Biomedical subjects

J Bláha

Publications and source records attributed to J Bláha.

At least 19 recordsLinked to original sources

PubMed2006

[Resting energy expenditure during hemodialysis].

Very few studies have so far reported about resting energy expenditure (REE) in chronic renal failure and there is no information available on REE during hemodialysis (HD). Hypothetically, we can expect an increase in REE during HD procedure (due to the inflammatory response to extracorporeal blood circuit). However, such increase in REE could be modified by thermal balance of the procedure. In our study, REE was measured by indirect calorimetry (Deltatrac Datex) in a group of 13 HD patients (7 males and 6 females, mean age 59.8 +/- 13.5 years). In each patient, REE was assessed during two HD sessions: one isothermic and one thermoneutral. All other HD parameters were kept constant. The control group consisted of 14 healthy subjects (4 males and 10 females, mean age 41.3 +/- 20.5 years) with normal renal function. There was a significant difference in thermal balance between the two HD settings: -199 kJ/HD in isothermic and -4kJ/HD in thermoneutral HD sessions (p < 0.01). Measured REE values obtained in HD patients before HD session (7 316 +/- 919 kJ/day/1.73 m2) did not differ significantly from those of the healthy controls (7 264 +/- 1 016 kJ/day/1.73 m2). Similarly, there was no significant difference in calculated EE values (Harris-Benedict equation). In the 10th minute of the HD session, there was a slight, transitory decrease in REE (mean decrease by 3.2% during isothermic and by 2.8% during thermoneutral HD session, ns). In the 70th minute, REE returned to pre-dialysis values. After a light meal in the 110th minute REE increased by 8% during isothermic and by 6.3% during thermoneutral HD session. At the end of the HD session (i.e. in the 215th minute) REE again returned to pre-dialysis values. Intra-dialysis changes in REE were similar in both isothermic and thermoneutral HD sessions. The results of our study did not confirm the expected influence of HD procedure on REE in the two different thermal HD settings. We conclude that there is no significant difference between REE in HD patients and healthy controls and that REE values are not significantly influenced by hemodialysis procedure.

Calorimetry, Indirect↗

PubMed2006

[Pulmonary endarterectomy--the surgical treatment of chronic thromboembolic pulmonary hypertension].

BACKGROUND: Chronic thromboembolic pulmonary hypertension (CTEPH) in indicated cases can be successfully treated by the endarterectomy of pulmonary arteries (PEA). Symptomatically not treated CTEPH has highly unfavourable prognosis. Five years survival of patients with mean pulmonary pressure over 50 mmHg is only 10%. PEA was not available in the Czech Republic till 2004, when PEA program was initiated it the Cardiocenter of the General teaching hospital in Prague in collaboration with leading clinics in that field (Prof. Mayer, University of Mainz, BRD). METHODS AND RESULTS: Up-to-date surgical technique, which in various modifications has been used at majority of clinics, was elaborated by Jamieson and Daily at University of California in San Diego. It is based on reverse endarterectomy performed during complete circulatory arrest with brain protection by deep hypothermia. Till September 2005 twelve patients were operated with zero mortality. In one patient a suture of atrial septum defect was necessary to perform along. Average time of the circulatory arrest was 45 minutes; duration of the extracorporal circulation was 334 minutes. Average duration of the operation was 450 minutes. Duration of the mechanical ventilation was in average 45.5 hours. After one month already haemodynamic parameters (mPA, CI, PVR) significantly improved or normalized and the average length in the test of six minutes walking increased by 132 meters. CONCLUSION: PEA represents a treatment method for patients with CTEPH and surgically accessible pulmonary artery obstruction. Centralized care of those patients is a rational necessity enabling to get maximum experience with complicated diagnostics and treatment of those patients. Multidisciplinary collaboration is the essential condition for the success of the program.

Adult↗

PubMed2006

[Monitoring of glucose concentration in critical patients, comparing arterial blood glucose concentrations and interstitial glucose concentration measured by microdialysis technique].

