Principles of operative delivery and C-section Flashcards
What are the types of operative deliveries?
Instrumental assisted vaginal deliveries
* Ventouse (vacuum) extraction
* Forceps
Abd delivery
* C-section: lower segment/ classical (upper segment)
If we want to deliver baby before the natural onset of labor, how can we achieve delivery?
- Induce labour (methods: prostaglandin, or amniotomy, or syntocinon, or amniotomy together with syntocinon)
- Caesarean section
What is a episiotomy?
Indications?
Surgical approaches?
Anesthesia needed?
Complications
- Surgical incision of the perineum made to increase the diameter of the vulval outlet during childbirth
- Indications: instrumental delivery, shoulder dystocia, fetal distress, short or rigid perineum
- **Mediolateral (done in QMH) ** vs midline (will go into rectum)
- LA vs epidural
- Complications: pain, infection, gap, bleeding, tear to ana l sphincter, rectum
What are the indications for instrumental assisted vaginal delivery?
- Prolonged second stage
- Fetal distress in the second stage
- Maternal disease (to shorten 2nd stage)
What are the prerequisites for instrumental assisted vaginal delivery?
- Full dilatation of cervix
- Full engagement of the head
- No features of gross cephalopelvic disproportion
- Cooperation of the women
- Good uterine contractions
- Empty bladder
What are the types of ventouse (vacuum) delivery and approach)?
Metal (anterior and posterior): stronger traction force
Soft (silicon rubber) cups: less trauma to the babys head
A well placed cup (in midline over occiput) will result in a well flexed head
What are the basic rules of ventouse delivery?
- Episiotomy
- Negative pressure of 0.8kg/cm2
- controlled two handed manner
- Traction along the pelvic axis (shown in pic below)
- Completed within 15 min of application
- The head should descend with each pull
- The cup should be reapplied no more than twice
Important ddx for this edema?
Subgaleal haematoma
Causes of failed ventouse delivery
- Instrumental failure
- Incorrect position of cup appliciation
- Cephalopelvic disproportion
What are the main 4 types of forceps delivery?
- Outlet forceps (head at bum = easy): Wrigley
- Low forceps (lowest point of babies head is 2cm below the ischial spine = hardest): Simpson
- Rotation from the OP to the OA (seldomly done as it is dangerous): Kielland
- Aftercoming head (breach delivery): Piper
What are the 2 types of fetus face presentation and how does it affect delivery?
Mentus anterior: can do instrumental assisted delivery
Mentus posterior (chin facing rectum): C section
What are the complications of ventous vs forceps?
- Ventouse won’t always require epistiotomy
- Forceps will always require epistiotomy
- However, Ventouse has higher risk
What are the types of hemorrhage that can occur with forceps delivery?
Which is life threatening and why?
Cephalhaematoma = not threatening as confined by the periosteum and skull bone
Subgaleal haematoma = life threatening as collection of blood forms between scalp and periosteum = extends more diffusely across the scalp. Not confined by periosteum so can grow big and cross the midline
SCALP layers = skin, connective tissue, epicranial aponeurosis, loose areolar connective tissue, pericranium
When to choose ventouse or forceps?
- Ventouse preferred: less trauma
- Forceps for when there is fetal distress, cord prolapse, face presentation, preterm, marked active bleeding from a fetal blood sampling site, after coming head of a breech (before 34 wks, must use forceps as Ventouse has risk of ICH)
- Operators choice
What is shoulder dystocia?
What are the complications?
What are the predisposing factors?
When the head is born but the shoulders cannot be delivered by the usual means
Complications: asyphyxia, fractures, brachial plexus injury, or rarely death
Predisposing factors: big baby, small mother, DM, past term, previous history, prolonged 1st/2nd stage, instrumental delivery
What is the sign in shoulder dystocia?
What is management?
Turtle sign: when head presents but is resistant to come out
- McRoberts manouvre (flex mothers hips over belly)
- Generous episiotomy
- Gentle head traction
- Rotate shoulders: suprapubic pressure, Woods manoeuvre
- Deliver the posterior arm
- Gaskin (all-4)
What is approach for term breach delivery?
- Planned vaginal delivery breech delivery is not an option for term delivery
- Can do external cephalic version
- C-section
What are the risks of vaginal breech delivery?
- Fetus (major risks): hypoxia and trauma, cord prolapse, intraventricular hemorrhage, entrapment of the aftercoming head
- Maternal: genital tract trauma, PPH, emergency C/S, anesthesia
What is done for assisted breech delivery?
