A client at 10 weeks gestation has just been admitted to the antepartum unit with severe vomiting and dehydration. The client is diagnosed with hyperemesis gravidarum. Which of the following orders is the priority nursing action to be performed?

Hyperemesis gravidarum is characterized by severe, persistent nausea and vomiting in pregnancy that leads to dehydration, electrolyte imbalances, and weight loss. The priority intervention for a client who is already dehydrated is establishing intravenous access to administer IV fluids, because correcting the fluid and electrolyte deficit is the most urgent physiological need. Without adequate hydration, the client risks worsening electrolyte disturbances, hemodynamic instability, and harm to both mother and fetus. Placing the client on a clear liquid diet is inappropriate as an immediate first step because the client is actively vomiting and cannot tolerate oral intake; oral feeding would be reintroduced gradually only after symptoms are controlled. Administering a PO prenatal vitamin is also contraindicated at this point, as oral medications would likely be vomited and could worsen nausea. Obtaining a urine sample is an important assessment — urine specific gravity and ketone levels help gauge the degree of dehydration — but it is a diagnostic step, not a treatment. While urine collection is valuable, it does not correct the underlying fluid deficit. Using Maslow's hierarchy and the ABCs framework, restoration of fluid volume to maintain circulation takes precedence over assessment and dietary measures in a dehydrated, actively vomiting client.