Skin conductance versus the modified COMFORT sedation score as a measure of discomfort in artificially ventilated children

Non-pharmacological interventions for the prevention of pain during endotracheal suctioning in ventilated neonates

BACKGROUND

Pain, when treated inadequately, puts preterm infants at a greater risk of developing clinical and behavioural sequelae because of their immature pain system. Preterm infants in need of intensive care are repeatedly and persistently exposed to noxious stimuli, and this happens during a critical window of their brain development with peak rates of brain growth, exuberant synaptogenesis and the developmental regulation of specific receptor populations. Nearly two-thirds of infants born at less than 29 weeks' gestation require mechanical ventilation for some duration during the newborn period. These neonates are endotracheally intubated and require repeated endotracheal suctioning. Endotracheal suctioning is identified as one of the most frequent and most painful procedures in premature infants, causing moderate to severe pain. Even with improved nursing performance and standard procedures based on neonatal needs, endotracheal suctioning remains associated with mild pain.

OBJECTIVES

To evaluate the benefits and harms of non-pharmacological interventions for the prevention of pain during endotracheal suctioning in mechanically ventilated neonates. Non-pharmacological interventions were compared to no intervention, standard care or another non-pharmacological intervention.

SEARCH METHODS

We conducted searches in June 2023 in the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE via PubMed, Embase, CINAHL and three trial registries. We searched the reference lists of related systematic reviews, and of studies selected for inclusion.

SELECTION CRITERIA

We included randomised controlled trials (RCTs), quasi-RCTs and cluster-RCTs that included term and preterm neonates who were mechanically ventilated via endotracheal tube or via tracheostomy tube and required endotracheal suctioning performed by doctors, nurses, physiotherapists or other healthcare professionals.

DATA COLLECTION AND ANALYSIS

Our main outcome measures were validated composite pain scores (including a combination of behavioural, physiological and contextual indicators). Secondary outcomes included separate physiological and behavioural pain indicators. We used standard methodological procedures expected by Cochrane. For continuous outcome measures, we used a fixed-effect model and reported mean differences (MDs) with 95% confidence intervals (CIs). For categorical outcomes, we reported the typical risk ratio (RR) and risk difference (RD) and 95% CIs. We assessed risk of bias using the Cochrane RoB 1 tool, and assessed the certainty of the evidence using GRADE.

MAIN RESULTS

We included eight RCTs (nine reports), which enroled 386 infants, in our review. Five of the eight studies were included in a meta-analysis. All studies enrolled preterm neonates. Facilitated tucking versus standard care (four studies) Facilitated tucking probably reduces Premature Infant Pain Profile (PIPP) score during endotracheal suctioning (MD -2.76, 95% CI 3.57 to 1.96; I² = 82%; 4 studies, 148 infants; moderate-certainty evidence). Facilitated tucking probably has little or no effect during endotracheal suctioning on: heart rate (MD -3.06 beats per minute (bpm), 95% CI -9.33 to 3.21; I² = 0%; 2 studies, 80 infants; low-certainty evidence); oxygen saturation (MD 0.87, 95% CI -1.33 to 3.08; I² = 0%; 2 studies, 80 infants; low-certainty evidence); or stress and defensive behaviours (SDB) (MD -1.20, 95% CI -3.47 to 1.07; 1 study, 20 infants; low-certainty evidence). Facilitated tucking may result in a slight increase in self-regulatory behaviours (SRB) during endotracheal suctioning (MD 0.90, 95% CI 0.20 to 1.60; 1 study, 20 infants; low-certainty evidence). No studies reported intraventricular haemorrhage (IVH). Familiar odour versus standard care (one study) Familiar odour during endotracheal suctioning probably has little or no effect on: PIPP score (MD -0.30, 95% CI -2.15 to 1.55; 1 study, 40 infants; low-certainty evidence); heart rate (MD -6.30 bpm, 95% CI -16.04 to 3.44; 1 study, 40 infants; low-certainty evidence); or oxygen saturation during endotracheal suctioning (MD -0.80, 95% CI -4.82 to 3.22; 1 study, 40 infants; low-certainty evidence). No studies reported SRB, SDB or IVH. White noise (one study) White noise during endotracheal suctioning probably has little or no effect on PIPP (MD -0.65, 95% CI -2.51 to 1.21; 1 study, 40 infants; low-certainty evidence); heart rate (MD -1.85 bpm, 95% CI -11.46 to 7.76; 1 study, 40 infants; low-certainty evidence); or oxygen saturation (MD 2.25, 95% CI -2.03 to 6.53; 1 study, 40 infants; low-certainty evidence). No studies reported SRB, SDB or IVH.

AUTHORS' CONCLUSIONS

Facilitated tucking / four-handed care / gentle human touch probably reduces PIPP score. The evidence of a single study suggests that facilitated tucking / four-handed care / gentle human touch slightly increases self-regulatory and approach behaviours during endotracheal suctioning. Based on a single study, familiar odour and white noise have little or no effect on any of the outcomes compared to no intervention. The use of expressed breast milk or oral sucrose suggests that there is no discernible advantage of one method over the other for reducing pain during endotracheal suctioning. None of the studies reported on any of the prespecified secondary outcomes of adverse events.

Autonomic responses to pressure sensitivity of head, face and neck: Heart rate and skin conductance

Subjective scales are frequently used in the design process of head-related products to assess pressure discomfort. Nevertheless, some users lack fundamental cognitive and motor abilities (e.g., paralyzed patients). Therefore, it is vital to find non-verbal measurements of pressure discomfort and pressure pain. This study gathered the autonomic response data (heart rate and skin conductance) of 30 landmarks in head, neck and face from 31 participants experiencing pressure discomfort and pressure pain. The results indicate that pressure stimulation can change heart rate (HR) and skin conductance (SC). SC can be more useful in assessing pressure discomfort than HR for specific landmarks, and SC also possesses a faster arousal rate than HR. Moreover, HR decreased in response to pressure stimulation, while SC decreased followed by an increase. In comparisons between genders, the subjective pressure discomfort threshold (PDT) and pressure pain threshold (PPT) of women were lower than those of men, but men's autonomic responses (HR and SC) were more intense. Furthermore, there was no linear correlation between subjective pressure thresholds (PDT and PPT) and autonomic response intensity. This study has significant implications for resolving ergonomic issues (pressure discomfort and pain) associated with head-related products.

