PubMed Health⌕ Search

Biomedical subjects

H Ekblad

Publications and source records attributed to H Ekblad.

18 recordsLinked to original sources
PubMed1992

Atrial natriuretic peptide in the preterm infant. Lack of correlation with natriuresis and diuresis.

We assessed the relation of atrial natriuretic peptide (ANP) to renal function on postnatal day 2 and day 5 in preterm infants. Plasma ANP concentration was measured by radioimmunoassay in two groups of preterm infants: group 1, gestational age less than 30 weeks, n = 10; and group 2, gestational age 30-34 weeks, n = 11. The identity of the immunoreactivity as ANP-28 was confirmed by HPLC. Plasma ANP was significantly higher in group 1 than in group 2 on day 2 and day 5 (p < 0.01) and ANP concentration decreased by day 5 in both groups (group 1, p < 0.01; group 2, p < 0.02). The results showed no correlation between plasma ANP concentration and urinary sodium excretion or creatinine clearance, which may be due to a blunted renal response to ANP, but other factors may be involved also. We conclude that preterm infants are able to release large amounts of ANP, but a high plasma ANP concentration does not correlate directly with renal regulation of sodium and water balance.

Atrial Natriuretic Factor↗
PubMed1992

Intracellular pH regulation in cultured renal proximal tubule cells in different stages of maturation.

This study examines the ontogeny of cellular pH regulation in renal proximal tubule cells (RPTC). RPTC from 8- to 40-day-old Sprague-Dawley rats (RPTC-8 to RPTC-40) were studied after 48 h of primary culture. Intracellular pH (pHi) was measured by quantitative fluorescence microscopy using 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein. Recordings were made under basal conditions and after imposing a cytoplasmic alkalosis and acidosis using 15 mM NH4+ salt. The net recovery rate (dpHi/dt) from intracellular acidosis increases significantly between 10 and 12 days of age from 0.39 +/- 0.04 to 0.54 +/- 0.06 pH units/min (P < 0.05, n = 10 vs. 6). This increase can be completely accounted for by an increase in the rate of amiloride (100 microM)-inhibitable Na(+)-H+ exchange (0.29 +/- 0.04 vs. 0.42 +/- 0.05 pH units/min, P < 0.05, n = 6 vs. 6). The rate of Na(+)-H+ exchange increases similarly in RPTC-10 and RPTC-40 when the transmembrane Na+ gradient is increased by Na+ depleting the cells (48 and 49%, respectively). The amiloride-insensitive recovery is Na+ independent and insensitive to 4-acetamido-4'-isothiocyanostilbene-2-2'-disulfonic acid (SITS, 500 microM) (range 0.08-0.14 pH units/min). The net recovery rate from intracellular alkalosis is significantly lower in RPTC-10 than in RPTC-40 (0.16 +/- 0.02 vs. 0.28 +/- 0.02 pH units/min, P < 0.01, n = 4 vs. 5). SITS (500 microM) inhibits the recovery by 27 +/- 8 and 26 +/- 9%, respectively, whereas amiloride has no effect.(ABSTRACT TRUNCATED AT 250 WORDS)

4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfo↗
PubMed1992

Mode of delivery, plasma catecholamines and Doppler-derived cardiac output in healthy term newborn infants.

Umbilical cord arterial and venous concentrations of epinephrine, norepinephrine and the catecholamine metabolites 3,4-dihydroxyphenylglycol and 3,4-dihydroxyphenylacetic acid were determined in 41 healthy newborn infants delivered vaginally, vaginally with epidural analgesia, by cesarean section under general anesthesia or by cesarean section under epidural anesthesia. Doppler-derived cardiac output and arterial blood pressure were repeatedly measured during the first 48 h of life. There were fairly small differences in umbilical arterial and venous plasma concentrations of epinephrine and norepinephrine between the groups, with the highest levels of norepinephrine in infants delivered vaginally without analgesia (about 10 times as high as in the cesarean, general anesthetized group). No significant differences were found in the metabolite concentrations. Doppler-derived cardiac output and heart rate decreased in all groups during the study period and, in spite of increased catecholamine levels in the vaginally delivered infants, the differences between the groups were marginal. Healthy term infants with no signs of asphyxia were well prepared for a normal hemodynamic adaptation irrespective of mode of delivery or mode of obstetric anesthesia/analgesia.

Analgesia, Epidural↗
PubMed1992

Sympathoadrenal activity in preterm infants during the first five days of life.

