The male in the clinical vignette is experiencing symptoms of tetanus (neck rigidity, laryngospasms, dysphagia, and risus sardonicus) which is typically treated with an antibiotic, immunoglobulins targeting tetanospasmin, and a medication to treat the muscle spasms. The long-acting medication described in this scenario is diazepam.
Diazepam is a long-acting benzodiazepine which acts at the GABA-A receptor by increasing the frequency of chloride channel opening therefore decreasing neuron firing. Benzodiazepines are used to treat spasticity, status epilepticus, sedation of violent behavior, anxiety, alcohol withdrawal, insomnia, and as a general anesthethic. Patients can develop dependence especially with shorter-acting ones such as midazolam (shortest-acting at 4 hours), triazolam, and oxazepam.
Richardson and Knight review the treatment and management of tetanus. Treatment consists of administering immunoglobulins to neutralize the tetanus toxin, debriding the wound and giving antibiotics to remove the source of the toxin, giving medications to control the muscle spasms, and providing respiratory support if needed.
Kefer describes a case report of a 61-year-old female who developed tetanus 6 days after puncturing her forearm with a horseshoe pick. On admission, she presented with lock jaw but no dysphagia or respiratory problems and was given tetanus immunoglobulins to neutralize the tetanus toxin. Forty-eight hours later, she developed muscle spasms which were controlled with diazepam and required intubation after she developed respiratory problems. Metronidazole was also administered to eliminate the C. tetani. She was discharged to home forty days after admission.
Figure A demonstrates the laceration of the 15-year-old male in the clinical vignette. Illustration A is an image of a patient with risus sardonicus, the apparent "grinning" that results from abnormal, sustained spasm of the facial muscles.
Answer 1, 3 & 5: These are medications are benzodiazepines that facilitate the GABA-A receptor by increasing the frequency of the chloride channel opening BUT they are short-acting benzodiazepines.
Answer 4: Flumazenil is a competitive antagonist at the GABA-A receptor and is used to treat an overdose with a benzodiazepine.
Richardson JP, Knight AL. The management and prevention of tetanus. J Emerg Med. 1993 Nov-Dec;11(6):737-42. Review.
PMID:8157912 (Link to Abstract)
Kefer MP. Tetanus. Am J Emerg Med. 1992 Sep;10(5):445-8. Review.
PMID:1642709 (Link to Abstract)