Dysrhythmia-induced sudden death, termed "sudden sniffing death syndrome," is well described phenomena due to inhalant (chlorinated and aromatic hydrocarbon) abuse. 

Common inhalants include:

Chlorinated hydrocarbons: Degreasers, spot removers, dry-cleaning agents

Fluorocarbons: Freon gas, deodarants

Toluene: Paint thinners, spray paint, airplane glue

Butane: Lighter fluid, fuel

Acetone: Nail polish remover

The common theory behind the syndrome is cardiac sensitization that increases susceptibility of the heart to systemic catecholamines (epinephrine, norepinephrine, etc).  Usually, it occurs after an episode of exertion in that any excess catecholamine exposure causes irritability of the myocardium, resulting in dysrhythmias (V. fib, V. tach) and cardiac arrest. 

If acute dysrhythmias is due to myocardial sensitization, sympathomimectis should be avoided.  Beta-adrenergic antagonist can be used for the catecholamine-sensitized heart.

Hyperthermia can be defined as a core body temperature > 38.5ºC. In contrast to fever, the body’s temperature rises uncontrollably and the body is not able to dissipate the heat. There can be many causes of hyperthermia, including from environmental exposure. 

There are two main environmental heat illnesses, heat exhaustion and heat stroke.

Heat exhaustion:

• Vague malaise, fatigue, headache
• Core temperature may be normal or elevated (below 40ºC)  
• May have tachycardia, orthostatic hypotension, clinical dehydration
• Liver function tests (transaminases) may be normal or elevated
• IMPORTANT- there is no altered mental status (i.e.: no coma or seizures)

Heat stroke

• Usually tachycardia, orthostatic hypotension, clinical dehydration
• May have hot, dry skin, but not always
• Liver function tests (transaminases) are markedly elevated
• May have rhabdomyolysis and renal failure
• IMPORTANT- Signs of altered mental status (i.e.: coma, seizure, delirium)
• Mortality may be up to 33%

Bottom line:

• Heat stroke is a life threatening emergency.
  • Early recognition and rapid appropriate therapy can save a life
• The most effective cooling is evaporative cooling along with ice packs

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Vasopressors are used in shock-states to increase mean arterial pressure (MAP) and improve distal tissue perfusion. Additionally, some agents have effects on the heart to augment cardiac output.

Receptors that vasopressors work on include: 

• Alpha-1: increase arterial tone (increases MAP) and venous tone to reduce venous pooling and augment cardiac preload 
• Beta-1: increase inotropy and chronotropy on heart muscle; also increases arterial tone
• Beta-2 and Dopamine: cause vasodilation but may actually be beneficial because this increases perfusion to cardiac, renal, and GI tissues.
• V1: arterial vasoconstriction to increase MAP
• The chart below is a summary; please note that quoted receptor effects vary depending on the source reviewed

Norepinephrine (NE): excellent vasopressor for most types of shock and recommended as a first-line agent in the Surviving Sepsis Guidelines.

• Works on alpha-1, beta-1, and beta-2 receptors. 
• Initial dosing 0.05 mcg/kg/min with a maximum dose often cited as 0.5 mcg/kg/min (though there is technically no maximum dose).

Epinephrine (a.k.a. Adrenaline): in several countries the first-line agent for shock (including sepsis).

• Works similarly to NE on alpha-1, beta-1 and beta-2; it is a more potent inotrope than NE.
• One downside is the production of lactic acid, which can sometimes lead to confusion when following serial lactates during resuscitation. 

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Question

You are scaning the liver with ultrasound and you see this. What's the diagnosis?

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Sick Sinus Syndrome

- Sick sinus syndrome (SSS) is a cardiac conduction disorder characterized by symptomatic dysfunction of the sinoatrial (SA) node.

- SSS usually manifests as sinus bradycardia, sinus arrest, or sinoatrial block, and is sometimes accompanied by supraventricular tachydysrhythmias.

- Symptoms of SSS include: syncope, dizziness, palpitations, exertional dyspnea, fatigability from chronotropic incompetence, heart failure, and angina.

- Clinically significant SSS typically requires pacemaker implantation. Approximately 30% to 50% of pacemaker implantation in the United States list SSS as the primary indication.

- 2 large, prospective cohorts with an average follow-up of 17 years, observed the incidence of SSS increases with age, does not differ between men and women, and is lower among blacks than whites.

- Risk factors for SSS included greater BMI & height, elevated NT-proBNP level & cystatin C level, longer QRS interval, lower heart rate, hypertension, and right bundle branch block.

