1.28 Pheochromocytoma

Question 1

Outline preoperative pharmacological management

Answer 1

Alpha Blockers + Beta Blockers

Question 2

Alpha blockers - use + aims

Answer 2

Used for periop reduction of 
1 BP
2 Incidence of hypertensive crisis 
(induction + Tumour manipulation)
3 Myocardial Dysfunction

Increase intravascular volume

Stimulate resensitization of adrenergic receptors

Perioperative Aims
1 BP <160/90
2 Orthostatic hypotension (>80/45)
3 Ischaemic free ECG (max 1 PVC per 5min)
4 Nasal congestion

Question 3

Alpha blockers types

Answer 3

Non selective
1) Phenoxybenzamine 10mg bd (max 250mg/day)
- started 2-4/52 prior
Disadvantage
a1 blockade
tachycardia + postop refractory hypotension

Selective

A1 blockers
Doxazocin / prazosin
avoid tachycardias - less effective preventive HTN crises

Question 4

Beta Blockers

Answer 4

Use

Counteract tachycardias
(d/t a blockers or catecholamine XS)

Prescribed AFTER alpha blockade
avoids unopposed B2 blockade
and resulting vasoconstriction

Increase risk failure in patients w/ dysfxn:
increase afterload w/ poor contractility

Question 5

Beta bockers types

Answer 5

Selective B1
Atenolol / Bisop
COPD / PVD patients

Non selective
Propranolol / labetalol

Question 6

Anaesthetic techniques reduce CVs instability during procedure

Answer 6

Aim Maintain CVS stability
minimise surges during crucial points
- Induction + intubation / Incision tumour manipulation post tumour ligation and removal

1. Consider premed to reduce stress / anxiety
2. Use drugs to obtund laryngoscopy pressor response
   Remi / Fentanyl
3. Ensure adequate depth prior to
4. Care with histamine release drugs
   trac / morphine
5. Invasive monitoring _ CVP
   allows accurate and quick monitoring CV status
   ?TOE if severe dysfxn

Question 7

Anaesthetic techniques cont

Answer 7

6. Thoracic epidural
   - periop analgesia + sympathetic blockade

7/ acoid stimuating catecholamine rlease from
hypoxia
hypercarbia
pain 
inadequate muscle relaxation
extremes of temrperature

Intraop anti HTN for controling surges

Question 8

Intraop anti HTN for controling surges

Answer 8

Nitrates
GTN/SNP

Phentolamine
Vasodilator + alpha blocker

Magnesium sulphate

CCB
nicardipine

Beta blockers
esmolol and labetaolol

Question 9

Anaesthetic mx

Answer 9

Beware of multifactorial hypotension post tumour ligation + removal
requires fluid loading prior to ligation
+/- vasopressors / inotropes

phenylephrine /norad etc

Post op
severe comorbs or periop instability
Transfer to HDU / ICU 
optimise CV status
fluid balance
DO2
Glycaemic control (hypoglycaemia prob)
Analgesia