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ORIGINAL ARTICLE
Year : 2014  |  Volume : 41  |  Issue : 1  |  Page : 10-15

Technique of clamp-tie thyroidectomy versus Harmonic focus R . Is there a need for technology?


Department of Surgery, Lady Reading Hospital, Peshawar, Pakistan

Date of Web Publication7-Feb-2014

Correspondence Address:
Adil Bangash
Department of Surgery, Lady Reading Hospital, Peshawar
Pakistan
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0974-5009.126704

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  Abstract 

Aims and Objectives: The aim of this study was to compare operative times and frequency of complications between groups for total thyroidectomy without evidence of malignancy. Materials and Methods: This interventional (experimental) controlled trial was conducted at Lady Reading Hospital from 11 th June, 2010 to 10 th June, 2012 and included 120 patients. Group 1 included those patients that underwent total thyroidectomy using the Harmonic Focus R , whereas Group 2 included all those patients that underwent total thyroidectomy by a clamp-tie technique. The data following collection was entered onto the SPSS version 16.0 for Windows R and analyzed. Results: The demographic data in comparison by the two groups saw no significant difference (P = 0.822). Age ranges were also similar, but late age was not a common finding. The mean operative time was lower in the Group 1 (55.3 [±12.1] min) versus (71.6 [±18.2] min) for Group 2. The other significant differences observed in the mean hospital stay (P = 0.031) and mean blood in the drain at 24 h was 55.6 (±11.34) ml in Group 1 versus 83.7 (±21.4) ml for Group 2 (P = 0.001). The frequency of persistent hypocalcemia and hoarseness was observed in the conventional clamp-tie group. Conclusion: The use of ultrasonic dissector is safe and significantly reduces operative time. The frequency of hypoparathyroidism inferred from hypocalcemia persisting beyond 1 month was greater in the conventional clamp-tie group as was the amount of blood in the drain at 24 h.

Keywords: Conventional clamp-tie technique, Harmonic focus, total thyroidectomy, ultrasonic dissector


How to cite this article:
Bangash A, Khan N, Azeem I, Sadiq M. Technique of clamp-tie thyroidectomy versus Harmonic focus R . Is there a need for technology?. J Sci Soc 2014;41:10-5

How to cite this URL:
Bangash A, Khan N, Azeem I, Sadiq M. Technique of clamp-tie thyroidectomy versus Harmonic focus R . Is there a need for technology?. J Sci Soc [serial online] 2014 [cited 2019 Jul 18];41:10-5. Available from: http://www.jscisociety.com/text.asp?2014/41/1/10/126704


  Introduction Top


Goiter was observed by the Romans as their influence extended into Alpine regions and had been depicted by artists for centuries. Anatomical definition of the thyroid awaited Leonardo da Vinci in about 1500 and Andreas Versalius in 1543. The term "thyroid" (Latin: Shield-shaped) is attributed to Bartholemeus Eustacius of Rome while in London Thomas Wharton named it as "glandular thyroidoeis" in his Adenographia in 1656. Frederick Ruysch of Leyden suggested that the gland secreted fluid into the veins and, in the late eighteenth century, Caleb Hillier Parry of Bath who identified exophthalmic goiter in 1786 before Graves' description of 1835, described it as a vascular reservoir to prevent engorgement of the brain. [1]

Early attempts to treat thyroid enlargement and over activity were horrifying and associated with a very high mortality and morbidity due to hemorrhage, asphyxia, hospital gangrene, and air embolism. Technical improvement did not occur until the middle of the nineteenth century. In the interim, appalling results led in 1646 to the imprisonment of a surgeon for his work and to a total ban on the operation by the French Academy of Medicine in 1850. [2] Introduction of thyroidectomy saw a high incidence of morbidity and a modest morbidity, but the work of Theodor Kocher and then William Halsted of Baltimore, Charles Mayo of Rochester and George Crile of Cleveland, Ohio, and subsequently Frank Lahey had revolutionized the safety of thyroidectomy. In 1938 recurrent nerve palsies recorded with incidence as low as 0.3% saw a major shift in concepts. [3],[4]

More interestingly the turn of the 21 st century saw another major shift in trends in thyroid surgery by the introduction of vessel sealing devices. [5],[6] Varying trials comparing the different product commercially available have shown a reduction in operative times and earlier recovery. [7],[8] More accepted versions include Harmonic R and LigaSure R series of shears. [9],[10] To optimize surgery newer designs of shears that include Focus R and Precise R have been introduced. With a modest increase in the price, the safety of surgery cannot be overemphasized neither can the impact of per-operative decrease in blood loss. [11] The later resulting in better delineation of anatomy of recurrent laryngeal nerve and parathyroid gland and a decreased incidence of per-operative complications. [12] The incidence of post-operative superficial hematoma and deep hematoma are other dreadful complications that have been fields of focus for Focus R .

