1. Anaesthetic management of pheochromocytoma
Dr. S. Parthasarathy
MD., DA., DNB, MD (Acu),
Dip. Diab.DCA, Dip. Software statistics- Phd
Mahatma Gandhi Medical college and research institute , puducherry , India

2. What is it ??
Pheochromocytoma is a rare catecholamine secreting tumor arising commonly from adrenal medulla and to some extent from other paraganglia of the sympathetic chain but can arise from any part of the body
Intra adrenal – pheo ( WHO – 2004)
Others – extra adrenal paragangliomas
with an incidence of per million population per year.

3. Why is it so called ?? Pheo --- dusk Chromo – colored Cytoma -- tumour
Roux and Mayo performed succesful surgery in 1926
Still we are discussing

4. the “rule of 10” 10% of the tumors are bilateral,
10% are extra-adrenal,
10% of the tumors undergo malignant change 10% of the patients, pheochromocytoma exist with various familial disorders such as multiple endocrine neoplasia (MEN) syndromes [MEN 2A and 2B], von Recklinghausen disease, and von Hippel Landau syndrome.

5. MEN type IIA or IIB.
Type IIA includes medullary carcinoma of the thyroid, parathyroid hyperplasia, and pheochromocytoma;
Type IIB consists of medullary carcinoma of the thyroid, pheochromocytoma, and neuromas of the oral mucosa.
Pheochromocytomas may also arise in association with von Recklinghausen neurofibromatosis or von Hippel- Lindau disease (retinal and cerebellar angiomatosis

7. Clinical features

8. Urine

9. Systolic blood pressure changes – fluctuations present
Epinephrine
More consistent high BP – norepinephrine

10. Subtle signs
Paroxysmal hypertension associated with a normal blood pressure between crises occurs in 50% of patients.
30% of patients will have sustained hypertension.
Twenty-four–hour ambulatory blood pressure monitoring.
Orthostatic hypotension is also a common finding and considered to be secondary to hypovolemia and impaired venous and arterial vasoconstrictor reflex responses.

11. Feeling of doom
“ I thought I was going to die “
Mimicking
Pregnancy ?? Toxemia

12. Adult pheochromocytomas are solid, highly vascular tumors usually 3 to 5 cm in diameter and average 100 g in weight (range, 1.0–4000 g). The average-size adult pheochromocytoma contains 100 to 800 mg of norepinephrine.
Rt adrenal more common

13. How to diagnose ?? Secretions Degradation products
Intratumour degradation !!
Imaging

14. Adrenal CT and MRI have comparable
sensitivity and specificity.
Metaiodobenzylguanidine (MIBG) scanning offers superior specificity to MRI and CT, and is particularly helpful in localizing extra adrenal masses

15. MRI imaging

16. May be interfered by drugs ?? Paroxysms
Normal plasma level of catecholamines…
- free epinephrine= 30 pg/ml (0.16 n mol/L)
- free norepinephrine= [200 – 1700 mcg/ml] 300 pg/ml (1.8 n mol/L)
- free dopamine= [<30 mcg/ml] 35 pg/ml (0.23 n mol/L)
T 1/2 ~ 2 minutes
Plasma Metanephrines
May be interfered by drugs ?? Paroxysms

17. Plasma free normetanephrine greater than 400 pg/mL and/or metanephrine greater than 220 pg/mL is diagnostic of a pheochromocytoma.
If normetanephrine is 112 to 400 pg/mL or metanephrine is 61 to 220 pg/mL, the diagnosis is equivocal.
A pheochromocytoma is excluded if normetanephrine is less than 112 pg/mL and metanephrine is less than 61 pg/mL.

18. 24 hour urine… - Normetanephrine = 50 – 840 mcg/ml - Metanephrine = 0 – 370 mcg/ml - Vanillylmandelic acid (VMA) = <7.2 mcg/ml - Norepinephrine = 13 – 107 mcg/ml - Epinephrine = 0 – 15 mcg/ml

19. Clonidine suppression
50 % suppression will not be there
Glucagon stimulation test
–increase plasma catecholamine but bp better with Pre admin with nifidepine

20. Hyperglycemia
Hypercholesterolemia
Hyperenninemia
Hypercalcemia
Steroids
Glucagon
Anaemia or polycythemia
ECG
ECHO
Chest Xray

21. Preoperative preparation
Rate
Blood pressure
Arrhythmias
End organ damage
WHY ??

22. The treatment is only surgical

23. Induction without preparation may be hazardous
The perioperative mortality associated with phaeochromocytoma is around 2% - unprepared may go upto 50 %
Induction without preparation may be hazardous
Venodilation and

24. catastrophy

25. Alpha blockers Phenoxybenzamine oral phenoxybenzamine 20 mg tds
with a maximum dose of 250 mg.
a long duration of alpha blockade and non-competitive blockade as a result of covalent binding to drug receptors prevents the frequent surges of catecholamine releases during pre-op period.
it blocks alpha-2 receptors also thereby inhibiting the feedback loop for release of nor-epinephrine and as a result huge amount of nor- epinephrine is released causing undesirable chronotropic and inotropic effects

