[Prospective study of prevalence hearing loss in preterm neonates in an intensive care unit]

The risk of hearing loss is higher in prematurely born infants compared with neonates born at term. It is due to unfinished development of auditory path and exposition to many harmful factors related to treatment in a neonatal intensive care unit.

Assessment of hearing loss risk factors in preterm babies.

152 newborns with mean birth weight 1408 +/- 551 g and gestational age 30.3 +/- 3.2 weeks.

After discharge follow-up (Me = 32 months) study of newborns born before 37 weeks of gestation age. The patients were assigned into two groups: A) with hearing loss (n = 9) and B) without hearing loss (n = 143) according to the results of clinical observation and audiological assessment after 6 months of life.

The rate of hearing loss was higher in new-borns born between 24-28 weeks of gestation (6/50, 12%) than in those born between 29-32 (2/52.3%) and 33-36 (1/43, 2%, p = 0.03). Identified risk factors independent of gestational age were: Gram negative sepsis (OR = 6; 95%CI: 1.32-27.33) and hyperbilirubinemia > 340 mumol/l (OR = 40.5; 95%CI: 73.27-503). The other risk factors are: shock (OR = 6.65; 95%CI: 1.44-30.64), hypercarbia (pCO2 > 80 mmHg) (OR = 5.13; 95%CI: 1.29-20.37), severe anemia (Ht < 24%) (OR = 6.0; 95%CI: 1.32-27.33). Prolonged treatment with aminoglicosides (over 10 days) also increased hearing loss risk (OR = 10.4; 95%CI: 1.27-85.75).

The risk of hearing loss is highest in the newborn born between 24-28 weeks of gestation. It can be further increased by shock, hypercapnia, severe anemia, prolonged treatment with aminoglicosides. Gestational age independent factors are: hyperbilirubinemia and Gram negative sepsis.