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G Uchman

Publications and source records attributed to G Uchman.

11 recordsLinked to original sources
PubMed1992

[Changes in CSF resorption resistance. Experimental studies].

Lumbar infusion tests (IT) with different infusion rates (0.06 ml/min-1.2 ml/min) were used in order to investigate the intracranial pressure (ICP) and CSF outflow resistance (R) changes. Two groups of animals were studied: control group and animals with an 0.8 ml epidural balloon. In control group (without balloon) significant differences in ICP and R values between the increasing and decreasing IT curve were found. The most pronounced changes were noticed right after the highest infusion rate (40% for ICP value and 49% for R value). The results in the balloon group were very similar and the only difference were delayed ICP and R changes. The results obtained suggest that the determined R values are specific for the applied infusion rate and this phenomenon has to be taken into account in all human studies.

Animals↗
PubMed1990

Early pathomorphological changes and intracranial volume-pressure: relations following the experimental sagittal sinus occlusion.

Saggital sinus occlusion was produced in cats. The intracranial volume-pressure relations were studied using the lumbar infusion tests. Right after occlusion ICP rised from 7.1 +/- 1.8 to 12.4 +/- 4.1 mmHg. The values of outflow resistance and volume-pressure response increased also and remained significantly unchanged with only slight decrease of the volume-pressure response. The morphometric study of the surface veins showed the dilatation of the veins draining to the occluded saggital sinus for about 10-20%. No signs of the blood-brain barrier disruption were observed.

Animals↗
PubMed1990

Net ultrafiltration volume (nUFV) during IPD with acetate or lactate dialysis solutions.

There is debate as to how much acetate in PD solutions influences the nUFV, so we decided to evaluate it during uncomplicated IPD and aseptic peritonitis connected with IPD treatment. In 8 patients dialysed with acetate (35 mmol/L) solutions for 9 +/- 8 months the nUFV (drainage volume minus instillation volume, mL/exchange) was calculated for 1.5 and 4.25% glucose exchanges during uncomplicated IPD and aseptic peritonitis. Then, lactate (35 mmol/L) buffered solutions were used instead of acetate ones and the nUFV was estimated under the same conditions. During uncomplicated IPD as well as peritonitis the nUFV was significantly higher in exchanges with lactate then with acetate solutions when the glucose concentration were comparable. In aseptic peritonitis the nUFV was less decreased with lactate than acetate solutions. We conclude during uncomplicated IPD or aseptic peritonitis in patients dialysed with acetate buffer the nUFV can be improved when acetate in PD solutions is substituted by lactate.

Acetates↗
PubMedDate not supplied

A method to assess the passage of diethyl ether and halothane across the placenta during anaesthesia for caesarean section.

A method was elaborated to assess the transplacental passage of inhalatory anaesthetic agents--diethyl ether and halothane during Caesarean section. The method is based on measurements of blood concentrations of these agents in material venous blood and in arterial and venous blood taken from the umbilical cord during the operation. Halothane and diethyl ether concentrations were determined by means of gas chromatography. The studies were carried out on 2 groups of 25 cases each. The obtained results indicate that diethyl ether passes in a higher degree across the placenta than halothane. The mean ratio of halothane concentrations in foetal venous blood to maternal venous blood determined in 25 cases was 0.664 and diethyl ether ratio was 0.988.

Amniotic Fluid↗
PubMedDate not supplied

[Occlusion of the superior sagittal sinus caused by meningioma, intracranial volume-pressure relations and brain edema].

Fifty-one cases of parasagittal meningiomas were analysed. In 37 cases the tumour was situated in the middle and posterior part of the falx. In 17 cases occlusion of the superior sagittal sinus was diagnosed and confirmed by angiography. No correlation was found between the extent of brain oedema and sinus occlusion and tumour size. However, extensive oedema was present in tumours of high malignancy. Occlusion of the sagittal sinus caused no increase of intracranial pressure or venous stasis. This suggests that sinus occlusion caused by meningioma is completely compensated and has no effect on the preoperative and postoperative course.

Adult↗
PubMedDate not supplied

[Three-phase infusion test].

A new CSF circulation diagnostic procedure is presented. The method is called three-phase infusion test. In phase I the CSF absorption mechanisms were tested within ICP range below 20 mmHg and then the infusion rate of 0.06 ml/min was applied. In phase II the high infusion rate (0.3 ml/min) was used and high ICP increase occurred. This part of the study provided data concerning the ability of alternative CSF outflow routes. In phase III again low infusion rate (0.06 ml/min) was applied. The obtained CSF outflow data in phase III were significantly lower than in phase I. This is the so called persistent outflow facilitation phenomenon. The method described, covering different mechanisms of CSF absorption, enables the complex evaluation of CSF outflow sufficiency.

Animals↗