Cerebral Monitoring of the Term Infant

Transcription

1 Cerebral Monitoring of the Term Infant Shelly V. Lavery, RN, BaHSc Kathi S. Randall, RN, MSN, CNS, NNP-BC Cerebral injury can have devastating consequences for long-term neurologic development. In some countries, limited-channel continuous bedside cerebral monitoring of infants at risk of cerebral injury has become part of routine clinical care in the NICU. 1 Most NICUs in the U.S. do not yet routinely monitor brain function continuously at the bedside. New technologies are changing this practice and can provide the ability to gain further insights into brain function beginning upon admission. In most NICUs, sick infants who have suffered a hypoxicischemic event are monitored from the moment of birth using invasive and noninvasive devices. It is not uncommon to quickly apply one or two oxygen saturation probes, three electrocardiogram (ECG) leads, a temperature probe, and a blood pressure cuff on an arm or leg. Often umbilical lines are inserted and attached to blood pressure transducers, and flow detectors are secured to ventilator circuits and endotracheal tubes. These devices have become so routine that many NICU nurses believe they could not adequately provide care without them. But often there is no continuous bedside monitoring of the organ most at risk of injury the brain. In this article, we review the evidence for current clinical uses of continuous bedside brain monitors in the NICU. We also describe the nurse s role in applying and using these Accepted for publication January Revised April Abs t r a c t Continuously monitoring brain function at the bedside in the NICU for term infants at risk of brain injury has become part of routine clinical practice in many countries. These monitors offer invaluable information about the sick infant s neurologic status by providing real-time measurements of the brain s electrical activity and identifying or confirming seizure activity. With the increasing availability of bedside electroencephalogram technology, it is essential for neonatal intensive care nursing staff to understand the rationale for its use, as well as the fundamentals of application and interpretation of this new technology. monitors. And an introduction to the interpretation of the more common patterns seen on these tools will assist the bedside nurse to appropriately refer abnormal brain activity for further evaluation. Conventional EEG The conventional electroencephalographic (ceeg) signal at the scalp represents the sum of the excitatory and inhibitory postsynaptic potentials from the neurons in the cerebral cortex. This creates small electrical impulses that can be measured by placing surface electrodes on the scalp. The ceeg displays a magnified raw/unprocessed waveform that correlates with the electrical impulses. In the presence of hypoxic or ischemic brain injury, there is reduced or abnormal cortical electrical activity. ceeg is most commonly used to measure the impact of a neurologic insult on the brain and to detect the presence of seizure activity. ceeg sensors are applied by specialized technicians using sensors, creating multiple channels between the sensors where the electrical activity can be measured. 2 In the acute clinical setting, ceeg is usually recorded for minutes by the EEG technician, this is sometimes known as a multichannel EEG tracing. Funding and salary support have been contributed by BrainZ Instruments (New Zealand). VOL. 27, NO. 5, September/october

2 FIGURE 1 n Neonate with bedside brain monitoring. real-time interpretation of the level of electrical activity of the brain at the bedside and visualization of changes in brain activity over extended periods of time. Today a number of bedside cerebral monitoring tools incorporate aeeg (Figure 1). Historically, these bedside aeeg monitors used a single biparietal channel (two sensors). The newer aeeg monitors use two channels (four sensors) in the parietal and central positions. The simplicity of these monitors allows them to be maintained by the bedside nurse and used as clinically required. The need for continuous brain monitoring Courtesy of Royal Children s Hospital, Melbourne, Australia. When neurologists analyze the output from a multichannel EEG tracing, they consider the individual morphology, frequency, amplitude, and evolution of the waveforms in relation to multiple channels. This information may assist in identifying abnormal levels of cortical electrical brain activity generally or focally, the existence of potentially epileptogenic foci, or ongoing seizures. The ceeg also assists in determining brain maturation, sleep state development, and the presence of artifact. Although it represents a short period of time, the ceeg provides comprehensive and subtle information about the whole cerebral cortex. However, the process of ordering a ceeg, arranging for a specialized technician to apply the EEG, and having a neurologist review and report on the ceeg may involve considerable delay. Amplitude Integrated EEG Amplitude integrated EEG (aeeg) was developed in the late 1960s to continuously monitor adult patients during anesthesia and in intensive care. The aeeg measures, filters, and time-compresses the raw EEG signal to create a simplified pattern that is easy to interpret. 