BLOOD SERUM BIOCHEMICAL CHANGES IN PHYSICALLY CONDITIONED AND UNCONDITIONED SUBJECTS DURING BED REST AND CHRONIC HYPERHYDRATION

1. It has been suggested that prolonged exposure to a rigorous bed rest regimen (hypokinesia) may induce greater serum carbohydrate and electrolyte changes in physically conditioned than unconditional subjects and that chronic hyperhydration may normalize or attenuate the development of these biochemical alterations in physically conditioned subjects. 2. Serum carbohydrate and electrolyte changes were determined in 18 physically healthy male volunteers aged 19-24 years during 30 days of a rigorous bed rest regimen. The subjects were divided into three equal groups. The first group consisted of six unconditioned subjects with VO2 max of 44 mL/kg bodyweight/min, the second group consisted of six conditioned subjects with VO2 max of 69 mL/kg bodyweight/min and the third group consisted of six conditioned subjects with VO2 max of 69 mL/kg bodyweight/min who consumed daily an additional amount of 26 mL water/kg bodyweight and 0.10 mg sodium chloride/kg bodyweight. 3. For the simulation of the hypokinetic effect all volunteers were kept under a rigorous bed rest regimen for 30 days. During the prehypokinetic period of 15 days and during the bed rest period of 30 days the concentrations of cortisol, aldosterone, testosterone, triiodothyronine (T3), thyroxine (total; T4), glucose, potassium, sodium and chloride were determined in blood serum of volunteers. 4. During the bed rest period of 30 days serum carbohydrate and electrolyte changes were more pronounced in physically conditioned than unconditioned hypokinetic subjects. In physically conditioned hyperhydrated subjects serum carbohydrate and electrolyte changes were less pronounced than in physically conditioned and unconditioned hypokinetic subjects.(ABSTRACT TRUNCATED AT 250 WORDS)     

A Case-Series Observation of Sweat Rate Variability in Endurance-Trained Athletes

Adequate fluid replacement during exercise is an important consideration for athletes, however sweat rate (SR) can vary day-to-day. The purpose of this study was to investigate day-to-day variations in SR while performing self-selected exercise sessions to evaluate error in SR estimations in similar temperature conditions. Thirteen endurance-trained athletes completed training sessions in a case-series design 1x/week for a minimum 30 min of running/biking over 24 weeks. Body mass was recorded pre/post-training and corrected for fluid consumption. Data were split into three Wet-Bulb Globe Thermometer (WBGT) conditions: LOW (<10 °C), MOD (10–19.9 °C), HIGH (>20 °C). No significant differences existed in exercise duration, distance, pace, or WBGT for any group (p > 0.07). Significant differences in SR variability occurred for all groups, with average differences of: LOW = 0.15 L/h; MOD = 0.14 L/h; HIGH = 0.16 L/h (p < 0.05). There were no significant differences in mean SR between LOW-MOD (p > 0.9), but significant differences between LOW-HIGH and MOD-HIGH (p < 0.03). The assessment of SR can provide useful data for determining hydration strategies. The significant differences in SR within each temperature range indicates a single assessment may not accurately represent an individual’s typical SR even in similar environmental conditions.     

等渗与低渗对比剂在冠心病介入治疗中对肾功能影响的研究

目的 对比评估等渗与低渗对比剂在冠心病介入治疗中对肾功的影响.方法 将2012年6月至2013年1月在西南医院心血管内科住院并诊断为冠状动脉粥样硬化性心脏病,行经皮冠状动脉介入治疗(percutaneous coronary intervention,PCI)的409例患者分为等渗对比剂组(195例)和低渗对比剂组(214例),分别于PCI术前及术后24、72 h留取血尿标本,检测血清肌酐、尿素氮、胱抑素C、尿酸、β2微球蛋白和尿微量白蛋白、尿β2微球蛋白,观察2组患者使用对比剂后急性肾损伤(contrast-induced acute kidney injury,CI-AKI)的发生情况.结果 PCI术后72 h低渗对比剂组血清肌酐及β2微球蛋白均较术前显著升高(P＜0.05),而等渗对比剂组与术前比较则无显著改变(P＞0.05).低渗对比剂组术后24 h尿β2微球蛋白的升高有统计学差异(P＜0.05).共有20例(4.89％)患者符合CI-AKI诊断标准,其中低渗对比剂组17例(7.94％),等渗对比组3例(1.54％),两组间比较差异显著(P＜0.01).PCI前有慢性肾功能不全者经水化治疗,PCI术后各项指标均较术前无显著变化(P＞0.05).结论 在PCI术中使用大剂量对比剂可导致不同程度CI-AKI发生,其中低渗对比剂致CI-AKI发生率显著高于等渗对比剂.     

