[Prediction of perioperative hyperkalemia in dialysis patients with secondary hyperparathyroidism].

Objective: To explore the influencing factors for serum potassium >4.4 mmol/L in the morning of parathyroidectomy in hemodialysis patients with secondary hyperparathyroidism (SHPT). Methods: The clinical data of 72 patients with SHPT who received regular hemodialysis and underwent parathyroidectomy in Guangdong Provincial People's Hospital from January 2012 to December 2018 were analyzed retrospectively. There were 37 males and 35 females, aged from 25 to 69 years, and the dialysis timespan was from 0.5 to 11 years. The levels of parathyroid hormone, serum potassium and serum calcium before hemodialysis were examined one day before operation, and hemodialysis time and dewatering volume after hemodialysis without heparin were recorded, and also the level of serum potassium in the morning of parathyroidectomy was detected. The occurrences of hyperkalemia during and after operation were studied. The factors related to hyperkalemia in the morning of parathyroidectomy were evaluated by Pearson or Spearman correlation analysis, and the cut-off values of risk factors were calculated by receiver operating characteristic (ROC) curve. Results: Serum potassium >4.4 mmol/L in the morning of parathyroidectomy existed in 23 of 72 patients. Correlation analysis showed that serum potassium one day before operation ((4.93±0.56)mmol/L, r=0.656, P<0.001) and dehydration volume ((2.37±0.75)L, r=0.261, P=0.027) were positively correlated with serum potassium in the morning of parathyroidectomy((4.16±0.54)mmol/L). Serum potassium before hemodialysis one day before operation was a main predictor for serum potassium in the morning of parathyroidectomy (AUC=0.791, P<0.001). The cut-off value of serum potassium before hemodialysis one day before operation was 5.0 mmol/L. Conclusion: Serum potassium before hemodialysis one day before operation in patients with SHPT can predict serum potassium in the morning of parathyroidectomy, offering imformation for the safety of operation.

Higher frequency electrical stimulation enhanced myloglossus satellite cell differentiation by upregulating expression of Pax7 mRNA, MyoD, myogenin and MyHC protein.

OBJECTIVE: We investigated the effect of electrical stimulation (ES) of varying pulse frequency on differentiation and proliferation of canine myloglossus satellite cells in vitro. MATERIALS AND METHODS: Cellular viability and proliferation were assayed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) assay and flow cytometry fluorescence-activated cell sorting analysis. Cellular differentiation and expression of mark molecule were assayed by Real Time-PCR and Western blot. RESULTS: With increasing frequency ES, we found a significant increase in Myod (r=0.988, p<0.0001), myogenin (r=0.988, p<0.0001), MyHC-slow (r=0.988, p<0.0001), MyHC-fast (r=0.875, p<0.0001) protein expression, and Pax7 mRNA expression (r=0.712, p=0.001). CONCLUSIONS: Pax7 mRNA expression and MyoD, myogenin, and MyHC protein expression were increased with increment of electrical stimulation frequency in myloglossus muscle satellite. Higher frequency ES enhanced myloglossus satellite cell differentiation, not proliferation and viability.

[The surgical effectiveness of montgomery thyroplasty implant on patients with unilateral vocal fold paralysis].

Objective: To investigate the efficacy of type I thyroplasty with Montgomery prosthesis implantation for the treatment of unilateral vocal fold paralysis. Methods: From May 2015 to March 2019, 46 patients (24 males, 22 females, with age range of 23-77) with unilateral vocal fold paralysis underwent thyroplasty with Montgomery prosthesis implantation in the Department of Otorhinolaryngology Head and Neck Surgery in both the First Affiliated Hospital of Navy Medical University and Guangdong Provincial People's Hospital. The assessment methods included GRBAS auditory perception assessment, acoustic analysis such as Jitter, Shimmer, NHR and maximum phonation time (MPT). Results: Postoperative videostroboscopy observed the displacement of paralyzed vocal fold to the midline in 44 cases as well as significantly reduced glottic fissures during phonation. In the other 2 cases, glottic fissure did not reduce significantly. Compared with preoperative data, the scores of all parameters in GRBAS auditory perception assessment were lower except the parameter S, and the acoustic analysis parameters (jitter, shimmer, NHR) were smaller, and MPT was longer. All the difference was statistically significant (P<0.001). Revision surgery was performed in 2 patients with poor results. No serious complications occurred in all the cases. Conclusions: For the patients with unilateral vocal fold paralysis who are not suitable for the laryngeal reinnervation surgery due to old age or long course of denervation, thyroplasty with Montgomery prosthesis implantation can effectively improve the voice of patients with high safety,which is worthy of promotion.

