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Anaesthesia for Pituitary Tumour


Lim Wee Leong

Neuroanaesthesia Symposium

Kota Bahru

15th Dec 2012

A short word on where I come from

Centre for Traumatology, Neuro-Spine

and Infectious Diseases

It used to be a


Page • 4

We’re the first hospital in Malaysia to start

collecting money before patients see the doctor.

Operating Schedule in neuro-related surgery

(Two dedicated theatres)

• Monday, Wednesday, Friday: Whole day List

• Tuesday/Thursday: Interventional neuroradiology

• Saturday: Half-day OT (Cranioplasties


• Ortho-spine: Scoliosis, etc

• Emergencies: TBI take the bulk of workload

• We are recognized for Neuroanaesthesia

subspeciality training (3 year programme)


Induction dose 1mg/kg over 20 sec

Follow by 10mg/kg/hr for 10 min , 8mg/kg/hr for 10 min, 6mg/kg/hr thereafter

“10 – 8 – 6 “ Rule


0.5ug/kg/min at induction, 0.25ug/kg/min after tracheal intubation

Then adjust by 0.05ug/kg/min according to haemodynamic status


• Tumours of pituitary gland represents

approximately 10% of diagnosed brain neoplasms

• Transsphenoidal resection of pituitary brain

tumours may account for as much as 20% of all

intracranial operations performed for primary

brain tumours


• Pituitary physiology and pathology

• Different approaches for hypophysectomy

• Perioperative anaesthetic considerations




Anatomy and physiology


• The large anterior lobe or adenohypophysis and

the smaller posterior lobe or neurohypophysis

• The gland averages 6 × 13 × 9 mm3

• Lie within the pituitary fossa or sella turcica

• Bounded by the roof of the sphenoid air sinus

and cavernous sinuses which contain the

carotid arteries and the third, fourth and sixth

cranial nerves

Endocrine glands in the human head and neck and their hormones

Pituitary Gland Pathology

Pituitary GH-secreting Tumours

• Acromegaly in the adult and gigantism before

epiphyseal closure

• Annual incidence of acromegaly is 6-8 cases per


• Insidious in onset, characterized by enlargement of

the jaw, hands and feet and increased soft tissue


• Associated complications of the disease

‣ diabetes mellitus and hypertension

Affected area


Clinical features of acromegaly

Clinical features

Increase in size of skull and supraorbital ridges; enlarged lower jaw;

increase in spacing between teeth/malocclusion

Hands and feet


Soft tissue





Spade-shaped; carpal tunnel syndrome

Macroglossia; thickened pharyngeal and laryngeal soft tissues;

obstructive sleep apnoea

Thick skin; doughlike feel to palm

Vertebral enlargement; osteoporosis; kyphosis

Hypertension; cardiomegaly; impaired left ventricular function

Impaired glucose tolerance; diabetes

Arthropathy; proximal myopathy


• Ischemic heart disease

• Cardiomyopathy

• Congestive heart failure

• Arrhythmias

• Hypertension

Complications of Acromegaly


•Carpal Tunnel syndrome




•(Breast and prostate - uncertain)


• Kyphosis

• Obstructive sleep apnea


• Diabetes mellitus/IGT

• Hyperlipidemia


•Degenerative arthropathy

•Calcific discopathy, pyrophosphate


Cushing’s s Disease

Central Obesity in Cushing’s s Disease

William’s Textbook of Endocrinology. 8 th Ed. Foster, DW, Wilson, JD (Eds), WB Saunders, Philadelphia, 1996

Affected area


Clinical features of Cushing’s

Redistribution of body fat ’moon face’ truncal obesity

or buffalo obesity

Muscloskeletal proximal myopathy, Osteoporosis (increases risk of

fractures during positioning),vertebral collapse.

Soft tissue


Skin fragility with easy bruising (cannulation difficult),

hirsutism ,acne.

Hypernatremia, hypokalemia, alkalosis.

hypertensive; ischemic heart disease and left ventricular


hypertrophy are also common.

