Efficacy of bowel ultrasound to diagnose necrotizing enterocolitis in extremely low birthweight infants.

BACKGROUND: Bowel ultrasound (US) is one of the methods used to enhance diagnostic accuracy of necrotizing enterocolitis (NEC) and its associated complications in premature newborns. AIM: To explore the diagnostic accuracy of bowel US in extremely low birth weight (ELBW) infants with NEC. METHODS: A single-center retrospective case-control study included 84 extremely low birth weight (ELBW) infants. The infants were divided into three groups: Group 1 -infants with NEC (n = 26); Group 2 -infants with feeding problems (n = 28); Group 3 -control group (n = 30). RESULTS: The specific bowel US findings in premature newborns with NEC (stage 3) included bowel wall thinning, complex (echogenic) ascites, and pneumoperitoneum, p < 0.05. The diagnostic effectiveness of these sonographic signs was 96.8% (sensitivity 75.0% and specificity 97.6%), p < 0.05. These findings with high specificity were associated with the need for surgical intervention, poor outcomes, or increased mortality. Stage 2 NEC which did not require surgery showed impaired differentiation of the bowel wall layers, absent or decreased bowel peristalsis, pneumatosis intestinalis, portal venous gas, or simple ascites, with a diagnostic accuracy of 82.9% (sensitivity 55.6%, specificity 91.4%, p < 0.05). CONCLUSIONS: Bowel US can be used as an adjunct to abdominal radiography to aid in the diagnosis of infants with suspected NEC by providing more detailed evaluation of the intestine.

Multiple vascular malformations in a newborn.

We describe the case of a term newborn who presented with congenital testicular torsion at 10 hours of age. During the evaluation of this problem, additional malformations were encountered. Diagnostic and therapeutic considerations are addressed.

The challenging airway: Tracheal agenesis in the newborn.

A preterm female presented with severe respiratory distress in the delivery room and was found to have tracheal agenesis with a tracheoesophageal fistula and a congenital heart defect. Tracheal agenesis is uncommon and is often associated with other congenital abnormalities. Although there are surgical options for repair, mortality remains high.

Recurrent late-onset neonatal sepsis traced to breast milk: A case report.

Breast milk feeding is an important late-onset sepsis reduction strategy in the Neonatal Intensive Care Unit (NICU). However, multiple studies have reported transfer of bacteria-contaminated breast milk to infants. We describe a case of culture-positive breast milk resulting in persistent Enterococcus bacteremia in an infant. Beyond the development of an infant's innate and specific immunity as well as colonization of the gastrointestinal (GI) tract with commensal organisms, the risk of bacterial translocation from the GI tract into the bloodstream is shaped and modified by maternal health, birth history, and an infant's NICU course. While freezing and/or pasteurizing breast milk reduces or eliminates its bacterial load, it also diminishes its immunologic and nutritional benefits.

Rescue high frequency ventilation for congenital diaphragmatic hernia.

INTRODUCTION: High frequency jet (HFJV) and oscillatory (HFOV) ventilation were used to rescue newborns with congenital diaphragmatic hernia (CDH), who failed conventional mechanical ventilation (CV). Changes in ventilator settings and pulmonary gas exchange were evaluated following transition to high frequency ventilation (HFV). METHODS: Records of patients with CDH rescued with HFV prior to surgical intervention between 2006 and 2015 were reviewed. Mean airway pressure (Paw) and arterial blood gases during CV and those obtained within the first hour of HFV were compared. A composite repeated measure analysis was performed to evaluate longitudinal and intergroup variances. RESULTS: Twenty-seven patients were rescued from CV, 16 by HFJV and 11 by HFOV. The two groups had similar gestational ages and birth weights. Prior to HFV, both groups had similar Paw, PaCO2, FiO2 and PaO2. HFV was associated with a significant improvement in ventilation, and the rate of decrease of PaCO2 was no different between groups. There was a significantly higher increase in Paw increase with HFOV compared to HFJV. CONCLUSIONS: In newborns with CDH rescued with HFV, ventilation improved but Paw was significantly lower in patients supported with HFJV compared to HFOV.

