NM-238
Pulmonary Hypertension Crisis: An unexpected Challenge
Zapata A, Vener D
Texas Children's Hospital, Houston, TX, USA
Case presentation
A 2yo former 36 week infant with dTGA with IVS (s/p ASO), bronchomalacia with collapse of left mainstem bronchus and possible PAH of unknown origin presented for bronchoscopy and aortopexy vs external bronchial stent. The patient had an aborted procedure 3 months prior due to destaturation after induction to 70% without recovery requiring intubation for 3 weeks. At that time he was found to be positive for viral and bacterial infections. He was discharged on no PAH medications. No recent echos were available.
The patient was brought to the OR, standard ASA monitors + NIRS were applied and underwent an inhaled induction with sevoflurane followed by titrated doses of propofol (< 1 mg/kg) and midazolam while the airway was turned over to ENT for bronchoscopy. During bronchoscopy, the anesthesia team was placing a radial arterial line and could no longer palpate a radial pulse. NIBP showed a drop in SBP from 80mmHg to 30mmHG with minimal anesthetic. He required epinephrine x 2 doses (1mcg/kg), but returned to baseline quickly and the airway was secured. A few minutes after recovering, his blood pressure dropped again, this time requiring CPR x 8 min for hypotension, but fully recovered once again on epinephrine infusion. The patient continued to have recurring intermittent hypoxia and further surgery was aborted. He was kept in the OR for management of presumed PAH with a severely dilated RV on echo. His therapy consisted of escalating doses of epinephrine and milrinone infusions, NO administration, IV sildenafil boluses, an epoprostanol infusion (Valetri ®), and inhaled iloprost via ultrasonic nebulizer. The patient remains intubated due to severe episodes of PAH crises in the ICU.
Discussion
Though uncommon, this case illustrates the multi-modal treatment options now available in anesthetizing locations. PAH crises typically present with hypotension, hypoxia and subsequent cardiac arrest if not treated quickly. Initial therapy includes increasing FiO2, slight hyperventilation, deepening of the anesthetic, inhaled NO, and milrinone and epinephrine infusion to support the RV. Novel therapies include targeted pulmonary arterial vasodilation through the use of calcium channel blockers, and the NO, endothelin and prostacyclin pathways. We approached the crisis that occurred in our patient by using IV sildenafil (a PDE-5 inhibitor), IV epoprostenol (Valetri®) and inhaled Iloprost ® (prostacyclin analogs). The addition of these medications in the intra-operative setting may soon be playing a much larger role in our practices as we see more patients with PAH in the pediatric setting. Of note, Valetri® is ultra-short acting and requires a dedicated intravenous line with a second site available at all times while inhaled Iloprost ® requires a specialized ultrasonic nebulizer not routinely available in the OR.
References
Hansmann G (2017) Pulmonary hypertension in infants, children, and young adults. J Am Coll Cardiol 69:2551–2569
Hopper RK, Abman SH, Ivy DD. Persistent challenges in pediatric pulmonary hypertension. Chest. 2016;150:226-236.
Twite MD, Friesen RH. The anesthetic management of children with pulmonary hypertension in the cardiac catheterization laboratory. Anesthesiol Clin. 2014;32:157-173.
Top
