Obstretrics

Question 1

13A07 A 25 year old woman at 28 weeks gestation, with a body mass index (BMI) of45 attends the high risk obstetric clinic. Outline the pathophysiology of morbid obesity affecting pregnancy and describe the implications for obstetric anaesthetic care.

Answer 1

Morbid Obesity and Pregnancy = increased maternal morbidity and mortality Increased

• GDM, Pre-eclampsia Dysfunctional labour (failed IOL, Long second stage, FTP)Caesarean Rate PPH wound infections VTE

1. Airway - decreased MO, neck extension, pharyngeal opening = difficult face mask and intubation.
   
   1. Avoid airway manipulation - neuraxial preferred. Ramp with troop pillow, preO2 >90 before induction or use THRIVE. Use videolaryngoscope, consider 2nd anaesthetist for airway
2. Respiratory - decreased FRC, increased O2 consumption - rapid desaturation . Restrictive Lung disease 2nd increased adipose. Increased rates of OSA
   
   1. ETo2 >90, consider THRIVE. Will need higher airway pressures - aim keep plateau below 30cmH20, PEEP titrated but will need ~10cm, lung recruitment may be needed. Minimise opioids where possible - neuraxial, TAP blocks. Monitoring of birth suite
3. Cardiac - increased CO proportional to obesity. HTN more common - LVH/diastolic dysfunction. RVH 2nd to OSA, Increased arrhythmias 2nd adipose infiltration myocardium. Increased Heart failure - with duration of obesity. Supine Hypotension worse due to increased intraabdominal pressure.
   
   1. ECG . Consider TTE and cardology review depending on Hx and PMH. May need increased monitoring intraoperatively, replace losses with LV dysfunction, Left lateral tilt when supine. Larger BP cuff.
4. GIT - increased risk of hiatus hernia/GORD and increased risk of aspiration.
   
   1. Use prokinetics (Femodipine 20mg) Consider clear fluids in labour. Use cricoid in RSI
5. Endocrine: increase risk of pre pregnancy diabetes and gestational diabetes
   
   1. Monitor BSLs aim 5-10mmol/L, Endocrinology review
6. Haem: Increased VTE risk
   
   1. strict mechanical and chemical prophylaxis
7. Neuraxial: increased spinal/epidural failure, dural puncture rate,
   
   1. Place early epidural before significant contractions, use ultrasound, may need longer needles, for LSCS consider CSE
8. Wound - increased rates of wound breakdown, dehiscence, endometrosis
   
   1. increase Cephazolin dose 3g when >120kg, avoid hypothermia in OT (T>36), Avoid hyperglycaemia BSL<12
9. Drug Dosing - Altered pharmacokinetics
   
   1. Propofol - Lean Body Weight, LMWH - total body weight, suxamethonium TBW
10. Manual Handling - More staff, use hover mats and other devices
11. Vascular access - more difficult, consider Ultrasound, use longer length cannulas to avoid tissuing

Question 2

How would you clincally assess patient complaining of leg numbness the day after a spinal for emLSCS? 70

How would you manage? 30

Answer 2

History

Pre-existing neurological issues

Indication for Emergency LSCS

• prolonged labour, pushing, legs in stirrups

Any coagulation disorder

Spinal - difficulty placing/ attempts. Did they have epidural /CSE

CURRENT Symptoms:

RED FLAGS

• located to particular nerve root
• Motor weakness
• Back pain
• Progressive symptoms
• bowel/bladder incontinence

MANAGE

IF PROGRESSIVE/ RED FLAGS needs MRI lumbar spine

IF NOT

Discussion with Patient - multifactorial and explain all causes

Engage APS review while inpatient and call to follow up patient once home

If hasn’t settled in 4 weeks - organise for MRI Spine and neurology review