Intratracheal furosemide in infants after cardiac surgery: its effects on lung mechanics and urinary output, and its levels in plasma and tracheal aspirate.
OBJECTIVE
Recent studies have suggested direct pulmonary effects of furosemide in asthmatics and infants with bronchopulmonary dysplasia. We tested the hypothesis that intratracheally administered furosemide also increases respiratory compliance in children after cardiac surgery, and investigated whether furosemide has a topical and/or systemic action.


METHODS
Prospective study with intra-individual control. In twelve infants and toddlers (age: 10 +/- 8 months, weight: 6.9 +/- 3 kg) mechanically ventilated for compromised lung mechanics after cardiac surgery, 0.5 mg/kg furosemide was intratracheally administered to the lungs. Lung mechanics were serially assessed using a computerised system (Sensormedics 2600) during a 2 h control and 2 h intervention period. Urine output was measured by an indwelling bladder catheter and levels of furosemide were determined in blood and tracheal aspirates.


RESULTS
Static compliance improved within 30 min in all patients, reached a maximum of 44 (20-85)% above baseline and remained improved throughout the study (p < 0.05). An immediate, short and significant diuretic effect of intratracheally applied furosemide was observed. Furosemide levels 1 h after intervention were 795 ng/ml in the blood and 431 micrograms/ml (i.e. 1000-fold higher) in the tracheal aspirate. Changes in compliance were correlated only to urine output values over the 2 h (r = 0.82, p = 0.044, n = 9) after furosemide administration.


CONCLUSIONS
We conclude that intratracheally applied furosemide improves static compliance in infants and toddlers with compromised lung mechanics after cardiac surgery. We demonstrated that furosemide is absorbed from the lung and has a systemic effect within 15 min after its intratracheal instillation.
Aufricht
C
C
Universitäts-Kinderklinik, University of Vienna, Austria.
Votava
F
F
Marx
M
M
Frenzel
K
K
Simbruner
G
G
D000287:Administration, Topical; D004232:Diuretics / Q000494:pharmacology* / Q000627:therapeutic use; D005260:Female; D005665:Furosemide / Q000494:pharmacology* / Q000627:therapeutic use; D006330:Heart Defects, Congenital / Q000601:surgery*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008170:Lung Compliance / Q000187:drug effects; D008297:Male; D010949:Plasma / Q000737:chemistry; D011182:Postoperative Care; D011446:Prospective Studies; D012121:Respiration, Artificial; D015656:Respiratory Mechanics / Q000187:drug effects*; D018709:Statistics, Nonparametric; D014132:Trachea / Q000502:physiology; D014554:Urination / Q000187:drug effects
D004232:Diuretics; D005665:Furosemide