Non-pharmaceutical fentanyl (NPF) is a major contributor to opioid overdoses and overdose fatality. In certain urban areas such as Vancouver, over 80% of heroin samples contain NPF. For isolated heroin overdose ED patients, they can be safely discharged after brief observation period (~2 hours). However, “safe” observation time for fentanyl is unknown.
Recently, a retrospective study evaluating the safe observation period in 1009 suspected (uncomplicated) fentanyl overdose ED visits (827 unique patients).
Results:
In the field:
In the ED:
Conclusion:
ED physicians frequently utilize modailities such as noninvasive positive pressure ventilation (NIV) and high flow nasal cannula (HFNC) to support and potentially avoid intubation in patients presenting with acute hypoxic respiratory failure. Unfortunately, failure of these measures, resulting in "delayed" intubation, has been associated with increased mortality.1,2
A recent post-hoc analysis of data from a multicenter randomized controlled trial evaluated 310 patients with acute hypoxic respiratory failure managed with supplemental O2 by regular nasal cannula, HFNC, or NIV.3
The following factors were predictive of eventual intubation in the different groups:
Of note, 45% of the 310 patients eventually required intubation, and these patients in general had a higher initial respiratory rate and lower PaO2 at presentation, and were more likely to have bilateral infiltrates on CXR.
Bottom Line: Reevaluate your patients frequently. If RR remains high, P:F ratio remains low, or patient respiratory effort/work of breathing is not alleviated by noninvasive measures, consider pulling the trigger on intubation earlier.
Unsuccessful lumbar punctures (LP) may lead to epidural hematoma (EH) formation at the site of needle insertion which may affect subsequent attempts and lead to no success or a grossly bloody sample. There is no standard definition of a traumatic LP based on CSF red blood cell counts. Gross blood may also be obtained by interrupting the vascular structures outside the spinal canal which would not result in EH formation.
This was a prospective study of children younger than 6 months who had an LP at a single children’s hospital. Post LP ultrasounds were completed by the investigating team and interpreted by a pediatric radiologist. 74 patients were included in the study. 31% of the patients had evidence of a post LP EH. 17% fully effaced the thecal sac which would likely preclude future success at that anatomic site. 25% of patients where the clinician did not feel there was a traumatic attempt had evidence of an EH.The study was not powered to determine the risk factors for EH formation. The study also did not look at any other consequences to EH.
Key points: Point of care ultrasound to evaluate EH and bleeding at the failed LP site my provide useful information for a location of subsequent attempts. Also US to evaluate for bleeding in the spinal canal may help with interpretation of the CSF when a large number of red blood cells are present.
Bradycardias caused by poisoning are due to the toxin's effects on cardiovascular receptors and cellular channels and transport mechanisms and are often refractory to standard ACLS drugs. The most common drug classes responsible for bradycardias are calcium channel and beta blockers and digoxin (cardiac glycosides). Sodium channel blockers, clonidine, and opiates also can cause bradycardias. Antidotes are as follows:
** ILE is recommended only in life threatening poisonings where other accepted therapies have been use first or in cardiac arrest clinical scenarios.
Linezolid, an antimicrobial agent in the oxazolidinone class, often used to cover MRSA and/or VRE, is a reversible MAOI that increases the risk of serotonin syndrome, particularly when administered with other serotonergic agents.
In 2011, the US FDA issued a warning against concomitant use of Linezolid and other serotonergic agents, particularly SSRIs and SNRIs. When use of linezolid is absolutely indicated, an appropriate washout period prior to initiation was recommended.
Based on published reports and retrospective reviews, the incidence of linezolid-associated serotonin toxicity is between 0.54% and 18.2%.
A study published in the Journal of Clinical Psychopharmacology in Oct 2017 examined the incidence of serotonin syndrome with combined use of linezolid and SSRIs/SNRIs compared with linezolid alone and though there was a trend toward increased incidence in patients on SSRI/SNRIs, the authors were unable to find a statistically significant difference.
Several flaws:
-Study was retrospective
-Incidence of serotonin syndrome in both groups was very low: 1/87 (1.1%) in Linezolid + SSRI/SNRI group compared to 1/261 (0.4%) in Linezolid alone group.
-Patients in “Linezolid alone” group were not on SSRIs or SNRIs, but were allowed to be on other serotonergic medications.
Despite this study, there are many (>30) case reports of Linezolid-associated serotonin syndrome in patients taking other serotonergic agents.
Cyproheptadine (the “antidote”) is an H1 antagonist and nonspecific serotonin antagonist. A single case study published in 2016, reported successful use of cyproheptadine for prophylaxis against serotonin toxicity in a patient with schizophrenia, depression, and severe osteomyelitis requiring treatment with linezolid while on fluoxetine.
Bottom Line:
Risk of linezolid-associated serotonin syndrome may be lower than previously thought, however, it is still not recommended for use in patients taking concomitant serotonergic agents without an appropriate washout period.
In case of resistant infection with no other antibiotic treatment options, the risks and benefits of concomitant administration must be weighed seriously and providers must familiarize themselves with and be vigilant in watching for signs/symptoms of serotonin toxicity.
In situations where use of linezolid is unavoidable in patients on concomitant serotonergic agents, prophylactic cyproheptadine may be considered.
Energy availability considers the amount of remaining energy for metabolic processes based on calories takin in with eating and calories burned through exercise or both.
Menstrual dysfunction occurs as a result of low energy availability causing decreased GnRH inhibition and ovarian suppression and decreased estrogen.
Low bone mineral density occurs due to amenorrhea and decreased energy availability. Estrogen limits bone resorption (stimulates calcitonin and renal calcium retention).
