POTD: Droperidol

CODE WHITE AMBULANCE TRIAGE. The patient is at imminent risk of harming themselves and your staff. Verbal deescalation was attempted but has failed. Everyone is looking to you for your OK for chemical sedation. You dig your heels in and are about to mutter the first thing that comes to mind: "5 of haldol and 2 of ativan."

But hold up. Because this POTD is about droperidol.

Background: Droperidol is a dopamine antagonist, and is a first generation antipsychotic. It used to be a favorite of ED doctors to treat agitation in the ED and was used for more than 30 years for acute agitation. It was removed from market 20 years ago because of a black box warning due to QTC prolongation and risk of torsades/sudden cardiac death. This was based off a study looking at 273 case reports over a 4 year period. In the deaths reported, the doses used were 25mg-250mg per dose, doses MUCH higher than what we would typically give in the ED for agitation. Adverse cardiac events or death occurred in 10 patients who received a dose less than 2.5mg. From this study, the FDA placed a black box warning on droperidol. Upon further review of these cases by multiple authors, all of these cases had confounding factors that could have accounted for the adverse event. Overwhelming evidence after the FDA black box warning was issued has showed that droperidol is both safe and effective, especially when used at typical dosing for agitation.

Why Droperidol: Comparatively to other sedatives, namely haloperidol, droperidol is more potent, is faster onset, and has a shorter duration. According to Cressman et. al who examined absorption, metabolism, and excretion of droperidol, absorption via IM is near equivalent to IV administration. Onset of action is 3-10 minutes, and peaks at 30 minutes. Duration of effect is 2-4 hours, and effects may last up to 12 hours. Undergoes hepatic metabolism.

In the DORM study, 10mg droperidol IM was compared to 10mg IM Midazolam. Droperidol, compared to Midazolam, reduced the duration of violent behavior (20 min vs 24 min), required less additional sedation (33% vs 62%), and has less respiratory distress among intoxicated agitated patients.

If single agent droperidol is not enough, it was found in a study authored by Taylor et al that combination 5+5 droperidol and midazolam was more effective at sedation than droperidol or olanzapine alone.

Uses: Typical dosing ranges between 5mg -10mg for agitation, and can be administered IM or IV.

In addition, it can be used to treat headaches, vertigo, nausea, and pain, usually at half the agitation dose.

Side effects: Sedation, extrapyramidal effects, hypotension, prolongation of QT interval. Obtain an EKG if possible before administration, but if not possible, can be obtained after if the patient is agitated. Be mindful of using droperidol in the setting of patients with known prolonged QT interval and patients at risk given their medication history (e.g. methadone).

Sources:

https://vimeo.com/180991859

https://pubmed.ncbi.nlm.nih.gov/4707581/

http://www.emdocs.net/droperidol-use-in-the-emergency-department-whats-old-is-new-again/

http://www.emdocs.net/the-art-of-the-ed-takedown/

https://www.tamingthesru.com/blog/2019/4/20/the-return-of-droperidol

https://pubmed.ncbi.nlm.nih.gov/12707137/

https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=147e033d-d997-4ef6-8bb5-a9ba372590b2&type=display

POTD: The Ingested Coin

This POTD is inspired by a common occurrence in the pediatric ED and a question that routinely shows up on board questions.

History: Mom and Dad are spring cleaning the apartment when 1 year old Freddy Boy starts having sporadic episodes of gagging or choking, and has vomited once. Parents report an episode where he looked like he was breathing faster and almost looked like he was struggling to catch his breath, which has since resolved. Mom and Dad panic and bring F.B. to your ED. Physical exam reveals a happy looking kid, vitals WNL, and a benign exam. Nothing in the back of the throat. Normal breath sounds BL. 

As their provider, high on your differential is foreign body ingestion, and you begin your workup.

Background: Children frequently swallow foreign bodies, with coins being the most common. Other objects, such as fish or chicken bones, buttons, marbles, and the dreaded button battery are common (for adults, food boluses are most common, followed by fish bones, coins, fruit pits, pins, and dentures). A patient who has ingested a FB raises the concern- where is the coin? Is it in the esophagus, or the trachea? Has it already been swallowed and now in the stomach? What was the FB? Oftentimes the history can be suspicious for FB ingestion but the point (or object) of ingestion is often not witnessed. 

