Haemodynamic features during high-frequency oscillatory ventilation in preterms

Aim: To compare the haemodynamic status during high-frequency oscillatory ventilation and conventional mechanical ventilation in very preterm infants with respiratory distress syndrome. Methods: Thirty-two neonates of less than 30 wk gestation randomly assigned to high-frequency oscillatory ventilation (n = 15) or conventional mechanical ventilation (n = 17) had three echocardiographies and one cerebral Doppler-echography under the same ventilation during the first 48 h of life. Results: Mean airway pressure was 2 cm H[Formula: See Text]O higher in infants ventilated with high-frequency oscillatory ventilation at the different echocardiographies. Comparable right ventricular indexes were observed in the two groups. Reduction of the ductus arteriosus diameter and ductal closure were significant only in neonates ventilated conventionally. Left ventricular performance and left ventricular contractility did not differ between the groups. The high-frequency group had lower end diastolic velocity and a higher resistance index in the anterior cerebral artery.

Conclusion: Compared with conventional mechanical ventilation, high-frequency oscillatory ventilation was achieved without altering cardiac function. However, the inability of the left ventricle to improve its performance in the presence of a significant ductal shunt suggests a narrow range of optimal pressures under this ventilatory mode.     

Vasopressin in catecholamine-resistant septic and cardiogenic shock in very-low-birthweight infants

AIM: To evaluate vasopressin as a rescue therapy in catecholamine-refractory septic and cardiogenic shock in very-low-birthweight (VLBW) infants. METHODS: Prospective assessment of vasopressin therapy in three VLBW infants with catecholamine-refractory septic shock (24 + 6 wk, 600 g) and cardiogenic shock (26 + 1 wk, 890 g; 26 + 1 wk, 880 g) at a university hospital. RESULTS: Adequate systemic arterial blood pressure could only be restored after vasopressin administration as a continuous infusion over a 36-h period in the preterm suffering from septic shock; in the two neonates with cardiogenic shock, only a transient stabilization in mean arterial pressure was observed, which did not impact on the poor prognosis. CONCLUSION: Although vasopressin appears to be a suitable rescue therapy in catecholamine-resistant septic shock in VLBW infants, further evaluation in controlled clinical trials is warranted.     

International survey on diagnosis and management of hypotension in extremely preterm babies

Hypotension is a commonly diagnosed and treated complication of extremely low gestational age newborns (ELGAN), but enormous variation in diagnosis, management and clinical practice has been documented. We sought to evaluate practice regarding the management of hypotension in ELGANs and developed a web-based questionnaire addressing diagnosis, intervention thresholds and modes of treatment of hypotension in ELGANs. We received 216 completed questionnaires from respondents in 38 countries. Most responses (83 %) were from specialist units where, together, over 26,000 very low birth weight (VLBW) infants are cared for annually. The majority (73 %) defined hypotension as a mean blood pressure (BP) in mmHg less than the gestational age in weeks. Sixty percent assessed the circulation with additional methods; echocardiography was the most commonly used (74 %), with left ventricular output and fractional shortening the two most common measurements made. The majority (85 %) used volume administration as the initial intervention. Dopamine was the inotrope most commonly used initially (80 %). If the initial inotrope therapy failed, dobutamine was the most popular second-line treatment (28 %). Delayed cord clamping was used at 51 % of the centres. Conclusion: The definition of hypotension in ELGANs continues to follow traditional standards. Functional echocardiography is now used to assess the circulation at many centres. Volume expansion and dopamine remain the most frequently used therapies.     

Postnatal and postprandial changes in plasma concentrations of glicentin in term and preterm infants