3 This pattern permits Hypoxic-ischemic Encephalopathy Hypoxic-ischemic encephalopathy (HIE), affects 1 6 per 1,000 live births. 4 HIE can result in alterations of cerebral metabolism and reduction or derangement of cerebral electrical activity. Currently, the neurologic evaluation of encephalopathic infants relies heavily on clinical examination, which can be altered by the administration of sedatives, muscle relaxants, and antiepileptic drugs (AEDs). Other evaluation methods include multichannel EEG, cranial ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI). Each of these offers a detailed static snapshot of the newborn brain, but they also require skill in application and interpretation. Additionally, transporting sick infants away from the unit to complete these neurologic examinations poses logistical challenges and inherent risks. With the promise of therapeutic interventions to improve the outcome from cerebral injury, the need is increasing for early bedside neurologic evaluation in the term encephalopathic infant. In term infants, aeeg has been shown to be very reliable in evaluating brain function after hypoxic-ischemic events. Studies have shown that patterns on aeeg have a high concordance with conventional 16-lead neonatal EEG 5,6 and MRI. 7 Other studies have demonstrated that aeeg patterns recorded in the first three to six hours of life are predictive of later neurodevelopmental outcomes in term encephalopathic infants. 8,9 A study by Eken and colleagues recruited 34 term infants with HIE within six hours of delivery. Bedside neurologic evaluations included cranial ultrasonography, Doppler ultrasonography, somatosensory evoked potentials, visual evoked potentials, and a single-channel aeeg brain monitor. These infants were followed up at 3, 9, 18, and 24 months of age. The aeeg monitor had the highest positive predictive value (PPV), 84.2 percent, and the highest negative predictive value (NPV), 91.7 percent, for an abnormal neurodevelopmental outcome (developmental quotient below 85 on the Griffths scale or cerebral palsy). Of the 12 infants with a normal aeeg pattern, all but 1 had a good outcome. 8 Toet and coworkers studied a larger cohort of 73 term infants treated for perinatal asphyxia, of which 68 were followed up for more than 12 months (range 12 months to six years). The 330 September/october 2008, VOL. 27, NO. 5

3 FIGURE 2 n aeeg of infant with unilateral cerebral injury. Note abnormal reduction of waveform activity on the EEG right channel, reflected in the aeeg right channel (lower band). FIGURE 3 n Normal aeeg, with lower margin predominantly above 5 microvolts and upper margin above 10 microvolts. Sleep/wake cycling wide part of band represents quiet sleep, and narrow part of band represents active sleep/awake. single-channel aeeg was classified at three and six hours of age. The PPV was 78 percent, and NPV was 84 percent three hours after birth. At six hours, the PPV was 86 percent, and the NPV was 91 percent. 9 Based on these predictive capabilities, abnormalities on aeeg recordings were used as a selection criterion for entry into published and ongoing large randomized hypothermia trials and may be utilized alongside future neuroprotective strategies. 10,11 Further prognostic information can be derived from the evolution of or recovery from cerebral injury. One study reviewed the aeegs of 160 term infants with signs of perinatal asphyxia and concluded that if a severely abnormal aeeg pattern returns to normal within 24 hours of life, an infant has a 61 percent chance of surviving with mild or no disability. 12 If the aeeg remains severely abnormal after 48 hours of life, the long-term prognosis is very poor. 13 Cerebral assessment by aeeg, in conjunction with a neurologic clinical examination, has been demonstrated to yield a higher PPV of short-term outcome than clinical assessments alone. 