- Fetal heart rate monitoring
- Generous episiotomy
- Hands off is the best
- Keep the back anterior
- Flexion of neck
- Delivery of the head: Mauriceau-Smellie- Veit manoevre or forceps
How is vaginal twin delivery done?
- Unit equipped for C/S
- Epidural analgesia (increased risk of manipulation)
- Monitoring of fetal heart of both twins
- The 1st twin must present as cephalic (cannot do breech)
After delivery of the 1st twin
* Clamp the cord tightly
* Check the lie of the 2nd twin –> must be longitudinal
* External/internal version if transverse
* Start oxytocin infusion in adequate uterine contractions
* Amniotomy (only perform if presenting part is low in the pelvis to reduce risk of cord prolapse)
* C/S if persistent transverse lie; fetal distress with high presentation
What types of C-sections are there?
What date are they done?
Lower segment (common) vs classical C/S (rare, more complications)
An elective C-section is usually performed at 38-39 weeks of gestation (reduce chance of wet-lung), sometimes it is performed earlier after balancing the risks to mother/fetus against risk of prematurity
What are the types of abd incision in C-section?
Skin cut tells us nothing about uterine incision !!!
What are the types of uterine incision?
Below 2 can do vaginal delivery for next delivery
* Transverse lower segment incision (most common)
* Vertical lower segment incision
Below 3 cannot do vaginal delivery for next delivery (must be repeat C-section) as there is high risk of uterine rupture:
* After transverse lower segment incision, may do J shape extension or T shaped extension if failure to deliver baby initially.
* Classical vertical incision (mid section)
What are the indications for C/S (elective and emergency)?
What are the indications for classical C/S?
- Lower segment poorly formed (preterm: before 28 weeks)
- Lower segment with large vessels (placenta previa) or fibroid or severe adhesions
- Transverse lie with back inferior (if uterine incision is too low, you only have access to baby’s back, which is smooth = nothing to grab, thus we need higher incision)
- Perimortem C/S (woman’s collapsed and you cannot revive mother in 4 minutes = take the baby out and RESUME RESUSCITATION [aim is to save mother]
How is C-section done?
- premedication with antacid to prevent aspiration pneumonia
- Left lateral position
- Catheterize the bladder
- Skin incision: lower transverse (most common) vs midline
- uterine incision: lower transverse (most common, avoids bladder) vs vertical
- Delivery of fetus
- Delivery of placenta
- Closure of uterus, rectus sheath and skin
What are the complications of C-section?
- Short term: hemorrhages, injuries (to bowel, bladder, utereus), infection, anesthesia, Mendelson syndrome (aspiration of gastric contents = chemical pneumonitis [fever, cyanosis, hypoxia, pulmonary edema, potential death]), thromboembolism, wound problems
- Long term: scar rupture, placenta accreta
What are the risks of vaginal birth after caesarean (VBAC)?
Allow vaginal delivery
* Risk of scar rupture (0.5% for lower segment anf 2.2% for classical)
* Emergency C/S (30%)
Repeat C/S: maternal risks but safe to babies
What are the contraindications of vaginal delivery?
- Previous classical C/S, or incision involving upper segment
- Lack of 24 hours facilities for emergency C/S
- Indications for C/S in current pregnancy (e.g. placenta praevia)
What are the relative contraindications of vaginal delivery?
What favors trial of vaginal delivery?
- Extension of uterine incision in previous C/S
- Interpregnancy interval, <6 months
- More than one C/S
Previous vaginal delivery favors trial of vaginal delivery
What is the complication of vaginal birth after caesarean (VBAC)??
Scar rupture: symptomatic (foetal distress, pain, shock)
Complete rupture involves the full thickness of the uterine wall
Incomplete rupture occurs when the visceral peritoneum remains intact
Scar dehiscence: asymptomatic: can be unsuspected and undiagnosed until C/S
Maternal mortality 1%, perinatal mortality 50%
What are the signs of scar rupture for vaginal birth after caesarian?
Abnormal fetal heart pattern, maternal tachycardia, persistent pain, vaginal bleeding, shock, haematuria
Epidural analgesia: not mask the signs of rupture
Uterine tear
Classical
Uterine rupture
Uterus trauma (myomectomy, fibroid)
History of uterine surgery
Entering of uterine cavity
History uterine rupture