Aim: To examined the changes in basal plasma concentrations of glicentin in developing children and the postnatal and postprandial changes in plasma glicentin levels in infants. Methods: Glicentin, an active component of enteroglucagon, is considered to have a significant trophic action on the intestinal mucosa. Fasting plasma concentrations of glicentin in healthy children and in term and preterm infants were measured before and 30 min after feeding during the first 14 d of life. Results: Plasma basal concentrations of glicentin in children under 1 y of age were significantly higher than those in children aged 1 to 15 y. Plasma basal concentrations of glicentin at 5 or 6 d (2496 and 2190 pg/ml) and at 14 d (2987 and 2817 pg/ml) after birth were significantly higher than those at 1 or 2 d (1098 and 1240 pg/ml) after birth in normal birthweight (NBW) and low-birthweight (LBW) infants. There was no significant difference in the glicentin level between infants at 1 or 2 d (1864 pg/ml) and at 5 or 6 d (1910 pg/ml) after birth in very-low birthweight (VLBW) infants, but the levels at 14 d (3310 pg/ml) after birth were significantly higher than either of those levels. Plasma glicentin concentrations after feeding were significantly higher than those before feeding at 1 or 2 d and at 5 or 6 d after birth in NBW and LBW infants, but a significant increase in the plasma glicentin level after feeding was first observed at 14 d after birth in VLBW infants. There were no significant differences in the basal plasma (2401 and 2718 pg/ml) and postprandial (3007 and 3912 pg/ml) glicentin levels between breastfed and formula-fed infants.

Conclusion: The results of the study suggest that glicentin may play an important role in intestinal mucosal growth in the early period of life, although its role in VLBW infants should be further investigated.     

Characteristics of arterial stiffness in very low birth weight premature infants

Premature birth is a factor of increased blood pressure in adulthood. Little is known about the physiologic characteristics of the arterial bed in neonates. The aim of this study was to characterize in vivo the arterial compliance in neonates and its maturation profile in very low birth weight (VLBW) premature infants. A group of stable, VLBW premature infants was compared with a control group of near term neonates. The abdominal aortic wall distensibility coefficient (DC) and whole-body arterial compliance (WBAC) were determined using specifically designed noninvasive methods, based on ultrasonic measurements in combination with synchronous, beat-to-beat recording of aortic pulse pressure (PP). On the fifth day of life, WBAC and the CD were lower in VLBW premature infants than in controls. Furthermore, WBAC and the DC remained unchanged in VLBW premature infants 7 wk after birth. In conclusion, VLBW premature infants are characterized as early as the fifth day of life by high arterial stiffness, which persists when they reach their theoretical term. It can be speculated that early alteration of arterial elastic properties may pave the way for long-term elevation of arterial pressure in VLBW premature infants.     

Postnatal adaptation of cerebral blood flow using near infrared spectroscopy in extremely preterm infants undergoing high-frequency oscillatory ventilation

Aim: To determine cerebral blood flow using near infrared spectroscopy in extremely preterm infants undergoing high-frequency oscillatory ventilation during the first three days of life. Low cerebral blood flow has been associated with both intra-ventricular haemorrhage and periventricu-lar leucomalacia. It is well established that cerebral blood flow increases over the first three days of life in extremely preterm infants who are conventionally ventilated with intermittent positive pressure ventilation. However, there is no information about cerebral blood flow in preterm babies undergoing high-frequency oscillatory ventilation. In addition, there are concerns that high-frequency oscillatory ventilation may be associated with an increased incidence of intra-ventricular haemorrhage in premature infants. Methods: Thirteen appropriately grown, preterm infants of less than 28 wk gestation who were admitted to the neonatal unit at University College Hospital, London were studied using near infrared spectroscopy. Left ventricular output and right ventricular output were assessed echocardiographically. Results: Extremely preterm infants undergoing high-frequency oscillatory ventilation have remarkably low cerebral blood flow in the first 12 h of life, median 6.7 (range 4.4-11) mls. 100 g[Formula: See Text] min[Formula: See Text] followed by an increase over the subsequent three days. Left ventricular output also increased over the first three days of life, whereas right ventricular output showed no clear relationship with time. Despite low cerebral blood flow only one infant had evidence of major cerebral injury.

Conclusion: Cerebral blood flow is extremely low in this group of preterm babies. Despite this extremely low cerebral blood flow, the clinical outcome is good. There was an increase in cerebral blood flow and a corresponding increase in left ventricular output over the first few days of life.     

