Anesthetic overview in Diabetes, thyroid disease, adrenal disease, pituitary disease.

1. Anesthetic considerations for
Endocrine diseases – An overview
R.Srihari

2. Topics for discussion
• Diabetes Mellitus
• Thyroid diseases
• Adrenal cortical diseases
• Adrenal medulla diseases
• Pituitary diseases

3. Diabetes Mellitus
• WHY IS PERIOPERATIVE HYPERGLYCEMIA UNDESIRABLE?
• Dehydration – due to osmotic diuretic effects of glycosuria
• Acidemia- accumulation of lactate and/or ketoacids
• Dyselectrolytemia
• Hyperviscosity with increased thrombogenic complications
• Exacerbation of brain, cardiovascular and renal ischemic
changes
• Impaired immune system response  increased incidence
of postoperative infections
• Impaired consciousness

4. • Standard of blood sugar control
• Assessment of severity of end organ involvement
– Cardiovascular
– Renal
– Retinal
– Autonomic and Peripheral nervous system
• Airway assessment
• Electrolyte and Metabolic derangements
• Acute complications  DKA/
HHNS/Hypoglycemia

5. • Diabetic nephropathy

6. • Retinal hemorrhage

7. • Palm print sign

8. • Prayer sign

10. • Perioperative problems in diabetic patient:
– Surgical induction of stress response with catabolic
hormone secretion  anti insulin effect  insulin
requirements in this period unpredictable
– Interruption of food intake, especially after GI procedures
– Altered consciousness which masks symptoms of
hypoglycemia
– Circulatory disturbances associated with anesthesia and
surgery

11. • Anesthetic management goals:
– To maintain glycemic control
– To avoid further deterioration of pre-existing end
organ damage
– Optimize electrolyte abnormalities prior to surgery
– To shift patient soon on preoperative glycemic control
drugs as soon as possible

12. Thyroid diseases
• Hyperthyroidism
• Hypothyroidism
• Thyroid surgery

13. Hyperthyroidism
• Thyrotoxicosis  state of thyroid hormone
excess
• Hyperthyroidism  state of excess thyroid
gland function

14. Hyperthyroidism
• Ideally, patients should be euthyroid prior to
surgery to avoid precipitating thyroid storm.
• Antithyroid drugs, pharmacologic iodine doses
and beta adrenergic antagonist medications
should be continued through surgery

15. • In an emergent situation, prepare thyrotoxic
patients for surgery in less than 1 hour with
high dose propanolol or esmolol(100-
300mcg/kg/min) titrated till heart rate is less
than 100 beats/min
• Consider generous sedative premedication
unless there is a concern for airway
compromise

16. • Avoid sympathetic stimulation (pain, ketamine,
pancuronium, and local anesthetics with
epinephrine
• Regional anesthesia – beneficial in thytotoxic
patients  blocks sympathetic response
• Thrombocytopenia sometimes occurs in
thyrotoxic patients.
– Consider checking platelet count before initiating
regional anesthesia

17. • Patients may be hypovolemic due to
hypertension, diarrhoea and perspiration
• Hypotension should be treated with direct
acting agents and fluids
• Protect the proptotic eyes which may not
achieve complete lid closure in patients with
Graves disease

18. • Drug metabolism and anesthetic requirements appear
to be increased because of rapid metabolism in
thyrotoxicosis
• However, myasthenia gravis may be seen in some
patients with Graves disease (30% incidence) 
Muscle relaxants must be titrated.
• Large goitres may displace and compress the trachea,
compromising the airway
– Also emergency tracheostomy may be difficult in patients
with goitre

19. Hypothyroidism
• Only severe hypothyroidism requires
postponement of elective surgery
• Securing the airway may be difficult because of
an enlarged tongue, relaxed oropharyngeal
tissues, goitre and poor gastric emptying
• Patients may be prone to hypotension due to
hypovolemia and blunted baroreceptor reflexes
(especially with cardiac depressants and
vasodiators

20. • Patients also manifest carbon di oxide
insensitivity and increased sensitivity to CNS
depressant drugs and paralytic medications
• Corticosteroid supplementation may be
necessary

21. • There is an increased incidence of
– congestive heart failure
– hypothermia
– hypoglycemia
– hyponatremia
– Delayed emergence
• Increased predisposition to myxedema coma
in severe cases

22. Thyroid surgery
• General anesthesia with endotracheal
intubation is the most common anesthetic
technique

23. • Preoperative evaluation should include an
assessment of thyroid function as well as
evaluation for a potentially difficult airway
• Mobility of vocal cords preoperatively is
necessary for documentation

24. • Some surgeons monitor integrity of the recurrent
laryngeal nerve with electromyography (EMG) testing.
– Recording electrodes inserted into laryngeal muscles or
external elctrodes fitted on the endotracheal tube to
detect muscle activity in response to nerve stimulation
– Neuromuscular blockers must be avoided or minimised in
these situations
– Use of LMA?