14 Thus, aeeg promises to improve the accuracy of identifying at-risk infants who can benefit from timely therapeutic intervention while reducing unnecessary treatment of infants not at risk. Neonatal cerebral infarction, or stroke, may present in an otherwise healthy infant with subtle neurologic abnormalities such as poor feeding skills or clinical seizures. Cerebral infarctions have historically been underdiagnosed or diagnosed late. However, with neuroimaging becoming more accessible to the neonatal population, the diagnosis of perinatal and neonatal stroke is becoming more common. 15 Cerebral infarction accounts for as much as 20 percent of cerebral injury in the term infant with encephalopathy. 16,17 Thrombolytic and rehabilitation therapies have been developed for neonates with stroke-like lesions and may improve outcomes. 18,19 These interventions may require early recognition and diagnosis for greatest effectiveness. At the very least, early diagnosis would allow at-risk infants to be eligible to receive timely early intervention and rehabilitation service. The newer aeeg brain monitor tools offer two or more channels to allow for comparison of electrical activity between cerebral hemispheres, helping to identify unilateral or focal injury (Figure 2). 20 Although most studies have focused on infants with HIE, more recent studies are exploring the prognostic value of aeeg for other neurologic disorders, using similar aeeg classifications as the studies that have been previously described. One of these studies reported on 86 encephalopathic infants of varying etiologies including meningitis, metabolic disorders, and cerebral vascular infarction. The infants had aeeg monitoring in the first three days of life and an MRI within the primary admission. Despite the varying timing of monitoring and the differing diagnoses, a strong correlation was demonstrated between an abnormal aeeg and cerebral injury as shown on MRI. 7 There is also increasing interest in aeeg monitoring of other infants who are at risk of cerebral injury, for example infants undergoing extracorporeal membrane oxygenation, 21 and in ongoing trials monitoring neonates with congenital heart disease undergoing cardiopulmonary bypass (in Melbourne, Australia, and Auckland, New Zealand). 22 Sleep/wake cycling can be identified on the aeeg pattern (Figure 3). This capability may help the bedside clinician VOL. 27, NO. 5, September/october

4 Clinical Application of aeeg Bedside Monitors in the NICU Pot e n t i a l b e n e f i t s o f aeeg m o n i t o r i n g : Ba c k g r o u n d (le v e l o f b r a i n a c t i v i t y) Assist in prognosis of long-term outcome in the encephalopathic term infant Assist in appropriate timing of referral for further neurologic investigations Aid in selecting infants at risk of cerebral injury who may benefit from neuroprotective strategies Identify electrical symmetry between the cerebral hemispheres in babies at risk of cerebral injury to identify focal or unilateral cerebral injury for appropriate referral Identify presence or absence of sleep/ wake cycling Pot e n t i a l b e n e f i t s o f aeeg m o n i t o r i n g : Se i z u r e s Identify the presence of seizures to alert clinicians of cerebral dysfunction Identify subclinical seizures that would be undetectable without monitoring Aid pharmacologic management of seizures Differentiate abnormal movements that are not associated with electroencephalographic seizures recognize the sleep states of the neonate and may also have implications for developmental care and nursing research. 23 Clinically assessing sleep states of a sick infant can be extremely challenging, leaving many unanswered questions: How much sleep are sick infants getting in a busy NICU? What are the barriers to sleep? Could a monitoring tool that identifies sleep states assist nurses to choose the best timing for nursing care? Do developmental care practices affect the quality or quantity of sleep patterns in the NICU? Does protecting sleep optimize neurodevelopmental outcomes? A tool that objectively measures sleep, at the bedside, in the NICU can help answer many important research questions that may potentially influence day-to-day NICU care practices. 24 Seizures One of the main signs of cerebral dysfunction is seizure activity. 25 Depending on etiology, neonatal seizures are associated with high mortality and neurodevelopmental delay. 26,27 In addition, an animal study demonstrated that the experimental induction of repeated seizures with existing hypoxic-ischemic injury may exacerbate cerebral injury. 28 These results highlight the concern that unrecognized and untreated seizures may cause further injury in infants with an existing hypoxic-ischemic injury. Clinical assessment of seizures alone may be unreliable. 