We measured plasma concentrations of epinephrine (E), norepinephrine (NE), 3,4-dihydroxyphenylacetic acid (DOPAC), and 3,4-dihydroxyphenylglycol (DHPG) as well as urinary concentrations of metanephrine (M), normetanephrine (NM) and 3-methoxy-4-hydroxymandelic acid (MOMA) on day 2 and day 5 in preterm infants; gestational age less than 30 weeks (G less than 30; n = 16) and gestational age 30-34 weeks (G 30-34; n = 19). Concentrations of E (0.00-2.28 nmol/l) and NE (0.6-9.1 nmol/l) in plasma were much lower than those previously reported during preterm and term delivery. The E:NE ratio decreased from 1:10 on day 2 to 1:30 on day 5, and the M:NM ratio decreased from 1:4 on day 2 to 1:8 on day 5, indicating relatively higher catecholamine secretion from the adrenals than from the sympathetic nerve terminals in preterm infants during postnatal adaptation. Plasma concentrations of DOPAC and DHPG were significantly higher in G less than 30 than in G 30-34 (DOPAC, p = 0.0494; DHPG, p = 0.0092), probably relating to a low urinary excretion rate of catecholamine metabolites in infants in G less than 30. Plasma and urinary concentrations of catecholamines and their metabolites varied considerably, and no significant correlations to postnatal events could be demonstrated.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1992

Renal function in preterm infants during the first five days of life: influence of maturation and early colloid treatment.

We measured the influence of maturation and early freshly frozen plasma infusion (FFP) on renal function (day 2 and day 5) in preterm infants in intensive care; they were divided into two groups, those with gestational ages less than 30 weeks (G less than 30) and those with gestational ages of 30-34 weeks (G 30-34). A total of 35 infants was studied. The infants were randomly assigned to one of two treatment groups, one receiving FFP, the other not, yielding four study groups; G less than 30 and no FFP (8 infants), G less than 30 and FFP (8 infants), G 30-34 and no FFP (9 infants) and G 30-34 and FFP (10 infants). The infants in the two FFP groups received FFP 10 ml/kg on days 1-3. FFP did not significantly influence creatinine clearance (CCr) or the urinary sodium excretion rate either in G less than 30 or G 30-34. CCr was significantly lower (p less than 0.001) and fractional urinary sodium excretion significantly higher (p less than 0.002) in infants of G less than 30 than in infants of G 30-34. Infants of G less than 30 had significantly higher plasma potassium concentrations (p less than 0.01) than infants of G 30-34. Despite the low CCr and the high urinary sodium excretion rate, infants of G less than 30 had stable fluid and electrolyte balance.

Aging↗
PubMed1991

Extracellular volume in preterm infants: influence of gestational age and colloids.

We assessed the effect of fresh frozen plasma (FFP) on extracellular volume (ECV) during the first few days of life in two groups of preterm infants, group 1 (gestational age less than 30 weeks) and group 2 (gestational age 30-34 weeks). The infants were randomly assigned to one of two treatment groups, one receiving FFP, the other not; group 1 infants receiving no treatment (n = 8) and group 1 infants receiving FFP (n = 11), and group 2 infants receiving no treatment (n = 9) and group 2 receiving FFP (n = 10). FFP was given at a dose of 10 ml/kg daily during a two-hour period for the first three days of life. ECV was measured on day 1 before FFP was given and on day 4 by the distribution of bromide. There was a significant correlation between birth weight and initial ECV (r = 0.85, P less than 0.001). In group 1 ECV was significantly higher than in group 2 (P less than 0.02). In group 1 receiving no treatment mean weight loss and mean decrease in ECV were equal (84 g/kg and 78 ml/kg, respectively), but no correlation between the two parameters could be found (r = 0.68, P = 0.06). In the other study groups, mean weight loss was higher than mean decrease in ECV, with no correlation between weight loss and change in ECV.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗
PubMed1991

Estimation of extracellular fluid volume by bromide dilution in infants less than 1000 grams birth weight.

We measured extracellular fluid volume by bromide dilution within 12 h of birth in 32 infants less than 1000 g birth weight. Mean (+/- S.D.) birth weight and gestational age were 763 +/- 123 g and 26 +/- 1 week, respectively. Mean extracellular fluid volume was 360 +/- 86 ml (477 +/- 107 ml/kg). These results are similar to extracellular fluid volume estimates from previous carcass analysis data. Wide variability is observed with both methods suggesting that biologic variability may be important.

Body Weight↗
PubMed1991

Grading of left-to-right shunting ductus arteriosus in neonates with bedside pulsed Doppler ultrasound.