Pulmonary toxicity of monocrotaline differs at critical periods of lung development

We injected 3-day-old (neonatal), 8-day-old (infant), and 8-wk-old (adult) Sprague-Dawley rats with monocrotaline to examine the effect of a toxic agent at various stages of lung development. Two and four weeks after injection the rats were killed and the heart and lungs removed: the right and left ventricles were separated and weighed, the pulmonary artery was injected with barium-gelatin, and the lung was fixed in the inflated state. Morphometric techniques were applied to assess lung volume, alveolar size and number, and arterial size, muscularity, and concentration relative to alveolar. Rats injected with monocrotaline in the neonatal period did not survive to 3 wk. After 2 wk, there was no significant right ventricular hypertrophy and pulmonary vascular changes were no worse than in the other rat groups injected with monocrotaline, but alveolar development was severely impaired; less than one-third the normal number was present. Rats injected with monocrotaline in infancy had normal alveolar development. After 2-wk, the arterial changes, i.e. extension of muscle into peripheral arteries, medial hypertrophy of muscular arteries, and decreased arterial concentration relative to alveolar were similar to those observed in adult rats. After 4 wk, there was a decrease in medial hypertrophy associated with growth in artery size and only a lack of regression of right ventricular weight. In adult rats, after 4 wk medial hypertrophy became progressively more severe, the arterial concentration relative to alveolar decreased further, and right ventricular hypertrophy developed.(ABSTRACT TRUNCATED AT 250 WORDS)     

Left ventricular contractility in extremely premature infants in the first day and response to inotropes

The aim was to assess myocardial contractility in infants born <30 wk gestation developing low systemic blood flow (SBF) in the first day, and the effect of dobutamine versus dopamine. Superior vena cava (SVC) flow was used as a measure of SBF at 3, 10, and 24 h (n = 106). Infants with low SVC flow randomized to dopamine or dobutamine. Myocardial contractility was determined by the relationship between left ventricular (LV) mean velocity of circumferential fiber shortening (mVcfs) and wall stress. Infants who developed low SVC flow had significantly worse myocardial contractility at 3 h, but not 10 h. At 24 h, low-flow infants had lower than expected mVcfs for any given LV stress. In 37 infants randomized to inotrope, there was no significant difference in contractility at 10 microg/kg/min. At 20 microg/kg/min (n = 21), dopamine increased whereas dobutamine decreased LV stress. Infants on dobutamine had significantly lower than expected mVcfs for any given LV stress compared with infants on dopamine. Contractility was not improved by either inotrope at either dose. In conclusion, infants developing low SVC flow in the first day have worse myocardial contractility at 3 h. Neither inotrope increased contractility, but dopamine increased LV stress at 20 microg/kg/min.     

Morbidity in children born to women infected with human immunodeficiency virus in South Africa: does mode of feeding matter?

Aim: To examine infant morbidity risks associated with refraining from breastfeeding where it is used in an attempt to prevent mother-to-child transmission (MTCT) of human immunodeficiency virus (HIV). Methods: The population consisted of infants born to HIV-infected women in South Africa who were participating in a vitamin A intervention trial to prevent MTCT of HIV. Women chose to breastfeed or formula feed their infants according to UNAIDS guidelines. Actual feeding practices and morbidity were recorded at clinic follow-up visits at 1 wk, 6 wk, 3 mo and every 3 mo thereafter until 15 mo of age or cessation of breastfeeding. The infant's HIV status was assessed according to a predetermined algorithm. Results: HIV-infected infants who were never breastfed had a poorer outcome than those who were breastfed; 9 (60%) of those who were never breastfed had 3 or more morbidity episodes compared with 15 (32%) of breastfed children [odds ratio (OR) 4.05, 95% confidence interval (95% CI) 0.91-20.63, p = 0.05]. During the first 2 mo of life, never-breastfed infants (regardless of HIV status) were nearly twice as likely to have had an illness episode than breastfed infants (OR 1.91, 95% CI 1.17-3.13, p = 0.006).

Conclusion: The significant extra morbidity experienced in the first few months by all never-breastfed infants and at all times by HIV-infected infants who are not breastfed needs to be considered in all decisions by mothers, health workers and policy makers so as not to offset any gains achieved by decreasing HIV transmission through avoiding breastfeeding.     

