Influence of antiepileptic drugs on amplitude-integrated electroencephalography

The Association of Therapeutic Hypothermia With Seizure Burden in Neonates With Hypoxic-Ischemic Encephalopathy

OBJECTIVES

To compare seizure burden between newborn infants treated with therapeutic hypothermia (TH) and those that were not and to compare the need for antiseizure medications (ASM) in a cohort of infants who were diagnosed with neonatal hypoxic-ischemic encephalopathy (HIE).

METHODS

This was a retrospective cohort study on infants born after 35 weeks' gestation, diagnosed with moderate to severe HIE, monitored with amplitude-integrated electroencephalography (aEEG) and eligible for TH. Infants born before the implementation of TH in 2008 were compared with infants born thereafter who received TH. Seizure burden was assessed from aEEG as total time in minutes of seizures activity per hour of recording. Other clinical and demographic data were retrieved from a prospective local database of infants with HIE.

RESULTS

Overall, 149 of 207 infants were included in the study: 112 exposed to TH and 37 not exposed. Cooled infants had a lower seizure burden overall (0.4 vs 2.3 min/h, P < 0.001) and were also less likely to be treated with ASM (74% vs 100%, P < 0.001). In multivariable regression models, not exposed to TH, having a depressed aEEG background, and having higher Apgar scores were associated with higher seizure burden (incidence rate ratio: 4.78 for noncooled infants, P < 0.001); also, not exposed to TH was associated with a higher likelihood of multidrug ASM (odds ratio: 4.83, P < 0.001).

CONCLUSIONS

TH in infants with moderate to severe HIE is associated with significant reduction of seizure burden and ASM therapy.

Prolonged Background Suppression Induced by Anticonvulsants Misleading Amplitude-Integrated Encephalography's Interpretation: A Single Case Report

Prognostic role of the amplitude-integrated encephalography (aEEG) is undeniable, but few works focused on the contribution of medications in misleading its interpretation. We report the case of an asphyxiated newborn enrolled for therapeutic hypothermia (TH) that required the simultaneous use of three anticonvulsants, whose administration resulted in a comatose state and in a switch to a flat trace on the aEEG. The prolonged flat trace on the aEEG, pointing toward a state of irreversible brain damage, led to early stop of TH to prevent therapeutic obstinacy; unexpectedly, once Midazolam was weaned off, the aEEG recovered to a discontinuous pattern. The case emphasizes the aEEG's noninfallibility and advises clinicians to consider the potential misleading effects of depressant medications on its interpretation in asphyxiated newborns undergoing TH.

Association between anti-seizure medication and outcomes in infants

OBJECTIVE

To compare treatment failure between: (1) infants treated with phenobarbital versus levetiracetam for first-line treatment and (2) infants treated with phenytoin versus levetiracetam for second-line treatment following phenobarbital.

STUDY DESIGN

This retrospective cohort study included infants with seizures receiving phenobarbital or levetiracetam as the initial anti-seizure medication. Treatment failure was defined as the need for additional anti-seizure medication within 24-72 h and compared using mixed-effect logistic regression after adjustment for confounding factors, including center.

RESULTS

In this cohort of 6842 infants, the incidence of treatment failure was 31% vs. 38% in infants receiving first-line phenobarbital versus levetiracetam (adjusted OR: 0.70; 95% CI 0.58-0.84). There was no significant difference in second-line treatment failure (adjusted OR: 1.31; 95% CI 0.92-1.86).

CONCLUSIONS

First-line treatment of neonatal seizures with phenobarbital is associated with a lower rate of treatment failure than levetiracetam. There was no significant difference in second-line treatment failure.

High-frequency oscillations recorded with surface EEG in neonates with seizures

OBJECTIVE

Neonatal seizures are often the first symptom of perinatal brain injury. High-frequency oscillations (HFOs) are promising new biomarkers for epileptogenic tissue and can be found in intracranial and surface EEG. To date, we cannot reliably predict which neonates with seizures will develop childhood epilepsy. We questioned whether epileptic HFOs can be generated by the neonatal brain and potentially predict epilepsy.

METHODS

We selected 24 surface EEGs sampled at 2048 Hz with 175 seizures from 16 neonates and visually reviewed them for HFOs. Interictal epochs were also reviewed.

