ORIGINAL ARTICLE
Pain and surgical outcomes with and without neck extension in standard open thyroidectomy: A prospective randomized trial Brian Hung-Hin Lang, MS, FRACS,1* Sze-How Ng, MBBS, MS,2 Kai Pun Wong, MBBS, FRCS1 1
Department of Surgery, University of Hong Kong, Pokfulam, Hong Kong SAR, China, 2Department of Surgery, Kuala Lumpur Hospital, Kuala Lumpur, Malaysia.
Accepted 9 January 2014 Published online 25 April 2014 in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/hed.23611
ABSTRACT: Background. The purpose of this study was to compare surgical outcomes between those patients who underwent open thyroidectomy with and without neck extension. Methods. One hundred eighty patients were randomized into 2 groups, with neck extension (group I) and without neck extension (group II). Outcomes included pain score on postoperative day 0, day 1, and the first clinic visit, operating time, blood loss, recurrent laryngeal nerve (RLN) injury, and hypoparathyroidism. Results. Pain scores in group II were significantly lower on postoperative day 1 (2.38 vs 3.08; p 5 .022) and at the first clinic visit (0.57 vs 0.78; p 5 .026). There was a significant direct correlation between degree of neck
INTRODUCTION Thyroidectomy is one of the most commonly performed surgical procedures and, in experienced hands, the associated surgical morbidity is acceptably low.1,2 Relative to other surgically related morbidities like recurrent laryngeal nerve (RLN) injury and hypoparathyroidism, pain after thyroidectomy has been less well studied and understood.3–6 Nevertheless, postoperative pain is an important outcome parameter as increased pain tends to adversely affect the overall patient perception and satisfaction of the operation.7 Preoperative strategies, like cervical plexus block and steroid injection, have been proposed to reduce postoperative pain and analgesic requirement.5,6 The degree of neck extension at the time of operation has been proposed as a possible source for pain after thyroidectomy.8–10 Unlike wound pain, pain derived from neck extension often localizes at the back of the neck and shoulder area.7–10 Although a certain degree of neck extension is often thought necessary for the surgeon to gain better access to the thyroid lobe and to gain adequate exposure to vital structures, such as the RLN and parathyroid glands, hyperextension of the neck at the time of operation not only potentially increases the severity of neck pain but also leads to other uncommon but serious events like intraoperative stroke, spinal damage, and quadraparesis in patients with cervical canal steno-
extension and pain score on day 1 (p 5 .159 and p 5 .033). Other outcomes seemed comparable. However, the overall RLN injury rate was not significantly different between the 2 groups (5.3% vs 2.0%; p 5 .212). Conclusion. Compared to group I, pain on postoperative day 1 and at the first visit in group II were significantly less, but both groups had similar C 2014 Wiley Periodicals, Inc. Head Neck 37: overall RLN injury rate. V 407–412, 2015
KEY WORDS: randomized trial, postoperative pain, analgesia, thyroidectomy, hypoparathyroidism, postoperative hypocalcemia, recurrent laryngeal nerve, neck extension
sis.8,11,12 Furthermore, 1 previous study found that excessive neck extension did not significantly improve the thyroid gland access.8 To our knowledge, few studies have critically examined the association between the amount of neck extension during thyroidectomy and pain after thyroidectomy and to see whether reducing the amount of neck extension would lessen the pain. We postulated that reduced neck extension would reduce postoperative pain. Before this randomized trial, 30 consecutive open thyroidectomies without neck extension were performed and were found to be feasible and safe. Given that postoperative pain is often worse over the first 24 hours after operation,5–7 the present prospective randomized trial aimed to compare the severity of pain on the first postoperative day and surgically related complications between those who underwent thyroidectomy with neck extension and those without neck extension.
PATIENTS AND METHODS Approval was obtained from the local institutional review board (UW 12-062) before enrolling patients to this study. Patients were subsequently enrolled after obtaining permission. The enrollment process occurred before the operation. Consent forms and process were audited by the institutional review board. The study was registered with clinicaltrial.gov at the inception of enrollment (NCT01620151).