生后早期床旁心脏超声预测极低出生体重儿动脉导管持续开放的研究(英文翻译)

目的 探讨出生早期床旁心脏超声预测极低出生体重儿（very low birth weight infant,VLBWI）动脉导管持续开放的价值。 方法 回顾性选取2020年3月至2021年6月收治的51例VLBWI为研究对象,入院时日龄≤3 d并且住院时间≥14 d。根据出生14 d及28 d动脉导管未闭（patent ductus arteriosus,PDA）直径大小分为3组：大PDA组（PDA直径≥2 mm）、小PDA组（PDA直径<2 mm）和PDA关闭组（PDA直径=0 mm）,比较3组间生后72 h的心脏超声参数。采用受试者工作特征（receiver operating characteristic,ROC）曲线评估生后72 h心脏超声参数预测生后14 d和28 d动脉导管持续开放（PDA直径≥2 mm）的价值。 结果 生后14 d时,大PDA组有17例,小PDA组11例,PDA关闭组23例;生后28 d时,大PDA组有14例,小PDA组9例,PDA关闭组26例。3组患儿间胎龄、出生体重、肺泡表面活性物质应用及低血压发生率的比较差异有统计学意义（P<0.05）。生后72 h的PDA直径、左肺动脉舒张末期流速、左心室输出量、左心室输出量/上腔静脉血流与生后14 d及28 d时动脉导管持续开放有关（P<0.05）;左心房/主动脉根部直径与生后28 d时动脉导管持续开放有关（P<0.05）。ROC曲线结果显示,生后72 h PDA直径预测生后14 d及28 d动脉导管持续开放的曲线下面积最大,分别为0.841和0.927;其次是左肺动脉舒张末期流速,其曲线下面积分别为0.793和0.833。 结论 生后72 h的床旁心脏超声指标,尤其是PDA直径及左肺动脉舒张末期流速,可预测VLBWI生后14 d和28 d动脉导管持续开放,为后续PDA早期目标性治疗策略的实施提供依据。     

Dopamine versus dobutamine in very low birthweight infants: endocrine effects

OBJECTIVES: To compare the endocrine effects of dopamine and dobutamine in hypotensive very low birthweight (VLBW) infants. DESIGN: Non-blinded randomised prospective trial. SETTING: Level III neonatal intensive care unit. PATIENTS: 35 hypotensive VLBW infants who did not respond to volume loading, assigned to receive dopamine or dobutamine. Measurements: Haemodynamic variables and serum levels of thyroid stimulating hormone (TSH), total thyroxine (T(4)), prolactin (PRL) and growth hormone were assessed during the first 72 h of treatment and the first 72 h after stopping treatment. RESULTS: Demographic and clinical data did not significantly differ between the two groups. Necessary cumulative and mean drug doses and maximum infusion required to normalise blood pressure were significantly higher in the dobutamine than in the dopamine group (p<0.01). Suppression of TSH, T(4) and PRL was observed in dopamine-treated newborns from 12 h of treatment onwards, whereas levels of growth hormone reduced significantly only at 12 h and 36 h of treatment (p<0.01). TSH, T(4) and PRL rebound was observed from the first day onwards after stopping dopamine. Dobutamine administration did not alter the profile of any of the hormones and no rebound was observed after stopping treatment. CONCLUSION: Dopamine and dobutamine both increase the systemic blood pressure, though dopamine is more effective. Dopamine reduces serum levels of TSH, T(4) and PRL in VLBW infants but such suppression is quickly reversed after treatment is stopped. Further research is required to assess if short-term iatrogenic pituitary suppression has longer-term consequences.     

Serial Pulsed Doppler Assessment of Early Left Ventricular Output in Critically Ill Very Low-Birth-Weight Infants

Serial, detailed assessments of left ventricular output (LVO) in critically ill very low-birth-weight (VLBW) infants of four different gestational ages were performed in the early neonatal period using pulsed Doppler echocardiography. Initially, the LVO values of all groups at 3 hours of age were relatively high. However, LVO dropped transiently at 12 hours and then increased again after 24 hours reaching a steady level of 160–180 ml/kg/min after 48 hours of age. In all four groups, heart rate also decreased significantly at 12 hours of age but did not increase at 24 hours of age. Both the left ventricular stroke volume and the left ventricular ejection fraction in all groups exhibited similar longitudinal changes to those observed for LVO. The LVO values observed in the lower gestational age group were significantly lower than those observed in the upper gestational group before 24 hours of age. Both patent ductus arteriosus and mechanical ventilation did not significantly influence the changes in LVO of VLBW infants at least before 36 hours of age. Our results suggest that in the early neonatal period, there are drastic changes in LVO of VLBW infants that reflect not only changes in heart rate but also changes in myocardial contractility.     