RESULTS

We found HFOs in thirteen seizures (7%) from four neonates (25%). 5025 ictal ripples (rate 10 to 1311/min; mean frequency 135 Hz; mean duration 66 ms) and 1427 fast ripples (rate 8 to 356/min; mean frequency 298 Hz; mean duration 25 ms) were marked. Two neonates (13%) showed interictal HFOs (285 ripples and 25 fast ripples). Almost all HFOs co-occurred with sharp transients. We could not find a relationship between neonatal HFOs and outcome yet.

CONCLUSIONS

Neonatal HFOs co-occur with ictal and interictal sharp transients.

SIGNIFICANCE

The neonatal brain can generate epileptic ripples and fast ripples, particularly during seizures, though their occurrence is not common and potential clinical value not evident yet.

Effect of morphine on cerebral activity of extremely premature infants

BACKGROUND

Morphine is widely used for sedation in premature infants and may have long-term effects on neurodevelopmental outcome.

AIMS

To assess its effect on cerebral activity of extremely preterm infants.

METHODS

Retrospective study in infants less than 28 weeks of gestational age (GA), treated with morphine and monitored with amplitude integrated EEG (aEEG), that were assessed at baseline and 6 consecutive 2 h periods. At each period, the background activity score and presence of cycling were determined.

RESULTS

A total of 140 infants were included. Background aEEG activity score worsened in 40% of the infants by 6 h after morphine initiation and cycling, initially present in 70% of the infants, could be detected in only 10% after 10 h. On multivariable analysis, adjusted for baseline aEEG score and GA, the background activity decreased by 0.85 (95% confidence interval (CI): 0.74-0.97) immediately after morphine initiation, 0.72 (CI: 0.63-0.83) at 2 h later and on average by 0.64 (CI: 0.57-0.71) at each subsequent 2 h periods. The relative risk of cycling loss at 2 h and 4 h after morphine administration was 1.58 (CI: 1.15-2.16) and 3.37 (CI: 2.23-5.08), respectively.

CONCLUSIONS

Continuous infusion of morphine in extremely preterm infants significantly depresses their cerebral activity soon after its commencement.

Effect of Phenobarbitone on Amplitude-Integrated Electroencephalography in Neonates with Hypoxic-Ischemic Encephalopathy during Hypothermia

BACKGROUND

Phenobarbitone induces suppression of cerebral electrical activity on amplitude-integrated electroencephalography (aEEG) in neonates with hypoxic-ischemic encephalopathy (HIE); however, its effect during therapeutic hypothermia (TH) has not been well characterized.

OBJECTIVE

To evaluate the effect of phenobarbitone on aEEG in neonates with HIE undergoing TH.

METHODS

Thirty-five neonates born at ≥350 weeks gestational age (GA), who received phenobarbitone as first-line antiepileptic drug during TH for ≥ Sarnat stage II HIE with aEEG recordings were retrospectively studied. Background pattern, upper and lower margin voltages were characterized for a 30-min period before and 30-60 min after phenobarbitone administration. Primary outcome was presence of severely abnormal aEEG pattern after phenobarbitone administration.

RESULTS

Mean (±SD) GA and median birth weight were 38.2 ± 1.9 weeks and 3.1 (2.5-3.9) kg, respectively. Phenobarbitone (10-20 mg/kg), administered at median age 16.8 h, was associated with background pattern worsening in 19/29 (65.5%) cases. Severe background patterns were more prevalent in post- versus pre-phenobarbitone tracings (21/29 [72%] vs. 11/29 [38%]; p = 0.01). Presence of severe pattern versus either continuous normal voltage or discontinuous normal voltage pattern post-phenobarbitone, (20/25 [80%] vs. 3/8 [38%]; p = 0.036) was associated with death or moderate-to-severe injury on MRI brain. Median time to trace recovery, when measurable, was 4 h (45 min-72 h).

CONCLUSIONS

Phenobarbitone induces significant suppression on aEEG in infants with HIE undergoing TH. Development of severe aEEG background patterns after phenobarbitone may unmask a population at greater risk of abnormal outcome.