Evaluation of procedural pain for neonates in a neonatal intensive care unit: a single-centre study

BACKGROUND

To evaluate the procedural pain experienced by neonates in a neonatal intensive care unit (NICU) setting and determine the corresponding pain grades.

METHODS

Two experienced nurses independently used the Neonatal Infant Pain Scale (NIPS) to evaluate the neonatal pain during procedures taking place in the tertiary NICU and two level-two neonatal care units in the Children's Hospital of Zhejiang University School of Medicine. The mean and distribution of NIPS pain scores and the corresponding pain grades of participants when experiencing clinical painful procedures were analysed.

RESULTS

A total of 957 neonates exposed to 15 common clinical painful procedures were included in the study. The clinical painful procedures experienced by 957 participants could be divided into three groups: severe pain (NIPS score 5-7: peripheral intravenous cannulation, arterial catheterisation, arterial blood sampling, peripherally inserted central catheter placement and nasopharyngeal suctioning), mild to moderate pain (NIPS score 3-4: finger prick, intramuscular injection, adhesive removal, endotracheal intubation suctioning, heel prick, lumbar puncture and subcutaneous injection) and no pain to mild pain (NIPS score 0-2: gastric tube insertion, enema and intravenous injection).

CONCLUSIONS

The neonatal pain response to clinical procedures in NICU had certain pattern and preintervention drug analgesia could be taken for painful procedures with clustered high NIPS pain scores. Meanwhile, full coverage non-drug pain relief measures could be taken for procedures that are with scattered pain scores, and real-time pain evaluation should be provided to determine whether further drug analgesia is required.

Evaluation of Nociception during Pediatric Surgery: A Topical Review

The association between intraoperative nociception and increased patient's morbidity is well established. However, hemodynamic parameters, such as heart rate and blood pressure, may result in an inadequate monitor of nociception during surgery. Over the last two decades, different devices have been marketed to "reliably" detect intraoperative nociception. Since the direct measure of nociception is impractical during surgery, these monitors measures nociception surrogates such as sympathetic and parasympathetic nervous systems responses (heart rate variability, pupillometry, skin conductance), electroencephalographic changes, and muscular reflex arc. Each monitor carries its own advantages and disadvantages. The manuscript aims to give an overview of the most up-to-date information available in the literature on current nociceptor monitors available in clinical practice, with particular focus on their applications in pediatrics.

Autonomic measures identify stress, pain, and instability associated with retinopathy of prematurity ophthalmologic examinations

BACKGROUND

Retinopathy of prematurity (ROP) ophthalmologic examinations cause stress and pain. Infants' stress and pain can be measured non-invasively using skin conductance (SC) and high frequency heart rate variability (HF-HRV), reflecting sympathetic-mediated sweating and parasympathetic activity, respectively.

OBJECTIVES

To test the utility of SC to detect sympathetic activation during ROP examination, and the contribution of HF-HRV to predict stability post-examination.

METHODS

In this prospective, single center study, we measured SC continuously pre-, during, and post-examination, and HRV at 24 h pre-ROP examination. Clinical data included stability [apneas, bradycardias, and desaturations (A/B/Ds)], and interventions post-examination.

RESULTS

SC increased 56% above baseline during ROP examination (p = 0.001) and remained elevated post-examination (p = 0.02). Post-hoc analysis showed higher illness acuity, represented by need for respiratory support, was associated with lower HF-HRV at 24 h pre-ROP examination (p = 0.001). Linear regression indicated lower HF-HRV at 24 h pre-examination contributed to the need for higher intervention (i.e., stimulation to breathe, oxygen support) particularly among infants with higher illness acuity [F(1, 15) = 5.05, p = 0.04; β = -1.33, p = 0.04].

CONCLUSION

ROP examination induced a 2-fold increase in sympathetic activation which remained above baseline in recovery. Also, we propose that the low parasympathetic tone associated with autonomic imbalance contributes to instability and need for higher intervention to assure stabilization with A/B/D events. Our findings provide insight into the underestimation of adverse events associated with ROP examination and identification of infants who may be more vulnerable to potential sequelae following ROP examinations.

Opioid-Free Anaesthesia Effectiveness in Thoracic Surgery-Objective Measurement with a Skin Conductance Algesimeter: A Randomized Controlled Trial

BACKGROUND

Chest surgery is associated with significant pain, and potent opioid medications are the primary medications used for pain relief. Opioid-free anaesthesia (OFA) combined with regional anaesthesia is promoted as an alternative in patients with an opioid contraindication.

METHODS

Objective: To assess the efficacy of OFA combined with a paravertebral block in pain treatment during video-assisted thoracic surgery.

DESIGN

A randomized, open-label study.

SETTING

A single university hospital between December 2015 and March 2018.

PARTICIPANTS

Sixty-six patients scheduled for elective video-assisted thoracic surgery were randomized into two groups. Of these, 16 were subsequently excluded from the analysis.

INTERVENTIONS

OFA combined with a paravertebral block with 0.5% bupivacaine in the OFA group; typical general anaesthesia with opioids in the control group.

MAIN OUTCOME MEASURES

Intraoperative nociceptive intensity measured with a skin conductance algesimeter (SCA) and traditional intraoperative monitoring.

RESULTS

Higher mean blood pressure was observed in the control group before induction and during intubation (p = 0.0189 and p = 0.0095). During chest opening and pleural drainage, higher SCA indications were obtained in the control group (p = 0.0036 and p = 0.0253), while in the OFA group, the SCA values were higher during intubation (p = 0.0325). SCA during surgery showed more stable values in the OFA group. Pearson analysis revealed a positive correlation between the SCA indications and mean blood pressure in both groups.

CONCLUSIONS

OFA combined with a paravertebral block provides effective nociception control during video-assisted thoracic surgery and can be an alternative for general anaesthesia with opioids. OFA provides a stable nociception response during general anaesthesia, as measured by SCA.

