Oral glucose before venepuncture relieves neonates of pain, but stress is still evidenced by increase in oxygen consumption, energy expenditure, and heart rate

Biomarkers for assessing pain and pain relief in the neonatal intensive care unit

Newborns admitted to the neonatal intensive care unit (NICU) regularly undergo painful procedures and may face various painful conditions such as postoperative pain. Optimal management of pain in these vulnerable preterm and term born neonates is crucial to ensure their comfort and prevent negative consequences of neonatal pain. This entails accurate and timely identification of pain, non-pharmacological pain treatment and if needed administration of analgesic therapy, evaluation of treatment effectiveness, and monitoring of adverse effects. Despite the widely recognized importance of pain management, pain assessment in neonates has thus far proven to be a challenge. As self-report, the gold standard for pain assessment, is not possible in neonates, other methods are needed. Several observational pain scales have been developed, but these often rely on snapshot and largely subjective observations and may fail to capture pain in certain conditions. Incorporation of biomarkers alongside observational pain scores holds promise in enhancing pain assessment and, by extension, optimizing pain treatment and neonatal outcomes. This review explores the possibilities of integrating biomarkers in pain assessment in the NICU.

Oxidative Stress in Preterm Newborns

Preterm babies are highly susceptible to oxidative stress (OS) due to an imbalance between the oxidant and antioxidant systems. The generation of free radicals (FR) induces oxidative damage to multiple body organs and systems. OS is the main factor responsible for the development of typical premature infant diseases, such as bronchopulmonary dysplasia, retinopathy of prematurity, necrotizing enterocolitis, intraventricular hemorrhage, periventricular leukomalacia, kidney damage, eryptosis, and also respiratory distress syndrome and patent ductus arteriosus. Many biomarkers have been detected to early identify newborns at risk of developing a free radical-mediated disease and to investigate new antioxidant strategies. This review reports the current knowledge on OS in the preterm newborns and the newest findings concerning the use of OS biomarkers as diagnostic tools, as well as in implementing antioxidant therapeutic strategies for the prevention and treatment of these diseases and their sequelae.

Development of locally relevant clinical guidelines for procedure-related neonatal analgesic practice in Kenya: a systematic review and meta-analysis

Background Increasing numbers of neonates are undergoing painful procedures in low-income and middle-income countries, with adequate analgesia seldom used. In collaboration with a multi-disciplinary team in Kenya, we aimed to establish the first evidence-based guidelines for the management of routine procedure-related neonatal pain that consider low-resource hospital settings.

METHODS

We did a systematic review by searching MEDLINE, Embase, CINAHL, and CENTRAL databases for studies published from Jan 1, 1953, to March 31, 2019. We included data from randomised controlled trials using heart rate, oxygen saturation (SpO2), premature infant pain profile (PIPP) score, neonatal infant pain scale (NIPS) score, neonatal facial coding system score, and douleur aiguë du nouveau-né scale score as pain outcome measures. We excluded studies in which neonates were undergoing circumcision or were intubated, studies from which data were unextractable, or when pain was scored by non-trained individuals. We did a narrative synthesis of all studies, and meta-analysis when data were available from multiple studies comparing the same analgesics and controls and using the same outcome measures. 17 Kenyan health-care professionals formed our clinical guideline development panel, and we used the Grading of Recommendations, Assessment, Development and Evaluation framework and the panel's knowledge of the local health-care context to guide the guideline development process. This study is registered with PROSPERO, CRD42019126620.

FINDINGS

Of 2782 studies assessed for eligibility, data from 149 (5%) were analysed, with 80 (3%) of these further contributing to our meta-analysis. We found a high level of certainty for the superiority of breastfeeding over placebo or no intervention (standardised mean differences [SMDs] were -1·40 [95% CI -1·96 to -0·84] in PIPP score and -2·20 [-2·91 to -1·48] in NIPS score), and the superiority of oral sugar solutions over placebo or no intervention (SMDs were -0·38 [-0·61 to -0·16] in heart rate and 0·23 [0·04 to 0·42] in SpO2). We found a moderate level of certainty for the superiority for expressed breastmilk over placebo or no intervention (SMDs were -0·46 [95% CI -0·87 to -0·05] in heart rate and 0·48 [0·20 to 0·75] in SpO2). Therefore, the panel recommended that breastfeeding should be given as first-line analgesic treatment, initiated at least 2 min pre-procedure. Given contextual factors, for neonates who are unable to breastfeed, 1-2 mL of expressed breastmilk should be given as first-line analgesic, or 1-2 mL of oral sugar (≥10% concentration) as second-line analgesic. The panel also recommended parental presence during procedures with adjunctive provision of skin-to-skin care, or non-nutritive sucking when possible.