Eligibility criteria *Corresponding author: B. H. H. Lang, Division of Endocrine Surgery, Department of Surgery, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong SAR, China. E-mail: [email protected]
All patients aged between 18 and 80 years at the time of elective open thyroidectomy at 2 institutions were
HEAD & NECK—DOI 10.1002/HED
MARCH 2015
407
LANG ET AL.
considered potential candidates for this trial. The exclusion criteria were history of bleeding disorder and tendency, cervical spine surgery and disease, RLN injury and hypocalcemia, mental disorder and low intelligence (ie, not able to provide a reliable pain score), and pregnancy. Also, those requiring concomitant surgical procedure, including parathyroidectomy or neck dissection, were excluded.
Study design All eligible patients were randomized after induction into 2 groups, namely the “neck extension” group (group I) and the “no neck extension” group (group II). For group I, after positioning the patient in a supine position with arms tucked and head up to 30 from the horizontal plane, a standard shoulder roll was placed behind the patient’s shoulders to extend the neck before incision (Figure 1). For group II, after similar positioning with arms tucked and head up to 30 , no standard shoulder roll was placed behind the shoulders. For all cases, the head was secured in a head ring. To compare the extent of neck extension between the 2 groups, the distance between the cricoid cartilage to the sternal notch before and after placement of the shoulder roll was measured to the nearest millimeters and recorded. Also, before incision, the length of the incision was marked and measured. The length of incision was determined by 1 operating surgeon (B.H.L.) and was based on a combination of the patient’s body habitus, neck size, likely pathology, and thyroid size. The level of the incision was usually made 1.5 to 2 cm above the sternal notch along the closest natural crease. All procedures were performed by 1 surgeon (B.H.L.). Surgical techniques, postoperative care, and follow-up protocol has been previously described.3,4,13 Thyroidectomy was performed with the patients under general anesthesia using routine medications. All intraoperative pain medications given by the anesthetic team were the same or standardized throughout the study period. No local anesthesia or block was used. The strap muscles were separated in the midline and retracted laterally. The upper pole of the thyroid lobe was dissected and divided first. This was followed by visual RLN identification at its entry to the larynx (or Berry’s ligament) before further mobilization of the rest of the lobe. Parathyroid glands were routinely identified and preserved. Any devascularized parathyroid glands were immediately minced and autotransplanted to the ipsilateral sternocleidomastoid muscle. Wound drains were not used. Operative findings, such as weight of excised thyroid gland, number of parathyroid glands identified, and glands autotransplanted, were recorded. Time taken (in minutes) from skin incision to first upper thyroid pole division, from skin incision to first visual RLN identification, and from skin incision to closure were recorded.
Outcomes measured All patients were required to stay overnight at the hospital and received basic analgesic therapy with acetaminophen 2 g/day or 500 mg 4 times a day. Patients were allowed to have any breakthrough analgesia between regular doses while in the hospital. In the postoperative 408
HEAD & NECK—DOI 10.1002/HED
MARCH 2015
FIGURE 1. Patient positioning of the head up to 30 .
period after returning to the ward, patients were specifically asked about the severity of the pain and ache around the neck and shoulder area as these are common areas for soreness after neck extension. A standard visual analog score (VAS) was used to assess the severity using a scale of 0 (“absolutely no pain”) to 10 (“worse pain imaginable”) on day 0 (within 2 hours after surgery but before the first dose of acetaminophen), on the following morning on day 1 (approximately 18–20 hours after surgery but before the fourth dose of acetaminophen), and at the first clinic visit (ie, 10 days after operation). No analgesia was given in the recovery room or at hospital discharge. To ensure their compliance after hospital discharge, patients were specifically asked whether they took any analgesia at home at their first clinic visit. The assessor for the postoperative neck pain was blinded to the study results during the postoperative course. For bilateral thyroid resection, serum calcium and phosphate were regularly measured. The parathyroid hormone (PTH) levels were also taken immediately at the time of skin closure (PTH-SC; approximately 5–10 minutes after thyroid gland removal) and on the following morning on postoperative day 1 (PTH-D1). Serum calcium (Ca) was checked preoperatively, within 1 hour after operation (Ca-D0), on the following morning (Ca-D1), and every 8 to 10 hours until stabilization. Calcium 6 vitamin D supplements were prescribed for symptomatic hypocalcemia or if adjusted calcium 6 months were categorized as permanent hypoparathyroidism. Both vocal cords were examined by direct laryngoscopy 1 day before and 1 week after thyroidectomy. Any reduction in movement was recorded as paresis. Those with paresis were reassessed every 4 to 6 weeks until full recovery. The presence of cord paresis lasting >6 months was regarded as permanent. To calculate RLN injury rates, the number of nerves at risk was used as the denominator.
