UMEM Educational Pearls - By Haney Mallemat

  • Many clinicians use end-tidal CO2 to monitor respirations during procedural sedation or mechanical ventilation
  • Typically either the presence (or absence) of a "normal" waveform or the quantitative value is used, however a lot more information can be gathered from the actual shape of the waveform; below are a few examples.
  • For more examples of interpreting waveforms, click HERE.

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  • Amiodarone and lidocaine are commonly used antiarrhythmics for ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT). Their efficacy towards survival to hospital discharge and neurological outcome, however, has been questioned.
  • A recently published study in the NEJM evaluated these drugs by performing a double-blind, randomized, placebo-control trial. The trial evaluated patients presenting with out of hospital cardiac arrest secondary to VF or pulseless VT that is refractory to one or more shock.
  • The trial randomized 3,026 patients to receive amiodarone (974), lidocaine (993), or normal saline (i.e., placebo) (1,059); the primary outcome was survival to hospital discharge and the secondary outcome was favorable neurological outcome at hospital discharge. Several sub-group analyses were planned a priori.
  • No statistically significant difference was found in hospital survival or neurologic outcomes between any of the groups. Patients who had a witnessed arrest and bystander CPR had higher rates of survival with either lidocaine or amiodarone compared to saline while there was no difference between the two.

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  • The RUSH exam is a rapid way to identify the cause of shock using ultrasound. What's the RUSH exam? Click here
  • The RUSH exam does not include an assessment of volume responsiveness (VR), but a new article by Blaivas, Aguiar, and Blanco suggests that it should be.
  • VR has classically been assessed by determining the stroke volume before and after a passive leg raise or a fluid bolus. Click here for a video on how to calculate the stroke volume (skip to 21:30 in the video)
  • The authors claim that VR can further be simplified by not measuring the left ventricular outflow tract (LVOT) and only comparing changes in the velocity-time integral (VTI). The assumption is that the LVOT is constant and doesn't change in most circumstances; a change of VTI that is greater than 15% suggests that the patient is VR
  • Further validation is required to determine the degree of benefit to adding VTI to the RUSH exam, however measuring VTI is a skill that can be done with relatively little training and is clinically helpful.

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Question

19 year-old male complaining of left arm pain one week after injecting anabolic steroids into his shoulder. What's the diagnosis?

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  • Transthoracic echocardiography (TTE) is an essential tool during cardiac arrest because it identifies potentially reversible causes (e.g., tamponade, massive PE, etc.).
  • One of the limitations of TTE is that it is sometimes difficult to assess the heart in less than ten seconds (i.e., during a pulse check) and good views of the heart sometimes hard to obtain. Transesophageal echocardiography (TEE) offers the potential to overcome these obstacles.
  • TEE not only allows continuous visualization and better imaging of the heart during arrest, but it also allows the assessment of compression depth, and whether the heart is being correctly compressed during CPR.
  • Here is what a TEE probe looks like, here is an example of a TEE during arrest, and here is a podcast by @ultrasoundpodcast on the literature for using TEE during cardiac arrest.

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Question

23 year-old female presents complaining of progressive right lower quadrant pain after doing "vigorous" exercise. CT abdomen/pelvis below. What’s the diagnosis? (Hint: it’s not appendicitis)

 

 

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There are so many variables to monitor during CPR; speed and depth of compressions, rhythm analysis, etc. But how much attention do you give to the ventilations administered?

The right ventricle (RV) fills secondary to the negative pressure created during spontaneously breathing. However, during CPR we administer positive pressure ventilation (PPV), which increase intra-thoracic pressure thus reducing venous return to the RV, decreasing cardiac output, and coronary filling. PPV also increases intracranial pressure by reducing venous return from the brain.

So our goal for ventilations during cardiac arrest should be to minimize the intra-thoracic pressure (ITP); we can do this by remembering to ventilate "low (tidal volumes) and slow (respiratory rates)"

  • Low: Use only one-hand while bagging, this will give the patient 500-600cc per breath. Using two-hands provides ~900-1,000cc per squeeze (more than we normally ventilate patients who have a pulse).
  • Slow: Ventilate patients at 8-10 breaths per minute. The less you ventilate the less time the patient spends with positive ITP. Observational studies have demonstrated that providers ventilate too fast during code so the use of a metronome or timing light provides critical feedback.

 

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Question

What’s the name of this CT finding and name two potential causes?

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Question

79 year-old male with headaches, ataxia, falls, and difficulty urinating. What's the diagnosis?

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Question

A patient arrives in acute respiratory distress with left sided chest pain. Ultrasound of the left anterior chest is shown; what's the diagnosis and name one false positive?

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Question

A patient presents with the sudden of onset chest and abdominal pain which woke her up at 2am. She has abdominal tenderness and rebound on exam, what's the diagnosis?

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Question

27 year-old presents after being punched in the face. Decreased vision in left eye, what's the diagnosis?

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Question

Patient presents with right elbow pain after a fall. What's the diagnosis and what other injury should you look for?

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Question

An elderly patient presents with a history of weight loss and chronic constipation. The abdominal Xray is shown below. What's the diagnosis?

This one is tricky so here's a hint: why is the right kidney and psoas muscle so well defined?

 

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Question

Patient complains of facial and neck swelling, what's the diagnosis?

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There is more than the standard preparations of plasma, platelets, and PRBCs in the blood bank. Certain patients will require these specialized preparations when a transfusion is required. Here are three to know:

  • Leukoreduced (PRBCs are run through a filter to reduce the total WBC burden)
    • Most of the blood in USA is leukoreduced
    • Should be requested for pre-transplant patients and patients who previously experienced febrile non-hemolytic reactions
  • Irradiated PRBCs (radiation incapacitates donor WBCs)
    • Irradiation prevents the fatal transfusion-associated graft versus host disease, which occurs in patients who are severely immunosuppressed or who are closely related to the blood product donors.
  • Washed RBCs/platelets (washing removes plasma, cell fragments and excess potassium)
    • Washed cells are used for neonates/pediatric patients due to sensitivity to potassium in normal products; in adults, it is used for patients with prior allergic reactions to blood products or IgA deficiency

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Question

8 year-old female presents with nausea, vomiting, double-vision and inability to move her left eye upwards after being kicked in the face at school. What's the diagnosis?

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Question

5 year-old boy who presents with sudden onset hoarse voice, and drooling without a fever. 

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Question

Patient presents after being started on an antibiotic for cellutlitis of lower extremity. What's the diagnosis and what are some other etiologic agents (name 3)

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Question

26 year-old male presents with a swollen 4th digit and pain during extension, what’s the diagnosis?

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