Pain assessment in preterm neonates

An Evidence-Based Discussion of Fetal Pain and Stress

BACKGROUND

The concept of fetal pain results from procedures conducted without anesthesia in preterm newborns and fetuses, which indicate that it is possible to examine fetal pain based on stress hormone, metabolic, and behavioral changes. Anatomical and physiological data suggest that fetuses become capable of processing nociceptive stimuli around midgestation, although the associated changes in fetal brain development remain unclear. What constitutes fetal pain remains controversial in the light of the definition of pain adopted by the International Association for the Study of Pain (IASP), which posits pain as an "unpleasant sensory and emotional experience."

SUMMARY

Here, we examine the notion that human fetuses cannot "experience" pain and potential implications of this claim. We highlight the key scientific evidence related to fetal pain, including clinical studies on pain in fetuses and preterm newborns. We argue that consistent patterns of stress hormones, metabolic changes, body movements, hemodynamic changes, and pain-related facial expressions in fetuses exposed to invasive procedures overcome the need for subjective proof of pain as articulated in the IASP definition. No study to date has conclusively proven the absence of fetal pain beyond the age of viability.

KEY MESSAGES

Based on the current evidence, we propose that all fetuses receive anesthesia regardless of the invasive procedures being performed to guarantee the least possible pain and physiological, behavioral, or hormonal responses without exposing the mother or her baby to unnecessary complications.

Evaluation and Treatment of Pain in Fetuses, Neonates and Children

The perception of pain is individual and differs between children and adults. The structures required to feel pain are developed at 24 weeks of gestation. However, pain assessment is complicated, especially in neonates, infants and preschool-age children. Clinical scales adapted to age are the most used methods for assessing and monitoring the degree of pain in children. They evaluate several behavioral and/or physiological parameters related to pain. Some monitors detect the physiological changes that occur in association with painful stimuli, but they do not yet have a clear clinical use. Multimodal analgesia is recommended for pain treatment with non-pharmacological and pharmacological interventions. It is necessary to establish pharmacotherapeutic protocols for analgesia adjusted to the acute or chronic, type and intensity of pain, as well as age. The most used analgesics in children are paracetamol, ibuprofen, dipyrone, opioids (morphine and fentanyl) and local anesthetics. Patient-controlled analgesia is an adequate alternative for adolescent and older children in specific situations, such as after surgery. In patients with severe or persistent pain, it is very important to consult with specific pain services.

Premature Birth and Developmental Programming: Mechanisms of Resilience and Vulnerability

The third trimester of pregnancy represents a sensitive phase for infant brain plasticity when a series of fast-developing cellular events (synaptogenesis, neuronal migration, and myelination) regulates the development of neural circuits. Throughout this dynamic period of growth and development, the human brain is susceptible to stress. Preterm infants are born with an immature brain and are, while admitted to the neonatal intensive care unit, precociously exposed to stressful procedures. Postnatal stress may contribute to altered programming of the brain, including key systems such as the hypothalamic-pituitary-adrenal axis and the autonomic nervous system. These neurobiological systems are promising markers for the etiology of several affective and social psychopathologies. As preterm birth interferes with early development of stress-regulatory systems, early interventions might strengthen resilience factors and might help reduce the detrimental effects of chronic stress exposure. Here we will review the impact of stress following premature birth on the programming of neurobiological systems and discuss possible stress-related neural circuits and pathways involved in resilience and vulnerability. Finally, we discuss opportunities for early intervention and future studies.

Knowledge and Practices in Neonatal Pain Management of Nurses Employed in Hospitals with Different Levels of Referral-Multicenter Study

Background: One of the key elements of patient care is the relief and prevention of pain sensations. The importance of pain prevention and treatment has been emphasized by many international organizations. Despite the recommendations and guidelines based on evidence, contemporary research shows that the problem of pain among patients in neonatal intensive care units (NICUs) in various centers is still an important and neglected problem. Aim: The aim of this study was to assess the level of knowledge of the medical personnel and their perception of the issue of pain in neonatal patients. Methods: A quantitative descriptive study carried out in 2019. The study used a nurses’ perceptions of neonatal pain questionnaire. Results: A total of 43 Polish hospitals and 558 respondents participated in the project. 60.9% (n = 340) and 39.1% (n = 218) of respondents were employed in secondary and tertiary referral departments, respectively. Conclusion: Our analyses indicate that despite the availability of pain assessment tools for neonatal patients, only a few centers use standardized tools. The introduction of strategies to promote and extend the personnel’s awareness of neonatal pain monitoring scales is necessary.

Breastfeeding as an analgesic method during vaccinations

INTRODUCTION

Infants undergo painful stings such as intradermal and intramuscular stings during vaccination. Clinical trial have showed analgesic methods to reduce the painful in both infants and kids.

EVIDENCE ACQUISITION

There are different types of non-pharmacological interventions which have an analgesic effect in infants during vaccinations such as: breastfeeding, cladding the infants, the skin to skin contact, the use of sweetened substance.