A nonimaging pulsed Doppler technique was used to grade the magnitude of flow in left-to-right shunting ductus arteriosus. The results were compared with those obtained with a color Doppler flow mapping technique. The correlation between the grading results by these two methods was 0.91 (p less than 0.01). To determine hemodynamic influence of left-to-right shunting ductal flow, simultaneous measurements of Doppler-derived cardiac output were done. Results showed significantly higher cardiac output in infants with grade III shunting than in infants with grade 0 and grade I shunting. The nonimaging pulsed Doppler ultrasound technique used in the present study proved to be a clinically useful and accurate grading system of left-to-right shunting at the ductal level. The simple grading system with nonimaging Doppler is a valuable adjunct to the color Doppler flow mapping technique. It allows a regular evaluation of ductal flow as well as cardiac output.

Cardiac Output↗
PubMed1987

Water, sodium and acid-base balance in premature infants: therapeutical aspects.

One of the main targets of fluid therapy in premature infants is to avoid variations in osmolality, which mainly means providing a stable sodium, glucose, and acid-base balance. Water, sodium, and acid-base balance were measured in 20 infants appropriate-for-gestational age with a gestational age less than or equal to 34 weeks. The infants were randomly assigned to one of two treatment groups. Fluid intake was restricted and air humidity in the incubator was high in order to minimize insensible water loss. Sodium intake in Group 1 was 2 mmol/kg/day and consisted of sodium chloride. Sodium intake in Group 2 was 4 mmol/kg/day and consisted of both sodium chloride and acetate. Weight loss was appropriate in both groups. In the high sodium intake group there was a tendency towards a more stable plasma sodium concentration than in the low sodium intake group. The use of sodium acetate was efficient and practical as normal acid-base balance was maintained. The protocol with restricted fluid intake (1st day 50 ml/kg, 2nd day 70 ml/kg, 3rd day 90 ml/kg, and 4th day 110 ml/kg), high air humidity, a sodium supply of 3 to 4 mmol/kg/day, and a slow correction of metabolic acidosis with sodium acetate, yields suitable guidelines in planning fluid and electrolyte therapy in premature infants less than or equal to 34 weeks' gestation.

Body Weight↗
PubMed1987

Stable glucose balance in premature infants with fluid restriction and early enteral feeding.

Hyperglycemia readily develops during intravenous glucose administration in premature infants. In this study glucose homeostasis was measured in 24 infants appropriate-for-gestational age with a gestational age between 27 and 34 weeks and a birthweight between 1,150 and 2,610 g. The infants were randomly assigned to one of two treatment groups. Fluid intake consisted of intravenous infusion of 5% glucose in Group 1 and 10% glucose in Group 2, and increasing amounts of human milk from the first day of life. The infants were treated in incubators with high air humidity in order to minimize insensible water loss and total fluid intake was restricted. The fluid restriction and early enteral feeding decreased the total amount of glucose given parenterally and thereby the risk of hyperglycemia. Glucose homeostasis was efficiently maintained in both groups and under the conditions described hydration by intravenous infusion of 5% and 10% glucose appear equally well tolerated.

Enteral Nutrition↗
PubMed1987

Postnatal changes in colloid osmotic pressure in premature infants: in healthy infants, in infants with respiratory distress syndrome, and in infants born to mothers with premature rupture of membranes.

Colloid osmotic pressure (COP) of blood plasma during the first 4 days of life was measured in 63 neonates: 16 healthy preterm infants, 36 infants with respiratory distress syndrome (RDS), and 11 infants born to mothers with premature rupture of membranes. The relation between COP and total protein content of blood was significant in all groups over times from 1-3 h to 96 h. COP rose significantly by the age of 3 h compared to COP of umbilical cord plasma in all groups investigated. Infants with RDS showed a significant increase in COP during the investigation period. In healthy preterm infants the increase was less significant. In infants with RDS there was a negative correlation between changes in COP and body weight not seen in the other groups investigated. COP in neonates seems to reflect the compartmentation between vascular and interstitial spaces. Measurement of COP could be clinically useful in assessing hemodynamic adaptation after birth and also in assessing edema formation and water balance in infants with RDS.

Birth Weight↗
PubMed1986

C reactive protein in the evaluation of febrile illness.

We studied prospectively 154 febrile children to determine the diagnostic value of the quantitative serum C reactive protein concentrations (CRP). Children with acute otitis media, acute tonsillitis, or treated with antibiotics during the two previous weeks and infants less than 2 months of age were excluded. Ninety seven children were from private paediatric practice and 57 were patients who had been admitted to hospital. The comparison group consisted of 75 children with confirmed bacterial infections whose CRP values were recorded retrospectively. In the study group 35 (23%) children had a confirmed viral infection, 92 (59%) had a probable viral infection as judged from the clinical picture and outcome of the illness, and 27 (18%) had a bacterial or probable bacterial infection. When the duration of the disease was more than 12 hours and the CRP value less than 20 mg/l, all children had a confirmed or probable viral infection. Nine children (one from the study group and eight from the comparison group) were found to have a septic infection and a CRP value of 20 mg/l or less. In all these cases, however, the duration of the symptoms was less than 12 hours. In addition CRP less than or equal to 20 mg/l was found in five (14%) children with urinary tract infection in the comparison group. CRP values of 20-40 mg/l were recorded in children with both viral and bacterial infections. A CRP value greater than or equal to 40 mg/l detected 79% of bacterial infections with 90% specificity. Our data show that determination of serum CRP concentrations is a valuable tool in evaluating children who have been ill for more than 12 hours.