INTRODUCTION: Recent studies have shown that normalization of blood glucose in critically ill patients by intensive insulin therapy significantly decreases their mortality and morbidity. The aim of our study was to compare interstitial glucose concentrations in subcutaneous adipose tissue (measured by microdialysis technique) and arterial blood glucose concentrations to test the suitability of subcutaneous adipose tissue for long-term placement of biosensors for glucose measurement in critically ill patients. PATIENTS AND METHODS: 20 patients (16 men and 4 women) after cardiac surgery hospitalized at postoperative intensive care unit were included into the study. Mean age was 68 +/- 10 years, BMI was 28.3 +/- 3.9 year. Only patients with glycemia higher than 6.7 mmol/l at a time of admission to the ICU were included. Samples for measurement of interstitial glucose concentrations were collected in 60 minutes intervals during 48 hours using microdialysis of the subcutaneous adipose tissue. Perfusion fluid was 5% mannitol, perfusion rate was 1 microl/min. Arterial blood glucose concentration was measured in 60 minutes intervals, absolute concentrations of interstitial glucose were calculated using ionic reference technique. RESULTS: Mean arterial glucose concentration during the study was 6.7 +/- 0.56 mmol/l, absolute concentration of glucose in interstitial fluid was 3.55 +/- 0.58 mmol/l. Mean correlation coefficient between arterial and interstitial concentrations was 0.77 +/- 0.15. CONCLUSION: Our study demonstrated good correlation between interstitial glucose concentrations in subcutaneous adipose tissue and arterial blood glucose concentrations in post-cardiac surgery patients. Further studies are needed to evaluate this relationship in patients with more severely disturbed perfusion of subcutaneous adipose tissue.

Aged↗

PubMed2003

Comparison of different techniques of hemodialysis vascular access flow evaluation.

Measurement of vascular access flow (QVA) has been suggested as a method of choice for vascular access quality (VAQ) monitoring. Besides traditional duplex Doppler, a number of bedside methods based mostly on the Krivitski principle of QVA evaluation from recirculation at reversed needles (RX), have been developed. This work compares ultrasonic dilution (UD), taken as a reference, HD01, Transonic Systems; duplex Doppler (DD); thermodilution (TD), BTM, Fresenius; optodilutional RX measurement (ORX), Critline III, R-mode, HemaMetrics; direct optodilutional QVA evaluation from jumpwise changes in ultrafiltration rate at both normal and reversed needles connection (OABF), Critline III, ABF-mode; and direct transcutaneous optodilutional QVA evaluation (TQA), Critline III TQA. Firstly, reproducibility of each method was assessed by duplicate measurement at unchanged conditions. This was followed by paired measurement with each method performed at controlled change in relevant measurement condition (two different extracorporeal blood flows in UD and TD, changed sensor position in TQA). Finally paired measurements by each method and the reference method performed at identical conditions were evaluated to assess accuracy of each method. The simple Krivitski formula QVA=QB(1-RX)/RX was used wherever manual QVA calculation was needed. Very high reproducibility was seen in UD, both for measurement at the same extra corporeal blood flow (QB) (correlation coefficient of duplicate measurement r=0.9702, n=58) and for measurement at two different QB (r=0.9735, n=24), justifying its current status of a reference method in QVA evaluation. Slightly lower reproducibility of TD measurement at the same QB (r=0.9197, n=40) and at two different QB (r=0.8508, n=168) can be easily overcome by duplicate measurement with averaging. High correlation of TD vs. UD (r=0.9543, n=54) makes TD a viable clinical alternative in QVA evaluation. Consistently different QVA obtained at two different QB should prompt closer investigation of anatomical conditions of the access. Use of the simple Krivitski formula in TD (which measures total recirculation, i.e. sum of access recirculation and cardiopulmonary recirculation) brings about underestimation of QVA, which progressively increases from QVA of about 600 mL/min up. Good correlation, although with significant scatter (r=0.8691, n=27) was found between the DD- and UD-based QVA. By far the worst reproducibility at the same QB from among the investigated methods was found in ORX (0.6430, n 23). Also the correlation of ORX vs. UD was lower than in other methods (r=0.702, n=33) and general overestimation of QVA by about 25% was noted. Correlation of OABF vs. UD (r=0.6957, n=26) was slightly better than that of ORX and it gave less overestimated values. The TQA method showed very high reproducibility (r=0.9712, n=85), however only for unchanged sensor position. Correlation of QVA measured at two different sensor positions was much worse (r=0.7255, n=22). Correspondence of TQA vs. UD was satisfactory (r=0.8077, n=36). Skilled and experienced operators are a must with this method.

