الفهرس 
ANAESTHETIC MANAGEMENT OF PITUITARY GLAND EMERGENCIES
Anatomy of pituitary glandOnly 14 pages are availabe for public view
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Abstract
Endocrine emergencies are one of most important
challenges in anaesthetic practice. They include:
Pituitary apoplexy:
Haemorrhage or infarction of pituitary gland mostly
pituitary adenomas causing suppression of hormones secretion
leading to hormonal deficiencies. The immediate medical
management should include careful assessment of the patient’s
haemodynamic status and commencement of intravenous (IV)
fluids and steroid therapy.
Thyrotoxic crisis:
Acute increase in T3 and T4 in blood causing hypertention,
tachydysrhythmia and fever. Management includes cooling the
patient, administration of Propylthiouracil, imidazoles and β-
blockers. Good preoperative preparation of the patient to be in the
euthyroid state can decrease the incidence of thyroid storm.
Intraoperatively, it is advised to prevent stress response to
intubation, and cautiously use drugs with sympathomimetic
activity.
Myxoedema coma: Deficiency of T3 and T4 is manifested by bradycardia,
hypotension, decreased tolerance to cold weather, disturbed
conscious level. Anaesthetist should investigate any suspected
patient to have hypothyroidism. Postpone any elective surgery till
euthyroid state. Emergency surgeries are done after administration
of thyroxine. Regarding sedatives and analgesics, there
requirements are decreased.
Diabetic ketoacidosis (DKA):
Characterized by hyperglycaemia, ketosis and acidosis. It is
manifested by polyuria, polydipsia, dehydration, Kussmaul
breathing with acetone odour and disturbance of consciousness up
to coma.
Management include fluid replacement, insulin therapy
with care to potassium monitoring. Strict monitoring of blood
glucose, electrolytes and blood gases is required.
Hyperglycaemic hyperosmolar state:
Characterized by hyperglycaemia, hyperosmolarity but
without keto-acedosis. Management depends mainly on fluid
replacement. However, if the patient’s serum glucose does not
decrease by 50–70 mg/dl per hour despite appropriate fluid
management, a bolus of IV regular insulin may be given. Hypoglycaemia
Decreased blood glucose level below normal range is
usually due to over dose of insulin or oral hypoglycaemic drugs.
Patients present with sweating, fatigue, confusion, behavioural
changes, seizures and coma. Signs include pallor, tachycardia,
hypertension and hypothermia. Management by glucose
administration orally if conscious or intravenous if comatosed.
The general principle for preoperative preparation is to
maintain patient euglycaemic as much as possible as this will decrease
complications. It can be achieved by strict monitoring of blood
glucose, and insulin therapy using Variable rate intravenous insulin
infusion, the Alberti GIK regimen or intravenous insulin sliding scale.
Also good anaesthetic management by measures that decrease stress
and good analgesia will also maintain patient euglycaemic.
Acute adrenal insufficiency
The hallmark of acute adrenal insufficiency is hypotension
and shock refractory to fluid resuscitation and vasopressors. Acute
management is based on administration of IV hydrocortisone,
detection and treatment of hypoglycaemia, and identification and
treatment of precipitating causes. The key to prevent it is to ensure
adequate steroid replacement therapy for patients with adrenal
insufficiency during the perioperative period. Steroid replacement
depends mainly on the type of surgery. Phaeochromocytoma :
Occurs as result of excess catecholamines secretion, mainly
from adrenal medulla tumours. It manifests by severe attacks of
hypertention and tachydysrhythmias which may be fatal.
Preoperative preparation includes α blocking drugs as
phenoxybenzamine. Intraoperative close monitoring is mandatory,
especially invasive blood pressure monitoring. Controlling attacks
of hypertension by the use of hypotensive agents like prazocin,
sodium nitroprusside, calcium channel blockers and magnesium
sulphate. β blockers are used only after α blockers.
Carcinoid Crisis:
Carcinoid crisis is manifested by profound flushing,
diarrhoea, haemodynamic instability (hypotension and rarely
hypertension), bronchospasm, tachycardia, and mental
abnormalities from light-headedness to coma. Management
include administration of octreotide. It is contraindicated to use of
β2 adrenergic agonists for the treatment of severe bronchospasm,
or to use of indirect adrenergic agonist (e.g., ephedrine) in
managing hypotension because they worsen the mediator cascade.
Drugs increasing histamine release as morphine and atracurium
are better to be avoided.