Endocrine diabetes

Sleep apnea; Immunosuppression and coexisting


infection, gastroesophageal reflux, renal stones, mental


Airway Management may be problematic

Buffalo Hump


• Prolactinomas are the most frequently observed

type of hyperfunctioning pituitary adenoma

• Represent 20%–30%

of all clinically recognized


• More than 90% of patients respond to medical

therapy with a dopamine agonist such as

bromocriptine and thus few patients present for


Non-Functioning Adenomas

• More likely to be macroadenomas

• Symptoms related to mass effect

Most common :

• Chromophobe adenomas

• Craniopharyngiomas

• Meningiomas



Mass effect


• Low levels of peripheral hormones, not associated with

high pituitary tropic hormones.

• Pituitary apoplexy: : present with sudden headache, loss of

vision, loss of consciousness and panhypopituitarism,

requiring urgent surgery.

• Requires glucocorticoid replacement

• Thyroxine replacement is also required (50–150 ug daily).

• Perioperatively, these patients are extremely sensitive to

anaesthetic agents, , and pressor agents may be needed to

maintain blood pressure.

Surgical Approach

• The pituitary fossa can be approached using the

transsphenoidal, transethmoidal or transcranial


• The transsphenoidal route is preferred for all

except for large tumours

• Transsphenoidal access to the pituitary fossa is

obtained using a sublabial or endonasal approach

Transsphenoidal Approach to the Sella

Turcica for Pituitary Surgery

Positioning for Pituitary Surgery

• Supine

• Head elevated

• Patient closer to the right

hand side of the table

• Neck tilted laterally to

the left, slightly extended

and secured in a mayfield


Surgical Approach

Transsphenoidal Approach


• Decreased diabetes


• Magnified visualization

• Decreased frequency of

blood transfusions

Transcranial Approach


• For pituitary tumors that

have significant suprasellar


• Less surgical stimulation

The Ideal Team for Pituitary tumour surgery

• Neurosurgeon

• ENT Surgeon

• Endocrinologist

• Anaesthetist

• Intensivist

Perioperative Considerations

• Pre-Operative Assessment

• Anaesthetic Management

• Post-operative Considerations

Perioperative considerations

General issues with Anaesthesia for Pituitary surgery

• Optimization of cerebral oxygenation

• Maintenance of hemodynamic stability

• Provision of conditions that facilitate surgical


• Prevention and management of intraoperative


• Rapid, smooth emergence

Common Surgical Problems with Pituitary Surgery

1. Carotid artery injury

2. Central nervous system injury

3. Hemorrhage/swelling of residual tumor

4. Loss of vision / Ophthalmoplegia

5. Cerebrospinal fluid leak

6. Meningitis

7. Nasal septum perforation / Postoperative epistaxis /

Postoperative sinusitis

8. Anterior pituitary insufficiency

9. Diabetes insipidus

10. Death

Complications of Transsphenoidal Surgery

Outcome Measure Incidence (%)


Perioperative Considerations

• Pre-Operative Assessment

Preoperative assessment for pituitary tumours

• General status

• Visual function

• Airway assessment

• Signs and symptoms of raised intracranial pressure

• Endocrine assessment

• Effects of hormonal hypersecretion

• Co-morbidities, particularly in acromegaly or

Cushing’s s syndrome

Cardiac Assessment:

Commonly associated with hyper-secretion from

pituitary acromegaly and Cushing's disease

• Left ventricular hypertrophy

• Coronary artery disease

• Arrhythmias

• Conduction disturbances

• Valvular heart diseases

• Cardiomyopathies

• Congestive heart failure




• Cardiac ECHO

Hormone replacement for patients undergoing

pituitary surgery

• All patients with pituitary disease need endocrine


• Preoperative hormone replacement therapy should

be continued into the operative period

• In general, All patients with Cushing’s s disease

require glucocorticoid cover

Pituitary adenoma for surgery

0800 hours cortisol and short ACTH 1–24 (synacthen)


(cortisol >550 nmol/L)


