早产儿血流动力学及心功能评估的研究进展

早产儿心功能不全是新生儿重症监护室中常见的急危重症,伴随着较高的病死率,可引起严重的近期和远期后遗症。因此了解早产儿血流动力学的主要特点,并准确应用相应的临床监测方法进行早期心功能的评估至关重要。该文将对早产儿血流动力学的主要问题及心功能评估方法作一综述。     

Neonatal arterial hypertension

Neonatal arterial hypertension is usually related to an acquired renovascular disease. An increasing number of cases has been reported during the last 10 years, because of the more frequent survival of very sick neonates and the practice of umbilical arterial catheterization. Improved monitoring of arterial pressure in the infant allows an early diagnosis leading to an efficient medical treatment. Available drugs are now accurate to control arterial hypertension and improving vital prognosis. Later outcome claims for long term survey.     

Abnormal heart rate characteristics preceding neonatal sepsis and sepsis-like illness

Late-onset neonatal sepsis is a significant cause of morbidity and mortality, and early detection could prove beneficial. Previously, we found that abnormal heart rate characteristics (HRC) of reduced variability and transient decelerations occurred early in the course of neonatal sepsis and sepsis-like illness in infants in a single neonatal intensive care unit (NICU). We hypothesized that this finding can be generalized to other NICUs. We prospectively collected clinical data and continuously measured RR intervals in all infants in two NICUs who stayed for >7 d. We defined episodes of sepsis and sepsis-like illness as acute clinical deteriorations that prompted physicians to obtain blood cultures and start antibiotics. A predictive statistical model yielding an HRC index was developed on a derivation cohort of 316 neonates in the University of Virginia NICU and then applied to the validation cohort of 317 neonates in the Wake Forest University NICU. In the derivation cohort, there were 155 episodes of sepsis and sepsis-like illness in 101 infants, and in the validation cohort, there were 118 episodes in 93 infants. In the validation cohort, the HRC index 1) showed highly significant association with impending sepsis and sepsis-like illness (receiver operator characteristic area 0.75, p < 0.001) and 2) added significantly to the demographic information of birth weight, gestational age, and days of postnatal age in predicting sepsis and sepsis-like illness (p < 0.001). Continuous HRC monitoring is a generally valid and potentially useful noninvasive tool in the early diagnosis of neonatal sepsis and sepsis-like illness.     

母亲声音刺激对缓解住院新生儿操作性疼痛的效果观察

目的 探讨母亲声音刺激对于新生儿足跟采血操作性疼痛的影响。方法 将72名新生儿监护室住院新生儿随机分成干预组（n=35）和对照组（n=37）。对照组实施常规的足跟采血操作,干预组在常规操作的基础上于操作前1 min至操作结束播放预先录制的母亲声音。记录两组新生儿穿刺前后的疼痛评分、啼哭发生和生命体征变化情况。结果 与对照组比较,干预组新生儿穿刺过程中的心率显著降低,血氧饱和度显著增高,哭闹发生率和疼痛评分显著降低（P < 0.05）。结论 母亲声音刺激有利于减少新生儿操作性疼痛,保持生命体征稳定。     

The neonatal liver: Part III: Pathophysiology of liver dysfunction

The liver, the largest organ in the body, is critical to a number of key metabolic functions. Its also plays an important role in removing the waste products of metabolism (particularly ammonia) and in detoxifying drugs and other substances such as endogenous hormones and steroid compounds. In addition, the liver plays a major role in the production of clotting factors, plasma proteins, bile salts, and bilirubin. Many neonates display signs of hepatic dysfunction such as hyperbilirubinemia, hepatomegaly, or elevated liver enzymes. These often occur secondary to systemic illness, such as sepsis or hypoxic injury, or following the use of drugs or parenteral nutrition to treat other problems. Although rare, primary liver disease does occur in neonates and must be recognized promptly, with treatment initiated in a timely manner to prevent unnecessary sequelae. This article, the third in a series on the liver, examines causes of liver dysfunction in neonates, beginning with an overview of jaundice and hepatomegaly and moving to a discussion of specific diseases.     

Child with absent vital signs

The outcome of cardiopulmonary resuscitation in the child with absent vital signs is dismal. Best outcomes therefore should rely on early recognition and aggressive management of critical illness to interrupt deterioration to cardiorespiratory arrest. Moreover, resuscitation entails a spectrum of care starting with cardiopulmonary resuscitation at the site of injury through critical care and post resuscitation rehabilitation. The resources required to provide this level of care is not available in many parts of the world. Therefore, resuscitation skills should be taught to caregivers at a level which is congruent to their role in the continuum of care and the use of aggressive resuscitation needs to be tailored based on geography, risk to medical personnel, preservation of resources, transplantation issues and expected outcomes. In some cases, the most prudent decision may be not to attempt resuscitation of the child with absent vital signs.     

