Deficiency of surfactant is seen in -

Ans. is 'c' i.e., HMDEtiopathogenesis of HMD o Surfactant deficiency (decreased production and secretion) is the primary cause of RDS.o Normally surfactant helps to reduce surface tension in the alveoli ---> In the absence of surfactant, surface tension increases and alveoli collapse during expiration.Why HMD is more common in preterm baby ?o With advancing gestational age increasing amounts of surfactant is produced.o Mature levels of pulmonary surfactant are usually present after 35 weeks.o So, chance of HMD is inversely related to gestational age -f more the gestational age (more mature the neonate), less the chance of HMD.Also knowo Surfactant stas appearing in fetal lung by 20th week of gestation.o It appears in amniotic fluid between 28-32 weeks of gestation.