Ep-PAINE-nym



Ottawa Rules

Other Known Aliasesnone

DefinitionSet of clinical decision instruments to help predict pretest probability in various injuries and need for further radiographical studies

Clinical Significance There are four Ottawa Rules clinical decision instruments that are currently used:

  • Knee
  • Foot and Ankle
  • Cervical Spine
  • Head CT in mild head injury

HistoryNamed after The Ottawa Hospital Research Institute and the University of Ottawa over series of publications from 1992-2001. These publications have been validated numerous times and shown to decrease health care costs, unnecessary radiographic studies, and decrease throughput time in the emergency department. The brain behind these studies is Ian Stiell, a Canadian physician researcher who received his medical doctorate from the University of Ontario and completed his residency at McGill University. With over 370 publications to his name, he is a powerhouse in the realm of emergency medicine research.


References

  1. Firkin BG and Whitwirth JA.  Dictionary of Medical Eponyms. 2nd ed.  New York, NY; Parthenon Publishing Group. 1996.
  2. Bartolucci S, Forbis P.  Stedman’s Medical Eponyms.  2nd ed.  Baltimore, MD; LWW.  2005.
  3. Yee AJ, Pfiffner P. (2012).  Medical Eponyms (Version 1.4.2) [Mobile Application Software].  Retrieved http://itunes.apple.com.
  4. Whonamedit – dictionary of medical eponyms. http://www.whonamedit.com
  5. Up To Date. www.uptodate.com
  6. Stiell IG, Wells GA, Vandemheen KL, et al. The Canadian C-spine rule for radiography in alert and stable trauma patients. JAMA. 2001; 286(15):1841-8. [pubmed]
  7. Stiell IG, Greenberg GH, Wells GA, et al. Derivation of a decision rule for the use of radiography in acute knee injuries. Annals of emergency medicine. 1995; 26(4):405-13. [pubmed]
  8. Stiell IG, Greenberg GH, McKnight RD, Nair RC, McDowell I, Worthington JR. A study to develop clinical decision rules for the use of radiography in acute ankle injuries. Annals of emergency medicine. 1992; 21(4):384-90. [pubmed]

PAINE #PANCE Pearl – Emergency Medicine



Question

You have a patient in the ED with an aortic dissection and are managing them while awaiting the cardiovascular surgeon to arrive.

  1. What are the two most important things to control?
  2. How do you go about doing that?


Answer

  1. The main aims of acute medical management of aortic dissections are to decrease the rate of left ventricular contraction and decrease the velocity of the contraction, which will overall decrease the shear stress at the site of the tear and slow progression.
  2. Start with intravenous beta-blockade and titrate to a heart rate of 60 betas/minute
  1. If systolic blood pressure is > 120 mmHg after successful beta-blockade, then add a vasodilator or afterload reducer.

For a deep dive into aortic dissections, check out the podcast



References

  1. Hiratzka LF, Bakris GL, Beckman JA, et al. 2010 ACCF/AHA/AATS/ACR/ASA/SCA/SCAI/SIR/STS/SVM guidelines for the diagnosis and management of patients with Thoracic Aortic Disease: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, American Association for Thoracic Surgery, American College of Radiology, American Stroke Association, Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, Society of Interventional Radiology, Society of Thoracic Surgeons, and Society for Vascular Medicine. Circulation. 2010; 121(13):e266-369. [pubmed]
  2. Tsai TT, Nienaber CA, Eagle KA. Acute aortic syndromes. Circulation. 2005; 112(24):3802-13. [pubmed]

#36 – Basics of the Ventilator with Wes Johnson, PA-C



***LISTEN TO THE PODCAST HERE***

 



Guest Information

 

Wes Johnson, MSPAS, PA-C, (soon to be), DHSc was a former student of mine at UAB and was a respiratory therapist prior to PA school.  He is the Regional Director of Clinical Education for Island Medical Management Emergency group in North Alabama.  He won the Preceptor of The Year award from UAB in 2016 and currently finishing up his doctorate degree from A.T. Still University.

Twitter – @wesj2288



Disclaimer

 

For the purposes of this podcast and post, we will be using the Puritan Bennett 840 ventilator (pictured below).  All the term we use are synonymous with all vents, but the screens will be different.