Catheters, Indwelling↗

PubMed2002

[Mediators of amyloidogenesis and cytokines in dialysis-related amyloidosis].

BACKGROUND: Dialysis related amyloidosis (DRA) is a severe complication of the long-term dialysis treatment. beta 2 microglobulin and probably other factors influence the development of amyloid deposits. We investigated some of these factors during hemodialysis session. METHODS AND RESULTS: We investigated 20 patients undergoing regular hemodialysis treatment. Patients were divided into AMYL group (with histologically proven DRA) and NE-AMYL group (without signs of DRA). Plasma levels of following factors were investigated using standard ELISA kits: serum amyloid A (SAA), interleukin-6 (IL-6), macrophage-colony stimulating factor (M-CSF). In addition plasma concentrations of C-reactive protein (CRP) and beta 2 microglobulin (beta 2M) were investigated in the AMYL group. All these parameters were studied during different time periods of the hemodialysis session. Plasma levels of SAA and IL-6 did not increase during hemodialysis session and we did not find any difference in plasma levels of these factors between the group of patients with AMYLand NE-AMYL. Plasma levels of M-CSF increased during hemodialysis and its levels in AMYL group were significantly higher in comparison with NE-AMYL group at the end of hemodialysis session (5345.10 +/- 340.42 vs. 3458.45 +/- 332.15 pg/ml, p = 0.0011). A linear correlation was found between plasma levels of SAA and CRP during hemodialysis whereas no correlation was found between plasma levels of beta 2M and other factors. CONCLUSIONS: Our study suggests that plasma levels of M-CSF are increased in patients with chronic renal failure. Significant increase of M-CSF levels in the AMYL group could lead to greater activation of monocyte-macrophage system and could serve as factor supporting amyloid deposition process.

Amyloidosis↗

PubMed2002

[Massive pulmonary embolism after delivery by cesarean section].

OBJECTIVE: To give an overview of the preventive and therapeutic measures in thromboembolic disease in association with pregnancy and delivery. SUBJECT: Case report. SETTING: Department of Obstetrics and Gynaecology, First Faculty of Medicine, Charles University and General Faculty Hospital, Prague. SUBJECT AND METHOD: The surgical treatment of massive pulmonary embolism in a patient after delivery by caesarean section. CONCLUSION: Surgical embolectomy still has its place in the treatment of pulmonary embolism in the early phase of critical cases, when thrombolysis is contraindicated, and mechanical disintegration with the catheter is unsuccessful. In such cases it is the only one possibility of saving the patient. However, prevention of thromboembolic disease remains of primary importance.

Adult↗

PubMed2001

Permanent sequelae after burns and tested procedures to influence them.

Although permanent sequelae of deep burns always persist, they can be very favourably influenced if we start soon after the injury. There are several possibilities: very early rehabilitation by positioning and supports prevents the shortening of tendons and ligaments surrounding the large joints and thus reduces post-traumatic oedema. By selecting the correct surgical technique at the right moment, we achieve an optimal course of healing and scar formation. Great attention must be paid to infection and its prevention. After healing it is important to apply compressive aids soon, preferably in combination with silicone and similar materials. For lubrication it is better to use creams with a high water content. Ensure the optimal mental well-being of affected patients. If the patient communicates well, do not hesitate to use psychoanalytic methods to reduce emotional and verbal blocks related to the injury.

Burns↗

PubMed2001

[Evaluation of vascular access for hemodialysis using combined measurement of recirculation in normal and inverted needle placement and determination of blood flow through the access].

