Correction: Cold-Induced Vasodilation during Single Digit Immersion in 0°C and 8°C Water in Men and Women.

[This corrects the article DOI: 10.1371/journal.pone.0122592.].

The Effects of Heat Adaptation on Physiology, Perception and Exercise Performance in the Heat: A Meta-Analysis.

BACKGROUND: Exercise performance and capacity are impaired in hot, compared to temperate, conditions. Heat adaptation (HA) is one intervention commonly adopted to reduce this impairment because it may induce beneficial exercise performance and physiological and perceptual adaptations. A number of investigations have been conducted on HA but, due to large methodological differences, the effectiveness of different HA regimens remain unclear. OBJECTIVES: (1) To quantify the effect of different HA regimens on exercise performance and the physiological and perceptual responses to subsequent heat exposure. (2) To offer practical HA recommendations and suggestions for future HA research based upon a systematic and quantitative synthesis of the literature. DATA SOURCE: PubMed was searched for original research articles published up to, and including, 16 February 2016 using appropriate first- and second-order search terms. STUDY SELECTION: English-language, peer-reviewed, full-text original articles using human participants were reviewed using the four-stage process identified in the PRISMA statement. DATA EXTRACTION: Data for the following variables were obtained from the manuscripts by at least two of the authors: participant sex, maximal oxygen consumption and age; HA duration, frequency, modality, temperature and humidity; exercise performance and capacity; core and skin temperature; heart rate, stroke volume, cardiac output, skin blood flow, sweat onset temperature, body mass loss, sweat rate, perception of thirst, volitional fluid consumption, plasma volume changes; sweat concentrations of sodium, chloride and potassium; aldosterone, arginine vasopressin, heat shock proteins (Hsp), ratings of perceived exertion (RPE) and thermal sensation. DATA GROUPING: Data were divided into three groups based upon the frequency of the HA regimen. Performance and capacity data were also divided into groups based upon the type of HA used. DATA ANALYSES: Hedges' g effect sizes and 95 % confidence intervals were calculated. Correlations were run where appropriate. RESULTS: Ninety-six articles were reviewed. The most common duration was 7-14 days and the most common method of HA was the controlled work-rate approach. HA had a moderately beneficial effect on exercise capacity and performance in the heat irrespective of regimen; however, longer regimens were more effective than shorter approaches. HA had a moderate-to-large beneficial effect on lowering core body temperature before and during exercise, maintaining cardiovascular stability, and improving heat-loss pathways. Data are limited but HA may reduce oxygen consumption during subsequent exercise, improve glycogen sparing, increase the power output at lactate threshold, reduce lactate concentrations during exercise, have a trivial effect on increasing extracellular concentrations of Hsp, and improve perceived ratings of exertion and thermal sensation. CONCLUSION: HA regimens lasting <14 days induce many beneficial physiological and perceptual adaptations to high ambient temperatures, and improve subsequent exercise performance and capacity in the heat; however, the extent of the adaptations is greatest when HA regimens lasting longer than 14 days are adopted. Large methodological differences in the HA literature mean that there is still uncertainty regarding the magnitude and time course of potential adaptation for a number of physiological and perceptual variables.

Cold-induced vasodilation during single digit immersion in 0°C and 8°C water in men and women.

The present study compared the thermal responses of the finger to 0 and 8°C water immersion, two commonly used temperatures for cold-induced vasodilation (CIVD) research. On two separate and counterbalanced occasions 15 male and 15 female participants immersed their index finger in 20°C water for 5 min followed by either 0 or 8°C water for 30 min. Skin temperature, cardiovascular and perceptual data were recorded. Secondary analyses were performed between sexes and comparing 0.5, 1 and 4°C CIVD amplitude thresholds. With a 0.5°C threshold, CIVD waves were more prevalent in 8°C (2 (1-3) than in 0°C (1.5 (0-3)), but the amplitude was lower (4.0 ± 2.3 v 9.2 ± 4.0°C). Mean, minimum and maximum finger temperatures were lower in 0°C during the 30 min immersion, and CIVD onset and peak time occurred later in 0°C. Thermal sensation was lower and pain sensation was higher in 0°C. There were no differences between males and females in any of the physiological or CIVD data with the exception of SBP, which was higher in males. Females reported feeling higher thermal sensations in 8°C and lower pain sensations in 0°C and 8°C compared to males. Fewer CIVD responses were observed when using a 4°C (1 (0-3)) threshold to quantify a CIVD wave compared to using a 1°C (2 (0-3)) or 0.5°C (2 (0-3)) amplitude. In conclusion, both 0 and 8 °C can elicit CIVD but 8°C may be more suitable when looking to optimise the number of CIVD waves while minimising participant discomfort. The CIVD response to water immersion does not appear to be influenced by sex. Researchers should consider the amplitude threshold that was used to determine a CIVD wave when interpreting previous data.

