UMEM Educational Pearls - By Bryan Hayes

Category: Toxicology

Title: Ketamine for Prehospital Agitation - Prospective Study Results

Keywords: ketamine, agitation, prehospital, haloperidol (PubMed Search)

Posted: 6/7/2016 by Bryan Hayes, PharmD (Emailed: 6/9/2016) (Updated: 6/27/2016)
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Ketamine is gaining traction as a prehospital option for managing severe agitation or excited delirium syndrome. Previous reports have mostly been case series, but a new prospective study adds some important information that may help delineate ketamine's role in this setting. [1] The study and an accompanying commentary are both open access. [2]

What They Did

Open-label before-and-after prospective comparison of haloperidol (10 mg IM) versus ketamine (5 mg/kg IM) for the treatment of acute undifferentiated agitation.

What They Found

  • Ketamine demonstrated a statistically and clinically significant difference in median time to sedation compared to haloperidol, 5 min vs. 17 min (p < 0.0001, 95% CI: 9 15)
  • Complications: ketamine, 49%; haloperidol, 5%
    • Ketamine complications: hypersalivation (38%), emergence reaction (10%), vomiting (9%), and laryngospasm (5%)
  • Intubation rate: ketamine, 39%; haloperidol, 4%

Appliation to Clinical Practice

  • Ketamine works for prehospital agitation (and more rapidly)
  • Ketamine has a higher complication and intubation rate
  • Though this study did not find a dose relationship between ketamine and intubations, future studies should evaluate further and potentially use lower ketamine doses
  • At our institution, we start with 2-3 mg/kg IM and repeat if necessary after 5 min. Most patients have not required a second dose and none have been intubated. This allows time to place an IV line and initiate additional treatment.

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Category: Pharmacology & Therapeutics

Title: Clindamycin vs. Bactrim for Uncomplicated Wound Infection

Keywords: clindamycin, trimethoprim-sulfamethoxazole, wound infection, TMP-SMX (PubMed Search)

Posted: 6/2/2016 by Bryan Hayes, PharmD (Emailed: 6/4/2016) (Updated: 6/4/2016)
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In settings where community-acquired MRSA is prevalent, which antibiotic is best for uncomplicated wound infections?

New Study

  • A new multicenter, randomized, double-blind trial in 500 patients compared 7 days of clindamycin 300 mg 4 times daily to trimethoprim-sulfamethoxazole (TMP-SMX) 4 single strength tablets twice daily.
  • Follow-up was performed on days 3 4 (on therapy), 8 10 (end of therapy), 14 21 (test of cure), and 49 63 (extended-follow-up).

What They Found

  • Clinical cure rate was > 90% in both groups in the per-protocol population (p = 0.91), and also similar in the intention to treat populations.
  • Cultured bacteria were similar between the two groups:
    • MRSA ~40%
    • MSSA ~25%
    • Coagulase-negative staph ~15%
    • Strep species ~5%

Application to Clinical Practice

  1. It seems like either clindamycin or TMP-SMX are appropriate antimicrobial choices in uncomplicated wound infections.
  2. In this study, strep species were a minor component of the total cases. TMP-SMX is generally not strong against strep species, while clindamycin has good coverage.
  3. Consult your local antibiogram when appropriate. At our institution, clindamycin has poor in vitro susceptibility against MRSA.

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Category: Toxicology

Title: Does Digoxin Immune Fab Work in Chronic Digoxin Poisoning?

Keywords: digoxin, chronic, poisoning, immune Fab (PubMed Search)

Posted: 5/9/2016 by Bryan Hayes, PharmD (Emailed: 5/12/2016) (Updated: 5/12/2016)
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Patients with chronic digoxin toxicity generally have multiple co-morbidities such as renal failure, dehydration, and cardiac failure. Sick patients with chronically high digoxin levels may have more than just digoxin toxicity as the cause of illness.

A New Study

Prospective observational study with the primary objective to investigate changes in free digoxin concentrations and clinical effects on heart rate and potassium concentrations in chronic digoxin poisoning when digoxin immune Fab are given.