Diagnosis of seizures and encephalopathy using conventional EEG and amplitude integrated EEG

Seizures are more common in the neonatal period than at any other time of life, partly due to the relative hyperexcitability of the neonatal brain. Brain monitoring of sick neonates in the NICU using either conventional electroencephalography or amplitude integrated EEG is essential to accurately detect seizures. Treatment of seizures is important, as evidence increasingly indicates that seizures damage the brain in addition to that caused by the underlying etiology. Prompt treatment has been shown to reduce seizure burden with the potential to ameliorate seizure-mediated damage. Neonatal encephalopathy most commonly caused by a hypoxia-ischemia results in an alteration of mental status and problems such as seizures, hypotonia, apnea, and feeding difficulties. Confirmation of encephalopathy with EEG monitoring can act as an important adjunct to other investigations and the clinical examination, particularly when considering treatment strategies such as therapeutic hypothermia. Brain monitoring also provides useful early prognostic indicators to clinicians. Recent use of machine learning in algorithms to continuously monitor the neonatal EEG, detect seizures, and grade encephalopathy offers the exciting prospect of real-time decision support in the NICU in the very near future.

Treatment Effects on Neonatal EEG

Conventional EEG and amplitude-integrated electroencephalography are used in neonates to assess prognosis and significant changes in brain activity. Neuroactive medications and hypothermia can influence brain activity and therefore alter EEG interpretation. There are limited studies on the effect of these therapies on neonatal EEG background activity. Medication effects on the EEG or amplitude-integrated electroencephalography include increased interburst interval duration, voltage suppression, and sleep disruption. The effect is transient in term newborns but can be persistent in premature newborns. Although therapeutic hypothermia does not produce significant changes in EEG activity, it does change the time point at which EEG can accurately predict neurodevelopmental outcome. It is important to account for these effects on the EEG to avoid inaccurate interpretation that may affect prognostication.

Hemodynamic response to burst-suppressed and discontinuous electroencephalography activity in infants with hypoxic ischemic encephalopathy

Burst suppression (BS) is an electroencephalographic state associated with a profound inactivation of the brain. BS and pathological discontinuous electroencephalography (EEG) are often observed in term-age infants with neurological injury and can be indicative of a poor outcome and lifelong disability. Little is known about the neurophysiological mechanisms of BS or how the condition relates to the functional state of the neonatal brain. We used simultaneous EEG and diffuse optical tomography (DOT) to investigate whether bursts of EEG activity in infants with hypoxic ischemic encephalopathy are associated with an observable cerebral hemodynamic response. We were able to identify significant changes in concentration of both oxy and deoxyhemoglobin that are temporally correlated with EEG bursts and present a relatively consistent morphology across six infants. Furthermore, DOT reveals patient-specific spatial distributions of this hemodynamic response that may be indicative of a complex pattern of cortical activation underlying discontinuous EEG activity that is not readily apparent in scalp EEG.

Prognostic value of the recovery time of continuous normal voltage in amplitude-integrated electroencephalography in out-of-hospital cardiac arrest patients treated with therapeutic hypothermia: a retrospective study

BACKGROUND

The early prediction of neurological outcomes in postcardiac arrest patients treated with therapeutic hypothermia (TH) remains challenging. Amplitude-integrated electroencephalography (aEEG) is a type of quantitative EEG. A particular cutoff time from the return of spontaneous circulation (ROSC) to the recovery of a normal aEEG trace for predicting a good neurological outcome has not yet been established. The purpose of the present study was to examine the relation between neurological outcomes and the continuous normal voltage (CNV) recovery time in adult comatose survivors of cardiac arrest treated with TH and identify the recovery time cutoff for predicting a good neurological outcome.

METHODS

We retrospectively evaluated adult survivors of cardiac arrest with initial shockable rhythm treated with TH and monitored with aEEG. A good outcome was defined as a cerebral performance category (CPC) of 1 or 2 at hospital discharge. A CNV trace was considered as the normal aEEG trace, and the CNV recovery time was defined as the time from ROSC to the initial CNV trace.

RESULTS

The study included 30 patients, and of these patients, 22 had recovery of CNV trace. The median CNV recovery time was shorter among patients with a good outcome than that among those with a poor outcome (10.7 h [interquartile range (IQR), 7.4-15.8 h] vs. 28.6 h [IQR, 26.9-29.3 h]; p = 0.003). The area under the receiver operating characteristic curve of the CNV recovery time for predicting a good neurological outcome was 0.95 (95 % CI 0.86-1; p = 0.003), and the optimal cutoff was 23 h. The recovery of CNV trace within 23 h had a sensitivity of 89 %, specificity of 100 %, positive predictive value of 100 %, and negative predictive value of 86 % for predicting a good neurological outcome in all the patients, including the eight patients without recovery of CNV trace.

