Recurrent laryngeal nerve palsy (RLNP) and hypoparathyroidism are complications of thyroid surgery. The convalescence can depend on several factors (ie, pain, fatigue, nausea, and vomiting). Supplemental oxygen improves inflammatory and immune function and decreases nausea and vomiting after surgical procedures. We have investigated whether supplemental perioperative oxygen administration could improve surgical outcomes in patients undergoing thyroid surgery.

Three hundred and sixty patients were randomized to an oxygen/air mixture with a fraction of inspired oxygen (FiO₂) of 30% (n = 179) or 80% (n = 181). Administration was commenced after induction of anesthesia and maintained for 6 hours after surgery. The primary end points were temporary or permanent RLNP and transient or definitive hypoparathyroidism. Pain and fatigue scores, nausea, and the number of vomiting episodes were also registered. Preoperatively and at several times during the first 24 postoperative hours, we measured C-reactive protein, interleukin (IL)-6, and IL1β levels.

In the 80% FiO₂ group, the rate of temporary RLNP (4.4%) was significantly lower compared with the 30% FiO₂ group (9.4%) (p = 0.040). In addition, postoperative transient biochemical hypoparathyroidism occurred more frequently in the 30% FiO₂ group (48.5%) than in the 80% FiO₂ group (16.3%) (p = 0.046). Supplemental 80% FiO₂ significantly reduced postoperative levels of C-reactive protein (p < 0.01), IL6 and IL1β (p < 0.05), fatigue (p < 0.01), and overall pain during the first 24 postoperative hours (p < 0.01). Supplemental 80% FiO₂ also reduced nausea and vomiting on the day of operation (p = 0.058).

Supplemental 80% FiO₂ reduced postoperative temporary RLNP and hypoparathyroidism rates and reduced pain, fatigue, nausea, and vomiting after thyroid surgery.