Whether the coin/FB be in the esophagus or the airway can produce similar symptoms. Patients can be vomiting, have episodes of gagging and choking, stridor, complaining of chest pain, pain in the neck, throat, or upper back, drooling, and an inability to eat.

A lot of those symptoms are fighting words- they're usually how you describe a patient in danger of respiratory distress, and thus the patient with FB ingestion must be assessed with ABCs in mind on initial and repeat assessments.

Imaging:

The most important next step on evaluation for ingestion of moderate to high risk ingestion is to obtain imaging. Obtain a CXR AP and lateral; additionally, a babygram xray can include the chest and abdomen, which can pick up a coin that may have already passed through the esophageal sphincter and is likely on it's way out.

Back to our case. The child has an xray depicting:

https://prod-images-static.radiopaedia.org/images/219249/4b44984b51f84022153d6f2572b60f_jumbo.jpg

This is an example of the coin being in the esophagus. On AP imaging, coins in the esophagus show their face, while objects stuck in the trachea will usually be visible only by its edge. Obtaining a lateral view can often times help you visualize the trachea; a coin stuck in the trachea on lateral view will show you its face.

https://img.grepmed.com/uploads/5385/peds-trachea-coins-esophagus-chestxray-original.jpeg

In the esophagus, objects are most likely to get stuck at the cricopharyngeus muscle (about 75% of the time), at the level of the aortic arch, and the lower esophageal sphincter.

What to do depends on the object swallowed and where it is located. For esophageal FB, if the object is sharp, a single high powered magnet or several magnets, a disk battery stuck in the esophagus, if airway compromise is present or imminent due to mass effect on the trachea, evidence of perforation, unable to manage secretions, or if the point of ingestion is possible to be >24 hours, emergent/urgent endoscopy is needed.

For esophageal objects that don't have these characteristics, definitive intervention such as endoscopy can be delayed up tot 24 hours to allow a chance for the object to pass spontaneously. If past the lower esophageal junction, objects are very likely to pass through the GI tract on their own. If warranted, objects can be be monitored with serial xrays to follow the object on its way out. These benign objects can be expectantly managed, and the asymptomatic patient can be sent with follow up with PMD/GI.

For tracheal objects, such as this coin, in a patient without complete airway obstruction/on the verge of airway compromise, you can provide supplemental O2 if needed, have the parents calm the child if possible, and allow the patient to assume a position of comfort. These patients are likely to need bronchoscopy to remove, and it is important to get your ENT and possibly anesthesia friends involved in the case.

Best,

SD

Sources:

https://www.grepmed.com/images/5385/peds-trachea-coins-esophagus-chestxray

https://radiopaedia.org/cases/ingested-foreign-body-coin-in-oesophagus-3

https://learningradiology.com/archives2008/COW%20313-Coin%20in%20esophagus/coinesophcorrect.htm

https://www.ncbi.nlm.nih.gov/books/NBK430915/

https://www.uptodate.com/contents/foreign-bodies-of-the-esophagus-and-gastrointestinal-tract-in-children

Trauma Tuesday! TEG

What is it?

Thromboelastography, or TEG, is a whole blood viscoelastic test. Without going too deep into materials science, it is a test that tests the viscosity of blood (or it's ability to resist shear flow and strain when a stressor is applied) and its elasticity (which measures blood's ability to be stretched and then return to its original state once the stretch stressor is removed). Put simply, TEG applies these global properties to whole blood and its ability to form a clot under a low shear stress.  

Background: Like a lot of our research for EM and trauma, TEG was first developed in University of Heidelberg in 1948 and first applied in battlefield medicine during the Vietnam war. It was used as an attempt to determine who should get transfusion of blood products on the battlefield. In the next several decades it was used before and during transplant and cardiac surgeries, and now finds its use in EM and trauma as a potential method to identify acute coagulopathies before transfusion and possible surgery.

How does it work? The blood sample is placed into a disposable cup in the in which a detection pin is suspended in the center. The system oscillates the cup around the detection pin, and measures the degree of pin movement as a function over time.

Liquid, non-clotted blood has a low viscosity, and initially the pin passes easily through it as the cup oscillates, producing little to no movement of the detection pin.

