The answer of case 2 renal failure
1. Studies have shown that almost 100% of newborns have the first void within 24 hours after birth and nearly half of them void 8 hours after birth (Clark, 1977). Although very few infants of less than 32 weeks’ gestation were documented in these studies and the time of the first void varies considerably, failing to pass urine beyond 24 hours should prompt the physician to evaluate and intervene for newborns of any gestational age. 2. She required resuscitation at birth and has a persistently low blood pressure that may be limiting perfusion of vital organs, including the heart and kidneys. Prolonged hypotension could serve as a prerenal etiology for acute ischemic and hypoxic injury to the kidney and should be corrected immediately. A normal saline infusion at 10 mL/kg (over 30 minutes) can be given at this time, and a re- peated dose with the same volume could be considered if there is no significant improvement in the blood pressure. A renal ultrasound is also recommended