EVIDENCE SYNTHESIS

A review of the primary and secondary literature was carried out in the database Medline(PubMed). The bibliographic research was focused on the critical reading of the studies of the last ten years. Eight articles, including seven randomized clinical trials and one systematic review have been found. All registered studies report a reduction of the average value of the pain measured through both validated rating scales and through the measurement of the average duration of the cry during and after the vaccination in breastfeed infants. However it hasn't been demonstrated a statistically significant improvement in physiological parameters.

CONCLUSIONS

It is desirable that the literature produce further studies related to the changes of the vital parameters during the breastfeeding which allow a clear comparison between clinical trials.

Effects of smelling amniotic fluid on preterm infant's pain and stress during peripheral cannulation: A randomized controlled trial

AIM

To investigate the effect of smelling amniotic fluid on preterm infants' pain and stress caused by peripheral cannulation.

METHODS

This was a randomized controlled trial. The study sample consisted of 80 preterm infants meeting the case selection criteria and infants were randomly assigned to each group. However, in addition to the infants excluded from the study, total number of the infants in all the groups was 61. Infants in the amniotic fluid group smelled amniotic fluid for 15 min before, during, and after the application of peripheral cannulation while those in the control group received routine care during the procedure. The Premature Infant Pain Profile was used to assess their pain levels, and salivary cortisol analysis was performed to evaluate stress levels.

RESULTS

Preterm infants in the amniotic fluid and control groups had similar baseline characteristics. However, the pain levels of infants in the amniotic fluid group were significantly lower than of those in the control group during and after the procedure. After the procedure, cortisol levels of the infants in the amniotic fluid group were lower than of those in the control group, although this difference was not significant.

CONCLUSION

The intervention of smelling amniotic fluid is a practice that can be used for reducing pain and stress of preterm infants during peripheral cannulation.

The Indonesian version of the Premature Infant Pain Profile-Revised: Translation and adaptation of a neonatal pain assessment

Purpose

Pain assessment is a key component of good pain management in hospitalized infants. This study aimed to translate and adapt a version of pain measurement in infants, the Premature Infant Pain Profile Revised (PIPP-R) into Indonesian.

Method

The adaptation process of the measuring instrument used a modified Brislin method which included forward translation, back translation 1, group discussion 1, back translation 2, group discussion 2, and pilot testing on neonatal nurses: feasibility test, inter-rater reliability using intraclass correlation (ICC), and internal consistency using Cronbach's α coefficient.

Results

The PIPP-R version in English has been translated into Indonesian. In general, nurses assessed this measuring instrument as feasible. The inter-rater reliability showed a high agreement (ICC = 0.968, P = 0.001) and this measuring instrument had good internal consistency (Cronbach's α = 0.856).

Conclusion

The Indonesian version of PIPP-R is easy to use and shows good psychometric properties. The use of this measuring instrument will help nurses and researchers obtain accurate infant pain intensity measurement values.

Managing Procedural Pain in the Neonate Using an Opioid-sparing Approach

PURPOSE

Pain in the neonate is often challenging to assess but important to control. Physicians often must balance the need for optimal pain control with the need to minimize oversedation and prolonged opioid use. Both inadequate pain control and overuse of opioids can have long-term consequences, including poor developmental outcomes. The aim of this review is to introduce a comprehensive approach to pain management for physicians, nurses, and surgeons caring for critically ill neonates, focusing on nonopioid alternatives to manage procedural pain.

FINDINGS

After review, categories of opioid-sparing interventions identified included (1) nonopioid pharmacologic agents, (2) local and regional anesthesia, and (3) nonpharmacologic alternatives. Nonopioid pharmacologic agents identified for neonatal use included acetaminophen, NSAIDs, dexmedetomidine, and gabapentin. Local and regional anesthesia included neuraxial blockade (spinals and epidurals), subcutaneous injections, and topical anesthesia. Nonpharmacologic agents uniquely available in the neonatal setting included skin-to-skin care, facilitated tucking, sucrose, breastfeeding, and nonnutritive sucking.

IMPLICATIONS

The use of various pharmacologic and interventional treatments for neonatal pain management allows for the incorporation of opioid-sparing techniques in neonates who are already at risk for poor neurodevelopmental outcomes. A multifactorial approach to pain control is paramount to optimize periprocedural comfort and to minimize the negative sequelae of uncontrolled pain in the neonate.

Pharyngoesophageal and cardiorespiratory interactions: potential implications for premature infants at risk of clinically significant cardiorespiratory events

