Pharmacological treatment of neonatal pain: in search of a new equipoise

Global cross-sectional survey on neonatal pharmacologic sedation and analgesia practices and pain assessment tools: impact of the sociodemographic index (SDI)

BACKGROUND

There is variability in the use of sedatives and analgesics in neonatal intensive care units (NICUs). We aimed to investigate the use of analgesics and sedatives and the management of neonatal pain and distress.

METHODS

This was a global, prospective, cross-sectional study. A survey was distributed May-November 2022. The primary outcome of this research was to compare results between countries depending on their socio-sanitary level using the sociodemographic index (SDI). We organized results based on geographical location.

RESULTS

The survey collected 1304 responses, but we analyzed 924 responses after database cleaning. Responses from 98 different countries were analyzed. More than 60% of NICUs reported having an analgosedation guideline, and one-third of respondents used neonatal pain scales in more than 80% of neonates. We found differences in the management of sedation and analgesia between NICUs on different continents, but especially between countries with different SDIs. Countries with a higher SDI had greater availability of and adherence to analgosedation guidelines, as well as higher rates of analgosedation for painful or distressing procedures. Countries with different SDIs reported differences in analgosedation for neonatal intubation, invasive ventilation, and therapeutic hypothermia, among others.

CONCLUSIONS

Socio-economic status of countries impacts on neonatal analgosedation management.

IMPACT

There is significant variability in the pain management practices in neonates. There is a lack of knowledge related to how neonatal pain management practices differ between regions. Sociodemographic index is a key factor associated with differences in neonatal pain management practices across global regions.

Systemic opioids versus other analgesics and sedatives for postoperative pain in neonates

BACKGROUND

Neonates may undergo surgery because of malformations such as diaphragmatic hernia, gastroschisis, congenital heart disease, and hypertrophic pyloric stenosis, or complications of prematurity, such as necrotizing enterocolitis, spontaneous intestinal perforation, and retinopathy of prematurity that require surgical treatment. Options for treatment of postoperative pain include opioids, non-pharmacological interventions, and other drugs. Morphine, fentanyl, and remifentanil are the opioids most often used in neonates. However, negative impact of opioids on the structure and function of the developing brain has been reported. The assessment of the effects of opioids is of utmost importance, especially for neonates in substantial pain during the postoperative period.

OBJECTIVES

To evaluate the benefits and harms of systemic opioid analgesics in neonates who underwent surgery on all-cause mortality, pain, and significant neurodevelopmental disability compared to no intervention, placebo, non-pharmacological interventions, different types of opioids, or other drugs.

SEARCH METHODS

We searched Cochrane CENTRAL, MEDLINE via PubMed and CINAHL in May 2021. We searched the WHO ICTRP, clinicaltrials.gov, and ICTRP trial registries. We searched conference proceedings, and the reference lists of retrieved articles for RCTs and quasi-RCTs.  SELECTION CRITERIA: We included randomized controlled trials (RCTs) conducted in preterm and term infants of a postmenstrual age up to 46 weeks and 0 days with postoperative pain where systemic opioids were compared to 1) placebo or no intervention; 2) non-pharmacological interventions; 3) different types of opioids; or 4) other drugs.  DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were pain assessed with validated methods, all-cause mortality during initial hospitalization, major neurodevelopmental disability, and cognitive and educational outcomes in children more than five years old. We used the fixed-effect model with risk ratio (RR) and risk difference (RD) for dichotomous data and mean difference (MD) for continuous data. We used GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

