NCLEX-RNReduction of Risk PotentialHard
During a surgical procedure, the anesthesia provider reports the client's end-tidal CO2 is rapidly rising, heart rate is 140 beats/min, and the client's jaw and limb muscles are rigid. Temperature has risen to 39.8°C (103.6°F). Which medication should the nurse anticipate administering immediately?
- AFlumazenil
- BProtamine sulfate
- CNaloxone
- DDantrolene sodium
Show answer & explanationAnswer & explanation
Correct answer: D. Dantrolene sodium
These findings—rising end-tidal CO2, tachycardia, muscle rigidity, and hyperthermia—are the hallmark presentation of malignant hyperthermia, a life-threatening hypermetabolic reaction to certain anesthetic agents. Dantrolene sodium is the specific antidote that halts the hypermetabolic process by inhibiting calcium release in skeletal muscle.
Why the other options are wrong
- A. Flumazenil reverses benzodiazepine sedation, unrelated to this presentation.
- B. Protamine sulfate reverses heparin, not related to this emergency.
- C. Naloxone reverses opioid overdose, not malignant hyperthermia.
Malignant Hyperthermia
A life-threatening hypermetabolic reaction to certain anesthetics/succinylcholine causing muscle rigidity, hyperthermia, and tachycardia.
- Early sign: rising end-tidal CO2 despite stable ventilation
- Presents with muscle rigidity, tachycardia, hyperthermia, tachypnea
- Treatment: stop triggering agent, give dantrolene sodium, cool client
Memory trick: 'Rigid + rising CO2 = Dantrolene to the rescue.'