The aims of this study were to 1) examine pharyngoesophageal and cardiorespiratory responses to provoking pharyngeal stimuli, and 2) to determine potential contributory factors impacting heart rate (HR) changes to provide insight into cardiorespiratory events occurring in preterm infants. Forty-eight neonates (19 females and 29 males, born at 27.7 ± 0.5 wk; mean ± SE) pending discharge on full oral feeds were studied at 38.7 ± 0.2 wk postmenstrual age using concurrent pharyngoesophageal manometry, electrocardiography, respiratory inductance plethysmography, and nasal airflow thermistor. Pharyngoesophageal and cardiorespiratory responses (prevalence, latency, and duration) were quantified upon abrupt pharyngeal water stimuli (0.1, 0.3, and 0.5 ml in triplicate). Mixed linear models and generalized estimating equations were used for comparisons between HR changes. Contributory factors included stimulus characteristics and subject characteristics. Of 338 pharyngeal stimuli administered, HR increased in 23 (7%), decreased in 108 (32%), and remained stable in 207 (61%) neonates. HR decrease resulted in repetitive swallowing, increased respiratory-rhythm disturbance, and decreased esophageal propagation rates (all, P < 0.05). HR responses were related to stimulus volume, stimulus flow rate, and extreme prematurity (all, P < 0.05). In preterm infants, HR remains stable in a majority of pharyngeal provocations. HR decrease, due to pharyngeal stimulation, is related to aberrant pharyngoesophageal motility and respiratory dysregulation and is magnified by prematurity. We infer that the observed aberrant responses across digestive, respiratory, and cardiovascular systems are related to maladaptive maturation of the parasympathetic nervous system. These aberrant responses may provide diagnostic clues for risk stratification of infants with troublesome cardiorespiratory events and swallowing difficulty. NEW & NOTEWORTHY Cardiorespiratory rhythms concurrent with pharyngeal, upper esophageal sphincter, and esophageal body responses were examined upon pharyngeal provocation in preterm-born infants who were studied at full-term maturation. Decreased heart rate (HR) was associated with extreme preterm birth and stimulus flow/volume. With HR decrease responses, aerodigestive reflex abnormalities were present, characterized by prolonged respiratory rhythm disturbance, repetitive multiple swallowing, and poor esophageal propagation. Promoting esophageal peristalsis may be a potential therapeutic target.

The influence of gestational age in the psychometric testing of the Bernese Pain Scale for Neonates

BACKGROUND

Assessing pain in neonates is challenging because full-term and preterm neonates of different gestational ages (GAs) have widely varied reactions to pain. We validated the Bernese Pain Scale for Neonates (BPSN) by testing its use among a large sample of neonates that represented all GAs.

METHODS

In this prospective multisite validation study, we assessed 154 neonates between 24 2/7 and 41 4/7 weeks GA, based on the results of 1-5 capillary heel sticks in their first 14 days of life. From each heel stick, we produced three video sequences: baseline; heel stick; and, recovery. Five blinded nurses rated neonates' pain responses according to the BPSN. The underlying factor structure of the BPSN, interrater reliability, concurrent validity with the Premature Infant Pain Profile-Revised (PIPP-R), construct validity, sensitivity and specificity, and the relationship between behavioural and physiological indicators were explored. We considered GA and gender as individual contextual factors.

RESULTS

The factor analyses resulted in a model where the following behaviours best fit the data: crying; facial expression; and, posture. Pain scores for these behavioural items increased on average more than 1 point during the heel stick phases compared to the baseline and recovery phases (p < 0.001). Among physiological items, heart rate was more sensitive to pain than oxygen saturation. Heart rate averaged 0.646 points higher during the heel stick than the recovery phases (p < 0.001). GA increased along with pain scores: for every additional week of gestation, the average increase of behavioural pain score was 0.063 points (SE = 0.01, t = 5.49); average heart rate increased 0.042 points (SE = 0.01, t = 6.15). Sensitivity and specificity analyses indicated that the cut-off should increase with GA. Modified BPSN showed good concurrent validity with the PIPP-R (r = 0.600-0.758, p < 0.001). Correlations between the modified behavioural subscale and the item heart rate were low (r = 0.102-0.379).

CONCLUSIONS

The modified BPSN that includes facial expression, crying, posture, and heart rate is a reliable and valid tool for assessing acute pain in full-term and preterm neonates, but our results suggest that adding different cut-off points for different GA-groups will improve the BPSN's clinical usefulness.

TRIAL REGISTRATION

The study was retrospectively registered in the database of Clinical Trial gov. Study ID-number: NCT 02749461 . Registration date: 12 April 2016.

Use of off-label and unlicensed medicines in neonatal intensive care

Purpose

To evaluate the use of off-label and unlicensed medicines in a neonatal intensive care unit (NICU) of a teaching maternity hospital specialized in high risk pregnancy.

Methods

A prospective cohort study was conducted between August 2015 and July 2016. All newborns admitted to the NICU who had at least one medication prescribed and a hospital stay longer than 24 hours were included. The classification of off-label and unlicensed drugs for the neonatal population was done according to the information of Food and Drug Administration.

Results

A total of 17421 medication items were analyzed in 3935 prescriptions of 220 newborns. The proportion of newborns exposed to off-label drugs was 96.4%, and to unlicensed medicines was 66.8%. About one-half (49.3%) of the medication items were off-label and 24.6% were unlicensed. The main reason for off-label and unlicensed classification was, respectively, frequency of administration and the administration of adaptations of pharmaceutical forms.

Conclusions

Although there are actions to encourage the development of pharmacological studies with neonates, this study observed a high rate of prescription and exposure of newborns to off-label and unlicensed drugs in NICUs and pointed out areas of neonatal therapy that require scientific investment.

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.

Assessment of continuous pain in newborns admitted to NICUs in 18 European countries

AIM

Continuous pain occurs routinely, even after invasive procedures, or inflammation and surgery, but clinical practices associated with assessments of continuous pain remain unknown.

