Obstetrics Flashcards
A pregnant lady with pain in her supra pubic area that radiates to the upper thighs which is worse on walking is likely to be suffering from which common condition?
Symphysis pubis dysfunction
Can be seen with a waddling gait
Tx is supportive
What does HELLP syndrome stand for?
Haemolysis
Elevated liver enzymes
Low platelets
What is the main risk factor for uterine rupture in pregnant women?
Previous C section
What is the most effective infusion to prevent convulsions in those with pre eclampsia?
Magnesium sulphate
What drug is a synthetic prostaglandin that can be used to induce labour?
Misoprostol
Bishops scored is used for what?
Used to assess the favourability of the cervix for labour, or whether induction will be required
How does blood pressure change during each trimester of pregnancy?
Diastolic BP falls in trimester 1 and 2 due to fall in peripheral vascular resistance due to increased progesterone (CO increases in response to this)
Rises again by trimester 3
Systolic BP is unchanged
At approximately which gestation do mothers feel the foetus moving?
Approximately 16 weeks for parous women, and 20 weeks in first time mums
When should the fundus be palpable at the xiphisternum?
Approximately 38 weeks gestation
When should the fundus be palpable at the umbilicus?
20 weeks gestation
Where should the fundus be palpable at 12-14 weeks gestation?
Pubic symphysis
How does an increase in progesterone during pregnancy affect the gastrointestinal tract?
Smooth muscle relaxation reduces gastric motility so constipation
Can also causes relaxation of the gallbladder leading to biliary stasis and gallstones and possibly cholecystitis
What are the blood sugar readings to diagnose gestational diabetes in a pregnant women?
> 5.6mmol/L random fasting glucose
>7.8 mmol/L 2 hour plasma glucose
When can chorionic villus sampling and amniocentesis be offered?
CVS from 10 weeks
Amniotic fluid sampling from 15 weeks
Can warfarin be taken during pregnancy and breast feeding?
Not during pregnancy due to teratogenicity
Can be taken during breast feeding as it doesn’t pass into the milk
What are some differentials for abdominal pain in a pregnant lady?
Appendicitis, cholecystitis, HELLP syndrome, ectopic, miscarriage, ovarian torsion, MSK, fibroid, gastroenteritis, UTI/ pyelonephritis, Labour
When can external cephalon version be offered for women with babies presenting breech?
From 36 weeks in nulliparous women
From 37 weeks in parous women
Gestational hypertension occurs after what gestation?
20 weeks
Pregnant women with hypertension before 20 weeks are likely to have pre existing hypertension
At which scan is the estimated delivery date confirmed?
12 week scan
What is Naegele’s rule?
Estimation of EDD by using:
First day of LMP + 1yr7days - 3 months
What syndromes does the combined test screen for?
Trisomy 21 (down’s) Trisomy 18 (Edwards) Trisomy 13 (pateu’s)
When is the combined screening test performed?
By the end of the first trimester, between 11 weeks and 13weeks 6 days
What does the combined test use?
Nuchal translucency, PAPP A, beta-hCG, woman’s age
What does the quadruple blood test screen for?
Trisomy 21 only
In what circumstance would the quadruple blood test be offered to expectant mums?
If they are late bookers (after 14 weeks)
Or if it was not possible to measure the nuchal translucency e.g. due to baby’s position
What does the quadruple blood test use?
Mums age + AFP + oestriol + beta-hCG
When are RhD-ve women offered anti-D?
Prophylactic doses at 28 and 34 weeks
Prophylactic doses also if sensitising event e.g. ECV, diagnostic testing, abdominal trauma, antepartum haemorrhage
Post natal dose if baby is found to be RhD+ve after birth
Given to women after TOP/ ectopic/ late miscarriage
From what gestation can CTG scanning be performed?
From 32 weeks
Why are pregnant women more predisposed to UTIs?
Relaxation of smooth muscle under influence of progesterone
Does GFR change during pregnancy?
Increases, due to increased blood flow
How does the respiratory system physiologically adapt to pregnancy?
Tidal volume increases to meet increasing oxygen demands
Sense of dyspnoea due to upwards displacement of diaphragm ( but lung capacity still same due to transverse and AP diameters of the thorax)
When is pre-eclampsia seen during pregnancy?
After 20 weeks gestation
Define primary post partum haemorrhage
The loss of >500ml blood <24 hours after delivery
What is the most common cause of primary postpartum haemorrhage?
Uterine atony
What are some risk factors for primary postpartum haemorrhage?
