Methods Of Delivery Flashcards
Indications for instrumental delivery
Maternal exhaustion
Non rotational forceps
Neville-Barnes (cephalic + pelvic curve)
Max of 3 contractions to deliver
Ideally spinal/epidural
Also pudendal nerve block or local anaesthetic at perineum
Risks of forceps deliveries
Failure to deliver -> Caesarean section
Vaginal tears
Fetal trauma e.g. Bruising + abrasions
Indications for elective caesarean
Previous classic caesarean
Breech with failed ECV
Placenta praevia: grade 3/4
Multiple pregnancies (if first twin not cephalic)
To prevent transmission of infection e.g. HIV + primary HSV
Must be planned before onset of labour
Not usually performed before 39 wks
Indications for emergency Caesarean section
Fetal or maternal emergency
Decision to delivery = 30 mins
Rotational forceps
Kielland’s forceps:
cephalic curve, no pelvic curve
Ventouse
Suction cap attached to
Traction + maternal effort
Can also be used where rotation required
External cephalic version
Offer to nulliparous from 36 wks, multiparous from 37 wks
50% success
Complications: placental abruption, uterine rupture, fetomaternal haemorrhage,
CI: APH in last 7 days, abnormal CTG, major uterine abnormality, ruptured membranes, multiple pregnancy
Relative CI: SGA, proteinuric pre-eclampsia, oligohydramnios, major fetal abnormalities, scarred uterus, unstable lie
1st degree tear
Injury to perineal skin only
2nd degree tear
Injury to perineum involving muscles but not anal sphincter
3rd degree tear
A. 50% ext anal sphincter torn
C. Both ext + int anal sphincters torn
4th degree tear
Injury to perineum involving anal sphincter and anal epithelium
RF for 4th degree tears
High birth weight Persistent occipitoposterior position Nulliparity Induction of labour Epidural Prolonged 2nd stage (>1hr) Shoulder dystocia Midline episiotomy Forceps delivery
Non indications for c sections
Twin pregnancy, 1st = cephalic Preterm birth SGA Hep B or Hep C without HIV Recurrent genital herpes Maternal request
Assessing fetal presentation using fetal head
Ant fontanelle = diamond
2 frontal, 2 parietal
Post fontanelle = Y shaped
Two parietal, occipital
Assessing station
0 = at ischial spines
-1 to -3 = above spines
1 to 2 = below spines
Induction of labour
Offered if > 40wks +12 days
Prostaglandins initiate contractions + encourage cervical ripening
3mg tablets, 6-8hrly, max 6 mg/day
Artificial rupture of membranes w. Amnihook
Oxytocin infusion
Complications of induction/augmentation of labour
Failure -> req operative delivery Uterine hyperstimulation >7/15 mins can cause mat + fetal distress, stop oxytocin infusion, continuous monitoring, ?tocolysis, of fetal compromise suspected deliver asap! Nausea, vom, diarrhoea: systemic SE Water intoxication Uterine rupture
1st stage labour
Latent: cervical effacement, dilation to 3 cm
Slow hrs-days
Active phase: 3-10 cm dilation
Faster hrs
2nd stage
Full dilation -> delivery
Passive: full dilation until urge to push
Active: pressure of head on pelvic floor = urge to push -> delivery
3rd stage
Delivery of fetus -> delivery of placenta
Indicated by lengthening of cord assoc with rush of dark red blood
Contraction of uterus shears placenta from uterine wall
Power
Contractions: 40-60s every 2-3 mins
Irreg contractions often seen in primips
Associated with dilation and shortening of cervix
Passage
Bony pelvis and assoc soft tissues
Inlet: transverse diameter= 13cm, AP diameter= 11cm
Outlet: transverse= 11cm, AP=13cm
Normal passage
Descent
Engagement: occipitoanterior position
Extension of head
Crowning
Restitution: external rotation on delivery of head
Lateral flexion: allows delivery of shoulders + trunk
Prerequisites for instrumental delivery
Patient consent
Valid indication
Fully dilated cervix + ruptured membranes
No abdominally palpable head
Head at or below level of ischial spines
Empty mat bladder + adequate analgesia
Determined position of head with no excessive moulding
RF for shoulder dystocia
