Surgical conditions with rocuronium versus suxamethonium in cesarean section: a randomized trial

BACKGROUND

Onset times and conditions for intubation after rocuronium versus suxamethonium at cesarean section have been evaluated, but no study thus far has examined the influence of these neuromuscular blocking drugs on the surgical conditions or their effect on the duration of surgery and the ease of fetal delivery. We aimed to compare the surgical conditions for delivery in parturients who received deep neuromuscular block with rocuronium with those who had induction with suxamethonium.

METHODS

Ninety patients undergoing cesarean section under general anesthesia were randomized to receive either rocuronium 0.6 mg/kg or suxamethonium 1 mg/kg for tracheal intubation and delivery. Times to delivery and the quality of surgical conditions, using a five-point Surgical Rating Scale for Delivery (SRSD) ranging from 1 (poor) to 5 (excellent), were evaluated.

RESULTS

The median SRSD (range) was found to be significantly better in the rocuronium group [4 (3-5) points vs 3 (2-4) points with suxamethonium (P <0.001)]. Whereas the mean (SD) induction-to-intubation interval was longer with rocuronium [106 (34) s vs 68 (32) s with suxamethonium (95% CI of the difference 24 to 52 s, P <0.001)], the incision-to-delivery interval was shorter in the rocuronium group [147 (68) s vs 196 (51) s with suxamethonium (95% CI of the difference -75 to -24 s, P <0.001)]. The mean induction-to-delivery intervals were similar [268 (73) s vs 276 (63) s, respectively].

CONCLUSIONS

Whereas the induction-to-delivery intervals were comparable, we found rocuronium superior to suxamethonium in allowing better surgical conditions for fetal delivery, which enabled an easier delivery and a shorter incision-to-delivery interval.

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.

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.

[Analgesia for labour in the Czech Republic in the year 2011 from the perspective of OBAAMA-CZ study - prospective national survey]

GOAL OF THE STUDY

The aim of national survey was to describe current practice for analgesia during labour provided by anaesthesiologists in the Czech Republic (CZE).

TYPE OF THE STUDY

National prospective observational.

SETTING

49 obstetric departments in CZE.

METHODS

We aimed to enrol all 97 obstetric departments in CZE and to monitor every case of anaesthetic care in peripartum period during November 2011. Data were recorded to Case Report Form with two parts (Demography 2010 and Case Report) into TrialDB database (Yale University, USA; adapted IBA, MU, CZE). Demographic data for CZE were obtained on request by ÚZIS. The data were analysed using SPSS 22.

RESULTS

We enrolled 1943 cases of anaesthesiological care and 579 (29.8%) of them was to relief labour pain. Population and center weighted estimate of incidence of epidural labour analgesia was 12.5% (95% CI: 10.6% - 14.4%). Epidural analgesia was the most frequently applied via Tuohy needle G18 (97.8%), with administration of an epidural catheter G20 (95.7%), via medial approach (98.8%), in lateral position (76.7%) by the loss of resistance method (94.3%). All administrations of epidural analgesia were started by initial bolus, only in 28.2% of cases were followed continously. Always has been applied mixture of local anaesthetic with sufentanil at a dose of 3-10 mcg. Bupivacaine was most frequently used local anaesthetic (80.7%), followed by levobupivacaine (12.6%). Median concentrations both bupivacaine and levobupivacaine were 0.125% (min. 0.1%, max. 0.3%).The most common complication of epidural analgesia was repeated puncture (21.2%), blood in the catheter (1.4%), blood in the needle (1.2%), unintended puncture of the dura mater (0.7%) and transient paresthesias (0.5%).

CONCLUSION

In comparison to previously published data there was trend for lower incidence of epidural analgesia for labour in the CZE.

Analysis of a retrospective double-centre data-collection for the treatment of burns using biological cover Xe-derma®