Medico-legal implications of hypothermic neuroprotection in the newborn.

Hypoxic-ischemic encephalopathy (HIE) continues to be a significant source of long term neurological sequelae in infants born at or near term. In the past decade, selective head or whole body cooling has shown promising benefit in ameliorating some of the brain injury from intrapartum asphyxial insults and has become standard care in most developed countries. A decision to offer neuroprotective hypothermia (NPH) may engender subsequent litigation because it presupposes an acute intrapartum injury. Conversely, failing to offer cooling may be interpreted as a violation in the standard of care. In this paper, we review the clinical aspects of NPH and the medico-legal scenarios often seen after acute birth injury.

Impact of warmed inhaled gas from the mechanical ventilator on esophageal temperature during therapeutic whole body hypothermia.

OBJECTIVE: During therapeutic whole body cooling (WBC), the core temperature is usually monitored with an esophageal probe. Most infants receive mechanical ventilation while being cooled. As the temperature in the esophagus responds rapidly to changes in the ambient temperature, inhalation of warmed gas from ventilator may lead to overestimation of ventilated patients' actual temperature, causing automated cooling devices to overcool patients well below the desired set temperature targets. To determine if the esophageal temperature recordings during therapeutic WBC differ between ventilated and non-ventilated infants. STUDY DESIGN: Twenty-two consecutively cooled infants had simultaneous esophageal and rectal temperatures recorded every 4 h during 72 h of WBC. Other clinical monitoring and treatment during hypothermia were provided under an established protocol. RESULTS: Fourteen infants received mechanical ventilation throughout the duration of cooling. The remaining eight infants were initially ventilated but were extubated later and were not on ventilator between 32 and 72 h of WBC. The esophageal temperatures across every 4 h time points during the 32-72 h interval of WBC did not differ between the ventilated and non-ventilated infants. The magnitude (median, interquartile range) of the difference between esophageal and rectal temperatures was also similar between the two groups. CONCLUSION: Warmed inhaled gas does not interfere with the esophageal temperature during WBC.

Does clinical status 1 week after therapeutic hypothermia predict brain MRI abnormalities?

OBJECTIVE: Hypothermia improves clinical outcomes and brain magnetic resonance imaging (MRI) findings in infants with hypoxic-ischemic encephalopathy. We hypothesized that clinical status following hypothermia predicts brain MRI abnormalities, and helps determine which infants need an early MRI evaluation before discharge. The objective of this study was to determine whether the clinical evaluation 1 week after completion of 72 h of hypothermia treatment predicts the presence of brain MRI abnormalities related to hypoxia-ischemia. STUDY DESIGN: The medical records of 83 consecutively cooled infants who underwent brain MRI were reviewed. Clinical evaluation by day 10 of life consisted of assessment of oral feeding ability, spontaneous activity, need for mechanical ventilation and a history of clinical seizures. Logistic regression analysis was performed using all four covariates, with an abnormal MRI as the primary outcome. Brain MRI with lesions in both the basal nuclei and the cortex was considered to be severely abnormal. RESULT: MRI was abnormal in 46 (55%) infants. Univariate analysis identified all of the criteria as being significantly associated with an abnormal MRI. On multivariate analysis, only feeding difficulty (P<0.001, OR 9.5, 95% confidence interval (CI) 3 to 29.8) and a history of clinical seizures (P<0.001, OR 12, 95% CI 3 to 46.5) were significantly associated with an abnormal MRI. The areas under the receiver operating characteristic curve for feeding ability and seizure activity combined (0.86, 95% CI 0.77 to 0.94) indicated good accuracy with respect to the primary outcome. The negative predictive values of feeding difficulty and seizure activity for a severely abnormal MRI were 91% and 96%, respectively. CONCLUSION: Infants who do not have a history of clinical seizures and who attained full oral feeding by 1 week after hypothermia are unlikely to have an abnormal brain MRI. This simple assessment provides significant prognostic information that can be useful in parental counseling, and may allow selective use of pre-discharge MRI.

Does phenobarbital improve the effectiveness of therapeutic hypothermia in infants with hypoxic-ischemic encephalopathy?

