Search PubMed⌕ Search

Biomedical subjects

A Nikolov

Publications and source records attributed to A Nikolov.

At least 91 records · Page 5Linked to original sources
PubMed1999

[Administration of exogenous surfactant in premature very low birth weight infants with RDS].

A retrospective study is carried out with the aim of establishing the effect from surfactant therapy on pulmonary function, survival and complication from intensive therapy on VLBWI with RDS. 67 premature infants below 1500 grams are included in the study divided in 3 groups: I gr.--27 babies treated with Corosurf; II gr.--16 babies treated with Exosurf; III gr.--24 control babies without surfactant. The results show that in spite of relatively lower gestational age and higher incidence of inborn infection in group I, Curosurf treated babies spend shortest time on mechanical ventilation and oxygen therapy showing lower incidence of BPD, IVH and mortality rate.

Case-Control Studies↗
PubMed1999

[Problems and outcome in very low birth weight infants, with three cases of babies under 700 grams].

Recent advances in neonatal medicine made reality the survival of newborn babies of extremely low weight and gestational age. This often provokes ethical problems in relation to high death rate, morbidity and neuro-developmental seguels. On the other hand it is usually impossible at birth to predict the presence and severity of future problems. We present the cases of three babies, where in spite of the most unfavourable factors connected to mother's condition, foetus and newborn, three healthy children were raised up. Their characteristics at birth are: 650 g--30 gestational weeks; 560 g--29 gestational weeks; 600 g--29 gestational weeks. In all of them intensive resuscitation and mechanical ventilation are started immediately after birth, two of them received prophylactic surfactant. Little by little, the problems arising from extremely low birth weight, faded away. All babies had grade I-II IVH which were totally resorbed. The first baby is three years old at the moment with were totally resorbed. The first baby is three years old at the moment with adequate for her age mental and neurologic development. The other two babies, resp. 9 and 3 months of age, are also developing normally. In conclusion, the possibilities for survival and raising up of babies of extremely low weight and gestational age are definitely increasing, requiring high qualification staff, modern technics and very large funds for diagnostics, monitoring and treatment.

Female↗
PubMed1999

[Use of the balloon catheter before induction of labor with oxytocin in cases with unfavorable pelvic score and premature delivery].

The purpose of this prospective work is to communicate the experience with preinduction treatment with Folly's catheter on the Pelvic score (Ps), labor and neonatal outcome in 52 cases in 27 to 34 wg, preterm premature labor and unfavourable cervix. The first control group consist of 24 pregnancies with the same characteristics but with favourable cervix at the begging of labor induction and the second control group include 31 cases with spontaneous premature labor. The Folly's catheter is introduced through the cervical canal and the bulb inflated with 75 ml of sterile normal saline. After the Foley's catheter dropped out the Ps is reassessed and proceed with oxytocin infusion. In the first control group with favourable cervix the induction of labor is only with oxytocin via infusion pump. More than half of all patients are treated with with tocolysis. The results show that for the period of tocolysis and/or PPROM there is significant improvement of the Ps (from 0.90 +/- 0.9 to 2.35 +/- 1.5). The change in the Ps doesn't depend on the g.w., the length of tocolysis or on the initial Ps. The balloon catheter improve the Ps from 2.35 +/- 1.5 to 6.24 +/- 1.3 for y period of 3 h 20 min (2 h 40 min to 4 h, 95% confidence). After the Foley catheter dropped out the duration of labor with oxytocin infusion is 6 h (5 to 7 h, 95% confidence) and is not different from this in the control groups. The time for the catheter to drop out, the achieved Ps and especially the effacement of the cervix are essential features in the prognosis of the difficulties in the labor process and the neonate state.

Case-Control Studies↗
PubMed1998

The Effect of Many-Body Interactions on the Sedimentation of Monodisperse Particle Dispersions

An experimental investigation was made of the sedimentation rate of low-charged monodisperse silica and polystyrene latex particle dispersions as a function of the particle volume fraction. It was found that the normalized sedimentation velocity U/U0, corrected for the effect of the two-body hydrodynamic interaction, increases with the particle volume fraction, which indicates that the degree of particle aggregation inside the dispersions increases with the particle volume fraction. This phenomenon results from attractive many-body hydrodynamic interactions between colloidal particles. It is reported for the first time that the many-body hydrodynamic interaction becomes important at the particle concentration of 6.5 vol% in monodisperse dispersions, and the many-body thermodynamic interaction is negligible at a low particle concentration, i.e., less than 15 vol%. The effect of many-body hydrodynamic interaction on the particle microstructure was also experimentally examined by using a nondestructive Kossel diffraction technique based on the principle of back-light scattering. It was found that the particle packing structure inside the dispersion initially becomes more ordered with the increase of the particle volume fraction. However, there is less increase in the particle ordering structure after 6 vol%. Furthermore, after the particle concentration reaches 10 vol%, the particle packing structure decreases to a value lower than that of 6 vol% due to the increased particle aggregation, as found in the sedimentation experiments. Predictions of a statistical thermodynamic model were compared with the experimental data on structure factors. It is found that particle dimerization occurs around 10 vol%, which agrees with the sedimentation results. Copyright 1998 Academic Press. Copyright 1998Academic Press

Journal Article↗
PubMed1998

[The use of Curosurf with premature infants--the prevention or treatment of the neonatal RDS].

