Transient hyperinsulinism in asphyxiated newborn infants

Hypoglycemia in birth asphyxiated infants is attributed to glycogen depletion. We observed three term AGA (Appropriate for Gestational Age) infants with birth asphyxia, who developed hyperinsulinemic hypoglycemia postnatally. All had inappropriately high serum insulin concentrations for their blood glucose levels, and needed glucose infusion rates of greater than 8 mg/kg/min for several days to maintain normoglycemia. All infants recovered spontaneously.     

Hypothermia reduces neurological damage in asphyxiated newborn infants

BACKGROUND: Perinatal asphyxia remains one of the most devastating neurologic processes. There is experimental and clinical evidence that cerebral cooling may suppress the biochemical cascades leading to delayed cerebral damage. OBJECTIVE: To determine if hypothermia started soon after delivery reduces cerebral damage in term infants. DESIGN/METHODS: Retrospective chart analysis with historical controls. Ten asphyxiated newborns treated with hypothermia between October 1998 and October 1999 were compared to 11 asphyxiated newborns admitted from September 1997 to September 1998. Characteristics at birth of infants of the two groups (control and hypothermia) were comparable. After obtaining parental consent, whole-body hypothermia was induced before the 6th hour of life by placing a cold blanket (Polar Air, Augustine Medical Inc., model 600) around the body of the patients. Rectal temperature was maintained between 32 and 34 degrees C for 72 h. Outcome was assessed by neurological evaluation at birth and every 3 months up to the 12th month. Brain MRI was performed in the 2nd month. We had no evidence of severe adverse events related to hypothermia. In the hypothermic group there was a significant (p < 0.05) reduction of major neurologic abnormalities at follow-up and abnormal MRI findings. CONCLUSIONS: Hypothermia appears to be safe. Our results on morphological damage evaluated by brain MRI and neurological outcome are encouraging: randomized controlled trials are needed to confirm this experience.     

Cerebral blood-flow velocities in predicting outcome of asphyxiated newborn infants

AIM: To evaluate the role of early (up to 12 h) changes in cerebral blood-flow (CBF) velocity in predicting the severity of hypoxic-ischaemic encephalopathy (HIE) and long-term outcome in asphyxiated term infants. METHODS: CBF velocities were investigated by colour Doppler ultrasonography in 81 healthy and 60 asphyxiated term infants at least three times during the first 5 d of life. The psychomotor development of infants was followed up to 18 mo. RESULTS: No differences in CBF velocities were found at the age of 2-6 h between infants with severe and mild-moderate HIE, mean CBF velocity [mean (95% CI of mean CBF velocity)] in anterior cerebral artery [14.9 (1.4-28.4)cm/s] and [13.9 (11.1-16.7) cm/s], respectively, and between infants with poor outcome (death or severe disability) and with normal development/mild impairments. By the age of 12 h infants with mild-moderate HIE and infants with normal development/mild impairments had decreased CBF velocity in the anterior cerebral artery, and infants with severe HIE or poor outcome had increased mean CBF velocity in anterior, medial cerebral and basilar artery compared to the control group. CONCLUSION: The value of CBF velocity changes to predict poor outcome in asphyxiated infants is low 2-6 h after asphyxia, but increases by the age of 12 ho.     

Brain-specific proteins in the cerebrospinal fluid of severely asphyxiated newborn infants

Upcoming trials of neuroprotective strategies in severely asphyxiated newborn infants emphasize the need for early and objective markers of both good and bad long-term prognosis. Traditional markers such as neurological depression and seizures are not specific. Aim : To study whether measurement in the cerebrospinal fluid of some proteins known to be specific to the central nervous system was in covariance with the clinical course and long-term prognosis. Methods : Twenty-two asphyxiated infants were included in the study and compared with a control group of 8 infants without signs of perinatal asphyxia. Cerebrospinal fluid (CSF) was collected during the first 4 d of life and analysed for neurofilament protein (NFp), glial fibrillary acidic protein (GFAp), protein S-100 and neuron-specific enolase (NSE). Results : The concentrations of all four proteins were significantly increased in the CSF of asphyxiated infants. The concentrations correlated significantly with other indicators of long-term prognosis and to neurological impairment at 1 y of age, or death before that time. Specifically, concentrations were excessively high in the five infants who died.

