Sunday, December 16, 2018

Postpartum Hemorrhage - by Matt Bogard, M.D.

Postpartum Hemorrhage
Matt Bogard, M.D.
Background
          The physician who chooses to practice obstetrics engages in a physiologic process that has occurred for thousands of years prior to the advent of modern medicine.  For the Family Medicine Obstetrician, attending the deliveries of his or her patients further expands on the concept of comprehensive care.
          While laboring and vaginal delivery is often a positive experience for patients and providers alike, it is a process wrought with potential consequences that may be devastating to the mother, the fetus, or both.  The obstetrician must be vigilant and suspicious of the potential for complications to develop, and must have at his or her disposal appropriate medications, supplies, tools, and personnel for necessary intervention. 
          The recent increase in alternative birthing centers, including home deliveries, places the laboring patient in a precarious position – in the event of a complication the attendant may lack the ability to appropriately intervene.  These situations have led to recent legal challenges.1,2
          Postpartum hemorrhage is a complication of labor that requires immediate aggressive intervention to ensure maternal well-being.  Postpartum hemorrhage is classically considered to be blood loss of greater than 500mL during or following the third stage of labor, and has an incidence of nearly 18%.3  Severe postpartum hemorrhage occurs with more than 1 liter of blood loss and occurs in nearly 3% of vaginal deliveries. 

Causes
          There are many potential causes of postpartum hemorrhage.  Uterine atony is causative in approximately 70% of PPH cases.4  The second most common causative group, seen in 20% of cases, is urogenital trauma in the form of laceration, hematoma, rupture, or uterine inversion.  Retained tissue accounts for approximately 10% of postpartum hemorrhage occurrences.  A very small minority of hemorrhage is caused by coagulopathy or bleeding diathesis. 

Risk factors
There are multiple risk factors a physician must consider when contemplating the possibility of postpartum hemorrhage.  Anemia, easy bruising, clotting disorders, history of prior postpartum hemorrhage, multiple gestation, prolonged third stage of labor, episiotomy, and fetal macrosomia are all contributing factors.5  A retrospective study examining oxytoxin use during labor and the incidence of PPH found women with severe PPH secondary to uterine atony were exposed to significantly more oxytocin during labor when compared to matched controls (10,054 mU AUC compared to 3762 mU AUC in controls).6  This should prompt increased suspicion for PPH in women after a lengthy induction or augmentation.  Interestingly, regional epidural analgesia was found to be a protective factor against severe blood loss in women with postpartum hemorrhage.7

Initial resuscitation
          Acute-onset hemorrhage is a situation with which every physician should have comfort in the initial management.  Evaluation of the ABCs of life support typically centers on Circulation.  Establishment of vascular access via two large-bore peripheral IVs or one central line is necessary and should be followed with immediate fluid resuscitation comprised of isotonic fluids, either Lactated Ringer’s solution or Normal Saline.  Oxygen therapy, typically via nonrebreather mask, is initiated along with serial assessment of vital signs.  Ongoing brisk bleeding may prompt ordering of complete blood counts, coagulation profile, and type and cross donor blood products in case transfusion later becomes warranted.  In one hospital-based study, the prevalence of severe PPH was 2.36%, and the rate of transfusion of blood and blood products was 1.6%.8  In the same study, transfusion of packed red blood cells and blood component therapy was significantly more common in women after caesarean section, compared to those who delivered vaginally.  The provider must also beware that blood counts take multiple hours to stabilize after resolved hemorrhage and initial labs may not accurately portray the patient’s status.

Pneumonic Aids
          There are two helpful pneumonic aids the astute obstetrician should memorize to guide initial treatment strategies.  A recent study9 examined use of the acronym "HEMOSTASIS" in management of the patient with postpartum hemorrhage.  HEMOSTASIS includes: ask for Help; Establish etiology; Massage the uterus; Oxytocin infusion and prostaglandins; Shift to operating theater; Tamponade test; Apply compression sutures; Systematic pelvic devascularization; Interventional radiology; Subtotal/total abdominal hysterectomy.  Practitioners completing the ALSO course are taught to consider the four causative T’s of the postpartum hemorrhage:  Tone, Trauma, Tissue, Thrombin.