INTERPRETATION

We have generated Kenya's first neonatal analgesic guidelines for routine procedures, which have been adopted by the Kenyan Ministry of Health, and have shown a framework for clinical guideline development that is applicable to other low-income and middle-income health-care settings.

FUNDING

Wellcome Trust Research Programme, and the Africa-Oxford Initiative.

The influence of pain, agitation, and their management on the immature brain

Preterm infants are exposed to frequent painful procedures and agitating stimuli over the many weeks of their hospitalization in the neonatal intensive care unit (NICU). The adverse neurobiological impact of pain and stress in the preterm infant has been well documented, including neuroimaging and neurobehavioral outcomes. Although many tools have been validated to assess acute pain, few methods are available to assess chronic pain or agitation (a clinical manifestation of neonatal stress). Both nonpharmacologic and pharmacologic approaches are used to reduce the negative impact of pain and agitation in the preterm infant, with concerns emerging over the adverse effects of analgesia and sedatives. Considering benefits and risks of available treatments, units must develop a stepwise algorithm to prevent, assess, and treat pain. Nonpharmacologic interventions should be consistently utilized prior to mild to moderately painful procedures. Sucrose may be utilized judiciously as an adjunctive therapy for minor painful procedures. Rapidly acting opioids (fentanyl or remifentanil) form the backbone of analgesia for moderately painful procedures. Chronic sedation during invasive mechanical ventilation represents an ongoing challenge; appropriate containment and an optimal environment should be standard; when indicated, low-dose morphine infusion may be utilized cautiously and dexmedetomidine infusion may be considered as an emerging adjunct.

Nociceptive Cortical Activity Is Dissociated from Nociceptive Behavior in Newborn Human Infants under Stress

Newborn infants display strong nociceptive behavior in response to tissue damaging stimuli, and this is accompanied by nociceptive activity generated in subcortical and cortical areas of the brain [1, 2]. In the absence of verbal report, these nociceptive responses are used as measures of pain sensation in newborn humans, as they are in animals [3, 4]. However, many infants are raised in a physiologically stressful environment, and little is known about the effect of background levels of stress upon their pain responses. In adults, acute physiological stress causes hyperalgesia [5, 6, 7], and increased background stress increases pain [8, 9, 10], but these data cannot necessarily be extrapolated to infants. Here we have simultaneously measured nociceptive behavior, brain activity, and levels of physiological stress in a sample of 56 newborn human infants aged 36–42 weeks. Salivary cortisol (hypothalamic pituitary axis), heart rate variability (sympathetic adrenal medullary system), EEG event-related potentials (nociceptive cortical activity), and facial expression (behavior) were acquired in individual infants following a clinically required heel lance. We show that infants with higher levels of stress exhibit larger amplitude cortical nociceptive responses, but this is not reflected in their behavior. Furthermore, while nociceptive behavior and cortical activity are normally correlated, this relationship is disrupted in infants with high levels of physiological stress. Brain activity evoked by noxious stimulation is therefore enhanced by stress, but this cannot be deduced from observation of pain behavior. This may be important in the prevention of adverse effects of early repetitive pain on brain development.

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Infant pain behavior and nociceptive brain activity are generally correlated

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Stress disrupts the relationship between infant pain brain activity and behavior

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Stress is associated with increased nociceptive brain activity, but not behavior

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Stress is an important factor when assessing infant pain experience

Oral glucose efficacy on neonate's pain responses at the NICU: A quasi experimental trial of two clinical procedures

AIM

This research was undertaken with the purpose of testing two research hypotheses regarding the efficacy of 10% oral glucose solution on procedural pain associated with venepuncture and nasopharyngeal suctioning within three neonatal intensive care units (NICU). The hypotheses were formulated from previous conclusions reached by other researchers highlighting the efficacy of sucrose solutions on neonates' pain responses during minor painful procedures.

