Can the prophylactic administration of tranexamic acid reduce the blood loss after robotic-assisted radical prostatectomy? Robotic Assisted Radical Prostatectomy with tranEXamic acid (RARPEX): study protocol for a randomized controlled trial

Background

The prophylactic administration of tranexamic acid reduces blood loss during procedures at high risk of perioperative bleeding. Several studies in cardiac surgery and orthopedics confirmed this finding. The aim of this prospective, double-blind, randomized study is to evaluate the effect of tranexamic acid on peri-and postoperative blood loss and on the incidence and severity of complications.

Methods/design

Based on the results of our pilot study, we decided to conduct this prospective, double-blind, randomized trial to confirm the preliminary data. The primary endpoint is to analyze the effect of tranexamic acid on perioperative and postoperative blood loss (decrease in hemoglobin levels) in robotic-assisted radical prostatectomy. The additional endpoint is to analyze the effect of tranexamic acid on postoperative complications and confirm the safety of tranexamic acid in robotic-assisted radical prostatectomy.

Discussion

No study to date has tested the prophylactic administration of tranexamic acid at the beginning of robotic-assisted radical prostatectomy. This study is designed to answer the question of whether the administration of tranexamic acid might lower the blood loss after the procedure or increase the rate and severity of complications.

Trial registration

ClinicalTrials.gov NCT04319614. Registered on 25 March 2020

Colloid Osmotic Pressure Participates on the Post-transplant Lymphocele Pathogenesis

The aim of the study was to evaluate the role of colloid osmotic pressure in post-transplant lymphocele pathogenesis. We have analyzed total plasmatic protein and albumin levels, and electrophoresis has been completed in blood samples before transplantation and in days 3 and 14 after transplantation in 50 patients with lymphocele (Lymphocele) and 198 patients without lymphocele (control), respectively. Colloid osmotic pressure (COP) was calculated according to the Hoefs formula. Statistically significant differences were confirmed in albumin levels (42.2 respectively 44.8 g/L) before transplantation (day 0); in total protein (52.5 resp. 55.5 g/L), in albumin (30.1 resp. 32.1 g/L), and COP (15.6 respectively 17.7 kPa) in day 3; and in total protein (52.8 resp. 58.9 g/L), in albumin (30.5 respectively 35.4 g/L), in COP (16.1 respectively 21.2 kPa) in day 14. A potentially critical albumin level was established in 44.1 g/L in the blood analyzed, but its sensitivity was only 62%. The main risk element for the lymphocele formation remains the surgeon's hand. We can proclaim the role of proteins and their COP in the post-transplant lymphocele formation as one of possible pathogenetic cofactors. It is responsible for the impaired mechanisms of the reabsorption the lymph back to the tissues. Better metabolic care could help to reduce incidence of this surgical complication.

[Biochemic evidence of the presence of urine in a drain following surgery]

OBJECTIVE

Evaluation of the laboratory investigations of the postoperative wound drains liquids containing urine and establishing the borderline levels for confirmation of the urine presence. PATIENTS GROUP AND THE METHODS: Biochemical analysis of the drain liquids, urine and blood serum from the 34 patients with confirmed urine leak out of the urinary tract. The urea, creatinine, natrium, potassium and chloride levels were measured in all samples.

RESULTS

The mean natrium, potassium, chlorides, urea and creatinine mean levels were 93.8 mmol/l, 15.9 mmol/l, 77.0 mmol/l, 73.3.

[Five-year follow up in patients after surgery for clear cell renal carcinoma]

OBJECTIVE

Evaluation of the five-year follow-up of patients treated for clear-cell renal carcinoma in dependency on its characteristic and extension. PATIENTS' COHORT AND METHODS: Retrospective analysis of five-year follow-up of 269 patients treated for clear-cell renal carcinoma in dependency on T, N, M and clinical tumor stage; presence of lymphatic and distant metastases, cellular grade and tumor necrosis. Tumor-specific surviving is presented on Kaplan-Meier curves.

