So here is an awesome clip from an ICU colleague of mine, Lorraine Law. She was managing a post arrest (elderly woman who collapsed at home and was resuscitated but remaining in profound shock) case using bedside ultrasound and came across this pathology:
video courtesy of Lorraine Law & Shirish Shantidatt
what do you think?
scroll below for my thoughts…
So the clip starts with a subxiphoid 4 chamber view that clearly shows a massively dilated RV with a hyperdynamic and underfilled LV.
[For the hemodynamic novices, remember that the ventricles are kind of like roommates who share a pericardium. Especially in acute scenarios, if one gets overloaded, the other will have to give way, until the pressure equilibrates. If the process is exceedingly slow, they can do some renovations and stretch the pericardium, but this takes likely weeks. In this case, the elevated PAP overloads the RV and the RVDP > LVDP, resulting in decreased diastolic filling, which in turn drops the stroke volume/cardiac output/MAP.]
We can see that the RV TAPSE (tricuspid valve excursion towards apex) is really minimal, supporting an acute or acute on chronic process.
The clip then shows a long axis view of the IVC with echogenic material, most likely thrombus, with a to and fro motion, going in and out of the RA. Wow. You don’t see this very often. The only thing preventing further travel is actually the fact that the cardiac output is so low due to massive embolism so that the flow can in fact barely carry the clots forward anymore at this point, similar to the sluggish IVC clip I put up a few months ago (http://wp.me/p1avUV-5t).
The most likely diagnosis is pulmonary embolism, and thrombolysis is indicated. Unfortunately despite my colleague’s timely diagnosis, the clot burden was likely too much, and despite thrombolysis, the patient passed away of intractable shock. One can imagine that the TPA actually has to make it to the lungs, and with such a degree of obstruction, it is likely that very little actually got to the pulmonary vasculature…
Unfortunate case, but quite impressive images.
A crazy thought, using hindsight and with the luxury of knowing the fatal prognosis: intracardiac (RV) TPA bolus? Small spinal needle? Anyone bold enough? Food for thought if (when) I see one like this…
Really quite impressive images. A couple of weeks ago I admitted a pretty young patient after a successful resuscitation due to massive pulmonary embolism. Immediately after ROSC in emergency department, he was transported to the cath-lab where TPA bolus was administered directly through a PA cathether. In ICU we continued the infusion. In less than 24 hours we obtained a relative hemodynamic stability and discontinued all the vasopressors, but the case remains unfortunate because despite therapeutic hypothermia the post-anoxic damage was so severe that led to cerebral death declaration two days later.
Thanks Marco, very interesting. There is a recent study on catheter directed thrombolysis in PE reviewed at PulmCCM:(http://pulmccm.org/main/2014/randomized-controlled-trials/catheter-directed-thrombolysis-submassive-pe-better-heparin-rct/)
A physiological point about PE resuscitation is the relative inefficiency of CPR, as both venous return and LV filling is severely limited, so systemic perfusion is even worse than the usually poor output during chest compressions…
Thanks for reading!
The point about the possible inefficiency of CPR is crucial in my opinion. The patient I brought as example had a witnessed cardiac arrest (he called EMS when in respiratory distress) and CPR without interruption from the beginning, nevertheless he resulted in brain death declaration.
I remember very clearly a 43-year-old woman that 3 years ago had a massive PE in the OR shortly after a long lumbar vertebral stabilization. We admitted her to ICU after more than 80 minutes of CPR, a bolus of rTPA and with severe hemodynamic instability. RV was extremely dilated. When she eventually regained stability I had little hope about her neurological recovery, but surprisingly she was extubated the following day and last year she returned to our 12-months post-ICU follow-up showing perfect recovery.
I think that systemic and cerebral perfusion during “obstructive” cardiac arrests such as massive PE is very difficult to asses with current technology. A couple of times I was tempted to check it with trans cranial doppler, but usually there’s too much confusion during CPR.
When I was a resident I witnessed to a iatrogenic cardiac arrest in a patient with advanced monitoring that led to an interesting publication: http://www.researchgate.net/publication/10832333_Cerebral_perfusion_pressure_and_cerebral_tissue_oxygen_tension_in_a_patient_during_cardiopulmonary_resuscitation
Wow, very interesting cases. What fortune to have been able to record that data, as obviously getting that in during CPR would be almost impossible. TCD, at least after ROSC, could be contributory… Another option is using NIRS, which I’ll be working with this summer.