We included four RCTs enrolling 331 infants in four countries across different continents. Most studies considered patients undergoing large or medium surgical procedures (including major thoracic or abdominal surgery), who potentially required pain control through opioid administration after surgery. The randomized trials did not consider patients undergoing minor surgery (including inguinal hernia repair) and those individuals exposed to opioids before the beginning of the trial. Two RCTs compared opioids with placebo; one fentanyl with tramadol; and one morphine with paracetamol. No meta-analyses could be performed because the included RCTs reported no more than three outcomes within the prespecified comparisons. Certainty of the evidence was very low for all outcomes due to imprecision of the estimates (downgrade by two levels) and study limitations (downgrade by one level).  Comparison 1: opioids versus no treatment or placebo Two trials were included in this comparison, comparing either tramadol or tapentadol with placebo. No data were reported on the following critical outcomes: pain; major neurodevelopmental disability; or cognitive and educational outcomes in children more than five years old. The evidence is very uncertain about the effect of tramadol compared with placebo on all-cause mortality during initial hospitalization (RR 0.32, 95% Confidence Interval (CI) 0.01 to 7.70; RD -0.03, 95% CI -0.10 to 0.05, 71 participants, 1 study; I² = not applicable). No data were reported on: retinopathy of prematurity; or intraventricular hemorrhage.  Comparison 2: opioids versus non-pharmacological interventions No trials were included in this comparison. Comparison 3: head-to-head comparisons of different opioids One trial comparing fentanyl with tramadol was included in this comparison. No data were reported on the following critical outcomes: pain; major neurodevelopmental disability; or cognitive and educational outcomes in children more than five years old. The evidence is very uncertain about the effect of fentanyl compared with tramadol on all-cause mortality during initial hospitalization (RR 0.99, 95% CI 0.59 to 1.64; RD 0.00, 95% CI -0.13 to 0.13, 171 participants, 1 study; I² = not applicable). No data were reported on: retinopathy of prematurity; or intraventricular hemorrhage.  Comparison 4: opioids versus other analgesics and sedatives One trial comparing morphine with paracetamol was included in this comparison. The evidence is very uncertain about the effect of morphine compared with paracetamol on COMFORT pain scores (MD 0.10, 95% CI -0.85 to 1.05; 71 participants, 1 study; I² = not applicable).  No data were reported on the other critical outcomes, i.e. major neurodevelopmental disability; cognitive and educational outcomes in children more than five years old, all-cause mortality during initial hospitalization; retinopathy of prematurity; or intraventricular hemorrhage.

AUTHORS' CONCLUSIONS

Limited evidence is available on opioid administration for postoperative pain in newborn infants compared to either placebo, other opioids, or paracetamol. We are uncertain whether tramadol reduces mortality compared to placebo; none of the studies reported pain scores, major neurodevelopmental disability, cognitive and educational outcomes in children older than five years old, retinopathy of prematurity, or intraventricular hemorrhage. We are uncertain whether fentanyl reduces mortality compared to tramadol; none of the studies reported pain scores, major neurodevelopmental disability, cognitive and educational outcomes in children older than five years old, retinopathy of prematurity, or intraventricular hemorrhage. We are uncertain whether morphine reduces pain compared to paracetamol; none of the studies reported major neurodevelopmental disability, cognitive and educational outcomes in children more than five years old, all-cause mortality during initial hospitalization, retinopathy of prematurity, or intraventricular hemorrhage. We identified no studies comparing opioids versus non-pharmacological interventions.

CUIDADOS CENTRADOS NO DESENVOLVIMENTO DO RECÉM-NASCIDO PREMATURO: ESTUDO SOBRE AS PRÁTICAS EM UNIDADES NEONATAIS PORTUGUESAS