The validity of the SmartJump contact mat.

The aim of this study was to establish the criterion validity of the SmartJump contact mat in assessing vertical jump height (VJH) and peak power (PP). Twenty-three participants (15 men, age = 26 ± 6 years; 8 women, age = 26 ± 9 years) completed a maximal effort vertical jump using 3 different jump types (countermovement jump [CMJ], countermovement with arms [CMJA], and squat jump [SJ]). Data were simultaneously collected on both the contact mat and force platform. Vertical jump height was calculated using the time in air (TIA) method with both force platform (TIA(platform)) and contact mat (TIA(mat)) data and the takeoff velocity (TOV) method using the force platform (TOV(platform)) data. Peak power was calculated using a validated equation. The results showed that VJH and PP calculated using the TIA(mat) method were significantly greater than that calculated from the TIA(platform) and TOV(platform) methods for all jump types (VJH: p < 0.001, PP: p < 0.001). The results from this study show clear discrepancies between apparatus and calculation methods that may have implications for practitioners and should be considered when assessing VJH and PP in the field.

Increasing incidence of thyroid cancer is due to increased pathologic detection.

BACKGROUND: There has been a marked increase in the incidence of thyroid cancer worldwide over recent decades. Patients with retrosternal goiter (RSG) are not picked up generally by common surveillance techniques such as ultrasound. The aim of this project was to study the incidence of thyroid cancer in patients with RSG. METHODS: This is a retrospective cohort study. Documented were patient demographics as well as the size, type, and numbers of thyroid cancers. The number of routine histologic blocks examined for multinodular goiter in the different time periods was also examined. RESULTS: Within a cohort of 13,793 thyroidectomies performed over 40 years, there were 2,260 patients (14%) who underwent surgery for RSG. The percentage of patients with RSG containing thyroid cancer increased from 3.6 to 7.5% (P < .05); however, once papillary microcarcinomas (PMC) (

National Breast Cancer Audit: ductal carcinoma in situ management in Australia and New Zealand.

BACKGROUND: Ductal carcinoma in situ (DCIS) is a significant issue in Australia and New Zealand with rising incidence because of the implementation of mammographic screening. Current information on its natural history is unable to accurately predict progression to invasive cancer. In 2003, the National Breast Cancer Centre in Australia published recommendations for DCIS. In Australia and New Zealand, the National Breast Cancer Audit collects information on DCIS cases. This article will examine these recommendations and provide information from the audit on current DCIS management. METHODS: Three thousand six hundred and twenty-nine cases of DCIS were entered by 274 breast surgeons between January 1998 and December 2004. Data items in the National Breast Cancer Audit database that were covered in the National Breast Cancer Centre recommendations were reviewed. Information was available on the following: diagnostic biopsy rates for all cases and mammographically positive cases and rates of breast conserving surgery (BCS), clear margins following BCS, postoperative radiotherapy following BCS for groups at high risk of recurrence as well as axillary procedures and tamoxifen prescription. RESULTS: Close adherence was found in diagnostic biopsy, BCS and clear margin rates. Some high-risk groups received radiotherapy, although women with 'close' margins did not in 33% of cases. Axillary procedures were conducted in 23% of cases and most (81%) patients were not prescribed tamoxifen. CONCLUSION: There was predominantly close adherence to recommendations with three possible areas of improvement: fewer axillary procedures, an appraisal of radiotherapy practice following BCS and more investigation into tamoxifen prescription practices for DCIS.

National breast cancer audit: overview of invasive breast cancer management.