Xe-Derma(®) is a new biological acellular temporary wound cover derived from pig dermis in the form of a mesh of collagen and elastic fibers. It is recommended for use in similar indications as classical pig xenografts. A data collection of 2 burns centres in the treatment of burns with Xe-Derma(®) was obtained from the medical records of 101 patients admitted from January 1, 2010 to December 31, 2011. The primary objectives of the study were to assess efficacy and safety when using Xe-Derma(®) in burn treatment, and to analyse the course of healing. The secondary objectives were to define the suitable spectrum of indications of Xe-Derma(®) in terms of burn depth, and to evaluate subsequent scarring using the Vancouver Scar Scale. No undesirable systemic effects or adverse device events were observed. The use of Xe-Derma(®) was not associated with a higher risk of burn wound infection. On the other hand, the infection was the most common cause of Xe-Derma(®) dissolution. The majority of patients (81.4%) had no signs of Xe-Derma(®) dissolution. The mean healing time in the group of patiens under review was close to 12 days and mean hospitalization time was almost 14 days. Using Xe-Derma(®) proved to be effective as a temporary covering for partial-thickness burns with the capacity of spontaneous healing. It proved to be a well-tolerated wound coverage with minimal complications and low level of pain during dressing changes. Xe-Derma(®) firmly adhered to the wound bed. There was a lower frequency of wound dressing changes and only a minimal rate of wound infection.

[Peripartal life-threatening hemorrhage - interdisciplinary consensus opinion]

22 experts from the fields of gynecology and obstetrics, anesthesiology and resuscitation, intensive care, hematology and transfusion medicine has developed recommendations for diagnosis and procedure for life-threatening peripartum haemorrhage, which is still one of the most common causes of maternal mortality in childbirth. This guidelines, which is valid for the Czech Republic, supported by a total of 10 professional medical societies. There are based on new knowledge applicable at this time and is focused mainly on eliminating the most common causes of bleeding during delivery and prevention of haemorrhagic shock.

[Childbirth analgesia and anesthesia in the Czech Republic in 2012. The 20th anniversary of post-graduate education]

The aim of this study was to ascertain the current status of analgesia and anesthesia used during childbirth in the Czech Republic. Using data from questionnaires, an overview of individual labor-related anesthetic procedures and methods and frequency of their use was obtained. A positive trend in the increase of neuroaxial methods used in maternity wards over the last twenty years has been the result of a systematic program of interdisciplinary post-gradual education for doctors and birth attendants in the Czech Republic.

Hepcidin expression in adipose tissue increases during cardiac surgery

Hepcidin, a key regulator of iron metabolism, plays a crucial role in the pathogenesis of anemia of chronic disease. Although it is produced mainly in the liver, its recently described expression in adipose tissue has been shown to be enhanced in massive obesity due to chronic low-grade inflammation. Our objective was to study the changes in hepcidin expression in adipose tissue during acute-phase reaction. We measured hepcidin mRNA expression from isolated subcutaneous and epicardial adipose tissue at the beginning and at the end of the surgery. The expression of mRNAs for hepcidin and other iron-related genes (transferrin receptor 1, divalent metal transporter 1, ferritin, ferroportin) were measured by real-time RT-PCR. Hepcidin expression significantly increased at the end of the surgery in subcutaneous but not in epicardial adipose tissue. Apart from the increased levels of cytokines, the parameters of iron metabolism showed typical inflammation-induced changes. We suggest that acute inflammatory changes could affect the regulation of hepcidin expression in subcutaneous adipose tissue and thus possibly contribute to inflammation-induced systemic changes of iron metabolism.

Thrombophilia and pulmonary endarterectomy

In the present study, we compared groups of patients with and without thrombophilia, who underwent pulmonary endarterectomy (PEA), definitive treatment for chronic pulmonary hypertension resulting from thromboembolic disease.

METHODS AND PATIENTS

Between September 2004 and June 2007, we operated 54 patients with CTEPH. We divided our patients into three groups. Group I patients, had one or more signs of serious thrombophilia (15 patients), Group II patients, had no signs of thrombophilia (23 patients without thrombophilia and without Methylenetetrahydrofolate Reductase (MTHFR)), and Group III patients with MTHFR (16 patients with MTHFR only, without any serious thrombophilia).

RESULTS

After the surgery, there was a statistically considerable improvement of hemodynamic parameters (mPA, CI, PVR) in all groups, without a statistical difference between the groups. Comparison of all these groups showed more complications in-group I (thrombophilia), in particular reperfusion oedema, pericardial effusion, and renal insufficiency. Within one month, there was a considerable improvement or normalisation of haemodynamic parameters, an increase in walking distance at the six-minute walking test, and NYHA classification with no significant difference between the three groups.

CONCLUSIONS

Early hemodynamic results of patients with thrombophilia after PEA, were comparable to the results of patients without thrombophilia, when we looked at both clinical and hemodynamic improvements. We did not find any differences when we looked at the results between Group II and Group III (MTHF), when we considered the number and type of complications. Patients with thrombophilia in Group I had statistically higher morbidity, especially when it came to a higher number of reperfusion oedema, pericardial effusion, and renal insufficiency.