The article describes novel method of vascular access quality assessment by means of combined measurement of recirculation with normal and inverse needles placement and calculation of vascular access blood flow from the recirculation data. Blood flow values seen in a large group of patients ranged from as low as 200 ml/min up to as high as 2 l/min. Females and diabetics exhibited lower values as compared to males and non-diabetics. The method enables to detect a number of anomalous sates which cannot be detected by conventional means based on monitoring of pressures or recirculation measurement at normal needles placement only (stenosis between both needles, uintentionally erroneous placement of needles in accesses with a loop). Assessment of access blood flow is suitable also for evaluation of interventions on the access, such as percutaneous transluminal angioplasty or surgical narrowing of anastomosis in case of too high blood flow.

Arteriovenous Shunt, Surgical↗

PubMed2000

Hourly diuresis in patients with extensive burns.

The values of hourly diuresis in 40 patients with extensive burns were investigated and expressed graphically during the stage of burn shock. By analysis of the values and the patient's condition, a marked effect of the mental state on the course of burn shock and further treatment at the intensive care unit of the Prague Burns Centre was found. On a preliminary basis the effects of some drugs on the values of hourly diuresis were investigated.

Burns↗

PubMed1999

Therapeutical aspects of using citalopram in burns.

CONCLUSION OF THE ICU: Preliminary results from this stage of our study demonstrate a significant decrease of the duration of oedema, probably due to the effects of the inhibition of vascular hyperpermeability. This means that patients under Citalopram therapy can undergo surgical procedures such as necrectomies and autografts sooner because they are stabilized as early as the beginning of their treatment. Particularly the patients with burned faces and deep dermal burns have a better prognoses in respect to cosmetics. CONCLUSION OF THE PSYCHOLOGIST: From the beginning of the study to the present time, no patient experienced PTSD. The compared group of out-patients had been treated on average of 3 months when the first signs of a reduction in the clinical symptoms of PTSD was registered. The clinical onset of the therapeutical effect--on average in the third week--is comparable with references from anxiety or inhibitory depression treatment by using Citalopram. We suggest, at present, that the above-mentioned, preliminary results of our study have shown that Citalopram treatment has a beneficial effect on emotional disturbances in severely burned patients. CONCLUSION OF THE SCAR SPECIALIST: Seropram is a very useful preparation in burn praxis. When we apply it as a bolus 40 mg i.v. immediately after admission to the ICU, the scarring process is very good and hypertrophic scars are not seen. When we apply Seropram in the form of a continual infusion, using the injectomat during a 24-hour period, scarring is better than in the control group, but hypertrophic scarring is not out of the question.

Adolescent↗

PubMed1997

Prevention and therapy of postburn scars.

The cosmetic and functional result in postburn scar deformities is influenced by following factors: 1. The type of patient's central nervous system and his response to burn injury. 2. Depth and site of burn areas. 3. Early excision and grafting. 4. Infection complications, their severity and location. 5. Fixation of dressings should be done using elastic materials and applied for so long until stabilisation of scars is completed. Elastic materials should be combined with rigid pressure and pressure massage. 6. Congenital predisposition of the patient to hypertrophic scarring.

Bandages↗

PubMed1996

Use of continuous blood volume monitoring to detect inadequately high dry weight.

A continuous blood volume monitoring (CBVM) device (Inline Diagnostics, Riverdale, USA) was used to study response to prescribed ultrafiltration during haemodialysis (HD) in 66 stabilised HD patients. Fifty percent of patients showed the expected linear decrease in BV right from the beginning of HD (group 1), 32% exhibited no decrease at all (group 2), while eighteen percent formed the transient group 3 which showed a plateau of varying length after which a decrease occurred. The correct setting of dry weight was verified through evaluation of the ratio of extracellular fluid volume to total body water (VEC/TBW) in 26 patients by means of whole body multifrequency impedometry MFI (Xitron Tech., San Diego, USA) and through measurement of the Vena Cava Inferior diameter (VCID) pre and post HD (in 6 and 5 patients from groups 1 and 3 and from group 2, respectively). The mean VEC/TBW in groups 1 and 3 was 0.56 pre and 0.51 post HD as compared to 0.583 and 0.551 in group 2. VCID decreased on average by 14.1% in groups 1 and 3 but remained stable in group 2. Both findings thus confirmed inadequately high estimation of dry weight. Since CBVM is extremely easy to perform it can be used as a method of choice in detecting inadequately high prescribed dry weight. The status of the cardiovascular system must always be considered before final judgement is made.

