Labour (Umbilical cord prolapse; perineal tears; c-section) Flashcards
Describe what is meant by umbilical cord prolapse [1]
Cord prolapse is when the umbilical cord descends below the presenting part of the fetus and through the cervix into the vagina, after rupture of the fetal membranes; or can occur or occultly, where it lies alongside or just ahead of the presenting part within intact membranes.
Explain the adverse effects of umbilical cord prolapse [2]
Fetal hypoxia occurs via two main mechanisms:
* Occlusion – the presenting part of the fetus presses onto the umbilical cord, occluding blood flow to the fetus.
- Arterial vasospasm – the exposure of the umbilical cord to the cold atmosphere results in umbilical arterial vasospasm, reducing blood flow to the fetus.
What is the most significant risk factor for umbililcal cord prolapse? [1]
Name two more [2]
when the fetus is in an abnormal lie after 37 weeks gestation (i.e. unstable, transverse or oblique).
- provides space for the cord to prolapse below the presenting part
Breech presentation – in a footling breech, the cord can easily slip between and past the fetal feet and into the pelvis.
Polyhydramnios – excessive amniotic fluid around the fetus
How do you manage an umbilical cord prolapse? [1]
1. Manually elevate the presenting part by lifting the presenting part off the cord by vaginal digital examination. Alternatively, if in the community, fill the maternal bladder with 500ml of normal saline (warmed if possible) via a urinary catheter and arrange immediate hospital transfer
2. Encourage into left lateral position with head down and pillow placed under left hip OR knee-chest position. This will relieve pressure off the cord from the presenting part. OR the patient is asked to go on ‘all fours’ until preparations for an immediate caesarian section have been carried out
3. retrofilling the bladder with 500-700ml of saline may be helpful as it gently elevates the presenting part
4. Consider tocolysis (e.g. terbutaline) – if delivery is not imminently available this will relax the uterus and stop contractions, relieving pressure off the cord.
5. Delivery is usually via emergency Caesarean section
Describe the four degrees of perineal tear [4]
Describe the level of care needed to fix them [4]
The RCOG has produced guidelines suggesting the following classification of perineal tears:
first degree
* superficial damage with no muscle involvement
* do not require any repair
second degree
* injury to the perineal muscle, but NOT involving the anal sphincter
* require suturing on the ward by a suitably experienced midwife or clinician
third degree:
* injury to perineum involving the anal sphincter complex (external anal sphincter, EAS and internal anal sphincter, IAS)
* 3a: less than 50% of EAS thickness torn
* 3b: more than 50% of EAS thickness torn
* 3c: IAS torn
* require repair in theatre by a suitably trained clinician
fourth degree
* injury to perineum involving the anal sphincter complex (EAS and IAS) and rectal mucosa
* require repair in theatre by a suitably trained clinician
Describe how you manage the tears [4]
- Broad-spectrum antibiotics to reduce the risk of infection
- Laxatives to reduce the risk of constipation and wound dehiscence
- Physiotherapy to reduce the risk and severity of incontinence
- Followup to monitor for longstanding complications
What is the clinical significance of a 3rd or 4th degree tear with regards to future pregnancies? [1]
Women that are symptomatic after third or fourth-degree tears are offered an elective caesarean section in subsequent pregnancies.
Describe a method for reducing the risk of perineal tears [1]
Perineal massage is a method for reducing the risk of perineal tears. It involves massaging the skin and tissues between the vagina and anus (perineum). This is done in a structured way from 34 weeks onwards to stretch and prepare the tissues for delivery.
What are the two different types of c-section? [2]
- lower segment caesarean section: now comprises 99% of cases
- classic caesarean section: longitudinal incision in the upper segment of the uterus
NOTE: You may hear doctors refer to Mendelson Syndrome- What is this? [1]
it is an eponymous name for chemical pneumonitis secondary to aspiration of stomach contents during general anaesthesia. It is more common in pregnant women.
How can you reduce this risk of aspiration pneumonitis during c-sections? [1]
PPIs / H2 receptor antagonists should be offered prior to GA to reduce the risk of aspiration pneumonitis.
What are indications for an elective caesarean? [+]
- Previous caesarean
- Symptomatic after a previous significant perineal tear
- Placenta praevia
- Vasa praevia
- Breech presentation
- Multiple pregnancy
- Uncontrolled HIV infection
- Cervical cancer
An elective c-section is usually performed under which type of anaesthetic [1] and at how many weeks? [1]
Usually these are performed after 39 weeks gestation; use spinal anaesthetic
What are the 4 categories of emergency c-section? [4]
Category 1:
- There is an immediate threat to the life of the mother or baby.
- Decision to delivery time is 30 minutes.
Category 2:
- There is not an imminent threat to life, but caesarean is required urgently due to compromise of the mother or baby.
- Decision to delivery time is 75 minutes.
Category 3:
- Delivery is required, but mother and baby are stable.
Category 4:
This is an elective caesarean
The most commonly used skin incision is a transverse lower uterine segment incision. There are which two possible incisions? [2]
Pfannenstiel incision is a curved incision two fingers width above the pubic symphysis
Joel-cohen incision is a straight incision that is slightly higher (this is the recommended incision)
