Topics in this EM Quick Hits podcast
Anand Swaminathan on airway management in angioedema (1:15)
Jeff Perry on Ottawa subarachnoid hemorrhage rule and 6hr CT rule (8:42)
Hania Bielawska on ED breastfeeding myths and misconceptions (21:16)
Rachel Bridwell, Brit Long & Michael Gottlieb on neurologic associations with COVID-19 (29:53)
Justin Hensley on management of spider bites (36:06)
Hans Rosenberg & Heather Murray on management of skin abscesses (44:52)
Podcast production, editing and sound design by Anton Helman
Podcast content, written summary & blog post by Anand Swaminathan, Brit Ling, Hania Bielawska and Anton Helman.
Edited by Anton Helman
Cite this podcast as: Helman, A. Swaminathan, A. Perry, J. Rosenberg, H. Bielawska, H, Long, B. Bridwell, R. Gottlieb M. Hensley, J. Murray, H. EM Quick Hits 19 Angioedema, SAH Decision Tool, Breastfeeding Myths, COVID-19 Neurology, Spider Bites, Skin Abscess Management. June, 2020. https://emergencymedicinecases.com/em-quick-hits-june-2020/. Accessed [date].
Management of Severe Angioedema
- For the crashing patient with severe angioedema consider a Ketamine-Only Breathing Intubation (see KOBI), an alternative to awake intubation using dissociative dose ketamine (in a typical adult 100 mg over 30 seconds), and have a “double set up” with the neck prepared for cricothyrotomy
- For the non-crashing patient with severe angioedema consider an awake intubation with full topicalization and fiberoptic intubation
- Medications for ACEi-associated angioedema such as icatibant, C1 esterase inhibitors and FFP are not evidence based and are generally not indicated
- Consider tranexamic acid (TXA) 1g IV over 10 minutes based on a study of 33 patients in France
Episode 127 – Drugs that work and drugs that don’t – Is there any role for icatibant, C1 esterase inhibitors or FFP for angioedema?
Ottawa Subarachnoid Hemorrhage Rule and 6-Hour Computed Tomography Rule
The Ottawa SAH rule is recommended to assess whether or not a patient who presents with headache can be safely ruled out without any investigations.
Inclusion: GCS 15, ≥15 years old, new severe atraumatic headache, maximum intensity within 1 hour.
Exclusion: Patients with new neurologic deficits, prior aneurysm, prior SAH, known brain tumors, or chronic recurrent headaches (≥3 headaches of the same character and intensity for >6 months).
- Age ≥40,
- Neck pain or stiffness,
- Witnessed loss of consciousness,
- Onset during exertion,
- Thunderclap headache (peaking pain within 1 second),
- Limited neck flexion on examination
The Ottawa SAH rule was shown to have a 100% sensitivity for SAH in its validation, however it was 95% sensitive in the latest implementation study (note that there was only one true SAH miss in this study of a patient with profound anemia)
The Ottawa SAH 6-Hour Computed Tomography Rule is recommended to assess whether or not a patient who fails the Ottawa SAH rule can be ruled out with a plain CT done within 6hrs of headache onset without the need for further investigations (lumbar puncture, CTA).
- Exclusion: 3 or more previous similar headaches (ie, same intensity/character as their current headache) over a period of >6 months (eg, established migraines), confirmed SAH before arrival at study ED, previously investigated with CT and LP for the same headache, papilledema, new focal neurological deficit, previous diagnosis of intracranial aneurysm or SAH, known brain neoplasm, cerebroventricular shunt, headache within 72 hours following a LP, headache described as gradual or peak intensity beyond 1 hour
- Sensitivity = 95%, specificity=100%
- The 6-hour-CT rule resulted in a 13% decrease in LP utilization following a normal early CT (26% vs 39%)
- 5 patients had SAH with the CT reported as normal: two unruptured aneurysms on CTA and presumed traumatic LP (as deemed by the treating neurosurgeon), one missed by the radiologist on the initial interpretation, one dural vein fistula (ie, non-aneurysmal), and one patient with sickle cell anemia with profound anemia (Hb, 63 g/L) with a 3 mm aneurysm
- The Ottawa SAH 6hr rule for CT rule out should not be applied to patients who are known to be anemic with a serum Hb<90 g/L (9g/dL) at the time of the CT head because any blood will appear darker than usual on the CT scan making it more difficult to distinguish blood from brain tissue and hence can be missed on the CT.