Assessment of salivary cortisol concentrations for procedural pain monitoring in newborns

OBJECTIVES

The study aimed to evaluate the usefulness of salivary cortisol (SC) for the assessment of procedural pain intensity in preterm and term newborns.

METHODS

Three groups of neonates (term, 37⁰-41⁶ weeks; moderate to late preterm, 32⁰-36⁶; and very preterm, <32⁰) hospitalized in neonatal intensive care unit were assessed for the study. Response to nappy change, lung ultrasound (LUS), and blood sampling was analyzed. The intensity of pain was evaluated using continuous heart rate and blood oxygen saturation (SpO₂) monitoring, Neonatal Infant Pain Scale (NIPS), and SC concentrations. Saliva samples were collected before and 20 min after the procedure's end.

RESULTS

Seventy-one infants were examined: 30 term, 21 moderate to late preterm, and 20 very preterm. SC has increased significantly in response to nappy change only in very preterm newborns (2.13 ng/mL [1.55-3.68] vs. 2.84 ng/mL [1.93-9.06], p = 0.01). LUS did not affect concentrations of SC in any group. Significant increase in SC was observed after blood sampling in term and very preterm infants (2.2 ng/mL [1.45-2.92] vs. 4.29 ng/mL [3.88-5.73], p = 0.002, and 1.88 ng/mL [1.47-4.13] vs. 5.3 ng/mL [3.42-8.02], p = 0.002, respectively). A significant correlation between values of SC increase and NIPS scores was found (Spearman's rank correlation coefficient [r_s] = 0.31, p = 0.001).

CONCLUSIONS

We observed the increase in SC concentrations in response to painful stimulus. The presence of a correlation between NIPS scores and SC increase suggests that SC can be used as an objective parameter to assess pain in neonates.

Monitoring of analgesia level during general anesthesia in children

PURPOSE OF REVIEW

Monitoring of intraoperative nociception has made substantial progress in adult anesthesia during the last 10 years. Several monitors have been validated and their use has been associated with intraoperative or postoperative benefits in the adult population. In pediatric anesthesia, less data are available. However, several recent publications have assessed the performance of nociception monitors in children, and investigated their potential benefits in this context. This review will describe the main validated intraoperative nociception monitors, summarize adult findings and describe the available pediatric data.

RECENT FINDINGS

Six intraoperative nociception indices were included in this review. Among them, four have shown promising results in children: Surgical Pleth Index (GE-Healthcare, Helsinki, Finland), Analgesia-Nociception Index (Mdoloris Medical Systems, Loos, France), Newborn-Infant Parasympathetic Evaluation (Mdoloris Medical Systems), and Pupillometry (IDMED, Marseille, France). The relevance of Skin Conductance (MedStorm innovations, AS, Oslo, Norway) under general anesthesia could not be established. Finally, the Nociception Level (Medasense, Ramat Gan, Israel) still requires to be investigated in children.

SUMMARY

To date, four monitors may provide a relevant assessment of intraoperative nociception in children. However, the potential clinical benefits associated with their use to guide analgesia remain to be demonstrated.

Combining Electrodermal Activity With the Peak-Pain Time to Quantify Three Temporal Regions of Pain Experience

Background

Self-reported pain levels, while easily measured, are often not reliable for quantifying pain. More objective methods are needed that supplement self-report without adding undue burden or cost to a study. Methods that integrate multiple measures, such as combining self-report with physiology in a structured and specific-to-pain protocol may improve measures.

Method

We propose and study a novel measure that combines the timing of the peak pain measured by an electronic visual-analog-scale (eVAS) with continuously-measured changes in electrodermal activity (EDA), a physiological measure quantifying sympathetic nervous system activity that is easily recorded with a skin-surface sensor. The new pain measure isolates and specifically quantifies three temporal regions of dynamic pain experience: I. Anticipation preceding the onset of a pain stimulus, II. Response rising to the level of peak pain, and III. Recovery from the peak pain level. We evaluate the measure across two pain models (cold pressor, capsaicin), and four types of treatments (none, A=pregabalin, B=oxycodone, C=placebo). Each of 24 patients made four visits within 8 weeks, for 96 visits total: A training visit (TV), followed by three visits double-blind presenting A, B, or C (randomized order). Within each visit, a participant experienced the cold pressor, followed by an hour of rest during which one of the four treatments was provided, followed by a repeat of the cold pressor, followed by capsaicin.

Results

The novel method successfully discriminates the pain reduction effects of the four treatments across both pain models, confirming maximal pain for no-treatment, mild pain reduction for placebo, and the most pain reduction with analgesics. The new measure maintains significant discrimination across the test conditions both within a single-day's visit (for relative pain relief within a visit) and across repeated visits spanning weeks, reducing different-day-physiology affects, and providing better discriminability than using self-reported eVAS.

Conclusion

The new method combines the subjectively-identified time of peak pain with capturing continuous physiological data to quantify the sympathetic nervous system response during a dynamic pain experience. The method accurately discriminates, for both pain models, the reduction of pain with clinically effective analgesics.

Available Instruments to Assess Pain in Infants

Pain assessment in newborns and infants is challenging for clinicians. Although behavioral and behavioral-physiological scales are validated pain assessment instruments, their use in this age group has significant limitations. In this review, we summarize the methods currently available for assessing pain in neonates and infants. It is possible that these pain detection methods are also useful for assessing the quality of anesthesia and analgosedation in these populations. Further research should be aimed at confirming the usefulness of these tools in infants and identifying additional pain assessment options for clinical practice.

Prediction of Nociception in Children Using the Nociceptive Flexion Reflex Threshold and the Bispectral Index-A Prospective Exploratory Observational Study

OBJECTIVES

The prediction of patient responses to potentially painful stimuli remains a challenge in PICUs. We investigated the ability of the paintracker analgesia monitor (Dolosys GmbH, Berlin, Germany) measuring the nociceptive flexion reflex threshold, the cerebral sedation monitor bispectral index (Medtronic, Dublin, Ireland), the COMFORT Behavior, and the modified Face, Legs, Activity, Cry, Consolability Scale scores to predict patient responses following a noxious stimulus.

DESIGN

Single-center prospective exploratory observational study.

SETTING

Fourteen-bed multidisciplinary PICU at the University Children's Hospital, University Medical Center Hamburg Eppendorf, Germany.