METHODS

A prospective cohort study in 243 neonatal intensive care units (NICUs) from 18 European countries recorded the frequency of pain assessments, use of mechanical ventilation, sedation, analgesia or neuromuscular blockade for each neonate for up to 28 days after NICU admission.

RESULTS

Only 2113 of 6648 (31.8%) of neonates received assessments of continuous pain, occurring variably among tracheal ventilation (TrV, 46.0%), noninvasive ventilation (NiV, 35.0%) and no ventilation (NoV, 20.1%) groups (p < 0.001). Daily assessments for continuous pain occurred in only 10.4% of all neonates (TrV: 14.0%, NiV: 10.7%, NoV: 7.6%; p < 0.001). More frequent assessments of continuous pain occurred in NICUs with pain guidelines, nursing champions and surgical admissions (all p < 0.01), and for newborns <32 weeks gestational age, those requiring ventilation, or opioids, sedatives-hypnotics, general anaesthetics (O-SH-GA) (all p < 0.001), or surgery (p = 0.028). Use of O-SH-GA drugs increased the odds for pain assessment in the TrV (OR:1.60, p < 0.001) and NiV groups (OR:1.40, p < 0.001).

CONCLUSION

Assessments of continuous pain occurred in less than one-third of NICU admissions and daily in only 10% of neonates. NICU clinical practices should consider including routine assessments of continuous pain in newborns.

EDIN Scale Implemented by Gestational Age for Pain Assessment in Preterms: A Prospective Study

Background. Chronic neonatal pain can lead to long-term adverse effects on the immature brain. EDIN scale for prolonged pain might not be fully suitable for premature infants. We aimed to test a modified EDIN scale, adding postmenstrual age (PMA) as a sixth item (EDIN6). Methods. In a two-phase prospective study, pain was assessed in all neonates admitted in our NICU. In T1 EDIN was applied; in T2 EDIN6 with additional scores of 2, 1, and 0, respectively, for 25–32, 33–37, and >37 weeks PCA was tested. Scores > 6 suggested pain. The nursing staff was given a questionnaire to evaluate EDIN and EDIN6. Results. A total of 15960 pain assessments were recorded (8693 in T1; 7267 in T2). With EDIN6, cumulative detection of pain almost tripled (117/7267 versus 52/8693, p = 0.001). Main differences were found among less mature categories (50/1472 versus 17/1734, p = 0.001 in PCA 25–32; 26/2606 versus 10/4335, p = 0.001 in PMA 33–37; 41/3189 versus 25/2624, p = 0.26 in PMA > 37). Adequacy of pain assessment in lower PMA was judged “medium-high” in 13,4% of nurses in T1 and 71,4% in T2. Conclusions. EDIN6 may allow improved evaluation of pain in preterm infants.

[Pain assessment scales in newborns: integrative review]

OBJECTIVE

To analyze studies on methods used to assess pain in newborns.

DATA SOURCES

Integrative review study of articles published from 2001 to 2012, carried out in the following databases: Scopus, PubMed, CINAHL, LILACS and Cochrane. The sample consisted of 13 articles with level of evidence 5.

DATA SYNTHESIS

29 pain assessment scales in newborns, including 13 one-dimensional and 16 multidimensional, that assess acute and prolonged pain in preterm and full-term infants were available in scientific publications.

CONCLUSION

Based on the characteristics of scales, one cannot choose a single one as the most appropriate scale, as this choice will depend on gestational age, type of painful stimulus and the environment in which the infant is inserted. It is suggested the use of multidimensional or one-dimensional scales; however, they must be reliable and validated.

The Validity and Clinical Utility of the COVERS Scale and Pain Assessment Tool for Assessing Pain in Neonates Admitted to an Intensive Care Unit

OBJECTIVES

Infants admitted to a neonatal intensive care unit (NICU) are routinely subject to a range of painful procedures. However, pain assessments in NICUs are under-utilized due to a lack of a gold standard pain measure. In this study we assessed the psychometric properties and clinical utility of the COVERS and Pain Assessment Tool (PAT), in a neonatal unit.

METHODS

We had 72 nurses use the scales to assess pain at baseline and during a heel-lance procedure in 80 NICU infants. An independent research observer and the infant's mother also completed pain ratings. After the study, we assessed nurse preference and clinical utility ratings for both scales.

RESULTS

The COVERS had satisfactory internal consistency at baseline (Cronbach α=0.74) and heel lance (α=0.78), as did the PAT (baseline α=0.79, heel lance α=0.85). Intraclass correlation coefficients demonstrated good inter-rater reliability at baseline and heel lance, respectively, for both the COVERS (0.82 and 0.80) and the PAT (0.83 and 0.86). There were strong associations between total scores on the 2 scales at baseline (r=0.81, P<0.001) and heel lance (r=0.91, P<0.001), between researcher's ratings and total COVERS (ρ=0.75, P<0.001) and PAT scores (ρ=0.69, P<0.001), and between maternal ratings and total COVERS (r=0.74, P<0.05) and PAT scores (r=0.65, P<0.05). Both scales were sensitive to pain and nonpain events. Reliability and validity was mostly upheld across gestational age. Most nurses preferred the COVERS (52%) to the PAT (16%), and 32% had no preference.