Macrosomia Hx of dystocia Mat obesity Prolonged 1st stage Secondary arrest >8cm dilated Mid-cavity arrest Forceps/ventouse delivery
Signs suspicious of shoulder dystocia
Slow/difficult delivery of head
Neck does not appear
Turtle sign: chin retracts against perineum
Complications of shoulder dystocia
Compression of umbilical cord betw mat pelvis and fetal trunk hypoxia= fetal morbidity + mortality
Downward traction on head -> Erb’s/Klumpke’s palsy
Deliberate fracture of fetal humerus or clavicle
Maternal
Birth canal injury, femoral nerve injury, incr blood loss
Emergency management of shoulder dystocia
H: elp
E: valuate for episiotomy
L: egs into McRoberts -flex+ abduction
P: suprapubic pressure ‘mazzanti’s’
E:nter pelvis to perform manoeuvres - Rubin or Woods
R: emove posterior arm
R: oll mother over and repeat manoeuvres
Attempt each for 20-30s
Last resort= symphisiotomy, deliberate clavicle fracture, zavanelli
Cord prolapse
Assoc with artificial rupture of membranes (especially where no close fit betw presenting p and pelvic inlet), long cord, 2nd twin
Mechanical compression of cord by presenting part
Spasm of umbilical vessels due to cooling, drying, pH change and handling
CTG: deep decelerations, prolonged bradycardia
Management of cord prolapse
Help Deliver ASAP Stop any oxytocin infusion Head down position, lift presenting part PV/fill bladder Fully dilated-> attempt instrumental Not fully-> emergency Csection
Bishop score for cervical ‘favourability’
Higher = shorter + easier
Subject to examiner variation, same person should assess progress
Dilation: 4
Consistency: firm : average : soft
Length: >4 : 2-4 :1-2 : 1
Uterine inversion
Rare
Fundus passes through cervix into vagina
Stretch on round ligament-> vagal stimulation-> profound shock
Shock out of proportion with blood loss, fundus not abdominally palpable - blue grey mass in vagina
RF: fundal placenta, atomic uterus, prev inversion
don’t attempt to remove placenta prior to signs of placental separation, gentle traction + counter pressure on uterus
Consenting for c section
Serious risks: hysterectomy 0.7-0.8%, further surgery at later date 0.5%, ICU admission 0.9%, bladder injury 0.1%, ureteric injury 0.03%, fetal laceration 2%, incr risk uterine rupture in subsequent pregnancies 0.4%, antepartum stillbirth 0.4%, incr risk placenta praevia or acreta in subsequent pregnancies 0.4-0.8%
Frequent risks: persistent wound and abdominal discomfort in first few months following surgery, incr risk of further c section in future
Other procedures: blood transfusion, repair of bladder/bowel damage, surgery on major vessels, ovarian cystectomy/oophorectomy,mif unsure cited pathology is found, hysterectomy
Urgency of c section
Grade 1: immed threat to life of women or fetus
Grade 2: maternal/fetal compromise, not immediately life threatening
Grade 3: no maternal or fetal compromise but needs early delivery
Grade 4: timed delivery to suit woman or staff
Uterine rupture
Scar tenderness between contractions, cessation o contractions
Abdo pain ++ mat tachycardia, CTG abnormalities, PV bleeding
RF: prev uterine surgery, use of prostaglandins and oxytocin, prev classical c section!!! ECV, uterine malformation, obstructed labour, shoulder dystocia, forceps
3rd stage >30 mins
Manual removal of placenta in theatre may be required
Conservation: leave placenta in situ to be absorbed
Haemorrhage with manual removal -> suction curretage
Massive haemorrhage -> hysterectomy
Risks of Caesarean section
VTE: 4-16/10,000 Significant haemorrhage: 5/100 Damage to bladder: 1/1000 Req hysterectomy: 8/1000 Death 1/12000 1-2% babies suffer lacerations Infection: 6% 2x risk of stillbirth in subsequent preg Incr risk placenta praevia
Remifentanil
Infusion pump
When epidural/spinal CI
Pethidine/Diamorphine
?
Entonox
Adjunctive analgesia
Epidural
?
CI to epidural
Absolute: allergies, systemic infection, skin infection at site, bleeding disorders, plt
Branches of pudendal nerve
Inferior anal
Inferior haemorrhoidal
Dorsal nerve of clitoris