RESUMO Objetivo: analisar a frequência da aplicação das medidas centrais dos cuidados desenvolvimentais ao recém-nascido prematuro em unidades de cuidados neonatais portuguesas e identificar a sua relação com variáveis organizacionais. Método: estudo transversal, descritivo-correlacional. Utilizando técnica de amostragem não probabilística em rede, foi obtida uma amostra de 217 enfermeiros de unidades neonatais portuguesas que responderam online ao questionário Quantum Caring Practice Self-Assessment, traduzido e validado para enfermeiros portugueses. Resultados: os resultados revelaram que para 65,4% dos enfermeiros as práticas de cuidados centrados no desenvolvimento são realizadas às vezes e 14,3% consideram que raramente são realizadas. Somente 18,9% dos enfermeiros inquiridos consideram que essas práticas são realizadas frequentemente. Destacaram-se como práticas mais frequentes, as ligadas ao Ambiente terapêutico e Prevenção da dor e stress. As menos frequentes foram as medidas de Posicionamento e Cuidados à pele. Os resultados demonstraram ainda que a frequência das práticas de cuidados desenvolvimentais difere consoante a localização geográfica das unidades e é mais elevada nas unidades com maior nível de diferenciação de cuidados e que têm instituído um programa/protocolo específico de cuidados desenvolvimentais. Conclusão: as práticas de cuidados centrados no desenvolvimento não são realizadas de forma consistente nas unidades de cuidados neonatais portuguesas, apesar de serem exequíveis. É necessária uma mudança global na cultura das equipas, mais formação, implementação de protocolos e investimento organizacional nesta área.

DEVELOPMENTAL CARE OF PREMATURE NEWBORNS: STUDY ON PRACTICES IN PORTUGUESE NEONATAL UNITS

ABSTRACT Objective: the present and future well-being of hospitalized newborns and their parents are connected to analyze the application frequency of the central practices of developmental care to premature newborns in Portuguese neonatal care units and to identify their relationship with organizational variables. Method: cross-sectional, descriptive-correlational study. Using a non-probabilistic network sampling technique, a sample of 217 nurses from Portuguese neonatal units who answered the Quantum Caring Practice Self-Assessment online questionnaire was obtained, previously translated and validated for Portuguese nurses. Results: the results revealed that for 65.4% of nurses, Developmental Care practices are sometimes performed and 14.3% consider that they are rarely performed. Only 18.9% of the nurses in the study consider that these practices are performed frequently. The most frequent practices were those related to the therapeutic environment and prevention of pain and stress. The least frequent was positioning and skin care. The results also showed that the frequency of developmental care practices differs depending on the geographical location of the units and is higher in units with a higher level of treatment differentiation and that have established a specific program/protocol of developmental care. Conclusion: although feasible, Developmental Care practices are not performed consistently in Portuguese neonatal care units. A global change in team culture, more training, implementation of protocols and organizational investment in this area is needed.

Effect of Kangaroo Care and Oral Sucrose on Pain in Premature Infants: A Randomized Controlled Trial

BACKGROUND

Premature infants hospitalized in the neonatal intensive care unit are routinely exposed to many painful procedures. Pain experienced during the neonatal period may lead to negative outcomes, especially in preterm neonates, hence pain in infants should be reduced. Kangaroo care and oral sucrose are some of the methods that can help reduce pain.

AIM

This study aimed to compare the effects of kangaroo care and oral sucrose on pain relief in preterm infants during heel lancing.

METHODS

Our study involved 64 infants. The infants were randomly divided into two groups using a randomized block design of drawing out slips from a thick, non-transparent envelope. There were 64 slips in this envelope (32 for kangaroo care and 32 for oral sucrose). Kangaroo care was given to the preterm infants in the first group and oral sucrose to those in the second group. In both groups, heart rate and oxygen saturation were measured and pain score was evaluated by two observers using the Premature Infant Pain Profile (PIPP) before, during, and 2 minutes after blood sampling by heel lancing.

RESULTS

There was a statistically significant difference between the groups in favor of the kangaroo group in terms of change in the PIPP values after heel lancing. Kangaroo care is more effective than oral sucrose in pain relief during heel lancing in preterm infants.

CONCLUSIONS

In addition to many benefits it offers to infants, kangaroo care can be used to reduce pain during painful procedures in premature infants.