4 T’s = tone, tissue, trauma, thrombin
= uterine atony, retained placental tissue, trauma e.g. Csection/ instrumental delivery, thrombin e.g. HTN/ pre eclampsia/ Von Willebrands/ HELLP/ DIC
What drugs can be of use in primary postpartum haemorrhage?
Syntocin
Carboprost
What are the management options for primary postpartum haemorrhage?
Stabilise (ABCDE) IV syntocin IM carboprost Intrauterine balloon tamponade B Lynch suture Uterine artery ligation Hysterectomy
What is the cause of secondary postpartum haemorrhage?
Retained placental tissue or endometritis
How is secondary postpartum haemorrhage managed?
Antibiotics
Utertonic drugs e.g. syntocin, carboprost, misoprostol
Surgery only if prolonged
When would carboprost be contraindicated?
In women with asthma
How would you manage a patient with obstetric cholestasis?
Lifestyle advice eg fans, loose clothing, aloe vera
Antihistamines to control itch
Emollients for itch
Ursodeoxycholic acid for relief of itch and to improve LFTs
Induction of labour recommended at 37/ 38 weeks gestation
When should the COCP be stopped prior to elective surgery?
Stop 4 weeks before surgery and start 2 weeks after
Other than persistent vomiting, what other signs/ symptoms must be present for it to be diagnosed as hyperemesis?
Dehydration Weight loss (>5% of pre-pregnancy weight) Electrolyte disturbance (low sodium, potassium, ketosis)
Which antiemetic is first line in hyperemesis?
Cyclizine
Which antibiotic is used in women with PPROM?
Erythromycin
Which antibiotic is the choice for GBS prophylaxis?
Benzylpenicillin
What is the management of a pregnant woman who has a history of VTE?
High risk so: LMWH throughout pregnancy until 6 weeks post natal
What medication should a woman at moderate/ high risk of pregnancy eclampsia be prescribed?
Aspiring 75mg OD from 12 weeks until birth
How much folic acid should a woman take during pregnancy?
400mcg until week 12 (5mg is higher risk of NTD eg Hx of NTD, anti epileptic drugs, coeliac, diabetes, thalassaemia, obese)
Coombs test will be positive in what?
ABO incompatibility and Rh incompatibility
Which screening tool is used to screen for postnatal depression?
Edinburgh postnatal depression scale
What is the most common cause of early onset infection in a neonate?
Group B strep
What are the stages of labour?
1: contractions, cervix effacement and dilatation
2: foetal delivery (passive stage with complete cervical dilatation but no pushing, then active stage with pushing)
3: delivery of placenta
What is placenta praevia?
When the placenta lies in the lower uterine segment
What re some risk factors for placenta praevia?
Previous CS, multiple pregnancy, increasing maternal age, assisted conception, fibroids, endometritis
How will the present of placental abruption differ to that of placenta praevia?
Placental abruption is painful, uterus is woody and tense, shock not in keeping with the blood loss, foetal heart may be distressed, lie and presentation normal
Placenta praevia is not painful and uterus is not tender, usually presents will small bleeds before large and foetal heart is usually normal, often abnormal lie and presentation
What are some risk factors for placental abruption?
Transverse lie Multiple pregnancy Previous abruption Abdominal trauma Polyhydramnios Smoking/ drug abuse Pre-eclampsia
What is vasa praevia?
When umbilical vessels run near internal cervical os and will bleed following membrane rupture
What are some indications for the induction of labour?
Maternal health complications Prolonged gestation PROM (>37 weeks) Foetal growth restriction Intrauterine foetal death
What methods are available to induce labour?
Prostaglandins (pessary/ gel/ tablet)
Membrane sweep
Amniotomy
How would you diagnose premature rupture of membranes?
Speculum will show pooling of fluid in the posterior fornix
If in doubt, can do actim-PROM swab (tests for insulin like growth factor which is 1000x times higher in the amniotic fluid)
What is tocolysis?
Medication to stop uterine contractions
Nifedipine is the medication of choice
How would you manage a pregnant woman with premature rupture of membranes who is less than 34 weeks gestation?
Erythromycin
Corticosteroids
Advise to avoid sex
Expectant management to increase gestation
What is the gestation difference to differentiate between PROM and PPROM?
PPROM <37 weeks
PROM 37 weeks onwards
What are some risk factors for PPROM/ PROM?
Infection Cervical insufficiency Smoking Previous PROM Invasive procedure Polyhydramnios Multiple pregnancy
How would you manage a pregnant woman with premature rupture of membranes who is >36 weeks gestation?