Rapid increase of blood pressure in extremely low birth weight infants after a single dose of dexamethasone

Blood pressure was retrospectively studied in all 22 extremely low birth weight infants (ELBW) (birth weight median 720 g, range 450–1020 g) who were admitted between July 1989 and October 1991 and received dexamethasone on days 2–25 (median 10) because of bronchopulmonary dysplasia or since lung function had not improved after installation of bovine surfactant. The average blood pressure during the 4 h before dexamethasone increased significantly (median individual increase 8 mmHg,P=0.0005) until 8–12 h thereafter. In addition to the lung disease, ten infants showed severe arterial hypotension with prolonged capillary refilling time (>3s) and oliguria and needed continuous infusion of epinephrine to increase blood pressure and urinary flow after treatment with colloids, dopamine and dobutamine had proved ineffective. Epinephrine infusion could be stopped in eight infants 8h after dexamethasone administration. In ELBW infants blood pressure rose 8–12 h after a single dose of 0.25 mg/kg dexamethasone. In ELBW infants suffering from arterial hypotension who do not respond to infusion of colloids and catecholamines, dexamethasone may represent a new therapeutic tool.     

Coagulase-negative staphylococcal infections in a neonatal intensive care unit: In vivo response to cloxacillin

BACKGROUND

Following the introduction of cloxacillin and gentamicin as the first line of treatment for possible late-onset sepsis (LOS) in the authors’ neonatal intensive care unit (NICU), it was subsequently noted that very low birth weight (VLBW) infants improved clinically, despite subsequently positive blood cultures for oxacillin-resistant, coagulase-negative Staphylococcus (CONS). The results of the management of VLBW infants with CONS sepsis during one calendar year, based on clinical rather than laboratory findings, are presented.

METHODS

VLBW infants with LOS were identified through the neonatal database, and the charts of those with CONS were reviewed for antibiotic usage, antibiotic resistance pattern, clearance of CONS from the blood and NICU discharge status. Oxacillin sensitivity was determined by the presence of the mecA gene.

RESULTS

From January 1 to December 31, 2002, 27 VLBW infants, treated in the authors’ NICU for LOS due to CONS, were identified. The mean age of LOS infants with CONS was 15 days (median 12 days; range three to 54 days), the mean birth weight (± SD) was 904±247 g, and the mean gestational age at birth (± SD) was 27±2 weeks. All infants were started on cloxacillin and gentamicin, and improved clinically over the first 48 h. Six isolates were sensitive to cloxacillin. Twenty-three infants grew oxacillin-resistant CONS, eight of whom had persistence of CONS on repeat culture secondary to central lines. Two infants grew two strains of CONS. Eighteen of 22 infants (82%) with in vitro oxacillin-resistant CONS had clearance of bacteremia with cloxacillin and gentamicin. Ten infants (37%) received vancomycin, based on the authors’ guidelines. There were no cases of prolonged bacteremia requiring rifampicin. Three infants died, but none of the deaths could be attributed to CONS.

DISCUSSION

The authors describe clinical improvement with clearance of CONS using cloxacillin and gentamicin, despite laboratory results suggesting oxacillin resistance. The authors’ unit policy was based on clinical response and permitted the continuation of cloxacillin, provided that a repeat blood culture was negative. Vancomycin use was suggested for clinical deterioration or persistence of CONS. These results question the in vitro tests of resistance. Clearance of oxacillin-resistant CONS from the blood points to in vivo sensitivity, while the laboratory testing suggests in vitro resistance. The absence of subsequent positive blood cultures for CONS confirms clearance of this organism.

CONCLUSION

It was demonstrated that cloxacillin (150 mg/kg/day dose), along with gentamicin, can clear CONS from the blood within 48 h. The relationship between in vivo and in vitro sensitivities also needs to be further studied both in the laboratory and in a prospective trial.     

