1.33 Severe Hypertension

Question 1

Potential causes for HTN under GA

Answer 1

Anaesthesia:

1. Equipment / Measurement error
2. Inadequate Depth / Awareness
3. Inadequate muscle relaxation
4. Drug error -
   Accidental administration of vasoconstrictor
5. Pain

Patient

1. Raised ICP
2. Thyroid Storm
3. Phaeochromocytoma
4. MH

Surgical
Cross clamping major vessels in Vascular

Question 2

Immediate management

Answer 2

1. Stop Surgery
   ABC
   Call for help
   100% O2
2. Repeat + verify reading
   Ensure cuff size + site appropriate
   No movement artifact
3. If invasive monitoring
   Verify transducer height
   Check cannula for kink / blockage
   Flush system to removal air bubbles (disconnect)

Question 3

management

Answer 3

4. Deflate tourniquet
5. Check ETT position and patency
   Ability ventilate manually
6. Adjust minute volume vent
   correct hypercarbia if present
7. Obtain ABG - asses Paco2
   If high A-a gradient suspect = pulmonary disease
8. Increase volatile agent concentration and FGF deliver
9. TIVA - check cannula site
   flush for line patency -
   consider increasing infusion rates
10. Admin further dose NDMR relaxant if SV

Question 4

MX Drugs

Answer 4

Pain
- further dose opiate / increase Remi

Recheck recent drugs admin
LA w/ Adren

Check notes for drug Hx - ?MAOI interaction w/ ephedrine

Question 5

Suspected raised ICP

Answer 5

11. Suspected raised ICP
check pupil size
response to light
30' head up
aim map >80
normcarb
PaO2 >13
avoid venous obstruction
consider mannitol 0.5mg/kg

Question 6

Antihtn drugs in OT

Answer 6

1. GTN
   2 spray sublingual
   then infusion 1mg/ml titrated to bp
2. MG sulfate
   2-4g bolus over 15min
   1g/hour infusion
3. Hydralazine
   5mg IV bolus
   repeated 15min
4. Labetalol
   5-10mg bolus titrate
5. Consider phentolamine if severe
   1mg bolus
   titrate

Question 7

Secondary management options

Answer 7

Arrange HDU / ICU postoperatively if remain unstable

rule out cardiac ischaemia -
12 lead
trop
echo?

ICP
CTB neurosurgn PRN

Question 8

Thyroid storm?

Answer 8

Thyroid storm
B block
Steroid
Propylthiouracil
suppress thyroid release hormone and conversion

Check post op TFT and refer to endocrine for optimisation

Question 9

If Suspect Phaeo

Answer 9

24h urinary catecholamine

MIBG scan

MRI
Contrast CT
only in blocked patients

Refer to physicians and surgeons specialising in Mx