REDUCED
FIGURE 2. The overall design and conduct of the prospective randomized trial.
Sample size Among the patients who underwent thyroidectomy with neck extension, the mean (6SD) pain score at postoperative day 1 from 2010 to 2011 was 3.0 (61.4). We hypothesized that the VAS score at postoperative day 1 would decrease by 20% in group II. To detect significance differences with a 2-tailed type 1 error of 5% and a statistical power of 80%, 90 patients were required in each group.
Assignment A computer-generated individual unit of randomization was utilized in a nonstratified sequence in blocks of 10. After consent for study enrollment was obtained, the randomization sequence was accessed to identify the next allotment. The operating surgeon did not obtain consent and was not involved with the enrollment process. All patients remained in their assigned group.
Statistics All data were collected prospectively by a single individual who had no role in clinical care. For comparison of dichotomous variables between group I and II, chi-square tests and Fisher’s exact tests were used. The Mann–Whitney U test was used for comparison of continuous variables. All statistical analyses were conducted using SPSS version 18.0 (SPSS, Chicago, IL). The Pearson’s correlation test was used to correlate 2 continuous variables. The p < .05 were considered statistically significant.
RESULTS Figure 2 shows the study design. Of the 238 consecutive patients who underwent elective open thyroidectomy at the 2 institutions, 58 (24.4%) were excluded because of age 80 years old (n 5 10), history of cervical spine surgery or disease (n 5 3), previous RLN injury and/or hypoparathyroidism (n 5 4), mental disorder/subnormal intelligence (n 5 4), and requiring concomitant surgical procedures (n 5 37). Table 1 shows a comparison of the baseline patient characteristics between the 2 groups. No significant differences were found between the 2 groups. Table 2 shows
PAIN WITHOUT NECK EXTENSION IN THYROIDECTOMY
a comparison of operative findings between the 2 groups. Extent of surgery, length of skin incision, and distance between the cricoid cartilage to the sternal notch before neck extension were similar between the 2 groups. The total number of RLNs at risk in group I and II were 147 and 150, respectively. As expected, after neck extension by the shoulder roll, the distance between the cricoid cartilage to the sternal notch was significantly longer in group I than II (55 mm vs 47 mm; p < .001), with a median percentage gained of 16.2% (6.5% to 40.0%). Operating time from skin incision to division of the first upper pole, skin incision to first visual RLN identification, and skin incision to closure were similar between the 2 groups. Volume of blood loss and the number of parathyroid glands identified and auto-transplanted were similar between the 2 groups. Table 3 shows a comparison of postoperative outcomes between the 2 groups. In group I, 9 patients (10.0%) requested analgesia once, whereas in group II, 5 patients (5.6%) requested analgesia once. The pain score on day 0 was similar between the 2 groups. Mean pain score on day 1 in group II was significantly lower than that of group I (2.38 vs 3.08; p 5 .022) and the proportion of patients with a pain score of 0 to 3 was more in group II (73.3% vs 65.6%).There was a significant direct correlation between the percentage of distance gained after neck extension and pain score on day 1 in group I (p 5 .159 and p 5 .033). There was also a significantly lower mean pain score at the first clinic visit (10–14 days after operation) in group II than in group I (0.57 vs 0.78; p 5 .026). Overall, there were 9 (3.0%) temporary RLN injuries with duration of paresis ranging between 1 and 4 months. Interestingly, although not significant, group II doubled the total RLN injury rate of group I (5.3% vs 2.0%; p 5 .212). Both permanent RLN injuries belonged to group II. One had persistent vocal cord paresis at 6 months and the other had complete vocal cord paralysis at 6 months on direct laryngoscopy. In group II, 6 of the injuries (including the 2 permanent injuries) occurred in the first 50 cases. The Ca-D0 was significantly higher in group II than in group I (p 5 .040) but the PTH-SC, PTH-D1, and postoperative CA-D1 were similar in the 2 groups. Other outcome parameters, including total morbidity, were similar in the 2 groups.
