obstetric haemorrhage Flashcards
(30 cards)
what is MBRACE?
its an audit
mothers and babies reducing risk through audits and confidential enquiries across the age
how common is death from obstetric haemorrhage?
remains a major cause of death in developing countries
not common in UK - still occurs though
what is PPH atony?
post party haemorrhage as uterus is completely relaxed - needs to contract to stop blood flow.
what is secondary post part haemorrhage?
defined as abnormal or excessive bleeding from the birth canna between 24 hours and 12 weeks after birth.
what happens to blood volume during pregnancy?
large increase in blood volume from 70ml/kg to 100ml/kg
- eg 70kg lady at booking = blood volume increase from 4900 to 7000ml
plasma volume increases 40-50%
red cell mass increases 20-30% produces relative anaemia.
how does clotting change in pregnancy?
pregnancy is a relatively hypercoagulable state, but during pregnancy neither clotting or bleeding times are abnormal
there is a decrease in fibrinolytic activity - these changes tend to prevent excessive bleeding at delivery
fibrinogen is markedly increased
clotting factors increase -
clotting factors increased = II, VII, VIII, X, XI, XII
platelets - the number rises within the normal range
DDimer levels are elevated in pregnancy
what changes in physiology during haemorrhage?
changes in HR an BP
- HR increases
- heart beats more forcefully
- the blood vessels become constricted (increased systemic vascular resistance)
- the body secretes less urine so the body loses less fluid.
only when you have lost 30% of your blood volume does you BP start to drop
woman may have lost a lot of blood before they become really unwell
during obstetric haemorrhage why is it hard to estimate blood loss?
its really hard to estimate blood loss accurately due to amniotic fluid mixed
you could look at the pre delivery Haemoglobin and then after/during haemorrhage to see if estimated blood loss is correct.
haemorrhage shock classification
Class 1 - up to 15% blood loss, normal heart rate BP RR and urine output, they may be slightly anxious. To replace fluid they are given crystalloid.
class 2 - 15-30% blood loss, mildly tachycardic, normal/slightly decreased BP, mildly tachypnea, urine out put = 0.5-1 ml/kg/hour, mildly anxious, give crystalloid.
class 3 - 30-40% blood loss moderate tachycardia, decreased blood pressure, moderate tachypnea, 0.25-0.5 ml/kg/hour, anxious and may be confused, give crystalloid and blood
class 4 ->40%, severe tachycardia, decreased BP, severe tachypnea, negligible urine output, they will be confused/lethargic. replace fluid loss with crystalloid and blood
what are the 4 causes of obstetric haemorrhage?
- tone - abnormalities of uterine contraction (contraction will shut of all blood vessels and prevent bleeding)
- Tissue - retain products of conception
- Trauma - of the genital tract
- Thrombin - abnormalities of coagulation
Tone - cause for obstetric haemorrhage
risk factors
risk factors for atonic bleeding
- prolonged labour
- over-distended uterus - twins, triplets, large baby, poly-hydramnios.
tissue - cause for obstetric haemorrhage
risk factors
main cause is retained placenta
may be because its stuck or takes a while to detach.
sometimes you get retained products of conception - means the uterus is not empty so can not contract properly .
Placenta Praevia - placenta is in the way - under the heads so baby can’t be delivered .
morbidly adherent placenta - when there has been previous scaring to the uterus which can lead to abnormal placentatio - acreta, increta, percreta.
trauma - cause for obstetric haemorrhage
risk factors
uterine trauma - inverted uterus (uterus passes through cervix), ruptured uterus (old c section scars), surgical damage e.g. broad ligament tears at c section.
genital tract trauma - vaginal tears - first through to 4th degree tears.
thrombin - cause for obstetric haemorrhage
risk factors
acquired coagulopathy in pregnancy
- sepsis: PROM (premature rupture of membranes), endometritis(infection of the endometrium), chorio-amnionitis.