29 Neonatal seizures often have subtle signs, e.g. apnea, lip smacking, tongue thrusting, changes in heart rate or blood pressure, that make recognition of them challenging. Two video ceeg studies documented that more than 50 percent of neonatal seizures are subclinical (electrographic seizures with an absence of visible clinical signs). 30,31 Most commonly used anticonvulsant medications may be inadequate, effectively treating only 50 percent of seizures and often initiating electroclinical or electromechanical dissociation in which the clinical manifestation of a seizure ceases after treatment with AEDs but electrically the seizure continues. 32,33 Bedside aeeg monitoring can be a useful tool in infants at risk of seizure activity by enhancing the ability to diagnose subclinical seizures and evaluating the electrical encephalographic response to antiepileptic therapy. 34 Bedside aeeg monitoring may also help to identify infants with abnormal movements that are not associated with electroencephalographic seizures. Boylan and colleagues evaluated 24 infants with ceeg monitoring where there was a clinical suspicion of neonatal seizures or high risk of developing seizures. Seven of these infants had clinical seizures with no corresponding seizure activity on ceeg. Of these 7 infants, 6 had a normal ceeg background and a normal MRI, and 5 were categorized with a normal outcome at one year of age. 30 Accurately identifying which abnormal movements are not seizure activity helps ensure that infants are not treated with AEDs unnecessarily. A study by Toet and colleagues published in 2005, demonstrated that treating all clinical and subclinical seizures identified by aeeg positively affected outcome. These investigators evaluated 206 term infants who were treated with AEDs for neonatal seizures that were detected by aeeg. They received AEDs for clinical as well as subclinical neonatal seizures. Eighty percent of the infants had a diagnosis of HIE, with the remaining diagnosed with intracranial hemorrhage or perinatal arterial stroke. 35 Follow-up data from five assessments (at 3, 9, and 15 months, and at three and five years) analyzed for their neuro developmental outcome and the presence of postneonatal epilepsy showed that the incidence of postnatal epilepsy was reduced to 9.4 percent. This is less than the percent incidence reported earlier in children who received treatment only for clinical 332 September/october 2008, VOL. 27, NO. 5

5 seizures. 36 Toet and colleagues study demonstrated how continuous bedside brain monitoring for seizure identification and treatment of clinical and subclinical seizures may improve an infant s outcome. In a busy NICU environment, subtle seizures may go unobserved. Most neonatal nurses have experienced the frustration of witnessing abnormal movements that are not repeated in the presence of medical personnel or during a ceeg recording. Long-term bedside brain monitoring can be a useful tool to increase accurate recognition of both clinical and subclinical seizures to identify cerebral dysfunction and prompt further investigation. It may also assist in evaluating the effect of therapies in the presence of electromechanical dissociation. Continuous brain monitoring can help the bedside nurse distinguish abnormal movements from seizure activity, ensuring that infants are not unnecessarily treated with AEDs (See: Clinical Application of aeeg Bedside Monitors in the NICU). Case Example Baby Jones is a 42-week infant, born by emergency cesarean birth for a presumed placental abruption. There was meconium-stained fluid present, and several prolonged late decelerations were recorded prior to delivery. He required resuscitation and mechanical ventilation, with Apgar scores of 1, 1, 3, 5, and 7 at 1, 5, 10, 15, and 20 minutes, respectively. He was admitted to the NICU on a Saturday night at 9 pm, pale, flaccid, tachycardic, and hypotensive. At midnight, you observe repetitive, rhythmic, clonic movements of both arms that do not stop on containment. These movements are noted several more times in the next hour; you page the neonatal nurse practitioner to the bedside. Baby Jones is given a 20 mg/kg loading dose of phenobarbital, and the seizurelike movements cease during the next hour. He will now be well sedated, which influences the results of any clinical examinations; yet subclinical seizures may still be occurring. Furthermore, the overall level of brain activity may contribute to determining his prognosis, which could assist with direction of treatment. Continuous aeeg brain monitoring could make this important information immediately available to the bedside clinicians caring for Baby Jones. Monitors can be applied at any time of the day or night, continued over long periods of time, and provide information immediately at