Analgesics and Sedatives in Critically Ill Newborns and Infants: The Impact on Long-Term Neurodevelopment

Inadequate pain and/or stress management in preterm- and term-born infants has been associated with increased morbidity and even mortality. However, exposure to analgosedatives during early infancy may also be one of the risk factors for subsequent neurodevelopmental impairment, at least in animal studies. Because infants admitted to neonatal or pediatric intensive care units may receive high amounts of these drugs for prolonged periods of time and the majority of these infants nowadays survive to discharge, this is of major concern. A balanced approach that incorporates the assessment and quantification of both wanted effects as well as unwanted side effects is therefore needed. In this article, the optimal dose determination of commonly used analgosedative drugs as well as their potential long-term effects on the developing human brain and neuropsychological functioning are reviewed.

Postsurgery analgesic and sedative drug use in a French neonatal intensive care unit: A single-center retrospective cohort study

OBJECTIVE

To describe pain assessment, the pattern of analgesic and sedative drug use, and adverse drug reactions in a neonatal intensive care unit (NICU) during the postsurgery phase.

METHOD

Demographic characteristics, pain scores, and drug use were extracted and analyzed from electronic patient medical files for infants after surgery, admitted consecutively between January 2012 and June 2013.

RESULT

One hundred and sixty-eight infants were included. Acute (DAN score) and prolonged (EDIN score) pain assessment scores were used in 79% and 64% of infants, respectively, on the 1st day. This percentage decreased over the 7 days following surgery. The weekly average scores postsurgery were 2/15 (±2.2) for the EDIN score and 1.6/10 (±2.0) for the DAN score. The rates of pain control were 88% for the EDIN and 72% for the DAN. The most prescribed opiate drug was fentanyl (98 patients; 58%) with an average dose of 1.8 (±0.6) μg/kg/h. Midazolam was used in 95 patients (56%), with an average dose of 35 (±14) μg/kg/h. A bolus was administered in 7% (±7.4) of the total dose for fentanyl and 8% (±9.3) for midazolam. Similar doses were used in term and preterm neonates. Of 118 patients receiving fentanyl and/or midazolam, 40% presented urinary retention, 28% a weaning syndrome. Paracetamol (155 patients; 92%) and nalbuphine (55 patients; 33%) were the other medications most often prescribed.

CONCLUSION

The off-label use of fentanyl and midazolam was necessary to treat pain after surgery. Pain assessment should be conducted for all neonates in order to optimize their treatment. Research on analgesic and sedative medicine in vulnerable neonates seems necessary to standardize practices and reduce adverse drug reactions.

The research gap in chronic paediatric pain: A systematic review of randomised controlled trials

BACKGROUND AND OBJECTIVE

Chronic pain is associated with significant functional and social impairment. The objective of this review was to assess the characteristics and quality of randomized controlled trials (RCTs) evaluating pain management interventions in children and adolescents with chronic pain.

METHODS

We performed a systematic search of PubMed, Embase and the Cochrane Library up to July 2017. We included RCTs that involved children and adolescents (3 months-18 years) and evaluated the use of pharmacological or non-pharmacological intervention(s) in the context of pain persisting or re-occurring for more than 3 months. Methodological quality was evaluated using the Cochrane Risk of Bias (ROB) Tool.

RESULTS

A total of 58 RCTs were identified and numbers steadily increased over time. The majority were conducted in single hospital institutions, with no information on study funding. Median sample size was 47.5 participants (Q1,Q3: 32, 70). Forty-five percent of RCTs included both adults and children and the median of the mean ages at inclusion was 12.9 years (Q1,Q3: 11, 15). Testing of non-pharmacological interventions was predominant and only 5 RCTs evaluated analgesics or co-analgesics. Abdominal pain, headache/migraine and musculoskeletal pain were the most common types of chronic pain among participants. Methodological quality was poor with 90% of RCTs presenting a high or unclear ROB.

CONCLUSIONS

Evaluation of analgesics targeting chronic pain relief in children and adolescents through RCTs is marginal. Infants and children with long-lasting painful conditions are insufficiently represented in RCTs. We discuss possible research constraints and challenges as well as methodologies to circumvent them.

SIGNIFICANCE

There is a substantial research gap regarding analgesic interventions for children and adolescents with chronic pain. Most clinical trials in the field focus on the evaluation of non-pharmacological interventions and are of low methodological quality. There is also a specific lack of trials involving infants and children and adolescents with long-lasting diseases.

