235 - Pregnancy 2 Flashcards
What is pre-eclampsia?
A pregnancy specific multi-system disorder - diffuse vascular endothelial dysfunction with circulatory disturbances. Involving renal, hepatic, cardio, CNS and coagulation systems.
What are the key signs seen in pre-eclampsia?
Hypertension
Proteinurea
HEadaches
Oedema
+visual disterbances, epigastirc + RUG pain, nausea, vomiting.
What happens to the kidneys in pre-eclampsia?
Reduced GFR proteinurea Increased serum creatinine Raised uric acid Oliguria
What is HELLP syndrome?
Serious complication of pre-eclapsia
Haemolysis, elevated liver enzymes, low platelet count
- bleeding risk + DIC
What is eclampsia?
A tonic-clonic seizure - can be fatal to mother + child
What can happen to the placenta in pre-eclampsia?
Higher abruption risk
Placental ischaemia
IUFD - fetal death
IUGR - growth restriction
What are the differentials for high blood pressure in pregnancy?
Pre-existing (due to chronic renal issues, essential high BP) Pregnancy induced hypertension Super-imposed pre-eclampsia Transient hypertension Pre-eclampsia
Why does pre-eclampsia occur?
Not fully known - some genetic risk (8x risk if sister had it, 4x risk if mum did)
? Issue with placentation in 1st half of preg .
? abnormal placentation + trophoblast invasion - poor implantation + under perfusion.
? Lack of vascular adaption to pregnancy - can’t optimise blood supply - spiral arterioles cant adapt to become high capacitance low resistance vessels.
How can you manage pre-eclampsia?
- Monitor - deliver baby
- Labetalol
- Magnesium sulphate to reduce risk of seizure
- Steroid? To increase surfactant production in baby in case of early delivery
What can cause bleeding early in pregnancy?
Miscarriage
Ectopic
What can cause bleeding late in pregnancy?
Anterpartum heamorrhage
- Placenta previa
- Placental abruption (contained or revealed)
- Placenta Accreta (firmly adherant)
- Placenta Increta (invades myometrium)
- Placenta Percreta (invades throught serosa)
- Vasa Praraevia (vessels overlie cervix)
What is a post-partum haemorrhage?
> 500ml blood from GU tract
5% of vaginal births
- Primary if 24hrs to 6 weeks after delivery (endometriosis)
What can cause PPH?
4 Ts
Thrombin - bleeding disorder, pre-eclampsia
Trauma - C/S, episiotomy, macrosomia
Tissue - Retained placenta, placenta accretia
Tone - Overdistention can cause atony
What puts you at risk of PPH?
Previous PPH, placenta previa, twins, nulliparity, obesity, pre-eclampsia
In delivery: C/S (emergency or repeat) operative birth, macrosomia
How do you manage PPH?
Check clotting + replace factors
Empty uterus
Empty bladder and rub improve tone of uterus - bimanual compression + oxytocics useful.
Repair any tears
If bleeding continues - hysteroscopy, tamponade (blow up baloon to compress outside), haemostatic sutures, arterial ligation.
When is opperative delivery needed?
Presumed fetal distress on CTG or foetal scalp sample
Maternal reasons - if valsalva manouver needs to be avoided (cardiac disease)
Inadequate progress
What specific criteria must be fulfilled to do an operative delivery?
Valid reason Head NOT palpable abdominally - must be at/below ischial spines. Cervix fully dilated Head in known position Analgesia Empty bladder ability to do c/s if needed
What are the 2 methods of operative vaginal delivery/
Ventouse - cap suctioned onto head 3cm from posterior fontanelle. complications: failute, cephalohaematoma, retinal haemorrhage and maternal worries.
Forceps: pair lock together. Non rotational. DOA is best position for this - try to rotate round to it first.
- complications: significant maternal perianal trauma.
Both carry risk of needing a c/s, low 5min apgar, phototherapy
What sort of Caesarean section is done usually?
LSCS - lower section c/s, using a Pfannesteil incision
What are some absolute indications for c/s?
Placenta previa
Abnormal lie
Pelvic deformity
Previous classical C/S - vertical scar
What increases the chances of a multiple pregnancy?
Increasing maternal age
Family history
Race
IVF
What is meant by : monozygous?
identical twins
Single zygote spolits
same genetic material
What is meant by : Dizygous?
non-identical twins
2 egg and 2 sperm = 2 zygotes
different genetic material
What is chorinicity?
Whether they share a placenta
What is amniocity?
Whether they share the same amniotic membranes
What chorionicity and amniocity can monozygous twins be?
MCDA
MCMA
DCDA
MCDA, MCMA, DCDA twins:
Which are at a high risk and of what?
MCDA and MCMA are at higher risk of misscarriage, congenital issues, IUGR and twin to twin transfusion syndrome.
When and how are multiple pregnancies delivered?
If uncomplicated DCDA: 37-38 weeks
If MCDA: 36-37 weeks
How depends on leading twin presentation + complications
Sometimes can have insufficient uterine action for twin 2
Can have foetal distress, cord prolapse or PPH
What cardiovascular changes occur during pregnancy?
Big increase in CO (30-50%)
- by increasing blood volume by 50% and increasing HR.
- uterus uses = O2 demand as kidneys
During labour CO increases by 15-50%
Post-partum CO increases by 80% as suddenly redistributed away from uterus.
Bp - varies on position more
- Peripheral vascular resistance is reduced due to progesterone effect
- Systemic Bp low in 1st 24 weeks, then increases back to normal by delivery
What haematological changes occur in pregnancy?
Blood vol increases to 5000ml due to progesterone and RAAS.
Neutropenia, low platelets, low cell mediated immunity.
RBC mass increases by 30% but blood vol by 50% - so hct and hb decrease overall in concentration.
- Alk phos, B globulin and fibrinogen increase.
- total protein, albumin and y-globlin decrease
- > abnormal LFTs and ESR and oedema.
- Prothrombotic state - increase in factors O. VII, VIII, IX, X and XII.
- protective against PPH.
- reduced pro-thrombin times as resistant to APC and protein S.
- In 3rd trimester, increase in platelet aggregation and factor VII.
What endocrine changes occur during pregnancy
Increase in RAAS - retail wanter and Na
Thyroid - Increase in Thyroid binding globulin (so less free T4, so more TSH, so more total T3 and T4)
Increased iodine requirement
In hyperemesis gravidarium - lots of hCG which binds to the TSH receptor, can cause hypothyroid.
What GI changes occur in pregnancy?
Early - nausea and vomiting common Increased appetitie, PICA, cravings Progresterone weakens LOS - reflux Reduced GI motility Gallbladder dilates and loses tone - at risk
What MSK effects happen in pregnancy?
Increased weight on joints
Softened connective tissue
Oedema - can cause carpel tunnel
What respiratory changes occur in pregnancy?
Increase in foetal O2 requirements so women increase tidal volume by 30% and reduce residual volume by 20%.
RR and capacity unchanged.
Have a compensated respiratory alkalosis to help foetal-maternal blood transfer.
Progesterone makes women feel short of breath
What urinary changes occur during pregnancy?
Kidney size increases + ureteric dilatation - increased UTI risk.
Increased renal blood flow and GFR
Altered tubular function
Increase in glycosuria, proteinuria, Ca and bicarb and creatinine clearance.
Reduced bladder capacity.
