Emergency Medical Services Flashcards

A 58-year-old male presents with sudden-onset chest pain radiating to the back, described as 'tearing.' Blood pressure is 180/100 mmHg in the right arm and 140/85 mmHg in the left arm. Which condition is MOST likely, and what is the immediate priority?

Answer: Aortic dissection; avoid thrombolytics and arrange urgent imaging/surgical consultation

The inter-arm blood pressure differential (>20 mmHg) combined with tearing chest pain radiating to the back is classic for aortic dissection. Thrombolytics are absolutely contraindicated as they worsen hemorrhage and mortality. Urgent CT angiography and surgical consultation are the priorities. Antihypertensive therapy (e.g., IV esmolol) may be used to reduce shear forces, but thrombolysis must never be given.

During a mass casualty incident (MCI) involving a chemical agent release, a paramedic notices that multiple patients have SLUDGE symptoms (salivation, lacrimation, urination, defecation, GI distress, emesis). The MOST appropriate initial antidote sequence for severely affected patients is:

Answer: Atropine titrated to dry secretions, followed by pralidoxime (2-PAM) within the therapeutic window

SLUDGE symptoms indicate organophosphate/nerve agent poisoning causing acetylcholinesterase inhibition. Atropine is given FIRST and titrated until secretions dry (not to heart rate), addressing muscarinic effects. Pralidoxime (2-PAM) is given concurrently or immediately after to reactivate acetylcholinesterase before 'aging' occurs. Giving pralidoxime first without atropine is dangerous as it does not immediately reverse the life-threatening hypersecretion and bronchospasm.

A 34-year-old pregnant woman (32 weeks gestation) is in cardiac arrest. CPR has been ongoing for 4 minutes with no ROSC. Which intervention is MOST critical to optimize resuscitation outcomes for BOTH mother and fetus?

Answer: Perform perimortem caesarean delivery within 5 minutes of arrest to relieve aortocaval compression and improve maternal cardiac output

Perimortem caesarean section (PMCS) should be initiated at 4 minutes of arrest (targeting delivery by the 5-minute mark) for a fetus ≥20 weeks gestation. The gravid uterus compresses the inferior vena cava, severely reducing venous return and cardiac output — delivery relieves this obstruction and dramatically improves the success of maternal resuscitation. Full left lateral decubitus impairs effective chest compressions. Deferring until ROSC is achieved is incorrect; PMCS is itself a resuscitative intervention.

A paramedic is treating a patient with tension pneumothorax who has undergone needle decompression at the 2nd intercostal space, mid-clavicular line. Breath sounds remain absent and hypotension persists. The MOST appropriate next step is:

Answer: Perform a second needle decompression at the 4th or 5th intercostal space, anterior axillary line, using a longer needle

Failure of needle decompression at the 2nd ICS MCL is common in muscular or obese patients because standard 14–16G needles (typically 3.25 cm) may not reach the pleural space. Current guidelines recommend the 4th/5th ICS anterior axillary line as an alternative site with a longer needle (≥8 cm) for definitive decompression. Repeating at the same site with the same equipment is unlikely to succeed. IV fluids provide only temporary benefit without relieving the underlying pneumothorax.

In the context of traumatic brain injury (TBI) management in the prehospital setting, which of the following interventions is MOST likely to worsen secondary brain injury?

Answer: Permissive hyperventilation (PaCO₂ ~30 mmHg) maintained prophylactically throughout transport

Prophylactic hyperventilation (maintaining PaCO₂ ~30 mmHg) causes cerebral vasoconstriction that dramatically reduces cerebral blood flow. While brief hyperventilation may be used as a bridge therapy for impending herniation (Cushing's triad), sustained prophylactic hyperventilation causes ischemia and significantly worsens secondary brain injury. Current TBI guidelines target normocapnia (PaCO₂ 35–45 mmHg) and normoxia. The other options — maintaining adequate MAP, using hypertonic saline for herniation, and head elevation — are all evidence-supported TBI interventions.

A patient presents post-resuscitation from ventricular fibrillation with ROSC achieved. The 12-lead ECG shows a LBBB pattern. The patient is hemodynamically stable but remains comatose (GCS 6). Which combination of post-cardiac arrest care elements reflects CURRENT evidence-based practice?

Answer: Targeted temperature management (TTM) at 36°C for 24 hours, emergent coronary angiography regardless of ECG findings, and avoid hypoxia/hypotension

Post-ROSC care bundles include TTM (evidence supports 33–36°C, with 36°C now acceptable per TTM2 trial data) for comatose survivors to mitigate neurological injury. A new LBBB in a post-arrest patient is treated as a STEMI-equivalent, mandating emergent coronary angiography regardless of whether the ECG criteria are 'classic.' Strict avoidance of hypoxia (SpO₂ <94%) and hypotension (MAP <65 mmHg) is mandatory. Deferring angiography until consciousness is inappropriate, and prophylactic amiodarone infusions are not evidence-based in this context.