Administration of neostigmine after tracheal intubation shortens time to successful intraoperative neuromonitoring during thyroid surgery: a randomized controlled trial

This prospective, randomized controlled trial evaluated the effect of neostigmine for intraoperative neuromonitoring (IONM) during thyroid surgery. Forty subjects undergoing thyroidectomy with IONM, randomized into neostigmine administration after tracheal intubation (Group N, n = 20) or control treatment with normal saline (Group C, n = 20), completed the trial. Electromyography amplitudes of the vagus nerve (V1) were recorded before thyroid dissection. The time from the initial V1 signal check to successful V1 stimulation was recorded. In Group N, all the patients had a successful V1 signal at the first check, whereas ten (50%) patients in Group C had a time delay between the initial V1 check and successful V1 (p < 0.001). The mean delay time among the delayed patients in Group C was 11.2 ± 1.4 min. The mean time from skin incision to successful V1 stimulation was significantly shorter in Group N than in Group C (15.4 ± 2.4 min vs. 19.9 ± 5.7 min, p = 0.003). In Groups N and C, the mean V1 amplitudes were 962.2 ± 434.5 μV vs. 802.3 ± 382.7 μV (p = 0.225), respectively, and the mean R1 amplitudes were 1240.0 ± 836.5 μV vs. 1023.4 ± 455.8 μV (p = 0.316), respectively. There was one bucking event in Group N. In conclusion, neostigmine administration immediately after tracheal intubation can be useful to reverse neuromuscular blockade for successful IONM in thyroid surgeries.

Investigation of potential neuropharmacological activity of neostigmine-glycopyrrolate for intraoperative neural monitoring in thyroid surgery

Intraoperative neuromonitoring (IONM) is frequently used in thyroid surgery to reduce recurrent laryngeal nerve injury. The use of neuromuscular blockade agent to facilitate tracheal intubation, is a common cause of IONM failure. We performed a retrospective analysis to assess the efficacy of neostigmine-glycopyrrolate as a neuromuscular blockade reversal agent for IONM during thyroid surgery. Rocuronium (0.6 mg/kg) was administered for muscle relaxation. Neostigmine (2 mg) and glycopyrrolate (0.4 mg) were administered immediately after intubation. Cricothyroid muscle-twitch response upon external branch of superior laryngeal nerve stimulation and electromyography amplitudes of vagal and recurrent laryngeal nerves before (V1, R1) and after thyroid resection (V2, R2) were recorded. Fifty patients (23 males, 27 females) were included in the analysis. The diagnoses comprised 43 papillary thyroid carcinomas and seven benign diseases. The mean time between rocuronium injection and neostigmine-glycopyrrolate injection was 5.1 ± 1.2 min, and the mean time from neostigmine-glycopyrrolate injection to successful cricothyroid muscle twitching upon external branch of superior laryngeal nerve stimulation was 21.0 ± 4.5 min. All patients had V1 and R1 amplitudes of more than 500 μV each, with mean V1 and R1 amplitudes of 985.3 ± 471.6 μV and 1177.2 ± 572.7 μV, respectively. Neostigmine-glycopyrrolate was effectively used as a neuromuscular blockade reversal agent for IONM in thyroid surgeries without a significant increase in bucking events. Administration of neostigmine-glycopyrrolate immediately after intubation can be recommended for successful NMB reversal to facilitate IONM during thyroid surgery.

Treatment of Differentiated Thyroid Cancer and Recurrent Laryngeal Nerve Function with 131 Iodine Based on Positron Emission Tomography/Computed Tomography Image Segmentation Algorithm

BACKGROUND

Based on the positron emission tomography (PET) computed tomography (CT) image segmentation algorithm, this article explores the application of PET/CT in the recurrence and metastasis of thyroid cancer after differentiated thyroid cancer (DTC).

METHODS

In this study, 132 patients with DTC combined with ¹³¹I treatment underwent PET/CT whole-body imaging and ¹³¹I whole-body scan (¹³¹I-WBS), and the serum thyroglobulin (Tg) level was measured at the same time.

RESULTS

Among 54 Tg-positive patients, 49 were positive for ¹³¹I-WBS and 32 were positive for PET/CT imaging. Of the 15 Tg-negative patients, ¹³¹I-WBS and PET/CT imaging were negative. Three patients with ¹³¹I-WBS suggesting residual thyroid tumors were all positive in PET/CT examinations; 7 patients with ¹³¹I-WBS suggesting lymph node metastasis were all positive in PET/CT examinations, and in ¹³¹I, PET/CT imaging in WBS-negative patients showed 6 lung metastases and 3 bone metastases.

CONCLUSIONS

PET/CT and ¹³¹I scans are similar in the diagnosis of residual thyroid and lymph node metastasis, but PET/CT has more advantages than does the ¹³¹I scan in the diagnosis of bone metastasis and lung metastasis. PET/CT can still find other benign and malignant lesions, which is of great value in the restaging of DTC. The imaging effect of WBS lung lesions in older patients is not good. The presence of stripe, calcification, and patch shadows in the lungs is not conducive to the imaging of WBS lung metastases. Lung strips and calcification affect the WBS lung main factors for imaging of metastases.