[The treatment of hyperglycaemia in critically ill patients: comparison of standard protocol and computer algorithm]

INTRODUCTION

Hyperglycemia is commonly observed in patients hospitalized on intensive care units. It is has been demonstrated that normalization of blood glucose level using intensive insulin therapy significantly improves prognosis of these patients. The aim of our study was comparison of standard protocol of intensive insulin therapy used on cardiac surgery ICU in General University Hospital in Prague and computer algorithm MPC (Model Predictive Control).

PATIENTS AND METHODS

20 patients with glycaemia higher than 6.7 mmol/l at the time of admission to ICU were included into the study, 10 subjects were randomized for standard treatment, 10 for treatment with MPC algorithm. Glycaemia was measured hourly during 48 hours, insulin infusion was rate was adjusted hourly in MPC algorithm or in 1-2 hours in standard protocol group.

RESULTS

Blood glucose levels were in the target range significantly longer in MPC relative to standard protocol group (26.3 +/- 2.1 hrs vs 20.3 +/- 2.5 hrs). Mean blood glucose was also lower using MPC algorithm (6.47 +/- 0.11 vs 6.72 +/- 0.23 mmol/l). On the contrary the target range was established faster using standard protocol (8.9 +/- 1.2 vs 10.3 +/- 0.9 hrs), duration of hyperglycaemia was the same in both groups (7.3 +/- 1.9 in standard protocol vs 7.3 +/- 1.3 hrs in MPC algorithm). Average 48-hours insulin dose was higher in MPC than standard protocol group (230.2 +/- 38.8 vs 199.1 +/- 27.8 IU/48 hrs). 2 hypoglycaemic episodes occured in 2 patients in standard protocol group.

CONCLUSIONS

Our results show that the use of MPC algorithm result in more effective blood glucose control in critically ill patients than standard protocol.

Increased angiotensinogen production in epicardial adipose tissue during cardiac surgery: possible role in a postoperative insulin resistance

Critical illness induces among other events production of proinflammatory cytokines that in turn interfere with insulin signaling cascade and induce insulin resistance on a postreceptor level. Recently, local renin-angiotensin system of adipose tissue has been suggested as a possible contributor to the development of insulin resistance in patients with obesity. The aim of our study was to determine local changes of the renin-angiotensin system of subcutaneous and epicardial adipose tissue during a major cardiac surgery, which may serve as a model of an acute stress potentially affecting endocrine function of adipose tissue. Ten patients undergoing elective cardiac surgery were included into the study. Blood samples and samples of subcutaneous and epicardial adipose tissue were collected at the beginning and at the end of the surgery. Blood glucose, serum insulin and adiponectin levels were measured and mRNA for angiotensinogen, angiotensin-converting enzyme and angiotensin II type 1 receptor were determined in adipose tissue samples using RT PCR. Cardiac surgery significantly increased both insulin and blood glucose levels suggesting the development of insulin resistance, while serum adiponectin levels did not change. Expression of angiotensinogen mRNA significantly increased in epicardial adipose tissue at the end of surgery relative to baseline but remained unchanged in subcutaneous adipose tissue. Fat expression of angiotensin-converting enzyme and type 1 receptor for angiotensin II were not affected by surgery. Our study suggests that increased angiotensinogen production in epicardial adipose tissue may contribute to the development of postoperative insulin resistance.

[Pilot study to evaluate blood glucose control by a model predictive control algorithm with variable sampling rate vs. routine glucose management protocol in peri- and postoperative period in cardiac surgery patients]

BACKGROUND

Increased blood glucose levels are frequently observed in critically ill patients. Recent studies have shown that the normalization of glycemia by intensive insulin therapy decreases mortality, length of the hospitalization and number of complications.

