Analgesia and anesthesia for neonates: Study design and ethical issues

Core Outcome Sets in Child Health: A Systematic Review

IMPORTANCE

Developing core outcome sets is essential to ensure that results of clinical trials are comparable and useful. A number of core outcome sets in pediatrics have been published, but a comprehensive in-depth understanding of core outcome sets in this field is lacking.

OBJECTIVE

To systematically identify core outcome sets in child health, collate the diseases to which core outcome sets have been applied, describe the methods used for development and stakeholder participation, and evaluate the methodological quality of existing core outcome sets.

EVIDENCE REVIEW

MEDLINE, SCOPUS, Cochrane Library, and CINAHL were searched using relevant search terms, such as clinical trials, core outcome, and children, along with relevant websites, such as Core Outcome Measures in Effectiveness Trials (COMET). Four researchers worked in teams of 2, performed literature screening and data extraction, and evaluated the methodological quality of core outcome sets using the Core Outcome Set-Standards for Development (COS-STAD).

FINDINGS

A total of 77 pediatric core outcome sets were identified, mainly developed by organizations or researchers in Europe, North America, and Australia and mostly from the UK (22 [29%]) and the US (22 [29%]). A total of 77 conditions were addressed; the most frequent International Classification of Diseases, 11th Revision category was diseases of the digestive system (14 [18%]). Most of the outcomes in pediatric core outcome sets were unordered (34 [44%]) or presented in custom classifications (29 [38%]). Core outcome sets used 1 or more of 8 development methods; the most frequent combination of methods was systematic review/literature review/scoping review, together with the Delphi approach and consensus for decision-making (10 [14%]). Among the 6 main types of stakeholders, clinical experts were the most frequently involved (74 [100%]), while industry representatives were rarely involved (4 [5%]). Only 6 core outcome sets (8%) met the 12 criteria of COS-STAD.

CONCLUSIONS AND RELEVANCE

Future quality of pediatric core outcome sets should be improved based on the standards proposed by the COMET initiative, while core outcome sets methodology and reporting standards should be extended to pediatric populations to help improve the quality of core outcome sets in child health. In addition, the COMET outcome taxonomy should also add items applicable to children.

Dysmaturation of Premature Brain: Importance, Cellular Mechanisms, and Potential Interventions

Prematurity, especially preterm birth (less than 32 weeks' gestation), is common and associated with high rates of both survival and neurodevelopmental disability, especially apparent in cognitive spheres. The neuropathological substrate of this disability is now recognized to be related to a variety of dysmaturational disturbances of the brain. These disturbances follow initial brain injury, particularly cerebral white matter injury, and involve many of the extraordinary array of developmental events active in cerebral white and gray matter structures during the premature period. This review delineates these developmental events and the dysmaturational disturbances that occur in premature infants. The cellular mechanisms involved in the genesis of the dysmaturation are emphasized, with particular focus on the preoligodendrocyte. A central role for the diffusely distributed activated microglia and reactive astrocytes in the dysmaturation is now apparent. As these dysmaturational cellular mechanisms appear to occur over a relatively long time window, interventions to prevent or ameliorate the dysmaturation, that is, neurorestorative interventions, seem possible. Such interventions include pharmacologic agents, especially erythropoietin, and particular attention has also been paid to such nutritional factors as quality and source of milk, breastfeeding, polyunsaturated fatty acids, iron, and zinc. Recent studies also suggest a potent role for interventions directed at various experiential factors in the neonatal period and infancy, i.e., provision of optimal auditory and visual exposures, minimization of pain and stress, and a variety of other means of environmental behavioral enrichment, in enhancing brain development.

The challenge of developing pain medications for children: therapeutic needs and future perspectives

It is broadly accepted that children of all age groups including (preterm) neonates and young infants can perceive pain and that there is an absolute need to treat their pain safely and effectively. The approved treatment options for children, particularly (preterm) neonates and young infants, are very limited with only a few medications specifically labelled for this population. This article presents the challenges of developing pain medications for children. A short overview gives information on pain in children, including pain perception, prevalence of pain and the long-term consequences of leaving pain untreated in this vulnerable population. Current pain management practices are briefly discussed. The challenges of conducting pediatric clinical trials in general and trials involving analgesic medications in particular within the regulatory framework available to develop these medications for children are presented. Emphasis is given to the operational hurdles faced in conducting a pediatric clinical trial program. Some suggestions to overcome these hurdles are provided based on our experience during the pediatric trial program for the strong analgesic tapentadol used for the treatment of moderate to severe acute pain.

Effects of Covering the Eyes versus Playing Intrauterine Sounds on Premature Infants' Pain and Physiological Parameters during Venipuncture

BACKGROUND

There is a need to assess the impact of initiatives to reduce exposure to environmental light and sound in preterm infants undergoing painful interventions in neonatal intensive care units.