DISCUSSION

This study builds on evidence for the COVERS scale and the PAT; both scales were reliable and valid measures of acute pain in neonates as premature as 24-week gestational age.

Missed Opportunities for Sedation and Pain Management at a Level III Neonatal Intensive Care Unit, India

BACKGROUND

Neonates in the neonatal intensive care unit (NICU) undergo a multitude of painful and stressful procedures during the first days of life. Stress from this pain can lead to neurodevelopmental problems that manifest in later childhood and should be prevented.

OBJECTIVE

To determine the number of painful procedures performed per day for each neonate, to verify documentation of painful procedures performed, and to, subsequently, note missed opportunities for providing pain relief to neonates.

METHODS

We conducted a cross-sectional study at a level III NICU located in a rural part of western India. A total of 69 neonates admitted for more than 24 h were included. Twenty-nine neonates were directly observed for a total of 24 h each, and another 40 neonatal records were retrospectively reviewed for the neonate's first 7 days of admission. All stressful and painful procedures performed on the neonate were recorded. Also recorded were any pharmaceutical pain relief agents or central nervous system depressants administered to the neonate before or at the time of the procedures. Average nurse-patient ratio was also calculated. Data were analyzed using descriptive statistics.

RESULTS

A documentation deficit of 2.2% was observed. The average nurse-patient ratio was 1.53:1. A total of 13711 procedures were recorded, yielding 44.1 (38.1 stressful, 3.8 mildly painful, and 2.2 moderately painful) procedures per patient day. Common stressful procedures were position changing (2501) and temperature recording (2208). Common mildly and moderately painful procedures were heel prick (757) and endotracheal suctioning (526), respectively. Use of pharmacological agents coincided with 33.48% of the procedures. The choice of drug and time of administration were inappropriate, indicating that the pharmacological agents were intended not for pain relief but rather for a coexisting pathology or as sedation from ventilation with no analgesia.

CONCLUSION

Stressful procedures are common in the NICU; mildly and moderately painful procedures fairly common. Almost two-thirds of the times, no pharmaceutical pain relief methods were used, and when administered, the pharmaceutical agents were seldom intended for pain relief; this implies poor pain management practices and emphasizes the imperative need for educating NICU nurses, residents, fellows, and attendings.

[Clinical assessment of pain in Spanish Neonatal Intensive Care Units]

INTRODUCTION

Clinical scales are currently the best method to assess pain in the neonate, given the impossibility of self-report in this age group. A study is designed with the aim of determining the current practices as regards the clinical assessment of pain in Spanish Neonatal Units and the factors associated with the use of clinical scales.

METHODS

A prospective longitudinal observational study was conducted. A total of 30 Units participated and 468 neonates were included.

RESULTS

Only 13 Units (43.3%) had pain assessment protocols. Pain was evaluated with a scale in 78 neonates (16.7%, 95% CI; 13.1-20.1) and the mean number of pain assessments per patient and per day was 2.3 (Standard Deviation; 4.8), with a median of 0.75. Of the total number of 7,189 patient-days studied, there was at least one pain assessment in 654 (9.1%). No pain assessment was performed with a clinical scale on any patient in 20 (66.7%) Units. Among those that did, a wide variation was observed in the percentage of patients in whom pain was assessed, as well as in the scales used. The CRIES (C-Crying; R-Requires increased oxygen administration; I-Increased vital signs; E-Expression; S-Sleeplessness) scale was that used in most Units. In the multivariate analysis, only invasive mechanical ventilation was associated with receiving a pain assessment with a scale (OR 1.46, P=.042).

DISCUSSION

The majority of neonates admitted into Intensive Care in Spain do not receive a pain assessment. Many units still do not routinely use clinical scales, and there is a wide variation between those that do use them. These results could serve as a basis for preparing national guidelines as regards pain in the neonate.

The Neonatal Pain, Agitation and Sedation Scale and the bedside nurse's assessment of neonates

OBJECTIVE

To determine the reliability of an objective measure of pain, agitation and sedation using the Neonatal Pain, Agitation and Sedation Scale (N-PASS) compared with nursing bedside assessment.

STUDY DESIGN

Neonates admitted in neonatal intensive care unit over a 6-month period were eligible. Pain and sedation were assessed with N-PASS, and a subjective questionnaire was administered to the bedside nurse.

RESULT

A total of 218 neonates were eligible (median: gestational age 34.6 weeks, age at assessment 7 days). N-PASS pain score correlated significantly with both nurses' pain score (Spearman coefficient (r)=0.37; P<0.001) and agitation score (r=0.56; P<0.001). N-PASS sedation score correlated with nurses' sedation score (r=-0.39; P<0.001). Adjusting for gestational age, day of life, intrauterine drug exposure and use of high frequency ventilation only slightly attenuated the correlations (r=0.36, 0.55 and -0.31, respectively).

CONCLUSION

The N-PASS captures nursing assessment of pain, agitation and sedation in this broad population and provides a quantitative assessment of subjective descriptions that often drives patient therapy.