CONCLUSIONS

A CNV recovery time cutoff of 23 h might help predict a good neurological outcome in adult survivors of cardiac arrest treated with TH.

Treating disorders of the neonatal central nervous system: pharmacokinetic and pharmacodynamic considerations with a focus on antiepileptics

A major consideration in the treatment of neonatal disorders is that the selected drug, dose and dosage frequency is safe, effective and appropriate for the intended patient population. Thus, a thorough knowledge of the pharmacokinetics and pharmacodynamics of the chosen drug within the patient population is essential. In paediatric and neonatal populations two additional challenges can often complicate drug treatment - the inherently greater physiological variability, and a lack of robust clinical evidence of therapeutic range. There has traditionally been an overreliance in paediatric medicine on extrapolating doses from adult values by adjusting for bodyweight or body surface area, but many other sources of variability exist which complicate the choice of dose in neonates. The lack of reliable drug dosage data in neonates has been highlighted by regulatory authorities, as only ~50% of the most commonly used paediatric medicines have been examined in a paediatric population. Moreover, there is a paucity of information on the pharmacokinetic parameters which affect drug concentrations in different body tissues, and pharmacodynamic responses to drugs in the neonate. Thus, in the present review, we draw attention to the main pharmacokinetic factors that influence the unbound brain concentration of neuroactive drugs. Moreover, the pharmacodynamic differences between neonates and adults that affect the activity of centrally-acting therapeutic agents are briefly examined, with a particular emphasis on antiepileptic drugs.

Quantification of neonatal amplitude-integrated EEG patterns

BACKGROUND

Amplitude-integrated EEG (aEEG) is increasingly used in research with premature infants; however, comprehensive interpretation is limited by the lack of simple approaches for reliably quantifying and summarizing the data.

AIM

Explore operational measures for quantifying continuity and discontinuity, measured by aEEG as components of infant brain function.

STUDY DESIGN

An exploratory naturalistic study of neonates while in the Neonatal Intensive Care Unit (NICU). One single channel aEEG recording per infant was obtained without disruption of nursing care practices.

SUBJECTS

24 infants with mean postmenstrual age (PMA) of 33.11 weeks (SD 3.49), average age of 2.62 weeks (SD 1.35) and mean birth weights of 1.39 kg (SD 0.73).

OUTCOME MEASURES

Quantification of continuity and discontinuity included bandwidth and lower border of aEEG, calculated proportion of time with signal amplitude below 10 μV, and peak counts. Variance of bandwidth and lower border denoted cycling.

RESULTS

Group mean bandwidth was 52.98 μV (SD 27.62). Median peak count in 60 second epochs averaged 3.63 (SD 1.74), while median proportion < 10 μV was 22% (SD 0.20). The group mean of lower border within-subject aggregated medians was 6.20 μV (SD 2.13). Group mean lower border standard deviation was 3.96 μV. Proportion < 10 μV showed a strong negative correlation with the natural log of the lower border median (r = -0.906, p < .0001) after controlling for PMA.

CONCLUSIONS

This study introduces a novel quantification process by counting peaks and proportion of time < 10 μV. Expanded definitions and analytic techniques will serve to strengthen the application of existing scoring systems for use in naturalistic research settings and clinical practice.

Premedication for intubation with morphine causes prolonged depression of electrocortical background activity in preterm infants

BACKGROUND

Sedative and analgesic medications are used in critically ill newborns, but little is known about their effects on electrocortical activity in preterm infants. We hypothesized that morphine might induce prolonged neurodepression, independent of blood pressure, as compared with rapid sequence induction/intubation(RSI).

METHODS

Of 34 infants enrolled in a randomized controlled trial (RCT) comparing RSI (including thiopental 2-3 mg/kg and remifentantil 1 mcg/kg) with morphine (0.3 mg/kg) as premedication for intubation, 28 infants (n = 14 + 14; median gestational age 26.1 wk and postnatal age 138 h) had continuous two-channel amplitude-integrated electroencephalogram (aEEG/EEG) and blood pressure monitoring during 24 h after the intubation. Thirteen infants not receiving any additional medication constituted the primary study group. Visual and quantitative analyses of aEEG/EEG and blood pressure were performed in 3-h epochs.