Adolescent↗
PubMed1985

Slow sodium acetate infusion in the correction of metabolic acidosis in premature infants.

The treatment of metabolic acidosis is one of many problems encountered in the premature infant during the first days of life. In this study, 11 infants with gestational ages of no more than 34 weeks were given sodium acetate as a continuous infusion from the first day of life. The daily sodium supply was set at 3 mEq/kg. The arterial serum pH was less than 7.30 in infants at the following ages: 1 to 3 hours, four; 24 hours, two; 48 hours, one; and 72 hours, one. The base deficit was calculated to be less than 5 in four infants at the age of 1 to 3 hours, in one infant at 24 hours, in one infant at 48 hours, and in no infants at 72 hours. The serum sodium concentrations were normal. The continuous infusion of sodium acetate seems to be suitable for the slow correction of metabolic acidosis, and the daily sodium supply of 3 mEq/kg gives a stable serum sodium concentration in the premature infant with a gestational age of no more than 34 weeks.

Acetates↗
PubMed1985

The monitoring of serum chloramphenicol levels in children with severe infections.

Serum chloramphenicol levels were evaluated in 52 children with severe infection treated intravenously with chloramphenicol succinate and orally with chloramphenicol palmitate, chloramphenicol monostearoylglycolate or chloramphenicol in capsules. Effective serum levels were recorded with all chloramphenicol preparations. The variability was largest with chloramphenicol monostearoylglycolate. In a case of neonatal Escherichia coli meningitis good serum levels of chloramphenicol were achieved with chloramphenicol palmitate orally, supporting the view that oral chloramphenicol palmitate can be used to treat serious infections in this age group. Our data and those in the literature show that monitoring of serum chloramphenicol levels in neonates is necessary. After the neonatal period monitoring of serum chloramphenicol levels is useful in avoiding too high concentrations. On the other hand, toxic effects of high concentrations can be recognized from reticulocyte and haemoglobin, neutrophil and platelet counts, which should be performed every three to four days.

Adolescent↗
PubMed1985

Colloid osmotic pressure of umbilical cord plasma in healthy and sick newborn infants.

Colloid osmotic pressure of umbilical cord plasma was measured in 242 healthy infants, in 34 infants with respiratory distress syndrome (RDS), in 18 infants with asphyxia, in 13 infants who were small for gestational age, in 15 infants born to mothers with diabetes mellitus, and in 18 infants born to mothers with pregnancy-induced hypertension. In healthy infants, colloid osmotic pressure correlated highly significantly with umbilical cord blood total protein level, gestational age, and birth weight. In infants with RDS, no correlation between colloid osmotic pressure and gestational age or birth weight was found. Infants with RDS and gestational age between 36 and 38 weeks had significantly lower colloid osmotic pressure than healthy infants, whereas colloid osmotic pressure of infants with RDS and gestational age between 32 and 35 weeks did not differ from that of healthy infants of corresponding gestational age. Healthy term infants delivered by cesarean section had significantly lower colloid osmotic pressure than infants delivered vaginally. Infants with asphyxia had significantly higher colloid osmotic pressure than healthy infants. Colloid osmotic pressure is related to the lung maturity of the near-term and term neonate. Infants with a colloid osmotic pressure greater than 16 mm Hg are unlikely to develop RDS.

Asphyxia Neonatorum↗
PubMed1984

Gastric aspirate L/S ratio and umbilical cord blood total protein as predictors in RDS.

Gastric aspirate L/S ratio and cord blood protein concentration were measured in 150 newborn infants, 33 of whom developed respiratory distress syndrome (RDS). 46.6% of the infants with low gastric aspirate L/S value (less than or equal to 3) and 33.3% of the infants with serum protein of less than or equal to 46 g/l developed RDS. The sensitivity of both parameters was 81.8%. Combination of these two methods yielded a higher predictive value (62.2%) but decreased the sensitivity (69.7%). The patterns of phospholipids reflect lung maturity, but also serum protein levels indicating overall maturity and the osmotic powers of microcirculation may be of diagnostic value in featuring developing RDS.

Blood Proteins↗