Postnatal Left Ventricular Contractility in Very Low Birth Weight Infants

The objective of the study was to evaluate postnatal changes in left ventricular (LV) contractility in very low birth weight (VLBW) infants. An echocardiographic study comparing 18 VLBW infants without significant complications and 16 normal term infants was carried out at the Neonatal Intensive Care Unit in Akita University Medical Hospital, Japan. The echocardiographic examinations were performed within 6 hours of birth and on day 5. We obtained the relations between rate-corrected mean velocity of circumferential fiber shortening (mVcfc) and end-systolic wall stress (ESS), which were calculated from two-dimensional LV short-axis views to compensate for the distorted LV shape, and we compared these relations statistically. In both VLBW and term infants there were inverse linear correlations between mVcfc and ESS for each study period (p < 0.05). The regression line of VLBW infants had a lower y-intercept and a steeper slope than that of term infants at 6 hours of age but almost corresponded on day 5. It is concluded that the left ventricle of VLBW infants adapts to postnatal hemodynamic alterations with low contractility but operates with a contractile state similar to that of term infants on day 5.     

Changes in serum leptin concentration after corticosteroid treatment in preterm infants

The aim of this study was to investigate the effect of postnatal systemic dexamethasone on serum leptin, insulin and hormones of the hypothalamic-pituitary-adrenal (HPA) axis in preterm, very low birthweight (VLBW) infants. Nineteen VLBW infants who received a 3 wk dose tapering course of dexamethasone for treatment of bronchopulmonary dysplasia were prospectively enrolled. Blood for hormone assays was collected immediately before the start of the dexamethasone course (T(d-per)), 3 wk after commencement of the drug (T(d-end)) and 2 wk after dexamethasone treatment had been stopped (T(d-post)). In addition, 28 VLBW infants who participated in a concurrent longitudinal leptin study within the same period but did not receive corticosteroid had their serum leptin and insulin concentrations serially monitored. Blood specimens for the latter group of infants were obtained at 2 (T(wk-2)), 5 (T(wk-5)) and 7 (T(wk-7)) wk of postnatal age. Serum leptin and insulin at T(d-end) were significantly increased, whereas plasma ACTH and serum cortisol were significantly suppressed compared with the pretreatment (T(d-pre)) levels in the corticosteroid group (p < 0.0001 for leptin and insulin; p < 0.05 and p < 0.001 for ACTH and cortisol, respectively). In contrast, serum leptin and insulin at weeks 5 (T(wk-5)) and 7 (T(wk-7)) did not differ significantly from their respective levels at week 2 (T(wk-2)) in the non-treatment group. CONCLUSION: The administration of systemic corticosteroid resulted in significant increases in serum leptin and insulin, but marked suppression of hormones of the HPA axis. The effect of dexamethasone on the "adipoinsular" and HPA axes was transient and reversible. The adipoinsular axis in preterm infants is likely to be functional and active at an early stage of human development, and leptin may regulate energy balance in VLBW infants in the early postnatal period. Corticosteroids may, through the adipoinsular axis or its associated pathways, mediate in the regulation of body weight in preterm neonates.     

Early cessation of breast milk feeding in very low birthweight infants

This investigation was carried out to comparatively assess the duration of breast milk feeding and to analyze risk factors for early cessation of breast milk feeding in term and very preterm infants. A cohort study was performed in 89 consecutive very low birthweight (VLBW) infants (<1500 g) who survived for at least for one week, and 177 term infants with birthweights >2500 g born in the same hospital matched for gender and multiplicity. Median duration of breast milk feeding, as determined from charts and questionnaires mailed to the mothers at 6 and 12 months corrected age, was 36 days in VLBW infants, compared to 112 days in control infants (P<0.0001). In both VLBW and control infants, smoking during pregnancy, low maternal and low paternal school education were each significantly associated with short duration of breast milk feeding. In VLBW infants, multiple pregnancy and gestational age <29 weeks were each associated with prolonged breast milk feeding, as were maternal age >35 years and spontaneous pregnancy (as opposed to pregnancy following infertility treatment) in term infants. Multivariate analysis revealed that VLBW, smoking and low parental school education were independent negative predictors of breast milk feeding. While these results emphasize the need for special support of VLBW infant mothers promoting lactation, the relationships between smoking, school education and breast milk feeding in both strata show that efforts to increase breast milk feeding require a public health perspective.     

