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H Lagercrantz

Publications and source records attributed to H Lagercrantz.

At least 55 records · Page 3Linked to original sources
PubMed1999

Randomised controlled trial of effect of terbutaline before elective caesarean section on postnatal respiration and glucose homeostasis.

AIM: To determine if terbutaline given to mothers before elective caesarean section facilitates neonatal respiration and metabolism. METHODS: A randomised controlled trial of 25 full term infants delivered by elective caesarean section was conducted. The mothers received a continuous infusion of terbutaline or saline 120-0 minutes before birth. Umbilical artery blood was collected at birth and analysed for blood gases and catecholamines. The lung function of each infant was assessed two hours after birth, and blood pressure, heart rate, blood glucose and body temperature were monitored until 24 hours of age. RESULTS: The infants of the treated mothers (n = 13) had significantly higher dynamic lung compliance (p < 0.001), lower airway resistance (p < 0.001), and respiratory frequency than control infants (n = 12). Blood glucose and adrenaline concentrations were significantly higher in the treated group (p = 0.0014 and p < 0.01). None of these infants had any clinical respiratory difficulties; there were two cases of transient tachypnoea in the control group. No negative side effects due to the terbutaline treatment were seen among the infants. The mothers felt no discomfort caused by the terbutaline infusion, although they bled more during surgery (p = 0.03). CONCLUSION: Stimulation of the beta adrenoceptors in utero with terbutaline infusion to the mothers promotes neonatal respiratory and metabolic adaptation after elective caesarean section.

Adrenergic beta-Agonists↗
PubMed1998

[Periventricular leukomalacia. I. Histological and pathophysiological aspects].

The term 'periventricular leukomalacia' (PVL) usually covers necrotic and/or gliotic lesions from perinatal origin occurring in the periventricular ring of telencephalic white matter. PVLs are found post-mortem in one third of brains from autopsies of premature infants; PVLs are diagnosed in 4 to 10% of infants born before 33 weeks of gestation and remaining alive more than 3 days after birth. PVL is very rare in at term infants. The proportion of PVLs from prenatal origin is estimated between one third and one half of cases. Recent progresses in neuroepidemiology, developmental neurobiology and imaging methods permit to revisit the pathophysiology of PVLs on a multifactorial basis. The final result of these multiple factors seem to be calcium influx due to glutamatergic overactivation triggered by cytokines, infection and inflammation, and deficit in neurotrophic factors. Periventricular topography can be explained by properties of intracerebral vascular wall at this stage of angiogenesis and by perfusion failure/hypoxia.

Humans↗
PubMed1998

[Periventricular leukomalacia and brain protection. II. Diagnosis, sequelae and neuroprotection].

The term 'periventricular leukomalacia' (PVL) usually covers necrotic and/or gliotic lesions from perinatal origin occurring in the periventricular ring of telencephalic white matter. Carrying motor and neuropsychological consequences, PVLs could be the most severe danger for very premature brains. Positive rolandic sharp waves recorded on EEG and precocious abnormally echogenous periventricular images on ultrasound suggest prospective periventricular cysts. Cystic periventricular cavitations certify the diagnosis of PVL. More subtle lesions of PVL do not reach the cystic grade and their diagnosis is confirmed by MRI. Treatment of infections is already available and potentially a tool for prevention. When the overwhelming glutamatergic signal has been triggered, neuroprotective agents turning off the excitotoxic cascade, including calcium blockers, growth factors and others, are promising therapeutic tools.

Humans↗
PubMed1998

Cooling and asphyxia differentially affect augmented noradrenaline turnover in the brain of the externalized rat foetus.

The object was to investigate the effect of various perinatal conditions particularly cooling and asphyxia on the noradrenaline (NA) turnover in the foetal rat brain. The ratios between the noradrenergic metabolite 3-methoxy-4-hydroxy phenyl-ethylene glycol-sulphate (MHPG) and noradrenaline were determined as indexes of NA-turnover in the cortex and the pons-medulla of the foetal rat brain using high pressure liquid chromatography (HPLC). Rat foetuses were externalized by caesarean section performed on a spinally anaesthesized highly pregnant rat mother. One uterine horn was used as control while the other was exposed to externalization, simulated uterine contractions, cooling or asphyxia. Externalization per se and simulated uterine contractions did not cause any significant change in the NA-turnover. Cooling at 25 degrees C for 20 min caused a significant increase in NA-turnover in the cortex while a significant decrease was observed after 10 min of asphyxia in both the cortex and the pons-medulla and after 15 min in the cortex. We conclude that externalization and simulated uterine contractions per se do not seem to affect the augmented NA-turnover at birth. Cooling caused an increase suggesting a potentiating role on NA-turnover in conjunction with the externalization. On the other hand NA-turnover was depressed by asphyxia, suggesting that the level of oxygen is important for NA neuron activity.