Harmonic devices such as the focus simultaneously cut and coagulate and seal vessels using ultrasonic vibrations at frequencies of 55.5 KHz. With a lower first initializing cost, this product has been seen as a better alternate using a vessel sealing device in thyroid surgery in contrast to the original clamp-tie technique of thyroidectomy. [13] With lesser need to replace the hand instrument and easy maneuvering it makes this shear the best alternate. [14] The rationale of this study having depicted the operative times and lesser frequent complications seen in other studies is without doubt common ground.


  Materials and Methods Top


This interventional (experimental) controlled trial was conducted at Lady Reading Hospital From 11 th June, 2010 to 10 th June, 2012 and included all patients undergoing total thyroidectomy for benign disease i.e., no pre-operative evidence of malignancy. Due to lack of a sample frame non-probability consecutive sampling was carried out and patients were placed into two arms. Group 1 included those patients that underwent total thyroidectomy using the Harmonic Focus R, whereas Group 2 included all those patients that underwent total thyroidectomy by a clamp-tie technique. Following rigid scrutiny a limited number of cases under peer observation were presented with modified operative technique or the so-called hybrid technique, were documented and placed before the ethical review team of the college of physicians and surgeons, Karachi.

From the frequency of complications depicted by other studies in a recent times [17],[18] and for a margin of error at 10%, using the WHO sample size calculator, 120 cases were decided to be part of the study. The aim was to assess: (1) decrease of operative time (min); (2) Decrease of post-operative blood loss (ml); (3) Decrease of post-operative stay (days); decrease of post-operative complications (%, hypocalcaemia, laryngeal nerve damage), compared to traditional dissection in a prospective randomized trial of total thyroidectomy procedures, for benign disease. All the patients were admitted through the out-patient department, following obtaining an informed consent attached to the relevant proforma. The patients were blinded from the sequence of placement in respective arms and were not feasible for blinding of the surgeons due to limitations.

Following admission necessary documentation of the relevant investigations performed via the out-patient department was reassessed by the attending surgeons and at his discretion further advised. Those with a subclinical or overtly evident earlier hyperthyroid state were reassessed following the use of medications. All medications including the use of beta-blockers (10-14 days therapy) and antithyroid agents (3 months therapy) were managed accordingly. None of the patients were given iodine compound at any point perioperatively. Thus, minimal delay foreseen before the placement of patients for the next coming list on an elective basis was observed once the patient was rendered euthyroid.

All patients with preliminary diagnosis of benign disease of the thyroid gland planned for total thyroidectomy were included. Those yielding malignant disease at histopathological report were also maintained and not excluded. All ages between 18 and 60, were included, but clear evidence or Fine Needle Aspiration Cytology (FNAC) suggestive of suspicious malignancy were excluded as were those lost to follow-up.

The operative technique was just as standard or conventional clamp-tie technique with the exception that in Group 1, there was no clamping and also that the dissection was carried out with the same instrument that was the Harmonic Shear Focus R . In both groups, the incision was similar with an extended neck position and sandbag below shoulders. All cases were performed with the standard anesthetic techniques and general anesthesia given. Drain was placed in all cases and fixed through a separate stab incision.

Surgeons allocated to perform were those with a minimum experience of 100 cases of thyroid surgeries performed before this study. They were not blinded from the inclusion of the patient in the study to avoid modification of technique. Post-operatively all patients were maintained in the respective units for 6-12 h in the high dependency units with monitoring of vitals and check on drain. All this data alongside the indication for surgery, first post-operative day calcium levels and the hoarseness (using GRBAS grade), quantity of blood in a drain on first post-operative day.

Having collected all this data on a relevant proforma and further data observed on the improvement of cases of hoarseness over the receding weeks in the out-patient department, statistical data entered. The sequence of skin stitch removal or staple removal was decided accordingly and a 1 week follows-up and 1 month follow-up was planned.