RESULTS

RSI was associated with aEEG/EEG depression lasting <3 h. Morphine premedication resulted in aEEG/EEG depression with more discontinuous background and less developed cyclicity for 24 h, and during the first 9 h, interburst intervals (IBI) were significantly increased as compared with those of RSI treatment. The difference was not related to blood pressure.

CONCLUSION

Premedication with morphine is associated with prolonged aEEG/EEG depression independent of blood pressure changes and may not be optimal for short procedures.

Early predictors of short term neurodevelopmental outcome in asphyxiated cooled infants. A combined brain amplitude integrated electroencephalography and near infrared spectroscopy study

BACKGROUND

Brain Cooling (BC) represents the elective treatment in asphyxiated newborns. Amplitude Integrated Electroencephalography (aEEG) and Near Infrared Spectroscopy (NIRS) monitoring may help to evaluate changes in cerebral electrical activity and cerebral hemodynamics during hypothermia.

OBJECTIVES

To evaluate the prognostic value of aEEG time course and NIRS data in asphyxiated cooled infants.

METHODS

Twelve term neonates admitted to our NICU with moderate-severe Hypoxic-Ischemic Encephalopathy (HIE) underwent selective BC. aEEG and NIRS monitoring were started as soon as possible and maintained during the whole hypothermic treatment. Follow-up was scheduled at regular intervals; adverse outcome was defined as death, cerebral palsy (CP) or global quotient <88.7 at Griffiths' Scale.

RESULTS

2/12 Infants died, 2 developed CP, 1 was normal at 6 months of age and then lost at follow-up and 7 showed a normal outcome at least at 1 year of age. The aEEG background pattern at 24 h of life was abnormal in 10 newborns; only 4 of them developed an adverse outcome, whereas the 2 infants with a normal aEEG developed normally. In infants with adverse outcome NIRS showed a higher Tissue Oxygenation Index (TOI) than those with normal outcome (80.0±10.5% vs 66.9±7.0%, p=0.057; 79.7±9.4% vs 67.1±7.9%, p=0.034; 80.2±8.8% vs 71.6±5.9%, p=0.069 at 6, 12 and 24 h of life, respectively).

CONCLUSIONS

The aEEG background pattern at 24h of life loses its positive predictive value after BC implementation; TOI could be useful to predict early on infants that may benefit from other innovative therapies.

Intramuscular dexmedetomidine: an effective route of sedation preserves background activity for pediatric electroencephalograms

OBJECTIVES

To describe the efficacy and outcome of dexmedetomidine (Dex) via the intramuscular (IM) route for sedation for electroencephalography (EEG).

STUDY DESIGN

Quality assurance data and EEG studies were reviewed for consecutive patients who received IM Dex for EEGs between August 2007 and September 2009. Sleep spindles, delta waves, and beta activity were evaluated to determine the deepest stage of sleep achieved.

RESULTS

One hundred seven consecutive children (age 0.2-17 years) between August 2007 and September 2009 received IM Dex (range 1.0-4.5 mcg/kg). The average time to achieve sedation was 15.5 minutes (range 3.0-55.0) with an average of 54.5 minutes to meet discharge criteria following EEG studies, which averaged 34.2 ± 22.6 minutes. The deepest stage of sleep recorded for each child was: awake (n = 1), stage N2 (n = 51), and stage N3 (n = 55). Excessive beta activity was seen in only 1 patient. Epileptiform activity was noted in 11 patients. Hemodynamic fluctuations in heart rate and blood pressure were noted, none of which required pharmacologic intervention. All EEGs were successfully completed.

CONCLUSION

We describe Stage 3 sleep and preserved background activity in response to Dex. We present the IM route as a new method, which preserves background EEG activity to provide safe and effective sedation for EEG studies.

