Adrenalectomy

Airway: ETT
Access: 14G IV x2. Pain: Consider epidural if open.
Position: Variable, but most commonly lateral
Time: 1-2 hours
Blood loss: May be substantial with right adrenal tumours due to IVC proximity
Special: Preoperative diagnosis critical to preparation. Labile BP with manipulation of adrenal gland

Removal of the adrenal glands can be performed:

Considerations

  • Preoperative diagnosis
    Significantly affects pre-operative management.
    • Aldosteronoma
    • Phaeochromocytoma
      Ensure adequate control of haemodynamic state prior.
    • Cortisol-producing tumour
    • Non-functioning lesion
    • Metastasis
    • Adrenocortical carcinoma

Preparation

  • Standard ANZCA monitoring
  • Epidural awake
    If being used.
  • Arterial line
    Femoral preferred for better monitoring of central pressures.
  • CVC
    If any possibility of requiring adrenaline/noradrenaline.
  • PAC/
    Consider for phaeochromocytoma with impaired cardiac function.

Induction

  • Gentle IV induction with paralysis
    Consider intubation with 3-5μg/kg fentanyl and 50mg/kg MgSO4, followed by MgSO4 infusion at 1-2g/hr.
  • Ensure adequate depth prior to stimulation

Intraoperative

  • Volatile/opioid/relaxant
  • Consider continuous epidural infusion

Control of hypertension:

  • Ask surgeon to cease manipulating adrenal gland
  • Phentolamine 1-2mg IV, up to 5mg boluses
    Reversible non-selective α-antagonist. Short duration of action; may demonstrate tachyphylaxis.
    • Can be used as a sole agent
    • Useful to control BP surges
      Behaviours similar to reverse metaraminol.
    • Can be used by infusion at 0.5-1mg/min
  • Labetalol 5-20mg IV
    Combined α- & β-antagonist.
  • SNP 0.5-1.5μg/kg/min, up to 4μg/kg/min
  • GTN 0.5-10μg/kg/min
  • MgSO4 1-2g IV
  • Nicardipine
    If in America.

Control of arrhythmia:

  • Esmolol 0.5mg IV, with infusion at 50μg/kg/min
    For reflex tachycardia.
  • Amiodarone
    For ectopy.

Control of hypotension:

  • Occurs in 20-70%
    Particularly post tumour ligation.
  • Stop infusions
  • Fluid load
  • Commence noradrenaline
  • Consider vasopressin
    • 0.4-20 units
    • Infusion to follow

Surgical Stages

  • Incision may be excessively stimulating
  • Insufflation may cause hypertension
    Tumour compression, altered tumour blood flow, sympathetic response to hypercapnoea.
  • Ensure good control of blood pressure prior to tumour handling
  • Manipulation of the adrenal gland may cause catecholamine release
    Significant hypertension and dysrhythmia may occur.
  • Following clamping of vein and removal of adrenal gland, significant hypotension occurs
    Anticipate:
    • Fluid load
    • Adrenaline infusion for ↓ CO
    • Vasopressin/noradrenaline if ↓ MAP with normal or ↑ CO
      Vasopressin is useful for treating catecholamine-resistant hypotension.
    • Often more difficult to manage than the hypertension prior
      Have vasopressors prepared.

Emergence

  • Extubation dependent on haemodynamic stability

Postoperative

Key considerations:

  • B
    • May required post-operative ventilation
  • C
    • Invasive monitoring
      Require at least 24 hours of HDU monitoring post-operatively.
    • Haemodynamic instability
      • Risk factors
        • High plasma noradrenaline levels
        • Large tumour size
        • Large postural drop
        • Pre-induction MAP >100mmHg
      • Hypotension
        May have ongoing vasopressor/inotrope requirements.
      • Hypertension
        • Acute hypertension usually due to pain, pre-existing essential hypertension, urinary retention, or volume overload
        • Persistent post-operative hypertension may indicate incomplete resection
  • D
    • Return to normal insulin sensitivity
      Hypoglycaemia can occur from relative insulin excess; monitor Q2H.
  • E2
    • Hypoadrenocorticism
      • Usually only occurs if bilateral resection
      • Requires gluco/mineralocorticoid replacement
        Commence hydrocortisone 100mg Q8H, weaning to 25mg BD over first 72/24 post-op; and then usually conveted to prednisolone.

References

  1. Connor D, Boumphrey S. Perioperative care of phaeochromocytoma. BJA Educ. 2016 May 1;16(5):153–8.