Conclusions : High concentrations of brain-specific proteins are released into the CSF of asphyxiated infants. It might therefore be useful to measure these concentrations when excluding patients with the gravest prognosis from neuroprotective trials.     

Hemodynamic effects of dobutamine in children with cardiovascular failure

The effect of dobutamine, a synthetic catecholamine, was studied in 12 patients aged one day to 14 years with low cardiac output syndromes.After initial stabilization of the patients dobutamine was administered by continuous infusion in a dosage of 7.5 or 10 g/kg/min.Heart rate, cardiac output (using thermodilution technique and/or pulse contour method), mean systemic and mean pulmonary artery pressures were determined before and after the dobutamine infusion. Systemic and pulmonary vascular resistances, cardiac index and stroke volume index were calculated.Cardiac output and cardiac index increased significantly in every patient, whereas the heart rate changed only slightly, suggesting that the increase in cardiac output was mainly due to the alteration of stroke volume. The mean arterial pressure increased significantly, but the mean pulmonary artery pressure was unchanged. No side effects were observed during the dobutamine infusion. Dobutamine is a potent inotropic drug with limited chronotropic and peripheral vascular effects in newborns, infants and chidren.     

窒息新生儿血清总胆汁酸、前白蛋白变化及其临床意义探讨

目的探讨窒息时新生儿血清总胆汁酸(TBA)、前白蛋白(PAB)变化及其临床意义。方法检测各30例轻度、重度窒息新生儿及20例缺氧缺血性脑病(HIE)新生儿的(TBA)、(PAB)、丙氨酸转氨酶(ALT)、白蛋白(ALB)水平,并设30例正常新生儿为对照。结果轻度、重度窒息儿和HIE新生儿血清TBA、PAB水平与正常儿比较差异均有非常显著性(P<0.001)窒息时血清TBA、PAB水平与Apgar评分均呈线性相关(r=0.571,-0.689,P<0.001),随病情好转血清TBA和PAB水平逐渐恢复正常。结论血清TBA和PAB是反映窒息儿肝功能损害灵敏的生化指标,动态测定血清TBA和PAB水平变化能很好地、灵敏地反映窒息儿肝脏损害情况及病情转归。     

窒息新生儿血清总胆汁酸、前白蛋白变化及其临床意义探讨

目的探讨窒息时新生儿血清总胆汁酸(TBA)、前白蛋白(PAB)变化及其临床意义.方法检测各30例轻度、重度窒息新生儿及20例缺氧缺血性脑病(HIE)新生儿的(TBA)、(PAB)、丙氨酸转氨酶(ALT)、白蛋白(ALB)水平,并设30例正常新生儿为对照.结果轻度、重度窒息儿和HIE新生儿血清TBA、PAB水平与正常儿比较差异均有非常显著性(P＜0.001)窒息时血清TBA、PAB水平与Apgar评分均呈线性相关(r=0.571,-0.689,P＜0.001),随病情好转血清TBA和PAB水平逐渐恢复正常.结论血清TBA和PAB是反映窒息儿肝功能损害灵敏的生化指标,动态测定血清TBA和PAB水平变化能很好地、灵敏地反映窒息儿肝脏损害情况及病情转归.     

新生猪窒息模型的心肌损害的研究

目的　建立新生猪急性低氧性心肌损害模型。方法　 19只新生猪随机分成对照组(n =8)和窒息组 (n =11)。夹闭气管插管 10min建立新生猪窒息模型。窒息复苏后 6h测定血清中肌酸激酶心肌同工酶 (CK MB)和心肌钙蛋白T(cTnT)的含量 ;运用超声心动图检测各项心功能指标 ,包括左室射血分数 (LVEF)、右室射血分数 (RVEF)、二尖瓣及三尖瓣口舒张期血流EV/AV比值 (MVE/A ,TVE/A)、二尖瓣及三尖瓣环运动速度e/a比值 (MVe/a ,TVe/a)、左室等容舒张期 (LVIRT)以及二尖瓣和三尖瓣返流指数 (MR ,TR) ;对照组在相应时间点检测。实验结束后进行心肌损害病理组织学评分。结果　复苏后 6h ,窒息组CK MB和cTnT含量分别为 ( 4 2 3± 156)IU/L和 ( 0 85± 0 64) μg/L ,高于对照组 [( 2 13± 3 0 )IU/L和 ( 0 0 8± 0 0 2 ) μg/L ,P均 <0 0 1] ;LVEF、RVEF、TVE/A、MVe/a和TVe/a分别为 ( 59 6± 8 6) %、( 60 2± 7 1) %、0 79± 0 2 1、0 77± 0 12和 0 78± 0 19,均低于对照组 [分别为 ( 67 5± 6 9) %、( 68 8± 7 4) %、1 14± 0 16、1 19± 0 18和 1 0 3± 0 2 7,P均 <0 0 5] ;心肌损伤病理学评分为 2 82± 0 98,高于对照组 ( 0 3 8± 0 53 ,P <0 0 1) ,且左、右室之间评分无差异。结论　新生猪窒     