Late-onset neutropenia in very low birthweight infants

Aim : To evaluate the incidence and duration of late-onset neutropenia (defined as an absolute neutrophil count (ANC) <1500 mm⁻³ at a postnatal age of >3 wk) in a population of infants with birthweight <2000 g, and to determine whether copper deficiency, a possible cause of both anemia and neutropenia, may be associated with this complication. Methods : Complete blood cell count and differential were assessed in 247 low (LBW) and very low birthweight (VLBW) infants who were discharged after 3 wk of life. In neutropenic infants plasma copper and ceruloplasmin levels were also measured. Results : Late-onset neutropenia was detected in 11 out of 147 VLBW infants (7.5%) and in 7 out of 127 LBW infants (5.5%). A neutrophil count of <1000 mm⁻³ was observed in 14 infants (5.1%). A significantly lower gestational age was found in neutropenic infants compared with non-neutropenic infants. In neutropenic infants ANCs were significantly correlated with hemoglobin and hematocrit. In addition, a significant negative correlation was found between neutrophil and reticulocyte counts. Plasma copper concentration was significantly correlated with birthweight. Oral copper sulfate was administered to infants with plasma copper concentration <50 μg dl⁻¹, and did not seem to affect ANC, hemoglobin, hematocrit or reticulocyte counts.
Conclusion : Late-onset neutropenia appears to be a benign condition that is not associated with any particular complication and does not require specific treatment. Reference ranges after the early neonatal period and during the first few months of life in LBW and VLBW infants should probably be set at lower values.     

Late-onset neutropenia in very low birthweight infants

AIM: To evaluate the incidence and duration of late-onset neutropenia (defined as an absolute neutrophil count (ANC) <1500 mm(-3) at a postnatal age of >3 wk) in a population of infants with birthweight <2000 g, and to determine whether copper deficiency, a possible cause of both anemia and neutropenia, may be associated with this complication. METHODS: Complete blood cell count and differential were assessed in 247 low (LBW) and very low birthweight (VLBW) infants who were discharged after 3 wk of life. In neutropenic infants plasma copper and ceruloplasmin levels were also measured. RESULTS: Late-onset neutropenia was detected in 11 out of 147 VLBW infants (7.5%) and in 7 out of 127 LBW infants (5.5%). A neutrophil count of <1000 mm(-3) was observed in 14 infants (5.1%). A significantly lower gestational age was found in neutropenic infants compared with non-neutropenic infants. In neutropenic infants ANCs were significantly correlated with hemoglobin and hematocrit. In addition, a significant negative correlation was found between neutrophil and reticulocyte counts. Plasma copper concentration was significantly correlated with birthweight. Oral copper sulfate was administered to infants with plasma copper concentration <50 microg dl(-1), and did not seem to affect ANC, hemoglobin, hematocrit or reticulocyte counts. CONCLUSION: Late-onset neutropenia appears to be a benign condition that is not associated with any particular complication and does not require specific treatment. Reference ranges after the early neonatal period and during the first few months of life in LBW and VLBW infants should probably be set at lower values.     

Left and Right Ventricular Myocardial Performance Index (Tei Index) in Very-Low-Birth-Weight Infants

This study presents a report of serial assessment of ventricular myocardial performance index (Tei index) in very-low-birth-weight (VLBW) infants. One hundred ninety-five VLBW infants, weighing <1,500 g, who were admitted to the neonatal intensive care units at Kakogawa Municipal Hospital between September 2000 and August 2004. Left ventricular (LV) and right ventricular (RV) Tei indexes were assessed consecutively from birth to day 28 in all VLBW infants using pulsed-Doppler echocardiography. The mean values of the LV Tei index rose rapidly from 3 to 12 h after birth and then fell significantly after 24 h. Those of the RV Tei index increased slightly from 3 to 12 h, then decreased drastically after 24 h. The LV Tei index was found to correlate inversely with LV output and LV ejection fraction in the early neonatal period, while the relationship between the LV Tei index and the LV E/A velocity ratio was not significant. The RV Tei index was inversely correlated with RV output. In conclusion, both of the ventricular Tei indexes in VLBW infants showed drastic and significant changes on the first to second day after birth.