Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
48 Cards in this Set
- Front
- Back
What is the definition of true labour?
|
false labour pains become more coordinated and regular or "show" is seen or cervix is at least 2cm
|
|
How do you determine head station?
|
= level of lwest fetal bony part (head or breech) in relation to imaginary line across ischial spines (-5 = more proximal, 0 - at ischial spines (engaged) +5 more distal)
Antepartum - how many fifths of the head are felt - Ifyou think you're at the widest part of the head it is 3/5 |
|
What are the different types of rupture of membranes?
|
Rupture of membranes
Premature - at least 1 hr prior to onset of labour Prolonged premature - > 18 hours elapse between rupture of membranes and onset of labour preterm - ROM occurring before 37 weeks gestation Preterm premature - ROM before 37 weeks AND prior to onset of labour |
|
What investigations should be done to confirm rupture of membranes?
|
Sterile speculum exam - pooling of fluid in the posterior fornix, may observe fluid leaking out of cervix on cough
Amniotic fluid turns nitrazine paper blue (alkaline; vaginal - acidic) ferning (high salt in amniotic fluid evaporates, looks like ferns under microscope) US to rule out fetal abnormalities - oligohydramnios is indicative of ROM |
|
Describe the 1st stage of labour?
|
1
Latent: - uterine contrasctions typically infrequent and irregular - slow cervix dilation (usually 3-4cm) and effacement - usually ROM at end of latent phase Active phase - rapid cervical dilation to full dilatation - should increase by 0.5-1cm/hr for nulliparous woman - painful, regular contractions, q2min, lasting 45-60 secs - contractions strongest at fundus, weakest at lower segment - unwise to push at this stage even if pt feels like it |
|
Describe the 2nd stage of labour?
|
from full dilatation to delivery of the baby
Mother feels a desire to bear down and push with each contraction Uterine contractions @ 2-5mins |
|
Describe the 3rd stage of labour?
|
From birth of baby to placenta expulsion
Separation usually complete within 5 minutes but can last up to 30mins before intervention is indicated 2 methods - expectant or active Active - give IM 10 IU Syntocin) when anterior shoulder is delivered or within 1-2 mins of the birth of the baby |
|
Describe the 4th stage of labour?
|
First postpartum hour
Monitor vital signs and bleeding repair lacerations ensure uterus is contracted (palpate uterus and monitor uterine bleeding) |
|
What are the 4 signs of placental separation?
|
Gush of blood
lengthening of the cord uterus becomes globular fundus rises |
|
Describe the cardinal movements of the fetus during delivery
|
Engagement, descent, flexion (allows smallest diameter to present to the pelvis)
Internal rotation (to OA ideally) Extension of the head as vertex passes public symphysis it extends to deliver Restitution (external rotation) once the head is through the vagina to allow delivery of shoulders, anterior then posterior shoulder |
|
Describe the role of CTG?
|
Cardiotocography
Doppler device which measures fetal heart rate Establishes a baseline and shows variation in the HR during labour Can be lost during contraction as the fetal position changes |
|
When should a fetal scalp electrode be used? How does it work?
|
used if repetitive decels or difficulty in tracing externally with a doppler
Senses potential differences caused by depolarisation of fetal heart More sensitive CI: HIV, hepatiis, fetal thrombocytopenia |
|
What is a normal fetal HR?
|
110-160
Any bradycardia below 90bpm for more than 2 mins is of concern and requires immediate action |
|
What are the reassuring aspects of a foetal trace?
|
Baseline between 110-160
Beat to beat variability > 5bpm between contractions At least 2 accelerations of at least 15 bpm over the baseline for at least 15 seconds every 10 mins No form of deceleration (drop in bpm by 15 beats for more than 15 secs) is reassuring |
|
What is an early deceleration?
|
Uniform shape with onset early in contraction and returns to baseline by end of contraction
Normal vagal response to head compression Benign usually seen with cervical dilation of 4-7 cm |
|
What are variable decelerations?
|
Variable in shape, onset, and duration
Most common type Due to cord compression or forceful pushing with contractions Benign unless repetitive, with slow recovery or when associated with other abnormalities of FHR |
|
What are late decelerations?
|
Uniform shape with onset late in contraction, lowest depth after peak of contraction, return to baseline after end of contraction
must see 3 in a row with all the same shape to define a late deceleration Due to fetal hypoxia, and acidemia, maternal hypotension or uterine hypertonus usually an ominous sign of uteroplacental insufficiency |
|
What suggests a severe variable deceleration?