Serum total magnesium and ionized calcium concentrations in asphyxiated term newborn infants with hypoxic-ischaemic encephalopathy

Total magnesium, ionized calcium, potassium and sodium concentrations in mixed umbilical cord blood and venous blood serum at a median (min.-max.) age of 33 h (24-48 h) were assessed colorimetrically in 46 asphyxiated and 35 healthy term infants. Asphyxiated infants without any signs or with signs of mild hypoxic-ischaemic encephalopathy (HIE) had significantly higher, and infants with severe HIE lower umbilical cord blood serum total magnesium (mean (95%CI) 0.81 (0.75-0.87) mmol/l and 0.64 (0.47-0.87) mmol/l, respectively, p < 0.05) compared with the control group (0.72 (0.69-0.76)mmol/l). An increase in serum total magnesium in spite of normalized acid-base status in asphyxiated infants suffering from severe HIE compared with the control group infants was found by the second day of life (0.97 (0.87-1.07) mmol/l and 0.86 (0.81-0.9) mmol/l, respectively, p < 0.05). At the age of 24-48 h hypermagnesaemia (>2 SD) was discovered in 36%, hyponatremia (<2 SD) in 38%, and hypocalcaemia (<2 SD) in 23% of asphyxiated infants. Derangements (>2 SD) in at least two electrolytes by the second day of life were significantly associated with poor outcome. CONCLUSIONS: Magnesium, calcium and sodium derangements are a frequent finding in asphyxiated infants, and these abnormalities are significantly associated with poor outcome. For a better outcome prediction, the routine determination of magnesium in addition to other electrolytes in asphyxiated infants is recommended.     

Value of the intravenous route for the use of phenobarbital in asphyxiated full term newborn infants

Phenobarbital (20 mg/kg) was given intravenously to asphyxiated full term neonates who were less than 48 hours old. Further doses were given for 4 days (5 mgs/kg/d). Plasma levels were within the therapeutic range from 5 to 36 hours after the first injection but the maintenance dose always resulted in overdose by 5th day. The exact maintenance dose needs to be determined.     

Neonatal gastrointestinal mucormycosis in an asphyxiated premature newborn

Mucormycosis of the intestine is a rare fungal infection of childhood and is mostly encountered in neonates. It is a potentially lethal opportunistic fungal infection with rapid progression and high mortality in immunocompromised patients. The number of reported cases with intestinal mucormycosis is 19 to date. We herein report an asphyxiated preterm infant with intestinal mucormycosis who was presented with an atypical necrotizing enterocolitis (NEC), with findings similar to an intraabdominal mass. The diagnosis was made in the postmortem examination of the surgically removed bowel segment. Prematurity and asphyxia are important risk factors for mucormycosis. We suggest that the diagnosis of gastrointestinal mucormycosis should be considered in the differential diagnosis of atypical NEC cases.     

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.     

新生儿缺氧缺血性脑病脑血流动力学变化及其临床意义

为研究缺氧缺血性脑病脑血流变化规律，应用彩色多普勒超声对３８例患儿脑血流参数及结构形态进行了连续监测。结果：生后２４小时内，中重度组收缩期、舒张末期及平均血流速度显著下降，分别为２７±６，６±３，１５±４ｃｍ／ｓ，而后逐渐增加，其中以平均血流速度最为明显。脑血管阻力指数及搏动指数开始异常增高，分别为０．８３±０．１２、１．５４±０．２８；４８～９６小时降至最低水平，分别为０．５４±０．０６、０．８０±０．１３，病情愈重二者愈低，脑水肿改变愈明显。轻度组无上述规律。提示：监测脑血管阻力有助于脑损伤的判断与治疗。