Human herpesvirus-6 infection in neonates: Not protected by only humoral immunity

BACKGROUND: Infants are usually protected from various viral infections, including human herpesvirus-6 (HHV-6) and human herpesvirus-7 (HHV-7) infections, during the early infantile period by antibodies transferred from their mothers. However, rare cases of exanthem subitum (ES) in neonates have been described in published reports. METHODS: From the infantile patients of febrile illness, HHV-6 and HHV-7 DNA were examined by the polymerase chain reaction method. Antibodies to HHV-6 and HHV-7 were detected by indirect immuno-fluorescence assay and neutralization test. Viral isolation was attempted from the patient's peripheral blood mononuclear cells (PBMC) during the acute phase of febrile illness. RESULTS: Human herpesvirus-6 was verified virologically in two neonates who were clinically diagnosed as ES within the first month of life. Although high copies of HHV-6 DNA were detected in their PBMC during the acute phase, the isolation of HHV-6 from their PBMC was not successful. Neutralizing antibodies to HHV-6 were detected in sera of the acute phase, and those antibodies were considered to be transferred from their mothers. Antibody titers showed fourfold elevation in sera of the convalescent phase. The HHV-6 infection occurred despite the presence of pre-existing maternal antibody. Human herpesvirus-7 and HHV-7 DNA were not detected from their clinical samples. CONCLUSIONS: This observation suggests that HHV-6 infection could not be protected by only humoral immunity.     

Morphine for elective endotracheal intubation in neonates: a randomized trial [ISRCTN43546373]

Background  

Elective endotracheal intubations are still commonly performed without premedication in many institutions. The hypothesis tested in this study was that morphine given prior to elective intubations in neonates would decrease fluctuations in vital signs, shorten the duration of intubation and reduce the number of attempts.     

Value of approach monitoring of infusion pressure in neonatology]

The consequences of catheter occlusions are particularly dangerous in neonates. For early detection and to efficiently prevent such occlusions, the monitoring of infusion pressure by a variable pressure pump is reported. Two ways of monitoring can be recommended: easy viewing of infusion pressure and programming a pressure limit. Infusion pressure is recorded at around +/- 30 cm water pressure of the mean day pressure. Consequently, a rise above this gap must be considered as suspect. The regular viewing of this measurement is a way of predicting such problems as occlusions. The optimum pressure limit is programmed at 30 cm water pressure above the infusion pressure. This alarm may identify the beginning of occlusions or reduce the extent of tissue damage in early detecting of an infiltration.     

Clinical and echocardiographic diagnosis of patent ductus arteriosus in premature neonates

The ductus arteriosus frequently fails to close in premature neonates. Considerable difference in opinion exists around what signifies a hemodynamically significant patent ductus arteriosus (PDA) and how reliable clinical signs are in determining the degree of the left-to-right shunting. Although reliance on clinical signs alone could delay the diagnosis of a PDA, there is insufficient evidence to suggest that early treatment improves outcome. Echocardiography is often used as the gold standard for diagnosing a PDA. A combination of echocardiographic measurements may assist in the early diagnosis of a PDA with a hemodynamically significant degree of left-to-right shunting, especially in extremely premature babies, where closure can be significantly delayed. Decision to treat PDA should be based on a combination of clinical signs and echocardiographic parameters. Monitoring B-type natriuretic peptide may be useful in the diagnosing neonates with symptomatic PDA.     

Diagnostic and prognostic utility of C-reactive protein, alpha-1-antitrypsin and alpha-2-macroglobulin in neonatal sepsis: a comparative account.