OBJECTIVES

In this study, we aimed to identify the effect of covering the eyes and playing the intrauterine ambient sounds on premature infants' pain and physiological parameters during venipuncture.

METHODS

This was a randomized controlled trial. Ninety-four preterm infants were randomly divided into three groups: intrauterine sounds (n=32), covered eyes (n=32), and control (n=30) groups. Data were collected on the Preterm Infant Information Form, Preterm Infant Follow-up Form, and Neonatal Infant Pain Scale (NIPS), used to assess pain.

RESULTS

A significant difference was found between the intervention and control groups' NIPS score after venipuncture, which was primarily due to covered eyes' group. No significant difference was found between the intervention and control groups' NIPS score during venipuncture. In addition, no significant difference was found between the intervention and control groups of infants physiological parameters before, during, and after venipuncture. The practice of covering preterm infants' eyes during venipuncture positively affected their pain scores after venipuncture.

CLINICAL IMPLICATIONS

The effect of covering the eyes and playing the intrauterine ambient sounds in preterm infants may be recommended as simple, safe, and supportive stimuli that facilitate positive effects during painful procedures.

Design and conduct of early phase drug studies in children: challenges and opportunities

It has historically been very difficult to conduct early phase drug studies in children for a number of reasons related to ethics, acceptability, rarity, standardization, end points, safety, dosing and feasibility. Over the past decade there have been a number of developments including novel clinical trial design, in silico pharmacology and microdosing that have significantly enhanced the ability of investigators to conduct early phase drug studies in children. While the evolution of drug therapy is creating a series of new challenges, there has never been a better time for conducting drug studies in children.

Combined non-pharmacological interventions for newborn pain relief in two degrees of pain procedures: A randomized clinical trial

BACKGROUND

Non-pharmacological interventions are effective neonatal pain reduction strategies. We aimed to study the effects of non-nutritive sucking (NNS) and swaddling on infants' behavioural and physiological parameters during shallow or deep heel stick procedures.

METHOD

In this prospective, multi-centred, randomized controlled clinical trial, we enrolled 671 newborns. The infants undergoing shallow or deep heel stick procedures were randomized into four groups: oral sucrose (routine care, group S), oral sucrose combined with NNS (group NS), oral sucrose combined with swaddling (group SS) and oral sucrose combined with NNS and swaddling (group NSS). The behavioural responses were evaluated by the Revised Neonatal Facial Coding System and the physiological signals were monitored by electrocardiogram monitors.

RESULTS

A significant synergistic analgesic effect was observed between the NS and SS groups in both the shallow (F = 5.952, p = 0.015) and deep heel stick (F = 7.452, p = 0.007) procedure. NSS group exhibited the lowest pain score. For the deep heel stick procedure, the NS group had a significantly lower increase in heart rate (HR)% and decrease in SPO2 % than the S group (F = 17.540, p = 0.000, F = 10.472, p = 0.001), while this difference was not observed in the shallow heel stick procedure. No difference was found between the S and SS groups, in terms of different physiological parameters.

CONCLUSION

Non-nutritive sucking and swaddling had synergistic effects on pain relief when used with oral sucrose. For the deep heel stick procedure, oral sucrose combined with NNS and swaddling provided the best pain relief effect. For the shallow heel stick procedure, addition of NNS and swaddling did not improve the effects.

The long-term impact of early life pain on adult responses to anxiety and stress: Historical perspectives and empirical evidence

Approximately 1 in 6 infants are born prematurely each year. Typically, these infants spend 25 days in the Neonatal Intensive Care Unit (NICU) where they experience 10-18 painful and inflammatory procedures each day. Remarkably, pre-emptive analgesics and/or anesthesia are administered less than 25% of the time. Unalleviated pain during the perinatal period is associated with permanent decreases in pain sensitivity, blunted cortisol responses and high rates of neuropsychiatric disorders. To date, the mechanism(s) by which these long-term changes in stress and pain behavior occur, and whether such alterations can be prevented by appropriate analgesia at the time of insult, remains unclear. Work in our lab using a rodent model of early life pain suggests that inflammatory pain experienced on the day of birth blunts adult responses to stress- and pain-provoking stimuli, and dysregulates the hypothalamic pituitary adrenal (HPA) axis in part through a permanent upregulation in central endogenous opioid tone. This review focuses on the long-term impact of neonatal inflammatory pain on adult anxiety- and stress-related responses, and underlying neuroanatomical changes in the context of endogenous pain control and the HPA axis. These two systems are in a state of exaggerated developmental plasticity early in postnatal life, and work in concert to respond to noxious or aversive stimuli. We present empirical evidence from animal and clinical studies, and discuss historical perspectives underlying the lack of analgesia/anesthetic use for early life pain in the modern NICU.