PATIENTS

Children on mechanical ventilation receiving analgesic and sedative medications.

INTERVENTIONS

Noxious stimulation by way of endotracheal suctioning.

MEASUREMENTS AND MAIN RESULTS

Two independent observers assessed modified Face, Legs, Activity, Cry, Consolability and COMFORT Behavior Scales scores during noxious stimulation (n = 59) in 26 patients. Vital signs were recorded immediately before and during noxious stimulation; bispectral index and nociceptive flexion reflex threshold were recorded continuously. Mean prestimulation bispectral index (55.5; CI, 44.2-66.9 vs 39.9; CI, 33.1-46.8; p = 0.007), and COMFORT Behavior values (9.5; CI, 9.2-13.2 vs 7.5; CI, 6.7-8.5; p = 0.023) were significantly higher in observations with a response than in those without a response. Prediction probability (Pk) values for patient responses were high when the bispectral index was used (Pk = 0.85) but only fair when the nociceptive flexion reflex threshold (Pk = 0.69) or COMFORT Behavior Scale score (Pk = 0.73) was used. A logistic mixed-effects model confirmed the bispectral index as a significant potential predictor of patient response (p = 0.007).

CONCLUSIONS

In our sample of ventilated children in the PICU, bispectral index and nociceptive flexion reflex threshold provided good and fair prediction accuracy for patient responses to endotracheal suctioning.

The newborn infant parasympathetic evaluation index for acute procedural pain assessment in preterm infants

BACKGROUND

Accurate assessments of pain in hospitalized preterm infants present a major challenge in improving the short- and long-term consequences associated with painful experiences. We evaluated the ability of the newborn infant parasympathetic evaluation (NIPE) index to detect acute procedural pain in preterm infants.

METHODS

Different painful and stressful interventions were prospectively observed in preterm infants born at 25 + 0 to 35 + 6 weeks gestation. Pain responses were measured using the composite Premature Infant Pain Profile Revised (PIPP-R) scale, the NIPE index, and skin conductance responses (SCR). Outcome measures were correlations between the NIPE index, the PIPP-R score, and the SCR. Sensitivity/specificity analyses tested the accuracy of the NIPE index and SCR.

RESULTS

Two hundred and fifty-four procedures were recorded in 90 preterm infants. No significant correlation was found between PIPP-R and the NIPE index. PIPP-R and SCR were positively correlated (r = 0.27, P < 0.001), with stronger correlations for painful procedures (r = 0.68, P < 0.001) and especially for skin-breaking procedures (r = 0.82, P < 0.001). The NIPE index and SCR had high sensitivity and high negative predictive values to predict PIPP-R > 10, especially for skin-breaking painful procedures.

CONCLUSIONS

We found no significant correlation between the NIPE index and PIPP-R during routine painful or stressful procedures in preterm infants.

IMPACT

Exposure to repetitive pain can lead to neurodevelopmental sequelae. Behavior-based pain scales have limited clinical utility, especially for preterm infants. New devices for monitoring physiological responses to pain have not been validated sufficiently in preterm infants. This study found that the NIPE index was not significantly correlated to the validated PIPP-R scale during acute procedural pain. Secondary analysis of this study showed that NIPE index and SCRs may help to exclude severe pain in preterm infants. In clinical practice, measurements of physiological parameters should be combined with behavior-based scales for multidimensional pain assessments.

Using sensor-fusion and machine-learning algorithms to assess acute pain in non-verbal infants: a study protocol

INTRODUCTION

Objective pain assessment in non-verbal populations is clinically challenging due to their inability to express their pain via self-report. Repetitive exposures to acute or prolonged pain lead to clinical instability, with long-term behavioural and cognitive sequelae in newborn infants. Strong analgesics are also associated with medical complications, potential neurotoxicity and altered brain development. Pain scores performed by bedside nurses provide subjective, observer-dependent assessments rather than objective data for infant pain management; the required observations are labour intensive, difficult to perform by a nurse who is concurrently performing the procedure and increase the nursing workload. Multimodal pain assessment, using sensor-fusion and machine-learning algorithms, can provide a patient-centred, context-dependent, observer-independent and objective pain measure.

METHODS AND ANALYSIS

In newborns undergoing painful procedures, we use facial electromyography to record facial muscle activity-related infant pain, ECG to examine heart rate (HR) changes and HR variability, electrodermal activity (skin conductance) to measure catecholamine-induced palmar sweating, changes in oxygen saturations and skin perfusion, and electroencephalography using active electrodes to assess brain activity in real time. This multimodal approach has the potential to improve the accuracy of pain assessment in non-verbal infants and may even allow continuous pain monitoring at the bedside. The feasibility of this approach will be evaluated in an observational prospective study of clinically required painful procedures in 60 preterm and term newborns, and infants aged 6 months or less.

ETHICS AND DISSEMINATION

The Institutional Review Board of the Stanford University approved the protocol. Study findings will be published in peer-reviewed journals, presented at scientific meetings, taught via webinars, podcasts and video tutorials, and listed on academic/scientific websites. Future studies will validate and refine this approach using the minimum number of sensors required to assess neonatal/infant pain.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT03330496).

Pharmacotherapy of neonatal opioid withdrawal syndrome: a review of pharmacokinetics and pharmacodynamics

INTRODUCTION

Neonatal opioid withdrawal syndrome (NOWS) often arises in infants born to mothers who used opioids during pregnancy. Morphine, methadone, and buprenorphine are the most common first-line treatments, whereas clonidine and phenobarbital are generally reserved for adjunctive therapy. These drugs exhibit substantial pharmacokinetic (PK) and pharmacodynamic (PD) variability. Current pharmacological treatments for NOWS are based on institutional protocols and largely rely on empirical treatment of patient symptoms.

AREAS COVERED

This article reviews the PK/PD of NOWS pharmacotherapies with a focus on the implication of physiological development and maturation. Body size-standardized clearance is consistently low in neonates, except for methadone. This can be ascribed to underdeveloped metabolic and elimination pathways. The effects of pharmacogenetics have been clarified especially for morphine. The PK/PD relationship of medications used in the treatment of NOWS is generally understudied.