What They Found

One to two vials of digoxin immune Fab initially bound all free digoxin confirming Fab efficacy. However, this was associated with only a moderate improvement in HR (49 to 57 bpm) and potassium (5.3 to 5.0 mmol/L).

Application to Clinical Practice

  • Elevated digoxin concentrations alone may not be solely responsible for bradycardia and hyperkalemia in the chronic setting.
  • Digoxin immune Fab is not a magic bullet in chronic digoxin poisoning.

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Category: Pharmacology & Therapeutics

Title: Predicting Hemodynamic Response to Ketamine for Prehospital RSI

Keywords: ketamine, shock index, hemodynamic, prehospital, RSI (PubMed Search)

Posted: 5/3/2016 by Bryan Hayes, PharmD (Emailed: 5/7/2016) (Updated: 5/7/2016)
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Ketamine is often thought to be the induction agent least associated with hypotension in the peri-intubation period. However, reports of hypotension following ketamine do exist, including 2 cases of cardiac arrest. [1] There are limited objective means to predict which patients may have an adverse hemodynamic response.

New Study

A new prospective observational study followed 112 patients in the prehospital setting who received ketamine for rapid sequence intubation. 81 had a low shock index [< 0.9], 31 had a high shock index. [2]

Shock index = HR / SBP

What They Found

Patients with a high shock index were more likely to experience hypotension (SBP < 90 mm Hg) in the peri-intubation period compared to those with a low shock index (26% vs 2%).

Application to Clinical Practice

  • This is the first study to evaluate a potential objective predictor for which patients may experience hypotension after RSI with ketamine. But, even with a high shock index, the majority of patients did not develop hypotension.
  • These findings should not lead to avoidance of ketamine in these situations, as other induction agents are equally or more likely to cause adverse hemodynamic effects.
  • It has been suggested to use lower induction doses in patients at risk for hypotension (with the same or higher paralytic dose). Patients with a high pre-RSI shock index may be the population in which to consider that approach.

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Category: Toxicology

Title: ECMO for Severely Poisoned Patients

Keywords: Extracorporeal Membrane Oxygenation, ECMO, toxicology, poison (PubMed Search)

Posted: 4/13/2016 by Bryan Hayes, PharmD (Emailed: 4/14/2016) (Updated: 4/14/2016)
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The American College of Medical Toxicology's ToxIC Registry is a self-reporting database completed by medical toxicologists across 69 insitutions in the US.

  • Over a 3 year period, just 10 cases in the database received ECMO: 4 pediatric, 2 adolescent, and 4 adults (individual cases presented in the table below)
  • Time of initiation of ECMO ranged from 4 h to 4 days, with duration from 15 h to 12 days
  • Exposures included carbon monoxide/smoke inhalation (2), bitter almonds, methanol, and several medications including antihistamines (2), antipsychotic/antidepressant (2), cardiovascular drugs (2), analgesics (2), sedative/hypnotics (2), and antidiabetics (2)
  • Overall survival rate was 80%

Application to Clinical Practice

In settings where ECMO is available, it may be a potential treatment option in severely poisoned patients. From the limited data, ECMO was generally administered prior to cardiovascular failure and might be of benefit particularly during the time the drug is being metabolized.

Table from the Case Series

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Category: Pharmacology & Therapeutics

Title: Vancomycin Loading Doses in ED Not Associated with Increased Nephrotoxicity

Keywords: vancomycin, loading dose, nephrotoxicity (PubMed Search)

Posted: 3/24/2016 by Bryan Hayes, PharmD (Emailed: 4/2/2016) (Updated: 4/2/2016)
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Guidelines recommend loading doses of vancomycin (15-20 mg/kg, up to 30 mg/kg in critically ill patients), but the risk of nephrotoxicity is unknown. A new retrospective cohort study aimed to compare nephrotoxicity in ED sepsis patients who received vancomycin at high doses (>20 mg/kg) versus lower doses (20 mg/kg).