Wait for labour to start on its own, then opt for induction after 24-48 hours (risk of infection greater than benefit of foetus being in utero)
How would you advise a patient to take ferrous sulphate tablets?
Advise to take with orange juice (improves absorption) on an empty stomach one hour before a meal
What does active management of the third stage of labour involve?
Empty her bladder
IM syntocinon infusion once baby is born
Clamping and cutting of the cord within 1 minute of birth
Traction to cord and pressure on abdomen to prevent uterine prolapse whilst the placenta is delivered
Checking of the placenta to ensure no retained tissue
What management of necessary in the case of cord prolapse?
Emergency C section
Define gravidity and parity?
Gravidity is the number of pregnancies a woman has had, including her current one
Parity is the number of viable deliveries a woman has had (>24 weeks, or before if there was sign of life)
How can you gets for premature rupture of membranes?
Usually clinical diagnosis based on Hx and pooling of fluid seen in posterior vaginal fornix on speculum
If unsure, can do actim-PROM swab which measure insulin like growth factor (1000x times higher in amniotic fluid)
What physiological changes happen to the CVS system during pregnancy?
Progesterone is a vasodilator so this reduces systemic vascular resistance which decreases diastolic BP in T2 and T3
HR, SV, CO increase
Total blood volume increases due to RAAS activation increasing sodium and water retention
How would you manage a pregnant woman confirmed to have premature rupture of membranes?
Test for GBS (if +ve: benzylpenicillin) Erythromycin 10 days If >36 weeks then induction of labour <34 weeks steroids, avoid sex, expectant mx 34-36 induction and steroids
What are some side effects of oxytocin infusion?
Nausea
Slow heart rate
Raised BP
Painful contractions
What analgesic is often used in labour?
Entonox
Pethidine IM injection
Epidural
How is shoulder dystocia managed?
Call for help
Advise mum to stop pushing
Episiotomy
First line:
McRoberts manoeuvre (knees to chest which widen pelvic outlet)
Suprapubic pressure (disimpact baby’s shoulder from the pubic symphysis)
Second line:
Posterior arm (insert hand and grap posterior arm to deliver)
Corkscrew manoeuvre (move baby 180 degrees)
After delivery:
Active mx of third stage
PR exam to exclude third degree tear
What does the anterior foetal shoulder become impacted against in shoulder dystocia?
Pubic symphysis
What is the McRoberts manoeuvre for shoulder dystocia?
Bring the woman’s knees to her chest
Also additionally apply suprapubic pressure to free the baby’s shoulder from the pubic symphysis to increase success
What are some risk factors for shoulder dystocia?
Diabetes, previous should dystocia, macrosomic foetus, BMI>30, oxytocin infusion, prolonged first stage, prolonged second stage, assisted vaginal delivery, induction of labour
A perineal tear that involves the anal sphincter is what degree?
3rd of 4th
What are some complications of shoulder dystocia?
Mum: perineal tear, post partum haemorrhage, psychological trauma
Baby: Erb’s palsy, cerebral hypoxia (cerebral palsy), fracture to clavicle or humerus
What are some pregnancy complications that are more common with twins?
Preterm delivery Pre eclampsia Gestational hypertension Gestational diabetes Fe deficiency anaemia Placenta praevia Placental abruption
What are some risk factors for uterine atony?
Maternal: age >40, BMI>35, Asian
Uterine over distension: polyhydramnios, multiple pregnancy
Labour: induction, prolonged (>12hrs)
Placental: praevia, abruption, previous PPH
How would you manage a woman with primary postpartum haemorrhage?
Resuscitate: oxygen, cross matched blood (or O-) and fluids
Definitive mx:
1st bimanual compression
Drugs: IV oxytocin infusion 10 units or IV ergometrine/ then carboprost/ misoprostol
Surgery: intrauterine balloon tamponade, B Lynch suture, internal iMac artery ligation, hysterectomy
What is ergometrine contraindicated in?
Hypertension and pre- eclampsia
Causes hypertension as a side effect
When would carboprost be contraindicated?
Asthma, cardiac disease
How is primary postpartum haemorrhage risk reduced?
Active management of the third stage of labour
(vaginal delivery: IM oxytocin 5-10 units)
(C-section IV oxytocin 5 units)
What is the first line surgical intervention in primary postpartum haemorrhage, if medical options have failed?
Intrauterine balloon tamponade
What causes secondary post partum haemorrhage?
Endometritis infection or retained tissue
What is the definition of secondary post partum haemorrhage?