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Some radiology pearls concerning ankle pain and fractures courtesy of David Bostick and Michael Abraham

Maisonneuve fracture – fracture of the medial malleolus with disruption of the tibiofibular syndesmosis with associated fracture of the proximal fibular shaft (http://radiopaedia.org/articles/maisonneuve-fracture)

When to look for high fibular fracture

• Isolated fracture of medial malleolus
• Isolated fracture of malleolus tertius without fracture on the lateral side
• Any painful swelling or hematoma on medial side without a fracture on x-ray

Always look for avulsion fracture of 5th metatarsal styloid in patients with ankle pain and
no obvious fractures

Dans-Weber Classification – for lateral malleolar fractures (http://radiopaedia.org/articles/ankle-fracture-classification-weber)

• Type A – fracture below ankle joint
• Type B – at level of joint with tibifibular joint intact
• Type C – fracture above joint with tears syndesmotic joint

Elevated intracranial pressure (ICP), defined as >20mmHg, is frequently encountered in patients with severe traumatic brain injury (TBI). A step-wise approach would include:

1.     Analgesia and sedation: frequently forgotten.

2.     Hyperosmolar agents: both hypertonic saline and mannitol can be used. Neither is superior.

3.     Induced arterial blood hypocarbia using hyperventilation (must monitor for cerebral ischemia)

4.     Barbiturates (last resort due to side effects)

5.     Surgical:

a.     CSF drain

b.     Decompressive craniectomy: benefits challenged by the DECRA study

Stocchetti N, Maas AIR. Traumatic Intracranial Hypertension. N Engl J Med 2014; 370:2121-30. 

Background

• Artificial nutrition is a staple of critical care
• Patients who are unable to eat, require enteral nutrition (preferred over parental nutrition)
• There are some formulas that are called "immunonutrition" which try to alter the inflammatory response seen in critical illness
• They may contain omega-3 fatty acids and essential amino acids such as arginine or glutamine, and anti-oxidants.

Data

• A recent trial (MetaPlus) was designed to see if immunonutrition could decrease the development of infections in the critically ill
• Compared to regular high protein formulas, there was no difference in mortality, duration of ventilation, or hospital length of stay

What to do

• Immuno-nutrition formulas cannot be routinely recommended
• Use regular high protein formulas
• Start within 48 hours of identifying a need

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Question

50 year-old female with diabetes complains of pain and discharge from a poorly healing wound. XRay below. What's the diagnosis?

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GRACE Score  

- The Global Registry of Acute Coronary Events (GRACE) is an international database tracking outcomes of patients presenting with acute coronary syndromes (ACS).

- GRACE score is calculated based on 8 variables: Age, HR, systolic BP, creatinine, killip class, ST-segment deviation on EKG, cardiac biomarkers, and cardiac arrest on admission.

- Several reports have shown that the GRACE score is a better predictor of clinical outcome (risk of death or the combined risk of death or myocardial infarction at 6 months) than the TIMI score.

- A recent study evaluated the relationship between GRACE score & severity of coronary artery disease (CAD) angiographically evaluated by Gensini score in patients with NSTE-MI.

- Results showed that the GRACE score has significant relation with the extent & severity of CAD as assessed by angiographic Gensini score.

- GRACE score was shown to be important both for determining the severity of the CAD and predicting death within 6 months of hospital discharge from NSTE-MI.

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Patellar tendonitis aka jumpers knee

Activity related knee pain due to degenerative, micro injury rather than an inflammatory process

Up to 20% in jumping athletes

Anterior knee pain during or after activity

Bassett Sign:
       a)  Tenderness to palpation with knee in full extension (patellar tendon relaxed)
       b) No tenderness with knee in flexion  (patellar tendon tight)
 

E-cigarette popularity has increased and with that another possible source of toxicity. The most recent MMWR shows how e-cigarette use has increased over the past 5 years. The general toxicity involves nicotine toxicity with nausea, vomiting, eye irritation as the major sources of toxicity. Only one reported death where the nicotine reservoir was accessed and then injected IV in a suicide attempt.

There are some reports of asthma exacerbations but is more likely due to the vapor flavor and not the nicotine.

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General Background:

Heat transfer is important to understand, especially when evaluating and treating someone who is hyperthermic or hypothermic. Are they really hot (or cold) from exposure, or is there an underlying metabolic or toxicological cause?

Mechanisms of Heat Transfer:

There are 4 main methods of heat transfer:

• Radiation
  • Transfer of thermal energy through space by electromagnetic waves
  • Dependent on exposed surface area
  • Normally about 60% of heat loss
• Conduction
  • Transfer of thermal energy through direct physical contact
  • Depends on conductivity of the surface (stone floors > water > air)
  • Can cause significant hypothermia for someone who is down for an extended period on a stone floor
• Evaporation
  • Transfer of thermal energy through converting liquid to a gas
  • Occurs through perspiration and respiration
  • Can lead to dehydration
• Convection
  • Transfer of thermal energy through movement of air or liquid across an object
  • Rate of heat loss depends on temperature gradient, density and velocity of moving substance
  • Can lead to extreme heat loss, especially when combined with evaporation (wet clothes on a cold, windy day)

Bottom line:

When evaluation someone for hyper- or hypothermia from a potential environmental exposure, be sure to obtain the history about where they were found and the circumstances in which they were found. This can help you develop your diagnostic differential.