Blood Volume↗

PubMed1995

[Measurement of water content and distribution using whole-body multifrequency impedance in a healthy population in diseases of the kidney].

BACKGROUND: The whole-body multifrequency impedometry (MFI) is a new noninvasive method suggested for assessment of hydration status and distribution of the total body water into extra- and intracellular compartment. However, due to its as yet limited use reference values are still lacking. The aim of this work was to evaluate total body water (TBW) and its intra- (VIC) and extracellular compartment (VEC) from electrical resistances of intra- and extracellular fluid and to measure cell membrane capacity by means of MFI in healthy population and in renal patients. METHODS AND RESULTS: MFI investigation was performed in 21 healthy individuals (group A), 19 patients followed for renal insufficiency but not yet dialysed (group B) and in 15 haemodialysis patients (group C). The bioimpedance analyzer BIS 4000B (Xitron Technologies, San Diego, USA) was used throughout the study. TBW values established by means of MFI corresponded very closely to those ones calculated from Watson's formulae. The ratio VEC/TBW was found to be related to age with regression analysis parameters being very similar both in group A and groups B, C: group A: VEC/TBW = 0.4696 + 0.0011. Age (r = 0.512) groups B, C: VEC/TBW = 0.4574 + 0.0016. Age (r = 0.420). (For group C the post-dialysis values were used). Close correlation of VEC changes with ultrafiltered volume during haemodialysis session (r = 0.87 pri n = 87) indicates mostly extracellular origin of ultrafiltrate. The highest capacity of the cellular wall was found in healthy individuals, the lowest values were seen in the dialysed group. During dialysis the capacity rose to values seen in the non-dialysed group of renal patients. Interindividual scater over 40% in CIC value is caused by differences in body size. Normalized capacity CIC/VIC in healthy group is 0.104 nF/L +/- 10% on average. In renal patients values from 0.73 to 0.9 nF/L were seen. With regard to low variation of CIC/VIC in health, this parameter can be considered a possible candidate for screening assessment of the renal patients' hydration status. CONCLUSIONS: MFI was found suitable for monitoring of water content and distribution in the body both in out-patient department as well as during haemodialysis.

Adult↗

PubMed1995

Influence of the dialyzer membrane material on sodium transport in hemodialysis.

Traditionally Gibbs-Donnan coefficients based on the mean charge of plasma proteins are used as the only correction factor in equations describing sodium transport across the dialyzer membrane. This ignores the possible impact of the membrane material. Correction coefficients (CC) of the whole dialyzer were measured during in vivo dialysis as a quotient of dialysate to plasma sodium in an equilibrated state for different membrane materials used in commercially available dialyzers. Their mean value and correlation with total plasma protein content (TPP) were evaluated. CC for the six materials evaluated differed both in the intercept and slope of the regression line CC versus TPP: Cuprophan 1: CC = 1.0253 - 0.00017 x TPP; Hemophan 1: CC = 1.119 - 0.00175 x TPP; Hemophan 2: CC = 1.095 - 0.00111 x TPP; PMMA: CC = 1.0353 - 0.00044 x TPP; SCE:CC = 1.114 - 0.00145 x TPP; and Cuprophan 1:CC = 1.0562 - 0.00065 x TPP. The observed differences are attributed to the different charge densities of the membrane materials and suggest that for a precise description of sodium transport, the role of the membrane material needs to be considered.

Blood Proteins↗

PubMed1995

Study on sodium and potassium balance during hemodialysis.