METHOD

A quasi-experimental trial utilising a time series design with one group was used. Data from a total of 90 neonates included 60 neonates who underwent a venepuncture and 30 neonates who underwent a nasopharyngeal suctioning procedure for clinical purposes. The neonate's pain response for each procedure was scored using the Neonatal Pain Assessment Scale (NPAS) on two separate occasions over three time periods. The pre-procedural score (T₀) when the neonate received no sucrose, the inter-procedural score (T₁) when the neonate was given 2ml of 10% glucose solution two minutes before the procedure (intervention group) or where oral glucose was withheld (control group) and the post-procedural score (T₂) being at the end of the procedure.

RESULTS

The results showed the mean NPAS scores in response to venepuncture or nasopharyngeal suctioning were significantly lower in the intervention group than the control group.

CONCLUSION

This showed that oral glucose (10%) had a positive effect on the pain response during venepuncture and nasopharyngeal suctioning procedures.

The validity and reliability of the EValuation of INtervention Scale: preliminary report

AIM

Pain management is a priority for infants receiving neonatal care as they undergo many necessary painful and stressful interventions, which are associated with negative short- or long-term consequences. This study aims to validate the content, and test the reliability, of the EValuation of INtervention Scale (EVIN), which is designed to evaluate the use of widely recommended nonpharmacological strategies to reduce neonatal pain and stress during procedures.

METHODS

The content of the EVIN was validated with multidisciplinary participation (N = 80), and consistency was established via observations on preterm infants (N = 12, at 31-34 weeks' gestation) during interventions in a neonatal unit. A revised scale was tested for inter-rater reliability with observations of invasive (blood sampling, N = 16) and noninvasive (nappy change, N = 18) interventions. The intraclass correlation coefficient (ICC) was used to determine inter-rater reliability. SPSS (PASW Statistics) version 18 was used for analysis.

RESULTS

Very good intraclass correlation coefficients (>0.8) for both invasive (0.962) and noninvasive procedures (0.970) were achieved.

CONCLUSION

These results indicate that the EVIN is suitable for the evaluation of nonpharmacological support during painful or stressful interventions.

Oral glucose solution to alleviate pain induced by intramuscular injections in preterm infants

PURPOSE

The purpose was to assess the effectiveness of 5% oral glucose solution in reducing pain in preterm infants during intramuscular injection.

DESIGN AND METHODS

We conducted a prospective, randomized, controlled, unblinded trial to investigate the effect of glucose solution on the pain of intramuscular injection in preterm infants (N = 80).

RESULTS

Infants who received oral glucose had significantly lower pain scores (p < .001), less crying time (p < .001), higher oxygen saturation (p < .001), and lower heart rate after compared with during the procedure (p = .02).

PRACTICE IMPLICATIONS

Our results suggest that oral glucose, even if used in the lowest dose, may have a pain-relieving effect in preterm infants if administered pre-procedure.

Cerebral hemodynamic changes and pain perception during venipuncture: is glucose really effective?

Newborns are exposed to a considerable number of painful stimuli. This study is aimed to investigate the effects of 30% glucose solution and nonnutritive sucking on pain perception during venipuncture. Twenty-five term infants were randomized as receiving 30% dextrose (group 1) or sterile water (group 2). Neonatal Infant Pain Scale scores, skin conductance algesimeter recordings, and near-infrared spectroscopy measurements were recorded during the procedure. Neonatal Infant Pain Scale and skin conductance algesimeter results were decreased in both groups from that during venipuncture to after the procedure. Group 1 had lower Neonatal Infant Pain Scale scores compared with group 2 after venipuncture, different from the skin conductance algesimeter, where no difference was observed between groups. In group 1, cerebral blood volume increased after venipuncture. Glucose does not attenuate the Neonatal Infant Pain Scale score and skin conductance algesimeter index during venipuncture, but it leads to a lower Neonatal Infant Pain Scale score after venipuncture unlike the skin conductance algesimeter index, which was not lowered.

A systematic review and meta-analyses of nonsucrose sweet solutions for pain relief in neonates

BACKGROUND

Sucrose has been demonstrated to provide analgesia for minor painful procedures in infants. However, results of trials investigating other sweet solutions for neonatal pain relief have not yet been synthesized.

OBJECTIVE

To establish the efficacy of nonsucrose sweet-tasting solutions for pain relief during painful procedures in neonates.

METHOD

The present article is a systematic review and meta-analyses of the literature. Standard methods of the Cochrane Neonatal Collaborative Review Group were used. Literature searches were reviewed for randomized controlled trials investigating the use of sweet solutions, except sucrose, for procedural pain management in neonates. Outcomes assessed included validated pain measures and behavioural and physiological indicators.