Animals↗
PubMed1998

Alleviation of the pain of venepuncture in neonates.

UNLABELLED: A recent study has shown venepuncture to be more effective and less painful than heel-lancing when a single blood test is performed in neonates [Larsson, Pediatrics (in press)]. The aim of the present study was to investigate the value of EMLA applied on the dorsum of the hand when sampling blood in neonates. METHODS: This was a controlled randomized and double-blinded study. One hundred and twenty neonates were randomly allocated to two groups, EMLA or placebo. Five hundred milligrams (0.5 ml) of EMLA or placebo was placed on the dorsum of the hand, covered with an occlusive dressing, and left in place for 60 minutes. For venepuncture, a needle measuring 0.9 x 40 mm was used. The two groups were also compared as regards the total time needed to complete the PKU test and the number of skin punctures required. The facial reaction was videotaped and later analysed by two blinded observers using the Neonatal Facial Coding System (NFCS). RESULTS: No side effects occurred, except for a temporary blanching or redness of the skin, which disappeared within minutes. Nociceptive response: After skin puncture, the NFCS scores were significantly lower in the EMLA group than in the placebo group (median 287 and 374, respectively). After the first skin puncture, a cry was recorded in 35/55 cases (64%) in the EMLA group and in 38/56 cases (68%) in the placebo group, this difference was not significant. The duration of the first cry was significantly shorter in the EMLA than in the placebo group (median 12 and 31 s, respectively). CONCLUSION: In comparison with a placebo, EMLA significantly reduces the pain caused by venepuncture on the dorsum of the hand and does not complicate puncture of the vein.

Anesthetics, Local↗
PubMed1998

Venipuncture is more effective and less painful than heel lancing for blood tests in neonates.

OBJECTIVE: Heel lancing has hitherto been the method of choice for screening tests of inborn errors of metabolism in neonates. Eutectic mixture of local anesthetic has little, if any, analgesic effect when applied to the heel of pre- and full-term infants. Today there seems to be no practical method that effectively alleviates the pain caused by heel lancing. The aim of this study was to investigate whether other methods, such as venipuncture of the dorsal side of the hand, are less painful and more efficient than heel lancing in neonates. METHODS: One hundred twenty healthy, full-term infants who underwent testing for phenylketonuria (PKU) were included in the study. They were randomized into three groups: a venipuncture group (VP) (n = 50), a heel-lance group with a small lancet (SL) (n = 50), or a large lancet (LL) (n = 20). Pain reactions were assessed by the Neonatal Facial Coding System (NFCS). The latency and duration of the first cry as well as the total screaming time was analyzed. The efficacy of the method was assessed by the time taken to complete the PKU test and number of times the skin had to be punctured. RESULTS: Nociceptive response. The NFCS scores after the first skin puncture were: VP, 247; SL, 333; and LL, 460. The NFCS scores were significantly lower in the VP than in the groups subjected to heel lancing. During the first 60 seconds after skin puncture, 44% of the infants cried in the VP group, compared with 72% and 85% in the SL and LL groups, respectively. Efficacy. A successful PKU test with only one skin puncture was performed in 86% of the VP group, but in only 19% in the SL group and 40% in the LL group. The total time needed to obtain the PKU blood sample was 191 seconds (median) in the VP group, 419 seconds in the SL group, and 279 seconds in the LL group. CONCLUSION: Venipuncture is more effective and less painful than heel lancing for blood tests in neonates.

Blood Specimen Collection↗
PubMed1997

Long-term influence of neonatal hypoxia on catecholamine activity in carotid bodies and brainstem cell groups of the rat.

