Anaesthetic management of pheochromocytoma

1. Dr. Bedhan Chandra Saha
Department of Anaesthesia analgesa & ICU(DA-10th)
Shaheed Ziaur Rahman Medical College , Bogura

2. Pheochromocytoma
 Catecholamine-secreting tumors that arise from
chromaffin cells of the adrenal medulla.
 Secretes excessive amounts of adrenaline and
noradrenaline.
 80% occur unilateral.

3. Pheochromocytoma: “Rule of
10”
 10% extra-adrenal (closer to 15%)
 10% occur in children
 10% familial (closer to 20%)
 10% bilateral or multiple (more if familial)
 10% recur (more if extra-adrenal)
 10% malignant
 10% discovered incidentally

6. Adrenergic Receptors
Alpha-Adrenergic Receptors
α1: vasoconstriction, intestinal relaxation, uterine
contraction, pupillary dilation
α2: ↓ presynaptic NE (clonidine), platelet aggregation,
vasoconstriction, ↓ insulin secretion
Beta-Adrenergic Receptors
β1: ↑ HR/contractility, ↑ lipolysis, ↑ renin secretion
β2: vasodilation, bronchodilation, ↑ glycogenolysis
β3: ↑ lipolysis, ↑ brown fat thermogenesis

7. Signs & Symptoms
The five P’s:
Pressure (HTN) 9%
Pain (Headache) 80%
Perspiration 71%
Palpitation 64%
Pallor 42%
Paroxysms (the sixth P!)
The Classical Triad:
Pain (Headache), Perspiration, Palpitations
Lack of all 3 virtually excluded diagnosis of Pheochromocytoma
Hypertension – commonest presenting complaint
Paroxysmal
episodic

8. Pheo: Hypotension!
 Hypotension (orthostatic/paroxysmal) occurs in
many patients.
 Mechanisms:
ECF contraction
 Loss of postural reflexes due to prolonged catecholamine
stimulation
 Tumor release of adrenomedullin (vasodilatory neuropeptide)

9. Cardiac manifestations
 Sinus tachy, bradycardia , SVT, ventricular ectopics, V tach
 Catecholemine induced inc. myocardial oxygen consumption,
coronary vasospasm
 Angina/MI
 Cardiomyopathy- hypertrophic
 Cardiomyopathy- diastolic dysfn- norepi induced
 Dilated cardiomyopathy- systolic dysfn- epi induced
 CCF with myocarditis
 concentric hypertrophy/ assymetrical hypertrophy
 Rarely sinus node dysfunction

10. Neurologic manifestations
 Hypertensive encephalopathy ( altered mental status,
focal neurological s/s, seizures )
 Stroke – due to cerebral infarction/ embolus
 Intracerebral bleed

11. Diagnosis
 1. Biochemical
 2. Localization

12. 24h Urine Collection
Positive results (> 2-3 fold elevation):
24h Urine catechols > 2-fold elevation
24h Urine total metanephrines > 1.2 ug/d
24h Urine VMA > 3-fold elevation

13. Blood analysis
 Plasma metanephrine levels >220pg/ml
 Plasma normetanephrine levels >400pg/ml
 Plasma catecholamines > 2000 pg/mL
 Clonidine suppression test
 Glucagon stimulation test
 Usually urine analysis is used for screening test and
blood analysis is the confirmatory test.

14. Localization: Imaging
 CT or MRI is the initial localisation test
Sensitivity >95%; specificity >65%
 Metaiodobenzylguanidine (MIBG) scan
 PET (Positron emission tomography) scan

15. Management
 Medical treatment (Symptomatic)
 Surgical management (Definitive)

16. Adrenalectomy is the treatment
 Surgical options :
 ◦ Transabdominal chevron
 ◦ Thoracoabdominal (large, usually right)
 ◦ Flank (11th rib) approach
 ◦ Laparoscopic transperitoneal / retroperitoneal,
if the tumor size is <4-5cm in diameter.