Neonatal Maturation of Paracetamol (Acetaminophen) Glucuronidation, Sulfation, and Oxidation Based on a Parent-Metabolite Population Pharmacokinetic Model

OBJECTIVES

This study aimed to model the population pharmacokinetics of intravenous paracetamol and its major metabolites in neonates and to identify influential patient characteristics, especially those affecting the formation clearance (CL_formation) of oxidative pathway metabolites.

METHODS

Neonates with a clinical indication for intravenous analgesia received five 15-mg/kg doses of paracetamol at 12-h intervals (<28 weeks' gestation) or seven 15-mg/kg doses at 8-h intervals (≥28 weeks' gestation). Plasma and urine were sampled throughout the 72-h study period. Concentration-time data for paracetamol, paracetamol-glucuronide, paracetamol-sulfate, and the combined oxidative pathway metabolites (paracetamol-cysteine and paracetamol-N-acetylcysteine) were simultaneously modeled in NONMEM 7.2.

RESULTS

The model incorporated 259 plasma and 350 urine samples from 35 neonates with a mean gestational age of 33.6 weeks (standard deviation 6.6). CL_formation for all metabolites increased with weight; CL_formation for glucuronidation and oxidation also increased with postnatal age. At the mean weight (2.3 kg) and postnatal age (7.5 days), CL_formation estimates (bootstrap 95% confidence interval; between-subject variability) were 0.049 L/h (0.038-0.062; 62 %) for glucuronidation, 0.21 L/h (0.17-0.24; 33 %) for sulfation, and 0.058 L/h (0.044-0.078; 72 %) for oxidation. Expression of individual oxidation CL_formation as a fraction of total individual paracetamol clearance showed that, on average, fractional oxidation CL_formation increased <15 % when plotted against weight or postnatal age.

CONCLUSIONS

The parent-metabolite model successfully characterized the pharmacokinetics of intravenous paracetamol and its metabolites in neonates. Maturational changes in the fraction of paracetamol undergoing oxidation were small relative to between-subject variability.

Neonatal pain management: still in search for the Holy Grail

Inadequate pain management but also inappropriate use of analgesics in early infancy has negative effects on neurodevelopmental outcome. As a consequence, neonatal pain management is still in search for the Holy Grail. At best, effective pain management is based on prevention, assessment, and treatment followed by a re-assessment of the pain to determine if additional treatment is still necessary. Unfortunately, epidemiological observations suggest that neonates are undergoing painful procedures very frequently, unveiling the need for effective preventive, non-pharmacological strategies. In addition, assessment is still based on validated, multimodal, but subjective pain assessment tools. Finally, in neonatal intensive care units, there is a shift in clinical practices (e.g., shorter intubation and ventilation), and this necessitates the development and validation of new pharmacological treatment modalities. To illustrate this, a shift in the use of opioids to paracetamol has occurred and short-acting agents (remifentanil, propofol) are more commonly administered to neonates. In addition to these new modalities and as part of a more advanced approach of the developmental pharmacology of analgesics, pharmacogenetics also emerged as a tool for precision medicine in neonates. To assure further improvement of neonatal pain management the integration of pharmacogenetics with the usual covariates like weight, age and/or disease characteristics is needed.

Neonatal paracetamol treatment reduces long-term nociceptive behaviour after neonatal procedural pain in rats

BACKGROUND

Pain from skin penetrating procedures (procedural pain) during infancy in the neonatal intensive care unit (NICU) may result in changes of nociceptive sensitivity in later life. This supports the need for pain management during such vulnerable periods in life. This study, therefore, analyses the short- and long-term consequences of neonatal paracetamol (acetaminophen) treatment on pain behaviour in an experimental rat model of neonatal procedural pain.