DISCUSSION Given that neck extension may induce pain and discomfort after thyroidectomy,8–10 the main purpose of this randomized trial was to evaluate whether the absence of neck extension during open thyroidectomy could lessen pain in the first postoperative day. Because the length of incision is a possible confounder in pain assessment,9,10 it was precisely measured before incision and was found comparable between the 2 groups (p 5 .615). However, other confounders, such as duration and degree of wound retraction, body habitus, and other surgical techniques, were not as easily accountable. Nevertheless, in terms of duration of wound retraction, because skin to upper pole, skin to RLN identification, and skin to skin total operating times were comparable in the 2 groups, it was probably not significantly different. Also, because the body mass index (BMI) and extent of operations were also HEAD & NECK—DOI 10.1002/HED
MARCH 2015
409
LANG ET AL.
TABLE 1. Comparison of baseline characteristics and surgical indication/final pathology between those with neck extension (group I) and those without neck extension (group II). Variables
Age at operation, y Sex, male:female BMI, kg/m2 Preoperative TSH level, mIU/L Antithyroglobulin antibody, titer 400 Antimicrosomal antibody, titer 400 Preoperative calcium level, mmol/L Surgical indication/final pathology Malignancy Graves disease toxic MNG Benign pathology Concomitant autoimmune thyroiditis Size/weight of excised gland, g
Group I (n 5 90)
Group II (n 5 90)
p value
49.2 (23.4–79.7) 15:75 23.3 (16.9–34.5) 0.875 (
Pain and surgical outcomes with and without neck extension in standard open thyroidectomy: A prospective randomized trial Brian Hung-Hin Lang, MS, FRACS,1* Sze-How Ng, MBBS, MS,2 Kai Pun Wong, MBBS, FRCS1 1
Department of Surgery, University of Hong Kong, Pokfulam, Hong Kong SAR, China, 2Department of Surgery, Kuala Lumpur Hospital, Kuala Lumpur, Malaysia.
Accepted 9 January 2014 Published online 25 April 2014 in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/hed.23611
ABSTRACT: Background. The purpose of this study was to compare surgical outcomes between those patients who underwent open thyroidectomy with and without neck extension. Methods. One hundred eighty patients were randomized into 2 groups, with neck extension (group I) and without neck extension (group II). Outcomes included pain score on postoperative day 0, day 1, and the first clinic visit, operating time, blood loss, recurrent laryngeal nerve (RLN) injury, and hypoparathyroidism. Results. Pain scores in group II were significantly lower on postoperative day 1 (2.38 vs 3.08; p 5 .022) and at the first clinic visit (0.57 vs 0.78; p 5 .026). There was a significant direct correlation between degree of neck
INTRODUCTION Thyroidectomy is one of the most commonly performed surgical procedures and, in experienced hands, the associated surgical morbidity is acceptably low.1,2 Relative to other surgically related morbidities like recurrent laryngeal nerve (RLN) injury and hypoparathyroidism, pain after thyroidectomy has been less well studied and understood.3–6 Nevertheless, postoperative pain is an important outcome parameter as increased pain tends to adversely affect the overall patient perception and satisfaction of the operation.7 Preoperative strategies, like cervical plexus block and steroid injection, have been proposed to reduce postoperative pain and analgesic requirement.5,6 The degree of neck extension at the time of operation has been proposed as a possible source for pain after thyroidectomy.8–10 Unlike wound pain, pain derived from neck extension often localizes at the back of the neck and shoulder area.7–10 Although a certain degree of neck extension is often thought necessary for the surgeon to gain better access to the thyroid lobe and to gain adequate exposure to vital structures, such as the RLN and parathyroid glands, hyperextension of the neck at the time of operation not only potentially increases the severity of neck pain but also leads to other uncommon but serious events like intraoperative stroke, spinal damage, and quadraparesis in patients with cervical canal steno-
extension and pain score on day 1 (p 5 .159 and p 5 .033). Other outcomes seemed comparable. However, the overall RLN injury rate was not significantly different between the 2 groups (5.3% vs 2.0%; p 5 .212). Conclusion. Compared to group I, pain on postoperative day 1 and at the first visit in group II were significantly less, but both groups had similar C 2014 Wiley Periodicals, Inc. Head Neck 37: overall RLN injury rate. V 407–412, 2015
