According to the heparin protocol, a patient is to receive 70 units per kilogram IV before a continuous heparin infusion is started.

For a patient weighing 60 kilograms, how many units of heparin should be administered? Whole number.

Choice A rationale

While voiding is expected, the normal range for the first void is typically within the first 24 to 48 hours of life. A newborn not voiding at exactly 24 hours warrants continued monitoring, but it is not an immediate emergency unless there are other signs of distress or an obvious obstruction.

Choice B rationale

Acrocyanosis is a normal, transient condition in the newborn characterized by a bluish discoloration of the hands and feet due to sluggish peripheral circulation. It is common for up to 24 hours after birth and does not require immediate intervention, only ongoing assessment to ensure central color is pink.

Choice C rationale

Most healthy newborns pass meconium, the first stool, within the first 24 hours of life, with almost all passing it by 48 hours. A lack of meconium passage at 24 hours requires investigation for potential intestinal issues, such as Hirschsprung's disease or meconium plug, but an elevated temperature signals more acute distress.

Choice D rationale

A temperature of 100.5 degrees F (38.1 degrees C) in a newborn, which is above the normal range (typically 97.7 to 99.5 degrees F or 36.5 to 37.5 degrees C), is a serious finding. Newborns are susceptible to rapid temperature changes, and hyperthermia can indicate sepsis, dehydration, or environmental issues requiring immediate assessment and intervention.

Choice A rationale

Testosterone is the primary male sex hormone, an androgen, responsible for the development of male secondary sex characteristics and reproductive tissues. While present in trace amounts in females, it has no direct role in the pulmonary physiology or the production of pulmonary surfactant, which is the critical deficiency leading to respiratory distress syndrome (RDS) in preterm neonates.

Choice B rationale

Somatotropin, also known as growth hormone (GH), is a peptide hormone responsible for stimulating growth, cell reproduction, and regeneration. Its main effects are on somatic growth and metabolism. Although many hormones influence fetal lung maturation indirectly, an altered secretion of somatotropin is not the primary physiological cause for the development of neonatal respiratory distress syndrome.

Choice C rationale

Surfactant is a lipoprotein complex produced by Type II alveolar cells. Its function is to lower the surface tension within the alveoli, preventing their collapse upon expiration. In preterm infants, especially those born before 34 weeks' gestation, the production of adequate amounts of surfactant is often immature or insufficient, leading to widespread atelectasis and the clinical picture of respiratory distress syndrome.

Choice D rationale

Progesterone is a major female sex hormone primarily involved in the menstrual cycle, pregnancy, and embryogenesis. It plays a crucial role in maintaining pregnancy by supporting the uterine lining. While steroid hormones are generally involved in fetal development, altered secretion of progesterone is not the main physiological factor causing the acute alveolar collapse seen in respiratory distress syndrome.