RESULTS

Thirty-eight studies (3785 neonates) were included, 35 of which investigated glucose. Heel lancing was performed in 21⁄38 studies and venipuncture in 11⁄38 studies. A 3.6-point reduction in Premature Infant Pain Profile scores during heel lances was observed in studies comparing 20% to 30% glucose with no intervention (two studies, 124 neonates; mean difference -3.6 [95% CI -4.6 to -2.6]; P<0.001; I2=54%). A significant reduction in the incidence of cry after venipuncture for infants receiving 25% to 30% glucose versus water or no intervention was observed (three studies, 130 infants; risk difference -0.18 [95% CI -0.31 to -0.05]; P=0.008, number needed to treat = 6 [95% CI 3 to 20]; I2=63%).

CONCLUSIONS

The present systematic review and meta-analyses demonstrate that glucose reduces pain scores and crying during single heel lances and venipunctures. Results indicate that 20% to 30% glucose solutions have analgesic effects and can be recommended as an alternative to sucrose for procedural pain reduction in healthy term and preterm neonates.

Two formulations of epoprostenol sodium in the treatment of pulmonary arterial hypertension: EPITOME-1 (epoprostenol for injection in pulmonary arterial hypertension), a phase IV, open-label, randomized study

BACKGROUND

Epoprostenol sodium with arginine-mannitol excipients (epoprostenol AM; Veletri [Actelion Pharmaceuticals Ltd, Allschwil, Switzerland]) and epoprostenol sodium with glycine-mannitol excipients (epoprostenol GM; Flolan [GlaxoSmithKline, Triangle Park, NC]) are intravenous treatments for pulmonary arterial hypertension (PAH). Epoprostenol AM contains different inactive excipients, resulting in greater stability at room temperature compared with epoprostenol GM.

METHODS

In this prospective, multicenter, open-label, randomized, phase IV exploratory study, epoprostenol-naïve patients in need of injectable prostanoid therapy were randomized 2:1 to open-label epoprostenol AM or epoprostenol GM. The study period was 28 days, followed by a 30-day safety follow-up. Study aims were to descriptively compare the safety, tolerability, drug metabolite levels, and treatment effects of epoprostenol AM and epoprostenol GM in PAH. Statistical analysis was descriptive only because of the exploratory nature of the study.

RESULTS

Thirty patients with PAH (18-70 years, 24 women, 20 idiopathic PAH) were randomized to epoprostenol AM (n = 20) or epoprostenol GM (n = 10). Most frequently reported adverse events included jaw pain, headache, nausea, and flushing. Two deaths occurred during the study period, and 1 death occurred during the 30-day safety follow-up period, all in patients receiving epoprostenol AM. All deaths were classified by the treating physician as unrelated to epoprostenol AM. The median (range) change from baseline to day 28 in 6-minute walk distance was 36 m (-127 to 210 m) and 49 m (-44 to 110 m) for the epoprostenol AM and epoprostenol GM groups, respectively.

CONCLUSIONS

In this randomized clinical study of epoprostenol AM in PAH, use of this novel preparation with greater room temperature stability was well tolerated.

Sweet-tasting solutions for needle-related procedural pain in infants one month to one year of age

BACKGROUND

Administration of oral sucrose or glucose with and without non-nutritive sucking is frequently used as a non-pharmacological intervention for needle-related procedural pain relief in infants.

OBJECTIVES

To determine the effectiveness of sweet-tasting solutions for needle-related procedural pain in infants one month to one year of age compared with no treatment, placebo, other sweet-tasting solutions, or pharmacological or other non-pharmacological pain-relieving methods.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012); MEDLINE via Ovid (1966 to 2012); CINAHL via OVID (1982 to 2012). The World Health Organization International Clinical Trials Registry Platform was also searched for any ongoing trials. Clinical trial registries, conference proceedings and references for randomised controlled trials (RCTs) were also searched. An updated search was run to capture any new publications before finalising the review in April 2012 and no new included studies were identified. Two review authors (MK & JF) independently abstracted data and assessed quality using a standard form. Authors have been contacted for missing data.

