Clinical Indications for Applying (and Removing) the NASG: Rule of 20

Postpartum hemorrhage is one of the main causes of maternal mortality worldwide. Most of these occur in low-resource countries and are preventable if detected and treated in a timely manner.

Non pneumatic antishock garment (NASG) is a useful device in the management and stabilization of hypovolemic shock secondary to postpartum hemorrhage; It helps reach hemodynamic stability needed to provide comprehensive treatment, perform blood transfusions or be able to safely  refer a patient to a specialized health center.

Through its 6 neoprene segments, the NASG generates circumferential pressure, decreasing blood flow in the lower part of the body and  promoting hemorrhage control. Additionally, the applied pressure increases cardiac output and central circulation, allowing an increase in blood flow to vital organs. Direct pressure on the descending aorta reduces bleeding from the uterine arteries and mesenteric vasculature, helping stop the hemorrhage.

Studies have shown that with the use of NASG, there is a 48% decrease in maternal mortality related to hypovolemic shock secondary to postpartum hemorrhage.

It is important to take into account prophylaxis for postpartum hemorrhage with measures such as: the administration of oxytocin and active third stage of labor; as well as having a high index of suspicion of postpartum hemorrhage, especially in those patients with a high risk of postpartum hemorrhage (multiparity, previous cesarean sections, multiple pregnancy, etc.).

Indications for placing the NASG:

• Presence of signs of shock or hemodynamic instability regardless of blood loss.
• Estimated blood loss greater than 750 mL
• Shock index greater than 0.9 (defined as the heart rate divided by systolic blood pressure)
• Persistent systolic blood pressure less than 90 mmHg
• Persistent mean arterial pressure less than 65 mmHg
• Heart rate greater than 100 beats per minute

The NASG also allows simultaneous surgical procedures to be performed both vaginally and abdominally, including: bimanual uterine compression, curettage, manual vacuum aspiration, balloon tamponade, repair of uterine rupture, laparotomy, hysterectomy, hemostatic sutures, control surgery. damage etc.).

Considerations for NASG removal

The NASG must be removed in an establishment where definitive treatment is possible in case of re-bleeding (surgical capacity, availability of blood products, etc.).

The garment must be removed upon reaching hemodynamic stability for at least two hours, where it is evident:

• Blood loss less than 50 mL/hour
• Pulse less than 100 beats per minute
• Systolic blood pressure greater than 100 mmHg.
• Hemoglobin of > 7.5 mg/dL or hematocrit of 23%.

To safely guarantee its removal, you should start with the lower segments and continue upwards. Every 15 minutes a segment is released, which generates redistribution of blood flow and therefore hemodynamic variables must be assessed. If during follow-up there is a drop in systolic blood pressure greater than 20 mmHg or an increase of 20 beats per minute in heart rate, the removed segments should be repositioned and resuscitation maneuvers should be initiated immediately, as well as search for the origin of the bleeding.

The NASG is an easy-to-use device that, used correctly and in a timely manner, considerably reduces maternal mortality.

By Dr. Nestor Ferrer