Vaginal Delivery Postpartum Hemorrhage
          Active Management, rather than Expectant Management, of the third stage of labor is the single best approach to prevention of postpartum hemorrhage.10 This involves administration of pitocin or other uterotonic shortly after delivery of the anterior shoulder, uterine massage prior to and after placental delivery, and controlled cord traction throughout the third stage.  When compared to Expectant Management of the third stage, in which the placenta is allowed to separate either spontaneously or aided only by gravity or nipple stimulation, the Number Needed to Treat with Active Management to prevent one case of PPH is 12.11
          Pitocin remains the primary uterotonic of choice in most cases of Active Management of the third stage of labor, in part because it may be given intravenous, intramuscular, or direct injection in the uterine vein.  Routine use of misoprostol plus pitocin resulted in modest reductions of blood loss in the third stage of labor in one study, but the effects did not reach statistical significance.12
          When postpartum hemorrhage develops following a vaginal delivery, the obstetrician should first assume uterine atony and begin immediate massage, either abdominal massage or bimanual with one hand on the abdomen and one in the vaginal vault compressing the uterus.  The labor nurse should simultaneously administer oxytocin.  The physician may reasonably elect to also administer 1mg of the Prostaglandin E1, misoprostol, rectally. 
          Additional medications available include prostaglandin F-2α, Hemabate, which may be given in patients without history of pulmonary disease, and one of two ergot alkaloids, Methergine and Ergonovine, in patients without underlying hypertension or preeclampsia. 
          As the uterus develops tone, a detailed inspection should be undertaken looking for obvious or occult trauma.  Dissolvable suture is employed to close any lacerations discovered and achieve hemostasis.  A change in vital signs out of proportion to perceived blood loss coupled with pain may represent hematoma formation.  Large or enlarging hematomas should be incised and the contained clot evacuated before applying hemostatic suture, often a figure-of-eight.13
          The third stage of labor has a mean length of 8-10 minutes and the placenta is considered retained after 30 minutes.14  Umbilical vein injection of oxytocin may accelerate the rate of placental separation.  If this fails, manual exploration with a gloved hand is typically the next step, and much easier to complete in the patient with regional anesthesia.  Finally, it may become necessary to perform curettage of the uterine cavity.15
          If the obstetrician fails to identify a cleavage plane between placenta and uterus, one must suspect invasive placenta, whether it be an accreta, increta, or percreta.  The usual treatment is hysterectomy and warrants urgent consultation with an appropriate surgeon.16
Ongoing uterine atony and hemorrhage may be treated with intrauterine balloon tamponade.  The Bakri Balloon is a 24-French catheter with a 500mL balloon that has multiple successful case reports.
In a recent study, tamponade catheters controlled postpartum hemorrhage in 18 of 20 cases (90%).17
          Finally, less than 1% of postpartum hemorrhage cases is caused by a coagulation disorder.  In these cases, treatment involves replacement of deficiencies via appropriate blood products.  Packed red blood cells, platelets, and cryoprecipitate or clotting factors may become necessary.

Operative Postpartum Hemorrhage
          The surgeon in a Cesarean Section has several additional therapies at his or her disposal.  The surgeon is always appropriate to begin with the steps outlined for vaginal deliveries; oxytocin administration, vigorous massage, prostaglandins, and ergot alkaloids.
          Uterine compression sutures running through the full thickness of both anterior and posterior uterine walls are a newer operative development for surgical management of uterine atony. Christopher B-Lynch was the first to highlight this procedure. 18 Additional similar techniques have also recently been described, such as the Hayman modification to the B-Lynch procedure.19  Both the B-Lynch and Hayman involve anchoring bilateral absorbable suture in the lower uterine segment and looping over the fundus in an anterior-posterior direction.
          A recent paper evaluated in a prospective observational study the use of a "uterine sandwich" technique (B-Lynch uterine compression sutures in association with Bakri intrauterine tamponade balloon) in women with unsuccessful medical treatment for postpartum hemorrhage.  The combined technique was successful in avoiding hysterectomy in all studied cases and was without postpartum morbidity.20
          The next operative step in controlling postpartum hemorrhage, particularly in cases with adequate uterine tone, is application of bilateral O’Leary sutures to the uterine arteries with zero or number one absorbable sutures.21
          An additional potential treatment is bilateral embolization of the uterine arteries, which appears to be an effective means by which to control postpartum hemorrhage, especially when caused by with placenta accreta.22
          In cases where all other medical or surgical methods have been employed, total or subtotal hysterectomy is the ultimate solution.

