NREMT Pharmacology & Medication Administration 2 — Questions and Answers

Question 1: A patient is experiencing an allergic reaction with urticaria (hives) and mild wheezing but has a blood pressure of 110/70 mmHg and is alert. Per protocol, which medication would be MOST appropriate?

Epinephrine 1:1,000 IM (Correct answer)
Diphenhydramine (Benadryl) per protocol
Nitroglycerin sublingual
Albuterol nebulizer

Correct answer: Epinephrine 1:1,000 IM

Anaphylaxis with any systemic symptoms (wheezing) should be treated with epinephrine 1:1,000 IM as the first-line treatment, even if blood pressure is currently maintained. Antihistamines are adjuncts, not primary therapy.

Anaphylaxis is a life-threatening systemic allergic reaction mediated by IgE and requires epinephrine as the first and most critical treatment. The presence of both dermatological symptoms (hives/urticaria) and respiratory symptoms (wheezing) meets the criteria for anaphylaxis, even in the absence of hypotension. Epinephrine counteracts the pathophysiological effects of anaphylaxis through multiple mechanisms: alpha-1 agonism causes vasoconstriction reversing hypotension and decreasing mucosal edema; beta-1 agonism increases heart rate and contractility; beta-2 agonism bronchodilates and inhibits mediator release. The correct formulation for intramuscular administration is epinephrine 1:1,000 (1 mg/mL), administered in the anterolateral thigh. The 1:10,000 concentration (0.1 mg/mL) is for intravenous use in cardiac arrest. Administering the wrong concentration can result in a 10-fold dosing error. Standard adult IM dose is 0.3-0.5 mg (0.3-0.5 mL of 1:1,000). Diphenhydramine (an antihistamine) and albuterol (a bronchodilator) are adjunct medications that address individual symptoms but do not reverse the underlying systemic reaction the way epinephrine does. They should be given after epinephrine, not instead of it. Delaying epinephrine to trial antihistamines first significantly increases mortality risk in anaphylaxis.

Question 2: A patient with chest pain is prescribed nitroglycerin but states his blood pressure is 'usually low.' The EMT checks the blood pressure and finds it is 88/60 mmHg. What should the EMT do?

Administer the nitroglycerin since the patient is prescribed it
Withhold nitroglycerin because the blood pressure is below the safe threshold (Correct answer)
Administer nitroglycerin and then give fluids to compensate
Contact medical direction and administer nitroglycerin while awaiting callback

Correct answer: Withhold nitroglycerin because the blood pressure is below the safe threshold

Nitroglycerin causes vasodilation and reduces preload. Administering it to a hypotensive patient (systolic BP below 90 mmHg) can cause severe hypotension, cardiovascular collapse, and death. It is absolutely contraindicated.

Nitroglycerin is a vasodilator that works primarily by increasing venous capacitance (reducing preload) and, at higher doses, dilating coronary and systemic arteries. These mechanisms are therapeutic in patients with adequate blood pressure — reducing myocardial oxygen demand and improving coronary perfusion. However, in a patient who is already hypotensive, further reduction of preload and systemic vascular resistance can cause cardiovascular collapse. The established contraindications to nitroglycerin administration include: systolic blood pressure below 90-100 mmHg (check local protocol for exact threshold), use of phosphodiesterase-5 inhibitors (Viagra, Cialis, Levitra) within 24-48 hours, right ventricular infarction (ST elevation in leads V1 and right-sided leads), and severe tachycardia or bradycardia. Patients with right heart infarctions are particularly dependent on preload — nitroglycerin can precipitously drop their cardiac output. For this patient with an 88/60 mmHg blood pressure, withholding nitroglycerin is the correct action. Treatment should focus on oxygen administration, cardiac monitoring, IV fluid administration for hemodynamic support if within scope, and urgent transport to a cardiac capable facility. Medical direction should be contacted for guidance on pain management alternatives.

Question 3: Activated charcoal is indicated for which of the following ingestion scenarios?

A patient who ingested gasoline 30 minutes ago
A patient who ingested acetaminophen (Tylenol) 45 minutes ago and is alert and able to swallow (Correct answer)
A patient with altered mental status who ingested sleeping pills
A patient who ingested a caustic cleaning agent

Correct answer: A patient who ingested acetaminophen (Tylenol) 45 minutes ago and is alert and able to swallow

Activated charcoal works by adsorbing the toxin in the GI tract. It is most effective when given within 1 hour of ingestion. An alert patient who can protect their airway and ingested a charcoal-responsive substance (like acetaminophen) is the appropriate candidate.

Activated charcoal is a fine black powder that adsorbs many toxins in the gastrointestinal tract, preventing their absorption into the bloodstream. It is most effective when administered within 30-60 minutes of ingestion, before significant absorption has occurred. However, it has important contraindications and limitations. Activated charcoal is contraindicated in: altered mental status or inability to protect the airway (aspiration risk), ingestion of caustic substances (acids, alkalis) as it causes further mucosal damage and interferes with endoscopic visualization, ingestion of hydrocarbons (petroleum products) due to aspiration risk with high hydrocarbon content, and substances not adsorbed by charcoal (iron, lithium, cyanide, alcohols, heavy metals). For gasoline ingestion, the hydrocarbon risk of aspiration from vomiting outweighs potential benefit. Acetaminophen is well-adsorbed by activated charcoal, and an alert patient at 45 minutes post-ingestion is an ideal candidate. Dosing is typically 1 g/kg (adult: 25-100 g) mixed in water. Administration must be per medical direction — not all EMS systems carry activated charcoal or have protocols for its field use. Always contact poison control (1-800-222-1222) and medical direction before administration.

Question 4: A patient uses an albuterol inhaler and requests assistance. What does albuterol do in the body?