The Ottawa Subarachnoid Hemorrhage decision tool on MDcalc
SGEM with Rory Spiegel deep dive into 2020 implementation study
Ottawa Rules app video
ED Breastfeeding Myths and Misconceptions
- Physicians often confuse medication safety in lactation with that in pregnancy, or give overly cautious advice due to a concern for the infant’s safety; however, the vast majority of medications we use in the ED, as well as conditions we encounter, should not preclude ongoing breastfeeding
- Not only can our well-meaning advice to avoid certain medications result in suboptimal care of the breastfeeding woman, suggesting that breastfeeding be interrupted or that a mom should express and dump her breast milk can result in a drop in milk supply and even unintended early weaning
- When feeds are missed or replaced by formula, this can quickly result in less breast milk made by the mom, leading to a vicious cycle of a baby who is more hungry and fussy, who then gets more supplementation, spends less time at the breast, and eventually this can end breastfeeding altogether; other adverse consequences of missed feeds are plugged ducts and mastitis
- The best opioid options for pain control in the breastfeeding mother are fentanyl and morphine; fentanyl levels in breast milk are nearly undetectable after 2 hours, while morphine has a short breast milk half-life, and is poorly absorbed by the child; hydromorphine, oxycodone and codeine are not recommended as hydromorphone has a long breast milk half life, oxycodone concentrates in the breast milk and codeine has an unpredictable metabolism
- CT contrast administered to a breastfeeding mother is generally safe for the infant – the dose of CT iodinated contrast to the infant is less than 0.01% of the maternal dose and is thought to be inconsequential
- Interruption of breastfeeding for 13 hours is required for VQ imaging because of the radioactive isotope; during that time however, the mom can still express her milk, and the milk is safe to feed to the infant once 13h has passed
- Anesthetic medications such as propofol, etomidate, fentanyl and midazolam do not require any interruption in breastfeeding; the safety of ketamine is unknown, although it is likely to be safe, based on the principle of rapid redistribution from plasma
- Breastfeeding is safe for most maternal infections; exceptions include Ebola, smallpox, HIV, rabies, active TB, herpes zoster of the breast
- Consult LactMed for specific medication safety
Drugs and Lactation Database (LactMed)
Dr. Hania Bielawska can be reached at [email protected] for questions regarding safe breastfeeding
Management of Spider Bites
The Recluse and Black Widow spiders are the only two spiders in North America that are venomous to humans each of which have different toxidromes
Recluse spider bites tend to occur indoors, initally be relatively painless, have a necrotoxin that dissolves tissues locally, and is classified into minor loxoscelism (localized skin erythema and edema that resolves spontaneously over 1 week) and cutaneous loxoscelism (the more severe form with cutaneous blisters and/or irregular echymosis and classically the red, white and blue sign – see below – which may develop a necrtotic eschar and heals over 6-8 weeks)
Red, white and blue sign of recluse spider bite with echymotic center, surrounded by ischemic blanching and erythema at the periphery
Treatment involves appropriate wound care and symptomatic treatment with anitrpruritic
Recluse spider bites can rarely cause systemic loxoscelism with hemolysis and myelonecrosis, petechial rash, fever, vomiting, acute renal failure, DIC requiring resuscitation supportive care with blood products
Black Widow spider bites are neurotoxic (acetylcholine mediated) causing intense sudden pain locally or regionally, localized diaphoresis, hypertension, agitation, fever, and can mimic an acute abdomen.
Treatment is supportive; there is an antivenom for black widow spider bites, however there is no evidence of clinical benefit with its use.
None of the authors have any conflicts of interest to declare