KEY WORDS: randomized trial, postoperative pain, analgesia, thyroidectomy, hypoparathyroidism, postoperative hypocalcemia, recurrent laryngeal nerve, neck extension
sis.8,11,12 Furthermore, 1 previous study found that excessive neck extension did not significantly improve the thyroid gland access.8 To our knowledge, few studies have critically examined the association between the amount of neck extension during thyroidectomy and pain after thyroidectomy and to see whether reducing the amount of neck extension would lessen the pain. We postulated that reduced neck extension would reduce postoperative pain. Before this randomized trial, 30 consecutive open thyroidectomies without neck extension were performed and were found to be feasible and safe. Given that postoperative pain is often worse over the first 24 hours after operation,5–7 the present prospective randomized trial aimed to compare the severity of pain on the first postoperative day and surgically related complications between those who underwent thyroidectomy with neck extension and those without neck extension.
PATIENTS AND METHODS Approval was obtained from the local institutional review board (UW 12-062) before enrolling patients to this study. Patients were subsequently enrolled after obtaining permission. The enrollment process occurred before the operation. Consent forms and process were audited by the institutional review board. The study was registered with clinicaltrial.gov at the inception of enrollment (NCT01620151).
Eligibility criteria *Corresponding author: B. H. H. Lang, Division of Endocrine Surgery, Department of Surgery, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong SAR, China. E-mail: [email protected]
All patients aged between 18 and 80 years at the time of elective open thyroidectomy at 2 institutions were
HEAD & NECK—DOI 10.1002/HED
MARCH 2015
407
LANG ET AL.
considered potential candidates for this trial. The exclusion criteria were history of bleeding disorder and tendency, cervical spine surgery and disease, RLN injury and hypocalcemia, mental disorder and low intelligence (ie, not able to provide a reliable pain score), and pregnancy. Also, those requiring concomitant surgical procedure, including parathyroidectomy or neck dissection, were excluded.
Study design All eligible patients were randomized after induction into 2 groups, namely the “neck extension” group (group I) and the “no neck extension” group (group II). For group I, after positioning the patient in a supine position with arms tucked and head up to 30 from the horizontal plane, a standard shoulder roll was placed behind the patient’s shoulders to extend the neck before incision (Figure 1). For group II, after similar positioning with arms tucked and head up to 30 , no standard shoulder roll was placed behind the shoulders. For all cases, the head was secured in a head ring. To compare the extent of neck extension between the 2 groups, the distance between the cricoid cartilage to the sternal notch before and after placement of the shoulder roll was measured to the nearest millimeters and recorded. Also, before incision, the length of the incision was marked and measured. The length of incision was determined by 1 operating surgeon (B.H.L.) and was based on a combination of the patient’s body habitus, neck size, likely pathology, and thyroid size. The level of the incision was usually made 1.5 to 2 cm above the sternal notch along the closest natural crease. All procedures were performed by 1 surgeon (B.H.L.). Surgical techniques, postoperative care, and follow-up protocol has been previously described.3,4,13 Thyroidectomy was performed with the patients under general anesthesia using routine medications. All intraoperative pain medications given by the anesthetic team were the same or standardized throughout the study period. No local anesthesia or block was used. The strap muscles were separated in the midline and retracted laterally. The upper pole of the thyroid lobe was dissected and divided first. This was followed by visual RLN identification at its entry to the larynx (or Berry’s ligament) before further mobilization of the rest of the lobe. Parathyroid glands were routinely identified and preserved. Any devascularized parathyroid glands were immediately minced and autotransplanted to the ipsilateral sternocleidomastoid muscle. Wound drains were not used. Operative findings, such as weight of excised thyroid gland, number of parathyroid glands identified, and glands autotransplanted, were recorded. Time taken (in minutes) from skin incision to first upper thyroid pole division, from skin incision to first visual RLN identification, and from skin incision to closure were recorded.