BACKGROUND: The National Breast Cancer Audit is an initiative of the Breast Section of the Royal Australasian College of Surgeons collecting surgical information in early breast cancer. It is managed in conjunction with the Australian Safety and Efficacy Register of New Interventional Procedures - Surgical. An overview of results for invasive breast cancer from January 1999 until December 2004 is presented to provide preliminary data for participating surgeons. METHODS: Invasive breast cancer cases were retrieved from the National Breast Cancer Audit database for the 274 participating breast surgeons in Australia and New Zealand. Data for a variety of clinical parameters were analysed to provide an overview of the diagnostic, histological, surgical and adjuvant therapy management issues. RESULTS: There were 25,026 cases of invasive breast cancer. Annual percentages of mammographically detected cancers from 1999 to 2004 did not differ significantly. Breast-conserving surgery rates also remained stable at 60%. Margins were involved in 5% of patients; an additional 9% had final margins of less than 1 mm. Radiotherapy followed breast-conserving surgery in most cases (86%). Patients undergoing mastectomy with large tumours (>5 cm) underwent radiotherapy in 71% of cases. When at least four lymph nodes were positive, radiotherapy followed mastectomy in the majority (75%) of cases. The most frequently carried out axillary procedure was a level 2 dissection. Chemotherapy was received by 78% of oestrogen receptor negative, axillary node positive, postmenopausal patients. Tamoxifen was used in the majority (83%) of oestrogen receptor positive cases. CONCLUSION: Surgeons contributing their invasive breast cancer data show a high quality of treatment. Some further improvement may be possibly related to excision margins and tamoxifen prescription for oestrogen receptor negative cancers. Chemotherapy prescription might also warrant further investigation.

Minimal access thyroid surgery: technique and report of the first 25 cases.

BACKGROUND: Minimal access thyroid surgery, using various techniques, is increasingly being reported. The present study reviews our experience with thyroid surgery using a lateral focused mini-incision approach, and assesses its safety and feasibility. METHODS: The study group comprised all patients undergoing minimal access thyroid surgery (MATS) during the period May 2002-May 2003. Data were prospectively gathered, including patient demographics, indication for surgery, operation performed, nodule size, final pathology, and complications. Exclusion criteria for this procedure included: family history of thyroid cancer, previous neck irradiation or surgery, carcinoma on fine needle aspiration, presence of significant thyroiditis, multinodular goitre, and nodule size >3 cm. The operation was carried out through a 2.5-cm lateral incision placed directly over the nodule, with exposure gained by dissecting the plane between the sternomastoid muscle and the lateral edge of the strap muscles. RESULTS: Twenty-five patients underwent MATS, 22 women and three men. Nineteen patients underwent hemithyroidectomy, five underwent isthmectomy, and one underwent local nodule excision. The average measured incision size was 2.63 cm at the end of the procedure. The average nodule size was 2.2 cm, and the average thyroid lobe resected measured 4.7 cm in maximal length. Final pathology revealed benign nodules in 21 patients and four thyroid cancers (two follicular and two papillary). There was one wound infection and two patients had temporary recurrent laryngeal nerve neuropraxia. CONCLUSION: Minimal access thyroid surgery is a safe and feasible alternative to open thyroid surgery in selected cases.

Thyrothymic thyroid rests: incidence and relationship to the thyroid gland.

BACKGROUND: Rests of thyroid tissue within the thyrothymic area are relatively common and might be of clinical importance. The purpose of this study is to define the incidence and anatomy of thyroid tissue located in the line of the thyrothymic ligament, referred to here as "rests." STUDY DESIGN: Prospective descriptive intraoperative evaluation of 100 consecutive thyroid or parathyroid procedures was undertaken to identify the incidence and anatomical location of thyrothymic thyroid rests. Photographs and histologic confirmation of the thyroid remnants were obtained. RESULTS: One hundred eighty sides of the thyroid gland are examined in 100 consecutive patients. Thyroid rests in the thyrothymic area were found in 53 patients, or on 83 separate sides of the thyroid (46%). In patients who had rests identified, 30 (57%) had bilateral rests, with 16 (30%) only on the right, and 7 (13%) only on the left. Eighty percent of identified rests were still attached to the thyroid proper by a pedicle of thyroid tissue but 20% were entirely separate. Most rests were small, with 88% being less than 1 cm in diameter. CONCLUSION: Rests of thyroid tissue within the thyrothymic area, either as entirely separate nodules or as prolongations from the thyroid lobe, are relatively common and might be of clinical importance during thyroid or parathyroid surgery.

Minimal access thyroid surgery: is it feasible, is it appropriate?

