Summary of study session V
In study session V you have learnt
- Major heamorrhage is defined as a single blood loss of > 1500 ml, continuing blood loss of 150 ml/hr or a transfusion requirement of 4 units of red cells.
- It is important to try to identify the patient at risk of major haemorrhage by understanding the known risk factors which include: grand multi-parity, increased maternal age, multiple pregnancy, women with complex medical problems, prolonged and/or obstructed labour and where there is placental abruption or fetal death.
- You should be beware of the patient who has had a previous CS and presents with a placentra praevia in her current pregnancy. These patients should only be delivered, if at all possible, where blood transfusion facilities exist.
- A team approach between obstetricians, anaesthetists, midwives and theatre staff is essential, including good communication and effective action. Without team skills, the patient may still die despite individual clinical skill and effort.
- The aim of clinical management is to rapidly restore circulating volume and prevent tissue hypoxia.
- Initial resuscitation will be the same whatever the cause of the haemorrhage. Subsequent obstetric management will depend on whether the baby is delivered and/or viable. In many cases, the patient will require an anaesthetic for exploration of the uterus and surgical haemostasis.
- The anaesthetist can initiate and lead the resuscitation and stabilization, including the estimation of blood loss and appropriate ordering of blood and blood products. The anaesthetist has responsibility to administer an appropriate anaesthetic technique to allow surgical exploration, administer drugs to control haemorrhage and help appropriate postoperative critical care.
- Any resuscitation should follow the obstetric ABC principle as follows: Tilt-if still pregnant, 100% Oxygen, ABC with rapid initial assessment and corrections as found and Diagnosis and Definitive treatment. The classic causes of antepartum obstetric haemorrhage are ruptured ectopic pregnancy, placenta praevia, placental abruption, vasa praevia, and uterine rupture.
- During the postpartum period, haemorrhage may be due to uterine atony, retained uterine products, unrecognized ongoing surgical bleeding, uterine inversion, vaginal lacerations, or placenta accreta. Early signs of impending maternal collapse with a normal blood pressure include: tachycardia, fetal distress, skin pallor with increased capillary refill time, decreased/absent urine output. Sign of life-threatening hypovolaemia i.e > 50% blood volume loss include: hypotension, tachypnoea, mental clouding progressing to unconsciousness.
- The mother will require regular heart rate and blood pressure monitoring. During active bleeding, this should be at 5-minute intervals.
- The routine administration of uterotonic drugs at delivery can dramatically reduce the risk of haemorrhage due to uterine atony. The usual first choice of drug is oxytocin or a mixture of oxytocin and ergometrine given IM or IV. Oxytocin, ergometrine, carboprost and misoprostal are all effective and any can be used in a stepwise fashion or singularly, if only one is available, once uterine atony has been diagnosed.
- If blood loss is 50% or greater than the blood volume (>2500ml) whole blood or packed red cells in an additive solution should be transfused. Aim for a Hb level of 8.0 g/dl. over-transfusion is unnecessary. O Negative blood can be used in an extreme emergency.
- The choice of anesthetic technique must be left to the individual skill and experience of the anaesthetist. However, as a general principle, if the mother does not already have a regional anaesthetic in situ, consider a GA if haemorrhage is severe, there is on-going haemodynamic instability or the diagnosis is uncertain.
- Following major obstetric haemorrhage, the mother must be care-fully monitored in an appropriate safe environment.
Última modificación: jueves, 17 de noviembre de 2016, 16:55