Restrictive guideline reduces platelet count thresholds for transfusions in very low birth weight preterm infants

Background and Objectives Platelet transfusions are performed almost entirely according to expert experience. This study assessed the effectiveness of a restrictive guideline to reduce platelet transfusions in preterm infants. Methods A retrospective cohort of preterm infants with a birth weight of <1500 g had been born in 2 periods. In Period 1, a transfusion was indicated for a platelet count of <50 000/ml in clinically stable neonates or <100 000/ml in bleeding or clinically unstable infants. In Period 2, the indications were restricted to <25 000/ml in clinically stable neonates, or <50 000/ml in newborns who were either on mechanical ventilation, subject to imminent invasive procedures, within 72 h following a seizure, or extremely premature and <7 days old. A count of <100 000/ml was indicated for bleeding or major surgery. Results Periods 1 and 2 comprised 121 and 134 neonates, respectively. The rates of ventricular haemorrhage and intrahospital death were similar in both periods. The percentage of transfused infants, the odds of receiving a platelet transfusion, the mean platelet count before transfusion and the percentage of transfusions with a platelet count >50,000/ml were greater in Period 1. Among thrombocytopenic neonates, the percentage of transfused neonates and the number of transfusions were similar in both groups. Conclusion The restrictive guideline for platelet transfusions reduced the platelet count thresholds for neonatal transfusions without increasing the rate of ventricular haemorrhage.     

Humoral immune response to measles and varicella vaccination in former very low birth weight preterm infants

Introduction

Immune response to vaccination in infants born prematurely may be lower than in infants born at full-term. Some clinical factors might be associated with humoral immune response.

极低出生体重儿45例的临床分析

目的研究极低出生体重儿的临床情况和并发症的防治措施。方法对2008-01～2010-10在新生儿科住院的45例极低出生体重儿(含3例超低出生体重儿)的临床资料进行回顾性分析。结果 45例极低出生体重儿中并发症发生率为100%,共发生并发症175例次,平均3.89例次,排在前5位的依次为低蛋白血症28例(62.22%)、高胆红素血症25例(55.55%)、低血糖症24例(53.33%)、贫血23例(51.11%)、肺透明膜病14例(31.11%)。发生2种以上并发症的43例,占95.55%,发生1、2、3、4、5、6、7、8种并发症的分别为4.44%、24.44%、13.33%、20.00%、20.00%、11.11%、4.44%、2.22%;45例极低出生体重儿中存活34例,存活率为75.56%,死亡2例,放弃治疗9例(于放弃后1～2 d内死亡),病死率为24.44%,在死亡的11例中发生肺透明膜病9例,占81.82%。结论极低出生体重儿生活能力低下,并发症多,病死率较高,其病死原因主要是肺透明膜病,预防肺透明膜病可望降低极低出生体重儿的病死率。     

Adrenocorticotropin and corticotropin-releasing hormone tests in preterm infants

The short ACTH test is used in evaluating the hypothalamo-pituitary-adrenal axis (HPA-axis) in preterm neonates after dexamethasone treatment. This test mainly examines primary adrenal suppression but is also used as a method to test secondary adrenal insufficiency because long-term deprivation of ACTH causes atrophy of the adrenal cortex. The CRH test, on the other hand, directly examines the function of the pituitary. We tested 18 infants in the neonatal intensive care unit with both the ACTH test and the CRH test to determine which of these two tests more reliably demonstrates HPA-axis suppression. One patient had normal responses both in the ACTH test and in the CRH test when the limit of 360 nmol/L was used as a sign of proper cortisol secretion. In four cases the patients' cortisol secretion would have been regarded as normal by the low-dose ACTH test, whereas the CRH test did not show an adequate cortisol response. In conclusion, the ACTH test did not reliably indicate HPA-axis suppression after a short (<2 weeks) course of dexamethasone therapy in this study. Therefore, whether the infant is or will be under acute stress after short glucocorticoid treatment, ensuring adequate cortisol secretion with the CRH test should be considered.     