Anesthetic use in newborn infants: the urgent need for rigorous evaluation

Approximately 1.5 million neonates receive general anesthesia each year for a surgical procedure. Despite this being an essential practice, a number of recent studies now indicate that anesthetic exposure could cause toxicity and neuronal apoptosis in the developing brain. This could potentially influence long-term neurodevelopmental outcome, especially premature infants in need of multiple surgical procedures. Most anesthetic drugs routinely administered to neonates have not been adequately tested for safety or efficacy. Given the number of confounders, dosing is often extrapolated from adults. This is concerning since many different drugs can be administered concurrently, with few of these agents actually approved for use by the Food and Drug Administration. Since 1997, legislation has been passed in the United States and abroad encouraging more drug investigation in infants and children. This has resulted in over 500 labeling changes to products regarding safety and efficacy in various pediatric age groups. However, only three drugs routinely used as anesthetic agents in newborn infants have had any updated labeling (none in very premature infants). This "off-label" use without adequate testing must be addressed. Therefore, more clinical trials of common anesthetic agents used alone and in combination in neonates are urgently needed.

Neuraxial analgesia in neonates and infants: a review of clinical and preclinical strategies for the development of safety and efficacy data

Neuraxial drugs provide robust pain control, have the potential to improve outcomes, and are an important component of the perioperative care of children. Opioids or clonidine improves analgesia when added to perioperative epidural infusions; analgesia is significantly prolonged by the addition of clonidine, ketamine, neostigmine, or tramadol to single-shot caudal injections of local anesthetic; and neonatal intrathecal anesthesia/analgesia is increasing in some centers. However, it is difficult to determine the relative risk-benefit of different techniques and drugs without detailed and sensitive data related to analgesia requirements, side effects, and follow-up. Current data related to benefits and complications in neonates and infants are summarized, but variability in current neuraxial drug use reflects the relative lack of high-quality evidence. Recent preclinical reports of adverse effects of general anesthetics on the developing brain have increased awareness of the potential benefit of neuraxial anesthesia/analgesia to avoid or reduce general anesthetic dose requirements. However, the developing spinal cord is also vulnerable to drug-related toxicity, and although there are well-established preclinical models and criteria for assessing spinal cord toxicity in adult animals, until recently there had been no systematic evaluation during early life. Therefore, in the second half of this review, we present preclinical data evaluating age-dependent changes in the pharmacodynamic response to different spinal analgesics, and recent studies evaluating spinal toxicity in specific developmental models. Finally, we advocate use of neuraxial drugs with the widest demonstrable safety margin and suggest minimum standards for preclinical evaluation before adoption of new analgesics or preparations into routine clinical practice.

Warmth is analgesic in healthy newborns

This study identifies a behavioral and nonpharmacologic means of preventing and reducing newborn pain. Our objective was to determine whether warmth is analgesic in newborn infants undergoing vaccination-a routine painful hospital procedure. We used a prospective randomized controlled trial of 47 healthy full-term newborn infants. Infants were randomized into 1 of 3 conditions prior to vaccination: warmth exposure, pacifier suckling, or sucrose taste. Crying, grimacing, and heart rate differences were analyzed between groups before, during, and after vaccination as outcome measures. Warmer infants cried significantly less than sucrose taste or pacifier suckling after vaccination. Heart rate patterns reflected this analgesia. Core temperature did not differ between study groups. Providing natural warmth to newborn infants during a painful procedure decreases the crying and grimacing on par with the "gold" standard treatments of sucrose or pacifier.

Acute pain and a motivational pathway in adult rats: influence of early life pain experience

Background

The importance of neonatal experience upon behaviour in later life is increasingly recognised. The overlap between pain and reward pathways led us to hypothesise that neonatal pain experience influences reward-related pathways and behaviours in adulthood.

Methodology/Principal Findings

Rat pups received repeat plantar skin incisions (neonatal IN) or control procedures (neonatal anesthesia only, AN) at postnatal days (P)3, 10 and 17. When adult, rats with neonatal ‘pain history’ showed greater sensory sensitivity than control rats following acute plantar skin incision. Motivational behaviour in the two groups of rats was tested in a novelty-induced hypophagia (NIH) paradigm. The sensitivity of this paradigm to pain-induced changes in motivational behaviour was shown by significant increases in the time spent in the central zone of the arena (43.7±5.9% vs. 22.5±6.7%, p<0.05), close to centrally placed food treats, and decreased number of rears (9.5±1.4 vs. 19.2±2.3, p<0.001) in rats with acute plantar skin incision compared to naive, uninjured animals. Rats with a neonatal ‘pain history’ showed the same pain-induced behaviour in the novelty-induced hypophagia paradigm as controls. However, differences were observed in reward-related neural activity between the two groups. Two hours after behavioural testing, brains were harvested and neuronal activity mapped using c-Fos expression in lateral hypothalamic orexin neurons, part of a specific reward seeking pathway. Pain-induced activity in orexin neurons of control rats (18.4±2.8%) was the same as in uninjured naive animals (15.5±2.6%), but in those rats with a ‘pain history’, orexinergic activity was significantly increased (27.2±4.1%, p<0.01). Furthermore the extent of orexin neuron activation in individual rats with a ‘pain history’ was highly correlated with their motivational behaviour (r = −0.86, p = 0.01).