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Sepsis Pearls from the Recent Literature

• Sepsis remains one of the most common critical illnesses managed by emergency physicians and intensivists.
• Recent publications and meta-analyses (i.e., ProCESS, ALBIOS, SEPSISPAM) have further refined the management of these complex patients.
• A few pearls from the recent literature:
  • Early broad-spectrum antibiotics remains the most important factor in reducing morbidity and mortality.
  • Appropriate fluid resuscitation with a balanced crystalloid solution targeting 30 ml/kg. Use a dynamic measure of volume responsiveness to determine if additional fluid needed (i.e., PLR with a minimally invasive or noninvasive cardiac output monitor)
  • Maintain adequate tissue perfusion with IVFs and vasopressors (norepinephrine) targeting a MAP > 65 mm Hg.  Patients with chronic HTN may benefit from a higher MAP goal.  If the diastolic BP is < 40 mm Hg upon presentation, start vasopressors concurrent with IVF resuscitation.

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Question

A critically-ill patient requires fluid resuscitation. Someone hands you a bag of this. What’s the pH of this fluid? 

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Nonatherosclerotic Coronary Artery Disease

- Nonatherosclerotic coronary artery disease (NACAD) is a term used to describe a category of diseases, which include: spontaneous coronary artery dissection (SCAD), coronary fibromuscular dysplasia (FMD), ectasia, vasculitis, embolism, vasospasm, or congenital anomaly.

- NACAD is an important cause of myocardial infarction (MI) in young women, but is often missed on coronary angiography.

- A small retrospective study of women <50 years of age with ACS found that 54.8% had normal arteries, 30.5% atherosclerotic heart disease (ACAD), 13% nonatherosclerotic coronary artery disease (NACAD), and 1.7% unclear etiology.

- NACAD accounted for 30% of MI’s with SCAD & Takotsubo cardiomyopathy accounting for the majority of cases. 

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Is there any benefit to the use of prednisone in the treatment of lower back pain?  One study showed that about 5% of patients receive prednisone for the treatment of their low back pain, but does it work.

A recent study by Eskin et al published in the Journal of Emergency Medicine looked at this question.  They conducted a randomized controlled trial of 18-55 year olds with moderately severe low back. Patients were randomized to receive prednisone 50mg for 5 days or placebo.

The study enrolled a total of 79 patients, and 12 were lost to follow up. At followup there was no difference in their pain, or in them resuming normal activities, returning to work, or days lost from work.  To make matters worse more patients in the prednisone group sought additional medical treatment 40% versus 18%.

Conclusion:  With the results of this study we should continue the treatment of low back pain with non-steroidials, muscle relaxants and exercise.  There does not appear to be any role for steroids in the treatment of these patients.

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6-7% of kids presenting with upper respiratory symptoms will meet the definition for ABS.

The American Academy of Pediatrics (AAP) reviewed the literature and developed clinical practice guideline regarding the diagnosis and management of ABS in children and adolescents.

The AAP defines ABS as: persistent nasal discharge or daytime cough > 10 days OR a worsening course after initial improvement OR severe symptom onset with fever > 39C and purulent nasal discharge for 3 consecutive days.

No imaging is necessary with a normal neurological exam.

Treatment includes amoxicillin with or without clauvulinic acid (based on local resistance patterns) or observation for 3 days.

Optimal duration of antibiotics has not been well studied in children but durations of 10-28 days have been reported.

If symptoms are worsening or there is no improvement, change the antibiotic.

There is not enough evidence to make a recommendation on decongestants, antihistamines or nasal irrigation.

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Since synthetic cannabinoids arrived on the scene, we have become familiar with their sympathomimetic effects such as emesis, tachycardia, hypertension, agitation, hallucinations, and seizures.

Acute kidney injury is also being linked to synthetic cannabinoid use. Several clusters have been described in a handful of states, the most recent coming from Oregon with 9 patients.

AKI seems to be one more adverse effect to be on the lookout for when evaluating patients after synthetic cannabinoid use.

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Should I Give My Patient with Septic Cardiomyopathy Fluids? 

The incidence of acute LV dysfunction in septic shock is estimated to occur in 18 - 46% of patients within the first 24 hours of shock.  Unlike the "classic" pattern of cardiogenic shock where LV filling pressure is high, in septic shock there are normal or low LV filling pressures.

Three therapeutic options should be strongly considered in the patient with a septic cardiomyopathy [CM]:

• FLUIDS:  Most patients with septic CM need fluids to restore adequate preload/afterload.  Severe vasoplegia requires volume resuscitation - even if the bedside ECHO suggests reduced contractility. Give fluids generously.
• Vasopressors: Catecholamine supplementation (norepi) improves patient's preload & afterload, but can often unmask septic CM. Consider epinephrine as a second line agent (over vasopressin) for inotropic support.
• Inotropes: Consider adding epinephrine (1 to 5 mcg/min) or dobutamine (start at 1-5 mcg/kg/min) to target an improved cardiac index (>2.5 L/min/m2) or ScVO2 > 70%.

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