What They Found

  • 1,330 patients had three SCr values assessed for the primary outcome

  • High-dose initial vancomycin was actually associated with a lower rate of nephrotoxicity (5.8% vs 11.1%)

  • After adjusting for age, gender, and initial SCr, the risk of high dose vancomycin compared to low dose was decreased for the development of nephrotoxicity (RR=0.60; 95% CI: 0.44, 0.82)

Application to Clinical Practice

It appears initial loading doses of vancomcyin > 20 mg/kg do not cause increased risk of nephrotoxicity.

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Category: Toxicology

Title: Treatment of Acute Cocaine Cardiovascular Toxicity

Keywords: cocaine, toxicity, cardiovascular (PubMed Search)

Posted: 3/9/2016 by Bryan Hayes, PharmD (Emailed: 3/10/2016) (Updated: 3/12/2016)
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Acute cocaine toxicity can manifest with several cardiovascular issues such as tachycardia, dysrhythmia, hypertension, and coronary vasospasm. A new systematic review collated all of the available evidence for potential treatment options. Here is what the review found (there is also an 'other agents' section for medications with less published reports):

  • Benzodiazepines and other GABA-active agents: Benzodiazepines may not always effectively mitigate tachycardia, hypertension, and vasospasm from cocaine toxicity.

  • Calcium channel blockers: Calcium channel blockers may decrease hypertension and coronary vasospasm, but not necessarily tachycardia.

  • Nitric oxide-mediated vasodilators: Nitroglycerin may lead to severe hypotension and reflex tachycardia.

  • Alpha-adrenoceptor blocking drugs: Alpha-1 blockers may improve hypertension and vasospasm, but not tachycardia, although evidence is limited.

  • Alpha-2-adrenoceptor agonists: There were two high-quality studies and one case report detailing the successful use of dexmedetomidine.

  • Beta-blockers and alpha/beta-blockers: No adverse events were reported for use of combined alpha/beta-blockers such as labetalol and carvedilol, which were effective in attenuating both hypertension and tachycardia.

  • Antipsychotics: Antipsychotics may improve agitation and psychosis, but with inconsistent reduction in tachycardia and hypertension and risk of extrapyramidal adverse effects.

  • Sodium bicarbonate: Twelve case reports documented treatment of dysrhythmia with IV sodium bicarbonate, with seven reporting successful termination.

The authors note that "publication bias is a concern, and it is possible that successful treatment and/or adverse events have not been reported in some of the publications, and in general."

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A new guideline for convulsive status epilepticus in adults AND children was recently published. [1] An insightful commentary was published alongside it (both are open access). [2] The proposed algorithm is below. Here are a few additional points to note:

  • The guideline applies to convulsive status epilepticus.
  • A new level of evidence rating of "U" is utilized. It means "data inadequate or insufficient; give current knowledge, treatment is unproven."
  • It addresses 5 specific questions:
    • Which anticonvulsants are efficacious as initial and subsequent therapy?
    • What adverse events are associated with anticonvulsant therapy?
    • Which is the most effective benzodiazepine?
    • Is IV fosphenytoin more effective than IV phenytoin?
    • When does anticonvulsant efficacy drop significantly?
  • IM midazolam is incorporated as one of the recommended 1st choices of treatment.
  • One of the second phase therapy recommendations is levetiracetam 60 mg/kg! It is a level U recommendation. Be prepared for neurology to request this dose. There is no data in adults to support this high of a dose.

