Learning Points:
1. With excellent CPR technique, patients in ventricular fibrillation can be resuscitated even after a very long down time. In this case, even with a left ventricle that could barely fill, the CPR was effective enough to have adequate perfusion. Good chest compressions, at the right rate (at least 100) and depth (at least 5 cm, or 2 inches), decompression, ITD (ResQPod), slow ventilations (10/min), are among the many critical interventions that may lead to successful resuscitation. Whether co-incidental or not in this case,
we have had good rates of conversion of VF when esmolol is given.
See this case of 68 minutes of cardiac arrest in a paramedic, plus recommendation from a 5 member expert panel on CPR.
2. Not all cardiac arrest,
even with pathologic ST elevation, is due to STEMI. Cardiomyopathies, combined with cardiac arrest, can result in bizarre ECGs. Stress cardiomyopathy may cause VF and ST elevation, and other PseudoSTEMI patterns may be present but unrelated to the VF.
3.
ECGs may be very bizarre immediately after defibrillation. Give a few minutes to record another before coming to conclusions.
4.
Bedside ultrasound is incredibly valuable in cardiac arrest, both for assessing cardiac function and for assessing carotid blood flow.
5. Pulses may be absent when there is good perfusion through the carotid. Use
Doppler carotid ultrasound to assess carotid flow. To my knowledge, there is no human literature on this.
6.
End Tidal CO2 is a good indicator of effectiveness of chest compressions.
--By this systematic review in Resuscitation 2013,
a value less than 10 mmHg (1.33 kPa) is associated with a very low return of spontaneous circulation.
--In this systematic review from J Int Care Med 2014,
the mean etCO2 in patients with return of spontaneous circulation (ROSC) was 26 mm Hg (3.5 kPa)
7. Do not do any adverse
neurologic prognostication prior to 72 hours after arrest, and it is preferable to wait even longer.
Here is one article from 2014 on this topic by Keith Lurie's group from HCMC and the U of Minnesota, and
another (on which I am a co-author) from HCMC this summer of 2014.
8. When a cardiac arrest victim has a history of "clots" and is on coumadin, one must entertain the diagnosis of pulmonary embolism. However,
ventricular fibrillation is an unusual presenting rhythm in pulmonary embolism:
--In this study, 5% of VF arrest was due to PE:
V fib is initial rhythm in PE in 3 of 60 cases.
On the other hand, if the presenting rhythm is PEA, then pulmonary embolism is likely. When there is VF in PE, it is not the initial rhythm, but occurs after prolonged PEA renders the myocardium ischemic.
--
Another study by Courtney and Kline found that, of cases of arrest that had autopsy and found that a presenting rhythm of VF/VT had an odds ratio of 0.02 for massive pulmonary embolism as the etiology, vs 41.9 for PEA.