BACKGROUND: Reports of minimal access thyroid surgery (MATS) using various techniques have recently appeared. This study examined the feasibility of MATS using either a lateral 'focused' or endoscopically assisted approach. METHODS: The study group comprised all patients undergoing minimally invasive parathyroidectomy (MIP) during the period May 1998 to April 2002 in whom a concomitant thyroid procedure was undertaken. All procedures were performed either through a 2-cm lateral cervical incision (n = 19) or endoscopically (n = 7). RESULTS: Twenty-six patients underwent thyroid surgery, consisting of either local excision of a thyroid nodule (n = 25) or hemi-thyroidectomy (n = 1). In 13 patients the nodule was incidentally discovered, in four patients removal of the parathyroid necessitated partial thyroidectomy, and in nine patients the lesion identified by preoperative parathyroid localization proved to be a thyroid nodule. There were no permanent complications in the study group. Two patients required drainage of a haematoma. The final pathology of all 26 cases revealed benign nodular thyroid disease. CONCLUSION: Thyroid surgery can safely be performed as a minimally invasive procedure. Minimal access thyroid surgery is therefore a feasible option for selected patients. The question remains to be answered as to whether this surgical approach is appropriate treatment for nodular thyroid disease.

Worldwide trends in the surgical treatment of primary hyperparathyroidism in the era of minimally invasive parathyroidectomy.

HYPOTHESIS: Minimally invasive surgery for primary hyperparathyroidism has become an accepted part of endocrine surgical practice worldwide. DESIGN: Survey of members of the International Association of Endocrine Surgeons. SETTING: Clinical practice of endocrine surgeons worldwide. MAIN OUTCOME MEASURES: Numbers of parathyroid procedures performed, types of minimally invasive procedures undertaken, and techniques used to ensure completeness of removal of hyperfunctioning parathyroid tissue as reported by the survey respondents. RESULTS: Of 160 surveys completed, 95 (59%) indicate that the surgeons currently perform minimally invasive parathyroidectomy and use this technique on average for 44% of patients with primary hyperparathyroidism. The most common approach is the focused technique with a small incision, either central or lateral (92% [87 respondents]), followed by a video-assisted technique (22% [21 respondents]), and a true endoscopic technique with gas insufflation (12% [11 respondents]). Techniques used to ensure completeness of resection include the quick intraoperative intact parathyroid hormone assay (68% [65 respondents]), a same-day intact parathyroid hormone assay (17% [16 respondents]), and the nuclear probe (14% [13 respondents]). The number of parathyroidectomies performed worldwide increased from 1727 in 1980 to 6977 in 2000 with the average number per surgeon increasing from 23 in 1980 to 45 in 2000. Geographically, 20 (59%) of 34 surveys from the Americas report the use of minimally invasive parathyroidectomy, 23 (56%) of 41 from the Australasian region, and 34 (49%) of 69 from Europe or the Middle East. CONCLUSIONS: The number of parathyroidectomies performed for primary hyperparathyroidism has increased worldwide over the past 20 years. More than half of the surgeons responding to the survey perform minimally invasive parathyroidectomy, with the most using the focused small-incision technique.

Increase in presentations and procedure rates for hyperparathyroidism in Northern Sydney and New South Wales.

OBJECTIVE: To examine changes in presentation of primary hyperparathyroidism and rates of parathyroidectomy in Northern Sydney (the Northern Sydney Area Heath Service) and New South Wales (NSW). DESIGN: Retrospective case series January 1962 - December 2001 and audit of the NSW Department of Health inpatient database (1993-1999). SETTING: University of Sydney Endocrine Surgical Unit, Royal North Shore Hospital. PARTICIPANTS: 1613 patients undergoing parathyroidectomy during the study period. MAIN OUTCOME MEASURES: Age-standardised parathyroidectomy rates and indications for surgical intervention. RESULTS: The age-standardised rates of parathyroidectomy for primary hyperparathyroidism in women have increased significantly in Northern Sydney from 0.14 cases per 100,000 in 1976 to 7.7 cases per 100,000 in 1996 (P < 0.001). In NSW there has been an increase in parathyroidectomy rates in women from 5.1 cases per 100,000 in 1993 to 12.3 cases per 100,000 in 1998 (P < 0.001). Osteoporosis was the most common overall indication for surgery in Northern Sydney, accounting for 27% of all cases. The proportion of cases presenting with osteoporosis increased significantly from 4% in 1962-1980 to 34% over the past decade (P < 0.001). CONCLUSIONS: The rate of parathyroidectomy procedures has increased markedly in Northern Sydney and in NSW. The investigation of osteoporosis has led to the diagnosis of primary hyperparathyroidism in an increasing proportion of cases and has contributed to the growing surgical referral rates.