Conclusions/Significance

These results show that acute pain alters motivational behaviour and that neonatal pain experience causes long-term changes in brain motivational orexinergic pathways, known to modulate mesolimbic dopaminergic reward circuitry.

Pediatric analgesic clinical trial designs, measures, and extrapolation: report of an FDA scientific workshop

Analgesic trials pose unique scientific, ethical, and practical challenges in pediatrics. Participants in a scientific workshop sponsored by the US Food and Drug Administration developed consensus on aspects of pediatric analgesic clinical trial design. The standard parallel-placebo analgesic trial design commonly used for adults has ethical and practical difficulties in pediatrics, due to the likelihood of subjects experiencing pain for extended periods of time. Immediate-rescue designs using opioid-sparing, rather than pain scores, as a primary outcome measure have been successfully used in pediatric analgesic efficacy trials. These designs maintain some of the scientific benefits of blinding, with some ethical and practical advantages over traditional designs. Preferred outcome measures were recommended for each age group. Acute pain trials are feasible for children undergoing surgery. Pharmacodynamic responses to opioids, local anesthetics, acetaminophen, and nonsteroidal antiinflammatory drugs appear substantially mature by age 2 years. There is currently no clear evidence for analgesic efficacy of acetaminophen or nonsteroidal antiinflammatory drugs in neonates or infants younger than 3 months of age. Small sample designs, including cross-over trials and N of 1 trials, for particular pediatric chronic pain conditions and for studies of pain and irritability in pediatric palliative care should be considered. Pediatric analgesic trials can be improved by using innovative study designs and outcome measures specific for children. Multicenter consortia will help to facilitate adequately powered pediatric analgesic trials.

Oral sucrose as an analgesic drug for procedural pain in newborn infants: a randomised controlled trial

BACKGROUND

Many infants admitted to hospital undergo repeated invasive procedures. Oral sucrose is frequently given to relieve procedural pain in neonates on the basis of its effect on behavioural and physiological pain scores. We assessed whether sucrose administration reduces pain-specific brain and spinal cord activity after an acute noxious procedure in newborn infants.

METHODS

In this double-blind, randomised controlled trial, 59 newborn infants at University College Hospital (London, UK) were randomly assigned to receive 0·5 mL 24% sucrose solution or 0·5 mL sterile water 2 min before undergoing a clinically required heel lance. Randomisation was by a computer-generated randomisation code, and researchers, clinicians, participants, and parents were masked to the identity of the solutions. The primary outcome was pain-specific brain activity evoked by one time-locked heel lance, recorded with electroencephalography and identified by principal component analysis. Secondary measures were baseline behavioural and physiological measures, observational pain scores (PIPP), and spinal nociceptive reflex withdrawal activity. Data were analysed per protocol. This study is registered, number ISRCTN78390996.

FINDINGS

29 infants were assigned to receive sucrose and 30 to sterilised water; 20 and 24 infants, respectively, were included in the analysis of the primary outcome measure. Nociceptive brain activity after the noxious heel lance did not differ significantly between infants who received sucrose and those who received sterile water (sucrose: mean 0·10, 95% CI 0·04-0·16; sterile water: mean 0·08, 0·04-0·12; p=0·46). No significant difference was recorded between the sucrose and sterile water groups in the magnitude or latency of the spinal nociceptive reflex withdrawal recorded from the biceps femoris of the stimulated leg. The PIPP score was significantly lower in infants given sucrose than in those given sterile water (mean 5·8, 95% CI 3·7-7·8 vs 8·5, 7·3-9·8; p=0·02) and significantly more infants had no change in facial expression after sucrose administration (seven of 20 [35%] vs none of 24; p<0·0001).

INTERPRETATION

Our data suggest that oral sucrose does not significantly affect activity in neonatal brain or spinal cord nociceptive circuits, and therefore might not be an effective analgesic drug. The ability of sucrose to reduce clinical observational scores after noxious events in newborn infants should not be interpreted as pain relief.

FUNDING

Medical Research Council.

Measurement issues in trials of pediatric acute diarrheal diseases: a systematic review

BACKGROUND

Worldwide, diarrheal diseases rank second among conditions that afflict children. Despite the disease burden, there is limited consensus on how to define and measure pediatric acute diarrhea in trials.

OBJECTIVES

In RCTs of children involving acute diarrhea as the primary outcome, we documented (1) how acute diarrhea and its resolution were defined, (2) all primary outcomes, (3) the psychometric properties of instruments used to measure acute diarrhea and (4) the methodologic quality of included trials, as reported.