A randomized clinical prospective study is carried out aiming to compare prophylaxis with Curosurf versus rescue treatment. 28 inborn VLBW I are included: 17 received Curosurf as prophylaxis and 11 controls, who received rescue treatment if indicated. Both groups are similar regarding mean body weight, mean gestational age, dosage of Curosurf, etc. Results underwent statistic analysis. Data from the study shows better effect from prophylaxis with Curosurf: smaller number of babies developed RDS and especially RDS grade III-IV (subsequently less babies needed a second dose of Curosurf); higher PaO2/FiO2 ratio; reduced duration of artificial ventilation and of oxygen therapy; reduced incidence of BPD. Results do not show statistically significant difference, but a tendency for ft. As a conclusion: prophylaxis with Curosurf leads to a decrease in the incidence and severity of RDS and to reduced duration of ventilation support and oxygen therapy.

Biological Products↗
PubMed1998

[Multiple pregnancy and microelements: zinc (preliminary report)].

The aim af the study was to define the concentration of zinc in sera of women with multiple pregnancies during the last trimester and to compare it with the values in normal pregnancies. The study included 12 women with gemini and 67 with single fetus pregnancies. A statistically significant decrease was found in the mean zinc concentration in twin pregnancies--8.1 +/- 1.72 mcmol/L compared to the mean values in normal pregnancies--10.5 +/- 1.90 mcmol/L (p < 0.001). Various mechanisms, possibly responsible for the stated changes, their relation to some complications of multiple pregnancy and delivery are discussed, as well as their prophylactics.

Analysis of Variance↗
PubMed1998

[The effect of antenatal corticosteroid prophylaxis in premature newborns with the use of surfactant therapy].

The study is retrospective aiming to elucidate the effect of antenatal corticosteroids (CS) for prevention of RDS in preterm deliveries, followed by surfactant therapy. 28 premature babies from 26 to 31 gest. weeks, receiving Curosurf at birth, were included in the study. They were divided in two groups: group A-17 babies of mothers with CS prophylaxis and group B-11 babies from deliveries without prenatal CS. All babies were followed for incidence and severity of RDS, duration of artificial ventilation and oxygen therapy. Although mean gestational age and body weight are lower in group A, incidence of severe RDS is lower (23.5% versus 36.4% in group B); duration of artificial ventilation with FiO2 > 0.60 and as a whole is smaller (mean 28.9 hrs and 186 hrs v/s 50.3 hrs and 228 hrs resp. in group B; p < 0.05), duration of oxygen therapy is shorter (mean 428 hrs v/s 540 hrs in group B; p < 0.05), smaller is the incidence of pneumothorax, IVH gr. III-IV, inborn infections and death rate although not statistically significant. The conclusion is made that antenatal use of CS improves lung function in premature babies and potentiates the effect of surfactant.

Betamethasone↗
PubMed1998

[Tumors in childhood and adolescence].

The trial present the results for the incidence and histology of tumours in patients below 18 years, examined at the State University Hospital Maĭchin Dom in Sofia for two consequent periods of 4 years each. An increase is registered in the incidence of neoplastic disease from 1.85% to 3.42%. There is no significant difference in hystological characteristics of the tumours when comparing I and II period: 85.7% versus 77.4% benign tumours (mucous cysts, dermoid ovarian cysts and polyps) and 14.3% versus 22.6% malignant tumours (ill differentiated teratomas, cystadenocarcinomas, dysgerminomas, ovarian embryocarcinomas and rhabdomyosarcomas). Accurate diagnostics requires detailed gynaecological examination, including a rectal one, vaginal probing, vaginal scopia, ultrasound, laparoscopy. Early discovery followed by surgery provides a possibility for adequate and definite treatment.

Adolescent↗
PubMed1997

Particle Structure and Stability of Colloidal Dispersions as Probed by the Kossel Diffraction Technique

A nondestructive Kossel diffraction technique based on the principle of back-light scattering was used to characterize the structure formation which results from the interparticle interactions in colloidal dispersions. Static structure factors, radial distribution functions, and average pair potentials, which characterize the particle packing structures in model systems of hydroxylate latex dispersions, were obtained. The effects of particle concentration and polydispersity on particle structuring and dispersion stability were also studied. Computer simulations based on the Ornstein-Zernike method were compared with the experimental results. Good quantitative agreement was observed.

Journal Article↗
PubMed1997

[An analysis of the indications for episiotomy in current obstetrical practice].

The aim is to analyze the accepted indications for episiotomy in nowadays practice. The investigations is retrospective for the period from April to May 1996. The material includes 459 term singleton pregnancy in vertex presentation and 46 cases of premature neonates with weight from 1300 to 1499 g. The results show high risk (77.1%) of episiotomy in nulliparous women. The multiparity, the length of second period and the high risk pregnancies have not effect on the use of episiotomy. The wight of the fetus is essential factor. The highest rate of episiotomy is at premature births (65.2%) followed by the group of neonates with weight over 4000 g (61.5%). The lowest rist of episiotomy is then the weight of newborn is between 2500 and 3800 g (21.8%). Almost hundred percent rate of episiotomy in operative vaginal and breech deliveries show that we accept the episiotomy as obligatory of these vaginal deliveries.

Adult↗
PubMed1997

[The results of the limited use of episiotomy in managing the second stage of labor].

The purpose is to asses the effect of restrictive use of mediolateral episiotomy on the spontaneous laceration of the low birth canal. The material includes 613 labors some of which gave birth with indication for episiotomy and control group of 441 retrospective cases with routine management of the second period of labor. The restrictive use of episiotomy decreases the rate from 45.6% in the routine practice to 32.8%. The reduced rate of episiotomy has as a consequent increase rate of second degree perineal laceration adn insignificant increase of vaginal lacerations. The management of restrictive and liberal use of mediolateral episiotomy has not effect on third and four degree perineal laceration, on the accessory tears of the vagina and on the rate of perineotomy. If from all labors are subtracted operative deliveries, surgical intervention for repairing the laceration of the birth canal and pathology of the placental period the rate of labors without any intervention is only 13.3%. Our results suggest that labor nowadays is operative activity.

Bulgaria↗