Constricts bronchioles to reduce mucus production
Dilates bronchioles by relaxing bronchial smooth muscle (beta-2 agonism) (Correct answer)
Reduces inflammation in the airways
Increases cardiac output by stimulating beta-1 receptors primarily

Correct answer: Dilates bronchioles by relaxing bronchial smooth muscle (beta-2 agonism)

Albuterol is a selective beta-2 adrenergic agonist that relaxes bronchial smooth muscle, causing bronchodilation. This reverses bronchospasm and reduces airway resistance in asthma and COPD.

Albuterol (salbutamol) is a short-acting beta-2 adrenergic receptor agonist (SABA) that works by binding to beta-2 receptors on bronchial smooth muscle, causing relaxation and bronchodilation. This increases airway diameter, reduces resistance to airflow, and improves ventilation. It is the primary rescue medication for acute bronchospasm in asthma and COPD. The beta-2 selectivity of albuterol means it primarily affects the lungs with less cardiac stimulation than non-selective beta-agonists. However, at higher doses, albuterol can cause systemic beta-1 and beta-2 effects: tachycardia, tremor, hypokalemia (from intracellular potassium shift), and mild vasodilation. These are expected pharmacological effects, not adverse reactions per se, but EMTs should be aware of them, particularly the tachycardia, which can be alarming in an already respiratory-distressed patient. The standard inhalation dose via nebulizer is 2.5 mg in 3 mL normal saline, administered over 5-10 minutes. Via metered-dose inhaler (MDI), the dose is typically 2 puffs with a spacer. Administration requires medical direction authorization in many systems. The EMT should reassess breath sounds and respiratory status after administration and document the response. Lack of improvement after 2-3 treatments suggests severe exacerbation requiring ALS intervention and urgent transport.

Question 5: Which of the following is the correct route and location for epinephrine auto-injector administration?

Subcutaneous injection into the abdomen
Intramuscular injection into the anterolateral thigh (Correct answer)
Intravenous injection into the antecubital fossa
Intramuscular injection into the deltoid muscle

Correct answer: Intramuscular injection into the anterolateral thigh

Epinephrine auto-injectors (EpiPens) are designed for intramuscular injection into the anterolateral thigh (outer mid-thigh), which provides the fastest absorption. They can be administered through clothing.

Epinephrine auto-injectors (such as EpiPen and Auvi-Q) are designed to deliver a fixed dose of epinephrine 1:1,000 via intramuscular injection. The preferred administration site is the anterolateral thigh — the outer, middle third of the thigh — because this site provides rapid absorption through the highly vascular muscle tissue. Studies have shown that absorption from the anterolateral thigh is faster than from the deltoid muscle or subcutaneous sites. A key advantage of auto-injectors is that they can be administered through clothing (no need to remove pants or expose the skin), which saves critical time in anaphylaxis management. The injection should never be made into the buttocks (risk of sciatic nerve injury and slower absorption), into veins (can cause severe hypertension and arrhythmias), or into fingers and hands (can cause ischemia from vasoconstriction). Adult auto-injectors deliver 0.3 mg of epinephrine; junior auto-injectors deliver 0.15 mg for smaller children (approximately 15-30 kg). After injection, the device should be held in place for 10 seconds to ensure full medication delivery, then removed and the injection site rubbed. The used auto-injector should be transported to the hospital with the patient — the physician will want to confirm the dose given. Reassess in 5-15 minutes; a second dose may be indicated if symptoms do not improve.

Question 6: A patient with known COPD is in severe respiratory distress. The MOST appropriate oxygen delivery device and flow rate is:

Nasal cannula at 2 L/min to avoid eliminating the 'hypoxic drive'
Non-rebreather mask at 15 L/min regardless of SpO2
Titrate oxygen to maintain SpO2 of 88-92%, using the appropriate device for the required flow rate (Correct answer)
No supplemental oxygen since COPD patients should not receive oxygen

Correct answer: Titrate oxygen to maintain SpO2 of 88-92%, using the appropriate device for the required flow rate

Modern guidelines recommend titrating oxygen in COPD to maintain SpO2 88-92%. Excessive oxygen can cause adverse outcomes (V/Q mismatch, Haldane effect), while too little is also dangerous. Match the delivery device to the required flow rate.

The concept of the 'hypoxic drive' — the idea that COPD patients breathe based on low oxygen rather than high CO2, and that supplemental oxygen will cause them to stop breathing — is oversimplified and has led to under-treatment of hypoxic COPD patients in the past. Modern evidence shows that the hypoxic drive is rarely the primary concern; however, excessive oxygen supplementation in COPD patients can cause adverse effects through two mechanisms: the Haldane effect (O2 displaces CO2 from hemoglobin, increasing dissolved CO2) and V/Q mismatch (O2 causes vasodilation in poorly ventilated lung segments, worsening dead space). Current guidelines (BTS, ERC) recommend targeting SpO2 of 88-92% for COPD patients with known or suspected type 2 respiratory failure (CO2 retainers). For patients in severe distress with SpO2 below 85%, appropriate oxygen supplementation to reach this target is critical and takes precedence over theoretical concerns about hypoxic drive. Never withhold oxygen from a critically hypoxic COPD patient. In practice, this means starting with a moderate flow device (Venturi mask at 24-28% delivers precise FiO2) and titrating based on SpO2 response. A non-rebreather at 15 L/min can deliver up to 90% FiO2 and is appropriate for initial resuscitation in a severely hypoxic patient, with reassessment and weaning once SpO2 reaches the target range. Always reassess SpO2 after any change in oxygen delivery.

NREMT Pharmacology & Medication Administration 2

A patient is experiencing an allergic reaction with urticaria (hives) and mild wheezing but has a blood pressure of 110/70 mmHg and is alert.
Per protocol, which medication would be MOST appropriate?