CC BY
38DOI: 10.5281/zenodo.1106851 UDC: 618.7-005.1
Recommended options in preventing the postpartum hemorrhage
*Capros Hristiana, MD, PhD, Assistant Professor; Mihalcean Luminita, MD, PhD, Associate Professor; Porfire Liliana, MD, PhD, Associate Professor; Surguci Mihail, MD, PhD, Associate Professor
Department of Obstetrics and Genecology, Nicolae Testemitsanu State University of Medicine and Pharmacy
Chisinau, the Republic of Moldova ^Corresponding author: [email protected]. Received July 03, 2017; accepted December 11, 2017
Abstract
Background: Postpartum hemorrhage (PPH) is a major public health problem due to complications that have a direct impact on the most important reproductive health indicators: maternal morbidity and mortality. It is a leading reason for peripartum hysterectomy, admission of pregnant women to intensive care units, and massive blood transfusion. In the most severe cases, hemorrhagic shock may lead to anterior pituitary ischemia, occult myocardial ischemia, dilutional coagulopathy. Post-partum anemia increases the risk of post-partum depression. To decrease the incidence of postpartum hemorrhage the conditions that are known to be associated with PPH and these women should be identified. Careful anamnesis and obstetrical examination should be done to screen for risk factors in pregnancy and labor. To assure minimal blood loss during delivery several measures are proposed in international protocols. The knowledge of prophylaxis measures is useful to reduce maternal mortality and morbidity from PPH.
Conclusions: The knowledge of prophylaxis measures is useful to reduce maternal mortality and morbidity from PPH. Actually, for prophylaxis of postpartum hemorrhage, evidence based medicine recommend correction of anaemia, use of the partograph in labor and the close supervision first two hours after the delivery. Key words: postpartum hemorrhage, risk factors, active management, labor.
Introduction
Postpartum hemorrhage (PPH) is the leading cause of maternal mortality in all over the world and a major cause of severe acute maternal morbidity even in well resourced settings [1, 2]. It is a leading reason for peripartum hysterectomy, admission of pregnant women to intensive care units, and massive blood transfusion. In the most severe cases, hemorrhagic shock may lead to anterior pituitary ischemia, occult myocardial ischemia, dilutional coagulopathy [3, 5]. Post-partum anemia increases the risk of post-partum depression [4]. The majority of these maternal complications can be avoided through the active management of the third stage of labor, correct diagnosis of postpartum hemorrhage and adequate treatment [5-8].
The uteroplacental circulation starts with the maternal blood flow into the intervillous space through decidual spiral arteries (fig. 1).
During placental separation, these vessels are tied off the implantation site that induces bleeding from placental site. Reduction in uterine volume after the delivery of the neonate is the result of:
- Strong third-stage contractions
- Placental delivery
- Myometrial contraction
- Compression of spiral arteries
- Clotting and obliteration of the lumen of spiral arteries
in the superficial myometrium at the placental implantation site.
This is why fatal postpartum hemorrhage can result from uterine atony. Adhered placental pieces or large blood clots that prevent effective myometrial contraction will also stimulate bleeding.
Definition. On average, women will lose about 500 ml of blood in a vaginal delivery, 1000 ml in cesarien section, and 1500 ml in a cesarean hysterectomy [9, 10, 11]. In 2012 WHO defined Primary Postpartum Haemorrhage as a blood loss of 500 ml or more within 24 hours after birth. In other guidelines and protocols primary PPH is commonly defined as excessive blood loss of 500 ml or more within 24 hours after the delivery of the baby (after the second stage of labor) in a vaginal delivery, and 1000 ml in a cesarean section [9, 10, 14, 18].
Risk factors. Unfortunately, PPH is a complication that for many women cannot be predicted. There are, however, some conditions that are known to be associated with PPH and these women should be identified. Risk factors for PPH may present antenatally or intrapartum; carefull anamnesis and obstetrical examination should be done to screen for risk factors in pregnancy and labor [11, 12]. The following risk factors for PPH are: anemia diagnosed in the beginig of pregnancy, past history of severe PPH, anticoagulant drugs in pregnancy, severe pre-eclampsia, HELLP syndrome, ute-
Fig. 1. Schematic presentation of the endometrial vascular system. The primate endometrium is composed
of the stratum basalis and stratum functionalis. Uterine arteries branch within the myometrium to yield the arcuate and radial arteries.
rine fibromas, multiple pregnancy, fetal macrosomia, obesity BMI>35, general anaesthesia, failure to progress in the second stage, prolonged third stage of labor, retained placenta, placenta accreta, episiotomy, perineal laceration [1316]. Clinicians must be aware of risk factors for PPH and should take these into account when counselling women about place and modality of the delivery. Women with significant risk factors for PPH should deliver in a unit with rapid access to blood and blood products. Women with known risk factors for PPH should only be delivered in a hospital with a blood bank on site [17, 18].