METHODS AND RESULTS

The aim of this pilot study was to compare blood glucose control by an automated model predictive control algorithm with variable sampling rate (eMPC) with routine glucose management protocol (RP) in peri- and postoperative period in cardiac surgery patients. 20 patients were included into this study (14 men and 6 women, mean age 68 +/- 10 let, BMI 28.3 +/- 5.0 kg/m2). 10 patients were randomized for treatment using eMPC algorithm and 10 patients for routine protocol. All patients underwent elective cardiac surgery and were treated with continuous insulin infusion to maintain glycemia in target range 4.4-6.1 mmol/l. The study duration was 24 hours. Mean blood glucose was significantly lower in eMPC vs. RP group (5.80 +/- 0.45 vs. 7.23 +/- 0.84 mmol/l, p < 0.05). Percentage of time in target range was significantly higher in eMPC vs. RP group (67.6 +/- 8.7% vs. 27.6 +/- 15.8%, p < 0.05). Percentage of time above the target range was higher in RP vs. eMPC group. Average insulin infusion rate was higher in eMPC vs. RP group (4.18 +/- 1.19 vs. 3.24 +/- 1.43 IU/hour, p < 0.05). Average sampling interval was significantly shorter in eMPC vs. RP group (1.51 +/- 0.24 vs. 2.03 +/- 0.16 hour, p < 0.05). No severe hypoglycaemia in either group occurred during the study.

CONCLUSIONS

The results of our pilot study suggest that eMPC algorithm is more effective in maintaining euglycemia in peri- and post-operative period in patients after cardiac surgery and comparably safe as compared to RP.

[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.

Physiology and pathology of skin after burns and derangement of gene expression

Temperature and time are two basic factors influencing the effect of heat on the human organism. The degree of resulting damage also depends on the anatomical organization of the skin and hypodermis. Sweat glands and the vascular supply, with blood flowing in corium and hypodermis, act as an effective thermo-regulators for the deeper structures. Under each fully developed necrosis there is a problematic transient area, also known as a zone of blood stasis, which corresponds to the partial damage caused by heat conducted into deeper structures. In this area during the first 3 days cells are selected according to the resistance to the thermal trauma. The basis genetic information of cells is very resistant, but disorders develop on the genetic expression level. Cells--mainly fibroblasts--which survive the first selection are damaged by the thermal injury to varying degrees and often cause other complications. During synthesis of transcripts of RNA from DNA chains an excessive amount of transcripts can develop, subjecting the receptor to information about the loss of skin firmness in defective feedback to the CNS, blocked by fixed trauma emotion. The status is accompanied by swelling, lymphatic stasis, capillary stasis, changes of the local pH and others. During repair facilitated by inflammatory process, excessive amount of collagen is created, as has repeatedly been proved in experiments. The problem can be partially solved by early compression, which limits the amount of impulses about insufficient firmness of the skin, and improves the circulation, while reducing edema, normalizes pH and optimizes production of transcripts. RNA polymerase lacks the ability to correct perfectly and in fact frequently makes mistakes, even under completely normal physiological conditions. If the pH is wrong, it can make even more mistakes and produce pathological collagen in excessive amounts. RNA is not intended to preserve information permanently, and after a certain time it degrades. The onset of this degradation is determined by the cell as well as the amount of created proteins. If RNA is not degraded on time, overproduction of protein and collagen is a natural consequence of the developed defect. Messenger RNA (mRNA) directs the creation of proteins. In case that it is not properly cut in the cellular nucleus, qualitative and quantitative errors in transcription into the protein develop. The non-information RNA takes an enzyme part and plays a role during the transfer of RNA into the protein. It does not have the correction ability. Transfer tRNA chooses appropriately amino acids and places them into the growing protein chain. At the same time, it can make errors and interchange amino acids.

[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.

[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.

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.

[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.

[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.

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.

[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.

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.

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.

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.

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.

[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.

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.

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)

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.

[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.

[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.

[The effect of erythropoietin therapy on biocompatibility in hemodialysis]

In order to evaluate the treatment with erythropoietin (EPO) on selected indicators of biocompatibility the authors examined 8 patients dialyzed for prolonged periods before treatment (HTK = 0.23, median), during EPO treatment (Recormon, administered by the s.c. route, HTK = 0.28) in the course of 4-hour haemodialysis on dialyzers with a Cuprophan membrane. The examination before and during treatment was made under equal conditions. Heparinization was also equal despite the fact that during EPO in four patients the residual blood volume in the dialyzer was increased. Comparison of the results before treatment and during EPO treatment did not reveal at any of the collection times (before dialysis, during the 15th, 10th, 60th and 235th minute of the procedure significant differences in the number of leucocytes, plasma concentrations of the C5a complement component, number of thrombocytes and activated coagulation times. Plasma concentrations of the thrombin-antithrombin III complex were in EPO during the 60th minute of haemodialysis significantly lower (p < 0.05) than before EPO. The authors conclude that EPO treatment does not have a significant effect on changes in the number of leucocytes in blood during haemodialysis nor on the activation of complement by an alternative way. EPO does not lead to a greater activation of the coagulation system during haemodialysis; the lower concentration of the thrombin-antithrombin III complex suggests the opposite. Explanation of this finding, similarly as detection of the cause of the increased residual blood volume in some patients, calls for further investigation.