METHODS

A repetitive needle-prick model was used, in which neonatal rats received four needle pricks into the left hind paw per day from postnatal day 0 to day 7 (P0-P7). Paracetamol (50 mg/kg/day s.c.) was administered daily (P0-P7), and sensitivity to mechanical stimuli was compared with a needle-prick/saline-treated group and to a tactile control group. At 8 weeks of age, all animals underwent an ipsilateral paw-incision, modelling postoperative pain, and the duration of hypersensitivity was assessed.

RESULTS

Neonatal paracetamol administration had no effect upon short-term mechanical hypersensitivity during the first postnatal week or upon long-term baseline sensitivity from 3 to 8 weeks. However, neonatal paracetamol administration significantly reduced the postoperative mechanical hypersensitivity in young adults, caused by repetitive needle pricking.

CONCLUSION

Paracetamol administration during neonatal procedural pain does not alter short-term or long-term effects on mechanical sensitivity, but does reduce the duration of increased postoperative mechanical hypersensitivity in a clinically relevant neonatal procedural pain model.

WHAT DOES THIS STUDY ADD

Paracetamol can be used safely in neonatal rats. Neonatal paracetamol treatment had no effect upon short-term mechanical hypersensitivity during the first postnatal week, nor upon long-term baseline sensitivity from 3 to 8 weeks. Paracetamol treatment during the first postnatal week significantly reduced the postoperative mechanical hypersensitivity in young adult rats.

Population Pharmacokinetics of Intravenous Paracetamol (Acetaminophen) in Preterm and Term Neonates: Model Development and External Evaluation

OBJECTIVES

The aims of this study were to develop a population pharmacokinetic model for intravenous paracetamol in preterm and term neonates and to assess the generalizability of the model by testing its predictive performance in an external dataset.

METHODS

Nonlinear mixed-effects models were constructed from paracetamol concentration-time data in NONMEM 7.2. Potential covariates included body weight, gestational age, postnatal age, postmenstrual age, sex, race, total bilirubin, and estimated glomerular filtration rate. An external dataset was used to test the predictive performance of the model through calculation of bias, precision, and normalized prediction distribution errors.

RESULTS

The model-building dataset included 260 observations from 35 neonates with a mean gestational age of 33.6 weeks [standard deviation (SD) 6.6]. Data were well-described by a one-compartment model with first-order elimination. Weight predicted paracetamol clearance and volume of distribution, which were estimated as 0.348 L/h (5.5 % relative standard error; 30.8 % coefficient of variation) and 2.46 L (3.5 % relative standard error; 14.3 % coefficient of variation), respectively, at the mean subject weight of 2.30 kg. An external evaluation was performed on an independent dataset that included 436 observations from 60 neonates with a mean gestational age of 35.6 weeks (SD 4.3). The median prediction error was 10.1 % [95 % confidence interval (CI) 6.1-14.3] and the median absolute prediction error was 25.3 % (95 % CI 23.1-28.1).

CONCLUSIONS

Weight predicted intravenous paracetamol pharmacokinetics in neonates ranging from extreme preterm to full-term gestational status. External evaluation suggested that these findings should be generalizable to other similar patient populations.

Effect of UGT2B7 -900G>A (-842G>A; rs7438135) on morphine glucuronidation in preterm newborns: results from a pilot cohort

AIM

Assess association between UGT2B7 polymorphism -900G>A (rs7438135, also known as -842G>A) with morphine kinetics in preterm newborns undergoing mechanical ventilation.

MATERIALS & METHODS

Thirty-four infants were enrolled in a randomized clinical trial and allocated to rapid sequence intubation with remifentanil (1 µg/kg) or morphine (0.3 mg/kg). The latter group was included in our study.

RESULTS

Morphine plasma concentrations at 20 min post intubation were associated with postnatal age (p=0.017) and UGT2B7 -900G>A (p=0.036). UGT2B7 -900A allele carriers (n=13) had lower morphine levels compared with UGT2B7 -900G/G patients (n=2). Morphine-3-glucuronide and morphine-6-glucuronide plasma concentrations were only found to be associated with gestational and postnatal age. However, -900A allele carriers had a higher morphine-3-glucuronide:morphine metabolic ratio compared with patients genotyped as -900G/G (p=0.005), as determined by linear regression.