To acquire data for adequate ultrafiltration (UF) control, sodium and potassium balance was investigated during hemodialysis (HD) in 16 hemodialyzed patients. Overall balances were evaluated from concentration measurements of the in- and outflowing dialysate and pre- and postdialysis plasma. The diffusive and convective part of the electrolyte removal and its intra- and extracellular space (ICS, ECS) component were calculated. During a 5-h HD, 40-110 mmol of potassium is removed, predominantly by diffusion (72-88%). Calculation shows that 40-70% of the removed amount is taken from the ICS. Sodium's overall HD showed much higher scatter, ranging from positive values to 500 mmol removal. The diffusive component was positive in most cases. By ultrafiltration sodium is removed in all cases. Calculations also showed in all cases that sodium was delivered to the ICS. This is in contradiction with the general belief that exchangeable sodium is distributed solely in ECS (1,2,6,7). This may be a sign of the effort to keep changes of ICS osmotic load at a minimum. Based on the finding of the exchange of sodium for potassium in the cellular wall, a method has been devised to calculate the UF fraction removed from EC (UFEC) expressed as a coefficient KEC = UFEC/UFToT, with UFToT being the total fluid volume removed during the HD session.

Humans↗

PubMed1995

Analysis of the urea generation rate and the protein catabolic rate in hemodialyzed patients.

The urea generation rate (G) and the protein catabolic rate (PCR) have been investigated in two groups of hemodialyzed patients over a whole week cycle, one with zero residual renal function (Kr = 0) dialyzed thrice weekly and the other dialyzed twice weekly with nonzero residual renal function. The two-pool model of urea kinetics was used. No relationship between patients' age and the PCR was found, and also no difference in the PCR between males and females was seen. All patients with a PCR < 0.8 g/kg/day had a midweek predialysis plasma urea level well below 25 mmol/L, which clearly documents the value of a kinetic approach in early detection of patients at risk for malnutrition. In the thrice weekly dialyzed group, a statistically significant relationship was found between PCR and KT/V:PCR = 0.582 + 0.253 x KT/V, r = 0.374 with p < 0.05. In the twice weekly dialyzed group with nonzero Kr, contribution of the residual renal function had to be included into KT/V to reach a level of statistical significance of PCR = 0.697 + 0.18 x KT/V, r = 0.481 with p < 0.05. With regard to values of Kr encountered in the investigated group (0-3.5 ml/min), its influence upon PCR is higher than a volumetrically equal increase in excretorial efficacy of the artificial kidney. The G in the thrice weekly dialyzed group was found to be dependent on the length of the interdialytic interval over which it was evaluated. Over the intervals Friday-Monday, Monday-Wednesday, and Wednesday-Friday the following mean values of G were obtained: 0.155, 0.180, and 0.188 mmol/min, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Cyclic AMP Receptor Protein↗

PubMed1993

[Prediction of needs in dialysis therapy].

Planning of future needs of Renal Replacement Therapy (RRT) Programme is frequently based on comparison of national data with data from other countries. Often, the dynamics of RRT development is disregarded and dialysis and transplantation assessed as separate entities, too. Such approach may lead to underestimation of present level of RRT availability and overestimation of immediate future needs. Transplantation activity and number of patients requiring dialysis are interrelated variables. Under steady state, their relation may be described as N = TX + U where N denotes incidence of chronic renal failure, TX transplantation activity, and U stands for mortality rate of dialysed population. Considering mortality rate equal to 10% of dialysed population (P), an equation describing the interrelation of transplantation activity and number of patients requiring dialysis may be devised: P = (N - TX)/0.1. This equation can be used to calculate target values of RRT programme. The time course of RRT needs to reach the target figures may be predicted from a simple differential equation dP/dT = N - 0.1. P - TX, taking into account dynamic character of this process.

Czech Republic↗

PubMed1993

[Nephrologic aspects of HIV infection].

The authors present a review of nephrological complications of HIV infection. The latter can be divided into electrolyte disorders and disorders of the water balance, acute renal failure, non-specific affections of the glomeruli, tubules and renal vessels and so-called HIV nephropathy. While the three former groups of complications are non-specific, coincidental, HIV nephropathy is obviously a specific complication of HIV infection. It is characterized by the nephrotic syndrome with rapid progression to irreversible renal failure. As to the histological appearance, it is focal segmental glomerulosclerosis. Survival of asymptomatic HIV infected patients in a dialyzation programme does not differ from other patients. The prognosis in case of developed AIDS is, however, unfavourable. Transplantation of HIV positive donors and recipients is not recommended. The authors present also basic data on the possible nephrotoxicity of the most frequently used preparations in the treatment of HIV infected subjects.

AIDS-Associated Nephropathy↗