OBJECTIVE: To determine whether phenobarbital (PB) given before therapeutic hypothermia to infants with hypoxic-ischemic encephalopathy (HIE) augments the neuroprotective efficacy of hypothermia. STUDY DESIGN: Records of 68 asphyxiated infants of 36 weeks' gestation, who received hypothermia for moderate or severe HIE were reviewed. Some of these infants received PB prophylactically or for clinical seizures. All surviving infants had later brain magnetic resonance imaging (MRI). The composite primary outcome of neonatal death related to HIE with worsening multiorgan dysfunction despite maximal treatment, and the presence of post-hypothermia brain MRI abnormalities consistent with hypoxic-ischemic brain injury, were compared between the infants who received PB before initiation of hypothermia (PB group, n=36) and the infants who did not receive PB before or during hypothermia (No PB group, n=32). Forward logistic regression analysis determined which of the pre-hypothermia clinical and laboratory variables predict the primary outcome. RESULT: The two groups were similar for severity of asphyxia as assessed by Apgar scores, initial blood pH and base deficit, early neurologic examination, and presence of an intrapartum sentinel event. The composite primary outcome was more frequent in infants from the PB group (PB 78% versus No PB 44%, P=0.006, odds ratio 4.5, 95% confidence interval 1.6 to 12.8). Multivariate analysis identified only the PB receipt before initiation of hypothermia (P=0.002, odds ratio 9.5, 95% confidence interval 2.3 to 39.5), and placental abruption to be independently associated with a worse primary outcome. CONCLUSION: PB treatment before cooling did not improve the composite outcome of neonatal death or the presence of an abnormal post-hypothermia brain MRI, but the long-term outcomes have not yet been evaluated.

Neonatal ventilators: how do they differ?

Remarkable technological advances over the past two decades have brought dramatic changes to the neonatal intensive care unit. Microprocessor-based mechanical ventilation has replaced time-cycled, pressure-limited, intermittent mandatory ventilation with almost limitless options for the management of respiratory failure in the prematurely born infant. Unfortunately, much of the infusion of technology occurred before the establishment of a convincing evidence base. This review focuses on the basic principles of mechanical ventilation, nomenclature and the characteristics of both conventional and high-frequency devices.

Long term follow-up of very low birthweight infants from a neonatal volume versus pressure mechanical ventilation trial.

BACKGROUND: A previous randomised trial showed volume controlled ventilation (VCV) was efficacious in ventilating very preterm and extremely low birthweight babies. OBJECTIVE: To compare long term survival, pulmonary morbidities and gross neurodevelopmental outcomes of babies randomised to either VCV or pressure limited ventilation (PLV) for treatment of respiratory distress syndrome. DESIGN/METHODS: Masked evaluation of health status, including frequency of respiratory illness, use of medications, hospital admissions, and gross neurodevelopmental status were obtained using a structured parental questionnaire and verification from medical records. RESULTS: 94 of 109 children (86%) survived to discharge. Three died after discharge (2 VCV, 1 PLV). Modality of ventilation did not affect overall mortality; seven VCV children died (12%) versus 11 PLV (21%) (OR 0.5 (95% CI 0.1 to 1.4), p = 0.13). Respiratory abnormalities were present in 32 (37%), and 26 (30%) required hospital readmission. There was no significant difference in readmission rates between the two groups: VC 13/45 (29%) and PLV 19/40 (47%) (OR 0.4 (0.1 to 1.1), p = 0.07). Modality of ventilation did not affect frequency of respiratory illness: VC 12 (27%) and PLV 14 (35%) (OR 0.46 (0.1 to 1.1), p = 0.09). However, significantly fewer VCV children (13%, n = 6) compared to PLV children (32%, n = 13) required treatment with inhaled steroids/bronchodilators (OR 0.3 (0.1 to 0.9), p = 0.04). Nine children had severe neurodevelopmental disability (cerebral palsy, blindness, deafness) (9.8%; 3 VCV, 6 PLV 6) (OR 0.4 (0.09 to 1.7)). CONCLUSIONS: The efficacy of VCV in very preterm and low birth babies appears to be maintained on longer term evaluation.

