A 28-year-old primigravida at 32 weeks gestation presents to the emergency department with sudden onset of severe lower abdominal pain and vaginal bleeding. On examination, her uterus is markedly tender, hypertonic, and described as "wooden-hard." Fetal heart rate monitoring shows recurrent decelerations. Her blood pressure is 160/100 mmHg (baseline 130/85). The structure marked **B** in the diagram is suspected. Which of the following is the MOST appropriate immediate management for this patient?