- pre eclampsia/ eclampsia
- placental abruption
- HELLP syndrome
- retained dead fetus
- amniotic fluid embolus
- DIC
- liver disease: AFLP, pregnancy can cause fatty liver disease - so clotting factors not produced as well
Platelet abnormalities
- gestational thrombocytopenia
- idiopathic/immunological thrombocytopenia
idiopathic/immunological thrombocytopenic purpura
- HELLP syndrome
- sepsis
- DIC
thrombin - cause for obstetric haemorrhage
risk factors
acquired coagulopathy in pregnancy
- sepsis: PROM (premature rupture of membranes), endometritis(infection of the endometrium), chorio-amnionitis.
- pre eclampsia/ eclampsia
- placental abruption
- HELLP syndrome
- retained dead fetus
- amniotic fluid embolus
- DIC
- liver disease: AFLP, pregnancy can cause fatty liver disease - so clotting factors not produced as well
Platelet abnormalities
- gestational thrombocytopenia
- idiopathic/immunological thrombocytopenia purpura.
- HELLP syndrome
- sepsis
- DIC from all the above causes
how is obstetric haemorrhage managed in theatre? what staff needed?
- midwife
- labour ward coordinator
- neonatal team
- 2 obstetric surgeons
- 2 anaesthetists
- 2 theatre nurses
- 2 anaesthetic assistants
- support worker to take blood tests to labs and fetch blood and blood products.
what equipment is there to help with obstetric haemorrhage?
- rapid infuser - rapidly induces and importantly warms crystalloid, celluloid and blood: ability to keep up with rapid blood loss. Can give 1L of fluid in 2 minutes.
- red cells salvage - collects and processes maternal blood from surgical site, centrifuges, washes and returns red cells to patient.
- point of care testing - ROTEM thromboeslastomerty tests whole blood clotting: guides blood product. Blood gas analyser; guides resuscitation and blood. - allows to individualise whether to give blood products or not.
what pharmacological agents can manage obstetric haemorrhage?
uterotonic agents (syntocinon IV (synthetic oxytocin), ergometrine IV/IM (very good but has side effects, causes vasoconstriction so if have pre eclampsia can cause stroke|), carboprost (can cause broncho-constriction so don’t give to asthmatics) , misoprostol
what is a cheap drug that is effective to stop bleeding?
tranexamic acic
found on the woman trial
what surgical treatments are there for obstetric haemorrhage?
for tone - uterine massage, B lynch suture (dissolving sutures hold the uterus together contacted), Bakri balloon insertion (the balloon compresses placental bed and stops bleeding)
Tissue - remove retained products, manual removal of placenta
Trauma - surgical repair
haematological managegement of obstetric haemorrhage
- replace circulating volume - Hartmans solution
- replace blood: cell salvage/ allogenic
- correct coagulation with blood products. (platelets, FFP, cryoprecipitates, fibrinogen concentrate)
what blood products are made from centrifuged blood?
Fresh Frozen Plasma.
FFP contains all of the clotting factors normally found in blood at the normal concentrations
Cryoprecipitate is prepared from FFP and contains clotting factors in higher concentrations.
Platelets are prepared by centrifuging the blood more slowly and pooling them together
what are the aims for haematological parameters when managing obstetric haemorrhage?
Maintain Hb > 8g/dl (normal range 10 to 15g/dl)
Haemotocrit > 0.3 (normal range 0.28 – 0.4)
Prothrombin time < 1.5 times normal (12-13 seconds)
Activated prothrombin time < 1.5 times normal
Platelets > 75 X 109/ litre (normal range 150-400)
Fibrinogen > 2 g/litre (normal range 3.7 – 6.2)
what bedside test and laboratory tests are done when managing obstetric haemorrhage?
Bedside testing: Serial blood gases Hb / Hct Lactate / PH / HCO3 Bedside coagulation testing: ROTEM Laboratory tests: FBC / coag (take 1 hour)