1. In order to determine the long-term influence of neonatal hypoxia on catecholaminergic activity in peripheral arterial chemoreceptors and brainstem noradrenergic cell groups (A1, A2, A5 and A6), 1-day-old male rat pups were subjected to hypoxia (10% oxygen) for 6 days and then supplied with normal air. Control animals were kept at normoxia from birth. Rats were killed at either 3 or 8 weeks of age. 2. The content of dopamine and noradrenaline in carotid bodies of neonatally hypoxic rats was increased at both 3 and 8 weeks of age. 3. Noradrenaline turnover was selectively decreased in the caudal portion of A2 (located in the area of chemosensory afferent projection) at 8 weeks of age (-76 +/- 2%), while this turnover was unaffected in rostral A2 cells. Noradrenergic activity in A1, A5 and A6 was altered by neonatal hypoxia in an age-dependent fashion. 4. The data suggest that neonatal hypoxia induces long-term changes in the basal activity of the carotid body and brainstem noradrenergic cell groups. Such changes might contribute to neuronal regulation of the delayed respiratory, arousal and neural sequelae associated with neonatal hypoxia. These changes could also be involved in the early programming of respiratory and blood pressure control.

Animals↗
PubMed1997

Sudden infant death and prevalence of whooping cough in the Swedish and Norwegian communities.

UNLABELLED: Whooping cough (WC) has been suggested to be a trigger factor for sudden infant death (SID), the proposed mechanism being unrecognised hypoxaemic episodes. In contrast to Norway, Sweden ceased its immunisation programme against Bordetella pertussis (BP) in 1979. We investigated the relation between SID mortality and the prevalence of BP during 1983 to 1988, by month, in the two ethnically and socially similar, bordering countries adopting different strategies towards WC. In addition, the greater Stockholm area was analysed. For both countries the prevalence of BP was collected from monthly reports by regional health officers. SID mortality rates were provided by the Norwegian Central Bureau of Statistics and the SID registry at the Swedish National Board of Health and Welfare. The relation between SID mortality rate and prevalence of WC, by month, was analysed by linear regression. In addition, the consistency of seasonal fluctuations was investigated by analysing the covariance between average, pooled, monthly values of the two variables. SID mortality rate followed significantly the monthly prevalence of BP in Sweden (P < 0.01) and Stockholm (P < 0.0001) during the study period. In Norway there was a significant correlation only during the epidemic outbreak of WC (P < 0.05), but not for the whole study period. When controlling for seasonality a significant correlation remained in the urban area of Stockholm (P < 0.05). CONCLUSION: It is suggested that covariations between WC and SID mortality rate may be related to transmission rate and immunisation status of the investigated population.

Analysis of Variance↗
PubMed1997

Effect of extreme prematurity on renal dopamine and norepinephrine excretion during the neonatal period.

Dopamine (DA), produced in proximal tubular cells, is believed to be an important intrarenal natriuretic hormone. Experimental studies have shown that the natriuretic effect of DA is less pronounced in the fetal kidney. We have evaluated renal DA and norepinephrine (NE) in the neonatal period, using urinary excretion as an indicator of renally produced/released-catecholamines. In very low-birth-weight infants (25-30 weeks gestational age) there was an increase in urinary DA (pmol/mumol urinary creatine) and NE (pmol/mumol urinary creatinine) from 1 to 13 days postnatal age, despite a decrease in sodium excretion. Urinary NE correlated with plasma NE, whereas plasma DA was undetectable. In summary, NE excretion parallels plasma levels and could reflect the general sympathoadrenal activity, whereas DA is primarily of renal origin. Renal DA and NE increase in the first 2 weeks of life in immature infants. We conclude that the catecholamine system of the human kidney undergoes maturational changes postnatally.

Chromatography, High Pressure Liquid↗
PubMed1997

Adrenalectomy reduces the ability of newborn rats to gasp and survive anoxia.

The ventilatory response to anoxia in unanaesthetized rat pups of 1 and 8 days of age was studied. Ventilation was recorded by barometric plethysmography. During acute anoxia (100% N2), animals of both ages responded with hyperpnoea, primary apnoea, hypoxic gasping and secondary apnoea. After secondary gasping, occasional gasps occurred. If oxygen was administered during the gasping period, all animals survived through autoresuscitation. The duration of the period of hypoxic gasping was significantly longer in the 1-day-old animals. Adrenalectomy reduced the length of this period in both 1- and 8-day-old animals. In a second series of experiments, the effect of adrenergic antagonists on autoresuscitation was examined. Pretreatment with the non-selective alpha-receptor antagonist phentolamine reduced the duration of gasping in 1-day-old rats, but prolonged this duration in 8-day-old rats. The non-selective beta-receptor antagonist propranolol did not affect the duration of gasping in 1-day-old rats, whereas it prolonged this period in the older animals. We conclude that proper duration of gasping during anoxia is dependent on intact adrenal function and that the adrenal glands therefore play an important role in autoresuscitation from anoxia during postnatal life. The underlying mechanism appears to involve alpha-adrenergic receptors.