Footnotes

[1] Jose Martinez.  “Midwife Who Starred In 'Business Of Being Born' Sued By Parents Who Blame Her For Stillbirth.”  New York Daily Times.  http://articles.nydailynews.com/2009-10-22/local/17934735_1_midwife-baby-birth.
2 “Midwife Charged in Virginia With Involuntary Manslaughter.”  Fox News.  http://www.foxnews.com/us/2011/04/20/midwife-charged-virginia-involuntary-manslaughter/.
3 The Prevention and Management of Postpartum Haemorrhage.  WHO Report of Technical Working Group, 1990
4 Hossain N, Shah T, Khan N, Shah N, Khan NH.  Transfusion Of Blood And Blood Component Therapy For Postpartum Hemorrhage At A Tertiary Referral Center.  J Pak Med Assoc. 2011 Apr;61(4):343-5.
5 Advanced Life Support in Obstetrics Course Syllabus.  American Academy of Family Physicians.  2006.
6 Grotegut CA, Paglia MJ, Johnson LN, Thames B, James AH.  Oxytocin Exposure During Labor Among Women With Postpartum Hemorrhage Secondary To Uterine Atony.  Am J Obstet Gynecol. 2011 Jan;204(1):56.e1-6. Epub 2010 Nov 3.
7 Driessen M, Bouvier-Colle MH, Dupont C, Khoshnood B, Rudigoz RC, Deneux-Tharaux C.  Postpartum Hemorrhage Resulting From Uterine Atony After Vaginal Delivery: Factors Associated With Severity.  Obstet Gynecol. 2011 Jan;117(1):21-31.
8 Hossain.
9 Varatharajan L, Chandraharan E, Sutton J, Lowe V, Arulkumaran S.  Outcome Of The Management Of Massive Postpartum Hemorrhage Using The Algorithm "HEMOSTASIS".  Int J Gynaecol Obstet. 2011 May;113(2):152-4. Epub 2011 Mar 10.
10 Janice M. Anderson, M.D., and Duncan Etches, M.D., “Prevention And Management Of Postpartum Hemorrhage.”  American Family Physician. 2007 Mar 15;75(6):875-882.
11 ALSO
12 Fawole AO, Sotiloye OS, Hunyinbo KI, Umezulike AC, Okunlola MA, Adekanle DA, Osamor J, Adeyanju O, Olowookere OO, Adekunle AO, Singata M, Mangesi L, Hofmeyr GJ.  A Double-Blind, Randomized, Placebo-Controlled Trial Of Misoprostol And Routine Uterotonics For The Prevention Of Postpartum Hemorrhage.  Int J Gynaecol Obstet. 2011 Feb;112(2):107-11. Epub 2010 Dec 4.
13 Benrubi C, Neuman C, Nuss RC, Thompson RJ.  Vulvar and Vaginal Heatomas: A Retrospective Study of Conservative Versus Operative Management.  South Med Journal.  1987; 80(8):991-94
14 ALSO
15 Anderson
16 ALSO
17 Dabelea V, Schultze PM, McDuffie RS Jr.  Intrauterine Balloon Tamponade In The Management Of Postpartum Hemorrhage.  Am J Perinatol. 2007 Jun;24(6):359-64. Epub 2007 Jun 13.
18 Allam MS, B-Lynch C.  The B-Lynch And Other Uterine Compression Suture Techniques. Int J Gynaecol Obstet. 2005 Jun;89(3):236-41. Epub 2005 Apr 19.
19 Ghezzi F, Cromi A, Uccella S, Raio L, Bolis P, Surbek D. The Hayman Technique: A Simple Method To Treat Postpartum Haemorrhage.  BJOG. 2007 Mar;114(3):362-5.
20 Yoong W, Ridout A, Memtsa M, Stavroulis A, Aref-Adib M, Ramsay-Marcelle Z, Fakokunde A.
Application Of Uterine Compression Suture In Association With Intrauterine Balloon Tamponade ("Uterine Sandwich") For Postpartum Hemorrhage. Acta Obstet Gynecol Scand. 2011 Apr 18. Doi: 10.1111/J.1600-0412.2011.01153.X.
21 ALSO
22 Jung Hn, Shin Sw, Choi Sj, Cho Sk, Park Kb, Park Hs, Kang M, Choo Sw, Do Ys, Choo Iw.

Uterine Artery Embolization For Emergent Management Of Postpartum Hemorrhage Associated With Placenta Accreta.  Acta Radiol. 2011 Mar 28.
Dr. Matthew Bogard, Iowa doctor, is an emergency medicine doctor primarily at the Lucas County Health Center in Chariton, Iowa. Presently, he is Board Certified in Family Medicine by the National Board of Physicians and Surgeons and the American Academy of Family Physicians.