Which way does air flow when alveolar pressure is greater than atmospheric pressure?
a. into the lungs, called expiration
b. out of the lungs, called inspiration
c. into the lungs, called inspiration
d. out of the lungs, called expiration

Ahealthy 26-year-old woman sustained a significant crush injury to her right upper extremity while on the job at a local construction site. she was brought to the emergency department and subsequently underwent pinning and reconstructive surgery and received perioperative broad-spectrum antibiotics. her blood pressure remained normal throughout her hospital course. on the second hospital day, a medical consultant noted a marked increase in her creatinine, from 0.8 to 1.9 mg/dl. her urine output dropped to 20 ml/h. serum creatine kinase was ordered and reported as 3400 units/l. questions what are the primary causes of this patient’s acute kidney injury? how should her kidney injury be categorized (as prerenal, intrarenal, or postrenal)? how should she be treated?