Complications of thyroid and parathyroid surgery

Today most complications of thyroid and parathyroid surgery are related to either metabolic derangements or injury to the recurrent laryngeal nerves. Other complications include superior laryngeal nerve injury, infection, airway compromise, and bleeding. Although the principal goal of thyroid and parathyroid surgery is the prevention of these complications, prompt recognition and intervention will minimize morbidity and provide the patient with the best chance of a satisfactory outcome.     

Intraoperative parathyroid hormone levels in thyroid and parathyroid surgery

OBJECTIVE: To determine the utility of intraoperative parathyroid hormone measurement in predicting postoperative hypocalcemia after thyroid and parathyroid surgeries that places total parathyroid function at risk. STUDY DESIGN: Retrospective case review. METHODS: The case records of 23 patients undergoing total or completion thyroidectomy and 30 patients undergoing parathyroid exploration were reviewed. All patients had intraoperative parathyroid hormone levels measured. Samples were taken before dissection and 10 minutes after the resection was completed. Serial ionized calcium levels were measured in the postoperative period. Percentages of reduction in PTH levels from preoperative to postresection levels were calculated. Percentages of reduction in PTH level and the absolute value of the intraoperative PTH values were compared with postoperative ionized calcium levels. RESULTS: In the 23 patients who underwent thyroid surgery, the average preoperative and postoperative PTH values were 50 pg/mL (range, 17-87 pg/mL) and 34 pg/mL (range, 4-93 pg/mL), respectively. The average decrease in PTH was 39% (range, 39%-90%). The incidence of hypocalcemia was significantly higher in patients with intraoperative PTH levels less than 15 pg/mL relative to patients with PTH levels greater than 15 pg/mL in this setting ( P=.006). In the 30 patients who underwent parathyroid exploration, average preoperative and postoperative PTH levels were 291 pg/mL (range, 65-1675 pg/mL) and 113.8 pg/mL (range, 6.5-1263 pg/mL) respectively. The intraoperative PTH level did not correlate with postoperative calcium levels in the parathyroid group. Percentages of decrease in PTH levels greater than 60% was statistically associated with surgical cure in this population. CONCLUSIONS: The study demonstrates that intraoperative PTH levels greater than 15 pg/mL after total or completion thyroidectomy indicate a low risk of postoperative hypocalcemia and that these patients may be candidates for outpatient surgery. In the parathyroid group, intraoperative PTH levels do not correlate well with postoperative calcium levels.     

Prevention and management of complications in parathyroid surgery

The most common complication of parathyroid surgery is operative failure. Recurrent laryngeal nerve paralysis, permanent hypoparathyroidism,hematoma, and error in diagnosis can also complicate initial parathyroid exploration. This article discusses specific ways to try to prevent these and other problems and gives detailed strategies to evaluate and manage affected patients.     

Perioperative parathyroid hormone levels in thyroid surgery

OBJECTIVE: Perioperative hypocalcemia from temporary parathyroid gland dysfunction is common after thyroid surgery. No reliable cutoff values for parathyroid hormone (PTH) and the subsequent possibility of developing hypocalcemia exist. The purpose of this study is to determine a criterion for predicting hypocalcemia based on different PTH levels as cutoff values. STUDY DESIGN: Retrospective chart review. METHODS: A centralized database of intraoperative PTH levels was analyzed. PTH values approximately 10 minutes after excision of the thyroid gland and in the recovery room were obtained; serial ionized calcium levels were also analyzed. PTH values were then compared using chi-square analysis with significance defined as P < .05. A receiver operator characteristic (ROC) curve was also constructed to define sensitivities and specificities of different PTH levels as potential cutoff values. RESULTS: Eighty patients were identified meeting the study criteria between January 1999 and February 2005. Fourteen of the 80 (17.5%) patients became hypocalcemic during the hospital stay; none experienced permanent hypocalcemia. Patients who became hypocalcemic during their hospitalization were more likely to have a PTH level below 15 pg/mL (P < .01). Patients with a PTH level less than 15 pg/mL were more likely to develop hypocalcemia (P < .01). Finally, an ROC curve was constructed, allowing the surgeon to determine acceptable sensitivities and specificities and various PTH cutoff values. CONCLUSION: Low perioperative PTH levels significantly correlate with the presence of postoperative hypocalcemia but cannot be used to predict it. Using the ROC curve allows different chosen cutoff values to predict hypocalcemia with varying sensitivity and specificity.     