SELECTION CRITERIA

Randomised-controlled trials using a sweet-tasting solution to treat pain in healthy term infants (gestational age 37 weeks and over), between one month and 12 months of age who required needle-related procedures. These procedures included but were not limited to: subcutaneous or intramuscular injections, venepuncture, and heel lance. Studies in which the painful procedure was circumcision, lumbar puncture or supra-pubic bladder aspiration were not included as they are more severe and painful than needle-related procedures. Control conditions included no treatment or placebo (water) or any other identical intervention (same appearance and consistency) without active ingredient, another sweet-tasting solution, a pharmacological pain-relieving method (e.g. paracetamol, topical anaesthetic cream), non-pharmacological pain-relieving method (e.g. distraction method, non-nutritive sucking).

DATA COLLECTION AND ANALYSIS

Assessment of trial quality, data extraction and synthesis of data were performed using standard methods of the Cochrane Pain, Palliative and Supportive Care Group. We report mean differences (MD) with 95% confidence intervals (CI) using fixed-effect models as appropriate for continuous outcome measures. We planned to report risk ratio (RR) and risk difference (RD) for dichotomous outcomes. The Chi(2) test and I(2) statistic were used to assess between-study heterogeneity.

MAIN RESULTS

Sixty-five (65) studies were identified for possible inclusion in this review. Fourteen published RCTs with a total of 1551 participants met the inclusion criteria. Duration of cry was significantly reduced in infants who were administered a sweet-tasting solution [MD -13.47 (95% CI -16.80 to -10.15)], P < 0.00001 compared with water. However, there was considerable heterogeneity between the studies (I(2) = 94%) that we were unable to explain. Meta-analysis was not able to be undertaken for any of the other outcome measures, except for cry duration, because of differences in study design. However, most of the individual studies that measured pain found sucrose to significantly reduce pain compared with the control group. One study compared sucrose and Lidocaine-prilocaine cream and no significant difference was found between the two treatments for the outcomes pain and cry duration. Due to the differences between the studies, we were unable to identify the optimal concentration, volume or method of administration of sweet-tasting solutions in infants aged one to 12 months. Further large RCTs are needed.

AUTHORS' CONCLUSIONS

There is insufficient evidence to confidently judge the effectiveness of sweet-tasting solutions in reducing needle-related pain in infants (one month to 12 months of age). The treatments do, however, appear promising. Data from a series of individual trials are promising, as are the results from a subset meta-analysis of studies measuring duration of crying. Further well controlled RCTs are warranted in this population to determine the optimal concentration, volume, method of administration, and possible adverse effects.

Procedural pain and oxidative stress in premature neonates

Preterm neonates exposed to painful procedures in the neonatal intensive care unit exhibit increased pain scores and alterations in oxygenation and heart rate. It is unclear whether these physiological responses increase the risk of oxidative stress. Using a prospective study design, we examined the relationship between a tissue-damaging procedure (TDP; tape removal during discontinuation of an indwelling central arterial or venous catheter) and oxidative stress in 80 preterm neonates. Oxidative stress was quantified by measuring uric acid (UA) and malondialdehyde (MDA) concentration in plasma before and after neonates (n = 38) experienced a TDP compared to those not experiencing any TDP (control group, n = 42). Pain was measured before and during the TDP using the Premature Infant Pain Profile (PIPP). We found that pain scores were higher in the TDP group compared to the control group (median scores, 11 and 5, respectively; P < .001). UA significantly decreased over time in control neonates but remained stable in TDP neonates (132.76 to 123.23 μM versus 140.50 to 138.9 μM; P = .002). MDA levels decreased over time in control neonates but increased in TDP neonates (2.07 to 1.81 μM versus 2.07 to 2.21 μM, P = .01). We found significant positive correlations between PIPP scores and MDA. Our data suggest a significant relationship between procedural pain and oxidative stress in preterm neonates.

PERSPECTIVE

This article presents data describing a significant relationship between physiological markers of neonatal pain and oxidative stress. The method described in this paper can potentially be used to assess the direct cellular effects of procedural pain as well the effectiveness of interventions performed to decrease pain.

