• sleep disruption silimar to a nightmare, but much more dramatic most often between 4-12 years
• sudden fear reaction which occurs during the transition to and from deep non-REM sleep while nightmares occur during REM sleep
• occurs 2-3 hours after falling asleep when the child suddenly awakens in distress and may thrash about, scream, cry
• child returns to sleep with no memory of the event the following morning
• often occurs when a child is stressed, overtired, on new medication, or sleeping in a new environment
• do not awaken the child during the event but rather allow them to calm on their own

Carbon monoxide (CO) and hydrogen cyanide (HCN) are two of the main gases causing injury and death from smoke inhalation in fire victims. During the first phase of a fire, and prior to depletion of oxygen reserves and subsequent production of CO, formation of HCN from the thermal breakdown of nitrogen-containing materials may be the primary cause of lethal poisoning in an enclosed-space fire.

A recent, retrospective, observational study from Poland assessed the prevalence of toxic HCN exposure in victims of enclosed-space fires.

Important findings:

• Of the 285 patients who died, 169 (59%) had detectable cyanide blood levels. 82% also had elevated carboxyhemoglobin (COHb) levels.
• Of the 40 patients who survived, 20 (50%) had detectable cyanide blood levels. All 20 had elevated COHb levels.

Conclusion: The high prevalence of coincident HCN concentrations and COHb levels in victims of enclosed-space fires emphasises the need to suspect HCN as a co-toxin in all persons rescued from fire who show signs and symptoms of respiratory distress.

Show References

Question

40 year-old male with severe uncontrolled hypertension presents with altered mental status (head CT below). The CXR is from the same patient. What's the connection?

Show Answer

Show References

Question

40 year-old male with severe uncontrolled hypertension presents with altered mental status. Head CT is shown here. Name three common anatomic locations generally seen for non-traumatic intracerebral hemorrhage. 

Show Answer

Show References

Which patient has a better blood pressure, the patient with a blood pressure of 110/40 or the patient with a blood pressure of 90/60?

Mean arterial pressure (MAP) is generally considered to be the organ perfusion pressure in an individual. Because MAP requires an inconvenient calculation, we've all been taught...misled perhaps...into focusing on systolic blood pressure (SBP) as a marker of how well-perfused a patient is, and we tend to ignore the diastolic blood pressure (DBP).

It's important to remember, however, that we spend most of our lives in diastole, not systole. As a result, our organs spend more time being perfused during diastole than systole. The MAP takes this into account: MAP = (SBP + DBP + DBP)/3. DBP is more important than SBP!

So which patient is perfusing his vital organs better, the one with a BP of 110/40 or the one with a BP of 90/60? Do the MAP calculation...90/60 is better than 110/40!

Pay more attention to those diastolic BPs!

Apprehension test for patellar dislocation

Test is used to access for the possibility of a patellar dislocation, prior to evaluation, now spontaneously reduced.                                                   

Similar to the shoulder apprehension test

Designed to place the patella in a position of imminent subluxation or dislocation

http://mulla.pri.ee/Kelley%27s%20Textbook%20of%20Rheumatology,%208th%20ed./HTML/f4-u1.0-B978-1-4160-3285-4..10042-7..gr16.jpg

http://www.youtube.com/watch?v=9AJxcbd9g8A

Place the knee in 20 - 30 degrees of flexion with the quadripces relaxed. Grasp the patella and attempt to place lateral directed stress.

If the patella is about to dislocate, the patient will experience apprehension due to the familiar pattern of dislocation, report the laxity and resist further motion by contracting the quadriceps

If concern arises on screening assessment, keep child in hard cervical collar and image (may start with x-ray and progress to CT if still concerned and x-rays negative).

If imaging negative, but persistent suspicion based on neurological deficits consider SCIWORA (Spinal Cord Injury WithOut Radiographic Abnormality) which exists in up to 50% of children with cervical cord injury, and may require MRI to further identify injury.

• Exposure to organophosphates can lead to “intermediate syndrome.”

• It is a syndrome characterized by weakness of neck flexors and proximal limbs, cranial nerve palsies, and respiratory muscle weakness, which can lead to respiratory paralysis.

• It follows acute cholinergic syndrome and precedes a delayed neuropathy, thus it is an “intermediate syndrome,” typically developing 24-96 hours post exposure.

• The pathophysiology of IMS remains unclear.

• Serum cholinesterase levels and electrophysiological studies are helpful in confirming the diagnosis.

• With supportive therapy, including artificial ventilation, complete recovery occurs within 5-18 days.

Right Heart Failure in the Critically Ill

• In its most simplistic form, right heart failure (RHF) is due to either to right ventricular contractile dysfunction or elevated right ventricular afterload.
  • Primary causes of RV contractile dysfunction include: coronary ischemia, sepsis, drug toxicity, and acute pulmonary hypertension
  • Primary causes of increased RV afterload include: LV dysfunction, venous thromboembolism, hypoxic pulmonary vasoconstriction, and lung injury
• Management of the patient with RHF centers on identifying and treating reversible causes, optimizing preload, inotropes, and possible implantation of a right ventricular assist device.
• Importantly, excessive volume loading can worsen RV contractile function, increase RV dilatation, and impair LV output and systemic perfusion.
• Consider early use of inotropic agents, such as dobutamine, in critically ill patients with RHF.

Show References

Question

32 year-old female presents with 5 days of fever, chills, and flank pain. She is hypotensive on presentation and urinalysis shows pyuria. Click here for the non-contrast CT scan. What's the diagnosis and what type of antibiotics should be started empirically?

