Cardiology & Resuscitation Flashcards

A 62-year-old male presents with substernal chest pain. A 12-lead EKG reveals ST-segment elevation of 3 mm in leads II, III, and aVF. Which coronary artery is most likely occluded, and what is a primary prehospital treatment goal?

Answer: Right Coronary Artery (RCA); Rapid transport to a PCI-capable facility.

ST elevation in leads II, III, and aVF indicates an inferior wall myocardial infarction, which is most commonly caused by an occlusion of the Right Coronary Artery (RCA). The primary goal for a STEMI patient is rapid reperfusion, making immediate transport to a hospital with percutaneous coronary intervention (PCI) capabilities essential to minimize cardiac muscle damage.

According to the most recent AHA guidelines, what is the target range for oxygen saturation (SpO2) in an adult patient who has achieved Return of Spontaneous Circulation (ROSC) after cardiac arrest?

Answer: 92% - 98%

After ROSC, both hypoxia and hyperoxia can be harmful, potentially causing secondary brain injury due to the formation of oxygen free radicals. The American Heart Association (AHA) guidelines recommend titrating oxygen to maintain an SpO2 between 92% and 98% to avoid these complications.

A 45-year-old female presents with a regular, narrow-complex tachycardia at a rate of 180/min. She is pale, diaphoretic, and has a blood pressure of 78/50 mmHg. Which of the following is the most appropriate initial intervention?

Answer: Perform synchronized cardioversion.

The patient is exhibiting clear signs of instability (hypotension, pallor, diaphoresis) due to the tachyarrhythmia. In cases of unstable tachycardia, immediate synchronized cardioversion is the indicated treatment to rapidly restore a stable rhythm and improve perfusion. While Adenosine is appropriate for stable SVT, the patient's instability makes electrical therapy the priority.

You are treating an 80-year-old male with a history of a previous MI who is complaining of dizziness and weakness. His heart rate is 38/min, BP is 82/54 mmHg, and an EKG shows a third-degree AV block. Atropine has been administered with no change in his condition. What is the most appropriate next step?

Answer: Initiate transcutaneous pacing (TCP).

This patient has symptomatic bradycardia (dizziness, weakness, hypotension) caused by a third-degree AV block. Atropine is often ineffective for high-degree blocks (Mobitz II or third-degree) because the block is typically below the level of the AV node where atropine acts. The next indicated step in the ACLS algorithm for unstable bradycardia unresponsive to atropine is to initiate transcutaneous pacing.

When assessing an unresponsive patient with a Left Ventricular Assist Device (LVAD), which finding is considered normal and should NOT be misinterpreted as a sign of poor perfusion or death?

Answer: A loud, continuous humming sound over the precordium.

LVADs are continuous-flow pumps, which often results in a non-pulsatile state. Therefore, palpable pulses and standard blood pressure readings may be absent even with adequate circulation. A continuous humming or whirring sound is the normal operating sound of the LVAD motor and is a key indicator that the device is functioning.

You are leading the resuscitation of a 6-year-old child in ventricular fibrillation. Which of the following is the correct initial energy dose for defibrillation using a manual defibrillator?

Answer: 2 J/kg

According to Pediatric Advanced Life Support (PALS) guidelines, the initial recommended energy dose for pediatric defibrillation is 2 Joules per kilogram (J/kg). If this is unsuccessful, subsequent shocks can be increased to 4 J/kg, and then up to a maximum of 10 J/kg or the adult dose. Weight-based dosing is critical for safety and efficacy in children.