The effect of a familiar scent on the behavioral and physiological pain responses in neonates

There are adverse physiologic effects of pain in neonates, and effective pain management must be an essential aspect of neonatal care. In this study we assessed the effect of a nonmaternal familiar scent on the neonatal pain responses. This study included 135 neonates randomly assigned to one of three groups. During arterial puncture, one group was exposed to a vanillin scent on a gauze pad held next to their nose. They were familiarized with it the night before blood sampling by a scented gauze pad placed in the incubator next to their head for an average duration of 8.65 hours. The second group was not familiarized with the scent but was exposed to it during the procedure. The third group was neither familiarized nor exposed to the scent. The duration of crying in the familiar scent group was significantly lower than in the two other groups. Comparison of the physiologic parameters showed less variation in oxygen saturation level during arterial puncture in the familiar scent group. In this study, a familiar scent could reduce crying and oxygen consumption during arterial puncture.

The effectiveness of glucose in reducing needle-related procedural pain in infants

This systematic review examined the effectiveness of glucose in relieving needle-associated pain in infants. Meta-analysis was not undertaken, and there was variation in dose, administration method, concentration, and outcome measurement. Glucose was more effective than placebo in relieving infant pain as measured by behavioral outcomes, but there were mixed findings for physiological outcomes. Based on these findings, 25%-50% glucose appears effective for infant pain management.

The use of oral sucrose for procedural pain relief in infants up to six months of age: a randomized controlled trial

The aim of this study was to evaluate the effectiveness of oral sucrose in decreasing pain during minor procedures in infants of 1-6 months corrected age. A blinded randomized controlled trial with infants aged 4-26 weeks who underwent venipuncture, heel lance or intravenous cannulation were stratified by corrected age into > 4-12 weeks and > 12-26 weeks. They received 2 mL of either 25% sucrose or sterile water orally 2 minutes before the painful procedure. Nonnutritional sucking and parental comfort, provided in adherence to hospital guidelines, were recorded. Pain behavior was recorded using a validated 10 point scale at baseline, during and following the procedure. Data collectors were blinded to the intervention. A total of 21 and 20 infants received sucrose and water, respectively, in the > 4-12-week age group, and 21 and 22, respectively, in the > 12-26-week age group. No statistical differences were found in pain scores between treatment and control groups at any data collection points in either age group. Infants aged > 4-12 weeks who did nonnutritional sucking showed statistically significantly lower median pain scores at 1, 2, and 3 minutes after the procedure than those who did not suck. Infants aged > 4-26 weeks exhibited pain behavior scores that indicated moderate to large pain during painful procedures; however, there was insufficient evidence to show that 2 mL 25% sucrose had a statistically significant effect in decreasing pain. Infants should be offered nonnutritional sucking in compliance with the Baby Friendly Health Initiative during painful procedures.

Sex Differences in Pain Responses at Maturity Following Neonatal Repeated Minor Pain Exposure in Rats

There is mounting evidence of long-lasting changes in pain sensitivity in school-age children who were cared for in a neonatal intensive care unit. Such care involves multiple pain exposures, 70% of which are accounted for by heel lance to monitor physiological well-being. The authors sought to model the repeated brief pain resulting from heel lance by administering repeated paw needle stick to neonatal rat pups. Repeated needle stick during the first 8 days of life was sex-specific in altering responses to mechanical and inflammatory stimuli, but not to a thermal stimulus, at maturity. Specifically, neonatal paw needle stick males exhibited significantly greater mechanical sensitivity in response to von Frey hair testing, whereas neonatal paw needle stick females exhibited significantly greater pain behavior scores following hindpaw formalin injection. This is the first study to show such sex-dependent changes in pain responsiveness at maturity in animals having experienced repeated neonatal needle stick pain. These findings support existing evidence that there are long-term sensory sequelae following neonatal pain experiences in rats and further suggest that there are sex-linked differences in the nature of the consequences. If these relationships hold in humans, these findings suggest that even mild painful insults early in life are not without sensory consequences.

Oral glucose solution as pain relief in newborns: results of a clinical trial

BACKGROUND

It was long believed that newborns could not experience pain. As it is now documented that newborns have all the necessary systems to perceive pain, pain management can no longer be ignored. The objective of this study is to investigate which concentration of glucose is most effective in reducing pain for venipuncture in the newborn.

METHODS

This double-blind clinical trial of 304 newborns was conducted on a maternity and neonatal ward (neonatal medium intensive care unit). During at least 1 month, one of the four selected solutions (10, 20, 30% glucose, and placebo) was administered orally, 2 minutes before the venipuncture was performed. The pain from the skin puncture was scored using a validated pain scale (the "Leuven Pain Scale").

RESULTS

This study showed a significantly lower average pain score in the 30 percent glucose group (3.99) when compared with the placebo group (8.43). The average pain scores in the 20 percent glucose group (5.26) and the 10 percent glucose group (5.92) were also significantly lower than those in the placebo group.