RESULTS

Five-year patients surviving with tumor T1, T2 and T3 were 91.8%, 70.7% and 34.6% respectively. Surviving patients without lymphatic metastases was 85%; with metastases was 6.9%. Surviving patients without distant metastases was 84.1%; with metastases was 0%. Surviving of patients with clinical tumor stage I, II, III and IV were 94.6%, 83.8%, 48.7% and 0% respectively. Surviving of patients with tumor cellular grade G1, G2, G3 and G4 were 87.5%, 95.5%, 64.2% and 27.6% respectively. Surviving patients without tumor necrosis was 92.4%; with metastases was 31.9%.

CONCLUSION

Tumor size and the presence of metastases are very significant factors to patient survival. Histological characteristics as a nuclear grade and a tumor necrosis have been important prognostic factors for the future of the patient. Early diagnosis and aggressive surgical treatment are the most important for the positive course of the disease.

Gas chromatographic analysis of amino acid enantiomers in Carbetocin peptide hydrolysates after fast derivatization with pentafluoropropyl chloroformate

A novel sample preparation protocol for gas chromatographic (GC) analysis of amino acid enantiomers in peptides was developed. It comprises traditional acid hydrolysis, a novel treatment of the analytes with a fluoroalkyl chloroformate and GC/FID separation of enantiomers on a chiral capillary column. The major improvements consist in that the derivatization step proceeds in organic-aqueous media within seconds and the amino acid derivatives are volatile enough to suit the temperature range of the chiral Chirasil-Val capillary column. The approach was found beneficial for chiral analysis of pharmaceutically important Carbetocin peptide.

[Dacryolithiasis--analysis of 15 cases]

Dacryoliths are found in 15-20% patients subject to dacryocystorhinostomy. Dacryoliths are formed by proteins or calcium and phosphate salts. In the development or dacryolithiasis participates chronic inflammation of the sac, it is found more frequently in women where some part is played by the structure of the lacrimal duct, hormonal influence and the use of cosmetic preparations. A typical sign of the disease in the variability of complaints and results of clinical examinations. Assessment of the diagnosis before surgery can be facilitated by dacryocystography. The method of choice in dacryolithiasis is dacryocystorhinostomy. The authors present their own group of 16 dacryolithis which they observed 10x in women and 5x men. The concrements were examined by the method of infrared spectroscopy and gas chromatography. All were formed by proteins; calcium and phosphate salts were not found In all patients after dacryocystorhinostomy the complaints disappeared.

Brain maldevelopment and neurobehavioural deviations in adult rats treated neonatally with indomethacin

The risk of neurodevelopmental toxicity was studied in indomethacin (INDO), an inhibitor of prostaglandin synthesis, which is used in at-risk neonates to prevent the consequences of brain intraventricular haemorrhage or to accelerate the closure of patent ductus arteriosus. Model experiments were carried out in rats of the Wistar strain and Konárovice breed. The drug dose (2 mg/kg, s.c.) was applied to rat pups either once or twice in the following way: (1) on postnatal day 4 (PD:4) or postnatal days 4 and 5 (PD:4-5), i.e. model of brain ontogenic developmental stage in human fetus/preterm neonate of 7-month-gestational age; (2) on postnatal day 9 (PD:9) or postnatal days 9-10 (PD:9-10), i.e. model of brain ontogenic stage in full-term human newborn. The rats were followed up during development (body weight, maturation) until adulthood (age 3-9 months) using tests of behaviour (open field, social memory), nociception (tail flick, plantar test), reproduction and brain neurobiological analysis. The results were evaluated by comparison of litter-mates: treated vs control. No differences between INDO and controls were found in developmental landmarks, adult social memory or reproduction. The pattern of behavioural and neuroendocrine deviations in adult animals was dependent on the ontogenic stage exposed to drug insult. INDO rats of the groups PD:4 and PD:4-5 revealed depression of open field motor activity and emotional reactivity, and higher pituitary weight with lower TSH content. On the other hand, deviations in adult INDO groups PD:9 and PD:9-10 were characterized by pain hypersensitivity, lower pituitary weight with unchanged TSH content and deficit of monoamine transmission in the hypothalamus.