Surgical considerations and controversies in thyroid and parathyroid surgery

The techniques of thyroid surgery have been fully elucidated in several surgical texts and atlases. This article discuss surgical pearls of thyroid and parathyroid surgery. We discuss preoperative, intraoperative, and postoperative considerations and controversies for both procedures.     

甲状腺及甲状旁腺术中神经监测的研究现状

喉返神经及喉上神经的保护一直是甲状腺及甲状旁腺手术中的重点和难点,传统方式通常为视觉暴露或区域保护,但是颈部手术空间狭小,上述方法具有一定局限性.现阶段多借助于神经监测,该技术的使用有助于降低手术难度,缩短手术时间.甲状腺术中神经监测是神经电生理在临床中的良好应用,有助于更好地保护喉返神经及喉上神经.本文通过结合近年最...     

甲状腺外科手术操作与手术并发症的相关性

目的 了解甲状腺外科手术操作与手术并发症的相关性,探讨辨认及保护喉返神经、喉上神经外支、甲状旁腺的甲状腺切除术在治疗甲状腺肿物中的作用,以提高甲状腺肿物的手术治愈率,并减少手术并发症。方法 回顾分析甲状腺良性肿瘤或甲状腺癌患者152例临床资料,甲状腺切除采用"精细化被膜解剖"技术,术中辨认及保护喉返神经、喉上神经外支、甲状旁腺。结果 152例患者中,行喉返神经探查262侧,均成功辨认及保护;行喉上神经外支探查231侧,174例成功辨认(75.3%)。原位解剖保护甲状旁腺150例,行甲状旁腺移植术2例。术后发生单侧暂时性喉返神经麻痹1例,在术后3个月内恢复;无喉上神经外支功能障碍。术后发生暂时性甲状旁腺功能低下症13例,术后1周恢复9例, 4周后恢复3例, 5个月后恢复1例。无发生永久性甲状旁腺功能低下症、永久性喉返神经损伤和永久性喉上神经外支损伤病例。结论 术中辨认及保护喉返神经、喉上神经外支、甲状旁腺技术行甲状腺肿物切除术是安全的甲状腺手术操作,有效避免了永久性甲状旁腺功能低下症、喉返神经和喉上神经外支损伤并发症的发生。最大限度地保存了喉功能和甲状旁腺功能,提高了甲状腺肿物的手术治愈率。     

Recurrent laryngeal nerve. Identification during thyroid and parathyroid surgery

Intraoperative identification of the recurrent laryngeal nerve (RLN) is mandatory in surgery of the thyroid and parathyroid glands to avoid surgical damage. Several methods have been proposed for identifying and localizing the RLN based on vocal cord motion produced by electrical stimulation of the nerve. Most of them require complex instrumentation, while others are in contradiction with anatomical basis. We present a safe and simple method for identifying the RLN during thyroid and parathyroid gland surgery, which requires no additional surgical instruments and can be performed as a routine procedure. Nonetheless, thorough knowledge of cervical anatomy still remains the most important point in this surgery.     

Nonrecurrent laryngeal nerves: anatomic considerations during thyroid and parathyroid surgery

PURPOSE: In head and neck surgery, damage to the recurrent laryngeal nerve (RLN) during thyroid surgery is the most common iatrogenic cause of vocal cord paralysis. Identification of the RLNs and meticulous surgical technique can significantly decrease the incidence of this complication. Nonrecurrent RLNs (NRRLNs) are exceedingly rare. Surgeons need to be aware of their position to avoid damage to them. MATERIALS AND METHODS: A retrospective review of 513 RLN exposures over a 7-year period was performed. RESULTS: Two NRRLNs were encountered, for an incidence of 0.39%. CONCLUSION: NRRLNs are rare. Awareness of their existence will prevent the surgeon from accidentally severing one if it is encountered during routine thyroid or parathyroid surgery.     