Prophylaxis. In order to minimize the risk of PPH we have to reduce blood loss during delivery.
To assure minimal blood loss during delivery several measures are proposed in international protocols:
1. Correction of anaemia.
• Screening for anaemia at the first antenatal visit and appropriate investigations should be offered to all pregnant women [19, 20]
• The aim of antenatal care is to ensure a haemoglobin level at 110 gms/dl
• In order to prevent anemia iron and folate supplementation should be offered to all pregnant women
• The most common cause of anaemia in pregnancy is iron deficiency [21, 22]
• Iron should be replaced orally or by iron infusion. Parenteral iron will be given if oral iron is not tolerated or not absorbed or the term is approaching and there is no time for oral supplementation to be effective [23-24]
• If hemoglobin level is less than 8gms/dl further investigation should be done to diagnose the cause of anemia [25]. Hemoglobin level should be checked in all women at the onset of labor. If less than 10gms/dl, they should be referred to continue labor in the referral hospital where blood is available on site [26, 27].
2. Identification of patients who refuse blood transfusion. Some women refuse the use of blood products for religious pregnant women may refuse blood transfusion because of their religious believes or infection reason. Pregnant women who refuse blood transfusion are at increased risk of severe morbidity, maternal death and perinatal com-plicatins [28, 29, 30]. In these patients all the steps should be done to minimize the risk of PPH. Antenatal care and delivery in a level 2 or 3 hospital under specialist supervision and specialist consultation at haematology department [31]:
• Optimization of iron stores with haematics
• Delivery in the facility with availability of Haemopure (a blood analogue)
• Delivery in the facility with availability of auto transfusion (cell salvage technique)
ALLEBE. Livid 28.08.19S3
RAB6-D/08 Ml 1.1 MATERNITE Tf
12.9cm /1.5 / 26Hz Tib 0.5 SFOSEI 20.02.2017
Fig. 2. Anterior placenta in the third trimester of pregnancy: hyperechoic placenta is surrounded by the hypoechoic myometrium, some calsifications and vascular lacks are seen.
• Early use of uterotonic agents, oxytocin 5 iu by slow intravenous injection for prophylaxis in the context of caesarean delivery and for women delivering vaginally, oxytocin 10 iu by intramuscular injection is the regimen of choice for prophylaxis in the third stage of labour. Intramuscular oxytocin should be administered with the birth of the anterior shoulder, or immediately after the birth of the baby and before the cord is clamped and cut.
• Early application of surgical procedures to stop the hemorrhage [32-36].
3. Determination of placental localization via ultrasound (fig. 2).
• Recognition, preparation and management of women with placenta praevia decrease the risk of catastrophic haemorrhage.
• Patients with suspected morbidly adherent placenta-tion should be detected before delivery in order to organize the delivery in the specialized units [37, 38].
4. Use of oxytocin and prostoglandins. Induction of labor should be done with precautions and with strict indications because using excessive dose of prostaglandins and oxytocin can lead to uterine rupture. Induction with pros-taglandins in the presence of uterine activity can provoke uterine. Inappropriate use of oxytocin if feto-pelvic disproportion or malpresentation are suspected can lead to uterine rupture [39, 40, 41].
5. No to the "Active management of the third stage of labour". The administration of a prophylactic uterotonic after the delivery of a baby and the controlled cord traction are recommended.The agent of choice for prophylaxis in the third stage of labour is oxytocin10 iu by intramuscular injection [42, 43, 44]. In comparison with the active management, the expectant management involves waiting for signs of placenta separation and spontaneous delivery. Compared with expectant management, the active management of the third stage of labour is associated with a substantial reduction of PPH [45,46]. Active management of the third stage includes routine early clamping of the umbilical cord. A systematic review showed that delaying clamping for at least 2 minutes is beneficial to the newborn and that the benefits extend into infancy [47, 48]. That is why active management of the third stage of labour can no longer be recommended [49].
6. Routine episiotomy. Episiotomy means incision of the perineum in order to enlarge the vaginal orifice during the second stage of labor. It can laterally be done midline or medio-lateral. There are routine episiotomy that is done for every birth and restrictive episiotomy- only under indications. Restrictive episiotomy results in less severe perineal trauma. Restrictive episiotomy results in less posterior peri-neal trauma, less suturing and fewer PPH rates [50, 51, 52].
7. Use of partogram in labour. The partograph is a graphic record of the progress of labour and relevant details of the mother and fetus. Use of partogram helps to assure
i G5
appropriate care and monitoring of women in labour because it is an early warning system to detect labour that was not progressing normally [53, 54]. The partograph has been shown to be effective in:
• Prevention of prolonged labor with the associated PPH due to the uterine atony,
• Prevention of prolonged labor with the associated PPH due to the chorioamniotis,
• Prevention of prolonged obstructed labor- the uterine rupture and associated catastrophic haemorrhage,
• Prevention of scar dehiscence and uterine rupture in case of women having labour after one caesarean section [54, 55, 56].
