1430 tolazoline: limited efficacy in pulmonary vaso-reactive hypoxemia

ABSTRACT The persistent fetal circulation syndrome is associated with significant mortality, despite the availability of pharmacologic agents that dilate pulmonary vasculature. Presently,

the most commonly used agent is tolazoline (TLZ). Our 5 yr experience with TLZ includes 39 neonates treated for refractory hypoxemia, defined as PaO2 <50 torr in an FiO2=1.0 with

mechanical ventilatory support. Infants received 1-2 mg/kg by bolus, followed by 2-6 mg/kg/hr continuous infusion. A positive response was a sustained increase in PaO2 >20 torr lasting

120 min: 41% of patients responded. The mean increase of PaO2 in responders was 96.3 torr ±17 SEM (p<0.01) vs the non-responders' mean increase of 5.9 torr ±1.8 SEM (p<0.01).

Tachyphylaxis occurred in 6 patients (15%). These infants required a gradual increase in dose to 5-6 mg/kg/hr to sustain a response. At this dose no further response was seen; 50% of

patients with tachyphylaxis died. Review of other complications revealed: 41% had increased gastric secretions; 28.2% became hypotensive; 23% had gastric bleeding; 12.8% developed

thrombocytopenia (<100,000); 7.7% developed tachycardia (>180/min); 5% had decreased urine output (<1 cc/kg/hr); 2.6% had pulmonary hemorrhage. Conclusions: 1) <50% of patients

responded and response appeared to ba an all or none phenomenon, 2) response is associated with improved survival, and 3) despite initial response, TLZ tachyphylaxis occurred in some infants

with an associated decrease in survival. ARTICLE PDF AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Dept. of Pediatr., Coll. of Med., U. of Kentucky, Lexington Melinda R Slack, Nirmala S

Desai, M Douglas Cunningham & Jacqueline A Noonan Authors * Melinda R Slack View author publications You can also search for this author inPubMed Google Scholar * Nirmala S Desai View

author publications You can also search for this author inPubMed Google Scholar * M Douglas Cunningham View author publications You can also search for this author inPubMed Google Scholar *

Jacqueline A Noonan View author publications You can also search for this author inPubMed Google Scholar RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE

Slack, M., Desai, N., Cunningham, M. _et al._ 1430 TOLAZOLINE: LIMITED EFFICACY IN PULMONARY VASO-REACTIVE HYPOXEMIA. _Pediatr Res_ 15 (Suppl 4), 681 (1981).

https://doi.org/10.1203/00006450-198104001-01459 Download citation * Issue Date: 01 April 1981 * DOI: https://doi.org/10.1203/00006450-198104001-01459 SHARE THIS ARTICLE Anyone you share the

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