Tag Archives: anesthesia

Myth Buster: Egg allergies and Propofol

18 Jun

 

Bottom line: there is no confirmed report of propofol-induced anaphylaxis in egg-allergic patients.

 

Propofol is made up of an oil water emulsion using soybean oil (10%) and egg lecithin (1.2%).

 

Lecithin (from the Greek lekithos, which means egg yolk) is a purified phosphatide found in egg yolk.

 

Egg allergy is most common during childhood and is usually outgrown by adulthood. The five major allergens that have been characterized originate from the egg white. Chicken serum albumin is the major allergen that has been described from the egg yolk.

 

The cases documented of anaphylaxis that have been associated with propofol were never followed with formal skin testing.

 

Now that we are on the topic… what about allergies to soy? Should you be worried that patients with soy allergies will have anaphylaxis to propofol?

 

Refined soy oil, such that is used to make propofol, is safe for people with soy allergy because the allergenic proteins are removed during the refining process.

 

Source: Anesthesia in the patient with multiple drug allergies: are all allergies the same? Current Opinion in Anaesthesiology. June 2011. Issue: Volume 24 (3), p 320-325; picture

 

Submitted by K Estes.

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great visual: hematoma block

11 Sep

if you have 10 seconds only, check out this great picture for those visual learners from an old EP Monthly article:

 

if you have more than 10 seconds to spare…

 

HEMATOMA BLOCK (check out this previous post for another nice review):

  • draw up 10 cc or so of 1-2% lidocaine
  • clean site
  • insert needle into fracture spot, confirmation by
    • ultrasound
    • needle “falls” into the fracture with loss of resistance
    • flash of blood
  • infiltrate 8-12 cc lidocaine
  • wait 5-10 minutes
  • reduce away

 

References: EP monthly article; picture

foreign body (sensation) in throat, but no NP scope?

3 Sep

TRY THE GLIDE-SCOPE (or other video laryngoscopes)

recent post from The Procedural Pause covers the procedure for checking for and/or removing a fish bone using a Glidescope assist:

HIGHLIGHTS:

Anesthetize the throat (e.g. benzocaine spray, viscous lidocaine)

Feel, ask the patient to localize (if they can)

Take a look with the Glide-Scope (slowly)

Retrieve the foreign body with long hemostats/forceps (?suction)

Follow-up with ENT 24-48 hrs

Others have gone there before…

anesthesia article on 26 patients with impacted crycofaringeal upper esophageal FB, after unsuccessful removal attempts in the ENT or GI unit

  • under concious sedation, 17/26 foreign bodies identified & removed
  • the other 9/26 needed rigid endoscopy in general anesthesia/intubation, but had FBs impacted beyond the upper esophageal sphincter

cadaver study, with inexperienced 1st-year EM residents retrieving foreign bodies with Mac’s & Glide-Scopes

  • better 1st attempt removal with Mac’s
  • faster with Magill forceps (has a bend) than Sponge forceps (straight)
  • possible limitation: Glide-Scope’s bigger than the standard Mac, limited oropharynx space & maneuvering, especially for 1st years with little airway experience

BOTTOM LINE:

Working at a few hospitals lately without a readily available NP scope, which makes evaluation of a patient with a pharyngeal foreign body (sensation) more challenging.  

Many EDs now have a video laryngoscopes as an airway adjunct, and was wondering if that might be useful tool to look for a foreign body, in absence of an NP scope.  Nice to know some other folks have gone there before, with some success.

Along with DL visualization, add it (GlideScope/video visualization) to the toolbox.  

References: procedural pause post (picture’s from here); anesthesia article; cadaver article

Post LP Headache

25 Jun

90% headaches within 3 days.

Postural.

Keep in mind that could be intracranial hemorrhage causing repeat headache.