|
Deceleration to < 60bpm
> 60bpm beflow baseline > 60 s in duration with slow return to baseline |
|
When should foetal scalp blood sampling be used?
|
Indicated when non-reassuring fetal hear rate is suggested by clinical parameters inc. heavy meconium, mod to severe abnormal FHR patterns
|
|
What is a normal fetal pH
Which pH indicates fetal acidosis |
> 7.25
< 7.2 - acidosis - delivery indicated |
|
Describe the different types of pain relief used in childbirth?
|
Nitrous oxide and oxygen (50:50); Give in an Entonox machine; Enhances GABA-A receptors, induces dopamine and antagonises NMDA receptors
Epidural (fentanyl and LA); most effective way of relieving pain; L3/L4 space; SE: dizziness, shivering, may increase duration of 2nd stage and increase operative deliveries, severe headache (dural tap) Pudendal block - gives perineal anaesthesia - commonly used in forceps and vacuum delivery Spinal - similar to epidural - bolus, one time dose - more common in c/s - SE: decreased sysetmic resistance --> hypotension --> decreased placental perfusion --> fetal bradycardia - can get maternal resp depression if drug affects diaphragm GA - used in emergency C/S - risk of maternal aspiration, hypoxia to fetus and mother |
|
Describe the 4 degrees of perineal tears
|
1. damage to the fourchette and vaginal mucosa and the underlining mm are exposed
2. the posterior vaginal wall and the perineal mm are torn but the anal sphincter is intact 3. the anal sphincter is torn but the rectal mucosa is intact 4. the anal canal is opened and the tear may spread to the rectum |
|
What is inducation of labour and how is it achieved?
|
Is an intervention designed to artificially initiate uterine contractions resulting in progressive effacement and dilatation of the cervix and birth of the baby
1. Cervidil to ripen cervix 2. AROM 3. Syntocinon - to start contractions |
|
List the indications for induction of labour
|
Gestation of at least 41 weeks
Evidence of fetal compromise (fetal growth restriction and/or non-reassuring fetal surveillance) maternal medical conditions (diabetes, renal disease, hypertension, sig pulm disease, antiphospholipid syndrome etc) pre-pabour rupture of membranes chorioamnionitits gestational diabetes with complications multiple pregnancy abruption macrosomia (big baby) fetal death in utero Bishop score! |
|
What are the components of the bishop score
|
Position (posterior, mid, anterior)
Consistency (firm, medium soft) Effacement (0-80) Dilatation Station of the fetal head |
|
What does a bishop socre of < 5 mean?
|
Chance of successful vaginal delivery can be only 50% with induction - need to give prostaglandin gel, pessary (cervidil) of misoprostol to "ripen" the cervix
|
|
Describe the methods for cervical ripening?
|
1. Intravaginal prostaglandin (Prostin gel): - long and closed cervix with no ROM
2. Intravaginal PGE2 (Cervidil) - long and closed cervix, may use if ROM 3. Misoprostol: synthetic methylated PGE1 (not commonly used) 4. Foley catheter placement - to mechanically dilate the cervix |
|
What does a bishop score > 7 indicate?
|
A favourable cervix
|
|
Describe the methods for induction of labour
|
Amniotomy = artificial ROM to stimulate PG synthesis and secretion
Oxytocin (Syntocinon) - |
|
Potential complications for Oxytocin to induce labour
|
hyperstimulation/tetanic contraction (may cause fetal distress or rupture of uterus)
uterine mm fatigue, uterine atony (may result in PPH) vasopressin-like action causing anti-diuresis |
|
What is augmentation of labour
|
Oxytocin to promote adequate contractions when spontaneous contractions are inadeuqate and cervical dilatation or descent of fetus fails to occur
To increase the rate of progress of spontaneous labour |
|
Risks of induction of labour
|
Cord prolapse
uterine rupture PPH requiring an epidural requiring an operative vaginal birth requiring a caesarean section |
|
CI to induction
|
Previous C/S
Previous uterine surgery If you can't monitor patient Placenta praevia or vasa praevia, cord presentation fetal distress, malpresentation, preterm fetus without lung maturity |
|
Define the terms presentation and position
|
Presentation: the part of the fetus lying over the pelvic inlet; the presenting body of the fetus
Position: the relationship of a given point on the presenting part of the fetus to a designated point of the maternal pelvis |
|
Describe the conditions which can prolong labour or delay labour?