The data following collection was entered onto the SPSS version 16.0 for Windows R and analyzed. The demographic data along with the hospital stay was depicted on histograms. All categorical data were analyzed using the Chi-square test and quantitative data normally distributed was assessed with paired sample t-test and non-normally distributed data were assessed with Mann-Whitney U test. A confidence interval (CI) limit of 95% was maintained from the start of study and thus a P value of 0.05 was considered as significant. Multi-variate analysis was performed for confounding factors namely sex and age.


  Results Top


This study was conducted in the Department of Surgery from June, 2010 to June 2012 at the Lady Reading Hospital, Peshawar. One hundred and twenty patients deemed for alternate (consecutive) placement into two groups for total thyroidectomy by a vessel sealing device and another group by the traditional clamp-tie technique. The demographic data in comparison by the two groups saw no significant difference (P = 0.822). Age ranges were also similar, but late age was not a common finding, whether bias or coincidence cannot be defined as the surgeon was not blinded and case mix was only including total thyroidectomy of which the fair share were endemic cases that was depicted by the pre-operative diagnosis (P = 0.51).

In total 11 male patients were included in the study and following surgery only one patient of all these had histological diagnosis of malignancy. The most common indication in these endemic cases were the patient wishes (and cosmesis) and with bilateral involvement they were counseled for the impending complications with the procedure, but even then 12 patients (10%) in all cases were presentations with respiratory distress diagnosed on pulmonary function tests.

Apart from those details the duration of hospital stay was significantly lower in the group undergoing thyroidectomy by the use of the vessel sealing device. The choice of incision was the same and the need for a section of the sternocleidomastoid muscle was dependent on the individual case, thus accurate judgment on the amount of trauma by surgery in individual cases is hard to predict (P = 0.031) [Table 1].
Table 1: Demographic and post-operative data


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The next most important part was documentation of the duration of surgery and also the amount taken for each side, but this too was lower in Group 1, which was a clear added benefit apart from the need for instrument change. The number of instances of instrument changes was on an average also higher in Group 2 (70.4 ± 8.9) (P = 0.01) this was also significant difference.

Data regarding the use of pre-operative medications and indication varied with a higher incidence of cosmetic cases in Group 1 but the figures are not significant and the study had included all conditions that required total thyroidectomy [Table 1].

The list of complications was long, but the clinically evident were elucidated and fortunately in accordance with the earlier figures from our center, the need to reopen or re-explore was nil. The whole study only one patient that revealed hoarseness persisting beyond 1 month was observed (1.6%). The part of the observation that was intriguing that all the patients in the conventional clamp-tie group carried on being persistently hypocalcemic at the end of 1 month, whereas the Group 1 saw most patients gathering their parathyroid functions shortly after the surgery (P = 0.04) [Table 2].
Table 2: Post-operative complications


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Considering constraints of accurate measurement of the amount of blood loss, hemostasis was a measure as the amount of blood in the drain on the first post-operative day. This was significantly elevated in the conventional clamp-tie thyroidectomy group (P = 0.001). The above variables were all compared for the confounding variables age, sex, diagnosis, and indication, but changed none of the above values.


  Discussion Top


With evidence to support the frequency of complication for thyroid surgeries well below figures in the earlier part of century the need for introduction of technology has shown to make life easier during surgery and safer. [14],[15],[16],[17] The first purpose built shear fitted to a compatible generator for the purpose of thyroid surgery was in 2007. [19] Since then literature has been storming and even yet trials are being undertaken to compare the different commercially available products. [20],[21],[22] These have been out of necessity as clearly the duration of surgery and the frequency of complications are all reduced.

Safety of the procedure had been earlier shown from studies conducted by Miccoli et al. [23] showed reduced operative time by 14 min that was greatly reduced in our study, only marginally greater a difference as compared to their study. In both studies, the statistical evidence proved significant. In his study, the number of ligatures/clips was greatly reduced in the vicinity of the vessels related to the thyroid gland. This detail was not collected in our study, but although earlier study showed a significant difference they numbers were higher in the thyroidectomy performed using an ultrasonic dissector. This could be explained by the reluctance on the part of surgeons to rely purely on the dissector at the main vessels, thus adopting a hybrid technique of first ligating and then using the ultrasonic dissector to complete transection.

To avoid confounding a full sized incision was performed in both groups in our study; thus the calculation of visual analog score would be uniform. In this very earlier study, the length of the incision varied and thus, could have confounded with the visual analogue score averages. Terris et al. [24] had a larger sample of consecutive patients with 216 patients using the same Harmonic R generator but using the Harmonic Ace R instead of the newer shear used in our study. The procedure performed was minimally invasive (minimally invasive video assisted thyroidectomy) in the study by Terris et al. that varies greatly when comparing a 5 cm incision versus a full sized incision for thyroidectomy. There were 154 hemithyroidectomies and 62 total thyroidectomies in the study group. The mean (standard deviation) incision length (available in 182 of 216 patients) was 27.7 (6.6) mm. There were 16 complications (7.4%).