 

The incidence is:

  • ∼40% with a 22G needle;
  • 25% with a 25G needle,
  • 2%–12% with a 26G Quincke needle,
  • <2% with a 29G needle. (i.e. smaller is better)

Risk factors for post–lumbar puncture headache 

  • use of a large needle size (>22 gauge),
  • use of a cutting (Quincke) needle,
  • multiple attempts,
  • failure to replace the stylet when withdrawing the needle.

 

Prevention:

Smaller needles (if possible, may need at least 22G to measure pressure, obtain CSF).

Orientation – perpendicular orientation of bevel (‘split the fibers’)

 

Treatment:

Caffeine (300-500mg PO or IV daily or BID)

Blood patch

 

Submitted by J. Andrick.

 

References: Post‐dural puncture headache: pathogenesis, prevention and treatment. Turnbull DK. Brit J AnesPostgrad Med J. 2006 Nov;82(973):713-6.Post lumbar puncture headache: diagnosis and management. Ahmed SV, Jayawarna C, Jude E.; picture

 

failed airway algorithm

20 Feb

cribbed right from the emcrit blog post on the Shock Trauma Center Failed Airway Algorithm

check it out. sums up what we usually do. 

personally, i’m a bougie fan. lately, been giving more consideration to using the LMA as a rescue airway for a difficult intubation. take a look, form your own favorites.

BOTTOM LINE:

have a plan A, plan B, and plan C (at least).

 

References: emcrit post

quick ER math: propofol

16 Nov

QUICK HITS:

lipid soluble anesthetic agent

rapid onset (<1 min)

peak effect (6-7 min)

brief duration (5-10 min)

side effects: respiratory depression, hypotension

 

DOSING FOR PROCEDURAL SEDATION:

0.2-1.0 mg/kg

0.2 mg/kg * average 70kg person = 14 mg

1 mg/kg * average 70kg person = 70mg

 

DOSING FOR INFUSION/DRIP:

5-125 mcg/kg/min

 

PERSPECTVE:

1000 mcg = 1 mg

if you start a propofol drip at 5 mcg/kg/min, on an average 70kg person

5 mcg/kg/min * 70kg = 350mcg/min    ~    slow pushing 0.35 mg propofol every minute

~ slow pushing 3.5 mg propofol every 10 minutes

25 mcg/kg/min = 5 * 5 mcg/kg/min

~ slow pushing 17.5 mg propofol every 10 min

125 mcg/kg/min = 5 * 25 mcg/kg/min

~ slow pushing 8.75 mg propofol every minute

~ slow pushing 87.5 mg propofol every 10 min

 

 

BOTTOM LINE:

  • propofol infusion doses are relatively small compared to most procedural/induction doses
  • barring side effects (e.g. hypotension), don’t be afraid to titrate up drips to sedation

 

References: Tintinalli’s Emergency Medicine: A Comprehensive Study Guide. 7th Edition; Rosen’s Emergency Medicine. (2010); picture

Difficult Airway Algorithm

24 Sep

Heard AM, Green RJ, Eakins P.

  • Australian anesthesiologists designed an evidence-based difficult airway algorithm and trained their staff in its procedures
  • Training included 1hr “dry lab” using mannequins, plus a “wet lab” using intubated sheep who were being euthanized for medical research

HIGHLIGHTS:
  • First step is always needle cric, because:
    • it is easy to remember,
    • the required equipment is readily accessible,
    • and is a temporizing measure
  • All pathways involve middle step of jet ventilation and stabilization
  • All endpoints involve a cuffed endotracheal device

 

  • Scalpel bougie and neck dissection had the highest success rates (100%).
  • Scalpel bougie was the quickest (39 seconds mean). They observed thousands of these procedures but only reported success rates and time to successful completion for 10.
  • Scalpel bougie is most useful for airways when air cannot be aspirated with needle cric (ie bloody) but external anatomy is still palpable.
  • Melker is their favorite Seldinger technique airway device when compared with 3 others

Submitted by M. Smith.