METHODS

We searched CENTRAL, Embase, Global Health, and Medline from inception to February 2009. English-language RCTs of children younger than 19 years that measured acute diarrhea as a primary outcome were chosen.

RESULTS

We identified 138 RCTs reporting on 1 or more primary outcomes related to pediatric acute diarrhea/diseases. Included trials used 64 unique definitions of diarrhea, 69 unique definitions of diarrhea resolution, and 46 unique primary outcomes. The majority of included trials evaluated short-term clinical disease activity (incidence and duration of diarrhea), laboratory outcomes, or a composite of these end points. Thirty-two trials used instruments (eg, single and multidomain scoring systems) to support assessment of disease activity. Of these, 3 trials stated that their instrument was valid; however, none of the trials (or their citations) reported evidence of this validity. The overall methodologic quality of included trials was good.

CONCLUSIONS

Even in what would be considered methodologically sound clinical trials, definitions of diarrhea, primary outcomes, and instruments employed in RCTs of pediatric acute diarrhea are heterogeneous, lack evidence of validity, and focus on indices that may not be important to participants.

The use of oral ketamine for analgesia with dressing change in an infant with epidermolysis bullosa: report of a case

Epidermolysis bullosa (EB) describes a spectrum of disease from occasional bullae and callus formation to a debilitating life-threatening condition. In this study, we report the use of intravenous ketamine given orally to an infant with a phenotypically severe form of EB simplex, Dowling-Meara subtype, to achieve analgesia during painful dressing changes.

Avaliação da dor em recém-nascidos prematuros durante a fisioterapia respiratória

OBJETIVOS: avaliar a presença de dor durante a fisioterapia respiratória em prematuros submetidos à ventilação mecânica. MÉTODOS: estudo prospectivo realizado entre fevereiro de 2003 e maio de 2004, sendo incluídos prematuros com idade gestacional <34 semanas e peso de nascimento <1500 g, submetidos à ventilação mecânica. Os recém-nascidos receberam os procedimentos de fisioterapia respiratória conforme suas necessidades e rotina do serviço. Para a avaliação da dor foi utilizada a Escala de Dor para Recém-Nascidos=Neonatal Infant Pain Scale (NIPS) antes e após os procedimentos de fisioterapia respiratória e o procedimento de aspiração endotraqueal e de vias aéreas superiores. RESULTADOS foram estudados 30 prematuros (15 masculinos), com idade gestacional média ao nascimento de 30,70±2,10 semanas e peso médio de nascimento de 1010,70±294,60 gramas. Cada recém-nascido recebeu em média 7.33 sessões de fisioterapia. Verificou-se não haver diferença estatisticamente significante entre a presença de dor antes e após a fisioterapia, (p=0,09); entretanto, houve diferença estatisticamente significante entre a presença de dor antes e depois o procedimento de aspiração (p<0,001). CONCLUSÕES: a fisioterapia respiratória não foi desencadeante de estímulos dolorosos, porém o procedimento de aspiração, por ser invasivo, mostrou-se potencialmente doloroso, devendo ser realizado somente quando estritamente necessário.

Effectiveness of sucrose analgesia in newborns undergoing painful medical procedures

BACKGROUND

Sucrose is widely used to manage procedural pain in term newborns despite a lack of evidence of its effectiveness for different procedures and infant populations. Our objectives were to evaluate the effectiveness and safety of sucrose in newborns undergoing various medical procedures within 2 days of birth.

METHODS

We performed a double-blind, randomized controlled trial. We included newborns (>or= 36 weeks gestation) of diabetic mothers and nondiabetic mothers. Each newborn received 2 mL of a 24%-sucrose or placebo solution before all procedures. We used the Premature Infant Pain Profile to assess pain during intramuscular injection of vitamin K, venipuncture for the newborn screening test and the first 3 heel lances for glucose monitoring (newborns of diabetic mothers only). Scores ranged from from 0 (no pain) to 18 (maximum pain).

RESULTS

We included 240 newborns (120 from diabetic mothers, 120 from nondiabetic mothers). The overall mean pain score was lower among newborns who received sucrose than among those who received a placebo (mean difference -1.3, 95% confidence interval [CI] -2.0 to -0.6). We found that pain scores during intramuscular injection did not differ significantly between the sucrose and placebo groups for newborns of diabetic or nondiabetic mothers (newborns of nondiabetic mothers: mean difference -1.1, 95% CI -2.4 to 0.2; newborns of diabetic mothers: mean difference -1.0, 95% CI -2.4 to 0.4). During venipuncture, newborns who received sucrose had lower pain scores compared with those who received a placebo (newborns of nondiabetic mothers: mean difference -3.2, 95% CI -4.6 to -1.8; newborns of diabetic mothers: mean difference -2.4, 95% CI -3.8 to -1.0). Among newborns of diabetic mothers, there was no difference in pain during the first 3 heel lances or mean glucose levels between the sucrose and placebo groups (p = 0.94 and p = 0.29 respectively).

