Outcomes in patients who received ECMO and/or volatile anesthetics as rescue therapies for status asthmaticus

Background: In the state of Kentucky many status asthmaticus (SA) patients require care in the Pediatric Intensive Care Unit (PICU) and a fraction of these patients may receive “rescue therapies” with inhaled volatile anesthetics (IVA) and/or Extracorporeal Membrane Oxygenation (ECMO). Our objective was to compare the clinical parameters of individual patients who received either or both therapies.   Methods: Children between 2-18 years of age admitted to our PICU from January 2014- July 2020 with SA were reviewed categorized as 1) patients who received IVA alone 2) patients who received IVA and then subsequently ECMO and 3) patients on ECMO alone.   Results: 1772 children with SA episodes were identified with a mortality of 13 patients.  7 children with SA were identified who received either IVA, ECMO or both. One patient received only IVA, 5 received both IVA and ECMO and one received only ECMO.  All received standard asthma therapies of steroids, albuterol, magnesium sulphate and aminophylline prior to escalation. Six out of seven refractory SA received IVA, and five (83%) of those were subsequently escalated to ECMO. pCO2 levels had no improvement after IVA administration but decreased by an average of 20 points after ECMO. Patients peak inspiratory pressures decreased within the 1 st 24 hours of ECMO cannulation from a mean of 30 to 18. There were no other complications related to ECMO placement.   Conclusion: While we cannot decisively draw any conclusions from our study due to small sample, it was noted that there was no clear advantage of using IVA prior to ECMO in our patients. Most patients who received IVA were escalated to ECMO indicating that early ECMO cannulation may be beneficial. Given the high cost and potential complications of both, there is a need for the development of well-defined guidelines for severe SA management in the PICU.