Outcomes measured All patients were required to stay overnight at the hospital and received basic analgesic therapy with acetaminophen 2 g/day or 500 mg 4 times a day. Patients were allowed to have any breakthrough analgesia between regular doses while in the hospital. In the postoperative 408
HEAD & NECK—DOI 10.1002/HED
MARCH 2015
FIGURE 1. Patient positioning of the head up to 30 .
period after returning to the ward, patients were specifically asked about the severity of the pain and ache around the neck and shoulder area as these are common areas for soreness after neck extension. A standard visual analog score (VAS) was used to assess the severity using a scale of 0 (“absolutely no pain”) to 10 (“worse pain imaginable”) on day 0 (within 2 hours after surgery but before the first dose of acetaminophen), on the following morning on day 1 (approximately 18–20 hours after surgery but before the fourth dose of acetaminophen), and at the first clinic visit (ie, 10 days after operation). No analgesia was given in the recovery room or at hospital discharge. To ensure their compliance after hospital discharge, patients were specifically asked whether they took any analgesia at home at their first clinic visit. The assessor for the postoperative neck pain was blinded to the study results during the postoperative course. For bilateral thyroid resection, serum calcium and phosphate were regularly measured. The parathyroid hormone (PTH) levels were also taken immediately at the time of skin closure (PTH-SC; approximately 5–10 minutes after thyroid gland removal) and on the following morning on postoperative day 1 (PTH-D1). Serum calcium (Ca) was checked preoperatively, within 1 hour after operation (Ca-D0), on the following morning (Ca-D1), and every 8 to 10 hours until stabilization. Calcium 6 vitamin D supplements were prescribed for symptomatic hypocalcemia or if adjusted calcium 6 months were categorized as permanent hypoparathyroidism. Both vocal cords were examined by direct laryngoscopy 1 day before and 1 week after thyroidectomy. Any reduction in movement was recorded as paresis. Those with paresis were reassessed every 4 to 6 weeks until full recovery. The presence of cord paresis lasting >6 months was regarded as permanent. To calculate RLN injury rates, the number of nerves at risk was used as the denominator.
REDUCED
FIGURE 2. The overall design and conduct of the prospective randomized trial.
Sample size Among the patients who underwent thyroidectomy with neck extension, the mean (6SD) pain score at postoperative day 1 from 2010 to 2011 was 3.0 (61.4). We hypothesized that the VAS score at postoperative day 1 would decrease by 20% in group II. To detect significance differences with a 2-tailed type 1 error of 5% and a statistical power of 80%, 90 patients were required in each group.
Assignment A computer-generated individual unit of randomization was utilized in a nonstratified sequence in blocks of 10. After consent for study enrollment was obtained, the randomization sequence was accessed to identify the next allotment. The operating surgeon did not obtain consent and was not involved with the enrollment process. All patients remained in their assigned group.
Statistics All data were collected prospectively by a single individual who had no role in clinical care. For comparison of dichotomous variables between group I and II, chi-square tests and Fisher’s exact tests were used. The Mann–Whitney U test was used for comparison of continuous variables. All statistical analyses were conducted using SPSS version 18.0 (SPSS, Chicago, IL). The Pearson’s correlation test was used to correlate 2 continuous variables. The p < .05 were considered statistically significant.