EXPERT OPINION

Providing an appropriate opioid dose in neonates is challenging. Advancements in quantitative pharmacology and PK/PD modeling approaches facilitate identification of key factors driving PK/PD variability and characterization of exposure-response relationships. PK/PD model-informed simulations have been widely employed to define age-appropriate pediatric dosing regimens. The model-informed approach holds promise to aid more rational use of medications in the treatment of NOWS.

Positioning Effects for Procedural Pain Relief in NICU: Systematic Review

OBJECTIVES

To systematically review the literature regarding the effectiveness of different positioning methods for procedural pain relief in neonates admitted to the Neonatal Intensive Care Unit (NICU).

DESIGN

A systemized search of the literature was carried out by means of two independent evaluators through the systematic search of electronic index databases.

DATA SOURCES

A search for relevant studies was performed in four databases (Medline, Web of Science, Scopus, and BVS-BIREME).

REVIEW/ANALYSIS METHODS

Manual searches were conducted on suitable references from the included articles, and 1,941 publications were eligible for the analysis. The flowchart for the articles' selection was based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria, and in relation to bias risks according to the Physiotherapy Evidence Database (PEDro) scale.

RESULTS

Based on the inclusion criteria, only 20 publications remained. According to the PEDro scale, 75% of the studies presented good methodological quality, with scores between 6 and 8, and 5% scored ≤4 points. None of them were blinded in relation to the therapies, but all of them performed intergroup statistical comparisons. According to the results of this review, we recommend facilitated tucking by parents (FTP) in NICU of at least 30 minutes duration, starting 15 minutes before, during the painful procedure, and 15 minutes after to relieve pain and to stabilize the physiological, hormonal, and behavioral responses of the newborns.

CONCLUSIONS

Positioning should be used as a nonpharmacological strategy for procedural pain relief in newborns. This review showed that facilitated tucking by parents for 30 minutes was the best position for pain relief in premature newborns during procedures in the NICU. Positioning is recommended as a nonpharmacological method for pain relief; FTP of at least 30 minutes duration should be the first positioning choice during procedures in the NICU.

[The effect of emotional stressors on postoperative skin conductance indices: a prospective cohort pilot study]

BACKGROUND

Skin conductance response reflects the activity of the sympathetic nervous system and is used to measure acute pain. This pilot study examines correlations of skin conductance response with emotional stressors postoperatively.

METHODS

The correlation of skin conductance response with pain, anxiety, nausea and intellectual task performance was analyzed in postoperative patients.

RESULTS

Significant correlations were observed between anxiety and pain during physical activity on both postoperative day 1 and 2. No significant correlations were found between skin conductance response versus mild pain, nausea, anxiety or intellectual task performance.

CONCLUSION

This pilot study suggests that when the pain is well-controlled in the early postoperative period, skin conductance response monitoring may not be influenced by other emotional stressors.

The effect of emotional stressors on postoperative skin conductance indices: a prospective cohort pilot study

Background

Skin conductance response reflects the activity of the sympathetic nervous system and is used to measure acute pain. This pilot study examines correlations of skin conductance response with emotional stressors postoperatively.

Methods

The correlation of skin conductance response with pain, anxiety, nausea and intellectual task performance was analyzed in postoperative patients.

Results

Significant correlations were observed between anxiety and pain during physical activity on both postoperative day 1 and 2. No significant correlations were found between skin conductance response versus mild pain, nausea, anxiety or intellectual task performance.

Conclusion

This pilot study suggests that when the pain is well-controlled in the early postoperative period, skin conductance response monitoring may not be influenced by other emotional stressors.

Pain assessment during eye examination for retinopathy of prematurity screening: Skin conductance versus PIPP-R

AIM

To assess changes in skin conductance during retinopathy of prematurity screening and to study the correlation between the skin conductance and a validated pain scale.

METHODS

Prospective observational study. Fifty-three eye examinations were performed in 32 preterm infant candidates for retinopathy of prematurity screening. Outcome measures were changes in Premature Infant Pain Profile-Revised (PIPP-R) scale and number of skin conductance fluctuations.

RESULTS

There was a significant increase from baseline in the number of skin conductance fluctuations and PIPP-R during the procedure. The maximum value of number of skin conductance fluctuations was 0.64 ± 0.44 peaks/sec, and the maximum value of PIPP-R was 10.8 ± 3.3. A correlation between the skin conductance and PIPP-R was not found at any time during the eye examination. Repeated measures correlation analyses showed only a moderate positive correlation between PIPP-R and number of skin conductance fluctuation values.

CONCLUSION

There were significant changes in both PIPP-R and number of skin conductance fluctuations during retinopathy of prematurity screening, reaffirming that this procedure is painful and stressful. The number of skin conductance fluctuations and PIPP-R are not significantly correlated, which likely reflects that these parameters evaluate different but complementary aspects of neonatal pain responses.

Assessment of Pain in the Newborn: An Update

Preterm and term neonate pain assessment in neonatal intensive care units is vitally important because of the prevalence of procedural and postoperative pain. Of the 40 plus tools available, a few should be chosen for different populations and contexts (2 have been validated in premature infants). Preterm neonates do not display pain behaviors and physiologic indicators as reliably and specifically as full-term infants, and are vulnerable to long-term sequelae of painful experiences. Brain-oriented approaches may become available in the future; meanwhile, neonatal pain assessment tools must be taught, implemented, and their use optimized for consistent, reproducible, safe, and effective treatment.

Nociception monitoring tools using autonomic tone changes for intraoperative analgesic guidance in pediatric patients

Nociception monitoring devices using changes in autonomic nervous system activity have been developed in numerous ways. Although there have been few studies conducted on children, compared to the relatively higher number of studies on adults, most of the nociception monitors in children, as in adults, appear to be more useful than the standard clinical practice that uses hemodynamic parameters in the evaluation and treatment of intraoperative nociception (pain) during general anesthesia. Particularly, when monitoring the surgical pleth index (SPI) in anesthetized children, the application of a new target range of SPI values (≤ 40) to the SPI monitoring criteria seems to be necessary for providing a more proper intraoperative analgesia. The analgesia nociception index (ANI) shows promising results in anesthetized adults, and recently, positive results along with cardiorespiratory coherence have been reported in pediatric patients. Newborn infant parasympathetic evaluation (NIPE) could be useful for providing adequate analgesia in newborns, infants, and children under 2 years of age in anesthetized or awake states. In cases of skin conductance and pupillometry, further studies are needed. Understanding the pros, cons, and limitations of these nociception monitoring tools will provide more effective and safe intraoperative analgesia to pediatric patients undergoing general anesthesia, and it may also help to plan and conduct promising research on the use of perioperative nociception monitoring in pediatric patients in the future.