Effects of therapeutic hypothermia on multiorgan dysfunction in asphyxiated newborns: whole-body cooling versus selective head cooling.

OBJECTIVE: Multiorgan dysfunction in asphyxiated newborns receiving therapeutic hypothermia achieved by either selective head cooling (SHC) or whole-body cooling (WBC) has not been well characterized. The beneficial effect of SHC in organs other than the brain may potentially be limited because unlike WBC, SHC aims to achieve effective brain cooling with less-systemic hypothermia. However, the relative effects of SHC and WBC with currently available cooling protocols on multiorgan dysfunction are unknown.The aim of this study was to compare the multiorgan dysfunction in infants receiving therapeutic hypothermia induced by either SHC or WBC. STUDY DESIGN: In 59 asphyxiated newborns who received therapeutic hypothermia by either SHC (n=31) or WBC (n=28), the severity of pulmonary, hepatic and renal dysfunction and coagulopathy and electrolyte disturbances were assessed before the start of cooling (baseline), and at specific time intervals (24, 48 and 72 h) throughout cooling. Enrollment criteria, clinical monitoring and treatment during cooling, whether SHC or WBC, were similar, as reported earlier. RESULT: The presence of clinical respiratory distress, along with the need for ventilatory support for varying duration during cooling, was similar in both the WBC and SHC groups (100 vs 94%, P=0.49, OR 1.9, 95% CI 1.5-2.5). The use of fresh frozen plasma and platelet transfusion to treat coagulopathy and thrombocytopenia was similar (WBC 48% vs SHC 58%, P=0.59, OR 0.7, 95% CI 0.2-1.9, and WBC 41% vs SHC 32%, P=0.58, OR 1.4, 95% CI 0.5-4.2, respectively), and equivalent numbers of infants from both groups were treated with vasopressors for >24 h (WBC 59% vs SHC 55%, P=0.79, OR 1.2, 95% CI 0.4-3.4). The incidence of oliguria (urine output <0.5 ml kg(-1) h(-1) for >24 h after birth) and rising serum creatinine (with maximum serum creatinine >0.9 mg dl(-1)) was also similar (WBC 18% vs SHC 39%, P=0.15, OR 0.4, 95% CI 0.1-1.3, and WBC 48% vs SHC 58%, P=0.59, OR 0.7, 95% CI 0.2-1.9, respectively). Laboratory parameters to assess the differential effect of WBC versus SHC on multiorgan dysfunction during 72 h of cooling, which include serum transaminases (serum aspartate aminotransferase and alanine aminotransferase), prothrombin time, partial thromboplastin time, INR, platelet counts, serum creatinine, serum sodium, serum potassium and serum calcium, were similar between the groups at the initiation of cooling and did not differ with the method of cooling. CONCLUSION: Multiorgan system dysfunction in asphyxiated newborns during cooling remains similar for both cooling methods. Concerns regarding a differential effect of WBC versus SHC on multiorgan dysfunction, other than of the brain, should not be a consideration in selecting a method to produce therapeutic hypothermia.

The effect of two levels of pressure support ventilation on tidal volume delivery and minute ventilation in preterm infants.

OBJECTIVE: To study the effect of different levels of pressure support ventilation (PSV) on respiratory parameters in preterm infants during the weaning phase of mechanical ventilation. DESIGN/METHODS: In this quasi-experimental crossover study, a total of 19 154 breaths were analysed from 10 ventilated infants of <32 weeks' gestation. Breath-to-breath data on minute ventilation, tidal volume, respiratory rate, peak inspiratory pressure and mean airway pressure were collected during three study epochs: synchronised intermittent mandatory ventilation (SIMV) alone, SIMV with partial PSV (PS(min)), and SIMV with full PSV (PS(max)). PS(min) was set to provide an exhaled tidal volume (V(Te)) between 2.5-4 ml/kg and PS(max) 5-8 ml/kg V(Te). Statistical analyses were performed using analysis of variance (ANOVA) for repeated measures. RESULTS: The addition of full PSV (PS(max)) was associated with a significant increase in total minute ventilation as compared with SIMV alone (392 ml/kg/min vs 270 ml/kg/min, respectively; p<0.05). This difference in minute ventilation was still present when PS(min) was used (332 ml/kg/min as compared with 270 ml/kg/min in SIMV; p<0.05). There was also a concomitant decrease in the respiratory rate with both PS(max) (59 breaths per minute) and PS(min) (65 breaths per minute) compared with SIMV alone (72 breaths per min) (p<0.05). CONCLUSIONS: Pressure support ventilation increases total minute ventilation and stabilises breathing in proportion to the level of pressure support used. This may be advantageous and provide a useful ventilation strategy for use during weaning stages of mechanical ventilation in preterm infants.