CONCLUSION

Oral administration of 2 mL of 30 percent glucose 2 minutes before the venipuncture provides the most effective pain reduction in newborns.

Using non-nutritive sucking and oral glucose solution with neonates to relieve pain: a randomised controlled trial

AIM

To compare the efficacies of non-nutritive sucking and glucose solution as pain-relief interventions for neonates undergoing a venipuncture procedure.

BACKGROUND

Neonates may be subjected to painful procedures. The individual efficacies of non-nutritive sucking or oral glucose solution used alone on pain-relief for neonates still remain controversial.

DESIGN

A randomised, parallel-group controlled trial was designed.

METHODS

A total of 105 neonates were randomly assigned to one of the three groups: non-nutritive sucking, glucose solution, or control group. When a neonate underwent a venipuncture during a newborn screening test, his/her pain manifestations were videotaped and subsequently measured using the Neonatal Infant Pain Scale. Both the stability analysis and the analysis of repeated relationships were performed by generalised estimating equations.

RESULTS

The level of pain was regressed over the study variables (time and group) and covariate (gestational age). Both the non-nutritive sucking and glucose solution groups had significantly lower pain scores than the control group during the venipuncture and recovery phases. Furthermore, non-nutritive sucking seemed to be more effective than glucose solution.

CONCLUSION

Nurses can use a pain assessment tool and the pain-relief intervention to improve the quality of neonatal care in clinical practice. This study indicates that either non-nutritive sucking or glucose solution can effectively decrease the level of pain.

RELEVANCE TO CLINICAL PRACTICE

If a painful procedure on neonates is inevitable, simple, convenient and effective pain-relief methods such as non-nutritive sucking or glucose solution can be provided alone. Based on a neonate's condition, nurses can provide 2 ml of 25% glucose solution through a syringe for a breastfeeding infant before an invasive procedure if nipple confusion is the concern.

Stress and pain relief in the care of the surgical neonate

In recent years, there has been a major change in our thinking about the way neonates experience stress. This understanding has led to advances in anesthetic technique and the pre- and postoperative care of the surgical neonate. Stress can develop before birth due to placental insufficiency. This can lead to preterm delivery, and the preterm infant is much more vulnerable to stressful stimulus. Stress is detrimental to the neonate in the short term and can also have adverse effects on the future wellbeing of the child. Limiting stress is not just about good pain control. The nursing environment is vitally important. Much can be achieved with good attention to detail in this respect. The effects of stress and the ways they can be minimized are discussed.

How well do clinical pain assessment tools reflect pain in infants?

BACKGROUND

Pain in infancy is poorly understood, and medical staff often have difficulty assessing whether an infant is in pain. Current pain assessment tools rely on behavioural and physiological measures, such as change in facial expression, which may not accurately reflect pain experience. Our ability to measure cortical pain responses in young infants gives us the first opportunity to evaluate pain assessment tools with respect to the sensory input and establish whether the resultant pain scores reflect cortical pain processing.

METHODS AND FINDINGS

Cortical haemodynamic activity was measured in infants, aged 25-43 wk postmenstrual, using near-infrared spectroscopy following a clinically required heel lance and compared to the magnitude of the premature infant pain profile (PIPP) score in the same infant to the same stimulus (n = 12, 33 test occasions). Overall, there was good correlation between the PIPP score and the level of cortical activity (regression coefficient = 0.72, 95% confidence interval [CI] limits 0.32-1.11, p = 0.001; correlation coefficient = 0.57). Of the different PIPP components, facial expression correlated best with cortical activity (regression coefficient = 1.26, 95% CI limits 0.84-1.67, p < 0.0001; correlation coefficient = 0.74) (n = 12, 33 test occasions). Cortical pain responses were still recorded in some infants who did not display a change in facial expression.

CONCLUSIONS

While painful stimulation generally evokes parallel cortical and behavioural responses in infants, pain may be processed at the cortical level without producing detectable behavioural changes. As a result, an infant with a low pain score based on behavioural assessment tools alone may not be pain free.