Effects of midazolam and lidocaine on spectral properties of the EEG in full-term neonates with stroke

Assessment of the neonatal EEG may be hampered by drug-specific changes in electrocortical activity. To quantify effects of a loading dose of midazolam and lidocaine on the EEG frequency spectrum of full-term neonates with perinatal arterial ischemic stroke (PAIS), 11 full-term infants underwent multi-channel amplitude-integrated EEG (aEEG) and EEG recordings. During recording, midazolam and/or lidocaine were administered as anti-epileptic drug. Retrospectively, we performed spectral analysis on 4-h EEG segments around the loading dose. The frequency spectrum was divided in δ (1-4 Hz), θ (4-8 Hz), α (8-13 Hz) and β (13-30 Hz) bands. Midazolam induced immediate suppression of the aEEG background pattern for 30-60 min. Spectral EEG analysis showed decreased total and absolute frequency band powers. Relative δ power decreased, θ power increased while α and β powers remained constant. Lidocaine induced no aEEG background pattern suppression. Total and absolute EEG band powers were unchanged. Relative δ power decreased, θ and α power increased and β power remained constant. Effects of lidocaine were more pronounced in the stroke-affected hemisphere. In conclusions, both drugs induced a shift from low to higher frequency electrocortical activity. Additionally, midazolam reduced total EEG power. These spectral changes differ from those seen in adult studies.

Influence of respiratory acidosis and blood glucose on cerebral activity of premature infants

Fluctuations of physiologic parameters in extremely preterm infants may significantly affect their cerebral activity. This study assessed the correlation between blood gas indices and other clinical parameters with cerebral activity, as recorded by amplitude integrated electroencephalography in the first three days of life of a prospective cohort study of infants born at <28 weeks gestation. Amplitude integrated electroencephalography was assessed according to a nine-grade pattern scale. For univariate analysis, the Spearman rank coefficient, Student t test, and χ(2) test were used. For multivariate analysis, generalized estimating equations were used. Overall, 255 blood samples from 24 recruited infants were analyzed. The pattern scale demonstrated a significant positive correlation with pH (ρ = 0.45, P < 0.0001) and base excess (ρ = 0.37, P < 0.0001), and a significant negative correlation with partial pressure of carbon dioxide (pCO(2)) (ρ = -0.35, P < 0.0001) and blood dextrose (ρ = -0.36, P < 0.0001). When amplitude integrated electroencephalography was used as dependent variable, the best generalized estimating equation models yielded significant correlations for pH, pCO(2), and HCO(3)(-). When pH was used as dependent variable, the best models yielded significant correlations for amplitude integrated electroencephalography pattern scale and blood dextrose. We suggest that depression in cerebral function early in life should prompt clinicians to assess acid/base status and respiratory parameters of the extremely premature infant as well as other known causes of cerebral depression.

Effects of morphine and midazolam on sleep-wake cycling in amplitude-integrated electroencephalography in post-surgical neonates ≥ 32 weeks of gestational age

BACKGROUND

Studies of children who undergo major non-cardiac surgery in the neonatal period are needed so that subsequent abnormal neurodevelopment can be better understood.

OBJECTIVE

It was the aim of our study to describe the influence of analgesic and sedative medication on the predominant background pattern and the development of sleep-wake cycling (SWC), as measured on amplitude-integrated electroencephalography (aEEG), in newborn infants born ≥ 32 weeks' gestation after major non-cardiac surgery.

METHODS

This prospective study included infants ≥ 32(+0) weeks' gestation admitted to the Neonatal Intensive Care Unit at The Royal Children's Hospital in Melbourne who were undergoing major non-cardiac surgery. Data on morphine and midazolam given after surgery were recorded and the BrainZ Monitor was applied post-operatively. The maximum levels of morphine and midazolam were assessed as predictors of time to aEEG outcomes using linear regression.

RESULTS

Forty-seven eligible infants were included. Emergence of SWC was observed at a mean of 13 h after surgery. The maximum dose of morphine or midazolam was not predictive of time to either any or developed SWC.

CONCLUSIONS

Despite high doses of morphine and midazolam, SWC was observed on aEEG in neonates ≥ 32 weeks' gestational age soon after major non-cardiac surgery. The aEEG background pattern was not affected by the maximum dose of either morphine or midazolam.

Rapid sequence induction is superior to morphine for intubation of preterm infants: a randomized controlled trial

OBJECTIVES

To compare rapid sequence intubation (RSI) premedication with morphine for intubation of preterm infants.