Should amplitude-integrated electroencephalography be used to identify infants suitable for hypothermic neuroprotection?

OBJECTIVE: Amplitude-integrated electroencephalography (aEEG) has been used adjunctively to identify infants suitable for hypothermic neuroprotection following severe intrapartum asphyxia. To determine whether an early aEEG predicts short-term adverse outcome in infants with significant hypoxic-ischemic encephalopathy (HIE) evaluated for hypothermic neuroprotection. STUDY DESIGN: The aEEG recordings were obtained within 6 h of birth in infants >or=36 weeks' gestational age during evaluation for possible selective head or whole-body cooling. Recordings were subsequently re-evaluated for both background pattern and voltage abnormalities by a certified reader masked to clinical history and brain-oriented interventions. All infants with moderate or severe HIE evaluated for hypothermic neuroprotection also underwent magnetic resonance imaging (MRI) of the brain at a median postnatal age of 7 days. The predictive value using the aEEG for determining short-term dichotomous outcomes, defined as early death related to HIE, or a characteristic pattern of abnormalities consistent with hypoxic-ischemic injury on the MRI brain scans was assessed. RESULT: Fifty-four infants with moderate or severe HIE were evaluated with aEEG for hypothermic neuroprotection; 34 infants received selective head cooling, 12 infants underwent total body cooling and 8 infants were not cooled. Outcome data, available for 46 of the 54 infants, revealed a poor correlation between the early aEEG and short-term adverse outcomes, with a sensitivity of 54.8% and negative predictive value (NPV) of only 44%. CONCLUSION: Because of the poor NPV of an early aEEG for a short-term adverse outcome, its use as an 'additional selection criterion' for hypothermic neuroprotection may not be appropriate.

Is refractory hypotension in preterm infants a manifestation of early ductal shunting?

BACKGROUND: Clinicians frequently use hydrocortisone (HC) to treat vasopressor-resistant hypotension even before establishing its cause. OBJECTIVE: To identify the etiologic factors leading to development of refractory hypotension, and to assess if patent ductus arteriosus (PDA) is associated with refractory hypotension during the first week of life. STUDY DESIGN: The medical records of 290 consecutively born infants

Can neutrophil responses in very low birth weight infants predict the organisms responsible for late-onset bacterial or fungal sepsis?

OBJECTIVE: To examine neutrophil counts and various neutrophil indices in preterm very low birth weight (VLBW) newborn infants (birth weight <1500 g) with culture-proven late-onset sepsis to determine whether the neutrophil responses could predict the responsible infectious agent. STUDY DESIGN: Neutrophil parameters were examined during episodes of culture-proven sepsis in a cohort of 1026 VLBW infants, born over a 6-year period and admitted to two different neonatal intensive care units. Revised reference ranges of Mouzinho et al. for circulating neutrophil counts in VLBW infants were used to define the abnormal neutrophil indices. RESULTS: One hundred sixty-two of 1026 (15.8%) VLBW infants had blood culture-proven late-onset infection. Infections included Gram-positive bacteria (113/162, 70%), Gram-negative bacteria (30/162, 18%) and fungi (19/162, 12%). Of the 162 sepsis episodes, only nine (5.5%) were associated with neutropenia (absolute total neutrophil (ATN) <1100/mm3). Six of the 30 (20%) infants with Gram-negative bacterial sepsis were neutropenic compared to 2.6% infants with Gram-positive bacterial sepsis and none with fungal sepsis (odds ratio: 11; 95% confidence interval: 2.6, 47.3). Neutrophil counts and various neutrophil indices were similar in infants with late-onset Gram-positive bacterial and fungal sepsis; but total white blood cells, and ATN count were significantly lower (P = 0.004 and 0.001, respectively) in infants with late-onset Gram-negative bacterial sepsis. CONCLUSIONS: In VLBW infants, common organisms causing infection have different effects on neutrophil responses. Occurrence of neutropenia during evaluation of sepsis in sick VLBW infants is more common with Gram-negative bacterial infection.