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Category: Toxicology

Title: Lipid use in poisoning: comprehensive systematic reviews now published

Keywords: lipid, intralipid, poisoning, local anesthetic, non-local anesthetic (PubMed Search)

Posted: 2/10/2016 by Bryan Hayes, PharmD (Emailed: 2/11/2016) (Updated: 4/2/2016)
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In September 2013, an international group representing major societies in toxicology and nutrition support began collaborating on a comprehensive review of lipid use in poisoning. Six total papers will be published, with the most recent two made available online this week. Here are the available (and forthcoming) papers:

  1. Gosselin S, et al. Methodology for AACT evidence-based recommendations on the use of intravenous lipid emulsion therapy in poisoning. Clin Toxicol 2015;53(6):557-64. [PMID 26059735]

  2. Grunbaum AM, et al. Review of the effect of intravenous lipid emulsion on laboratory analyses. Clin Toxicol 2016:54(2):92-102. [PMID 26623668]

  3. Levine M, et al. Systematic review of the effect of intravenous lipid emulsion therapy for non-local anesthetics toxicity. Clin Toxicol. 2016;54(3):194-221. [PMID 26852931]

  4. Hoegberg LC, et al. Systematic review of the effect of intravenous lipid emulsion therapy for local anesthetic toxicity. Clin Toxicol. 2016;54(3):167-93. [PMID 26853119]

  5. Hayes BD, et al. Systematic Review of Clinical Adverse Events Reported After Acute Intravenous Lipid Emulsion Administration. Clin Toxicol. 2016 Apr 1. [Epub ahead of print] [PMID 27035513]

  6. The final paper, which is in process, is the consensus recommendations from the workgroup based on the 4 systematic reviews.

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Category: Pharmacology & Therapeutics

Title: Does Succinylcholine Increase Mortality in Severe TBI Patients?

Keywords: succinylcholine, rocuronium, mortality, traumatic brain injury, RSI (PubMed Search)

Posted: 2/4/2016 by Bryan Hayes, PharmD (Emailed: 2/6/2016) (Updated: 2/6/2016)
Click here to contact Bryan Hayes, PharmD

An interesting new study was published looking at in-hospital mortality in TBI patients who received succinylcholine or rocuronium for RSI in the ED.

What They Did

  • Retrospective cohort study
  • 233 patients (149 received succinylcholine, 84 received rocuronium)
  • Groups were well matched overall (roc group was older, more hypotension in sux group)
  • Within the two groups, patients were separated based on head Abbreviated Injury Score (scores of 4 or 5 were considered severe)
  • The authors controlled for a lot of confounding factors

What They Found

  • Overall, mortality was the same in each group (23%)
    • Mortality within the roc group was the same irrespective of head AIS
    • Mortality within the sux group was significantly higher in the subset of patients with higher head AIS (OR 4.1, 95% CI 1.18-14.12, p = 0.026)

Application to Clinical Practice

  • Succonylcholine may increase mortality in severe TBI patients undergoing RSI in the ED compared to rocuronium
  • The confidence interval was wide and these findings need to be confirmed in a prospective study
  • Though the patients were well matched and the authors controlled for many variables, it still is difficult to pinpoint one intervention as the cause for mortality in critically ill patients (eg, etomidate + sepsis)
  • With proper rocuronium dosing, intubating conditions are similar to succinylcholine. So if there is a potential for increased mortality in severe TBI patients with sux, rocuronium seems to provide a safer alternative.

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Category: Toxicology

Title: A Simpler IV Acetylcysteine Regimen for Acetaminophen Overdose?

Keywords: acetaminophen, acetylcysteine (PubMed Search)

Posted: 1/7/2016 by Bryan Hayes, PharmD (Emailed: 1/14/2016) (Updated: 1/14/2016)
Click here to contact Bryan Hayes, PharmD

The three-bag IV acetylcysteine regimen for acetaminophen overdose is complicated and can result in medication/administration errors. [1] Two recent studies have attempted simplifying the regimen using a two-bag approach and evaluated its effect on adverse effects. [2, 3]

Study 1 [2]

Prospective comparison of cases using a 20 h, two-bag regimen (200 mg/kg over 4 h followed by 100 mg/kg over 16 h) to an historical cohort treated with the 21 h three-bag IV regimen (150 mg/kg over 1 h, 50 mg/kg over 4 h and 100 mg/kg over 16 h).

The two-bag 20 h acetylcysteine regimen was well tolerated and resulted in significantly fewer and milder non-allergic anaphylactic reactions than the standard three-bag regimen.