the bedside. Bedside aeeg monitoring should be used in conjunction with other neurodiagnostic examinations whenever possible, such as MRI, CT, ultrasound, and ceeg; together they provide a comprehensive view of altered brain function and structure. Bedside brain monitors do not replace other technologies, but they do assist with early recognition of altered brain function, aid in the decision to pursue additional diagnostic tests, and give clinicians the ability to monitor the effectiveness of some interventions. To further illustrate this point, consider a comparison between brain monitoring and cardiac monitoring. When an infant on a cardiac monitor is noted to have an arrhythmia pattern, the medical team is notified and may order a 12-lead ECG, serum electrolytes, an echocardiogram, and even a cardiology consult to assist in the infant s management. Similarly, if abnormal brain activity is identified on the bedside brain monitor, the medical team may order further neurologic investigations to discover the cause and possibly order a consultation with a neurologist. Electrolytes and blood glucose levels may be reviewed, and a cranial ultrasound might be obtained to look for structural problems or intracranial bleeding. If CT and MRI are available, scans may be done to investigate brain structure and possible cerebral injury in greater detail. the Nurse s Role The nurse s role and responsibilities in regard to bedside brain monitoring are usually defined by individual NICU policies. However, application and maintenance of sensors, navigation of the monitor interface, and interpretation of the aeeg pattern are within the expertise of the NICU nurse. The nurse s role in documenting medication that affects the central nervous system is invaluable for optimal interpretation of the aeeg pattern. The nurse also needs to document any events that may cause a change in recording and possible identification of artifacts. As she must with any bedside monitoring system, the nurse needs to be aware of what is normal and abnormal for appropriate referral to the intensive care team. Application of Sensors The more opportunities that nurses have to apply the sensors, the quicker they will become skilled with the application. Most aeeg monitors use two to four soft hydrogel adhesive sensors (similar to ECG electrodes) that are applied to the scalp over each parietal and the central regions of the brain. These are noninvasive and are unlikely to cause irritation or pressure with prolonged use. However, the skin needs to be adequately prepared to ensure good contact. This involves cleaning, gentle abrasion with an exfoliant, and parting the hair to enable maximal scalp exposure to the gel sensors. Some NICUs may allow shaving of a small section of hair if contact remains problematic. Small, subdermal needle sensors are also available and are used routinely in some units. Needle sensors have the advantage of being quicker to apply, but they incur the potential problems of any invasive procedure. Once the sensors are applied, most brain monitors have a visual alarm to alert the bedside nurse that a sensor may need to be reapplied. Interpretation of aeeg in Term Infants Assessment of the aeeg tracing takes only a small amount of training and basic pattern recognition skills. NICU nurses are already extremely skilled at applying pattern recognition skills and observing for trends as they constantly review incoming data such as ECG information and ventilator loops. VOL. 27, NO. 5, September/october

6 Background/Brain Activity Care must be taken with interpretation in the presence of AEDs and sedation, which may depress the EEG signal and, in turn, the aeeg. Ideally, brain monitoring should be initiated on admission, providing a baseline before medication begins. It is important to document the administration of these medications so their effect on the aeeg will be evident. Visualization of the unprocessed/raw EEG signal assists in the identification of artifacts that may elevate the baseline, such as muscle artifact and extra waveforms caused by rapid ventilation. The aeeg is presented as a dense band charted on a semilogarithmic microvoltage scale (Figure 4). The position of this band reflects the amount of electrical brain activity; that is, the lower the brain activity, the lower the voltage reading, thus the lower the level of the band. This band is plotted over time on the x-axis. Various aeeg classifications have been described. 5,9,37,38 Perhaps the easiest for clinical application is based on the voltage levels of the lower and upper margins of the band (see Figure 4). 