The effect of athletes` hyperhydration on the urinary ‘steroid profile’ markers in doping control analysis

The urinary ‘steroid profile’ in doping control analysis is a powerful tool aimed at detecting intra‐individual deviations related to the abuse of endogenous steroids. Factors altering the steroid profile include, among others, the excessive fluid intake leading to low endogenous steroids concentrations compared to an individual's normal values. Cases report the use of hyperhydration by athletes as a masking method during anti‐doping urine sample collection. Seven healthy physically active non‐smoking Caucasian males were examined for a 72‐hour period using water and a commercial sports drink as hyperhydration agents (20 mL/kg body weight). Urine samples were collected and analyzed according to World Anti‐Doping Agency (WADA) technical documents. Although, significant differences were observed on the endogenous steroid concentrations under the studied hyperhydration conditions, specific gravity adjustment based on a reference value of 1.020 can eliminate the dilution induced effect. Adjustment methods based on creatinine and urinary flow rate were also examined; however, specific gravity was the optimum method in terms of effectiveness to adjust concentrations close to the baseline steroid profile and practicability. No significant effect on the urinary steroid ratios was observed with variability values within 30% of the mean for the majority of data. Furthermore, no masking on the detection ability of endogenous steroids was observed due to hyperhydration. It can be concluded that any deviation on the endogenous steroid concentrations due to excessive fluid intake can be compensated by the specific gravity adjustment and therefore, hyperhydration is not effective as a masking method on the detection of the abuse of endogenous steroids.     

Effects of Glycerol and Creatine Hyperhydration on Doping-Relevant Blood Parameters

Glycerol is prohibited as an ergogenic aid by the World Anti-Doping Agency (WADA) due to the potential for its plasma expansion properties to have masking effects. However, the scientific basis of the inclusion of Gly as a “masking agent” remains inconclusive. The purpose of this study was to determine the effects of a hyperhydrating supplement containing Gly on doping-relevant blood parameters. Nine trained males ingested a hyperhydrating mixture twice per day for 7 days containing 1.0 g·kg⁻¹ body mass (BM) of Gly, 10.0 g of creatine and 75.0 g of glucose. Blood samples were collected and total hemoglobin (Hb) mass determined using the optimized carbon monoxide (CO) rebreathing method pre- and post-supplementation. BM and total body water (TBW) increased significantly following supplementation by 1.1 ± 1.2 and 1.0 ± 1.2 L (BM, P < 0.01; TBW, P <0.01), respectively. This hyperhydration did not significantly alter plasma volume or any of the doping-relevant blood parameters (e.g., hematocrit, Hb, reticulocytes and total Hb-mass) even when Gly was clearly detectable in urine samples. In conclusion, this study shows that supplementation with hyperhydrating solution containing Gly for 7 days does not significantly alter doping-relevant blood parameters.     