Study 2 [3]

Prospective observational study of a modified 2-phase acetylcysteine protocol. The first infusion was 200 mg/kg over 4-9 h. The second infusion was 100 mg/kg over 16 h. Pre-defined outcomes were frequency of adverse reactions (systemic hypersensitivity reactions or gastrointestinal); proportion with ALT > 1000 U/L or abnormal ALT.

The 2-phase acetylcysteine infusion protocol resulted in fewer reactions in patients with toxic paracetamol concentrations.

Final word: Two-bag regimens seem to offer advantages compared to the traditional three-bag regimen with regard to reduced adverse drug reactions. Look for more data, particularly on effectiveness, and a potential transition to a two-bag approach in the future.

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Category: Pharmacology & Therapeutics

Title: Sugammadex for Reversal of Non-Depolarizing Neuromuscular Blockers

Keywords: sugammadex, rocuronium, NMBA, vecuronium (PubMed Search)

Posted: 12/29/2015 by Bryan Hayes, PharmD (Emailed: 1/2/2016) (Updated: 1/2/2016)
Click here to contact Bryan Hayes, PharmD

After three failed attempts, the FDA finally granted approval for Merck's non-depolarizing neuromuscular blocker reversal agent sugammadex (Bridion). Though the product has been used in Europe and Asia for several years, hypersensitivity concerns led to the delayed approval in the U.S.

Important points

  1. Reverses rocuronium, vecuronium, and to a lesser degree, pancuronium
  2. Full reversal obtained about 3 minutes after administration
  3. Eliminated entirely by the kidneys in about 8 hours (6 times longer in patients with CrCl < 30 mL/min)
  4. Dosing is generally 2-4 mg/kg. Total body weight should be used in obese patients

Application to Clinical Practice

  1. Potential for use in situations where a neuro exam is needed shortly after intubation (eg, status epilepticus, ICH)
  2. The risk of serious hypersensitivity appears to be < 1% in published literature
  3. Cost will most assuredly be high
  4. Long duration in patients with reduced kidney function means further attempts to re-paralyze with roc, vec, or pancuronium may be unsuccessful

The EM PharmD blog discusses sugammadex's approval in more detail.

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Category: Toxicology

Title: Lipid Emulsion's Effect on Labs

Keywords: laboratory, lipid, toxicology (PubMed Search)

Posted: 12/10/2015 by Bryan Hayes, PharmD
Click here to contact Bryan Hayes, PharmD

The American Academy of Clinical Toxicology's Lipid Emulsion workgroup has published its first of 4 systematic reviews on the use of lipid emulsion in toxicology, this one on lipid's effect on laboratory analyses. [1] As expected, administering a fat bolus can significantly alter labs drawn subsequently.

The key point: If you are considering lipid for overdose, draw labs prior to giving it.

Which labs are affected? Most. Here's a helpful mnemonic courtesy of Dr. Kyle DeWitt.

  • B - Blood Gas
  • L - Liver transaminases
  • E - Electrolytes
  • A - Analgesics (acetaminophen, salicylates)
  • C - Coags
  • H - H/H, platelets

Also remember to give lipid in its own line. It isn't compatable with most resuscitation drugs. [2]

Show References



Category: Pharmacology & Therapeutics

Title: Therapeutic Tramadol Use Significantly Increases Seizure Risk

Keywords: tramadol, seizure (PubMed Search)

Posted: 12/3/2015 by Bryan Hayes, PharmD (Emailed: 12/5/2015) (Updated: 7/6/2016)
Click here to contact Bryan Hayes, PharmD

Tramadol has a reputation for being a safe, non-opioid alternative to opioids. Nothing could be further from the truth. Several blogs have published about the dangers of tramadol:

But what about seizure risk? Previous studies have been unable to confirm an increased seizure risk with therapeutic doses of tramadol (Seizure Risk Associated with Tramadol Use from EM PharmD blog). However, a new study refutes that premise.