极低出生体重儿hsPDA的血流动力学变化

极低出生体重儿在出生后1周内动脉导管未闭(patent ductus arteriosus,PDA)或重新开放的发生率高,形成持续性动脉导管(ductusarteriosus,DA)开放,造成血流动力学改变,持续性DA常常需要内科或手术治疗[1].……     

Early childhood neurodevelopment in very low birth weight infants with predischarge apnea

Apnea commonly occurs in preterm infants and may persist beyond term. We prospectively investigated the relationship between apnea that persisted beyond 35 weeks post-conceptional age and subsequent neurodevelopment in early childhood. Between January, 1990-November, 1993, we performed predischarge respiratory recordings, using 24-hr, 4-channel pneumography, at 35 weeks or more of postconceptional age in 164 infants (birth weight, <1,250 g; gestational age, < or = 32 weeks), who subsequently underwent multidisciplinary neurodevelopmental assessment at 15-64 (median 24) months of adjusted age. The duration of initial artificial ventilation for respiratory distress syndrome and the grade of intraventricular hemorrhage were independent predictors of neurodevelopmental outcome. Mean oximetry desaturation and frequency of predischarge apnea correlated with mental and motor developmental scores. Mean oximetry desaturation during apnea was an independent predictor for motor score in the total population, and for both mental and motor scores in 50 infants with grade 3 or 4 intraventricular hemorrhage, but not in 114 infants without grade 3 or 4 intraventricular hemorrhage. Despite its limited predictability for early childhood neurodevelopment, predischarge respiratory recordings may be useful in predicting subsequent neurodevelopment of high-risk preterm infants, especially those with severe intraventricular hemorrhage.     

Severity of bronchopulmonary dysplasia and increased risk of feeding desaturation and growth delay in very low birth weight preterm infants

Oral feeding has been reported to compromise breathing among preterm infants with bronchopulmonary dysplasia (BPD) during hospitalization or shortly after discharge. However, limited information was available concerning whether preterm infants with BPD remain vulnerable to feeding and growth insufficiency after a longer term of follow‐up. The purpose of this study was therefore to examine the effect of severity of BPD on pulse oxygen saturation (SpO₂) during feeding and growth in very low birth weight (VLBW) preterm infants during infancy. Seventy‐two preterm infants with VLBW and 15 term infants were prospectively examined their growth and SpO₂ during feeding at 2, 4, and 6 months of corrected age. The severity of BPD was graded in VLBW infants according to the American National Institutes of Health consensus definition. In comparison to VLBW infants with mild BPD and term infants, VLBW infants with severe BPD showed significantly lower mean levels of SpO₂ during feeding at 2–6 months corrected age (P < 0.05). Those with severe BPD further exhibited higher rates of growth delay (weight < 10th percentile) throughout the study period. Among VLBW infants, severe BPD had an adverse relation with subsequent weight measures after adjustment for medical and demographic confounding variables (β = ?904 g, P = 0.03). The consensus BPD definition is useful to identify those preterm infants who are at greater risk of feeding desaturation and growth delay during infancy and close monitoring of SpO₂ during feeding should be advised. Pediatr Pulmonol. 2010; 45:165–173. © 2010 Wiley‐Liss, Inc.     

Impaired adrenocortical function in very low birth weight infants after multiple pregnancies

OBJECTIVE: To evaluate the differences in adrenal function between very low birth weight (VLBW) infants from singleton and multiple pregnancies. DESIGN AND METHODS: Forty infants of birth weights less than 1500 g underwent an ACTH test. Thirty infants born from singleton pregnancies (singleton group) and ten born from multiple pregnancies (multiple group) were enrolled. A baseline blood sample was drawn for cortisol measurement and thereafter serum cortisol was measured 1 and 2 h after an i.v. injection of ACTH. RESULTS: In multiple pregnancies, the median basal cortisol level of the infants was significantly lower than that in the singletons. The median cortisol level at 1 and 2 h after administration of ACTH was significantly lower in infants from multiple gestations than in singletons. Of infants from the multiple gestation group six, and of the singleton infants 12, had baseline cortisol levels lower than the reference values (P=0.48). One hour after ACTH stimulation all multiple and 53% of the singleton group infants showed a subnormal (<500 nmol/l, P=0.007) cortisol response. Two hours after ACTH, nine multiple group patients and 43% of the singletons had subnormal (<500 nmol/l, P=0.01) stimulated cortisol levels. CONCLUSIONS: We have concluded that VLBW infants from multiple gestations seem to be at an increased risk of insufficient postnatal adrenocortical function. In the future, specific attention should be paid to evaluate further newborn infants from multiple pregnancies with regard to a possible benefit of hydrocortisone substitution in stressful clinical situations.     

