You are performing a repeat cesarean delivery on a 37-year-old G3P2 woman with placenta previa. Immediately after delivery, a postpartum hemorrhage occurs. You order additional uterotonic medications and blood products and prepare for standard surgical interventions including uterine devascularization, uterine compression sutures, and intrauterine balloon tamponade. As the hemorrhage continues, you begin to consider the need to perform a hysterectomy.
Suddenly the anesthesiologist reports that the patient’s blood pressure and heart rate have decreased. She asks you to initiate aortic compression to slow the pelvic bleeding and permit initiation of interventions to restore intravascular volume and optimize cardiovascular status. You have not previously performed this maneuver, and you wonder how to respond to her request.
Preoperative preparation
Anticipating possible adverse outcomes is a key task for every clinician. In the above case, in the setting of a repeat cesarean delivery in a woman with placenta previa, there is an increased risk of postpartum hemorrhage. Therefore, appropriate blood products and equipment should be made available before the operation is initiated. It also may be helpful to review the sequential steps you have found most useful in managing a postpartum hemorrhage prior to starting the procedure.
Rapid response to obstetric hemorrhage
When postpartum hemorrhage occurs during a cesarean delivery, there are many interventions that may successfully control the excessive blood loss, including uterotonics, massive transfusion of blood products, uterine massage, tranexamic acid, uterine devascularization, uterine compression sutures, intrauterine balloon tamponade, uterine artery embolization, uterine tourniquet, internal iliac artery ligation, hysterectomy, and pelvic packing.1 Rapid response to obstetric hemorrhage is important to avoid depletion of coagulation factors and subsequent development of a coagulation disorder. Once a coagulation disorder occurs, it can be very difficult to resolve the problem and complete the surgery.
Abdominal compression
The potentially benefial role of abdominal compression to help reduce blood loss caused by trauma or obstetric hemorrhage has been studied extensively in healthy volunteers. The theory is that abdominal compression will decrease blood flow in the distal aorta, helping to control bleeding in the pelvis and extremities. In one report, 80 to 140 lb of pressure applied to the epigastrium in 9 healthy male participants in a supine position on a rigid surface resulted in decreased blood flow in the common femoral artery as determined by pulsed-wave Doppler ultrasound.2 Abdominal pressure applied above the umbilicus also has been reported to reduce blood pressure in the legs.3 Abdominal compression and tourniquets used on the extremities are not meant to be definitive treatments for traumatic hemorrhages but rather are used to stabilize severely injured patients during transport to emergency surgical care facilities.4
One approach to performing manual abdominal aortic compression involves first gaining a mechanical advantage by positioning yourself above the epigastric area with arms extended. Using one closed fist with the opposite hand providing additional pressure, the equivalent of 80 to 140 lb can be applied to the patient’s upper abdomen.4 To estimate the pressure you can achieve using this method, cover a scale with a towel and use your arms to exert maximum pressure on the scale. What equivalent weight can you reach when applying maximum pressure? What weight can you sustain for a few minutes? Using manual compression, it is difficult for a clinician to exert the equivalent of 140 lb on the epigastrium for the extended period of time needed to transport an injured person to an emergency facility.5 Therefore, mechanical devices such as the abdominal aortic tourniquet (AAT) and the nonpneumatic antishock garment (NASG) have been developed to aid in providing continuous abdominal compression.
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