Sunday, May 26, 2019

Top five mistakes made by medical students during ACLS megacode exam

1. Unable to recognize ventricular fibrillation or ventricular tachycardia
There are some students who cannot differentiate VF from PEA.  This is a potentially fatal mistake because for VF, the one intervention besides CPR that is proven to increase survival to hospital discharge is defibrillation (but not for PEA).

AHA CPR Guideline 2015:
In addition to high-quality CPR, the only rhythm-specific therapy proven to increase survival to hospital discharge is defibrillation of VF/pulseless VT. Therefore, this intervention is included as an integral part of the CPR cycle when the rhythm check reveals VF/pulseless VT.

Other ACLS interventions during cardiac arrest may be associated with an increased rate of ROSC but have not yet been proven to increase survival to hospital discharge. Therefore, they are recommended as considerations and should be performed without compromising quality of CPR or timely defibrillation. In other words, vascular access, drug delivery, and advanced airway placement should not cause significant interruptions in chest compression or delay defibrillation.

There are also students who are not able to differentiate VF from polymorphic VT. This mistake is still not too bad because, according to the AHA CPR Guideline 2015:
“…if a patient has polymorphic VT, treat the rhythm as VF and deliver high-energy unsynchronized shocks (ie, defibrillation doses). If there is any doubt whether monomorphic or polymorphic VT is present in the unstable patient, do not delay shock delivery to perform detailed rhythm analysis: provide high-energy unsynchronized shocks (ie, defibrillation doses).”

2. Not putting the paddles back and resuming CPR immediately after defibrillation.

The whole purpose of providing CPR immediately after defibrillation is to minimize interruptions to CPR. DO NOT check rhythm, DO NOT check pulse. It is only AFTER the 2 minutes CPR post-defibrillation, you check RHYTHM.

AHA CPR Guidelines 2015:
After the patient is “clear,” the second provider gives a single shock as quickly as possible to minimize the interruption in chest compressions (“hands-off interval”). The first provider resumes CPR immediately after shock delivery (without a rhythm or pulse check and beginning with chest compressions) and continues for 2 minutes. After 2 minutes of CPR the sequence is repeated, beginning with a rhythm check.

3. Checking pulse immediately after defibrillation and not resuming CPR immediately

AHA CPR Guidelines 2015:

When a rhythm check by an automated external defibrillator (AED) reveals VF/VT, the AED will typically prompt to charge, “clear” the victim for shock delivery, and then deliver a shock, all of which should be performed as quickly as possible. CPR should be resumed immediately after shock delivery (without a rhythm or pulse check and beginning with chest compressions) and continue for 2 minutes before the next rhythm check.

4. Checking rhythm immediately after defibrillation and not resuming CPR immediately

This mistake is almost similar to the previous one. Both should not be checked before CPR post-defibrillation. One does not need to re-look at the cardiac monitor but rather, CPR should be resumed immediately (with a sense of urgency)

AHA CPR Guidelines 2015:
…when VF is terminated, a brief period of asystole or pulseless electrical activity (PEA) typically ensues and a perfusing rhythm is unlikely to be present

But after a 2-minute CPR, the rhythm should be checked first; and only if an organized rhythm is found, the pulse check is performed. Otherwise, for persistent shockable rhythm such as ventricular fibrillation, one does not need to check pulse. It makes no sense.

AHA CPR Guidelines 2015:
Rhythm checks should be brief, and if an organized rhythm is observed, a pulse check should be performed.

5. Checking blood pressure, explaining to patient/taking informed consent, giving sedation, etc for a patient in VF.

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