CONCLUSION

Our small pilot study illustrates that in addition to gestational and postnatal age, the UGT2B7 -900G>A polymorphism significantly alters morphine pharmacokinetics in preterm infants.

Sucrose-induced analgesia during early life modulates adulthood learning and memory formation

This study is aimed at examining the long-term effects of chronic pain during early life (postnatal day 0 to 8weeks), and intervention using sucrose, on cognitive functions during adulthood in rats. Pain was induced in rat pups via needle pricks of the paws. Sucrose solution or paracetamol was administered for analgesia before the paw prick. Control groups include tactile stimulation to account for handling and touching the paws, and sucrose alone was used. All treatments were started on day one of birth and continued for 8weeks. At the end of the treatments, behavioral studies were conducted to test the spatial learning and memory using radial arm water maze (RAWM), as well as pain threshold via foot-withdrawal response to a hot plate apparatus. Additionally, the hippocampus was dissected, and blood was collected. Levels of neurotrophins (BDNF, IGF-1 and NT-3) and endorphins were assessed using ELISA. The results show that chronic noxious stimulation resulted in comparable foot-withdrawal latency between noxious and tactile groups. On the other hand, pretreatment with sucrose or paracetamol increased pain threshold significantly both in naive rats and noxiously stimulated rats (P<0.05). Chronic pain during early life impaired short-term memory, and sucrose treatment prevented such impairment (P<0.05). Sucrose significantly increased serum levels of endorphin and enkephalin. Chronic pain decreased levels of BDNF in the hippocampus and this decrease was prevented by sucrose and paracetamol treatments. Hippocampal levels of NT-3 and IGF-1 were not affected by any treatment. In conclusion, chronic pain induction during early life induced short memory impairment, and pretreatment with sucrose prevented this impairment via mechanisms that seem to involve BDNF. As evident in the results, sucrose, whether alone or in the presence of pre-noxious stimulation, increases pain threshold in such circumstances; most likely via a mechanism that involves an increase in endogenous opioids.

The addition of tramadol to the standard of i.v. acetaminophen and morphine infusion for postoperative analgesia in neonates offers no clinical benefit: a randomized placebo-controlled trial

BACKGROUND

Tramadol is used following neonatal cardiac and general surgery. However, its ability to opioid-spare or facilitate earlier extubation in postoperative neonates is unquantified.

OBJECTIVE

This randomized placebo-controlled trial aimed to assess whether tramadol's addition to standard analgesia resulted in earlier extubation or reduced analgesic/sedative requirements in postsurgical neonates.

METHODS

Neonates born ≥32 weeks postmenstrual age received either tramadol [T] 2 mg·kg(-1) or placebo [P] 6-hourly for up to 5 days postthoracoabdominal surgery in addition to morphine (commenced at 20 mcg·kg(-1) ·h(-1)) and 6-hourly i.v. acetaminophen. Time to extubation, morphine and midazolam amounts, hourly pain scores, and seizure activity were compared using an intention-to-treat and per-protocol analysis.

RESULTS

Seventy-one neonates participated. Median survival time to extubation was similar between the groups (T 67 h [95% CI 51, 84] vs P 52 h [95%CI 43, 65]; P = 0.4), and similar numbers were extubated by 96 h (T 69% vs P 77%; difference -8%, 95%CI -28, 13%). Morphine and midazolam exposure was similar, with low pain scores in both groups (mean percentage of time with a pain score >5/20 during the 5 days: T 13% vs P 11%, difference in means 2.8 [95% CI -1.8, 7.6], P = 0.20). Most participants had normal cranial ultrasounds (T 86% vs P 86%); no seizures occurred clinically or electroencephalographically.