C-reactive protein (CRP), alpha-1-antitrypsin (alpha-1-AT) and alpha-2-macroglobulin (alpha-2-MG) levels were evaluated serially in 25 healthy and 20 septicemic neonates and then compared as early diagnostic aids and prognostic indicators in this illness. Compared to healthy controls, septicemic neonates had significantly higher mean CRP levels (p less than 0.01). Neonates with septicemia, who recovered, had higher mean CRP levels than the group which died (p less than 0.05). As an early diagnostic aid CRP had a low Youden index, whereas for prognosis its index was higher. Septicemic neonates also had significantly higher mean alpha-1-AT levels (p less than 0.05), 12-24 hours after onset of illness, as compared to healthy neonates. Alpha-1-antitrypsin could not be used as an early diagnostic aid in septicemia, but was useful for predicting outcome. Mean alpha-2-macroglobulin levels did not show significant variation in healthy and septicemic neonates. Lower mean alpha-2-MG levels were observed in neonates recovering from septicemia. As an early diagnostic aid alpha-2-MG had a low Youden index, whereas for prognosis its index was higher. CRP had a higher Youden index than alpha-2-MG for early diagnosis of neonatal septicemia and had a higher index than both alpha-1-AT and alpha-2-MG for predicting outcome in septicemia. Serial use of CRP alone is, therefore, recommended for both purposes.     

Critical appraisal of the management of severe malnutrition: 3. Complications

Abstract:   The high case-fatality of severe malnutrition is due to infections, dehydration, electrolyte disturbances and heart failure. We focus on the evidence about managing these complications of severe malnutrition. Signs of circulatory collapse in severely malnourished children should be treated with intravenous or bone marrow infusion of Ringer's lactate with additional dextrose and potassium at a rate 20–40 mL/kg fast with close monitoring of vital signs. Recommendations for slow or restricted fluids in the face of shock are unsafe, and hypotonic or maintenance solutions must be avoided to prevent hyponatraemia. However, the evidence that severely malnourished children do not tolerate excessive fluid administration is good, so caution must be exercised with regards to fluids in the initial phase of treatment. There is also good evidence that wide spectrum antibiotics need to be given empirically for severe malnutrition to prevent the otherwise unavoidable early mortality. There is a need for improved protocols for tuberculosis diagnosis, HIV management and treatment of infants under 6 months with severe malnutrition. The contribution of environmental enteropathy to poor growth and nutrition during the weaning period means that there should be more priority on improving environmental health, particularly better hygiene and less overcrowding. A T-cell mediated enteropathy contributes to growth failure and malnutrition, and it is related to environmental contamination of enteric organisms in the weaning period rather than allergic responses.     

A case of kernicterus in New Zealand: A predictable tragedy?

Abstract: A case of neonatal kernicterus due to glucose-6-phosphate dehydrogenase deficiency (G6PD) is described. Diagnosis was delayed as the primary healthcare attendant had no knowledge of this condition and its potential to cause rapidly escalating levels of bilirubin and as she was reassured by the lack of signs of systemic illness or anaemia. The baby has been left deaf, blind, intellectually handicapped, epileptic and paralysed due to athetoid cerebral palsy. The re-organization of perinatal care in New Zealand, which has ted to neonates sometimes being managed solely by primary healthcare attendants with minimal training in paediatrics may have increased the risk of a late diagnosis of potentially devastating diseases such as this.     

Hepatomegaly in neuroblastoma stage 4s: Criteria for treatment of the vulnerable neonate

Infants with neuroblastoma (NBL) frequently present as stage 4s and overall, such patients have a good prognosis. However, not all survive, and neonates with hepatomegaly are particularly at risk. We therefore reviewed our 4s experience, the objective being to identify lethal patterns of disease progression. The specific aims of this work were (1) to develop a semiquantitative scoring system based on the severity of signs and symptoms that alone or in combination presaged a fatal outcome, and (2) to determine if early intervention could reverse life-threatening disease. Thirty-five patients were seen over a period of 50 years. The signs and symptoms of organ distress caused by hepatomegaly occurred in the lungs, kidneys, gastrointestinal tract (GI), the inferior vena cava (IVC), and the liver. A scoring scale reflecting organ compromise was developed, the scores ranging from 0 (0 compromise) to 10 (all 5 systems showing evidence of impairment). Scores were derived for 32 of 35 patients; 13 were 4 weeks old or under (neonates) when first seen, and 19 were aged 1–12 months (infants). Neonates were more likely than infants to develop increasing symptomatology (50% versus 25%) and were more likely to die when a score of 2 or more developed. None of the 6 neonates who did so survived despite treatment, compared with three of four infants. Early intervention is recommended: (1) for 4s neonates who develop a score of 1 and (2) for older infants with a score ≥2. © 1996 Wiley-Liss, Inc.     