17. Preoperative management
 All patients with a biochemically positive pheochromocytoma
should receive appropriate preoperative medical management
to block the effects of released catecholamines.
 - Main goals:
○ 1) normalize blood pressure, heart rate and functions of other organs
○ 2) restore volume depletion
○ 3) prevent patient from surgery induced catecholamines storms

18. PRE ANESTHETIC
ASSESSMENT
 Verification of history
 Severity of hypertension
 Adequacy of α blockade
 End organ damage
 Cardiology evaluation
 ECG
 CXR
 Echocardiography
 Renal function
 Urea
 Creatinine
 Electrolytes
 Serial hematocrit
 Blood sugar, Calcium

19. Intraoperative Principles
 Administer an anxiolytic
 Place an intra-arterial catheter before induction
 Place an intravenous catheter for antihypertensive
administration
 Place a central venous catheter for intravascular volume
monitoring
 Treat hemodynamic fluctuations with antihypertensives
and adrenergic antagonists
 Monitor for hypotension and hypoglycemia after tumor
isolation

20. Premedication:
 Sedation, anxiolysis, assurance prevent marked
hemodynamic changes intraoperatively.
 Benzodiazepine preferred
 Opioids can provoke CCA release
 Buprenorphine- potent analgesic with anxiolytic & sedative
 properties, cardiovascularly more stable
 Phenoxybenzamine (alpha blocker) should be withdrawn 48
hours prior to surgery, which was most frequently prescribed
for pre operative use.
 Last dose of α adrenergic blocker to be given at night prior to
surgery.

21. Anaesthetic technique
 General anaesthesia
 Regional anaesthesia- mid to low thoracic
 Combined regional and general anaesthesia
 Preferred- combined regional and general anaesthesia
technique
 Here although regional anaesthesia protects against stresses of
surgery,but it cannot prevent catecholamine surges due to tumor
manipulation.

22. Intraoperative management
 Close communication between surgeon and anaesthetist for
success of intraoperative management
 Teamwork between surgeon, anesthesiologist, physician
and endocrinologist.
 Patient to be shifted cautiously
 ECG, pulse oximetry, NIBP/IBP, CVP
 PA catheter mostly not needed
 May be useful in patients with preoperative cardiovascular
compromise or severe LV dysfunction
 Epidural catheter before/after GA at mid (T9-10) or low(T12-
L1) thoracic level

23. Induction
 Should be smooth
 Important for laryngoscopy and tracheal intubation
 2% lignocaine – 1-1.5mg/kg
 Esmolol – 50- 100 µg/kg/min
 During laryngoscopy catecholamine levels ↑
○ Normally- 200- 2000 pg/ml
○ In pheo- 2000- 20,000 pg/ml
 Preoxygenation
 Opioids
○ Morphine/Pethidine: Histamine release
○ Fentanyl: Most commonly used (2-5 µg/kg)
○ Alfentanil/Sufentanil/Remifentanil
 Induction agents
○ Thiopentone : Can cause histamine release
○ Etomidate: Cardiovascularly stable, but, pain on injection
○ Propofol: Logical choice
○ Midazolam: Useful for co-induction

24.  Muscle relaxants
○ Succinylcholine: Sympathetic stimulation, muscle
fasciculation and rise in intra abdominal pressure (should not
use)
○ Vecuronium, Rocuronium, Cisatracurium: Suitable agents
○ Atracurium, Mivacurium: Histamine release
○ Pancuronium: Indirect Sympathomimetic action

25. Monitoring
 ECG
 Pulse oximetry
 Invasive BP
 CVP
 Urine output
 Temperature
 Inspired oxygen conc.
 EtCO2
 PA catheter (+/-)
 Blood sugar

26. Maintenance
 Anesthetic depth more important than agent
○ Halothane/Enflurane- Arrhythmogenic
○ Isoflurane- Commonly used
○ Sevoflurane- Preferred due to rapid titrability of anesthetic depth,
hemodynamics
○ Desflurane- Causes significant sympathetic stimulation
○ N2O- Not contraindicate
 Air/Oxygen mixture,FiO2 0.5,TV 7-10ml/kg,EtCO2 35-38mmHg
 Epidural continuous infusion/repeated boluses with bupivacaine
with/without fentanyl
 Further IV opioids usually not needed