25. • Postoperative complications of thyroid surgery
– Recurrent laryngeal nerve palsy
– Hypothyroidism
– Hypocalcemia
– Phrenic nerve injury
– Pneumothorax
– Thyroid storm
– Airway obstruction

27. Adrenal Cortical Diseases
• Hyperfunctionality:
– Glucocorticoid excess – Cushing’s syndrome
– Mineralocorticoid excess- Conn’s syndrome

28. • Steroid complications

29. • Anesthetic considerations:
– Patients often exhibit hypertension refractory to
treatment
– Excess intravascular volume can be reduced with
diuretics
• But potassium must be replaced
– Monitor serum glucose levels and correct as
required

30. – Osteoporosis makes careful positioning necessary
– Patients may have unrecognized Coronary artery
disease
– Glucocorticoid cover is mandatory in patients with
Cushing’s syndrome
– Mineralocorticoid cover is necessary post bilateral
adrenalectomy

31. Perioperative steroids

32. • Adrenal Cortical Hypofunction:
– Addision’s disease
– Congenital
– Iatrogenic
• Rifampicin
• Metyrapone
• Ketoconazole

33. • Anesthetic considerations:
– Evaluate and treat volume, hemodynamic, glucose
and electrolyte status as necessary
– Induction agent avoided?
– Patients with adrenal hypofunction exhibit marked
sensitivity to sedatives, anesthetics or vasoactive
drugs  TITRATION IS A MUST

34. • Perioperative steroid coverage is based on
– type of surgery
– Steroid dosage
– Duration of steroid therapy

35. Adrenal Medulla Diseases
• Pheochromocytoma

36. • Anesthetic considerations:
– Optimization of blood pressure prior to surgery is
mandatory
– Preoperative sedation may be helpful

37. – To avoid sympathetic surges or hypotension.
• Why?
• Both scenarios can trigger adrenergic crisis
– Avoid sympathomimetics, vagolytics or histamine
releasing drugs
+
Avoid sympathetic response to induction, intubation,
pneumoperitonium and surgical stimulation

38. – Technique of choice in cases of tumour resection?

39. – Blood pressure should be measured directly.
– Antihypertensive medications should be kept
ready
– Once tumour’s venous supply is ligated, a sudden
decrease in blood pressure may occur.
• Why?
• Due to decrease in the circulating catecholamine levels
and residual alpha and beta blockade

40. – Management post tumour resection?
• Fluid resuscitation
• Vasopressors
– Direct/ Indirect desirable ? Why?
– .
– Phenylephrine, Noradrenaline, Adrenaline
– Vasopressin

41. – Glucose should be monitored perioperatively as
patients may have hyperglycemia preoperatively and
hypoglycemia postoperatively
– Endogenous catecholamine levels should be return to
normal shortly after tumour removal but blood
pressure may take much longer to normalize
– ICU care may be required in the postoperative period

42. – Patients undergoing bilateral adrenalectomy will
require glucocorticoid and mineralocorticoid
replacement therapy

43. Pituitary diseases
• Anterior pituitary hyperfunction
– Pituitary adenoma
• Manifestations:
– Space occupying lesion
– Hormone secreting tumours
» Growth hormone
» Prolactin

47. • Acromegaly:
– Anesthetic considerations:
• Patients should be evaluated for other endocrinopathies and
cardiac diseases preoperatively
• Conventional airway manangement –difficult
• Serum glucose should be monitored
• Muscle relaxants titrated using peripheral nerve stimulator
• Positioning should be done meticulously
• OSA –risk high

48. • Anterior pituitary hypofunction:
– Manifestation :
• Adrenal insufficiency
• Hypothyroidism

49. • Posterior pituitary Gland:
– Diabetes insipidus
– SIADH

50. • Considerations:
– Fluid management
– Electrolyte correction