No Perioperative



Cortisol for 1-3 days

The patient should be given supra-

physiological glucocorticoid cover for 48 h

• Hydrocortisone 50 mg iv 8-hourly on day 0

• 25 mg iv 8-hourly on day 1

• 25 mg iv at 0800 hours on day 2

Cortisol for 3-6 days

Perioperative Considerations

• Anaesthetic Management

Perioperative Considerations

• Anaesthetic Management

Anesthetic techniques

Airway management

Monitoring and intraoperative complications

Emergence and recovery

Anaesthesia Technique

• Both balanced anaesthesia and Total

intravenous anaesthesia (TCI) have been

used with good results

• Choice of anaesthesia depends on

personal preference

• Personal Opinion: No difference

Anesthetic Technique

• Whether an inhalational or intravenous technique is

employed, short-acting agents should be utilised to

facilitate rapid recovery

• Titrate muscle relaxants intra-operatively especially if

patient has h/o skeletal muscle weakness

• Target for post-op extubation

• Postoperative airway maintenance is an issue of


(Prone to subglottic stenosis)

Monitoring and Lines

• At least one large peripheral line (>18G)

• When using TCI, I always use a dedicated venous line

for Propofol/Remifentanil


• I always have intra-art monitoring

• You should have a central line for fluid/electrolyte


• Urine output is a must

• ECG, SpO2, Temperature monitoring

• I tend to use BIS monitoring if using TCI

Airway management

• General Anesthesia with endotracheal

intubation is indicated

• If difficult airway anticipated, then the

intubation technique must include availability

of devices for difficulty airway management

• Throat pack needed for transphenoidal


Airway management

• Reinforced orotracheal tube is recommended

• Positioned in the left corner of the mouth

• Throat pack is then inserted

Prevents bleeding into the glottic region during surgery,

and entry of blood and secretions into the stomach

which may precipitate postoperative vomiting


Over-secretion of the GH causes macroglossia, hypertrophy and thickening

of soft tissues of the oro-pharynx and enlargement of the soft palate,

epiglottis and ari-epiglottic fold.


Anesthesiology, V 93, No 1, Jul 2000

The incidence of difficult laryngoscopy and intubation in acromegalic

patients is higher than in normal patients. . Preoperative Mallampati scores of

3 and 4 were of value in predicting difficult laryngoscopy. Nevertheless,

even this test will miss a significant number of patients with a difficult


Airway Management

• Airway management and tracheal intubation proceed

uneventfully in the majority of patients if large face

masks and long-bladed laryngoscopes are used

• Fibreoptic intubation should be considered in patients

in whom difficult airway management is predicted

(recommended for grades 3 and 4)

• Equipment for emergency tracheostomy should be

available if airway changes are advanced

Four grades of airway involvement

in pituitary acromegaly

Grade 1: No significant involvement

Grade 2 : Nasal and pharyngeal mucosa

hypertrophy but normal cords and glottis

Grade 3 : Glottic involvement including glottic

stenosis or vocal cord paresis

Grade 4 : Combination of grades 2 and 3, i.e. Glottic

narrowing with soft tissue abnormalities

Options for difficult airway management

Why I prefer awake fiberoptic


It is the only technique where I paralyse

the patient only AFTER I secure the airway!

Most other intubation techniques require me to give

my anaesthesia or use of muscle relaxants BEFORE

I secure the airway.

Maintenance of anaesthesia

• short-acting agents are used to allow rapid

recovery at the end of surgery

• During transsphenoidal surgery, ventilation to

normocapnia should be employed. (Excessive

hyperventilation will result in loss of brain bulk and

make any suprasellar extension of the tumour less

accessible from below)

• Longer-acting opioids are administered at the

end of surgery

Perioperative Considerations

• Post-operative Considerations

Emergence from Anaesthesia

• Smooth and rapid emergence from anaesthesia is

essential to allow early neurological assessment

and maintenance of stable respiratory and

cardiovascular variables

• At the completion of surgery, the oropharynx

should also be suctioned meticulously

• Removal of pack

• Avoid coughing as it may dislodge the autologous

fat packing (CSF rhinorrhoea)

Do not forget to

tell your patient

that they have to

breathe from the

mouth after the


In patients with a history of OSA

• Oral airway to facilitate mouth breathing

• A nasopharyngeal airway can also be placed

under direct visualization by the surgeons before

the nose is packed patients prone to upper

airway obstruction may

• Tracheal extubation in a seated position

• Use NSAID’s s instead of opioids for post-op


Post-Operative Analgesia

Post-op analgesia

Small doses of IV Morphine

IV Paracetamol

Non-steroidal anti-inflammatory drugs

Tramadol (less effective and may cause more


Perioperative Considerations

• Disorders of Water Balance

Disorders of Water Balance



Diabetes Insipidus

• Failure of ADH release from the posterior pituitary

• Hallmark of DI is dilute urine in the face of hypertonic


• Aqueous vasopressin (5 units sc every 4h)