Minimally invasive parathyroidectomy using the 'focused' lateral approach. I. Results of the first 100 consecutive cases.

BACKGROUND: A feasibility study of 'focused' minimally invasive parathyroidectomy (MIP) using a lateral approach was commenced in 1999. The aim of the present paper was to evaluate the effectiveness and safety of this procedure in the first 100 consecutive patients. METHODS: This was a prospective, non-randomized case-control study. One hundred consecutive patients with primary hyperparathyroidism (mean age 63.1 years; 74 females, 26 males) who fulfilled the inclusion criteria underwent focused MIP between May 1999 and December 2000. The results for the first and last 50 consecutive patients were compared to see whether they were reflective of a learning curve. The role of intraoperative quick parathyroid hormone (QPTH) estimation was also evaluated. RESULTS: Focused MIP was successfully completed in 93 of 100 patients, with seven conversions. Three (3.2%) of the 93 patients had persistent hyperparathyroidism. Quick PTH was measured in 81 patients and the results were true positive (for cure) in 72 patients, false negative in six patients, true negative in two patients and false positive in one patient. Transient recurrent laryngeal nerve paresis occurred in one patient. During the same time period, open parathyroidectomy was performed in 242 patients. The results were not different between the first and later 50 patients undergoing MIP, nor were the outcomes significantly different from patients undergoing open parathyroidectomy. CONCLUSIONS: Focused MIP is a safe and effective operative approach for appropriately selected patients. Failed procedures were invariably related to shortcomings of the localization studies. Measurement of QPTH, although accurate, is unreliable in the presence of multigland disease.

Minimally invasive parathyroidectomy using the 'focused' lateral approach. II. Surgical technique.

BACKGROUND: This paper describes the technique of minimally invasive parathyroidectomy. The technique is based on a thorough understanding of the anatomy of the fascial planes in neck, the surgical pathology and embryology of parathyroid glands and precise anatomical interpretation of preoperative localization studies. METHODS: Tissue trauma is minimized by using a 2.0 cm incision placed directly over the abnormal parathyroid gland and by removing the adenoma, without compromising the basic endocrine surgical principles of identification and preservation of recurrent laryngeal nerve, avoidance of any capsular breech, and ligation of the vascular pedicle. RESULTS/CONCLUSIONS: With proper patient selection, this technique results in a failure rate of less than 4% and ensures that the incidence of complications, such as recurrent laryngeal nerve injury, remains comparable with that of standard open parathyroidectomy.

Total thyroidectomy is now the preferred option for the surgical management of Graves' disease.

PURPOSE: Subtotal thyroidectomy has been advocated as the standard treatment for Graves' disease because of the possibility of avoiding thyroxine therapy as well as the assumed lower risk of complications compared to total thyroidectomy. However, the long-term results of subtotal thyroidectomy are not as good as they were previously believed to be, as evidenced by the increasing incidence of hypothyroidism. If the risk of complications from total thyroidectomy is no higher,then that procedure offers significant advantages in the surgical management of Graves' disease. The aim of this study therefore was to compare the complication rate of the two procedures in patients with Graves' disease. METHODS: This was a retrospective case control study in a tertiary referral hospital. Information was obtained from an endocrine surgery database over the study period from January 1957 to December 2000. During that period 1246 patients with Graves' disease underwent subtotal thyroidectomy and 119 patients underwent total thyroidectomy. RESULTS: Prior to 1987 total thyroidectomy was rarely if ever performed whereas in the last 12 months total thyroidectomy comprised 95% of all procedures. There was no significant difference in the rate of permanent complications between the two procedures although temporary hypocalcaemia was significantly more common following total thyroidectomy. Permanent hypoparathyroidism resulted in one patient each who underwent total thyroidectomy (0.8%) and subtotal thyroidectomy (0.1%). Permanent recurrent laryngeal nerve palsy occurred in one patient who underwent total thyroidectomy (0.8%) and 5 patients undergoing subtotal thyroidectomy (0.4%). CONCLUSION: Given that subtotal thyroidectomy provides an unpredictable outcome and that the risk of permanent complications is no greater than with total thyroidectomy, there appears little logical reason to continue to recommend subtotal thyroidectomy for the surgical management of Graves' disease. We believe that Graves' disease should join the increasing list of thyroid conditions for which total thyroidectomy is the preferred option.