Vagus nerve stimulation: quality control in thyroid and parathyroid surgery

This paper describes the use of the Neurosign 100 Nerve Monitor and vagus nerve stimulation in the identification and assessment of the integrity of the recurrent laryngeal nerve (RLN) during thyroid and parathyroid surgery. Vocal fold function was assessed pre- and post-operatively in all patients undergoing thyroid and parathyroid surgery. The nerve monitor, used in association with endotracheal electrodes, was used to confirm correct RLN identification and demonstrate its integrity at the completion of surgery. There were 21 unilateral and 19 bilateral neck explorations. In these 40 patients, 57 of 59 RLNs were identified. The nerve monitor demonstrated RLN continuity in all but one case (equipment failure: electrode misplacement) after initial identification. Vagus nerve stimulation was performed in 21 patients without adverse sequelae. Damage to the RLN was identified in one of these patients, in whom direct RLN stimulation close to the larynx had failed to indicate discontinuity. Post-operatively this patient had a transient unilateral vocal fold palsy. The use of the Neurosign 100 Nerve Monitor is no substitute for meticulous surgery. Stimulation of the vagus nerve may be a more sensitive means of assessing RLN integrity during thyroid and parathyroid surgery than stimulation of the RLN itself. Confirmation of RLN integrity allows the surgeon to proceed with confidence to the contralateral side of the neck during hazardous bilateral explorations.     

Prospective study of perioperative factors predicting hypocalcemia after thyroid and parathyroid surgery

OBJECTIVE: To identify whether perioperative 1,25-dihydroxyvitamin D or parathyroid hormone (PTH) levels will predict the development of hypocalcemia after thyroid and parathyroid surgery. DESIGN: Prospective study. SETTING: University hospital. PATIENTS: The study included 103 patients who underwent thyroid or parathyroid surgery between 2002 and 2004, with a comparison of the patients who underwent thyroid lobectomy (TL; n = 34), total thyroidectomy (TT; n = 27), parathyroid adenoma excision (PAE; n = 34), and subtotal parathyroidectomy for hyperplasia (SP; n = 8). MAIN OUTCOME MEASURES: Preoperative 1,25-dihydroxyvitamin D levels, number of patients requiring calcium replacement, and postoperative PTH and calcium levels. RESULTS: No patients in the TL or PAE group developed postoperative hypocalcemia that required calcium replacement. Six patients (22%) in the TT group and 3 patients (38%) in the SP group required calcium replacement for clinically significant hypocalcemia (P<.001). All patients who required calcium replacement had PTH levels of less than 15 pg/mL (1.6 pmol/L) 8 hours after surgery. Among the patients with postoperative PTH levels of less than 15 pg/mL (1.6 pmol/L) 8 hours after surgery, no patients in the PAE group required calcium replacement, compared with 75% of patients in the TT and SP groups (P<.001). The patients in the TT group had significantly lower postoperative calcium levels than those in the TL (P<.001) or the PAE (P<.005) group. The patients in the TL group reached stable calcium levels significantly earlier than those in the other groups (15.8 hours after surgery; P<.05). There was no relationship between preoperative 1,25-dihydroxyvitamin D levels and postoperative calcium levels. CONCLUSIONS: Preoperative 1,25-dihydroxyvitamin D levels were not predictive of postoperative calcium levels. Patients who undergo PAE or TL are at extremely low risk for requiring calcium replacement. Patients who undergo TT or SP with 8-hour postoperative PTH levels greater than or equal to 15 pg/mL (1.6 pmol/L) are at low risk for developing postoperative hypocalcemia, whereas those with PTH levels less than 15 pg/mL (1.6 pmol/L) have a high risk of developing hypocalcemia.     