Pain management in newborns

As a standard of care for preterm/term newborns effective pain management may improve their clinical and neurodevelopmental outcomes. Neonatal pain is assessed using context-specific, validated, and objective pain methods, despite the limitations of currently available tools. Therapeutic approaches reducing invasive procedures and using pharmacologic, behavioral, or environmental measures are used to manage neonatal pain. Nonpharmacologic approaches like kangaroo care, facilitated tucking, non-nutritive sucking, sucrose, and others can be used for procedural pain or adjunctive therapy. Local/topical anesthetics, opioids, NSAIDs/acetaminophen and other sedative/anesthetic agents can be incorporated into NICU protocols for managing moderate/severe pain or distress in all newborns.

Pain assessment scales in newborns: integrative review

OBJECTIVE: To analyze studies on methods used to assess pain in newborns.DATA SOURCES: Integrative review study of articles published from 2001 to 2012, carried out in the following databases: Scopus, PubMed, CINAHL, LILACS and Cochrane. The sample consisted of 13 articles with level of evidence 5.DATA SYNTHESIS: 29 pain assessment scales in newborns, including 13 one-dimensional and 16 multidimensional, that assess acute and prolonged pain in preterm and full-term infants were available in scientific publications.CONCLUSION: Based on the characteristics of scales, one cannot choose a single one as the most appropriate scale, as this choice will depend on gestational age, type of painful stimulus and the environment in which the infant is inserted. It is suggested the use of multidimensional or one-dimensional scales; however, they must be reliable and validated.

Development and psychometric properties of the Swedish ALPS-Neo pain and stress assessment scale for newborn infants

AIM

To validate and evaluate the psychometric properties of the ALPS-Neo, a new pain assessment scale created for the continuous evaluation of pain and stress in preterm and sick term infants.

METHODS

A unidimensional scale for continuous pain, Astrid Lindgren Children's Hospital Pain Scale (ALPS 1), was developed further to assess continuous pain and stress in infants treated in the neonatal intensive care unit (NICU). The pain scale includes observations of five behaviours. A manual was created, clarifying the scoring criteria. An internal and an external panel assessed face validity. Psychometric properties were evaluated in three different steps. Inter-rater reliability was estimated from video-based assessments (n = 625) using weighted kappa statistics (test I). Inter-rater reliability was further evaluated in test II (n = 125) and test III (n = 96) by real-time assessments using the intraclass correlation coefficient (ICC) and Cronbach's alpha.

RESULTS

The final inter-rater reliability (test III) was assessed as good with ICC 0.91 for the total score and 0.62-0.81 for the five items. Cronbach's alpha showed 0.95 for the total score.

CONCLUSION

ALPS-Neo is a new assessment tool for optimising the management of pain and stress in newborn infants in the NICU. It has proved easy to implement and user-friendly, permitting fast, reliable observations with high inter-rater reliability.

Invasive procedures in preterm children: brain and cognitive development at school age

BACKGROUND

Very preterm infants (born 24-32 weeks' gestation) undergo numerous invasive procedures during neonatal care. Repeated skin-breaking procedures in rodents cause neuronal cell death, and in human preterm neonates higher numbers of invasive procedures from birth to term-equivalent age are associated with abnormal brain development, even after controlling for other clinical risk factors. It is unknown whether higher numbers of invasive procedures are associated with long-term alterations in brain microstructure and cognitive outcome at school age in children born very preterm.

METHODS

Fifty children born very preterm underwent MRI and cognitive testing at median age 7.6 years (interquartile range, 7.5-7.7). T1- and T2-weighted images were assessed for the severity of brain injury. Magnetic resonance diffusion tensor sequences were used to measure fractional anisotropy (FA), an index of white matter (WM) maturation, from 7 anatomically defined WM regions. Child cognition was assessed using the Wechsler Intelligence Scale for Children-IV. Multivariate modeling was used to examine relationships between invasive procedures, brain microstructure, and cognition, adjusting for clinical confounders (eg, infection, ventilation, brain injury).

RESULTS

Greater numbers of invasive procedures were associated with lower FA values of the WM at age 7 years (P = .01). The interaction between the number of procedures and FA was associated with IQ (P = .02), such that greater numbers of invasive procedures and lower FA of the superior WM were related to lower IQ.

CONCLUSIONS

Invasive procedures during neonatal care contribute to long-term abnormalities in WM microstructure and lower IQ.

Intubation in the delivery room: experience with nasal midazolam

BACKGROUND

Neonates are often intubated in the delivery room (DR) without anesthesia because vascular access is impossible.

AIMS

To assess neonatal comfort and adverse events after use of nasal midazolam (nMDZ) for intubation in the DR.

STUDY DESIGN

Prospective data collection over 6months on the intubation of neonates with respiratory distress requiring tracheal instillation of surfactant.

SUBJECTS

Twenty-seven neonates with median (Q25-75) gestational age and birthweight of, respectively, 29 (27-33)weeks and 1270 (817-1942)g received a 0.1mg/kg dose of nMDZ, and intubation was performed at the onset of tonus resolution or apnea.