Are newborns receiving premedication before elective intubation?

AIMS: To determine the extent and type of premedication used for elective endotracheal intubation in neonatal intensive care units (NICUs). METHODS: A pretested questionnaire was distributed via e-mail to the program directors of the neonatology divisions with accredited fellowship programs in Neonatal-Perinatal Medicine in the United States. RESULTS: Of the 100 individuals contacted, 78 (78%) participated in the survey. Only 34 of the 78 respondents (43.6%) always use any premedication for elective intubation. Nineteen respondents (24.4%) reported to have a written policy regarding premedication. Morphine or fentanyl was used most commonly (57.1%), with a combination of opioids and midazolam or other benzodiazepines used less frequently. Fourteen respondents (25%) also use muscle relaxants with sedation for premedication, but only nine respondents combined paralysis with atropine and sedation. CONCLUSION: Most neonatology fellowship program directors do not report always using premedication for newborns before elective endotracheal intubation despite strong evidence of physiologic and practical benefits. Only a minority of the NICUs has written guidelines for sedation, which may preclude effective auditing of this practice. Educational interventions may be necessary to ensure changes in clinical practice.

Minimising ventilator induced lung injury in preterm infants.

Ventilator induced lung injury continues to occur at an unacceptably high rate, which is inversely related to gestational age. Although the "new BPD" may not be entirely avoidable in the extremely premature infant, recognition of risk factors and adoption of an appropriate ventilatory strategy, along with continuous real time monitoring, may help to minimise lung damage. This paper will review the pathogenesis of ventilator induced lung injury and strategies that may mitigate it.

Management of neonatal abstinence syndrome in neonatal intensive care units: a national survey.

AIMS: To determine the monitoring and treatment of neonatal abstinence syndrome (NAS) in neonatal intensive care units (NICUs) following opiate or polydrug exposure in utero. METHODS: A pretested questionnaire was distributed via email to the chiefs of the neonatology divisions with accredited Fellowship programs in Neonatal-Perinatal Medicine in the United States. RESULTS: Of the 102 individuals contacted, 75 participated in the survey. In all, 41 of the respondents (54.5%) have a written policy regarding the management of neonatal NAS. The method of Finnegan is the most commonly used abstinence scoring system (49 of 75, 65%), while only three respondents use the Lipsitz tool. Opioids (tincture of opium, or morphine sulfate solution) are used most commonly for management of both opioid (63% of respondents) and polydrug (52% of respondents) withdrawal, followed by phenobarbital (32 % of respondents) for polydrug withdrawal and methadone (20% of respondents) for opioid withdrawal. In all, 53 respondents (70%) use phenobarbital, and 19 (25%) use intravenous morphine to control opioid withdrawal seizures, while 61 (81%) use phenobarbital in cases of polydrug withdrawal seizures. Only 53 respondents (70%) always use an abstinence scoring system to determine when to start, titrate, or terminate pharmacologic treatment of neonatal NAS. CONCLUSION: The management of neonatal psychomotor behavior consistent with withdrawal varies widely, with inconsistent policies to determine its presence or treatment. Only about half of NICUs have written guidelines for the management of NAS, which may preclude effective auditing of this practice. Educational interventions may be necessary to ensure changes in clinical practice.

Volume-controlled ventilation. Variations on a theme.

Development of sophisticated transducers and microprocessor-based ventilators now enables the performance of volume-controlled ventilation of newborn infants. Volume-controlled modes include standard intermittent or synchronized intermittent mandatory ventilation; assist-control ventilation; and hybrid modes, such as pressure-support ventilation, pressure-regulated volume-control ventilation, volume-assured pressure support, and volume guarantee. This article describes the concepts and clinical applications of these ventilatory modes.