19.2 Geriatric Pharmacology

The same milligram that is polite in a 40-year-old can stop an 85-year-old's breathing. Domain 5.C of the August 2026 Board of Certification for Emergency Nursing (BCEN) Certified Flight Registered Nurse (CFRN) outline still owns geriatric pharmacological care after you have named the injuries and medical diagnoses in 19.1. Doses below are typical critical-care teaching. BCEN does not publish a geriatric dose table.

Beers as a way of thinking, not a list to memorize

The American Geriatrics Society (AGS) Beers Criteria name potentially inappropriate medications for older adults. You will not reproduce the tables from memory on the aircraft. You will recognize the pattern: drugs with strong anticholinergic burden, long-acting benzodiazepines, some first-generation antihistamines, sliding-scale insulin used alone, and agents that drop blood pressure or sodium without a current indication.

Polypharmacy is the usual sending bag. Five or more standing medicines raise the chance of a drug–drug or drug–disease interaction. The flight job is not to deprescribe a lifetime overnight. It is to stop the next harmful dose, avoid stacking sedation, and hand the receiving team an honest list.

Kidneys, liver, and "start low"

Glomerular filtration rate (GFR) falls with age even when the serum creatinine still looks "normal." Muscle mass is down, so creatinine underestimates impairment. Dose renally cleared drugs — many antibiotics, low-molecular-weight heparin, gabapentin, morphine's active metabolite — as if the kidneys are older than the chart says. If you do not have a Cockcroft–Gault estimate, assume reduced clearance and choose the conservative end of your protocol.

Hepatic blood flow and phase-I metabolism also slow. Lipophilic drugs have a larger volume of distribution in a body with more fat and less water. The result is a delayed peak, a longer tail, and a second hit of sedation after you have already lifted.

Start low, go slow is the flight version of that physiology:

• Give a smaller first dose of a benzodiazepine or opioid, then wait for the effect.
• Reassess after vibration, after a cabin-altitude change, and after you add a second agent.
• Do not "catch up" three midazolam syringes because the first one was slow.

Older adults have increased sensitivity to benzodiazepines, opioids, and anticholinergics. The same milligram produces more apnea, more delirium, more urinary retention, and more conduction surprise. Diphenhydramine for sleep is an anticholinergic delirium infusion. Treat pain; do not treat the cabin with a hangover antihistamine.

Warfarin, DOACs, and a fall

A fall on warfarin is an intracranial-bleed problem until imaging says otherwise. Note the last dose and any international normalized ratio (INR). Typical receiving reversal is 4-factor prothrombin complex concentrate (PCC) plus vitamin K. That is clinical teaching, not a cabin recipe you invent if your program does not carry PCC.

Direct oral anticoagulants (DOACs) do not have a useful INR. Dabigatran may be reversed with idarucizumab if the receiving hospital stocks it. Factor Xa inhibitors (apixaban, rivaroxaban) may be reversed with andexanet alfa where available; many centers still use 4-factor PCC as a bridge. You will not complete most of those infusions on a rural pad. Your job is to name the agent, the last swallow, the time of injury, and to fly to a hospital that can reverse and operate.

Do not hold launch for a complete reversal you cannot finish. Do not give a little vitamin K and call a DOAC reversed.

RSI doses that drop the pressure

Cut induction, not the paralytic

Usual adult rapid-sequence intubation (RSI) induction doses are often too much (Chapter 7). Propofol is a vasodilator; a full 2 mg/kg in a dry, beta-blocked 80-year-old is a code. Typical teaching is a reduced induction dose — often on the order of 0.5–1 mg/kg propofol, or a reduced etomidate or ketamine induction — labeled here as clinical teaching, not a BCEN number. Etomidate is more blood-pressure stable but still not magic if the patient is empty. Ketamine can drop pressure when catecholamine stores are gone.

Succinylcholine and rocuronium are still neuromuscular blockers you dose to intubate, not to "go easy." Do not underdose the paralytic and then stack induction drug because the jaw was tight. Have push-dose or infusion vasopressors ready before you push induction. Recheck blood pressure after the tube, after the first positive end-expiratory pressure (PEEP), and after climb.

Cabin medication reconciliation

The history lives in the brown bag, not in the sending summary.

• Photograph or list every bottle in the tote: name, dose, last fill, and what the family says was actually swallowed today.
• Ask which pills are as-needed and which were doubled this morning.
• Look for patches (fentanyl, clonidine, scopolamine) on the back and chest.
• Write allergies in the family's words. "Codeine makes her sick" is not an anaphylaxis to fentanyl, but it is not nothing.

If two lists disagree, believe the bottles plus the pharmacy printout plus the family, and tell the receiving team the conflict. You are the last person who can stop a second benzodiazepine before climb.

Use the CFRN practice bank.