Preoperative Evaluation and Questions: Indication for surgery? Type of cancer?
Size of goiter or mass? Tracheal compression or deviation (CXR)? Airway compromise?
Is patient euthydoid? Check thyroid labs, eval heart rate, pulse pressure, and reflexes.
Risk: Mortality: <0.5%
Hematoma post-op 1-2%
Laryngeal nerve injury 0.4-0.8%
Thyroid Storm – Extremely rare, usually occurs in hyperthyroid patients with Graves disease. Signs include hyperthermia, tachycardia, altered mental status, and rhabdomyolysis.
[Jaffe RA: Anesthesiologist’s Manual of Surgical Procedures, 4th ed. LWW: Baltimore, 2009]
Induction/Airway: Patients with hypothyroidism can experience severe hypotension on induction. Potentially difficult intubation due to large goiter or mass compressing or distorting airway anatomy. Can use standard ETT but secure it in a way that does not encroach on surgical field.
Lines and Monitors: Standard ASA. Arms will be tucked and surgeons may lean on NIPB arm cuff. Consider radial A-line or NIBP cuff on leg.
Mode of anesthesia: General Anesthesia. Hypothyroidism causes increased sensitivity to anesthetics and neuromuscular blockers.
Positioning: Supine with shoulder roll to extend the neck. Place goggles because surgeons will be working near patient’s eyes.
Surgical Course: Some surgeons request maximum neuromuscular blockade to facilitate exposure. Trachea and laryngeal nerves are at risk during dissection. Closure is fairly quick and NMB reversal may be problematic if surgeon has insisted on excessive relaxation.
Intraoperative Goals and Events:
Monitor tube placement and connections. Surgeons will be in close proximity to ETT and may cause dislodgement or disconnection. Be prepared to rapidly re-establish the airway if necessary. Surgeons may send tissue for frozen section to verify thyroid vs parathyroid tissue.
EBL: less than 100ml
Duration: 1 -2 hrs
Emergence: Gradual extubation to avoid coughing or straining. Monitor closely for signs of laryngeal nerve or tracheal damage.
Post-Operative Concerns, Transport, Disposition: PACU. Monitor serial Ca levels for hypocalcemia post-op from unintended Parathyroidectomy.