Late pregnancy problems Flashcards
Definition of gestational hypertension
High blood pressure after 20 weeks gestation with no proteinuria over 0.3g/day
Definition of Pre-Eclampsia
High blood pressure during pregnancy plus proteinuria of greater than 0.3g/day. Occurs after 20week gestation.
Definition of eclampsia
Convulsions/seizures plus pre-eclampsia
Risk factors for pre-eclampsia
Maternal age over 40yrs Chronic HTN CKD Autoimmune conditions e.g. SLE, antiphospholipid syndrome Previous pre-eclampsia First pregnancy Type 1 or 2 DM High BMI Multiple pregnancy
Pathophysiology of pre-eclampsia
Inadequate spiral artery invasion in the myometrium. This means less blood can get to the baby and so the mother’s body responds by increases the blood pressure to get more blood there.
Values for high blood pressure during pregnancy
HTN in pregnancy = SBP >140mmHg, DBP >90mmHg
Severe HTN = 160/110mmHg or more
Symptoms of pre-eclampsia
Severe headaches
Visual disturbance (blurred, double, floating spots)
Persistent epigastric or right upper quadrant pain.
Vomiting
Breathlessness
Swelling of hands, feet, face.
Brisk reflexes
HELLP syndrome
Haemolysis, Elevated Liver enzymes, and Low Platelets syndrome.
Treatment of mothers at high risk of pre-eclampsia
Daily aspirin (75mg) from 12 weeks gestation until birth and advice on lifestyle.
Those at high-risk =
Previous pre-eclampsia
DMT1 or T2
CKD
Chronic HTN
Autoimmune disease e.g SLE or antiphospholipid syndrome.
Management of established pre-eclampsia
Start med if BP over 150/100mmHg –> Labetalol, nifedipine
Monitor mum and baby!
ACEi contraindicated in pregnancy!!!!!
Monitor mum post-natally!
Management of eclampsia
ABCDE
IV magnesium sulphate - bolus dose then maintenance dose.
Fetal CTG
C-section delivery
Cut off gestational age for steroid use and commonly used steroid
Only use if less than 34 weeks gestation. Dexamethasone.
Complications of pre-eclampsia
Maternal = Intracerebral haemorrhage/stroke, Eclampsia and seizures, pulmonary oedema, acute renal failure and hepatic failure. Baby = placental abruption, IUGR, premature delivery, intrauterine death, PPH, oligohydramnios
Risk factors for venous thrombosis in pregnancy
Previous VTE maternal age over 35yrs. High BMI Smoker Multiple pregnancy Pre-eclampsia Greater than 4 parity Immobility
Why is VTE risk increased in pregnancy?
More blood stasis and altered protein balance.
Causes of an antepartum haemorrhage
Placenta praevia - painless Placenta abruption - painful Vasa praevia - painless Uterine rupture Still birth? Cervical poly Cervical carcinoma
Definition of an antepartum haemorrhage
PV bleeding after 24weeks gestation.
Definition of placenta praevia
Placenta is implanted in the lower segment of the uterus, below fetal presenting part.
Types of placenta praevia
Marginal = not covering but encroaching on os. Major = partially or completly covering os.
Clinical features of placenta praevia
Painless and recurrent PV bleeding. Baby usually in abnormal presentation/lie
Diagnosis of placenta praevia
Transvag USS. In 2nd scan at 20 weeks, if low lying placenta is seen, book for third trimester (34weeks) scan to follow-up and diagnose.
Cross-match blood type.
Management of placenta praevia
Up to 34weeks gestation can offer corticosteroids.
Plan delivery for before 39weeks gestation via c-section
Prepare ant-D immunoglobulins and blood transfusion if appropriate.
Complications of placenta praevia
PPH, placenta accreta or percreta.
Risk factors for placenta praevia
Previous placenta praevia. Previous c-section deliveries. Advanced matermal age (over40). Smoking. Previous terminations of pregnancies. IVF and assisted conception.
Placenta abruption definition
Premature detachment of placenta from the uterus and blood dissects under the placenta before delivery of the fetus.
Risk factors for abruption
Abruption in previous pregnancy. Pre-eclampsia IUGR polyhydramnios low BMI Advanced maternal age IVF Non-vertex presentation. Abdo trauma Substance misuse and smoking.
Clinical features of placenta abruption
Bleeding PV
Constant abdo pain, pain and shock of mum may be disproportionate to visible loss of blood = concealed haemorrahge.
Woody-hard, tense and tender uterus on palpation.