• Desmopressin (DDAVP),

A synthetic analogue of ADH

12-to 24-hour duration of action,

Intranasal preparation (5-10 mg qd or bid)

Used both in the ambulatory

and perioperative settings

Differences between Inappropriate Antidiuretic Hormone

(SIADH) and Diabetes Insipidus (DI)

Post-operative Polyuria

I’m going to ask you some questions

The following are features of Cushing’s


• Hypokalaemia

• Osteoporosis

• Hypertension

• Peptic Ulceration

• Muscle Weakness

The following are features of Cushing’s





Peptic Ulceration

Muscle Weakness

Concerning advantages of transphenoidal

approach over transcranial approach:

• Decreased diabetes insipidus.

• Magnified visualization.

• Decreased frequency of blood transfusions

• Less surgical stimulation

Concerning advantages of transphenoidal

approach over transcranial approach:

Decreased diabetes insipidus

Magnified visualization

Decreased frequency of blood transfusions

×Less surgical stimulation

Hypophysectomy will result in

• Depressed Thyroid Function

• Osteoporosis And Generalised Wasting

• The Secretion Of Adrenal Glucocorticoid

And Sex Hormones To A Low Level

• Diabetes Insipidus

• Normal Aldosterone Secretion

Hypophysectomy will result in

Depressed Thyroid Function

×Osteoporosis And Generalised Wasting

The Secretion Of Adrenal Glucocorticoid

And Sex Hormones To A Low Level

Diabetes Insipidus

Normal Aldosterone Secretion

Diabetes inspidus results in

• Hypernatremia

• High plasma osmolarity

• High urine flow

• High urine osmolarity

Diabetes insipidus results in:


High plasma osmolarity

High urine flow

×High urine osmolarity



Pituitary Adenomas

Pituitary adenomas can be classified into:

• Microadenomas (1 cm)

Further classification :

• Non functioning tumours

• Functioning tumours

Functioning Adenomas

• Excess of one or more of the anterior

pituitary hormones

• Prolactinomas followed by GH and ACTH

secreting adenomas

• Adenomas secreting thyrotropin or FSH

and LH are rare

Pituitary Adenomas

Page • 91

Cushing’s s Syndrome vs. Cushing’s s Disease

• Cushing’s s syndrome is a syndrome due to excess

cortisol from pituitary, adrenal or other sources

(exogenous glucocorticoids, ectopic ACTH, etc.)

• Cushing’s s disease is hypercortisolism due to

excess pituitary secretion of ACTH (about 70% of

cases of endogenous Cushing’s s syndrome)

Cushing’s s Syndrome

• Moon facies

• Facial plethora

• Supraclavicular fat pads

• Buffalo hump

• Truncal obesity

• Weight gain

• Purple striae

• Proximal muscle weakness

• Easy bruising

• Hirsutism

• Hypertension

• Osteopenia

• Diabetes mellitus/IGT

• Impaired immune

function/poor wound healing

Multiple Endocrine Neoplasia (MEN) Syndromes

MEN I (Werner)

• Parathyroid hyperplasia

• Pituitary adenoma

• Pancreatic islet cell tumors


• Parathyroid hyperplasia


• Parathyroid hyperplasia

• Medullary thyroid carcinoma

• Pheochromocytoma

• Ganglioneuromatosis

• Marfanoid habitus

• Medullary thyroid carcinoma

• Pheochromocytoma

Different approaches for Pituitary Surgery



• A completely endonasal approach

• A targeted approach

• A more clear visualization - Contact anatomy

• A panoramic view - Angled endoscopes

• A more complete operation leading to a

lower rate of recurrence

Surgical Approach

Transsphenoidal Approach


• CSF leakage and meningitis

• Inability to visualize neural

structures adjacent to large


• Possibility of bleeding from

cavernous sinuses or carotid

Transcranial Approach


• Incidence of permanent

diabetes insipidus and anterior

pituitary insufficiency is


• Damage to the olfactory nerves,

frontal lobe vasculature, and

optic nerves and chiasma

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