Haemodynamic changes during positive-pressure ventilation in children.

BACKGROUND: Positive-pressure ventilation may alter cardiac function. Our objective was to determine with the use of impedance cardiography (ICG) whether altering airway pressure modifies the central haemodynamics in mechanically ventilated children with no pulmonary pathology. Central venous saturation (S(cv)O(2)) was measured as an indicator of tissue perfusion. METHODS: Twelve children between 7 and 65 months of age, requiring mechanical ventilation as a consequence of a non-pulmonary disease, were enrolled in the study. All patients had a central venous line as a part of their routine management. Using pressure controlled ventilation (PCV) the baseline PEEP value of 5 cmH(2)O (P(b5)) was increased to 10 cmH(2)O (P(i10)) and then to 15 cmH(2)O (P(i15)). After P(i15), PEEP was decreased to 10 (P(d10)) and then to 5 cmH(2)O (P(d5)). Each time period lasted 5 min heart rate (HR), mean arterial blood pressure (MABP), central venous pressure (CVP), end-tidal carbon dioxide (ETCO(2)), mean airway pressure (P(aw)), stroke volume index (SVI), cardiac index (CI) and central venous oxygen saturation (S(cv)O(2)) were recorded at the end of the five periods. RESULTS: The values of CI did not change when 10 and 15 cmH(2)O of PEEP were applied. Elevation of PEEP and thus P(aw) caused slight but not significant reductions in SVI and S(cv)O(2) as compared to the baseline (T(b5)). After reducing PEEP in T(d5) we found statistically significant elevations of SVI and CI, as compared to T(i15) heart rate, ETCO(2) and MABP remained unchanged. CONCLUSION: We did not find significant haemodynamic changes following PEEP elevation in ventilated children, as measured using impedance cardiography. Reducing the value of PEEP to 5 cmH(2)O resulted in statistically significant SVI elevations. The values of S(cv)O(2) remained unaffected.

Use of impedance cardiography to monitor haemodynamic changes during laparoscopy in children.

METHODS: Haemodynamic changes were measured noninvasively using impedance cardiography (ICG) in 30 ASA I children during laparoscopic varicocelectomy under general anaesthesia. After induction and intubation, mechanical ventilation was started, then pneumoperitoneum (PP) was created. During the course of anaesthesia, values of endtidal CO2 pressue (PECO2), peak inspiratory airway pressure (PIP), heart rate (HR), mean arterial blood pressure (MABP), stroke volume index (SVI), cardiac index (CI) and systemic vascular resistance index (SVRI) were recorded at 1 min intervals. We analysed four periods: T1, before induction; T2, after induction; T3, during PP; T4, after desufflation of PP until awake. RESULTS: After induction of anaesthesia a significant reduction of HR, MABP and CI was recorded. Creating PP together with the use of a 15 degrees head down tilt resulted in a further drop in CI, mainly caused by the reduction of SVI, and an elevation of MABP and SVRI. We measured a 25% total decrease of CI. CONCLUSION: Our patients tolerated this significant reduction of cardiac output well. We have demonstrated that ICG can be used to track the haemodynamic changes caused by PP in children, and suggest that this type of monitoring is useful in this group of age during laparoscopy.

Preparation of selenium yeasts I. Preparation of selenium-enriched Saccharomyces cerevisiae.

Selenium (Se) is an essential micronutrient for human and animal organisms. Organic selenium complexes and selenium-containing amino acids are considered the most bioavailable. Under appropriate conditions yeasts are capable of accumulating large amounts of trace elements, such as selenium, and incorporating them into organic compounds. It has been found that introduction of water-soluble selenium salt as a component of the culture medium for yeasts produced by conventional batch processing results in a substantial amount of selenium being absorbed by the yeast. Using a culture medium supplemented with 30 microg/mL sodium-selenite added during the exponential growth phase results in selenium-accumulation in the range of 1200-1400 microg/g dried baker's yeast (Saccharomyces cerevisiae) measured by ICP-AES method. In our previous studies it was shown that higher amounts of sodium-selenite in the culture medium have a strong inhibitory effect on the growth of this yeast. As a consequence of variations in cultivation conditions we obtained selenium yeast with different inorganic selenium content. The most important parameters influencing incorporated forms of selenium are pH value and dissolved oxygen level in the culture medium, and depending on these the selenium consumption rate of the yeast. A 0.40-0.50 mg/g h-1 specific selenium consumption rate was found to be appropriate to obtain selenium-enriched bakers' yeast of a high quality. Under suitable conditions the undesirable inorganic selenium content of the yeast could be suppressed to as low as 5-6% at the expense, however, of approximately a 20% decrease in the final biomass.

[Use of clozapine during pregnancy]. / Clozapine alkalmazásáról terhesség során.

The authors deal with the use of closapine during pregnancy. In their cases after the use of closapine during pregnancy, healthy children were born.

[Dopamine, noradrenaline and serotonin levels in amniotic fluid during the second trimester in normal and pathologic pregnancy]. / A magzatvíz dopamin, noradrenalin és szerotonin értékei a terhesség második trimeszterében, normális és kóros kimenetelü terhességekben.

Authors measured the dopamine (DA), noradrenaline (NA) and serotonin (5-HT) contents of amniotic fluid between 19 and 21 weeks with fluorimetric method. The amniotic fluid samples were obtained by transabdominal amniocenteses performed due to elevated maternal serum-alphafetoprotein levels and suspect ultrasound findings. They considered as normal values the average of 30 amniotic fluid samples obtained from pregnant women who gave birth to healthy babies at term. The mean values (mean+SE) of normal cases were 136.6 + 20.2 nmol/l for DA, 29.5 + 9.4 nmol/l for NA and 72.6 + 4.9 nmol/l for 5-HT. Against these values, in cases of open spina bifida the level of NA showed no significant difference, the DA level was higher (p < 0.05) and the 5-HT level was also higher (p < 0.001). The DA level was found higher (p < 0.05) in cases of intrauterine retardation as well, however there was no difference in the NA and 5-HT levels in these cases. In cases of preterm deliveries, none of the above parameters showed differences. Authors suggest that in cases of spina bifida the measurement of 5-HT in the amniotic fluid can be a complementary diagnostic method. They also state that no prognosis about the outcome of pregnancies can be expected from such examinations.

The diagnostic value of maternal pregnancy-specific beta 1-glycoprotein in threatened abortion.

208 serum SP1 measurements have been made in 124 women admitted at the 8th to 20th gestational week for the treatment of threatened abortion. Pregnancy ended in abortion in 85,6 p.c. of the cases with pathological serum levels, while only 16,9 p.c. of the women with normal serum concentration aborted. The results demonstrate the prognostic value of serum SP1 estimations in early pregnancy.