|
Prolonged labour > 48 hours
Fault of the power: (leading cause) contractions (hypotonic, incoordinate), inadequate maternal expulsive efforts Fault of the passenger Abnormal position (e.g., OP), size of fetus, shoulder dystocia(after delivery of the head, the anterior shoulder cannot pass below the pubic symphysis) Fault of the Pelvis: reduced brim of pelvis; shape of sacrum; poor relaxation of pelvic ligaments Psyche: hormones released in response to stress can bring about dystocia |
|
Describe the disorders that are involved in abnormal progression of labour (dystocia)
|
Arrest disorder (arrest of dilatation or descent)
(Dilatation progress does not occur for > 2 hours in a patient who has entered the active phase no progress in station for > 1 hr during 2nd stage) Rx: if CPD ruled out - IV oxytocin and amniotomy can be attempted Protraction disorder ( slope of cervical dilatation is < 1.2cm/h in primigravidas or < 1.5cm/hr in mulitgravidas; rate of descent of < 1cm/h in primigravidas or 2cm/hr in multigravidas) Rx: oxytocin augmentation if contractions are inadequate +/- amniotomy Prolonged latent phase > 20 hrs in primigravidas or > 14 hrs in multigravidas during which labour has not progressed to the active phase Most often due to false labour - rest and/or sedation Rx: If labour is certain - oxytocin augmentation |
|
Describe the indications for use of an operative vaginal delivery (forceps or vacuum extraction)
|
Fetal
- non-reassuring fetal status - consider if 2nd stage is prolonged as this may be due to poor contractions or failure of fetal head to rotate Maternal - need to avoid voluntary expulsive effort (cardiac/cerebrovascular disease) exhaustion, lack of cooperation and excessive analgesia may impair pushing effort |
|
Conditions necessary for use of forceps
|
Full dilatation of cervix
Ruptured membranes Engaged head at +2 station knowledge of fetal position No evidence of CPD Adequate anaesthesia Empty bladder |
|
Complications of forceps use
|
Maternal:
anaesthesia risk; lacerations; injury to bladder, uterus, bone, pelvic nerve damage, PPH, infections Fetal: fractures, facial nerve palsy, trauma to face/scalp, intracerebral haemorrhage, cephalohaematoma, cord compression |
|
Complications of vacuum use for fetus
|
subglial haemorrhage
subaponeurotic haemorrhage soft tissue trauma retinal haemorrhage |
|
Forceps vs vacuum?
|
Forceps = higher rates of maternal trauma (perineal and vaginal lacerations), facial palsies
Vacuum = higher rates of neonatal injury ( cephalohaematomas, shoulder dystocia) Rates of complications between 2 are not significant |
|
Describe the indications for a C/S
|
Maternal:
obstruction, active herpetic lesion on vulva, invasive cervical cancer, previous uterine surgery or C/S, underlying maternal illness (eclampsia, HELLP syndrome, heart disease) Maternal-fetal: failure to progress, placental abruption or praevia fetal: NRFHR, malpresentation (e.g., breech, transverse lie), cord prolapse, congenital anomalies |
|
Describe interventions to facilitate the delivery of the placenta
|
1. Administration of uterotonic agents - oxytocin IM 10U with the birth of the anterior shoulder or within 2 mins of the birth of the baby
2. Controlled cord traction - clamp the cord within 2-3 mins of administration of an oxytocic 3. Uterine massage to make sure it is well contracted 4. As the placenta emerges gently turn it until the membranes are twisted |
|
Why are steroids given to Mum's with PPROM
|
RDS
Decrease mortality IVH NEC |
|
When are steroids given to Mum's with PPROM
|
2 doses
0 and 24 hours |
|
Why are antibiotics given to Mum's with PPROM
Which ones are given |
Decrease the frequency of maternal and fetal infections and delay the onset of labour
Give Erythromycin If GBS +ve give penicillin or clindamycin (if pen allergy) |
|
What is the main tocolytic used in Australia?
What are some other examples |
Nifidipine - main one
Also: Mg Sulfate, B2 agonists, NSAIDs |
|
Describe the investigations used to determine ROM
|
Visualise fluid coming out of cervical os
Nitrazine - test pH of vaginal fluid - amniotic 7-7.3; vaginal 3.8-4 Fern - glass slide - delicate ferning pattern cf. cervical mucous - thick and wide aborisation US - low amniotic fluid volume |