Miccoli et al. [23] had 62 patients included in their study but the sample size calculated for our study was in accordance with conventional technique results as the intervention was still in early days before the beginning of our study. Thus from valid studies providing the frequency of nerve injury, such as the above mentioned the deemed sample would have been much larger than the number of patients included in our study.

Newer shears commercially available also saw Bove et al. [25] compare 240 patients in various groups using the two techniques and use if Ligasure Precise R shear. The difference between the shears compared was in favor of Harmonic Focus R having the shortest mean operative time and a difference of 10 min that was significant (P = 0.019) [Table 3].
Table 3: Comparisons of operative time in studies using ultrasonic shears for thyroidectomy


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In an early meta analytic study conducted by Cirrochi et al. [27] there is a statistically significant reduction of the operative duration (weighted mean difference, −18.74 min; 95% (CI), (−26.97 to -10.52 min) (P = 0.00001).

The indications of cases requiring surgery varied widely between studies and in the study performed by Bove et al. a fair share of the pathology proved histopathologically were malignant. In our study, this confounding variable was excluded with evidence of malignany on FNAC. Those cases that were proved malignant after surgery a later dated neck dissection had no impact on the outcome of the study. Other confounding variables such as sex and age were also tested by multi-variate analysis that did not alter the results shown earlier.

The pain scores in most studies showed a significant reduction in the group of patients that were operated with the ultrasonic dissection. Not evaluated in this study, the logic to consider that such was the cases with little variation of dissection, would result in a modest reduction in the pain scores is to be judgmental. Yet our study does support that category considering the difference in post-operative stay. In our study, this figure was significant with a mean difference of 1.5 days (P = 0.031) this could be a biased observation on behalf of the operating and research team, but blinding at such an early phase of use of the technology should have prompted an increased hospital stay in the Group 1. Whether the dissection performed by the new gadget or the less amount of operative time resulted in the difference remains unresolved.

To no surprise is the fact that reduction in the amount of blood in the drain following 24 h is less in the group operated with Harmonic Focus F . The vessel sealing device promises accurate hemostasis in vessels <5 mm diameter and also eliminating the chance of a slipped ligature or a similar technical error. In the study by Miccoli et al. alone 68 ml was recorded in the drain at the end of 24 h in the conventional clamp-tie group, not comparable to the 35 ml in the Harmonic group (P < 0.05). The amount of blood in the drain was slightly greater than in other studies (P = 0.001). The study did not allow the discretion to avoid a drain in selected cases although the argument has dominated many surgeons to selectively use drain when needed. [27]

The reason to ascertain why the hemostasis is so accurate following the use of the vessel sealing device is multi-factorial. It has excellent handling and fewer changes of instruments that data look so congested cause surgeons less hurried over the fact that any vessel be spared during the dissection. Repeatedly changing instruments can be cumbersome and frustrating that can be the cause for avulsion. Apart from the above, the use of a knot has technical implications (human error) and the device has great control over a section of thyroid tissue that is extremely helpful in lesser than total thyroidectomies.

The frequency of complications was not very different from earlier studies using both techniques and none proved statistical evidence of any difference. [28],[29] The frequency of nerve injury judged by the fact that 240 nerves were at risk of injury, only one nerve supposedly injured that resulted hoarseness beyond the 1 month period (1.6%) comparable to the study by Miccoli et al. where it was 1.4% in the Harmonic Focus R group.

The frequency of transient hypocalcemia was similar to the statistics portrayed in the meta-analytic study of Corrochi et al. and was surprisingly significant between groups for hypocalcemia persisting beyond 1 month suggesting hypoparathyroidism, which was higher in the conventional clamp-tie Technique (P = 0.04).


  Conclusions Top


The use of ultrasonic dissector is safe and significantly reduces operative time. The frequency of hypoparathyroidism inferred from hypocalcemia persisting beyond 1 month was greater in the conventional clamp-tie group as was the amount of blood in the drain at 24 h. The reduced hospital stay suggest that reduced operative times and minimal trauma and handling has better out comes. Quality of life studies and pain chart scores following standardization of methods needs to be evaluated.

 
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