Puritan Bennett 840


Big Concepts of The Ventilator

 

  1. Mode
    1. Assist Control (AC)
      1. Every breath is either a machine driven (set by rate) or fully assisted (initiated by the patient)
        1. Uses either pressure (ACPC) or volume (ACVC)
    2. Synchronized Intermittent Mechanical Ventilation (SIMV)
      1. Set number of machine driven breaths, and patient intitated breaths are partially assisted
    3. Pressure Support (PS)
      1. No machine driven breaths and all breaths are initiated by the patient and partially assisted
  2. Delivery
    1. Pressure
      1. Static Controls
        1. Pressure
        2. Time (inspiratory)
        3. Peak flow
      2. Variable Factors
        1. Volume
        2. Total flow
    2. Volume
      1. Static Controls
        1. Tidal volume (cc)
        2. Flow (L/min)
      2. Variable Factors
        1. Pressure
  3. Positive End Expiratory Pressure (PEEP)
    1. The pressure left in the circuit at the end of expiration
    2. Prevents alveolar collapse and improves oxygenation
    3. Can cause barotrauma and affect hemodynamics

Static Controls

 

(For this section, refer back to the vent picture above)

  1. Fraction of Inspired Oxygen (FiO2)
    1. Start at 100% and titrate down to 21%
  2. f (machine breath rate)
  3. Control
    1. Pressure Control (PC)
      1. Inspiratory pressure (Pi)
        1. Peak pressure in circuit
        2. Initial setting = < 20 cm H20
      2. Inspiratory time (I-time)
        1. Initial setting = 1.25 seconds
    2. Volume Control (VC)
      1. Vt (tidal volume of each breath)
        1. Initial setting = 6-8 cc/kg IBW
      2. Vmax (flow rate)
  4. Spontaneous Support
    1. Trigger for spontaneous support
      1. Volume = V-trig
      2. Pressure = P-trig
    2. Pressure Support (PS)
      1. I was always taught at least 5 cm H20 to overcome circuit resistance

Real-Time Controls

 

  1. Flashing “C” and “S”
    1. Lets you know what breaths are controlled (machine) or spontaneous (patient)
  2. Airway Pressure
    1. Ppeak (max airway pressure)
      1. A marker of resistance
    2. Pmean (average airway pressure)
      1. A measure of alveolar pressure
    3. Pplat (small airway and alveoli pressure)
      1. A measure of compliance
  3. fTotal (machine + spontaneous breaths)
  4. I:E (inspiratory:expiratory ratio)
    1. Normal = 1:2 (at rest)
    2. Inverse ratio (2:1) can improve oxygen due to intention auto-PEEP

Wes Johnson’s Approach to Setting Up a Ventilator (after RSI)

 

Mode: AC

Vt: 6-8 mL/kg based on pt’s IBW

Rate: 12-16 bpm

FiO2: 100%

PEEP: 5.0

At the 5-minute mark:

  • Check an ABG
    • Titrate FiO2 off of PaO2 and pulse oximeter
    • Adjust minute ventilation off of PaCO2 and/or ETCO2


References

  1. Respiratory Review YouTube Channel https://www.youtube.com/channel/UCtaRF58UDVthvH36YYCttng
  2. Deranged Physiology.  Mechanical Ventilation. http://www.derangedphysiology.com/main/core-topics-intensive-care/mechanical-ventilation-0
  3. Weingart SD – “Spinning Dials – How to Dominate the Ventilator” – https://emcrit.org/wp-content/uploads/vent-handout.pdf
  4. Weingart SD. Managing Initial Mechanical Ventilation in the Emergency Department. Annals of emergency medicine. 2016; 68(5):614-617. [pubmed]
  5. Air Link Regional West – “Initial Adult Ventilator Settings” – https://www.rwhs.org/sites/default/files/airlink-factsheet-ventsettings.pdf
  6. Open Anesthesia. Modes of Mechanical Ventilation. https://www.openanesthesia.org/modes_of_mechanical_ventilation/
  7. Modern Medicine Network.  A Quick Guide to Vent Essentials. http://www.modernmedicine.com/modern-medicine/content/tags/copd/quick-guide-vent-essentials
  8. Tobin MJ. Extubation and the myth of “minimal ventilator settings”. American journal of respiratory and critical care medicine. 2012; 185(4):349-50. [pubmed]

PAINE #PANCE Pearl – Emergency Medicine



Question

 

What are the 5 main life-threatening causes of chest pain?


Answer

 

The 5 main life-threatening causes of chest pain you should ALWAYS think of are:

  1. Acute Myocardial Infarction
  2. Pulmonary Thromboembolism
  3. Pneumothorax (risk of tension)
  4. Pericarditis (risk of tamponade)
  5. Aortic Dissection

There are a few others that should also cross your mind:

  1. Esophageal Rupture (Boerhaave’s Syndrome)
  2. Acute Chest Syndrome in Sickle Cell patients
  3. Unstable angina

 


References

  1. The Five Deadly Causes of Chest Pain Other than Myocardial Infarction. JEMS. 2017
  2. Chest Pain.  Life in The Fastlane.
  3. Woods WA, Young JS, Just JS. Emergency Medicine Recall.  2000.