The effects of racemic albuterol versus levalbuterol in very low birth weight infants

Bronchodilators have been used in premature infants. Levalbuterol (LEV) an R‐isomer of Albuterol has fewer hemodynamic side effects than Racemic Albuterol (RAC) in adults and children. In a retrospective study we sought to investigate the effects of LEV (0.31 mg) versus RAC (1.25 mg) in very low‐birth weight infants (VLBW) who were treated with a beta‐2 agonist for ≥2 weeks. Medical records (between January 2001 and December 2006) were reviewed for patients' demographics, medications use, hemodynamic and respiratory parameters, hypokalemia and hyperglycemia. Among 811 VLBW infants who were admitted to our NICU, 16 infants received RAC and 31 infants received LEV for ≥2 weeks. Infants who received RAC were younger, smaller, and received less Ipratropium Bromide (IB) than infants who received LEV [26.1 ± 1.2 weeks vs. 28.1 ± 3.7 weeks (P = 0.01), 817 ± 211 g vs. 1,127 ± 589 g (P = 0.01) and 2/16 (12%) vs. 15/31 (48%; P = 0.01); respectively]. In infants treated exclusively with RAC or LEV without IB, mean arterial blood pressures were lower in the RAC (n = 14) than the LEV group (n = 16, P = 0.05 by general linear model with repeated measures); however there were no differences in daily heart rates, oxygen supplementations, oxygen saturations, or respiratory rates. Also there were no differences between the two groups in hypokalemia or hyperglycemia. We conclude that LEV at a dose of 0.31 mg might have an indication in VLBW infants who are at risk for hemodynamic instability. Pediatr Pulmonol. 2009; 44:778–783. © 2009 Wiley‐Liss, Inc.     

极低体重早产儿动脉导管未闭的床旁外科治疗

目的 探讨极极低体重早产儿动脉导管未闭（PDA）床旁外科治疗的临床效果.方法 纳入24例诊断PDA的极低体重早产儿,行床旁开胸PDA结扎术,从术前准备、麻醉管理及手术方法三个方面分析极低体重早产儿床旁PDA手术的特点及临床疗效.结果 24例极低体重早产儿床旁手术均取得成功,平均手术时间为（30.8±12.5） min,出血量平均为（10.5±4.6）ml,呼吸机辅助平均时间为（6.4±2.5）d.术后平均动脉压均有不同程度升高,脉压增大.所有患儿术后顺利拔除气管插管,围术期无意外及明显并发症发生.术后6个月所有患儿均无动脉导管再通和肺炎发作.结论 对于极低体重早产儿,实施床旁PDA手术安全可行.     

Reference ranges for cardiac dimensions and blood flow velocity in preterm infants

Aim—To establish reference ranges for cardiac dimensions and Doppler measurements in preterm infants.
Methods—79 infants of less than 34 weeks' gestation were examined by echocardiography on days 0, 7, and 28 after birth, to produce a set of reference ranges and to examine changes in these indices over the first month of life. The following dimensions were measured: interventricular septum, left ventricular posterior wall, left interventricular diameter at end systole and diastole, left atrium, and aortic root; Doppler measurements were made of maximum blood flow velocity (Vmax) through the pulmonary, aortic, mitral, and tricuspid valves.
Results—Reference ranges are given. Cardiac dimensions correlated well with gestation and birth weight but Vmax did not. There was a significant increase in measurements over time. The "normal" preterm infant also appeared to often have asymmetrical septal hypertrophy. Antenatal dexamethasone administration did not appear to affect the measurements.
Conclusions—There is a close correlation with both gestation and birth weight for all physical measurements. Echocardiograms in preterm babies clearly differ from those in older children and adults.