[Clinical study of biocompatibility of dialysis membranes made from non-modified and modified cellulose]

Basic biocompatibility parameters of dialysis membranes made of non-substituted regenerated cellulose (NRC) and cellulose membranes with hydroxyl groups substituted, to a higher (H) or lower (L) degree, by dl-ethyl-amino-ethyl groups (DEAE), or by acetate (CA) were investigated in a 16-week clinical study, involving 10 long-term haemodialysis patients. In the 15th minute of dialysis, the decrease in blood leukocyte count, while using NRC (0.24 +/- 0.03 of baseline value, arithmetic mean +/- SEM) was deeper compared with that seen in DEAE-L (0.88 +/- 0.10, p < 0.001), in DEAE-H (0.79 +/- 0.10, p < 0.01), and in CA (0.73 +/- 0.05. p < 0.05). In the 15th minute of the procedure, C5a concentrations, reflecting complement activation, were higher in NRC (4.4 +/- 0.51 micrograms/L) than in DEAE-L (1.41 +/- 0.22, p < 0.001), in DEAE-H (1.68 +/- 0.47, p < 0.01), and in CA (1.68 +/- 0.22, p < 0.01). Activated clotting times were, in the 10th minute of the procedure, significantly longer in NRC (2.94 +/- 0.37 of baseline value) than in DEAE-H (1.74 +/- 0.10, p < 0.05) and, by the end of dialysis, the difference between these membranes (NRC: 1.47 +/- 0.21, DEAE-H: 0.85 +/- 0.08, p = 0.07) was close to the level of statistical significance. The authors conclude: 1. Substitution of the hydroxyl groups of regenerated cellulose reduces the decrease in leukocyte count and complement activation in the initial phase of haemodialysis. 2. At the same time, substitution by DEAE groups may raise thrombogenicity, as indicated by the shorter activated clotting times.(ABSTRACT TRUNCATED AT 250 WORDS)

[14 years of the peritoneal dialysis program at the internal medicine department in Strahov (1978-1991)]

The authors present an account of 14 years experience of the department as regards treatment of chronic renal failure by peritoneal dialysis. Initial experience revealed that this method is feasible as an alternative of haemodialyzation treatment even in case of limited technical possibilities (using the so-called bottle system) but treatment was associated with a high incidence of peritonitis. During the subsequent period the incidence of peritonitis was substantially reduced in conjunction with the elaboration of hygienic provisions, enlightment of patients and a change from the regime of continual exchanges in a home environment to a regime of intermittent peritoneal dialysis performed mostly in hospital. Experience assembled in the department was also important. The longest period of treatment is 60 months. In another 18 patients it is more than 20 months. The most frequent cause of termination is loss of the ultrafiltration capacity of the peritoneum. Several patients had successful transplantations. The prolonged experience can be used at present when the so-called bag system is introduced.

[Results of studies of indicators of hemostasis in hemodialyzed patients during administration of 1-deamino-8-D-arginine vasopressin]

The fibrinolytic activity (FA) evaluated according to the euglobulin clot lysis time was in haemodialyzed patients (3.0 +/- 0.2 arb. u.) lower than in patients with chronic renal failure treated by conservative methods (4.7 +/- 0.6, p less than 0.05) and than in healthy subjects (4.2 +/- 0.4, p less than 0.05). After stimulation by intravenous administration of 1-deamino-8-D-arginine vasopressin the FA in haemodialyzed patients rose to (4.5 +/- 1.6), less than in conservatively treated (14.1 +/- 2.1, p = 0.06) and than in healthy subjects (18.2 +/- 3.9, p less than 0.001). By using specific methods it was proved that the inadequate rise of FA in haemodialyzed patients after stimulation is conditioned by a defect of the release of the plasminogen tissue activator from the vascular wall. Contrary to healthy subjects (7.0 +/- 1.3 vs. 16.7 +/- 2.3 ng/ml, p less than 0.01) is plasma concentration in haemodialyzed subjects (5.3 +/- 0.5 vs. 7.9 +/- 0.8, NS) did not increase significantly. Repeated examinations of some of the haemodialyzed patients revealed that almost 20 months of regular haemodialysis do not lead to further changes of basal (2.9 +/- 0.3 vs. 2.8 +/- 0.2) nor stimulated (4.2 +/- 0.5 vs. 4.8 +/- 0.9) FA. Basal plasma concentrations of the von Willebrand factor were in the dialyzed patients (89.1 +/- 8.8%) higher than in healthy subjects (67.2 +/- 4.4, p less than 0.05). After stimulation the concentration of the von Willebrand factor increased significantly in healthy subjects (99.1 +/- 4.3, p less than 0.01), but not in dialyzed patients (82.9 +/- 3.1, NS), obviously due to the pathological reactivity of their vascular wall. The above findings may be associated with thromboses and atherosclerosis in patients on long-term dialysis.

