AirCare Series: Resuscitative Hysterotomy
/Introduction
For thousands of years, physicians have been instructed to perform resuscitative hysterotomy (RH, peri-mortem c-section) for many different indications ranging from religious to medical. With the advent and widespread implementation of effective cardiopulmonary resuscitation (CPR) in concert with the continuing evolution of modern obstetrics, the likelihood of the desired outcome has increased. Today, the main objective of RH is increased maternal survival through optimized medical resuscitation. In this post we will outline both the indications for the procedure as well as the technique for successfully completing a RH.
Indications
The indication for RH is maternal cardiac arrest in gestations > 20 weeks. Maternal cardiac arrest is a devastating complication of pregnancy occurring in approximately 1 in 30,000 pregnancies (1).
There are several anatomic and physiologic limitations to CPR in pregnancy:
Aortocaval occlusion (supine hypotensive syndrome) can be caused by a 20 week gravid uterus, decreasing venous return and reducing maternal cardiac output (most commonly in the supine position). Therefore, consider performing CPR in a 30 degree left lateral tilt position. This position results in increased maternal blood return via the IVC (2). Another technique is to pull/push the gravid uterus to the left side to relieve compression of the IVC.
Decreased functional residual capacity and increased oxygen demand often impede ventilatory efforts.
These considerations have been taken into account in the American Heart Association Recommendations for Cardiopulmonary Arrest in Pregnant Patients > 20 weeks (3):
Airway: the increased hormonal state of pregnancy promotes insufficiency of the gastroesophageal sphincter, increasing aspiration risk. Secure an airway early, and in the interim apply continuous cricoid pressure during positive-pressure ventilation. In addition, use an endotracheal tube 0.5 to 1 size smaller than your typical tube selection secondary to likely airway narrowing from edema (3).
Breathing: Consider reducing ventilation volumes secondary to decreased functional residual capacity.
Circulation: In general, follow the ACLS guidelines. Vasopressors do decrease blood flow to the uterus, however, there are no alternatives. The mother must be resuscitated (if you are to this point, think RH!). Remember to place patient in left lateral position as much as possible or apply leftward force to displace the uterus (decrease IVC compression).
As in all cardiac arrests, consider the cause of cardiac arrest. The differential diagnosis of cardiac arrest in the pregnant patient is broad, some of the causes more unique to pregnancy are shown below (3):
Trauma
Drug overdose
Excess magnesium sulfate. Consider empiric calcium administration.
Acute coronary syndrome. PCI is the reperfusion strategy of choice.
Pre-eclampsia/Eclampsia
Aortic Dissection (increased risk in pregnancy)
Venous Thromboembolism/PE/Stroke: pregnancy is a hypercoaguable state.
Amniotic Fluid Embolism
RH should begin within 4 minutes and completed within 5 minutes of cardiac arrest (1,4). One paper suggests that you have up to 10 minutes when in-hospital cardiac arrest (5). However, both maternal and fetal survival decrease significantly after 5 minutes (6). Therefore the time to procedure should be minimized:
Do NOT delay the procedure for the arrival of an obstetrician or neonatologist.
Do NOT evaluate for fetal cardiac activity or tocometry.
Do NOT prepare a sterile field (but be as clean as possible).
Do NOT transport to an alternative location.
Performing RH increases maternal cardiac output by 30%. There is also an undeniable inverse relationship between neuro-intact survival of fetus and cardiac arrest to delivery time by RH (6). It also likely enhances maternal resuscitation. Reports support, but "fell far from proving" that RH within 4 minutes of cardiac arrest improved maternal survival (6).
Logistics surrounding RH:
Initiate CPR immediately in accordance with ACLS. A single practitioner should be completely focused on maternal ACLS. Assign this position before proceeding. CPR should be initiated before and continued during and after RH.
Secure an airway.
Attempt left lateral tilt position or push gravid uterus to left side.
Assign a team member to complete RH.
Assign a team member to provide ongoing newborn resuscitation following delivery.
Following RH, pack the uterus and abdomen with sterile towel.
Technique
The corresponding images show the materials present in the kit we use on Air Care. There are also videos below demonstrating the technique described in the text.
Large midline vertical incision from the umbilicus to the pubic symphysis (video 1). Cut through all layers of the abdominal wall. If apparent, use linea alba as a guide (video 2).
Expose the anterior surface of the uterus. Move the bladder inferiorly. Try to avoid it, but do not waste excessive time retracting the bladder or catheterizing the patient.
Make vertical incision through the lower uterine segment of the uterus until amniotic fluid is expressed (video 3). Insert index and long fingers into the defect lifting the uterus away from the fetus. Use scissors to extend the incision to the fundus.
Deliver infant (video 4). Apply pressure to the external part of the uterus to help deliver infant.
Clamp and cut the cord. Then hand the infant off to an alternate provider for ongoing newborn resuscitation (video 5).
Deliver the placenta (video 6).
Pack the abdomen (video 7).
Give oxytocin when available.
Video 1. Midline Skin Incision
Video 2. Use Linea Alba as a Guide
Video 3. Vertical Incision Through Uterus
Video 4. Deliver Infant
Video 5. Clamp and Cut Cord
Video 7. Pack the Abdomen