OUTCOME MEASURES

Comfort was assessed with a scale of hetero-pain assessment and electrical skin conductance monitoring. Continuous pulse oximetry was recorded in the first postnatal hour, with oscillometric blood pressure measurement every 10min.

RESULTS

Seventy percent of the patients required a single dose, with intubation performed 4.8 (3-9)min after administration. Combined electro-clinical assessment found adequate comfort during the procedure in 68% of neonates. Mean blood pressure decreased from 39 (34-44)mmHg before to 31 (25-33)mmHg 1h following nMDZ (p=0.011).

CONCLUSION

nMDZ provided rapid and effective sedation to intubate neonates in the DR but potentially exposed them to hypotension, thus requiring close hemodynamic monitoring.

Pain assessment and measurement in neonates: an updated review

Pain assessment and measurement are the cornerstones of pain management. Pain assessment connotes a comprehensive multidimensional description. Conversely, pain measurement provides a numeric quantitative description of each factor illustrating pain qualities. Pain scales provide a composite score used to guide practice and research. The type of infant pain instrument chosen is a significant factor in guiding pain management practice. The purpose of this review was to summarize current infant pain measures by introducing a conceptual framework for pain measurement. Although more than 40 infant pain instruments exist, many were devised solely for research purposes; several of the newly developed instruments largely overlap with existing instruments. Integration of pain management into daily practice remains problematic. Understanding how each instrument measures infant pain allows clinicians to make better decisions about what instrument to use with which infant and in what circumstances. In addition, novel new measurement techniques need further testing.

Update on pain assessment in sick neonates and infants

This article describes developments in pain assessment in critically ill neonates and infants during the last 5 to 6 years. Pain assessment instruments show a redundancy of items and a lack of profound psychometric background. Although most research focuses primarily on acute pain, in clinical practice there is also the challenge of assessing prolonged and/or persisting pain. The effectiveness of pain assessment is still a matter of debate and has recently been challenged as a primary end point in analgesia-related trials. Integration of observation of behavior with reliable and specific neurobiology-based parameters remains a challenge.

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.

Cerebral near-infrared spectroscopy as a measure of nociceptive evoked activity in critically ill infants

Signs of pain may be subtle or absent in a critically ill infant. The complex nature of pain may further obscure its identification and measurement. Because the use of monitoring and neuroimaging techniques has become more common in pain research, an understanding of these specialized technologies is important. Near-infrared spectroscopy (NIRS) is a noninvasive technique for monitoring tissue hemodynamics and oxygenation. There are indications that NIRS is capable of detecting the cerebral hemodynamic changes associated with sensory stimuli, including pain, in infants. These developments suggest that NIRS may play an important role in research focusing on pain perception in critically ill infants. The present review briefly describes the cortical responses to noxious stimuli, which parallel cerebral hemodynamic responses to various stimuli. This is followed by an overview of NIRS technology including a summary of the literature on functional studies that have used NIRS in infants. Current NIRS techniques have well-recognized limitations that must be considered carefully during the measurement and interpretation of the signals. Nonetheless, until more advanced NIRS techniques emerge, the current devices have strengths that should be exploited.

Nonnutritive sucking and oral sucrose relieve neonatal pain during intramuscular injection of hepatitis vaccine

CONTEXT

Newborns are subject to pain during routine invasive procedures. Pain caused by immunization injections is preventable, but remains untreated in neonates.

OBJECTIVES

The purpose of the study was to compare the effectiveness of three nonpharmacological pain relief strategies on newborns' pain, physiological parameters, and cry duration before, during, and after hepatitis B intramuscular (IM) injection.

METHODS

In this prospective, randomized clinical trial, we enrolled 165 newborns (gestational age, ≥36 weeks). The infants received IM injections and were randomized to three treatment groups: nonnutritive sucking (NNS), 20% oral sucrose, or routine care. Pain was measured by the Neonatal Facial Coding System, physiological signals by electrocardiogram monitors, and cry duration using a stopwatch.

RESULTS

Pain was significantly lower among infants in the NNS (B=-11.27, P<0.001) and sucrose (B=-11.75, P<0.001) groups than that in controls after adjusting for time effects, infant sleep/wake state, number of prior painful experiences, and baseline pain scores. Infants in the NNS and sucrose groups also had significantly lower mean heart and respiratory rates than the controls. Cry duration of infants receiving sucrose was significantly shorter than those in the NNS (Z=-3.36, P<0.001) and control groups (Z=-7.80, P<0.001).

CONCLUSION

NNS and oral sucrose can provide analgesic effects and need to be given before painful procedures as brief as a one-minute IM injection. Sucrose orally administered two minutes before injection more effectively reduced newborns' pain during injection than NNS. Both nonpharmacological methods more effectively relieved newborns' pain, stabilized physiological parameters, and shortened cry duration during IM hepatitis injection than routine care.