As the blood clots, the detection pin meets more resistance as it passes through the blood- leading to a higher amplitude of movement.

As fibrolysis begins, and as the clot breaks up, the pin meets less resistance, and records less changes in its movement.

Measured as amplitude (or movement of the detection pin) vs time, we get something that looks like this:

https://www.wikem.org/w/images/TEG-Legend.png

Legend:

R : Reaction time; time between start of test to fibrin formation. Measurement of clotting factors

K: Kinetics: time to achieve clot strength of 20mm amplitude; dependent on fibrinogen

a: alpha angle; slope of line between R and K; measures speed of fibrin buildup and cross linking, AKA rate of clot formation

TMA: time to maximum amplitude

MA: Maximum amplitude; the max strength of the fibrin clot/stability of the clot; a measure of platelets and fibrin interacting via GP2b and GP3a

LY30: amplitude at 30 minutes, measure of the fibrinolysis phase

How to interpret: Depending on what value may be greater or less than normal, can diagnose coagulopathy and help guide treatment:

http://www.emdocs.net/wp-content/uploads/2016/12/Screen-Shot-2016-12-20-at-10.23.52-PM-300x290.png

https://lh3.googleusercontent.com/proxy/TuLwySE2hYy1o5Cy9aS_JL-5hDiq5kshcStOZV6rOMaD89fznwGAKRrcNCzz_URHsbVYY8vBebAwMxK3AC-xKgUsXgdCJAnmnKuaKuKPZsaHqIywri4e0IHGi9TrLXzx7A_uRospSbjjUkB7Hif03B-p

Advantages + Disadvantages: So why do this over the coag panel we send from the ED? Why not just send the entire coagulation panel as we click off the boxes in our EMR orderset?

TEG uses whole blood in a point of care test to assess platelet function, coagulation, and fibrinolysis. As a point of care test, we can get near immediate information on a bleeding patient so that we may more expeditiously deliver treatment in a potentially unstable patient. 

In cardiac surgery patients, TEG has found its place to detect, monitor, and manage hemostasis. It can be used to guide perioperative bleeding.

In the trauma setting, however, there is mixed and a current lack of high quality evidence to support its routine use over a conventional coag panel. A Cochrane systematic review in 2015 demonstrated insufficient data to compare the accuracy of TEG versus PT and INR as a reference standard in the diagnosis of trauma induced coagulopathy.

In one study examining the reproducibility of TEG measurements and standardization of it as a laboratory test, R time had a large degree of variability and poor correlation with INR. In patients who are on Warfarin, for example, R time may be normal in a TEG study, and thus may miss a potentially significant coagulopathic state. In this situation, INR is still the gold standard. TEG also cannot replace P2Y12 platelet function to guide clopidogrel therapy, D-Dimer to exclude VTE risk, and other thrombophillic diagnostic tests.

But there are several studies suggesting its potential superiority as a fast and reliable point of care test. One study in 2012 by Holcomb et al. showed TEG was better at predicting the need for transfusion of FFP, RBCs, and platelets compared to PT, aPTT, INR, plt count, and fibrinogen in 1,974 trauma patients. Another study performed by Da Luz et al. demonstrated TEG as an effective method to diagnose coagulopathy and predict blood components transfusion and mortality in trauma patients, with the important caveat that there was no significant improvement in patient mortality or morbidity.

There seem to be a growing number of studies advocating for potential use for TEG in the setting of acutely bleeding trauma patient, but there does not yet seem to be a robust foundation of literature at this time to support its routine use. The potential of TEG to provide quick and reliable information is valuable and keeps the hope alive for its viability as a point of care test in the (hopefully) near future. In fact, this POTD mostly covers TEG alone and does not spend much time delving into ROTEM and r-TEG, examples of alternative and developing variations of TEG that continue to improve on the original concept.

Till next time,

-SD

Sources:

https://wikem.org/wiki/Thromboelastography_(TEG)

https://litfl.com/thromboelastogram-teg/

https://www.ncbi.nlm.nih.gov/books/NBK537061/

https://pubmed.ncbi.nlm.nih.gov/24841452/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4206701/

https://pubmed.ncbi.nlm.nih.gov/22868371/

http://www.emdocs.net/thromboelastogram-teg-five-minute-primer-emergency-physician/