Purpose: Recovery from pulmonary edema and anasarca in neonates on ECMO often requires induced diuresis. To determine whether pretreatment with theophylline (T) enhances the diuretic response to Lasix (L), we compared baseline urine volume (UV) with UV after either placebo (P) and L, or after T and L.

Methods: Twenty-four edematous infants on ECMO were randomized in a blinded, placebo controlled (independent), and a double cross-over control(dependent) design study of 72 hrs duration. Infants received either P (2.5 ml/kg D5W) or T (2 mg/kg) prior to L (1 mg/kg) IV. They were randomized to either Regimen (R)-A or R-B. R-A received P and L on day 1, T and L on day 2, and P and L on day 3. R-B received T and L on day 1, P and L on day 2, and T and L on day 3. Urine was collected via an indwelling bladder catheter for six hours prior to the start of study medication, and then for six hours after the start of medication.

Results: On day 1, baseline UV (ml/kg/hr) was not significantly different between the T+L group and the P+L group (independent control). Post-diuretic UV response showed significant increase in both groups over baseline: Table The infants who received T+L were found to have significantly higher UV than those who received P+L (*P<.05). Over 72 hrs (dependent cross-over), UV increased after T+L more than after P+L in both groups, (not tested statistically due to concerns regarding carry-over effect). Renal functions are also described during this study.

Table 1
Full size table

Conclusion: In patients on ECMO with anasarca, although UV increased significantly following L alone, priming of the kidneys with a low dose of T prior to L significantly increased UV.

Funded in part by Wyeth Pediatrics Neonatology Research Award