Keywords: cardiac dimensions;  blood flow velocity;  preterm infant     

The corticotrophin-releasing hormone test in preterm infants

OBJECTIVE: The developing hypothalamic--pituitary--adrenal axis (HPAA) may be immature and not yet fully functional in preterm infants. This may result in an inappropriate adrenal response to stress. Little is known about the pituitary--adrenal response to corticotrophin-releasing hormone (CRH) stimulation during the early neonatal period in preterm infants born before 32 weeks of gestation. Therefore, in a first study we investigated the pituitary--adrenal response to 1 microg/kg CRH i.v. in 13 preterm infants born less-than-or-equal 32 weeks of gestation. In addition, in a randomized placebo-controlled study we compared the pituitary--adrenal response of 1 microg/kg CRH to placebo and stimulation with 2 microg/kg CRH. RESULTS: In the first study, the level of ACTH increased from 6.9 +/-2.1 to 11.6 +/- 5.1 pmol/l (P < 0.01) and cortisol increased from 350 plus minus 115 to 582 +/- 201 nmol/l (P < 0.05). Thirty-eight percent of the studied infants showed a maximal level of ACTH < 9 pmol/l, and 15% showed a maximal level of cortisol < 360 nmol/l. In the randomized study, infants in the 1 microg/kg and in the 2 microg/kg CRH group, but not in the placebo group, showed a significant increase in cortisol and ACTH after stimulation (P < 0.01). Stimulated levels of ACTH and cortisol were significantly higher in the 2 microg/kg group compared with the placebo and the 1 microg/kg group. No differences were found for plasma ACTH and cortisol levels in the 1 microg/kg group compared with the placebo group. Basal levels of cortisol and ACTH obtained from the first and from the randomized study correlated significantly (n = 29; r = 0.42, P < 0.03). In addition, in infants stimulated with 1 microg/kg CRH a lower cortisol response correlated with a longer stay in hospital (n = 13; r = --0.57, P < 0.05). CONCLUSIONS: In this study we show that a 1 microg/kg CRH stimulation test in preterm infants results more often in an inappropriate adrenal response while stimulation with 2 microg/kg CRH gives rise to an appropriate response in all studied infants. Furthermore, stimulation with 2 microg/kg CRH results in higher levels of ACTH and cortisol compared to placebo and 1 microg/kg CRH. We conclude that in preterm infants the ability of the pituitary to respond adequately to CRH stimulation depends on the dose of CRH used and may also be dependent on the maturity of the pituitary--adrenal axis.     

Immunoglobulin serum levels in very low birth weight infants treated with different intravenous preparations

Summary Parenteral human immunoglobulin (IVIG) administration is widely used in low birth weight (LBW) infants for prevention and therapy of neonatal infection. In previous studies, IVIG preparations containing IgG and low IgM concentrations were commonly used. In this study we compare immunoglobulin serum levels in two groups of healthy preterm infants receiving prophylactically standard IVIG (Sandoglobulin, 0.1 mg/kg IgM) or IgM-enriched IVIG (Pentaglobin, 30 mg/kg IgM). Immunoglobulin levels were assayed by rate nephelometry at birth and at 3, 5, 7, and 14 days after birth. The two groups of patients were matched for gestational age (31±2.3 weeks), birth weight (1320±340 g), and serum IgG (4.1±1.9 g/l) and IgM (0.22±0.18 g/l) levels at birth. Significantly higher IgM levels were observed at 3 and 5 days after IgM-enriched IVIG administration (p<0.01). Higher IgG levels were attained and persisted for 2 weeks after standard IVIG administration (p<0.01). These data indicate different IgG and IgM target levels in LBW infants treated with different immunoglobulin preparations.     

The prognosis of refractory hypotension and severe intraventricular hemorrhage in very low birth weight infants

Background:The increased survival rate among very low birth weight infants has resulted in a higher risk for developing neuro-complications such as intraventricular hemorrhage (IVH), periventricular leukomalacia (PVL), and adverse neurodevelopmental outcomes.Purpose:We examined refractory hypotension experienced within a week of life in association with severe IVH (grades 3–4) among very low birth weight infants (VLBWIs).Method:Between Jan 2014 and Dec 2017, the clinical data of 191 VLBWIs were retrospectively chart reviewed. Of a total of 191 VLBWIs, 71.2% (136/191) had IVH, and 28.7% (55/191) had severe IVH.Results:The VLBWI with severe IVH group (grade 3–4) presented with a significantly lower gestational age along with higher use of postnatal hydrocortisone for refractory hypotension within a week of life. Resuscitation at delivery, pulmonary hemorrhage, neonatal seizure, and PVL were significantly more frequent in the severe IVH group (P < .05). Higher mortality occurred in the VLBWI with severe IVH group (P < .001). The multivariable logistic regression analysis consistently showed that refractory hypotension within a week of life and neonatal seizures were significantly associated with severe IVH. Those in the severe IVH and refractory hypotension groups had significantly lower composite cognitive, language, motor scores in Bayley Scales of Infant and Toddler Development III scores at corrected 18–24 months.Conclusion:Refractory hypotension within a week of life and seizures were consistently associated with severe IVH and developmental delay at corrected 18–24 months. VLBWI who experienced refractory hypotension within a week of life may indicate a more vulnerable clinical setting with a higher risk for developmental delay.     

Predictors of survival in very low birth weight infants at the University Hospital of the West Indies, Jamaica

The use of prenatal steroids is an effective, simple clinical intervention that can be implemented in developing countries to help decrease mortality in very low birth weight infants.