Pain management in newborns: from prevention to treatment

All neonates in the Neonatal Intensive Care Unit (NICU) or during the first days of life undergo painful and stressful procedures. Epidemiologic studies have shown that pain induced by these procedures is not effectively prevented or is inadequately treated. Pain experienced during the neonatal period may lead to negative outcomes, especially in preterm neonates. Prevention is the first step of pain management, and practical guidelines should be used in the NICU. Assessment must be done with adequate tools that take into account the infant's pathology and gestational age. Distinguishing between acute and prolonged pain is important for both assessment and treatment. The most common drugs that have been studied for the treatment of pain and stress are opioids, hypnosedatives, and NMDA receptor antagonists. Morphine and fentanyl are most frequently used for acute or prolonged pain in the NICU. They have potent analgesic effects and few immediate or long-term adverse effects. Midazolam is a commonly used hypnosedative, but its adverse effects limit its use. Drugs such as propofol and ketamine have been used for acute painful procedures; however, further research is needed to assess their long-term effects. Use of non-pharmacologic pain management techniques has increased in recent years. These methods are easy, inexpensive, and effective in helping newborns recover from painful procedures. Sweet solutions and non-nutritive sucking, breastfeeding, skin-to-skin mother care, swaddling, and facilitated tucking are the most commonly employed and evaluated non-pharmacologic methods. Hospitals should promote and improve parent involvement in pain management. In-service education and well organized hospital teams are crucial for successful implementation of pain protocols in newborns.

Use of analgesic and sedative drugs in the NICU: integrating clinical trials and laboratory data

Recent advances in neonatal intensive care include and are partly attributable to growing attention for comfort and pain control in the term and preterm infant requiring intensive care.Limitation of painful procedures is certainly possible, but most critically ill infants require unavoidable painful or stressful procedures such as intubation, mechanical ventilation, or catheterization.Many analgesics (opioids and nonsteroidal anti-inflammatory drugs)and sedatives (benzodiazepines and other anesthetic agents) are available but their use varies considerably among units. This review summarizes current experimental knowledge on the effects of sedative and analgesic drugs on brain development and reviews clinical evidence that speaks for or against the use of common analgesic and sedative drugs in the NICU but avoids any discussion of anesthesia during surgery. Risk/benefit ratios of intermittent boluses or continuous infusions for the commonly used sedative and analgesic agents are discussed in the light of clinical and experimental studies. The limitations of extrapolating experimental results from animals to humans must be considered while making practical recommendations based on the currently available evidence.

Must screening examinations for retinopathy of prematurity necessarily be painful?

PURPOSE

This study investigates the impact of the length of the examination, the insertion of eyelid specula, and the indentation of the globe on the pain and stress sensation of premature infants.

METHODS

Ninety-two premature infants in three neonatal wards were included. In two wards, the patients were examined using eyelid specula and scleral indentation as recommended in the official guidelines. In the third ward, the investigation time was minimized and ophthalmoscopy was performed without eyelid specula and scleral indentation. Physical and mental disturbance of the patients was assessed by the Neonatal Infant Pain Score and by monitoring the heart rate. The results were divided into two groups: in the one, eyelid specula and scleral indentation were used, whereas in the other one, they were not used. An independent-samples t-test was performed, which allowed us to calculate the correlation between the way the examination was executed and the condition of the patients.

RESULTS

Demographic data and baseline values of heart rate and pain score did not differ between the two groups. Heart rate and pain score during and after the investigation were significantly higher and increased significantly with the duration of the examination for the patients who were investigated using lid specula and scleral indentation.

CONCLUSION

Our study shows that indirect ophthalmoscopy without specula causes significantly less stress to infants than screening with lid specula and scleral indentation.

Electroencephalographic response to procedural pain in healthy term newborn infants

The current study aimed to characterize changes in EEG-related measures after noxious stimuli in neonates and to assess their potential utility as measures of pain and/or discomfort during neonatal intensive care. Seventy-two healthy term infants were investigated: Twenty-eight had a non-skin-breaking pin-prick on the heel, randomized to receive either oral glucose (n = 16) or water (n = 12) before the stimulus. Twenty-one infants were studied during a venous blood sample from the dorsum of the hand, 23 infants during a capillary heel stick. Behavioral pain responses were assessed with the Premature Infant Pain Profile Scale. The stimulus evoked a significant increase in higher frequency components (10-30 Hz) which also correlated to behavioral measures. The frontotemporal localization of the increased activity with frequency bands similar to electromuscular artifacts and the relation to behavioral measures confirmed that this activity corresponds to an increase in muscle tone. There was no change in frontal EEG asymmetry in any of the groups. The present results indicate that responses in cortical activity recorded by EEG are not useful for clinical assessment of infants' responses to noxious stimuli.

Current controversies regarding pain assessment in neonates

Although over 40 methods of pain assessment in infants are available for use in clinical practice, unrecognized and under-treated pain remains one of the most commonly reported problems within the Neonatal Intensive Care Units. A number of factors have been found to account for differences in the robustness of the pain response in neonates of varying gestational ages. Discrepancies between behavioral and physiological pain indicators have also been reported. With newer technologies, there is an opportunity not only to verify infant pain perception, but these tools may allow an identification of which of the observed indicators are most sensitive in particular clinical situations. The current controversies regarding pain assessment in preterm and term infants are reviewed to define the most important issues and to develop a dialogue for future directions.