Measurement of skin conductance responses to evaluate procedural pain in the perioperative setting

Background and aims The subjective nature of pain makes objective, quantitative measurements challenging. The current gold standard for evaluating pain is patient self-reporting using the numeric rating scale (NRS) or Visual Analog Scale. Skin conductance responses per second (SCR) measured in the palmar region reflect the emotional part of the autonomous nervous system. SCR ≥0.20 have been shown to indicate moderate or severe pain in the postoperative setting. We examined whether SCR can detect procedure-related pain before major surgery. Methods In 20 patients being prepared for major surgery SCR was recorded before and during arterial cannulation, after induction of anaesthesia, and on the first postoperative day. Self-reported pain was evaluated using NRS. NRS >3 was considered to represent moderate or severe pain. Results NRS was 0 [0-0] before arterial cannulation, increasing to 5 [3-6] during arterial cannulation (p<0.05). Before arterial cannulation SCR was 0.27 [0.20-0.27], increasing to 0.33 [0.30-0.37] during arterial cannulation (p<0.01). On the first postoperative day both SCR and reported pain indicated no more than mild pain, SCR 0.13 [0.00-0.20] and NRS 2.0 [0.5-2.0]. The sensitivity of SCR to indicate moderate or severe pain (NRS >3) was 0.93 (0.68-1.0) and specificity was 0.33 (0.25-0.35) when the cut-off established in the postoperative setting (SCR ≥0.20) was used on all data. Conclusions SCR increased during arterial cannulation. Before major surgery the SCR was above the threshold demonstrated to indicate pain in the postoperative setting, even without painful stimuli and no reported pain. Using the threshold established for postoperative pain, SCR cannot reliably discriminate between pain and other stressors before major surgery. Implications Before major surgery, the diagnosis of moderate or severe pain should not be made based on SCR ≥0.20.

Prematurity alters skin conductance and behavioural scoring after acute stress in term-equivalent age infants

AIM

The primary objective was to assess the effect of prematurity at term-equivalent age on skin conductance and behavioural responses to acute stress. The secondary objective was to explore the reliability of skin conductance in detecting neonatal discomfort in preterm and full-term populations.

METHODS

Very preterm infants at term-equivalent age and healthy full-term neonates, 34 infants in each group, underwent the hip dysplasia screening test. The acute pain in newborn infants (APN) scale was scored before and 15, 45 and 90 seconds after stimulus. Skin conductance was measured in the 30-second time-lap before and after stimulus.

RESULTS

The APN score was lower in preterm infants after intervention (term: 5.4 ± 2.8 vs. preterm: 3.9 ± 2.2; p = 0.03). Peaks-per-second, a skin conductance parameter, exhibited lower basal values in preterm infants than in term infants, with similar rise induced by stressful challenge. Peaks-per-second values were correlated to the 15-second APN score in both groups (term: r = 0.55, p < 0.001; preterm: r = 0.43, p = 0.01).

CONCLUSION

Preterm birth changed skin conductance signal and behavioural response to stress at term-equivalent age. The skin conductance device may be an objective tool for a continuous monitoring of acute neonatal stress.

Acute pain intensity monitoring with the classification of multiple physiological parameters

Current acute pain intensity assessment tools are mainly based on self-reporting by patients, which is impractical for non-communicative, sedated or critically ill patients. In previous studies, various physiological signals have been observed qualitatively as a potential pain intensity index. On the basis of that, this study aims at developing a continuous pain monitoring method with the classification of multiple physiological parameters. Heart rate (HR), breath rate (BR), galvanic skin response (GSR) and facial surface electromyogram were collected from 30 healthy volunteers under thermal and electrical pain stimuli. The collected samples were labelled as no pain, mild pain or moderate/severe pain based on a self-reported visual analogue scale. The patterns of these three classes were first observed from the distribution of the 13 processed physiological parameters. Then, artificial neural network classifiers were trained, validated and tested with the physiological parameters. The average classification accuracy was 70.6%. The same method was applied to the medians of each class in each test and accuracy was improved to 83.3%. With facial electromyogram, the adaptivity of this method to a new subject was improved as the recognition accuracy of moderate/severe pain in leave-one-subject-out cross-validation was promoted from 74.9 ± 21.0 to 76.3 ± 18.1%. Among healthy volunteers, GSR, HR and BR were better correlated to pain intensity variations than facial muscle activities. The classification of multiple accessible physiological parameters can potentially provide a way to differentiate among no, mild and moderate/severe acute experimental pain.

Electrodermal Activity Monitoring During Painful Stimulation in Sedated Adult Intensive Care Unit Patients: a Pilot Study

Introduction-Aim: Newer methods, such as infrared digital pupillometry and electrodermal activity (EDA) measurement have been suggested as good alternatives for analgesia monitoring in critically ill patients. This study analyzed EDA changes due to pain stimulus in sedated adult critical care patients Methods: Skin conductance variability, selected hemodynamic and respiratory parameters, Bispectral index (BIS) and ambient noise level, were monitored during 4 hour routine daytime in an adult ICU. 4h-Measurements were divided into 2 groups, based upon the sedation level of the patients: Group A - Ramsay Sedation Score 2-4 and Group B - Ramsay Sedation Score of 5-6. Selected recordings before and after pain stimulus were performed. The stimulus chosen was the pressure applied to nail bed for 10 sec, which was performed routinely during neurological examination. Patients' demographics, laboratory exams and severity scores were recorded. Pain status evaluation before every event was also performed by 2 independent observers via Critical Care Pain Observation Tool (CPOT) and Adult Non Verbal Pain Score (ANVPS) Results: In both groups the rate of EDA changes was greater than other monitoring parameters: more in Group A than in Group B. Yet, the difference between groups was not statistically significant.