5 Normal Patterns The normal neonatal brain activity pattern with sleep/wake cycling present is called continuous. The lower margin of the dense band sits predominantly above 5 microvolts, and the upper margin of the band is above 10 microvolts. When the infant is in a quiet sleep, the band usually widens with the lower margin dropping. When the infant is in active sleep or awake, the activity becomes more continuous, and the band narrows with the lower margin rising (see Figure 3). In term infants, this is usually a 20-minute cyclical pattern. 39 Moderately Abnormal Pattern When there is a mixture of low activity and higher activity, the pattern is called discontinuous. It is displayed as a wide aeeg band due to the variable levels of brain activity and waveforms. The lower margin is variable, but is consistently less than 5 microvolts, reflecting the lower activity of the brain. The upper margin, as with the normal pattern, remains above 10 microvolts, representing the presence of some higher levels of activity (Figure 5). This pattern may be seen after the administration of anticonvulsant medications and after mild hypoxic events. 39 FIGURE 4 n Lower (yellow) and upper (red) margin of aeeg band. Severely Abnormal Patterns Burst suppression, continuous low voltage, and isoelectric or flat traces are all examples of severely abnormal aeeg patterns. Their common thread is that most of the brain activity is low, causing the aeeg lower margin to be consistently less than 5 microvolts and straight. As the brain becomes energy depleted, the top margin of the aeeg progresses toward values less than 10 microvolts (continuous low voltage) (Figure 6). 39 Burst suppression is classified as a severely abnormal pattern. The raw EEG is characterized by mostly suppressed activity with brief abnormal bursts of brain activity. The suppressed sections of the EEG give the aeeg pattern a straight and low bottom margin, but the brief bursts of high-amplitude waves create spikes on the aeeg greater than 25 microvolts (Figure 7). 37 Seizures Seizures are characterized by increasing brain activity. This causes a rise in the lower margin and usually the upper margin of the aeeg band, creating an arch in the aeeg record (Figure 8). 39 This feature enables the clinician to quickly scan for areas where the raw EEG signal should be Unprocessed/raw EEG (Left cerebral hemisphere) Unprocessed/raw EEG (Right cerebral hemisphere) aeeg (Left cerebral hemisphere) aeeg (Right cerebral hemisphere) FIGURE 5 n Moderately abnormal (discontinuous) aeeg with lower margin predominantly below 5 microvolts and upper margin above 10 microvolts. Lower margin is less than 5 µv Lower margin is less than 5 µv 334 September/october 2008, VOL. 27, NO. 5

7 FIGURE 6 n Severely abnormal (continuous low voltage) aeeg, with lower margin below 5 microvolts and upper margin below 10 microvolts. FIGURE 7 n Severely abnormal (burst suppression) aeeg with lower margin below 5 microvolts and high-voltage spikes greater than 25 microvolts. Upper margin is less than 10 µv Lower margin is less than 5 µv Upper margin is less than 10 µv Lower margin is less than 5 µv more closely examined to confirm seizure activity. Neonatal seizures on the raw EEG signal have been described as rhythmic, sharp, or spiky waveforms that are similar in morphology and last longer than ten seconds. 2 Suspected seizures on the aeeg must be confirmed by reviewing the raw EEG signal because some artifacts (such as muscle artifact) may also cause an intermittent rise in the aeeg (Figure 9). Nurses play a crucial role in the identification of artifact. Diligent documentation of clinical events and nursing interventions will aid in the identification of artifact, such as patting or chest physiotherapy, that can simulate a seizure pattern. Using aeeg as a screening tool for seizures has its limitations. 40 Seizures typically evolve, meaning that they have a beginning, middle, and end, and they can migrate from one area of the brain to another. On limited-channel monitors, this evolution and migration of seizures may not be as clearly evident. Limited channels can also miss focal seizures that do not migrate to the monitored area. For these reasons, a full multichannel ceeg is necessary for a comprehensive look at the whole cortical area. Because aeeg is a compressed record, brief seizures may not be detected, and low-amplitude seizures may not cause a rise in the aeeg. Online tools to detect spikes in the raw EEG pattern are being developed to address these limitations. 