The preference for warm drinking water induces hyperhydration in heat-stressed lactating goats

The aim of this study was to determine whether lactating goats regulate their water intake when given a choice between warm (35 °C) and cold (15 °C) water. Six lactating goats were kept individually in pens. At 07.00 h one bucket was filled with warm water and another with cold water. Water consumption was measured at intervals until 18.00 h. Water temperature was not controlled at night. Two experiments were made, one at normal room temperature (18–19 °C) and the other at 39–40 °C from 10.45 to 17.00 h. At normal room temperature the goats drank 6.0±1.4 L of the warm water but only 1.7±1.3 L of the cold water (P<0.001). The total water consumption, including the following night, was 9.2±1.6 L. This differed from control days, when only cold water was available (5.9±0.4 L; P<0.05). Neither the plasma Na concentration nor the osmolality changed, which indicate that the goats regulated their fluid balance. In the experiments involving heat stress the goats drank 11.5±1.7 L of the warm water but only 2.0±1.0 L of the cold water (P<0.001). In total, including the following night, they drank 16.2±2.6 L (P<0.001 vs. control days). Goats drank repeatedly despite falling plasma Na and osmolality, proving that their thirst was not induced by water losses. Their abdomens became distended, indicating that water was stored in the reticulo-rumen and explaining why their body weights increased. The goats appeared distressed. It is concluded that goats prefer to drink warm water. Nevertheless, our results suggest that, if possible, warm drinking water should not be given to lactating goats under hot ambient conditions.     

Pre-Exercise Hyperhydration-Induced Bodyweight Gain Does Not Alter Prolonged Treadmill Running Time-Trial Performance in Warm Ambient Conditions

This study compared the effect of pre-exercise hyperhydration (PEH) and pre-exercise euhydration (PEE) upon treadmill running time-trial (TT) performance in the heat. Six highly trained runners or triathletes underwent two 18 km TT runs (~28 °C, 25%–30% RH) on a motorized treadmill, in a randomized, crossover fashion, while being euhydrated or after hyperhydration with 26 mL/kg bodyweight (BW) of a 130 mmol/L sodium solution. Subjects then ran four successive 4.5 km blocks alternating between 2.5 km at 1% and 2 km at 6% gradient, while drinking a total of 7 mL/kg BW of a 6% sports drink solution (Gatorade, USA). PEH increased BW by 1.00 ± 0.34 kg (P < 0.01) and, compared with PEE, reduced BW loss from 3.1% ± 0.3% (EUH) to 1.4% ± 0.4% (HYP) (P < 0.01) during exercise. Running TT time did not differ between groups (PEH: 85.6 ± 11.6 min; PEE: 85.3 ± 9.6 min, P = 0.82). Heart rate (5 ± 1 beats/min) and rectal (0.3 ± 0.1 °C) and body (0.2 ± 0.1 °C) temperatures of PEE were higher than those of PEH (P < 0.05). There was no significant difference in abdominal discomfort and perceived exertion or heat stress between groups. Our results suggest that pre-exercise sodium-induced hyperhydration of a magnitude of 1 L does not alter 80–90 min running TT performance under warm conditions in highly-trained runners drinking ~500 mL sports drink during exercise.     

宫腔镜电切术过度水化综合征5例临床分析

目的探讨宫腔镜电切术过度水化综合征(TURP综合征)的发生原因、诊断、处理和预防措施。方法对2000年1月~2003年12月中宫腔镜电切术发生过度水化综合征的5例患者进行临床分析。结果子宫肌瘤电切术3例,肌瘤直径>5 cm,均为内凸型,约2/5位于肌壁内,术中肌层破坏面积大;子宫内膜电切术1例,因患者子宫过度后屈,宫腔深达9.5 cm,手术难度大,内膜创面广;宫腔重度粘连电切术1例,宫腔重度肌性粘连,分离后大量血管暴露,创面大。5例经补钠、利尿处理后,症状均得到控制。结论过度水化综合征的发生与复杂的宫腔操作导致的子宫内膜、肌层的破坏程度有关。早期诊断治疗,预后良好。而缩短手术时间,控制宫腔压力,减少灌流液的吸收则是预防其发生的关键。     

预防宫腔镜手术并发过度水化综合征的护理策略

目的:探讨运用创新护理模式预防宫腔镜手术并发水中毒的策略。方法:对400例行宫腔镜电切手术的护理配合进行总结、分析并制定护理方案。结果:减少手术并发症,保障手术顺利进行。结论:通过400例临床患者资料分析,总结临床护理经验,创新护理模式,科学制定护理方案,可以很大程度上降低宫腔镜手术风险,临床值得应用改进和推广。