Thyroidectomy under local anaesthesia in India

Introduction

Contemporary thyroid surgery is almost exclusively performed under general anaesthesia (GA) – the use of local anaesthesia (LA) for thyroid surgery was abandoned many decades ago. Historically, its primary application appears to have been in the safe surgical management of patients with thyrotoxicosis when placing these patients under GA was considered to be risky. ¹ With the availability of very safe GA, this was no longer necessary. Recently, however, interest has resurfaced in the use of LA and regional anaesthesia for selected patients requiring thyroid surgery. ²

Given our limited accessibility to skilled anaesthetists in rural India, and the constant problem of scarcity of resources, we revisited the old practice of performing thyroid surgeries using LA. There is a report from a remote rural Ugandan hospital which, although it lacked close post-operative monitoring, showed surgery under LA to be the safest option for the removal of a 1.9 kg goitre. ³

Eleven patients underwent hemi-thyroidectomy under LA for benign disease between March 2000 and October 2001. Two more had surgery for a similar pathology in the next eight months: their mean age was 34.4 (21–52). Two of the patients were men. The reason for a gap between the cases was the absence of the primary surgeon from the country. All the cases were performed in a 60-bed rural hospital serving a population of 130,000 with a basic operating theatre facility; a qualified anaesthetist was present for three of the cases.

All patients who required thyroid surgery were examined for suitability. The best candidates are young, healthy, emotionally stable individuals who are well informed and willing to participate in the entire perioperative process. We excluded the following categories of patients: •

Obese patients;

We started thyroid surgery under LA as most rural patients dread coming to a tertiary centre for health care. As we were on a learning curve we only undertook surgery on patients with proven benign lesions on fine needle aspiration cytology with thin necks who wanted surgery for cosmetic reasons. No statistics of patients referred to our tertiary centre for thyroid surgery was maintained, but it would be about three or four every year. With increasing experience we intend to take patients for completion/total thyroidectomy, if warranted.

Once an appropriate patient was identified, we carefully prepared the patient for the procedure. This is perhaps the most important aspect of the entire process. The patient was informed step-by-step of the premedication, placement of an intravenous line, monitoring devices, surgical preparation and general operating room activity. Patients were reassured that they would be given whatever amount of medication was necessary to complete the procedure comfortably and safely.

We used a modified technique of cervical block as described by Yerzingatsian. ⁵ All patients had a bilateral superficial cervical plexus block using 1.0% Xylocaine with adrenaline (2–3 mL/kg body weight). With the patient's chin turned to the opposite side, a 23G needle was introduced at a point midway along the posterior border of the sternocleidomastoid (SCM) muscle into the subcutaneous tissues of the superficial compartment and a superficial cervical block was performed. The point where the external jugular crosses the posterior border of the muscle, we found to be a useful landmark for the cutaneous nerve branches. The next step was to withdraw the needle and reinforce it at the midpoint of the anterior border of the SCM infiltrating the platysma towards the midline. For each bolus we used 6–8 mL of the anaesthetic. The operation was then commenced with further LA, allowing infiltration of the layers if there was any discomfort. This was not needed in most cases. Once the isthmus was seen we infiltrated about 1 mL of 1.0% plain Xylocaine in the groove between the thyroid and the trachea, and found that the discomfort due to traction on the gland was reduced.

Patients were able to respond to verbal commands depending on their level of sedation, for which midazolam was used. They were monitored and reassured by either an intern or a nurse throughout the procedure. The time taken was marginally more for the first few cases as we had to get used to the occasional movement of the operating field due to swallowing, coughing or patient movement. ⁴ We used approximately 40 mL of an LA agent in each case, well within the safe maximum dosage of 50 mL for 1% lignocaine with adrenaline. One patient needed some nitrous oxide to enable completion of the procedure. Conversion to LA was not required in any patient.

Outcomes with regard to complications, perception of pain and other surgical parameters were acceptable based on completion of the procedure under LA with minimal or no patient discomfort. There were no wound haematomas and no complications relating to the recurrent laryngeal nerve. They were all discharged on the second postoperative day. In addition, there was significant cost savings for the patient. Being a rural hospital our overheads are low and a patient would pay USD110 for surgery which in our tertiary centre would normally cost USD260.

In conclusion, in selected, well-prepared patients thyroidectomy under LA is possible, safe, and economical with negligible morbidity.