Page 50 - Ultrasonography in Prehospital and Emergency Medicine - Rein Ketelaars

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Chapter 2
to a true PEA. Treatable causes were reduced ventricular function (59%), pericardial tampon- ade (9.8%), a significantly dilated right ventricle (7.8%), and hypovolemia (3.9%).66 A return of spontaneous circulation (ROSC) was indeed achieved after pericardiocentesis. Three of five tamponade patients survived to hospital admission.
Similarly, cardiac motion in PEA patients in the ED is positively associated with ROSC. Salen found that in eight of 11 (73%) patients with sonographic cardiac activity ROSC was achieved but in none of 23 without cardiac activity.67 A retrospective analysis of 318 pulseless trauma patients revealed that the survival of pulseless traumatic arrest patients without so- nographic cardiac activity is rare.68 In non-trauma ED patients, cardiac standstill on FoCUS during CPR correlated with death with a PPV of 97.1% and an NPV of 57.1%.69 However, the timing and the duration of the FoCUS examination could be very important.
Termination of resuscitation (TOR) may be considered in out-of-hospital cardiac arrest pa- tients when these four criteria are met: no ROSC before transport, no shock delivered, no bystander CPR, and an unwitnessed arrest.70 Goto developed a similar TOR rule: no pre- hospital ROSC, nonshockable initial rhythm, and unwitnessed by bystanders. Their rule is a > 99% predictor of death within one month after out-of-hospital cardiac arrest (OHCA).71 Cardiac standstill on initial FoCUS may predict non-ROSC and could be used in the deci- sion for the termination of treatment.67,72 However, a 2016 study in non-traumatic OHCA patients undergoing serial FoCUS confirmed ROSC could occur within ten minutes after initial cardiac standstill.73 However, after a cardiac standstill of ten minutes or longer no ROSC occurred. These findings suggest that PHUS might play an important role here: con- sider TOR after ten minutes of sonographic cardiac standstill?
In addition to uncovering treatable causes of cardiac arrest, FoCUS is invaluable confirm- ing mechanical ventricular capture (as opposed to electrical capture) during transcutaneous cardiac pacing.74
C – Shock
Although the cause of shock may not be apparent, FoCUS might guide therapy such as intra- venous fluid administration, inotropic therapy, and the choice of destination hospital. Fo- CUS directly altered treatment in 51% of the cardiac arrest and peri-resuscitation patients in Breitkreutz’s prehospital study.66 This implies that every hemodynamically unstable patient could potentially benefit from PHUS.