41 Conclusion In the case of Baby Jones, with bedside brain monitoring available, NICU staff could initiate monitoring at the time of admission. An abnormal aeeg pattern would provide the neonatal staff with valuable prognostic information. Seizures continuing on the bedside brain monitor, after administration of phenobarbital, would give valuable feedback on the efficacy of the treatment regimen. The information provided by an early aeeg may justify an emergency consultation with the pediatric neurologist and a ceeg during the weekend or at other off-peak times. As researchers explore potential neuroprotective strategies, it is essential to have the technology to identify infants who may benefit and then to monitor the effect of experimental therapies. If the decision in the NICU is to treat seizures, we must attempt to identify both clinical and subclinical seizures, then adequately treat them by monitoring the response to AEDs. As one neurologist pointed out, we would not consider treating a cardiac electrical disturbance (arrhythmia) without monitoring the heart, FIGURE 8 n Electroencephalographic seizure causing a rise in the lower margin and usually the upper margin, creating an arch in the aeeg band. FIGURE 9 n Example of artifact (arrows) raising the aeeg band. VOL. 27, NO. 5, September/october

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9 32. Boylan, G. B., Rennie, J. M., Chorley, G., Pressler, R. M., Fox, G. F., Farrer, K., et al. (2004). Second-line anticonvulsant treatment of neonatal seizures: A video-eeg monitoring study. Neurology, 62, Scher, M. S., Alvin, J., Gaus, L., Minnigh, B., & Painter, M. J. (2003). Uncoupling of EEG-clinical neonatal seizures after antiepileptic drug use. Pediatric Neurology, 28, de Vries, L. S., & Hellstrom-Westas, L. (2005). Role of cerebral function monitoring in the newborn. Archives of Disease in Childhood. Fetal and Neonatal Edition, 90, F201 F Toet, M. C., Groenendaal, F., Osredkar, D., van Huffelen, A. C., & de Vries, L. S. (2005). Postneonatal epilepsy following amplitude-integrated EEG-detected neonatal seizures. Pediatric Neurology, 32, Clancy, R. R., & Legido, A. (1991). Postnatal epilepsy after EEGconfirmed neonatal seizures. Epilepsia, 32, Hellstrom-Westas, L., Rosen, I., de Vries, L. S., & Greisen, G. (2007). Amplitude-integrated EEG classification and interpretation in preterm and term infants. Neoreviews, 7(2), Hellstrom-Westas, L., Rosen, I., & Svenningsen, N. W. (1995). Predictive value of early continuous amplitude integrated EEG recordings on outcome after severe birth asphyxia in full term infants. Archives of Disease in Childhood. Fetal and Neonatal Edition, 72, F34 F Hellstrom-Westas, L., de Vries, L. S., & Rosen, I. (2003). An atlas of amplitude-integrated EEGs in the newborn (1st ed.). London: Parthenon Publishing. 40. Rennie, J. M., Chorley, G., Boylan, G. B., Pressler, R., Nguyen, Y., & Hooper, R. (2004). Non-expert use of the cerebral function monitor for neonatal seizure detection. Archives of Disease in Childhood. Fetal and Neonatal Edition, 89, F37 F Navakatikyan, M. A., Colditz, P. B., Burke, C. J., Inder, T. E., Richmond, J., & Williams, C. E. (2006). Seizure detection algorithm for neonates based on wave-sequence analysis. Clinical Neurophysiology, 117, Vespa, P. (2005). Continuous EEG monitoring for the detection of seizures in traumatic brain injury, infarction, and intracerebral hemorrhage: To detect and protect. Journal of Clinical Neurophysiology, 22, About the Authors Shelly V. Lavery is currently a research nurse with the Victorian Infant Brain Study Group (VIBeS), Melbourne, Australia. She was previously employed as an associate unit manager of the neonatal ICU, Royal Children s Hospital, Melbourne. Shelly received her midwifery certificate at Bellshill, Scotland, and neonatal ICU certificate at Latrobe University, Melbourne. Kathi S. Randall has held a variety of positions in the NICU at Loma Linda University Medical Center over the last 14 years. At the time of writing this article, she was practicing as an NNP in their 80-bed Level III plus ECMO referral center. Kathi has a passion for education of both NICU staff and families. She lectures throughout the U.S. and internationally on a variety of neonatal topics. In addition to her clinical practice, Kathi provides education consultation services to medical device companies and has been a consultant to BrainZ Instruments, the manufacturer of the BRM bedside aeeg device, since they received FDA approval in We thank Barbara Mordue (Loma Linda University Medical Center), Brenda Smith (Utah Valley Regional Medical Center in Provo), and Tom Pantano (BrainZ Instruments) for their critique and helpful comments. For further information, please contact: Shelly V. Lavery, RN, BaHSc Victorian Infant Brain Study Group (VIBeS) Royal Children s Hospital Flemington Road Melbourne, Australia shelly.lavery@rch.org.au VOL. 27, NO. 5, September/october