What defines a hypertensive emergency in a pregnant patient with eclampsia?

A hypertensive emergency in a pregnant patient with eclampsia is primarily defined by the presence of target-organ damage. In the context of eclampsia, the condition is characterized by seizures due to severe hypertension and can lead to significant complications for both the mother and fetus.

Target-organ damage can manifest in several ways, such as acute kidney injury, pulmonary edema, cerebral hemorrhage, or liver dysfunction. The presence of any of these complications indicates that the hypertension is causing real harm, which is what characterizes an emergency situation.

While a systolic blood pressure greater than 180 mm Hg and a diastolic blood pressure greater than 100 mm Hg are concerning readings, they alone do not define an emergency if there is no accompanying target-organ damage. Similarly, the goal of blood pressure reduction to less than 140 mm Hg is a therapeutic target rather than a defining characteristic of an emergency. Thus, the critical aspect that establishes hypertensive emergencies in this scenario is the evidence of target-organ damage, as it necessitates immediate and aggressive intervention to prevent further complications.