CONCLUSION

EDA measurements are greater to pain stimuli, than cardiovascular, respiratory or even BIS monitoring. These encouraging results suggest that, further studies are needed to better define EDA role in ICU.

Administering atropine and ketamine before less invasive surfactant administration resulted in low pain scores in a prospective study of premature neonates

AIM

Less invasive surfactant administration (LISA) can avoid tracheal intubation for neonatal respiratory distress syndrome, but can be painful because it requires laryngoscopy. The aim of this study was to assess the efficacy and tolerance of intravenous atropine plus ketamine administration before LISA.

METHODS

We conducted a prospective observational study of all premature infants hospitalised in our French neonatal intensive care unit treated with LISA between March 2015 and March 2016. Ketamine was titrated by 0.5 mg/kg increments. The technical conditions, pain scores, emergent intubations and vital signs were collected and analysed.

RESULTS

Values are reported as medians (interquartile ranges). We included 29 patients with a gestational age of 29.6 (28.6-30.9) weeks and birth weight of 1290 (945-1600) grams. Technical conditions were satisfying for 24 infants (83%). The Faceless Acute Neonatal Pain Scale score was 2 (2-4); seven infants (24%) required tracheal intubation before LISA could be performed; 17 (59%) had a pulse oxymetry value under 80% that lasted more than 60 seconds. Heart rate and mean arterial blood pressure transiently increased.

CONCLUSION

Atropine plus ketamine before LISA resulted in low pain scores and stable haemodynamic parameters, but prolonged desaturations or apnoea leading to tracheal intubation were frequently observed.

A literature review of comfort in the paediatric critical care patient

AIMS AND OBJECTIVES

To investigate the meaning of comfort and to contextualise it within the framework of paediatric critical care.

BACKGROUND

The concept of comfort is closely linked to care in all health contexts. However, in specific settings such as the paediatric critical care unit, it takes on particular importance.

DESIGN

A literature review was conducted.

METHODS

A literature search was performed of articles in English and Spanish in international health science databases, from 1992-March 2017, applying the quality standards established by the PRISMA methodology and the Joanna Briggs Institute.

RESULTS

A total of 1,203 publications were identified in the databases. Finally, 59 articles which met the inclusion criteria were entered in this literature review. Almost all were descriptive studies written in English and published in Europe. The concept of comfort was defined as the immediate condition of being strengthened through having the three types of needs (relief, ease and transcendence) addressed in the four contexts of experience (physical, psychospiritual, social and environmental). Only two valid and reliable tools for assessing comfort were found: the Comfort Scale and the Comfort Behavior Scale.

CONCLUSIONS

Comfort is subjective and difficult to assess. It has four facets: physical, emotional, social and environmental. High levels of noise and light are the inputs that cause the most discomfort. Comfort is a holistic, universal concept and an important component of quality nursing care.

Electrodermal Activity during Blood Pooling for Arterial Blood Gases Analysis in Sedated Adult Intensive Care Unit Patients

Electrodermal activity (EDA) is considered a measure of autonomous nervous system activity. This study performed an exploratory analysis of the EDA changes during blood pooling for arterial blood gas analysis in sedated adult critical care patients and correlated the variations to other monitored parameters. EDA, along with other parameters, were monitored during 4 h routine daytime intensive care nursing and treatment in an adult ICU. 4 h measurements were divided into two groups based upon the sedation level. Selected recordings before and after blood pooling for arterial blood gases analysis (stress event) was performed. Nine stress events from Group A and 17 from Group B were included for further analysis. Patients’ demographics, laboratory exams, and severity scores were recorded. For both sedation levels, EDA changes are much greater than any other monitoring parameters used. The changes are noticed in both measurement (15 s and 60 s), even though in the 60 s measurement only selected EDA parameters are significantly changed after the start of the procedure. EDA measurements are more sensitive to a given stress event than cardiovascular or respiratory parameters. However, the present results could only be considered as a pilot study. More studies are needed in order to identify the real stress-load and clinical significance of such stimuli, which are considered otherwise painless in those patients.

Instruments to assess patient comfort during hospitalization: A psychometric review

AIM

To analyse the psychometric properties and the utility of instruments used to measure patient comfort, physical, social, psychospiritual and/or environmental, during hospitalization.

BACKGROUND

There are no systematic reviews nor psychometric reviews of instruments used to measure comfort, which is considered an indicator of quality in health care associated with quicker discharges, increased patient satisfaction and better cost-benefit ratios for the institution.

DESIGN

Psychometric review.

DATA SOURCES

MEDLINE, CINAHL, PsycINFO, Web of Knowledge, ProQuest Thesis&Dissertations, Google.

REVIEW METHODS

We limited our search to studies published between 1990-2015. The psychometric analysis was performed using the COnsensus-based Standards for the selection of health status Measurement INstruments (COSMIN), along with the Quality Criteria for Measurement Properties. The utility of the instruments was assessed according to their cost-efficiency, acceptability and educational impact. Protocol registration in PROSPERO, CRD42016036290.

RESULTS

Instruments reviewed showed moderate methodological quality and their utility was poorly reported. Thus, we cannot recommend any questionnaire without reservations, but the Comfort Scale, the General Comfort Questionnaire and their adaptations in adults and older patients, the Psychosocial Comfort Scale and the Incomfort des Patients de Reanimation are the most recommendable instruments to measure comfort.

CONCLUSIONS

The methodology of the studies should be more rigorous and authors should adequately report the utility of instruments. This review provides a strategy to select the most suitable instrument to assess patient comfort according to their psychometric properties and utility, which is crucial for nurses, clinicians, researchers and institutions.

Psychometric analysis of subjective sedation scales used for critically ill paediatric patients

AIMS

This study evaluated the psychometric properties of subjective sedation scales using one psychometric scoring system to identify the appropriate scale that is most suitable for clinical care practice.

BACKGROUND

A number of published sedation assessment scales for paediatric patients are currently used to attempt to achieve a moderate depth of sedation to avoid the undesirable effects caused by over- or undersedation. However, there has been no systematic review of these scales.