Show Answer

Show References

Lyme disease is the most prevalent arthropod zoonosis in the Northern hemisphere

Show References

Carbapenems (meropenem, ertapenem, doripenem, imipenem/cilastatin) are broad-spectrum antibiotics that have good gram-negative and anaerobic coverage and are used to treat resistant bacterial infections.

• Early retrospective studies showed ~10% cross-reactivity in penicillin-allergic patients.

• More recent prospective studies verified penicillin allergy by the accepted standard (ie, skin test to the major and minor penicillin determinants) and tested for carbapenem allergy by administering a full therapeutic dose to carbapenem skin test-negative patients.

• The cross-reactivity between skin tests appears to be around 1%, with all carbapenem skin test-negative patients tolerating the challenge.

Show References

I was reading the biography of Steve Jobs looking for incredible insights into leadership and innovation. I have realized that you basically have to be a genuis and it doesn't matter what you do. His favorite drug was LSD which he believed was necessary to improve creativity and innovation. His description of the hallucinations confirm that he was taking this drug.

We describe LSD hallucinations as a crossing of the senses or "synesthesias" - you hear the color blue, you see the smell of roses.

Steve Jobs describes a moment in a wheat field while on LSD and (paraphrasing from the biography) ..." the wheat was playing Bach beautifully"

If you have a patient describing this type of hallucination you can almost be guaranteed that they have taken LSD or some other tryptamine.

A Cochrane review of 37 studies concluded that Succinylcholine (SUC) is superior to Rocuronium (ROC) during rapid sequence intubation.

The authors claim that compared to ROC, SUC has a faster onset of action (45 vs. 60 seconds) and overall a shorter duration of action (10 vs. 60 minutes).

Dr. Reuben Strayer wrote a letter to the journal editors and stated that these findings should be interpreted carefully; he highlighted that most of the studies in the review used doses of ROC less than 0.9 mg/kg (most studies used 0.6mg/kg).

Dr. Strayer asserted that ROC’s onset of action is dose dependent; when using doses of 1.2 mg/kg, ROC’s onset is indistinguishable from that of SUC. He also stated another major benefit of ROC is the lack of adverse effects that SUC possesses (hyperkalemia and malignant hyperthermia).

What are your thoughts on this? Go to http://www.facebook.com/Criticalcarenow and take the poll (there are 5 choices). Results will be posted next week.

Show References

Question

56 year-old male presents with chest pain. You perform an ultrasound of the heart and see the clip below. What's the diagnosis? Thanks to Dr. Ken Butler for the case.

Show Answer

Show References

Arrhythmogenic right ventricular dysplasia (ARVD) is a heritable form of cardiomyopathy, characterized by the replacement of myocytes with adipose and fibrous tissue leading to arrhythmias, right ventricular failure, and sudden cardiac death (SCD)

Show References

Apprehension test for shoulder dislocation

Tests for chronic shoulder dislocation                                                       

Similar to the patellar apprehension test

Designed to place the humeral head in a position of imminent subluxation or dislocation

http://www.maitrise-orthop.com/corpusmaitri/orthopaedic/112_kelly/kelly-fig11.jpg

ABduct and externally rotate arm to a position where the shoulder may dislocate

If the shoulder is about to dislocate, the patient will experience apprehension due to the familiar pattern of dislocation, report the laxity and resist further motion.

Types:
- Uniphasic anaphylaxis: occuring immediately after exposure to allergen, resolves over minutes to hours and does not recur
- Biphasic anaphylaxis: occuring after apparent resolution of symptoms typically 8 hours after the first reaction. Occur in up to 23% of adults and up to 11% of children with anaphylaxis

Treatment:
1. First line: IM epinephrine 1:1000 solution
   - vasoconstrictor effects on hypotension and peripheral vasodilation; bronchodilator effects on upper respiratory obstruction
   - NO absolute contraindication for use in anaphylaxis
   - Dosage: Adult: 0.3 - 0.5mg; Peds: 0.01mg/kg (max 0.3mg)
   - can be repeated every 5-15 minutes
2. Adjunctive therapy:
   - H1 Blocker: diphenhydramine 1-2mg/kg up to 50mg IV
   - H2 Blocker: ranitidine 1-2mg/kg
   - Corticosteroid: 1-2 mg/kg for prevention of biphasic reactions
   - Bronchodilator: Albuterol for bronchospasm
   - Glucagon: for refractory hypotension or if patient is on beta blocker
          - Dosage: Adult: 1-5 mg; Peds 20-30microgm/kg
          - Dose may be repeated or followed by infusion of 5-15 mg/min
   - place patient in recumbent position if tolerated with lower extremities elevated
   - supplemental O2
   - IV fluids for hypotension

Fatalities: typically seen with peanut or treenut ingestions from cardiopulmonary arrest. Associated with delayed or inappropriate epinephrine dosing

Disposition:
   - Mild reaction with symptom resolution: observe for 4-6 hrs (ACEP, AAP)
   - Recurrent symptoms or incomplete resolution: admit

Reference:
1. World Allergy Organization Guidelines for the Assessment and Management of Anaphylaxis, Feb 2011
2. Guidelines for the Diagnosis and Management of Food Allergy in the United States: Report of the NIAID-Sponsored Expert Panel Oct 2010

Patients that experience altered mental status (specifically lethargy) and are on valproic acid - check a serum ammonia level regardless if it is an overdose or just therapeutically on VPA.

If the ammonia is elevated in combination with the mental status change consider administration of L-carnitine either po or IV. It will lower the ammonia and improve the mental status  within hours.

High risk patients for hyperammonia who therapeutically take VPA are certain pediatric patients that experience malnutrition, have seizure disorder and are on multiple seizure medications.

Show References