Stress at three-month immunization: parents' and infants' salivary cortisol response in relation to the use of pacifier and oral glucose

The aims of the present study were to investigate (1) whether the salivary cortisol response could be dampened during a routine three-month immunization if the infant received sweet-tasting solution in combination with a pacifier and (2) stress experienced by parents during immunization of the infant. Ninety-eight infants were included into one of four intervention groups: 'glucose and pacifier', 'water and pacifier', 'glucose', or 'water'. Saliva was collected before and 30 min after the immunization. Infants' crying-time and parents' self-reported stress (VAS) were measured before and after immunization. Infants in the 'pacifier and glucose' group had a significantly smaller change in salivary cortisol than infants in the other groups (F(3,72)=3.1, p<0.05). In the 'glucose and pacifier' group the median salivary cortisol levels decreased 33% after the immunization. In the 'water and pacifier', 'glucose', and 'water' group median cortisol increased with 50%, 42%, and 8%, respectively. No significant differences in crying-time were observed between the intervention groups. If the infant cried before the immunization, the crying-time during the immunization was longer (p<0.01) and cortisol increased more (p<0.05). Median cortisol levels for parents decreased after the immunization (p<0.01). Median VAS increased 50% (p<0.0001) after immunization. First time parents rated higher stress on VAS before immunization (p<0.01). Parents' change in cortisol and VAS were significantly related to infants' crying time. In conclusion, the combination of oral glucose and pacifier dampen infants' salivary cortisol in response to the three-month immunization.

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.

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.

State of the science: procedural pain management in the neonate

Neonates in the neonatal intensive care unit experience painful procedures. Over the last 10 years, investigators have examined several pharmacologic and nonpharmacolgic treatment strategies to decrease or eliminate the pain associated with mechanical ventilation, endotrachial intubation, insertion of percutaneous or central venous lines, heel stick, and venipuncture. These procedures and others are addressed as well as the reported severity of pain associated with these procedures. Progress has been made in the past decade to establish evidence-based treatments that will help the clinician more effectively relieve neonatal stress and pain when performing many routine procedures.

Effect of oral glucose on the heart rate of healthy newborns

AIM

Increases in heart rate have been widely utilized as pain responses in different studies. In a previous study, we found an increase in heart rate in newborns when they received glucose as pain relief. Other research groups have shown a smaller increase in heart rate on administration of sweet solutions. We therefore investigated the question as to whether or not oral glucose itself can cause an increased heart rate in healthy infants.

METHOD

This was a randomized, controlled, double-blind study comprising 70 healthy newborns. They were randomly allocated to receive 1 ml 30% glucose or 1 ml placebo solution (sterile water) orally without undergoing any painful procedure. The heart rate was recorded during and at different times after this administration.

RESULTS

The heart rate was significantly higher in the glucose than in the placebo group (p = 0.020). The highest heart rate was noted during treatment, and the heart rate subsequently decreased in both groups (p = 0.002).

CONCLUSION

Oral glucose causes an increase in heart rate in healthy newborns not undergoing any painful intervention.

Thermal thresholds predict painfulness of diabetic neuropathies

OBJECTIVE

Pathophysiology explaining pain in diabetic neuropathy (DN) is still unknown.

RESEARCH DESIGN AND METHODS

Thirty patients with peripheral DN (17 men and 13 women; mean age 52.4 +/- 2.5 years) were investigated. Fifteen patients had neuropathic pain, and 15 patients were free of pain. Patients were followed over 2 years and examined at the beginning and thereafter every 6 months. Clinical severity and painfulness of the DN were assessed by the neuropathy impairment score and visual analog scales (VASs). Cold and warm perception thresholds as well as heat pain thresholds were obtained for evaluation of Adelta- and C-fibers. Nerve conduction velocities (NCVs) and vibratory thresholds were recorded for analysis of thickly myelinated fibers. Moreover, for assessment of cardiac vagal function, heart rate variability (HRV) was evaluated. In order to reduce day-to-day variability of pain, mean values of the five time points over 2 years were calculated and used for further analysis. Data were compared with an age- and sex-matched control group of healthy volunteers.

RESULTS

There were significant differences regarding electrophysiological studies, HRV and quantitative sensory testing (QST) between patients and healthy control subjects (P < 0.001). Generally, patients with neuropathic pain were indistinguishable from pain-free patients. In the pain group, however, VAS pain ratings were correlated to the impairment of small-fiber function (cold detection thresholds, P = 0.02; warm detection thresholds, P = 0.056).

CONCLUSIONS

Intensity of pain in painful DN seems to depend on small nerve fiber damage and deafferentation.