Biomedical subjects

Z Penková

Publications and source records attributed to Z Penková.

6 recordsLinked to original sources

PubMed1993

[Liquid ventilation. 2].

The authors made two series of experiments in rabbits, using liquid ventilation. The first group was ventilated manually using RM 101 solution with an equilibration period of 30 and 60 sec., Tv = 10 ml/kg after previous administration of 30 ml/kg RM 101 at the beginning. The second group was ventilated using a specially developed liquid ventilator--part of the animals was ventilated with an equilibration interval of 30-90 sec., Tv = 10 ml/kg with administration of an initial dose od 30 ml/kg of RM 101 solution, a part of the animals in a continual manner, i.e. without an equilibration period and without administration of the initial dose of the solution. From the results it is apparent that the optimal way as regards blood gases and minimal manner of liquid ventilation. When this method was used during the 180 minutes of liquid ventilation paO2, paCO2 and pH were within the normal range. The other methods of liquid ventilation led rapidly to hypercapnia and a drop of pH as well as to serious changes in the circulation (hypertension, bradyarrhythmia).

Animals↗

PubMed1993

[Extracorporeal membrane oxygenation. Initial experience at an ECMO center. 1].

The authors describe their initial experience, organization, and problems associated with the development of an EMCO centre. Its main activities are those of a neonatal ECMO centre (to a smaller extent paediatric ECMO and ECCO2R-LF PPV of adults) during the first 4 months of its existence. During the period the ECMO centre was contacted in 10 instances. The referring department indicated the ECMO centre correctly in six instances. However, at least in two instances too late and the patients died (during priming of the ECMO circuit or transport could not be implemented because of the critical condition). In two instances, however, the ECMO staff failed as it was unable to ensure a minimum of seven days of safe operation of ECMO and therefore ECMO was not provided. Based on this experience the authors present an organizational model of the ECMO unit which is formed ad hoc when needed and comprises specialists of various professions from the sphere of emergency medicine. The main purpose of the present paper is to inform referring departments on the indications, selection criteria, contraindications of ECMO in neonates and children and to ensure thus not only smooth communication between the ECMO centre and the referring department but in the first place early referral to the ECMO centre at a time when transport is not yet a problem.

Adult↗

PubMed1993

[Liquid ventilation--1].

The authors investigated in detail the sorption and desorption of oxygen and carbon dioxide in a solution of perfluorocarbons (solution RM 101, Miteni, Italy). From the results of the investigation ensues that maximal oxygen saturation of 77.3 vol.% can be achieved at 8 degrees C. With rising temperature the oxygen concentration in the solution declines (67.6 vol.% at 37 degrees). The saturation of the RM 101 solution corresponds to a linear equation of seventh order (fig. 2). Desorption of the RM 101 solution fully saturated with carbon dioxide, is on the other hand, most rapid at 37 degrees C (after the 13th minute the RM 101 solution contains less than 2% carbon dioxide as compared with 25 vol.% at 8 degrees C during the same period. In general the kinetics of desorption of carbon dioxide in solution correspond to a linear equation of fifth order (fig. 4). From the practical aspect it is not expedient to saturate the RM 101 solution with oxygen longer than 15-20 minutes. The mentioned kinetic parameters are important for the construction of a special liquid membrane or bubble oxygenator. In particular the latter is useful as with its use the authors achieved a 1.9 x higher oxygen concentration in the RM 101 solution than declared by the manufacturer.

Carbon Dioxide↗

PubMed1992

[High frequency "bubble" oscillation ventilation in the neonatal period].

The authors tested their own high frequency, oscillation, "bubble" ventilator on a model of neonatal lungs in vitro and in vivo. They used the effect of oscillations which develop when through fluid (in vivo water) a mixture of air is bubbled and which can be, if the expiration tube is sufficiently rigid, transmitted back into the lungs. If the CPAP circuit is suitably arranged, it can ensure an adequate exchange of blood gases. The authors found marked changes in the amplitude of pressure oscillations as well as of the frequency in relation to the shape of the ending beneath the fluid surface (greatest when a funnel with a 30 mm diameter and 90 degree angle in relation to a normal line projected on the water surface is used). They found that the compliance (C) has no substantial effect on the amplitude nor on the frequency of oscillations. The mentioned bubble system approached as to its efficiency the commercial oscillation ventilator Stephen 3000 SFH and was used in the therapy of respiratory failure in three neonates with body weights of 1250-2700 g. The authors conclude that high frequency oscillation "bubble" ventilation is a cheap, safe and highly effective therapy which can be used in any department providing care of neonates even during transport.

High-Frequency Ventilation↗

PubMed1992

[Pneumoperitoneum in a premature, non-ventilated neonate with respiratory distress syndrome leading to respiratory failure. What is the etiology?].

The authors describe the finding of extensive tensive pneumoperitoneum which developed during distension therapy (CNP) in an immature neonate. The absence of another extraalveolar cumulation of air made the authors use PO2 analysis in the peritoneal air by means of a transcutaneous electrode. Because the PO2 rose after connection of the electrode to the catheter draining the abdominal cavity, the authors assumed a respiratory aetiology of the pneumoperitoneum and did not consider laparatomy. They assume that the above test may be valuable in the differential diagnosis between respiratory and gastrointestinal pneumoperitoneum in those instances where it is not possible to assess the aetiology of pneumoperitoneum unequivocally.

Humans↗

PubMed1992

[Massive systemic and intracranial air embolisms in a premature child with severe RDS syndrome treated with high-frequency oscillation ventilation].

The authors present a case of massive systemic air embolism with an unusual X-ray finding which developed during high-frequency oscillation ventilation (HFOV), paradoxically when minimal inflation pressures were used. The air was detected by X-ray not only in the systemic circulation but also intracranially (in the area of the cisterna magna, cerebral sinuses and intraventricularly). They draw attention to the fact that even the application of non-conventional ventilation methods does not rule out the development of this serious complication and they recommend, when this complications is suspected, to examine by X-ray also the cranium. This is the first report in the literature where intracranial embolization developed during HFOV.

Embolism, Air↗