22% of first-seizure patients had recent tramadol use!

  1. Mean total tramadol dose in last 24 hours (reported): 140 mg
  2. Duration of tramadol use less than 10 days: 84.5%
  3. Seizure within 6 hours of tramadol consumption: 74%

This was a retrospecitve study without laboratory confirmation of tramadol intake. Nevertheless, it behooves us not to think of tramadol as a safer alternative to opioids. It is an opioid after all, and it comes with significant adverse effects.

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Category: Toxicology

Title: Andexanet Alfa for the Reversal of Factor Xa Inhibitor Activity

Keywords: Andexanet, apixaban, rivaroxaban, factor Xa (PubMed Search)

Posted: 11/12/2015 by Bryan Hayes, PharmD
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Not to be outdone by the recent FDA approval of Idarucizumab to reverse dabigatran, a new factor Xa reversal agent is under investigation. "Andexanet binds and sequesters factor Xa inhibitors within the vascular space, thereby restoring the activity of endogenous factor Xa and reducing levels of anticoagulant activity, as assessed by measurement of thrombin generation and anti factor Xa activity, the latter of which is a direct measure of the anticoagulant activity."

Design

Two parallel randomized, placebo-controlled trials (ANNEXA-A [apixaban] and ANNEXA-R [rivaroxaban]) were conducted in healthy vounteers to evaluate the ability of andexanet to reverse anticoagulation, as measured by the percent change in anti factor Xa activity after administration.

What they Found

Compared to placebo, andexanet significantly reduced anti-factor Xa activity, increased thrombin generation, and decreased unbound drug concentration in both the apixaban and rivaroxaban groups.

Application to Clinical Practice

  1. This drug is not yet FDA approved.
  2. These trials were funded by the maker of andexanet (Portola Pharmaceuticals) and supported by the makers of apixaban and rivaroxaban.
  3. Studies are needed in patients requiring urgent reversal.
  4. The trials looked only at laboratory markers of anticoagulation. We don't know how fast (or the extent of) the reversal activity is in the clinical setting.

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Category: Pharmacology & Therapeutics

Title: Avoid Opioids for Low Back Pain

Keywords: low back pain, opioids, naproxen, oxycodone, cyclobenzaprine (PubMed Search)

Posted: 10/21/2015 by Bryan Hayes, PharmD (Emailed: 11/7/2015) (Updated: 11/7/2015)
Click here to contact Bryan Hayes, PharmD

If there weren't enough reasons to avoid opioids, here is another: opioids don't work for low back pain (LBP).

Objective

A well-done, double-blind, randomized controlled trial from JAMA set out to compare functional outcomes and pain at 1 week and 3 months after an ED visit for acute LBP among patients randomized to a 10-day course of (1) naproxen + placebo; (2) naproxen + cyclobenzaprine; or (3) naproxen + oxycodone/acetaminophen.

Intervention

  • Nontraumatic, nonradicular LBP of 2 weeks’ duration or less
  • All patients were given 20 tablets of naproxen, 500 mg, to be taken twice a day.
    • They were randomized to receive either 60 tablets of placebo; cyclobenzaprine, 5 mg; or oxycodone, 5 mg/acetaminophen, 325 mg. Participants were instructed to take 1 or 2 of these tablets every 8 hours, as needed for LBP.
  • Patients received a standardized 10-minute LBP educational session prior to discharge.

Outcome

Neither oxycodone/acetaminophen nor cyclobenzaprine improved pain or functional outcomes at 1 week compared to placebo, and more adverse effects were noted.

Application to Clinical Practice

Among patients with acute, nontraumatic, nonradicular LBP presenting to the ED, avoid adding opioids or cyclobenzaprine to the standard NSAID therapy.