[Long term result of arytenoidectomy with CO2 laser for dyspnoea in iatrogenic bilateral vocal fold paralysis patients].

Objective:To investigate the optimal time of tracheotomy/arytenoidectomy and the improvement of dyspnoea, dysphonia and dysphagia after arytenoidectomy with CO2 laser in iatrogenic bilateral vocal folds paralysis patients. Method:Thirty patients [29 females, 56 (49-60) years, one male, 49 years] with bilateral vocal cords paralysis resulted from neck surgery were retrospectively analyzed by case archived information and following-up questionnaire. The data included patients' dysponea time, degree and duration from tracheotomy/arytenoidectomy to neck surgery. Twenty sixty patients required unilateral partial/total arytenoidectomy. The results of treatment were evaluated by questionnaire including dyspnoea, dysphonia and dysphagia. Result:All patients whose bilateral vocal paralysis were resulted from thyroid gland surgery. Dysponea occurred immediately after thyroidectomy surgery in 14 cases (46.7%), and 2 years later after thyroidectomy in 13 cases (43.3%), 8 years later in 3 cases (10.0%). There was one (3.3%) patient without tracheotomy. The duration of tracheotomy/arytenoidectomy to neck surgery was significantly correlated with duration of tracheotomy/arytenoidectomy to dyspnoea appearance (r=0.879, P<0.05), not correlated with duration of thyroid surgery to dyspnoea appearance. There is significantly negative correlation between degree of dyspnoea and duration of tracheotomy/arytenoidectomy to neck surgery (r=0.452, P<0.05). Twenty six patients appeared dyspnoea and underwent CO2 laser arytenoidectomy after thyoidectomy 0.5-23 years. Five patients did unilateral total arytenoidectomy and 21 patients did unilateral partial arytenoidectomy. After 12-96 months following up, dyspnoea improved in 24 patients, no improved in 2 patients. Dysphonia improved and remained in 17 patients, being worse mildly in 8 patients and obviously in one patient. Dysphagia improved and remained in 24 patients, being worse in 2 patients. There was no difference between total and partial arytenoidectomy in dyspnoea, dysphonia and dysphagia. Conclusion:The morbidity of dyspnoea was correlated with time after neck surgery. It was rarely necessary to take tracheotomy immediately in bilateral vocal fords paralysis patients after neck surgery. The severer degree of dyspnoea led to shorter duration between neck surgery and tracheotomy/arytenoidectomy. There was obvious improvement after arytenoidectomy in dyspnoea, no significant change in dysphonia and dysphagia. The effect of total arytenoidectomy on bilateral vocal paralysis was similar to partial arytenoidectomy.

Experimental study on microthrombi and myocardial injuries.

The experiment was conducted with SD male rats. After they had been each given an intravenous injection of high molecular weight dextran (0.8 ml/100 g body wt) once a day for 4 days, they were brought under the observation of ECG and mesentery microcirculation. Microthrombi were found in the venules and capillaries of each rat of the experimental group, while in the microcirculation of the control group rats, no microthrombi were found. No changes were found in the ECGs of the rats (n = 6) in the control group after the injections, while the rats in the subject group all suffered a rise in the S-T segment of ECG, an indication of myocardial injuries. The rise was significantly in positive correlation to the increase in microthrombi in number (r = 0.944, P < 0.01). The erythrocytes of the rats in the subject group clustered to become rouleau-like, and platelets aggregated by tens and hundreds to form microthrombi. Their blood also showed a significant decrease in number of platelets. The degree of platelet aggregation and the scores of the rise on ECG were significantly in positive correlation as shown by the results: y = 20 + 94x, r = 0.94, P < 0.01. The plasma TXB2 of the subject group increased obviously but the change of 6-K-PGF1 alpha in the blood was not significant. The content of plasma TXB2 and the scores that indicated the rise in the S-T segment of the ECG showed significantly a positive correlation by the analysis of linear regression equation: y = 109.997 +/- 116.25x, r = 0.889, P < 0.05. The activity of Na(+)-K(+)-ATPase on the myocardial cell membranes of the rats with microthrombi was significantly reduced as compared with that of the rats in the control group (P < 0.01). The activity of the Na(+)-K(+)-ATPase was significantly in negative correlation to the rise in the S-T segment of ECG (P < 0.05). This study demonstrates that the above changes are the causes of myocardial injuries in rats with circulatory thrombi.