A nurse is caring for a 28-year-old postpartum client who delivered vaginally 12 hours ago after a prolonged labor of 18 hours. She is experiencing heavy vaginal bleeding with clots larger than a quarter. Her fundus is boggy and located 2 cm above the umbilicus. Vital signs are BP 90/60 mmHg, HR 110 bpm, RR 22/min. She appears pale and reports feeling dizzy when sitting up. What is the priority nursing intervention?

Immediate Priority Action: Initiate firm, one-handed fundal massage immediately. Support the lower uterine segment just above the symphysis pubis with one hand to prevent uterine inversion while using the other hand to massage the fundus in a circular motion until it becomes firm. This mechanical stimulation directly compresses the spiral arterioles at the placental site, controlling the primary source of bleeding.

Simultaneous Interventions: While one nurse performs fundal massage, call for help and activate the facility's obstetric emergency protocol. Place the client in a supine position with legs elevated to promote venous return. Administer high-flow oxygen via a non-rebreather mask at 10-15 L/min to maximize oxygen saturation despite reduced circulating volume. Ensure two large-bore IV lines are established for rapid crystalloid infusion and blood product administration as ordered.

Pharmacological Support: Anticipate and prepare for uterotonic medications as the next step in the PPH algorithm. Oxytocin (Pitocin) is typically the first-line agent, administered as an IV bolus or infusion to sustain uterine contraction. If bleeding persists, second-line agents such as methylergonovine (Methergine), carboprost tromethamine (Hemabate), or misoprostol (Cytotec) may be administered based on provider orders and contraindications.

Ongoing Assessment: Continuously monitor vital signs every 5-15 minutes, assess the firmness and location of the fundus, and quantify blood loss by weighing pads and linens (1 gram = 1 mL blood loss). Evaluate for signs of worsening shock including altered mental status, further tachycardia, and narrowing pulse pressure. Insert an indwelling urinary catheter to monitor urine output as a marker of end-organ perfusion, targeting at least 30 mL/hour.

Risk Factor Awareness: This client's prolonged 18-hour labor led to uterine muscle fatigue, a primary risk factor for atony. Other contributing factors include overdistention of the uterus from multiple gestation or polyhydramnios, use of magnesium sulfate, and retained placental fragments. If fundal massage and uterotonics fail to control bleeding, prepare for invasive interventions such as uterine tamponade with a Bakri balloon or surgical management.