Neuro-immuno-teratogenicity of drugs used in neonatal pharmacotherapy in relation to the ontogenic stage at the time of their administration

The risk of functional teratogenicity of two drugs used in neonatal pharmacotherapy was studied: indomethacin (INDO) and dexamethasone (DEX). Model experiments were carried out in Wistar strain rats, breed Konárovice, which received single subcutaneous drug injection (INDO 2 mg/kg, DEX 1 mg/kg) on postnatal day 4 (PD:4; model of human fetus/preterm newborn of 6-7-month-gestational age) or on postnatal day 9 (PD:9; model of full-term human neonate). The rats were followed up during development (body weight, maturation) till late adulthood (age 6-8 months) using tests of cognition, immune reactivity and biochemical brain analysis. The results evaluated by comparing treated and control litter-mates indicated that the functional teratogenic risk was significantly higher in DEX than in INDO. DEX-rats revealed disorganization of developmental processes: retardation of body growth, but acceleration of sensory development (pinna and eye opening), retarded male sexual maturation. Adult DEX-rats (age 6 months) of both series (PD:4, PD:9) had deficit of short-term memory (social recognition test). Disturbances of immune reactivity (decrease of humoral and rise of cell-mediated immune response) appeared both in adult INDO and DEX-rats (age 7 months), but only in the PD:9 series i.e. when the drugs were administered at a higher stage of the ontogenic development simulating neonatal period in humans. This finding may be warning from the clinical point of view for the neonatological practice.

Chloroformates in gas chromatography as general purpose derivatizing agents

Chloroformates with simplest alkyls, i.e. methyl, ethyl or isobutyl, already known as favourable reagents for treating amino groups in gas chromatography for years, were revealed randomly as exceptionally rapid esterification agents. Unlike the rather poor results achieved with chloroformate-mediated ester formation in organic chemistry, the pyridine-catalyzed esterification of carboxylic acids appeared to proceed at the analytical microscale smoothly. Along with the catalyzer, an alcohol should also be present in the medium, accompanied by acetonitrile or water, according to the character of the compounds treated. Reaction conditions were optimized for various classes of carboxylic acids and a uniquely rapid derivatization of amino acids in aqueous ethanol was shown to be possible. Most of the analytes, e.g. acidic metabolites in physiological fluids, could be treated directly in the aqueous matrix. A simultaneous analysis of, e.g., amino and fatty acids or amines and their acidic catabolytes was proven to be possible. Along with the low-molecular-mass reagents, still some others, i.e. the hexyl, menthyl or pentafluorobenzyl ones, found their application fields. Results of optimized reaction conditions and a wide range of applications of chloroformate-mediated derivatization in various disciplines have been summarized in this review.

Simple approach for analysis of plasma oxo-, hydroxy- and dicarboxylic acids

Following deproteinization of plasma with organic solvents the supernatant was shaken with hexane and cation-exchange resin in an Eppendorf tube to remove fatty and amino acids and the medium was subjected to direct treatment with ethyl chloroformate under catalytic influence of pyridine. A subsequent extraction of the immediately formed ethyl esters with a drop of chloroform enabled us to subject the sample to gas chromatographic (GC) analysis. Since ketocarboxylic acids do not require a preliminary oximation the total time of sample workup and analysis takes only several minutes.

Simultaneous profile analysis of plasma amino and organic acids by capillary gas chromatography

A simultaneous GC analysis of more than 20 amino and nearly 30 non-amino organic acids abundant in plasma is for the first time possible. Isolation of the analytes from the plasma matrix is not necessary, keto acids do not require a preliminary oximation. An instantaneous derivatization of the acids with ethyl chloroformate takes place directly in the medium after deproteinization. Less than 30 min are required to prepare a plasma sample for the GC analysis.

[Perinatal pharmacotherapy and the risk of functional teratogenic defects]

Perinatal period, which is characterized by intensive histogenesis and cytodifferentiation of the already shaped organs, is a highly vulnerable phase for fetal/neonatal brain and immune system-organs with high similarity in receptor equipment. Even fine deviations in the programmed developmental processes induced by drugs initiate disorders in the formation of neural network, cytoarchitectonics and receptor-transmitter communication systems. This pathology is not evident at birth, but forms the basis for various functional defects of neuro-psycho-immunocompetence which become apparent gradually during further maturation or even in adulthood. Clinical recognition of such functional teratogenic action of drugs is hampered by the long time interval (upto decades) between the drug administration and its consequences, making the identification of causal relations very difficult. Consequently, experimental research is necessary under the precondition of adequate animal models with sufficient validity for the extrapolation on human level. The authors suggest the principles of such approach using drug application in neonatal rats with lifelong follow-up of behaviour, immune reactivity and brain biochemical analysis. The evaluation of functional teratogenic risk in three drugs used in the treatment of risk pregnancies and risk neonates (dexamethazone, fenoterol, diazepam) is presented.