INTERPRETATION

We found a modest reduction of pain in newborns of both diabetic and nondiabetic mothers when sucrose was used for all medical procedures performed in the first 2 days after birth. However, when each procedure was analyzed separately, we found that the effectiveness of sucrose was limited to venipuncture for the newborn screening test. (http://Clinicaltrials.gov trial register no. NCT00213213.).

A systematic review of studies that aim to determine which outcomes to measure in clinical trials in children

BACKGROUND

In clinical trials the selection of appropriate outcomes is crucial to the assessment of whether one intervention is better than another. Selection of inappropriate outcomes can compromise the utility of a trial. However, the process of selecting the most suitable outcomes to include can be complex. Our aim was to systematically review studies that address the process of selecting outcomes or outcome domains to measure in clinical trials in children.

METHODS AND FINDINGS

We searched Cochrane databases (no date restrictions) in December 2006; and MEDLINE (1950 to 2006), CINAHL (1982 to 2006), and SCOPUS (1966 to 2006) in January 2007 for studies of the selection of outcomes for use in clinical trials in children. We also asked a group of experts in paediatric clinical research to refer us to any other relevant studies. From these articles we extracted data on the clinical condition of interest, description of the method used to select outcomes, the people involved in the selection process, the outcomes selected, and limitations of the method as defined by the authors. The literature search identified 8,889 potentially relevant abstracts. Of these, 70 were retrieved, and 25 were included in the review. These studies described the work of 13 collaborations representing various paediatric specialties including critical care, gastroenterology, haematology, psychiatry, neurology, respiratory paediatrics, rheumatology, neonatal medicine, and dentistry. Two groups utilised the Delphi technique, one used the nominal group technique, and one used both methods to reach a consensus about which outcomes should be measured in clinical trials. Other groups used semistructured discussion, and one group used a questionnaire-based survey. The collaborations involved clinical experts, research experts, and industry representatives. Three groups involved parents of children affected by the particular condition.

CONCLUSIONS

Very few studies address the appropriate choice of outcomes for clinical research with children, and in most paediatric specialties no research has been undertaken. Among the studies we did assess, very few involved parents or children in selecting outcomes that should be measured, and none directly involved children. Research should be undertaken to identify the best way to involve parents and children in assessing which outcomes should be measured in clinical trials.

Pain in children: recent advances and ongoing challenges

Significant advances in the assessment and management of acute pain in children have been made, and are supported by an increase in the availability and accessibility of evidence-based data. However, methodological and practical issues in the design and performance of clinical paediatric trials limit the quantity, and may influence the quality, of current data, which lags behind that available for adult practice. Collaborations within research networks, which incorporate both preclinical and clinical studies, may increase the feasibility and specificity of future trials. In early life, the developing nervous system responds differently to pain, analgesia, and injury, resulting in effects not seen in later life and which may have long-term consequences. Translational laboratory studies further our understanding of developmental changes in nociceptor pathway structure and function, analgesic pharmacodynamics, and the impact of different forms of injury. Chronic pain in children has a negative impact on quality of life, resulting in social and emotional consequences for both the child and the family. Despite age-related differences in many chronic pain conditions, such as neuropathic pain, management in children is often empirically based on data from studies in adults. There is a major need for further clinical research, training of health-care providers, and increased resources, to improve management and outcomes for children with chronic pain.

Initial validation of the Behavioral Indicators of Infant Pain (BIIP)

Accurate pain assessment in preterm infants in the neonatal intensive care unit (NICU) is complex. Infants who are born at early gestational ages (GA), and who have had greater early pain exposure, have dampened facial responses which may lead to under-treatment. Since behavioral and physiological responses to pain in infants are often dissociated, using multidimensional scales which combine these indicators into a single score may limit our ability to determine the effects of interventions on each system. Our aim was to design a unidimensional scale which would combine the relatively most specific, individual, behavioral indicators for assessing acute pain in this population. The Behavioral Indicators of Infant Pain (BIIP) combines sleep/wake states, 5 facial actions and 2 hand actions. Ninety-two infants born between 23 and 32 weeks GA were assessed during 3, 1 min Phases of blood collection. Outcome measures included changes in BIIP and in Neonatal Infant Pain Scale (NIPS) scores coded in real time from continuous bedside video recordings; changes in heart rate (HR) were obtained using custom physiological processing software. Scores on the BIIP changed significantly across Phases of blood collection (p<0.01). Internal consistency (0.82) and inter-rater reliability (0.80-0.92) were high. Correlations between the BIIP and NIPS were modest (r=0.64, p<0.01) as were correlations between the BIIP and mean heart rate (r=0.45, p<0.01). In this initial study, the BIIP has been shown to be a reliable, valid scale for assessing acute pain in preterm infants in the NICU.