Show References



Category: Toxicology

Title: Dabigatran and Hemodialysis: Watch for the Rebound

Keywords: hemodialysis, dabigatran, rebound (PubMed Search)

Posted: 10/7/2015 by Bryan Hayes, PharmD (Emailed: 10/8/2015) (Updated: 10/8/2015)
Click here to contact Bryan Hayes, PharmD

In patients receiving renal replacement therapy as a treatment modality for dabigatran-related bleeding, watch for a rebound concentration increase after hemodialysis is stopped.

More than 50% of patients demonstrate a rebound effect with a median increase in dabigatran concentration of 33%.

OOIt is unclear whether this rebound effect is clinically
important, and whether this translates to prolonged clini-

It is unclear whether this rebound effect is clinically important, and whether it translates to prolonged clinically relevant bleeding. Extended hemodialysis sessions or consideration of CVVHD should offset this potential problem.

 

Bonus Pearl:

The North American Congress of Clinical Toxicology starts today and runs through October 12. Look for toxicology pearls and updates on Twitter under the official conference hashtag #NACCT15.

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Category: Pharmacology & Therapeutics

Title: Targeted Temperature Management's Effect on Drugs

Keywords: targeted temperature management, drug (PubMed Search)

Posted: 9/27/2015 by Bryan Hayes, PharmD (Emailed: 10/3/2015) (Updated: 10/3/2015)
Click here to contact Bryan Hayes, PharmD

An excellent new review article provides a detailed look at how the drugs we give are affected by targeted temperature management. Here is a helpful chart of drug alterations that have data in reduced body temperature states:

Other Important Points:

  1. Lingering effects of sedatives may confound prognostication and may even mimic brain death. Concentrations of remifentanil, propofol, and midazolam decrease during rewarming, whereas no change has been demonstrated for fentanyl, indicating that the pharmacokinetic alterations fentanyl incurs during induction and maintenance of hypothermia persist during and following the rewarming phase.
  2. Continuous infusions of analgesics, sedatives, and hemodynamic support agents may require closer monitoring and smaller incremental changes compared to normothermic states.
  3. The QTc interval is increased in TTM, though it has not been associated with an increased risk of torsades de pointes or in-hospital mortality.

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Category: Toxicology

Title: Eye Drops and Effect on Pupil Size

Keywords: eye drops, pupil size, ophthalmic (PubMed Search)

Posted: 9/8/2015 by Bryan Hayes, PharmD (Emailed: 9/10/2015) (Updated: 9/11/2015)
Click here to contact Bryan Hayes, PharmD

In the evaluation of ED patients, it may be important to understand the effect on pupil size from the ophthalmic medications they use. Here is a summary chart of common eye drops and their effect on pupil size.

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Category: Pharmacology & Therapeutics

Title: Ketamine vs. Morphine for Analgesia in the ED

Keywords: ketamine, analgesia, morphine, pain (PubMed Search)

Posted: 8/30/2015 by Bryan Hayes, PharmD (Emailed: 9/5/2015) (Updated: 9/5/2015)
Click here to contact Bryan Hayes, PharmD

A new prospective, randomized, double-blind trial compared subdissociative ketamine to morphine for acute pain in the ED.

What they did

  • 45 patients received IV ketamine 0.3 mg/kg (mean baseline pain score 8.6)
  • 45 patients received IV morphine 0.1 mg/kg (mean baseline pain score 8.5)
  • Source of pain was abdominal for ~70% in each group
  • Exclusion criteria was pretty standard

What they found

  • Pain score at 30 minutes: 4.1 for ketamine vs. 3.9 for morphine (p = 0.97)
  • No difference in the incidence of rescue fentanyl analgesia at 30 or 60 minutes
  • No serious adverse events occurred in either group
  • Patients in the ketamine group reported increased minor adverse effects at 15 minutes post-drug administration
Application to clinical practice
  1. In an effort to reduce opioid use in the ED, low-dose ketamine may be a reasonable alternative to opioids for acute analgesia.
  2. State nursing regulations govern who can administer IV ketamine in the ED.
  3. What to prescribe on discharge? Lead author Dr. Motov recommends a "pain syndrome targeted" approach with "patient-specific opioid and non-opioid analgesics."

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