Separation of selenium analogues of sulphur-containing amino acids by high-performance liquid chromatography and high-resolution gas chromatography

The historically conditioned adaptation of living organisms to chemically corresponding elements is influenced in nature by anthropogenic activities in many regions, the selenium-sulphur pair being one example of such a case. The separation of selenomethionine, selenoethionine and selenocystine was studied by HPLC and high-resolution GC. Ion-exchange chromatography followed by temperature-programmed GC gives the possibility of the analytical separation of trace amounts of selenomethionine in a complex mixture of common amino acids. Diastereoisomers of selenocystine were identified by HPLC in the AccQ-Tag mode.

Organic acid profiling by direct treatment of deproteinized plasma with ethyl chloroformate

Carboxylic acids in plasma or serum can be conveniently determined by capillary gas chromatography (GC) following treatment with ethyl chloroformate (ECF). The mixed organic solvent used for plasma deproteinization is also suitable as medium for the subsequent reaction step. Thus, isolation of the compounds of interest is not necessary. Before treatment of the supernatant with ECF, the neutral lipids and amino acids are removed easily by hexane extraction and cation-exchange chromatography. Ketocarboxylic acids do not require a preliminary oximation. Capillary columns with a length of 15 m and a polar silicone phase proved to be ideal for the separation of mixtures of derivatized keto-, hydroxy-, mono- and dicarboxylic acids. The run time is less than 30 min.

Adrenergic overactivity and insulin resistance in nonobese hereditary hypertriglyceridemic rats

Nonobese, hereditary hypertriglyceridemic (HTG) rats provide an interesting model of hypertriglyceridemia, glucose intolerance, and hypertension. In age-matched 15 HTG and 16 control Wistar rats fed on a high sucrose diet (70 cal%) for 6 weeks, we measured insulin sensitivity in vivo and some parameters of sympatoadrenal system. Using euglycemic clamps with administration of 2-deoxy[1-3H]glucose, we found whole body insulin resistance and decreased glucose metabolic index Rg' in soleus muscle, epitrochlearis muscle, diaphragm, and white adipose tissue in HTG rats. We found higher levels of plasma epinephrine and higher excretion of vanilmandelic and homovanilic acids in HTG rats. The binding of [3H]-dihydroalprenol to the heart membrane fraction was similar in both groups, but the dissociation constant Kd was increased by 75% in the heart of HTG rats.

Long-chain fatty acids esterified by action of alkyl chloroformates and analysed by capillary gas chromatography

Long-chain fatty acids can be instantaneously converted into methyl, ethyl or chloroethyl esters by the action of corresponding alkyl chloroformates. The reaction is catalysed by pyridine and proceeds in acetonitrile in the presence of a small amount of the corresponding alcohol. The reproducibility is high and the yield exceeds 95%.

Characterization of N-ethoxycarbonyl ethyl esters of amino acids by mass spectrometry

Derivatization of amino acids by using ethyl chloroformate-ethanol-pyridine provides volatile products, N-ethoxycarbonyl amino acid ethyl esters (ECEEs), which are easily amenable to GC or GC-MS analysis. MS behavior of these compounds under electron-impact has been studied. The fragments observed in the spectra facilitate recognition of commonly occurring protein amino acids and characterization of unknown analogues.