CONCLUSION

Tramadol's addition to standard analgesia in this small group of postsurgical neonates did not appear to have any positive effect on time to extubation, morphine or midazolam exposure, or pain scores. This questions the benefit of tramadol for postsurgical neonates. Importantly, no seizures occurred in these ill neonates who may potentially be at greater risk of tramadol toxicity compared with adults.

The postoperative management of pain from intracranial surgery in pediatric neurosurgical patients

Pain following intracranial surgery has historically been undertreated because of the concern that opioids, the analgesics most commonly used to treat moderate-to-severe pain, will interfere with the neurologic examination and adversely affect postoperative outcome. Over the past decade, accumulating evidence, primarily in adult patients, has revealed that moderate-to-severe pain is common in neurosurgical patients following surgery. Using the neurophysiology of pain as a blueprint, we have highlighted some of the drugs and drug families used in multimodal pain management. This analgesic method minimizes opioid-induced adverse side effects by maximizing pain control with smaller doses of opioids supplemented with neural blockade and nonopioid analgesics, such nonsteroidal antiinflammatory drugs, local anesthetics, corticosteroids, N-methyl-D-aspartate (NMDA) antagonists, α2 -adrenergic agonists, and/or anticonvulsants (gabapentin and pregabalin).

Neonatal pain

Effective management of procedural and postoperative pain in neonates is required to minimize acute physiological and behavioral distress and may also improve acute and long-term outcomes. Painful stimuli activate nociceptive pathways, from the periphery to the cortex, in neonates and behavioral responses form the basis for validated pain assessment tools. However, there is an increasing awareness of the need to not only reduce acute behavioral responses to pain in neonates, but also to protect the developing nervous system from persistent sensitization of pain pathways and potential damaging effects of altered neural activity on central nervous system development. Analgesic requirements are influenced by age-related changes in both pharmacokinetic and pharmacodynamic response, and increasing data are available to guide safe and effective dosing with opioids and paracetamol. Regional analgesic techniques provide effective perioperative analgesia, but higher complication rates in neonates emphasize the importance of monitoring and choice of the most appropriate drug and dose. There have been significant improvements in the understanding and management of neonatal pain, but additional research evidence will further reduce the need to extrapolate data from older age groups. Translation into improved clinical care will continue to depend on an integrated approach to implementation that encompasses assessment and titration against individual response, education and training, and audit and feedback.

Use of analgesic and sedative drugs in VLBW infants in German NICUs from 2003-2010

Very low birth weight (VLBW) infants frequently receive analgesia and/or sedation for painful procedures and mechanical ventilation to avoid negative stress. Yet, concerns remain regarding potential adverse long-term effects of these drugs on VLBW infants' neurocognitive outcome. Recent studies have shown that less invasive surfactant application (LISA) and early nasal CPAP treatment reduce the need for mechanical ventilation and painful procedures. Therefore, these measures might also reduce the application of analgesic and/or sedative drugs in VLBW infants. To evaluate this hypothesis and to identify potential changes in analgesic treatment concepts in recent years, we retrospectively analyzed data on analgesia and sedation, respiratory support, and the method of surfactant application in VLBW infants enrolled in the German Neonatal Network (GNN) trial between 2003 and 2009 (period 1) and compared it with data from infants participating in GNN in 2010 (period 2). In both periods, about one third of all infants were treated with analgesic and/or sedative drugs using a wide variety of substances. The administration of novel drugs such as propofol, sufentanil, or intravenous paracetamol was higher in 2010 (6.7 vs. 12.2 %). Infants who were treated with CPAP only received significantly less analgesic/sedative medication than infants who were mechanically ventilated (12 vs. 65 %, p=<0.001). Similarly, infants treated with LISA received less analgesic or sedative drugs as compared to infants who received surfactant via endotracheal intubation (36 vs. 63 %, p=0.001).

CONCLUSION

Although both avoidances of mechanical ventilation and less invasive surfactant application are associated with reduced analgesic or sedative treatment, the percentage of VLBW infants who received analgesia and/or sedation remained unchanged in Germany in recent years.