Serotonin Syndrome

27yF comes in jittery and diaphoretic. A friend says they were trying to get high on molly and percoset, but they ran out of percoset and so took robitussin instead.

Etiologies for SS

1 - adding a serotonergic agent

2-  increasing the dose of a serotonergic agent

3 - with therapeutic doses of a serotonergic agent...

Serotonergic agents - SSRIs, SNRIs, TCAs, MAOIs, MDMA, DXM, many others

Think of the signs and symptoms as synaptic serotonin overdose in the CNS and PNS (autonomic and somatic). This condition is often missed so check out the Hunter criteria below.

1 - AMS - agitation, restlessness

2 - Autonomic instability - tachy, htn, mydriasis, diarrhea, diaphoresis

3 - Neuromuscular hyperactivity - hyperreflexia, tremor, rigidity and clonus (greater in the lower extremities! [watch the video])

Treatment (supportive) - stop serotonergic medications

1 - benzos

2 - cooling

3 - cyproheptadine (no proven effect,  antihistamine with antiserotonergic effects)

 

This girl stopped taking her ativan to show people on youtube what serotonin syndrome looks like.

Sources

Rosh Review

Medscape: Serotonin syndrome

LIFTL: Serotonin syndrome

BMJ: Serotonin syndrome

Black Widow Envenomation

Black widow spiders can be identified by the yellow-red hourglass shape on their belly. They carry a venomous neurotoxin that can progress from local to severe, diffuse muscle cramping (even mimicking acute abdomen). The venom accomplishes this by releasing acetylcholine and norepinephrine at the synapse. As you can imagine, with increased neurotransmitter release, you will get sympathomimetic hyperactivity - diaphoresis, restlessness, ptosis, htn, tachycardia.

Analgesia and muscle relaxation is the treatment with opioids and benzos. In severe cases or patients with significant comorbidities, you can give antivenin. Be cautious as 25% of pts will develop anaphylaxis from antivenin and the syndrome is otherwise self-limited. 

 

 

Other fun facts:

Alaska is the only state that does not have black widow spiders.

Female spiders sometimes eat the male after copulation (hence the name).

Sources

Rosh Review

Medscape: Widow Spider Envenomation

Retropharyngeal Abscess (RPA)

22yM bounces back 3 days after an ED fishbone extraction with fever and sore throat. His neck is rigid in extension.

The retropharyngeal space is between the posterior pharynx and the prevertebral space (see picture). You can feel a mass and elicit tenderness by rocking the trachea side-to-side (tracheal rock sign). Other symptoms - neck stiffness and pain, dysphagia, "duck-like" voice (cri du canard).

Three ways to get an RPA-

1- Suppuration of lymph nodes from local infection (pharyngitis, etc), MCC in children and the majority of cases

2- Direct penetration from trauma (fishbone, EGD)

3- Extension of local purulence from vertebral osteomyelitis, Ludwig's

You will get a CT w/contrast on these patients, but a quicker diagnosis can be obtained with a lateral soft tissue neck x-ray during inspiration and slight neck extension. There will be a widened retropharyngeal space at C2-C4. Or do an ultrasound!!!

Treatment, like always, starts with the airway. Think about fiberoptic intubation to avoid abscess rupture. Then, order IV abx for mixed flora (clinda, cefoxitin, unasyn) and consult ENT for I&D.

 

Sources

Rosh Review

Clinical Gate: Airway imaging

WikiEM: RPA

Pediatric EM Morsels: RPA3

Medbullets: RPA