Category 1 Caesarean with Severe Pre-eclampsia and a Falling Platelet Count
A 31-year-old woman (G2P1) at 35+4 weeks presents with severe pre-eclampsia: blood pressure 176/112 mmHg, persistent headache and visual scotomata, 3+ proteinuria, platelets 82 x 10^9/L (down from 148 two days earlier), AST 212 U/L, ALT 190 U/L, LDH 940 U/L, creatinine 112 micromol/L and urate 480 micromol/L. She has received a 4 g magnesium sulphate loading dose and is on 1 g/h, and a further dose of antihypertensive is due. The CTG shows recurrent late decelerations and the decision is for category 1 caesarean delivery. She weighs 106 kg, is 155 cm tall, has Mallampati III with a short thick neck and facial and tongue oedema, and has one 16-gauge cannula. Coagulation results are pending; fibrinogen was 2.1 g/L six hours ago. The registrar is scrubbed, the neonatal team is present, and the anaesthetist on call is a trainee with consultant support 20 minutes away.
1. Would you choose a neuraxial technique or general anaesthesia? Justify your decision using the platelet count, the HELLP features, the time pressure and the airway, and state what would change your mind.
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My default would be a single-shot spinal anaesthetic, provided a coagulation screen taken now is normal and there is no clinical bleeding - but this is a genuine balancing act, not a textbook answer.
For neuraxial: in pre-eclampsia with normal coagulation, neuraxial anaesthesia is generally considered acceptable at platelet counts above about 70–80 x 10^9/L, and the risk of spinal haematoma with a fine pencil-point needle is extremely low. Against it is general anaesthesia with Mallampati III, a short thick neck, tongue and facial oedema and a 106 kg parturient - a recognisably difficult obstetric airway, where failed intubation is a leading cause of maternal anaesthetic death.
For general anaesthesia: platelets have fallen from 148 to 82 in 48 hours, there are HELLP features (LDH 940, AST/ALT around 190–212) and a fibrinogen of 2.1 g/L six hours ago, all of which predict progression and coagulopathy. Category 1 delivery (within 30 minutes) also limits how long you can wait.
My practical plan: get PT/APTT, fibrinogen and platelets immediately, and TEG or ROTEM if available; give antihypertensive treatment to bring blood pressure below 160/100 mmHg; then perform a 25-gauge pencil-point spinal at L3/4 with hyperbaric bupivacaine 2.2–2.5 mL and fentanyl 15–25 micrograms, and deliberately avoid an epidural catheter because a catheter left in situ while platelets fall creates a removal dilemma.
What would change my mind: platelets below about 75 x 10^9/L or falling further, fibrinogen below 2 g/L, prolonged PT/APTT, active bleeding, or a failed spinal. Then I would proceed to general anaesthesia with a second anaesthetist, the difficult airway trolley and a pre-agreed front-of-neck access plan; waiting for a consultant 20 minutes away is not compatible with a category 1 indication.
2. If a general anaesthetic is required, describe your technique, including how you would control the pressor response to laryngoscopy without harming the fetus, and how you would avoid failed intubation.
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Preparation: sodium citrate 30 mL, ramped 25-degree head-up position, three minutes of preoxygenation to end-tidal oxygen above 0.9 plus nasal apnoeic oxygenation at 15 L/min, second anaesthetist, difficult airway trolley, video laryngoscope, a 6.5 mm cuffed tube, a second-generation supraglottic airway as a rescue, and a pre-agreed front-of-neck access plan. Magnesium infusion is already running - remember it potentiates non-depolarising relaxants and vasodilators.
Induction and airway: rapid sequence with propofol 2–2.5 mg/kg (reduce if there is cardiovascular compromise), alfentanil 10–20 micrograms/kg or remifentanil, and suxamethonium 1–1.5 mg/kg. Blunt the pressor response with lidocaine 1.5 mg/kg, esmolol 0.5–1 mg/kg and an adequate depth of anaesthesia. Avoid ketamine. Intubate with the video laryngoscope at the first attempt; limited attempts, early escalation to a supraglottic airway, and early front-of-neck access if oxygenation fails.
After delivery: give oxytocin as a slow infusion (for example 5 units over 10 minutes) rather than a rapid bolus, because bolus oxytocin causes profound hypotension; avoid ergometrine and carboprost (both raise blood pressure) and use misoprostol for uterine atony. Maintain magnesium and control blood pressure with labetalol or hydralazine.
Fetal considerations: minimise the induction-to-delivery interval, avoid prolonged maternal hypocapnia, keep maternal blood pressure within about 20% of baseline, and warn the neonatal team that the baby has been exposed to opioids and magnesium so they anticipate respiratory depression and hypotonia.
3. What is your postoperative plan, and which complication do you fear most in the first 24 hours?
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Disposition and monitoring: high-dependency or obstetric critical care for at least 24 hours, with continuous ECG, SpO2, hourly blood pressure, urine output, respiratory rate and deep tendon reflexes (magnesium toxicity), and a magnesium level if reflexes are depressed or urine output falls below 30 mL/h. Continue magnesium for 24 hours after delivery. Repeat full blood count, LDH, liver enzymes, creatinine and coagulation at 6 and 12 hours.
What I fear most: pulmonary oedema - a combination of fluid overload, increased capillary permeability, left ventricular dysfunction from hypertension and iatrogenic fluid given during resuscitation. She is already at risk from a creatinine of 112 and a 106 kg weight. I would restrict maintenance fluid to about 80 mL/h, avoid crystalloid boluses unless there is clear hypovolaemia, weigh the patient daily and use strict input/output charts.
Other active surveillance:
- Eclampsia - continue magnesium, keep blood pressure below 150/100 mmHg, minimise stimulation.
- HELLP progression and DIC - falling platelets, rising LDH, bleeding, and a falling fibrinogen; transfuse platelets below 50 x 10^9/L or with bleeding, and activate the massive haemorrhage protocol if needed.
- Epidural or spinal haematoma if neuraxial anaesthesia was used - monitor motor recovery, new back pain and bladder function; urgent MRI if suspected.
- Acute kidney injury, hepatic rupture, abruption, and VTE.
Analgesia: regular paracetamol and a limited opioid, avoid NSAIDs with renal impairment and low platelets, and use a local anaesthetic technique where clotting allows. Give LMWH at least 4 hours after neuraxial puncture, support breastfeeding, and ensure a clear follow-up plan for hypertension at six weeks.