An equation for calculating postdialysis plasma sodium

Well defined dry weight is a must for adequate UF control during haemodialysis (HD). However, interdialytic weight gain (delta BW) must not be excessive. delta BW is closely related to interdialytic thirst which in turn is strongly influenced by post-dialysis plasma sodium (CPNa post), but little is known about the desired CPNa post. The points below serve as a basis for establishing this value. a) Thirst is mediated by osmoreceptors. b) A strong correlation has been found between delta BW and intradialytic increase in plasma sodium but no such correlation exists with the interdialytic increase in plasma urea. This indicates that fluid intake between dialyses depends solely on electrolytes. c) Pre-dialysis plasma sodium in an individual is stable, indicating that the patient is at his "set value" of electrolyte osmolality. d) Half of the potassium removed during HD comes from the extra- and half from the intracellular space. Assuming that it is desirable not to disturb a patient's pre-dialysis osmotic steady state, it can be calculated that the desired CPNa post should be higher than the pre-dialysis value by half of the intradialytic plasma potassium drop, i.e., approx. CPNa post = CPNa pre + 1 to 2 mmol/l.

Bile composition in patients with chronic renal insufficiency

Very little is known about bile composition in the end stage of chronic renal sufficiency. Patients with this condition are either assigned to a dialysis-transplantation programme, or are treated temporarily with a low-protein diet. Our study was designed to determine bile composition both in a group of ten patients treated with a low-protein diet over a long period of time, and in 11 patients on regular haemodialysis. The patients on haemodialysis were found to have increased bile cholesterol and an increased saturation index in the bile, i.e. changes implying increased risk of cholecystolithiasis. These changes were further enhanced by the effect of a low-protein diet with subsequent increases in cholesterol values and the bile saturation index, as well as a decrease in primary and an increase in secondary bile acids in the bile, i.e. a change in the spectrum of bile acid characteristic for cholecystolithiasis.

[Kidney transplantation in diabetics]

Diabetic nephropathy affects half the type I diabetics and is their most frequent cause of death. While in some countries diabetics account for 25-30% of all newly admitted patients in dialyzation-transplantation programmes, in the CSSR the number of diabetic patients treated by dialyzation or transplantation is small. From August 1985 to June 1988 in the Institute of Clinical and Experimental Medicine a total of 15 isolated transplantations of the kidneys were made in 13 diabetics with serious late complications of diabetes. At present all recipients survive (1-35 months) and only two are treated by an artificial kidney. Progressing vascular complications were in two instances the cause of gangrene of the lower extremity, one recipient had a central cerebrovascular attack. Despite this, successful transplantation caused a marked improvement of the general condition and quality of life. The compensation of diabetes was also, due to intensified insulin therapy, satisfactory in the majority of recipients. Hitherto assembled experience indicates that when the patient is prepared in time, which includes diabetological, nephrological and opthalmological treatment, the results of transplantation treatment in diabetic patients can be comparable with results in should be developed in all transplantation centres in the CSSR and uraemic diabetics should be eliminated from the dialyzation transplantation programme only in case of fundamental contraindications.

Is heparin responsible for enhanced platelet aggregation after haemodialysis?

The platelet aggregation--enhancing action of heparin with adenosine diphosphate and epinephrine was tested in vitro in a group of volunteers. This action of heparin can be eliminated by protamine sulphate which has no effect on platelet aggregation. In dialyzed patients the aggregation effect of heparin manifested itself after haemodialysis and could also be abolished by protamine sulphate. We therefore assumed that the heparin used during dialysis was one of the factors accounting for the increased platelet aggregation after dialysis.