Vasoconstrictor reaction to prostaglandins E1 and E2 in the isolated rat hindlimb mediated through serotonin release

The vasoconstrictor effects of prostaglandins E (PGEs) were studied in the isolated perfused hindlimbs of the rat. Doses of PGE1 in the range of 0.01-10 micrograms caused dose-dependent increases in perfusion pressure with rapid development of tachyphylaxis. The pressure increases were inversely temperature-dependent, being 4.8 +/- 1.2 mm Hg at 37 degrees C and 22.2 +/- 1.8 mm Hg at 27 degrees C. The vasoconstriction was limited to PGE1 and PGE2. Other prostaglandins tested, PGF2 alpha, PGD2, PGA1, 7-oxo-PGI2 and arachidonic acid, were without any effect at 27 degrees C. Increased serotonin concentrations were found in the effluent after the administration of 1 microgram of PGE1. The pressor response to PGE1 was blocked by 5-HT2 antagonists, ketanserin (2 micrograms) and naftidrofuryl (100 micrograms), while the alpha-adrenoceptor antagonist phentolamine (6.7 micrograms) was without effect. Rapid tachyphylaxis of the development of vasoconstriction was observed after the repeated administration of PGE1 and PGE2. PGE1 (1 microgram) induced desensitization with more than 60 min duration. All the findings suggest that serotonin was liberated in the rat hindlimbs by PGEs.

[Increased levels of noradrenaline in hypothyroidism and its association with cardiovascular system function]

In a group of 10 athyroid subjects treated with thyroxine and triiodothyronine discontinuation of both hormones induced hypothyroidism. During its development on the 7th, 14th, 21st and 28th day systolic time intervals, the heart rate, blood pressure and noradrenaline and adrenaline plasma level were assessed. On the 7th day of hypothyroidism an increased index of the preejection time was recorded, and its value continued to rise throughout the investigation period. A reduction of the index value of the ejection time was also observed on the 7th day and during the subsequent period the value did not change any more. A decline of the heart rate was observed on the 7th day and subsequently the frequency was stable. The index of electromechanical systole was protracted on the 28th day. The systolic blood pressure declined on the 14th day and did not change afterwards. The diastolic pressure rose on the 28th day. The noradrenaline plasma level was elevated from the 21st day of hypothyroidism, the adrenaline level did not change during the decline of thyroid function. The authors discuss the mutual relationship of changes and evaluate the impact of the rise of the noradrenaline level in hypothyroid subjects.

The hypertriglyceridemic rat as a genetic model of hypertension and diabetes

Hypertriglyceridemia was demonstrated in untreated hypertensive patients as well as in animals with genetic and experimental hypertension. The main purpose of the present study was to evaluate the possibility to use the hereditary hypertriglyceridemic (HTG) nonobese rats in hypertensive research. Direct measurement of blood pressure demonstrated significantly higher systolic, diastolic and mean arterial pressures in HTG rats in comparison with control Wistar rats. There was significant positive correlation between blood pressure and plasma triglyceride concentration (r = 0.585, n = 40, p less than 0.001). In addition, there were significantly increased plasma norepinephrine and epinephrine concentrations in HTG rats, suggesting that the stimulation of sympathetic nervous system could be one of the pathogenetic mechanisms involved in the increase of blood pressure of HTG rats.

[The value of the carbohydrate metabolism response for assessment of early prognosis in patients with acute myocardial infarct without previously detected diabetes]

The authors examined 68 patients with a acute myocardial infarction without previously detected diabetes. They evaluated the importance of the relationship of the intensity of the stressor, humoral stress response and the response of the carbohydrate metabolism for the early prognosis of the infarction. Despite the complexity of these relations and heterogenity in the group of these patients, the authors confirmed the prognostic importance of hyperglycaemia, cortisolaemia and urinary catecholamine levels, and based on their own experience, they recommended to follow up these indicators during the first days after development of the infarction.

[The carbohydrate metabolism and stress hormone response during acute myocardial infarct in persons without diagnosed diabetes]

The authors examined 68 patients with a acute myocardial infarction without previously detected diabetes. They evaluated some indicators of the humoral stress response and the response of the carbohydrate metabolism during a recent infarction. They found very complicated interrelations between hormones of the stress reaction and indicators of the carbohydrate metabolism under conditions of circulatory stress. Despite this they detected some dominating trend and compared their findings with data from the literature.