The use of drains following thyroid and parathyroid surgery: a meta-analysis

The use of suction drains following thyroid and parathyroid surgery is controversial. Although there have been several prospective and retrospective studies carried out on this subject, no paper had sufficient power to provide a suitable answer to whether or not drains should be used routinely. We present the first formal meta-analysis of the data from eight randomized controlled trials on this subject. The result of the meta-analysis showed that there is no difference in complication rates between patients in whom drains have been used routinely and those in whom they have not.     

Perioperative parathyroid hormone levels in thyroid surgery: preliminary report

OBJECTIVES/HYPOTHESIS: An immediate method of accurately predicting postoperative hypocalcemia after total thyroidectomy would allow for selective early discharge of patients at low risk. The objective of the study was to determine the utility of perioperative parathyroid hormone measurement in predicting postoperative hypocalcemia after a thyroid surgery that places total parathyroid function at risk. STUDY DESIGN: Prospective case series. METHODS: Twenty-seven patients undergoing total or completion thyroidectomy had three blood samples drawn for parathyroid hormone measurement before dissection, 10 minutes after specimen removal, and in the recovery room. Serial ionized calcium levels were measured in the postoperative period. Preoperative, postresection, and recovery room levels were compared with postoperative ionized calcium levels. RESULTS: The average values before resection, after resection, and in the recovery room were 69.3 (range, 13-163), 42.3 (range, 0-120), and 37.4 (range 7-79) pg/mL, respectively. The incidence of hypocalcemia was 11% (3 of 27 patients). The rate of hypocalcemia was significantly higher (50%) in patients with recovery room parathyroid hormone values of 10 pg/mL or less relative to patients with recovery room parathyroid hormone values greater than 10 pg/mL (4%) in this setting (P =.01). Among patients with a parathyroid hormone value of less than 15 pg/mL in the recovery room, an increasing parathyroid hormone level in the recovery room relative to the level after resection predicted normocalcemia without calcium supplementation on chi analysis (P =.01). CONCLUSION: The study demonstrated that perioperative parathyroid hormone values can help predict patients who are at highest risk for postoperative hypocalcemia after thyroid surgery.     

Paraganglioma surgery: complications and treatment

Paragangliomas are vasculature in nature and are surrounded by vital neurovascular structures. The extirpation of these lesions requires careful preoperative evaluation, meticulous surgical technique, and the aid of experienced skull base surgical and rehabilitative teams. When surgery is performed in this way, complications can be minimized, and the function of the upper aerodigestive tract can be protected.     

Complications of thyroid and parathyroid surgery. Retrospective study and review of the literature

The number of ORL surgeons performing thyroid and parathyroid glands interventions is increasing more. Most of these surgeries are successful for us and our patients specially. However, this kind of operation can result in complications such as hypocalcemia and recurrential palsy, transitory or permanent, that it is necessary to know and avoid as far as possible. We are reporting a retrospective study of 12 years, based on our personal experience, where the real complications are analysed in 615 operated patients (500 with thyroid pathology and other 115 with parathyroid affectation) and after a comparation between both groups. The percentages of hypocalcemias were 25.6% and 24.3%, respectively. While in thyroid surgery (TS) the recurrential palsies showed a 6.6%, in parathyroid surgery (PS) were 0.8% only. The anatomical-embriologic knowledge, meticulousness and experience are three main qualities that are able to reduce the number of complications in the surgery of thyroid and parathyroid glands.     

Postoperative complications of surgery for malignant tumors of the thyroid gland

In order to assess the main complications following surgical treatment of thyroid neoplasms, a prospective-historical study was made in 145 patients operated between 1985 and 1997. Permanent hypocalcemia was encountered in 3.3% of our cases, and unilateral nerve injury in 2.2%, with 0.7% of fatal complications. The remain complications evaluated include: serohematoma, postoperative bleeding, and wound infection. To sum up, surgery of the thyroid neoplasms is a relatively safety procedure. The incidence of complications is similar to the surgical treatment of the remainder thyroid diseases.