Neonatal Facial Coding System Scores and Spectral Characteristics of Infant Crying During Newborn Circumcision

OBJECTIVE

To determine the relations between Neonatal Facial Coding System (NFCS) scores and measures of infant crying during newborn circumcision.

METHODS

Video and audio recordings were made of infant facial activity and cry sounds, respectively, during the lysis phase of circumcisions of 44 healthy term males (<3 d of age). All infants received topical analgesia before circumcision. NFCS scores were determined by blinded assistant from video recordings of facial activity. Measures of infant crying were determined via spectrum analysis of audio recordings by a blinded, independent researcher. Pearson product-moment correlations were used to examine relationship between NFCS scores and measures of crying. Principal component factor analysis detected dimensions underlying related measures of crying. Factor scores from a factor analysis were used in stepwise linear regression to predict NFCS scores.

RESULTS

Higher NFCS scores correlated with lower peak fundamental frequency of crying (P<0.01) and with higher amplitudes of crying at peak fundamental frequency and dominant frequency and in overall cry sample (P<0.01). The factor analysis showed 3 significant orthogonal dimensions underlying measures of crying: Power and Velocity (amplitude and rapidity), Pitch of Crying (frequency characteristics), and Infant Arousal (turbulence and intensity) accounting for 42.3%, 17.8%, and 14.6% of variance, respectively. A regression analysis showed all 3 factor scores accounted for significant and separate portions of variance (P<0.001). The best predictor of NFCS score was Power and Velocity (P<0.002), followed by Infant Arousal (P<0.002), and Pitch of Crying (P<0.007).

DISCUSSION

These data provide some of the first known evidence linking specific measures of infant crying with an independent, validated measure of pain.

Prevention and management of pain in the neonate. An update

The prevention of pain in neonates should be the goal of all caregivers, because repeated painful exposures have the potential for deleterious consequences. Neonates at greatest risk of neurodevelopmental impairment as a result of preterm birth (ie, the smallest and sickest) are also those most likely to be exposed to the greatest number of painful stimuli in the NICU. Although there are major gaps in our knowledge regarding the most effective way to prevent and relieve pain in neonates, proven and safe therapies are currently underused for routine minor yet painful procedures. Every health care facility caring for neonates should implement an effective pain-prevention program, which includes strategies for routinely assessing pain, minimizing the number of painful procedures performed, effectively using pharmacologic and nonpharmacologic therapies for the prevention of pain associated with routine minor procedures, and eliminating pain associated with surgery and other major procedures.

Potentially toxic effects of anaesthetics on the developing central nervous system

A growing body of experimental evidence suggests that anaesthetics, by influencing GABAergic and glutaminergic neural signalling, can have adverse effects on the developing central nervous system. The biological foundation for this is that gamma-aminobutyric acid and glutamate could act non-synaptically, in addition to their role in neurotransmission in the adult brain, in the regulation of neuronal development in the central nervous system. These neurotransmitters and their receptors are expressed from very early stages of central nervous system development and appear to influence neural progenitor proliferation, cell migration and neuronal differentiation. During the synaptogenetic period, pharmacological blockade of N-methyl-d-aspartate (NMDA)-type glutamate receptors as well as stimulation of GABAA receptors has been reported to be associated with increased apoptosis in the developing brain. Importantly, recent data suggest that even low, non-apoptogenic concentrations of anaesthetics can perturb neuronal dendritic development and thus could potentially lead to impairment of developing neuronal networks. The extrapolation of these experimental observations to clinical practice is of course very difficult and requires extreme caution as differences in drug concentrations and exposure times as well as interspecies variations are all important confounding variables. While clinicians should clearly not withhold anaesthesia based on current animal studies, these observations should urge more laboratory and clinical research to further elucidate this issue.

Ethical challenges in neonatal research: Summary report of the ethics group of the newborn drug development initiative

BACKGROUND

The Newborn Drug Development Initiative (NDDI) was established to address the lack of substantive data supporting efficacy and safety of drugs in the neonate.

OBJECTIVE

This commentary summarizes some of the ethical issues involved in neonatal drug development.

METHODS

At the NDDI workshop held March 29 and 30, 2004, in Baltimore, Maryland, members of the Ethics Group were dispersed among the subspecialty groups before convening to discuss common ethical themes. The Ethics Group then met together to identify and discuss those ethical themes that were both important and shared among the groups. These themes are discussed and illustrated with the other NDDI group reports. This workshop was cosponsored by the National Institute of Child Health and Human Development and the US Food and Drug Administration.

