emDOCs.net – Emergency Medicine EducationemDOCs Podcast - Episode 98: Post ROSC Mental Model - emDOCs.net

Today on the emDOCs cast Brit Long interviews Zachary Aust on the use of a mental model in post ROSC patients.

What’s the problem?

The Code
- Whatever caused the initial arrest
- Iatrogenic injuries from CPR
Patients are in a pathophysiologic state that is being called “post-cardiac arrest syndrome”
- Hypoxic brain injury
- Myocardial dysfunction
- Systemic ischemia/reperfusion injury
- SIRS Response
Very fragile state
Hard to diagnose what is going on
Small Things Matter

Overview – C A B S

Circulation
- Close monitoring of perfusion
- Arterial Line
- US/Doppler
- Pulse Ox
- ETCO2
- Higher MAP with Immediate Vasopressors + Fluids
- Norepinephrine or Epinephrine
Airway
- Definitive Airway (before they leave)
- Resus Before Intubation
- Use Induction+Paralytic
- Inline Waveform ETCO2
Breathing
- Keep things normal (O2/CO2)
- Be Mindful of Over-bagging
Stuff
- EKG
- POCUS-RUSH
- Temp
- Use a checklist to remember the little things

Circulation

Multi Modal Perfusion Markers
- Arterial Line
  - Femoral site preferred
  - Don’t lose focus on the resus
- Ultrasound
  - Pulsatile carotid/femoral
  - Transition to doppler after ensuring correct vessel
    - Femoral vein pulsatile during CPR
- Pulse Ox
  - Persistent waveform
    - Good indicator of mechanical HR
- End Tidal Capnography
  - Persistent elevation > 30-40
Check Heart Rate and Blood pressure
MAP Goal: 80 mm Hg
- Consider >65 if severe myocardial dysfunction but in general higher MAP
Hypotension- need to find out why but empirically treat at the same time
- Vasopressors immediately-Have at beside ready….or running during code
  - Norepinephrine is good default
  - Epi
    - Better for PE
    - Not for VTach/VFib
  - Vasopressin- especially if super acidotic
  - Dopamine-Just say no
RUSH Exam-find out why they are hypotensive
- Rule Out PTX/Tamponade
- RVD can be from code itself
- Myocardial dysfunction from etiology or post cardiac arrest syndrome
  - Serial assessments
Probably 1-2 L IVF up front, don’t blindly administer massive amounts of fluid
Bradycardia- check BP
- HTN- likely appropriate response, monitor closely can drop soon
- Hypotensive- see above
  - If you think the bradycardia is driving the hypotension sure try atropine
  - But get the epi/pacing ready

Airway

If no ETT/definitive airway they need one….not the biggest priority (focus on circulation) but sooner rather than later…before they leave the room for sure
- Remember it’s okay to use LMA during code but be using…
ETCO2 In Line Waveform
- No ETCO2 reading? Check the pulse
RSI= Resuscitation Sequence Intubation
- Hypoxia, Hypotension, and Acidosis are the reason patients code during/post intubation
- These patients are super high risk for all 4
Optimize first pass success – Induction agent + paralytic
- Unconscious patients will still have muscle tone
Induction
- Ketamine or Etomidate at half doses (i.e., Ketamine 50 mg IV)
Paralytic-double the dose
- Rocuronium is my choice
  - Unlikely to know true potassium given ischemia/reperfusion
Post Intubation analgesia/sedation
- Patients can have awareness post ROSC
- Also need to consider neuro prognostication
- Short acting agents
- Use ketamine drip if it’s an option
- Can re-dose Ketamine/Etomidate (easy to forget however)
- Propofol with a pressor less optimal here in the immediate period but once stabilized a good option
- Fentanyl
  - Pushes
  - May not be ideal for drip as it can build up but okay to start while in ED if stopping before before leaving for ICU
- Please stop using versed drips for post intubation sedation
NG/OG tube and HOB elevated

Breathing

Overview
- Target normoxia and normocapnia
- Target a SpO2 of 92-95% (PaO2 80-150)
- ETCO2 30-35 (PaCO2 35-45)
Oxygen
- Avoid both hypoxia and hyperoxia (remember the little things)
- Target a SpO2 of 92-95%
- Titrate down FiO2 to the minimum for this and as quickly as you can
- Don’t need blood gas to do this
CO2
- Avoid hypocapnia (decreased brain perfusion)
- Unclear if hypercapnia is beneficial, avoid until more date
- Verify with blood gas as needed BUT remember the ETCO2 is AT LEAST what our PaCO2 is
Use lung protective settings unless asthmatic/COPD
Over-bagging with BVM is common; will cause decrease venous return

Stuff (workup/imaging/other meds)

Targeted Temperature Management

My goal: Temp < 37.8 C
General principle of avoiding fever
Local guidelines will be the biggest influence
Evolving evidence
Continuous monitoring
Scheduled acetaminophen
Devices to cool depend on institution
Don’t over focus on this at expense of other things keep the fever down and working in conjunction with the admitting providers

Cath Lab

ROSC+STEMI= Cath Lab
- AHA/ACC Class I rec
ROSC + No STEMI= Trend EKGs
- 2014 AHA/ACC guidelines-patient with hemodynamic/electrical instability-
- Immediate invasive strategy within 2 hours- Class Ia
Dependent on patient factors + conversation with interventional cardiology
- Patient factors to consider
  - Witnessed or unwitnessed arrest, non shockable initial rhythm, bystander CPR, 30 min until ROSC, pH < 7.2, Lactate >7, age >85, ESRD, non cardiac causes likely
  - Be cautious using pH and Lactate in isolation without other factors

One thought on “emDOCs Podcast – Episode 98: Post ROSC Mental Model”

Skyler Lent says:

April 2, 2024 at 8:29 AM

This is a great mental model!

I’m not sure the MAP goal should be > 80 mmHg post arrest. This is not zero risk if having to use catecholamines to achieve a higher MAP target. The latest RCT (https://www.nejm.org/doi/full/10.1056/NEJMoa2208687) demonstrates a MAP of 63 has equivalent mortality and neurologic outcomes (even in the pre-existing hypertension subgroup) to a MAP of 77.

My goal is MAP > 65 post arrest

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