This is very important for young girls as by age 12 they have 83% of their total BMD & 95% two years after menarche.
If you see an athlete in the ED with one component of the triad, inquire about the other two. A 15yo athlete with a stress fracture may not realize that her disordered eating, excessive exercise or amenorrhea may by contributing factors and may benefit from follow up with PCP, dietitian, Gyn, etc.
Clonidine, (central alpha-2 receptor agonist) can produce opioid-like toxidrome in addition to its cardiac effects (bradycardia and hypotension). Previous studies have shown that naloxone has variable (~40%) success in reversing CNS/respiratory depression and cardiac effect.
A recent retrospective study (n=51) of pediatric poisoning showed that administration of 5 to 10 mg had improved reversal of clonidine toxicity.
Total of 51 somnolent patients: 5- 10 mg of naloxone reversed 40 patients
There was no adverse effect from naloxone administration.
Repeat administration of naloxone was required in some patients.
Bottom line
In the past couple of weeks, there have been reports from Illinois about patients using adulterated synthetic cannabinoids, resulting in elevated INR and bleeding. To date, there are approximately 70 cases including 3 fatalities. Brodifacoum, a long-acting vitamin K mediated anticoagulant (similar to warfarin) has been identified in 10 cases. Brodifacoum is frequently used as rodenticide.
This week, Maryland Poison Center received our first notification of a patient with bleeding and elevated INR due to suspected adulterated synthetic cannabinoid use.
When evaluating our patient population:
Patient management of suspected cases:
Patient can be discharged when INR < 2 is achieved with oral vitamine K regimen only (without recent FFP infusion).
Review of published cases highlights that most patients are started on a median doses of 100 mg/day (range: 15 - 600 mg) and stabilize on a PO regimen of 50-100 mg/day. Prolonged PO vitamin K course of 2 – 3 months or longer should be anticipated.
Pease call the Maryland Poison Center at 1-800-222-1222 as we are working with the Maryland Department of Health and CDC to track these cases.
Acute on Chronic Liver Failure
25% of U.S. health care spending goes to the 6% of people who die every year. ICUs account for 20% of all health care costs. A new study has shown that patients with POLST (Physician Orders for Life-Sustaining Treatments) forms are less likely to receive unwanted life sustaining treatments when compared to patients with traditional Do-Not-Resuscitate orders (http://www.ohsu.edu/polst/). Using the POLST did not impact the degree of comfort care received for symptom management and helped individuals make more informed choices about the type and level of end-of-life care they wish to receive.
Bottom Line: Implement sepsis protocols as soon as sepsis is suspected prior to the end of the 3 hour treatment window.
Patients may present atypically with ischemic strokes, reporting symptoms such as face or hemibody pain, lightheadedness, mental status change, headache and non-neurological symptoms.
Up to 25% of patients will have these symptoms.
Women are more likely than men to present with these atypical (or “nontraditional”) symptoms, especially altered mental status.
Background:
Animal studies in post-ROSC management after cardiac arrest have repeatedly demonstrated poorer neurological outcomes with higher amounts of oxygen administration.1 Studies in humans have also demonstrated dose-dependent associations between hyperoxia and poorer neurologic outcomes, as well as in-hospital mortality.2,3
Recent Data
A retrospective analysis of prospectively-collected data in 187 OHCA patients undergoing postarrest care with targeted temperature management found worse neurologic outcomes in patients experiencing hyperoxia in the first 6 hours following ROSC.4
This association was dose-dependent, with worsening outcomes as with higher PaO2 levels >200.
Bottom Line:
Boutonniere Deformity
aka buttonhole deformity
Misdiagnosed as a “jammed” or “sprained” finger
Recently, an ex-Russian spy and his daughter were poisoned in Salisbury, England using a Soviet nerve agent called Novichok. He joins a list of defectors and ex-spies who's poisoning have been connected to Russia.
Nerve agents are organophosphate compounds, similar to the commercially available pesticides, but significantly more potent. Nerve agents such as VX take seconds to minutes to irreversibly inhibit acetylcholinesterase by “aging” and result in clinical toxicity.
Signs and symptoms
Treatment
Worsening hypoxemia is not uncommon upon initiation of VV ECMO for severe ARDS as tidal volumes drop to double digits (often <20cc) after transition to “lung rest” ventilator settings. The following are strategies to improve peripheral oxygenation:
1. Increase the blood’s oxygen content
- Ensure FIO2 of ECMO sweep gas is 1
- Increase ECMO blood flow
o Limited by cannula size and configuration – may require placement of additional venous drainage cannula
o Also limited by greater risk of recirculation and hemolysis
- Increase blood oxygen-carrying capacity
o Transfuse PRBCs – some advocate for goal hemoglobin 12-14, though institutional practices vary significantly
2. Minimize recirculation
- Maximize distance between drainage and return cannulae
3. Reduce oxygen consumption
- Optimize sedation and neuromuscular blockade. (This is not the appropriate scenario for awake ECMO.)
- Consider therapeutic hypothermia
4. Decrease cardiac output and intrapulmonary shunt
- Consider beta blocker (esmolol) infusion
- Prone positioning (only if staff are experienced with proning on ECMO as this poses significant risk of cannula displacement)
5. Consider switching to hybrid configuration (VVA – continued venous drainage cannula and venous return cannula with addition of arterial return cannula)
Peri-Intubation Cardiac Arrest
Fluid overload (defined in this study as (fluid input-output)/weight)) is associated with longer hospital stays, longer treatment duration and oxygen use.
Bottom line: Treat dehydration appropriately but try not to over resuscitate the asthmatic. Further studies are needed before definitive recommendations are made.