Investigations for placenta abruption
Fetal monitoring via CTG
Maternal TV USS, cross-match blood, FBC for anaemia, monitor urine output, urinalysis.
Management of placenta abruption
ABCDE
Anti-D antibodies if appropriate and blood transfusion.
Steroids may be given if below 34weeks gestation.
If fetal distress C-section, if no distress vaginal delivery possible.
Vasa praevia definition
Fetal blood vessels lie on the membranes that cover the internal cervical os.
Complications of vasa praevia
When membranes rupture vessels can haemorrhage and rupture too - fetal blood loss!
Presentation and management of ruptured vasa praevia
Painless, PV beeding on membrane rupture. Fetal bradycardia. URGENT C-SECTION but fetal mortality is high
treatment of VTE in pregnancy and time of highest risk
Low molecular weight heparin. Warfarin can cross placenta.
Monitor anti-Xa
Most occur post-partum
Polyhydramnios defintion
Too much amniotic fluid in the amniotic sac
Pathophysiology of polyhydramnios
Poor swallowing of fluid by fetus, poor absorption of fluid inside baby, increased secretion of fluid by placenta.
Causes of polyhydramnios
Fetal malformation - spina bifida, atresia of GI tract in fetus. Multiple pregnancy Maternal diabetes mellitus. Fetal anemia. Infections such as rubella, CMV.
Clinical features of polyhydramnios
Over distended uterus
Symphyseal-fundal height larger than dates
Faint or indistinct fetal heart rate.
Maternal dyspnoea, oedema.
Treatment of polyhydramnios
Amniocentesis (removing fluid)
Laser ablation of communicating vessels for twins.
Complications of polyhydramnios
Preterm labour
Premature rupture of membranes
Umbilical cord prolapse
PPH
Oligohydramnios
Too little amniotic fluid in amniotic sac. Less than 500ml in 32-36weeks gestation.
Causes of oligohydramnios
Rupture of amniotic membranes. Fetal urinary tract malformations. IUGR Placenta abruption Maternal dehydration
Management of oligohydramnios
Delivery baby if poss.
Consider prophylactic erythromycin.
Amnioinfusion (only special circumstances!)
Complications of oligohydramnios
Pulmonary hypoplasia - wry neck, club foot.
Amniotic band syndrome.
Normal fundal height growth
After 24 weeks you would only expect the fundal height to increase by 1cm a week.
Antidote for magnesium sulphate induced respiratory depression
Calcium gluconate is first-line treatment
DIC
Disseminated intravascular coagulation
Causes of DIC in pregnancy
Placenta abruption Pre-eclampsia HELLP Amniotic fluid embolism Retained products of a dead fetus (after 20weeks gest) Placenta accreta Hydatidiform mole
Pathophys of DIC in pregnancy
Intravascular clotting consumes platelets and fibrin. Pathogenic release of thrombin and thromboplastin into circulation.
Investigations and results for DIC in pregnancy
Long APTT Long prothrombin time Low platelets Low fibrinogen High D-dimer and products of fibrin breakdown.
Management of DIC in pregnancy
O2 Blood crossmatch Blood transfusion (fresh) Platelet transfusion Consider calcium gluconate
Routine investigations for pre-eclampsia mum
Blood pressure (obvs)
Urinedip (proteinuria)
FBC (low platelets and haemolysis in HELLP)
Renal function = U+E, protein-creatinine ration, GFR
LFT (AST and transaminase for HELLP)
Pathophysiology of Rhesus disease
If mother is Rhesus -ve and father is Rhesus +ve then offspring can be Rhesus +ve.
First pregnancy with a Rhesus +ve fetus in mother allows memory cells for Rhesus +ve antigen to be produced. These are IgG so can cross the placenta and affect future babies. However in first pregnancy the immune system only uses IgM antibodies which wont cross placenta.
What happens to babys with Rhesus disease
RBC haemolysis causes anaemia.
Prophylaxis for Rhesus disease
Anti-D. This destroys the anti-rhesus +ve antibodies in mother. Given at 28-34 weeks and after birth/
What does asymmetrical intrauterine growth restriction (normal head circumference with reduced abdominal circumference) suggest?
Placenta insufficiency however, if both the head circumference and abdominal circumference are low then more likely chromosomal abnormality.
Causes of antepartum haemorrhage
Placenta abruption
Placenta praevia
Vasa praevia
Morbidly adherent placenta (accreta, increta, percreta)
Pathophysiology behind the seizures in pre-eclampsia
Proteinuria leads to hypoalbuminaemia. This causes oedema and fluid leves vessels (hypovolaemia). Brain is not adequately perfused = seizures.