8. Close monitoring during first 2 hours after birth. Following delivery all women will be observed in the delivery room for 2 hours. The observation include her general physical condition, as shown by her colour, respiration and her own report of how she feels, the vaginal blood loss, blood pressure, heart rate. Early detection of PPH before blood loss has become severe and will result in earlier initiation of resuscitation and definitive treatment to arrest haemorrhage, thus reducing the morbidity from the PPH [58, 59, 60].
Diagnosis. The diagnosis of PPH is established by observing the amount of bleeding and the patient's clinical status. Physiological increase in circulating blood volume during pregnancy means that the signs of hypovolemic shock become less sensitive [61, 62].
Tachycardia, tachypnoea and a slight recordable fall in systolic blood pressure occur with blood loss of 1000-1500 ml. A systolic blood pressure below 80 mmHg, associated with worsening tachycardia, tachypnoea and altered mental state, usually indicates a PPH in excess of 1500 ml [63, 64, 65].
Blood loss estimation. We have taken into consideration that estimation of blood loss is notoriously inaccurate, especially with excessive bleeding. Also, physiological changes of pregnancy may mask the severity of blood loss. Clinical signs and symptoms should be included in the assessment of PPH. Estimation of blood loss should begin immediately after the infant's birth and prior to delivery of the placenta. Urinary catheter should be placed as soon as possible. All blood-soaked materials and clots should be taken into consideration to determine cumulative volume. 1 gram weight = 1milliliter blood loss volume [67, 69, 70].
Methods of measuring blood loss were divided into five categories:
S Visual estimation,
S Direct measurement,
S Gravimetric,
S Photometry,
S Miscellaneous methods.
For this purpose a basin in front of the external genitalia, a douche pan, underbuttocks drapes with a graduated pouch for measurement, weigh sponges and suction contents placed on a scale can be used.
Clinical signs of hemorrhage are: cool extremities, decreased urine output, dizziness, marked pallor, hypotension with sitting, anxious state, oliguria / anuria, agitation, confusion, loss of consciousness, unstable blood pressure [71,72,73].
Causes of PPH: The modern approach to the postpartum haemorrhage implies the 4T approach (tab. 1) that means implications of 4 factors in the realisation of haemo-stasis [74, 75, 76].
These 4 T of obstetric hemorrrhage are:
1. Tone (Uterine atony).
2. Trauma (Genital trauma including damage to vulva, vagina, cervix and uterus).
3. Tissue (Retained and invasive placenta).
4. Thrombin (Coagulopathy).
Table 1
"4 T" causes of post-partum hemorrhage
Tissue. Placental causes: Tone. Uterine atony.
Retained placenta Hyperstimulation
Retained clots High parity
Placenta previa Obstructed labor
Placenta accreta/increta/ Early preterm labor
percreta Uterine overdistention
Hydatiform mole Large fetus- estimated fetal weight
> 4kg
Multiple fetuses
Hydramnios
Labor induction
Anesthesia or analgesia
Halogenated agents
Conduction analgesia with hypo-
tension
Labor abnormalities
Rapid labor
Prolonged labor
Augmented labor
Previous uterine atony
Chorioamnionitis
Sepsis syndrome
Trauma. Injuries to the birth Thrombin. Coagulopathy
canal Congenital coagulopathies
Episiotomy and lacerations Placental abruption
Forceps or vacuum delivery Sepsis syndrome
Cesarean delivery or hyste- Severe preeclampsia
rectomy Syndrome
Uterine rupture Acute fatty liver
Previously scarred uterus Anticoagulant treatment
Intrauterine manipulation Amnionic-fluid embolism
Midforceps rotation Prolonged retention of dead fetus
Breech extraction Massive transfusions
Shoulder dystocia
If the placenta is out, the most common cause is uterine atony, diagnosed by palpation of a poorly contracted uterus. This is first done by knowing if the placenta has been delivered or not. If retained then the management follows along the retained placenta route in the algorithm. Perineal tears will be diagnosed on routine inspection after vaginal delive-
i (S6
ry. If there is no response to oxytocin infusion additional oxytocic agents should be given as indicated in the algorithm. First line is represented by ergometrine and misoprostol, but intramyometrial PGF2alpha requires a special indications to administer. However at this stage, in the presence of persisting bleeding, it is very important to exclude another cause such as deep vaginal lacerations, cervical tears and/or retained fragments of placenta or membranes.
Conclusions
The knowledge of prophylaxis measures is useful to reduce maternal mortality and morbidity from PPH. Actually, for prophylaxis of postpartum hemorrhage, evidence based medicine recommend correction of anaemia, use of of the partograph in labor and the close supervision first two hours after the delivery.
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