27. Control of Perioperative CCA
Release
 Manipulation of tumor hemodynamic response 
perioperative catecholamine release
 Direct vasodilators
○ Sodium Nitroprusside: Potent arterio-venodilator, rapid onset, brief action,
cyanide toxicity uncommon with small quantity used (Initial 0.5 to
1.5µg/kg/min, mean 3 to 5 µg/kg/min)
○ Nitroglycerine: Mainly affects capacitance vessels, rapid acting, large
doses may be needed
 α adrenergic antagonists
○ Phentolamine: Competitive α1 & weak α2 receptor antagonist, as infusion
or 12 mg boluses, causes tachycardia

28.  β adrenergic antagonists- Help control tachycardia or
tachyarrhythmias
○ Esmolol: Ultrashort acting β1 antagonist. Rapid titrability. Uniquely
suitable.
 Bolus 500µg/kg, infusion 50-200µg/kg/min
○ Metoprolol 1-2 mg boluses
○ Labetalol ( 0.25 mg/kg, upto 20 mg over a period of 10 min)
○ Atenolol (2.5 to 10 mg), propranolol (1 to 10 mg) also used
 Calcium channel blockers- little reduction in preload, less
potential for overshoot hypotension, no rebound hypertension,
less increase in heart rate, absence of cyanide toxicity
○ Nicardipine: Inhibits CCA release from adrenal medullary cells in vitro,
Intra-operative 2.5-7.5µg/kg/min, onset 1 to 5 min, duration 3-6 hours
 Dopa-1 receptor agonist-
○ Fenoldopam: Peripheral vasodilation, ↑Renal blood flow. Undesirable
diuresis

29.  Magnesium sulphate-
○ Inhibits CCA release from adrenal medulla, alters adrenergic
receptor response
○ Loading dose 40-60mg/kg followed by 1-2g/hr continuous
infusion
○ Target blood level 2-4 mmol/L
○ Additional doses necessary during tumour handling
○ Has been used in pregnant patients, patients with CAD

30. Post Resection Hypotension
 After adrenal vein ligation and removal of tumour
 Reasons
○ Suppression of contralateral adrenal gland
○ Downregulation of adrenergic receptors
○ Effect of preoperative adrenoceptor antagonists
○ Sudden increase in venous capacitance
 Mostly amenable to modest fluid load and discontinuation of
vasodilators
 Blood replacement according to losses
 Vasopressor if hypotension unresponsive to fluid
○ Noradrenaline
○ Phenylephrine
○ Dopamine
○ Angiotensin II agonist

31. POST OPERATIVE
MANAGEMENT
 Reversal depends upon preoperative state and intraoperative course
 Neostigmine and Glycopyrrolate. Here, tachycardia associated with
atropine can also occur hypertensive spike
 Shift to ICU/HDU
 Most important post-operative complications
○ Hypertension: Approx. 50% patients
 Recovery from anesthesia
 Pain- Opioids, epidural analgesia, clonidine
 Persistence of high plasma CCA level- restart antihypertensives
 Residual tumour- further evaluation and work up
○ Hypotension:
 Supression of contralateral adrenal
 Downregulation of adrenoceptors
 Persistent effect of preoperative adrenergic blockade
 Intra-abdominal bleed- high index of suspicion

32.  Hypoglycemia
○ Disappearence of pancreatic β cell suppression
○ Lipolysis, glycogenolysis no longer present
○ β-blockers impair recovery, mask symptoms
○ Encephalopathy may occur
○ Frequent monitoring of blood glucose needed
○ Glucose containing IV fluids started after tumour removal

33. SPECIAL
CONSIDERATIONS
 Pheochromocytoma patient for non-pheo surgery
○ Elective surgery to be postponed and elective resection of
pheochromocytoma planned
○ Patients for emergency surgery should be tried to be optimised as far
as possible before surgery
 Pheochromocytoma in pregnancy
○ Misreading of warning symptoms common
○ Maternal mortality 2 to 4% if diagnosed antenatally, 14 to 25% if
diagnosed intrapartum or postnatally
○ Early pregnancy: Medical optimisation for 1to 2 weeks f/b resection
before 24th week
○ Late pregnancy: Medical optimisation till fetus mature, f/b elective
caesarean and resection at same sitting
○ Vaginal delivery preferrably avoided

34. Thanks to all