Perinatal biomarkers implying ‘Developmental Origins of Health and Disease’ consequences in intrauterine growth restriction

The intrauterine-growth-restricted (IUGR) state, particularly the asymmetric one, has been associated with ‘Developmental Origins of Health and Disease’ (DOHaD) consequences later in life. Several environmental factors, acting during the phase of foetal developmental plasticity interact with genotypic variation, ‘programme’ tissue function and change the capacity of the organism to cope with its environment. They may be responsible for chronic illness risk in adulthood. Detection of possible future DOHaD consequences at a very early age, by applying relevant biomarkers, is of utmost importance. This review focuses on biomarkers possibly predicting consequences from bone, psychoneural system and lung. Although no concrete biomarker has been identified for bone disorders in adulthood, reduced brain-derived neurotrophic factor (BDNF) concentrations in cord blood and BDNF DNA methylation might predict schizophrenia and possibly depression, bipolar disorder and autism. High surfactant protein D (SP-D) concentrations in cord blood of IUGR foetuses/neonates could point to structural lung immaturity, resulting to asthma and chronic obstructive pulmonary disease in adult life.     

GROUP B STREPTOCOCCAL INFECTION IN THE NEWBORN Criteria for Early Detection and Treatment

Abstract. Recent reports indicate that the group B haemolytic streptococcus has now assumed a major role in neonatal septicaemia in the United Kingdom. Of particular concern are the absence of premonitory signs, the fulminating nature of the infection and the high mortality. 31 cases from which this organism was isolated during the first week of life included 5 cases of neonatal septicaemia, 4 of which proved fatal. An attempt was made ( a ) to identify the group of neonates at greatest risk and ( b ) to formulate guidelines for early detection and treatment. Study indicates the importance of apnoea as a sign of infection particularly in those infants who are preterm, of low birth weight and asphyxiated. There is need for aggressive bacteriological screening and early administration of antibiotics to prevent the high mortality from group B streptococcal infection.     

Amebic liver abscesses among neonates can mimic bacterial sepsis

Amebic liver abscesses are unusual among neonates. Three (3.6%) of 83 children who presented to a university hospital with amebic liver abscesses in a 17-year period were neonates (<28 days of age). Patients presented with nonspecific clinical and laboratory findings mimicking fulminant neonatal sepsis. Diagnosis was delayed and was based on the presence of a hypoechoic lesion in the liver, antibodies against Entamoeba histolytica and microbiologic examination of pus. In addition to parenteral metronidazole treatment and early ultrasound-guided aspiration of the abscess, intensive care is vital for the treatment of neonates with amebic liver abscesses.     

Management of dengue fever in ICU

Dengue virus infection can cause a wide spectrum of illness. Thrombocytopenia with concurrent haemoconcentration differentiates dengue haemorrhagic fever from classical dengue fever. Only cases with shock or unstable vitals signs need admission in the pediatric intensive care. The management is essentially supportive and symptomatic. The key to success is frequent monitoring and changing strategies. A rise in hematocrit of 20% along with a continuing drop in platelet count is an important indicator for the onset of shock. Patients in grade I and II should be closely monitored for signs of shock. The management of dengue shock syndrome (grade III and IV) is a medical emergency needing prompt and adequate fluid replacement for the rapid and massive plasma losses through increased capillary permeability. Early and effective replacement of plasma losses with plasma expanders or fluid and electrolyte solutions results in a favourable outcome in most cases. The ideal fluid management should include both cystalloids and colloids (including albumin). Cystalloids are given as boluses as rapidly as possible, and as many as 2 to 3 boluses may be needed in profound shock. Colloidal fluids are indicated in patients with massive plasma leakage and in whom a large volume of cystalloids has been given. Frequent recording of vital signs and determinations of haematocrit are important in evaluating the results of treatment. Apart from correction of electrolyte and metabolic disturbances, oxygen is mandatory in all patients of shock. Some patients develop DIC and need supportive therapy with blood products (blood, FFP and platelet transfusions). Polyserositis, in the form of pleural effusion and ascitis, are common in cases of dengue shock syndrome, and if possible, drainage should be avoided as it can lead to severe hemorrhages and sudden circulatory collapse. The prognosis depends mainly on the early recognition and treatment of shock.     

Early detection of necrotizing enterocolitis by gastrointestinal tonometry

The diagnosis of necrotizing enterocolitis (NEC) in neonates has traditionally depended on a combination of clinical signs, biochemical parameters and radiological changes. The measurement of intramucosal pH by gastrointestinal tonometry provides a simple means of long-term monitoring which may detect the development of NEC before conventional techniques. We present our experience of tonometry in two'at risk'term neonates with Hypoplastic Left Heart Syndrome.