and monitor the ECG Perform urgent cardioversion in unstable patients ❑ Chest x ray ❑ Cardiomegaly (suggestive of heart disease) ❑ Pace maker and ICD appear in the x ray ❑ Invasive electrophysiological studies ❑ Electrolytes ❑ Hypomagnesemia ❑ Hypokalemia ❑ Plasma concentration of drugs (eg,digoxin, quinidine or procainamide