Excessive vaginal bleeding from 24 hours to twelve weeks postpartum
How is secondary post partum haemorrhage treated?
Antibiotics and uterotonics
(Ampicillin and metronidazole, add gentamicin if septic)
(Syntocinon, synometrine, carboprost, misoprostol)
If still bleeding: surgical interventions (balloon tamponade)
What are some causes of PV bleeding during the first trimester of pregnancy?
Miscarriage
Ectopic
Molar pregnancy
What are some causes of bleeding in the third trimester of pregnancy?
Bloody show Placenta praevia Placental abruption Vasa praevia (Do not perform vaginal exam if suspected antepartum haemorrhage)
What are the antibiotics indicated in secondary post partum haemorrhage?
Ampicillin and metronidazole
Add gentamicin If septic
What does foetal blood smoking detect?
Detects foetal hypoxia
If pH less than 7.2, emergency C section indicated
What are some complications of an instrumental delivery?
Cephalohaematoms, skull fracture, facial nerve palsy, retinal haemorrhage, 3rd/ 4th degree tears, VTE, PPH
What is the classic triad of vasa praevia?
Rupture of membranes with painless vaginal bleeding and foetal bradycardia
When should a booking visit be done in pregnancy?
8-12 weeks, ideally before 10 weeks
What antiemetic is first line in pregnancy?
Cyclizine
What are some risk factors for pre-eclampsia which would warrant prophylactic 75mg aspirin from 12 weeks until birth?
One high risk or 2 moderate risk factors
High risk: previous Hx of pre-eclampsia, chronic HTN, diabetes, autoimmune disease, renal Disease
Moderate risk: 1st degree relative with pre-eclampsia hx, nulliparity, age>40, gap of at least 10 years before pregnancy, BMI>35, multiple pregnancy
How long should an IV magnesium sulphate infusion be continued for in a woman with eclampsia?
For 24 hours after delivery or after their last seizure
How do we managed hyperemesis gravidarum?
Mild: oral rehydration, diet advice, Antiemetic (1st cyclizine or chlorpromazine)
Unable to keep food down: admit for IV normal saline and add KCl depending on electrolytes, thromboprophylaxis with LMWH
Add thiamine if deficient
Conservative/ mild cases: ginger, wrist acupuncture
What is an alternative drug to metformin for gestational diabetes?
Glidenclamide
What are some indications for a C section?
Placenta praevia Foetal distress Maternal choice Breech at term Macrosomia Previous shoulder dystocia Primary genital herpes HIV with high viral load Cervical Ca Multiple pregnancy when one is malpositioned
What are some reasons for failure to progress during labour?
3 P’s (=power, passenger, passage) Inadequate uterine contractions Macrosomia Malpositioned or malpresented Inadequate pelvic
How would you assess whether a woman is in pre term labour or not?
Assess cervical length (if >15mm unlikely to be in labour) Fibronectin assay (-ve indicates unlikely to be in labour)
How would you manage mastitis?
Analgesia
10-14 days flucloxacillin
Encourage breastfeeding out of affected breast too
Breast feeding support groups and help hotlines
What contraceptive can be used for a woman who gave birth 1 month ago?
POP
COCP CI If breast feeding
IUS or IUD can be inserted after 4 weeks
What steroid is given in PPROM and why?
Betamethasome IM, 2 doses 12-24 hours apart
Reduces chance of RDS by promoting foetal lung maturity
What features are used to calculate the Bishops score?
Dilatation Cervical length Consistency Station Position
Bishops score greater than what indicates favourable for induction?
5
Above 9 indicates will start spontaneously
What are some complications of an oxytocin infusion?
Uterine hyperstimualtion (excessive contractions can cause foetal distress hence CTG monitoring)
Uterine rupture If C section previously, hence CI
PPH
Water intoxication (ADH like effects, so restrict infusion volume)
Also short term nausea, increased BP (in mum, low in baby) arrhythmia, anaphylaxis
What chest x Ray findings are characteristic of respiratory distress syndrome?
Widespread opacification “ground glass”
Air bronchogram
Indistinct heart border
ET tube if in situ
What are some complications of Clomifene treatment?
Multiple pregnancy
Increased risk of ovarian Ca, hence tx use restricted to 12 months
Ovarian hyperstimulation syndrome (ovarian enlargement, cysts, bloating,increased risk of VTE)
What is the mechanism of action of clomiphene?
Oestrogen antagonist (therefore prevents normal -ve feedback on HPA axis so more GnRH is released)