Adrenalectomy↗
PubMed1997

The decline in the incidence of SIDS in Scandinavia and its relation to risk-intervention campaigns. Nordic Epidemiological SIDS Study.

A prospective case-control study of sudden infant death syndrome (SIDS) in Norway, Denmark and Sweden between September 1, 1992 and August 31, 1995 comprised 244 cases and 869 matched controls. After the introduction of risk-intervention campaigns, the SIDS incidence decreased from 2.3/1000 live births in Norway, 1.6 in Denmark and 1.0 in Sweden to 0.6/1000 or fewer in all the Scandinavian countries in 1995. The decrease paralleled a decline in the prone sleeping position and there was an accompanying parallel fall in total postneonatal mortality in all three countries. Thus, the risk-reducing campaigns for SIDS have been successful not only in Norway and Denmark, starting from relatively high incidences, but also in Sweden, starting from a low incidence. During the study period, a gradual increase was observed for the effects of prone sleeping, smoking and bottle-feeding as risk factors for SIDS.

Case-Control Studies↗
PubMed1997

Neonatal care of very-low-birthweight infants in special-care units and neonatal intensive-care units in Stockholm. Early nasal continuous positive airway pressure versus mechanical ventilation: gains and losses.

Very-low-birthweight (VLBW) infants are usually intubated at birth and mechanically ventilated at neonatal intensive-care units (NICUs). The objectives of this study were to evaluate the use of early nasal continuous positive airway pressure (NCPAP) in a regional cohort and to determine to what extent VLBW infants need transfer to a regional NICU from special-care units (SCUs) that primarily use early NCPAP for respiratory care. We compared the outcome for infants at SCUs and NICUs in Stockholm County, Sweden, from 1988 to 1993. All infants with birthweights of less than 1501 g were included in this study (n = 687). Fifty-nine per cent of the infants (400/687) were supported using only supplemental oxygen or NCPAP. Of these, 170 (25%) received only supplemental oxygen and 230 (34%) were supported only by NCPAP. A total of 350 (51%) infants received early NCPAP. Of these infants, 120 (34%) later required mechanical ventilation. Only 167 (24%) infants received mechanical ventilation from the beginning Failure of NCPAP was significantly associated with the presence of respiratory distress syndrome. A total of 161/412 (39%) infants were transferred from SCUs to NICUs. Of infants < or = 26 weeks' gestation and infants > 26 weeks, 71% and 34% were transferred, respectively. Total mortality was 16%. The mortality for transfers was 20% compared to an overall mortality in SCU and NICU infants of 9% and 15%, respectively. The overall incidence of intraventricular haemorrhage (IVH), grade III-IV was 8%, periventricular leucomalacia (PVL) grade I-IV was 7%, retinopathy of prematurity (ROP) requiring cryotherapy was 4.3% and chronic lung disease (CLD) was 14%. There were significant differences in the incidence IVH, PVL, CLD and ROP between SCU and NICU infants in matched gestational age groups. In conclusion, infants with a gestational age of 27 weeks or more may often be adequately cared for at SCUs without mechanical ventilation by using early NCPAP. However, infants with a gestational age of 26 weeks or less should be transferred to tertiary-care centres preferably before birth, because they will often require mechanical ventilation.

Gestational Age↗
PubMed1997

The Stockholm Neonatal Project: neonatal mortality and morbidity at the Children's Centre, Karolinska Hospital.

Two hundred and ninety-one very-low-birth-weight (VLBW) infants were studied prospectively during the period of 1988-1993. All inborn VLBW infants and most of the VLBW infants born in Greater Stockholm and requiring neonatal intensive care were included in this study. The overall mortality was 17.5% and the mortality in the group with the lowest gestational age at birth, i.e. 23-24 weeks, was 25%. The mortality for boys was higher than for the girls. The mode of delivery, i.e. vaginal versus caesarean section and multiple birth, did not seem to affect the mortality rate. Respiratory insufficiency and/or cerebral complications were the most common cause of neonatal death. Patent ductus arteriosus was found in 35% of the infants, of whom 43% needed surgical ligation. One-third of infants with retinopathy of prematurity (30/92) required cryotherapy.

Cause of Death↗