hemithyroidectomy as a outpatient procedure is performed in some countries, it has never been done a RCT whether it is feasible

Many surgical procedures, which previously resulted in days to week's hospital admissions, are now done as outpatient procedures. This is the result of better surgical and anaesthesiology techniques as well as the economic incentive.

Examples from another surgical fields are cholecystectomy and further back in oto-rhino- laryngology (ORL) also tonsillectomy.

Hemithyriodectomy as an outpatient procedure is becoming increasingly popular and is already applied in some countries. However many European countries is continuing the procedure with hospital admission post-operatively (inpatient surgery), due to risk of complications. In Denmark hemithyroidectomy is currently done with at least one night hospital admission for observation of above mentioned . At the ORL department at Køge hospital it is annually performed approximately 200 hemithyroidectomies. It is a common procedure and the number of procedures yearly is increasing. Complications to hemithyroidectomy include postoperative haemorrhage, damage to the recurrent laryngeal nerve, hypothyroidism and infection and veryn rarely hypocalcaemia. With sufficient patient information, the above-mentioned complications can be managed in an outpatient setting. Postoperative haemorrhage is the most serious complication and thyroid surgery is unique in outpatient setting, considering the risk of cervical haemorrhage which secondary can lead to respiratory failure due to tracheal compression and laryngeal oedema in a rapid sequence. Incidence of haemorrhage after thyroid surgery varies from 0.19 % to 2.8 % of which most bleedings occur within six hours postoperatively. There are two different approaches in the event of post- operative haemorrhage; acute decompression bedside and acute re-operation.

Acute decompression is reserved for respiratory failures. Eligibility criteria for who may undergo outpatient thyroid surgery have been debated in the literature. No consensus has been reached for these criteria. For now, there is consensus that some patients (high risk of bleeding) will require inpatient procedure, and in carefully selected groups of patients outpatient thyroid surgery is already performed, as the inclusion criteria below. Outpatient hemithyroidectomy has shown low number of complications in retrospective studies as well as high patient acceptance and economical advantage in recent prospective and retrospective studies studies. However, recent national and international studies recommend against outpatient procedure, mainly due to the risk of late cervical haemorrhage. It is therefore important to continue to investigate whether hemithyroidectomyis feasible as an outpatient procedure, especially considering patient safety and acceptance. This will be done in a randomized controlled trial where half of the patients are allocated to outpatient procedure and the other half to inpatient procedure. The aim is non-inferiority comparing the two above-mentioned procedures. As far as the authors know, no previous RCT has been done or published with this purpose.

Inclusion Criteria:

The hospitals normal outpatient criteria (ASA II or I), adult person to stay

with patient on night of surgery) Euthyroid Normal function of vocal cords preoperatively Lives within a 30 km radius or within 45 minutes away with ambulance, from the hospital Speaks Danish

Exclusion Criteria:

Suspected malignancy Previous thyroid or major neck surgery Intrathoracic thyroid gland Former treatment with radioactive iodine Anticoagulation treatment except ASA and ADP inhibitors

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