[Cardiac function and adrenergic regulation in incipient hypothyroidism]

In patients with thyroid carcinoma who after thyroid elimination took thyroxine and triiodothyronine both hormones were discontinued and after 7 days a complex of peripheral and laboratory parameters was evaluated. Discontinuation of thyroid hormones led to a drop of their serum level and concurrent rise of the TSH level and serum cholesterol. The duration of the pre-ejection period of the systole, the Q-Kd interval and Achilles tendon reflex was protracted. The value of the index of the preejection time increased and that of the index of the expulsion time declined. The heart rate and systolic pressure declined and the body eight increased. Seven-day discontinuation of thyroid hormones did not affect the plasma level of noradrenaline, adrenaline and cyclic adenosine monophosphate. The diastolic pressure and index of electromechanical systole did not change.

Sexual differences in serum free amino acid levels in thyropathies

Changes in serum free amino acid level with respect to sex and thyroid function are described. In euthyroid men, the amount of total, glucogenic, essential and nonessential amino acids is significantly higher than in euthyroid women. Patients with thyrotoxicosis exhibited increased levels of all main groups of free amino acids in blood serum. However, the sex-related differences in the main amino acids groups disappeared. The hypothyroidism was also accompanied by the disappearance of the sexual differences between the individual amino acids. The content of essential amino acids declined both in hypothyroid males and females. The participation of metabolic alterations of androgens and estrogens accompanying thyropathies in the genesis of sex-linked amino acid changes is discussed.

Changes of essential amino acids in thyropathies

Composition of free amino acids in serum of patients with thyrotoxicosis and hypothyroidism was studied by gas chromatography. In thyrotoxicosis the level of serum amino acids, especially the essential ones and several glucogenic amino acids, increased. The reverse was found to a lesser extent in hypothyroidism. Thyrotoxicosis exerted an increase and hypothyroidism a decrease in the value of the ratio of the sum of all essential amino acids versus the sum of all nonessential amino acids. The elevation of glucogenic amino acids in thyrotoxicosis is discussed with respect to hepatic function and amino acid mobilization and transport.

Mass spectra of alpha-amino acid oxazolidinones

2-Bis-(chlorodifluoromethyl)-4-substituted-1,3-oxazolidin-5-ones, a new type of alpha-amino acid derivative for gas chromatographic separation, have been studied by low resolution mass spectrometry. These derivatives are obtained by reacting alpha-amino acids with dichlorotetrafluoroacetone. Their structure has been established or confirmed for most protein amino acids and several non-protein alpha-amino acids. The mechanisms responsible for the mass spectral pattern have been rationalized. An interesting feature of this derivatization procedure is that it distinguishes aspartic and glutamic acid from the respective amides. The structure of asparagine and glutamine derivatives has been established. A survey of oxazolidinone mass spectra has provided a list of diagnostically useful ions. Each amino acid can be identified by one or two of its most abundant fragments.

Rapid and effective separation of thyroid hormones and iodide by thin-layer chromatography

The use of 1,3-dichlorotetrafluoroacetone allows the conversion of the iodoamino acids into a chemical form convenient for following chromatographic separation on silica as an adsorbent and benzene or chloroform as a solvent. The time required for derivatization and TLC separation is less than one hour. The outstanding resolution of the substance of interest, as well as the sensitivity of the radiochemical analysis, makes the method convenient for the rapid determination of minute quantities of thyroid hormones.

Gas chromatography of amino acids

This review summarizes all papers that have appeared on the gas chromatography of amino acids (including the iodoamino acids) and their enantiomers in the period 1956-mid-1974. It has been found that the methods used for analysis of amino acids can be divided into three classes: (1) degradative procedures and techniques for converting the amino acid into another chemical compound; (2) procedures based on esterification of the carboxyl group and derivatization of the a-amino and other reactive groups in at least two steps; and (3) procedures based on a simultaneous derivatization of the carboxyl and a-amino groups in one reaction medium. For the treatment of the amino acid or its alkyl ester, three approaches can be distinguished for the two latter cases, i.e., acylation, alkylation (including silylation) and condensation. Of the procedures used for the resolution of optical antipodes, two methods are discussed, namely analysis of diastereoisomers on optically inactive stationary phases and separation of enantiomers on optically active stationary phases.