STUDY DESIGN

Preterm infants needing semi-urgent intubation were enrolled to either RSI (glycopyrrolate, thiopental, suxamethonium, and remifentanil, n = 17) or atropine and morphine (n = 17) in a randomized trial. The main outcome was "good intubation conditions" (score ≤10 assessed with intubation scoring), and secondary outcomes were procedural duration, physiological and biochemical variables, amplitude-integrated electroencephalogram, and pain scores.

RESULTS

Infants receiving RSI had superior intubation conditions (16/17 versus 1/17, P < .001), the median (IQR) intubation score was 5 (5-6) compared with 12 (10.0-13.5, P < .001), and a shorter procedure duration of 45 seconds (35-154) compared with 97 seconds (49-365, P = .031). The morphine group had prolonged heart rate decrease (area under the curve, P < .009) and mean arterial blood pressure increase (area under the curve, P < .005 and %change: mean ± SD 21% ± 23% versus -2% ± 22%, P < .007) during the intubation, and a subsequent lower mean arterial blood pressure 3 hours after the intubation compared with baseline (P = .033), concomitant with neurophysiologic depression (P < .001) for 6 hours after. Plasma cortisol and stress/pain scores were similar.

CONCLUSION

RSI with the drugs used can be implemented as medication for semi-urgent intubation in preterm infants. Because of circulatory changes and neurophysiological depression found during and after the intubation in infants given morphine, premedication with morphine should be avoided.

Delayed onset of sleep-wake cycling with favorable outcome in hypothermic-treated neonates with encephalopathy

OBJECTIVE

To determine whether hypothermia modulates acquisition of sleep-wake cycling in term neonates with moderate to severe hypoxic-ischemic encephalopathy (HIE) and the relationship to outcome.

STUDY DESIGN

Twenty-nine term infants with moderate to severe HIE treated with selective head cooling were evaluated. All were monitored with amplitude-integrated electroencephalography during and video electroencephalography immediately after hypothermia for ≥72 hours. Electroencephalograpic data were analyzed for background and sleep-wake cycling. Abnormal outcome included death or severe global neurodevelopmental disability ≥18 months.

RESULTS

Acquisition of sleep-wake cycling was noted in nine infants by 72 hours, in 13 by 96 hours, 19 by 120 hours, and 22 by 144 hours. Presence of sleep-wake cycling was associated with normal outcome, that is, 14 of 22 (64%), versus abnormal outcome, that is, none of seven without sleep-wake cycling (P = .006). The presence of sleep-wake cycling by 120 hours had a positive predictive value of 68% and negative predictive value of 90%. Magnetic resonance imaging abnormalities were related to onset of sleep-wake cycling.

CONCLUSIONS

Although onset of sleep-wake cycling is markedly delayed in term neonates with moderate to severe HIE treated with hypothermia, approximately 65% with acquisition of cycling have a normal outcome. Sleep-wake cycling is an important additional tool for assessing recovery in term infants with moderate to severe HIE treated with hypothermia.

The use of conventional EEG for the assessment of hypoxic ischaemic encephalopathy in the newborn: a review

Neonatal hypoxic ischaemic encephalopathy continues to be one of the leading causes of morbidity and mortality among neonates around the globe. With the advent of therapeutic hypothermia, the need to accurately classify the severity of injury in the early neonatal period is of great importance. As clinical measures cannot always accurately estimate the severity early enough for treatment to be initiated, clinicians have become more dependent on conventional and amplitude integrated EEG. Despite this, there is currently no single agreed classification scheme for the neonatal EEG in hypoxic ischaemic encephalopathy. In this review we discuss classification schemes of neonatal background EEG, published over the past 35 years, highlighting the urgent need for a universal visual analysis scheme.

Neonatal electroencephalography: review of a practical approach

Neonatal electroencephalography (EEG) recordings have routinely been performed for more than half a century. ''Old'' technical difficulties are no longer of concern with the advent of modern digital technology. Still, many ''old'' issues are at debate: characterization of neonatal EEG features, identification of EEG waveforms with potential clinical correlates, the role of neonatal EEG in prediction of neurodevelopmental outcome, and use of new devices. In the past decades, neonatal EEG and emerging issues' literature has greatly expanded. In this review, the authors have summarized some of these issues to increase the availability of the information for both clinical and research purposes. They propose an up-to-date concentrated practical approach to this rapidly expanding ''subfield'' of neonatal neurology.