RESULTS Figure 2 shows the study design. Of the 238 consecutive patients who underwent elective open thyroidectomy at the 2 institutions, 58 (24.4%) were excluded because of age 80 years old (n 5 10), history of cervical spine surgery or disease (n 5 3), previous RLN injury and/or hypoparathyroidism (n 5 4), mental disorder/subnormal intelligence (n 5 4), and requiring concomitant surgical procedures (n 5 37). Table 1 shows a comparison of the baseline patient characteristics between the 2 groups. No significant differences were found between the 2 groups. Table 2 shows
PAIN WITHOUT NECK EXTENSION IN THYROIDECTOMY
a comparison of operative findings between the 2 groups. Extent of surgery, length of skin incision, and distance between the cricoid cartilage to the sternal notch before neck extension were similar between the 2 groups. The total number of RLNs at risk in group I and II were 147 and 150, respectively. As expected, after neck extension by the shoulder roll, the distance between the cricoid cartilage to the sternal notch was significantly longer in group I than II (55 mm vs 47 mm; p < .001), with a median percentage gained of 16.2% (6.5% to 40.0%). Operating time from skin incision to division of the first upper pole, skin incision to first visual RLN identification, and skin incision to closure were similar between the 2 groups. Volume of blood loss and the number of parathyroid glands identified and auto-transplanted were similar between the 2 groups. Table 3 shows a comparison of postoperative outcomes between the 2 groups. In group I, 9 patients (10.0%) requested analgesia once, whereas in group II, 5 patients (5.6%) requested analgesia once. The pain score on day 0 was similar between the 2 groups. Mean pain score on day 1 in group II was significantly lower than that of group I (2.38 vs 3.08; p 5 .022) and the proportion of patients with a pain score of 0 to 3 was more in group II (73.3% vs 65.6%).There was a significant direct correlation between the percentage of distance gained after neck extension and pain score on day 1 in group I (p 5 .159 and p 5 .033). There was also a significantly lower mean pain score at the first clinic visit (10–14 days after operation) in group II than in group I (0.57 vs 0.78; p 5 .026). Overall, there were 9 (3.0%) temporary RLN injuries with duration of paresis ranging between 1 and 4 months. Interestingly, although not significant, group II doubled the total RLN injury rate of group I (5.3% vs 2.0%; p 5 .212). Both permanent RLN injuries belonged to group II. One had persistent vocal cord paresis at 6 months and the other had complete vocal cord paralysis at 6 months on direct laryngoscopy. In group II, 6 of the injuries (including the 2 permanent injuries) occurred in the first 50 cases. The Ca-D0 was significantly higher in group II than in group I (p 5 .040) but the PTH-SC, PTH-D1, and postoperative CA-D1 were similar in the 2 groups. Other outcome parameters, including total morbidity, were similar in the 2 groups.
DISCUSSION Given that neck extension may induce pain and discomfort after thyroidectomy,8–10 the main purpose of this randomized trial was to evaluate whether the absence of neck extension during open thyroidectomy could lessen pain in the first postoperative day. Because the length of incision is a possible confounder in pain assessment,9,10 it was precisely measured before incision and was found comparable between the 2 groups (p 5 .615). However, other confounders, such as duration and degree of wound retraction, body habitus, and other surgical techniques, were not as easily accountable. Nevertheless, in terms of duration of wound retraction, because skin to upper pole, skin to RLN identification, and skin to skin total operating times were comparable in the 2 groups, it was probably not significantly different. Also, because the body mass index (BMI) and extent of operations were also HEAD & NECK—DOI 10.1002/HED
MARCH 2015
409
LANG ET AL.
TABLE 1. Comparison of baseline characteristics and surgical indication/final pathology between those with neck extension (group I) and those without neck extension (group II). Variables
Age at operation, y Sex, male:female BMI, kg/m2 Preoperative TSH level, mIU/L Antithyroglobulin antibody, titer 400 Antimicrosomal antibody, titer 400 Preoperative calcium level, mmol/L Surgical indication/final pathology Malignancy Graves disease toxic MNG Benign pathology Concomitant autoimmune thyroiditis Size/weight of excised gland, g
Group I (n 5 90)
Group II (n 5 90)
p value
49.2 (23.4–79.7) 15:75 23.3 (16.9–34.5) 0.875 (