RESULTS

Neonatal drug research is scientifically and ethically necessary to establish the efficacy and safety of drugs widely used in newborn medicine. However, research involving neonates must be carefully designed to balance potential risks and benefits, with consideration given to the component analysis of risk. The protocols proposed by the NDDI groups would be considered greater than minimal risk and offering prospect for direct benefit, thus adhering to the Department of Health and Human Services' pediatric research regulations (Subpart D). The NDDI groups all proposed randomized controlled clinical trials, with careful attention to scientifically and ethically appropriate control groups. Multiple regulatory bodies have affirmed that in the absence of proven effective treatment or when a proven treatment offers marginal benefits, study designs with placebo controls are ethical. Obtaining parental permission is a complex issue, with a paucity of evidence describing the feasibility of informed and voluntary consent under conditions of duress and a short therapeutic window. The Subpart D regulations offer sufficient protection to critically ill neonates. The application of the revised Subpart B regulations would restrict the use of a waiver of consent for minimal risk research and for emergency research, and would not allow research that offers no direct benefit and no more than a minor increase over minimal risk.

CONCLUSIONS

Multisite collaboration involving standards of care and institutional review board procedures may be important for establishing scientific and ethical consistency. Ongoing dialogue among researchers, clinicians, parents, and other interested parties is essential to promoting ethically and scientifically sound neonatal clinical research.

Prevention and management of pain in the neonate: an update

The prevention of pain in neonates should be the goal of all caregivers, because repeated painful exposures have the potential for deleterious consequences. Neonates at greatest risk of neurodevelopmental impairment as a result of preterm birth (ie, the smallest and sickest) are also those most likely to be exposed to the greatest number of painful stimuli in the NICU. Although there are major gaps in our knowledge regarding the most effective way to prevent and relieve pain in neonates, proven and safe therapies are currently underused for routine minor yet painful procedures. Every health care facility caring for neonates should implement an effective pain-prevention program, which includes strategies for routinely assessing pain, minimizing the number of painful procedures performed, effectively using pharmacologic and nonpharmacologic therapies for the prevention of pain associated with routine minor procedures, and eliminating pain associated with surgery and other major procedures.

Assessing postoperative pain in neonates: a multicenter observational study

OBJECTIVE

A multicenter observational study was conducted to evaluate the practices of postoperative pain assessment and management in neonates to identify specific targets for improvement in clinical practice.

METHODS

Ten participating NICUs collected data for the 72 hours after a surgical operation on 25 consecutive neonates (N = 250), including demographics, principal diagnoses, operative procedure, other painful procedures, pain assessments, interventions (pharmacologic and nonpharmacologic), and adverse events in neonates who underwent minor and major surgery. Descriptive and logistic-regression analyses were performed by using SPSS and Stata.

RESULTS

The neonates studied had a birth weight of 2.4 +/- 1.0 kg (mean +/- SD) and gestational age of 36 +/- 4.3 weeks; 57% were male, and length of hospital stay was 23.5 +/- 30.0 days. Participating hospitals used 7 different numeric pain scales, with nursing pain assessments documented for 88% (n = 220) of the patients and physician pain assessments documented for 9% (n = 23) of the patients. Opioids (84% vs 60%) and benzodiazepines (24% vs 11%) were used more commonly after major surgery than minor surgery, and a small proportion (7% major surgery, 12% minor surgery) received no analgesia. Logistic-regression analyses showed that physician pain assessment was the only significant predictor of postsurgical analgesic use, whereas major surgery and postnatal age in days did not seem to contribute. Physician pain assessment was documented for 23 patients; 22 of these received postoperative analgesia.

CONCLUSIONS

Documentation of postoperative pain assessment and management in neonates was extremely variable among the participating hospitals. Pain assessment by physicians must be emphasized, in addition to developing evidence-based guidelines for postoperative care and educating professional staff to improve postoperative pain control in neonates.

Pain assessment: current status and challenges

Neonatal pain assessment has received much attention over the past decade. Behavioural indicators of pain include facial action, body movement and tone, cry, state/sleep, and consolability. Physiological indicators of pain include increased heart rate, respiratory rate, and blood pressure, as well as decreased heart rate variability and oxygen desaturation. Pain assessment in neonates is difficult in neurologically compromised, chemically paralyzed, and non-responsive infants. Multiple pain assessment tools are summarized. Pain assessment and management protocols are delineated.

Pain control: opioid dosing, population kinetics and side-effects

Neonates undergoing invasive procedures, postoperative pain or ventilatory support commonly receive opioids for treating pain and stress. Randomized clinical trials have examined the benefits and adverse effects of morphine or fentanyl for ventilated neonates and other indications. This paper summarizes the current evidence for opioid dosing in newborns, reviews their side-effects and explains the use of population kinetics and non-linear mixed-effects modeling to analyze the data from clinical trials. Opioid use should be reserved for severe pain postoperatively or during intensive care in neonates, using continuous infusions rather than intermittent boluses. The safety and efficacy data from prolonged opioid use, particularly on the long-term outcomes of neonates, is still lacking. The pharmacodynamics and pharmacogenetics of opioid use in infancy needs further investigation, using non-linear mixed-effects models to drive individualized therapy. The current interest in opioid research will reap rich dividends in providing pain relief for neonates and avoiding dangerous side effects.