26. Phenoxybenzamine
Increased post-op somnolence, headache, stuffy nose, and postural hypotension are some of the major side effects of phenoxybenzamine.
Insensitive to postop agonists
Can result in excess fluid administration and edema.
Tachycardia – beta blockers to be added – aten, metoprolol

27. So what do we need ??
Prazosin 1 mg tds upto 12 mg/ day – selective alpha 1 blocker
Doxazocin 2 – 4 mg/ day – long life
May not need beta blockers
Terazocin – similar but shorter half life
Proved doxazocin + labetolol 100 mg / day – effective

28. Do we need beta blockers ??
Symptom free
Rate
Arrhythmias
Epinephrine and dopamine secreting tumours
Beta blockers only after sufficient arteriolar dilation – 2 weeks of Alpha blockers

29. Atenolol 100 mg/ day
Bisoprolol 10 – 20 mg / day
Labetolol 100 mg – 400 mg / day
Carvidolol mg
But propronolol – COPD and PAD
Celiprolol – newer – 200 mg / day – beta 1 antagonist but beta 2 agonist

30. Other drugs
SNP
0.5–1.5 µg/kg/min initially, increased to maximum of 8 µg/kg/min; titrate to effect.
Powerful vasodilator; short acting.
Nicardipine 1–2 µg/kg/min increased to 7.5 µg/kg/min;
titrate to effect.
Octreotide
magsulf

32. Adequate control achieved ??
BP 160/ 90 or less
Mild orthostatic hypotension > 80/45
No arrhythmias
ECG should be free of ST-T changes
Nasal congestion
Roizen’s criteria

33. Anaesthesia

34. Goals
Intraoperative goals include avoiding drugs or maneuvers that may provoke catecholamine release or potentiate catecholamine actions and maintaining cardiovascular stability, preferably with short-acting drugs.

35. Intra op problems hypertension and/or arrhythmias
anesthetic induction,
intubation, surgical incision,
abdominal exploration and particularly during tumor manipulation,
secondary to hypotension following ligation of the tumor’s venous drainage.

36. Talk with the surgeon

37. During laparoscopic surgery, creation of the pneumoperitoneum may cause release of catecholamines and large changes in hemodynamics that can be controlled with a vasodilator
Acute pulmonary edema can complicate the picture
Shorter post op stay !!!

38. Monitors Routine + CVP –
pressure change of more than 10 with IPPV- hypovolumia
Arterial catheter
PAC when dysfunction
Urinary output
TEE
Depth
Glucose , electrolytes

39. Iv fluids
RL or physiologic saline are the recommended fluids for use prior to tumor removal and a dextrose-containing solution should be added after tumor removal.
A large positive fluid balance is usually required to keep intravascular volumes within a normal range.

40. Anaesthetic concerns – technique does not matter
Prevent catecholamine surge
Decrease ANS involvement

41. Factors that stimulate catecholamine release such as fear, stress, pain, shivering, hypoxia, and hypercarbia must be minimized or avoided in the perioperative period.
GA or RA + GA – OK
Midthoracic epidural with GA
Can epidural block surges ??

42. Anesthetic drugs that appear safe include thiopental, etomidate, benzodiazepines, fentanyl, sufentanil, alfentanil, enflurane, isoflurane, nitrous oxide, vecuronium, and rocuronium.
Despite these recommendations, the choice of anesthetic is not as crucial as the understanding with which the agents are used.

43. Say no to drugs !!
Scoline
Atracurium
Morphine
Ephedrine
Metoclopramide
Ketamine
Desflurane . Halothane

44. Intra op hypertension Usually surges of 200 mmHg SNP Phentolamine
Labetolol
dexmed
Isoflurane
Epidural

45. Intra op arrythmias
Lignocaine
Esmolol

46. Blood loss ??
No blood salvage
Inotropes ready – phenylephrine – better for hypo if volume status corrected
Vasopressin after clamps – better if down regulation suspected
Antiemetics – droperidol mg IV with dexa

47. Postoperative Management
Patients usually remain in the ICU for at least 24 hours. Adequate pain control is essential, although somnolence and an increased sensitivity to narcotic analgesics have been observed.
The need for controlled ventilation is dictated by the extent of surgery, the site of surgery, and the patient’s medical condition.

48. There are two adrenals !!!

49. The majority of patients become normotensive following complete tumor resection.
Plasma catecholamine levels do not return to normal until 7 to 10 days after surgery due to a slow release of stored catecholamines from peripheral nerves.
Fifty percent of patients are hypertensive for several days following surgery,
25% to 30% of patients remain hypertensive indefinitely
Post op hypoglycemia ??

50. Is there a renal ischemia ??
Hypertension post op ??
Is there a metastasis ??
Is it incomplete ??
Is there a renal ischemia ??
Steroid supplementation is necessary for patients who had bilateral adrenalectomies or if hypoadrenalism is suspected.

51. In emergencies – not a known case
Suspect pheo
Vasodilators
Postpone surgery
Investigate and optimize

52. Summary
Diagnosis
Investigations
Preop
Intra op
Post op

53. Now-- what is the role of postgraduates?