SEARCH STRATEGY

We searched the Cochrane Library, PubMed, EMBASE, the Cumulative Index to Nursing and Allied Health Literature, etc., to obtain relevant articles. The quality of the selected studies was evaluated according to the Consensus-based Standards for the Selection of Health Measurement Instruments checklist.

INCLUSION CRITERIA

Articles that had been published or were in press and discussed the psychometric properties of sedation scales were included. The population comprised critically ill infants and non-verbal children ranging in age from 0 to 18 years who underwent sedation in an intensive care unit.

FINDINGS

Data were independently extracted by two investigators using a standard data extraction checklist: 43 articles were included in this review, and 13 sedation scales were examined. The quality of the psychometric evidence for the Comfort Scale and Comfort Behaviour Scale was 'very good', with the Comfort Scale having a higher quality (total weighted scores, Comfort Scale = 17·3 and Comfort Behaviour Scale = 15·5).

CONCLUSIONS

We suggest that the scales be systematically and comprehensively tested in terms of development method, reliability, validation, feasibility and correlation with clinical outcome. The Comfort Scale and Comfort Behaviour Scale are useful tools for measuring sedation in paediatric patients.

RELEVANCE TO CLINICAL PRACTICE

Nursing staff should choose one subjective sedation scale that is suitable for assessing paediatric patients' depth of sedation. We recommend the Comfort Scale and Comfort Behaviour Scale as optimal choices if the clinical environment permits.

Skin conductance as a pain assessment tool during chest tube removal: An observational study

BACKGROUND

Skin conductance variability to assess pain has shown varying results. Skin conductance responses per second (SCR) during a standardized painful stimulus in awake adults may give further understanding of the method's validity. The purpose of this study was to validate the SCR with the visual analogue scale (VAS) for pain (P-VAS) and anxiety (A-VAS) during chest tube removal (CTR).

METHODS

Ninety-five patients receiving epidural or non-epidural treatment, scheduled for CTR, were studied. Pain or anxiety was considered when VAS > 30 mm; the SCR cut-off value reflecting pain was ≥0.2 SCR.

RESULTS

SCR values could not be recorded in eight cases before CTR, six cases during CTR and seven cases after CTR. CTR induced increases in SCR, P-VAS and A-VAS (p < 0.001). Seventy-seven percent of all pairs of P-VAS and SCR values were well-classified; P-VAS ≤ 30 mm and SCR < 0.2 or P-VAS > 30 mm and SCR ≥ 0.2. SCR obtained before CTR differentiates between patients with and without pain during CTR in all patients (p = 0.04) and in the subgroup of non-anxious patients (p = 0.02), but not in the subgroup of anxious patients. SCR obtained during CTR had similar values in patients with and without pain in all patients and in the subgroup of anxious patients, but in the subgroup of non-anxious patients SCR during CTR differentiates patients with and without pain (p = 0.009).

CONCLUSIONS

SCR increases during painful procedures. Preprocedural SCR may help predict reported pain in patients exposed to painful procedures. SCR during CTR differentiates between patients with and without pain only in non-anxious patients.

SIGNIFICANCE

Preprocedural SCR may help predict reported pain in patients exposed to painful procedures. Procedural SCR accuracy improves in a subgroup of non-anxious patients. P-VAS is influenced by anxiety different from SCR.

Pain rather than induced emotions and ICU sound increases skin conductance variability in healthy volunteers

BACKGROUND

Assessing pain in critically ill patients is difficult. Skin conductance variability (SCV), induced by the sympathetic response to pain, has been suggested as a method to identify pain in poorly communicating patients. However, SCV, a derivate of conventional skin conductance, could potentially also be sensitive to emotional stress. The purpose of the study was to investigate if pain and emotional stress can be distinguished with SCV.

METHODS

In a series of twelve 1-min sessions with SCV recording, 18 healthy volunteers were exposed to standardized electric pain stimulation during blocks of positive, negative, or neutral emotion, induced with pictures from the International Affective Picture System (IAPS). Additionally, authentic intensive care unit (ICU) sound was included in half of the sessions. All possible combinations of pain and sound occurred in each block of emotion, and blocks were presented in randomized order.

RESULTS

Pain stimulation resulted in increases in the number of skin conductance fluctuations (NSCF) in all but one participant. During pain-free baseline sessions, the median NSCF was 0.068 (interquartile range 0.013-0.089) and during pain stimulation median NSCF increased to 0.225 (interquartile range 0.146-0.3175). Only small increases in NSCF were found during negative emotions. Pain, assessed with the numeric rating scale, during the sessions with pain stimulation was not altered significantly by other ongoing sensory input.

CONCLUSION

In healthy volunteers, NSCF appears to reflect ongoing autonomous reactions mainly to pain and to a lesser extent, reactions to emotion induced with IAPS pictures or ICU sound.

Skin conductance in neonates suffering from abstinence syndrome and unexposed newborns

The aims of this study were to compare the skin conductance (SC) of newborns with opiate-induced neonatal abstinence syndrome (NAS) to that of unexposed newborns and to evaluate the potential of SC readings to detect distress in the context of NAS objectively. The SC of 12 newborns with NAS and 12 unexposed newborns was measured at nine specific times during their first 6 weeks of life. The number of SC fluctuations per second (NSCF/s), the amplitude of SC fluctuation, and the mean level of SC were recorded and analyzed. The SC of newborns treated for symptoms of NAS differed significantly from the SC of unexposed newborns with regard to the NSCF/s (p = 0.04). With the mean level of SC, we observed an interaction between groups over time (p value for interaction = 0.02). With increasing postnatal age, we observed higher values in all three SC parameters.

CONCLUSION

The NSCF/s and the mean level of SC appear to be suitable to reflect the distress of newborns suffering from NAS. As it is known that the sensitivity of SC increases with the level of stress experienced, its potential to indicate elevated stress levels in infants with NAS should be investigated in future studies evaluating different therapy regimens.

WHAT IS KNOWN

• Skin conductance is a result of the filling of palmar and plantar sweat glands innervated by the sympathetic nervous system • Skin conductance can be used as a measure of stress and pain in newborns What is New: • Skin conductance of newborns with neonatal abstinence syndrome (NAS) differs significantly from the SC of non-substance-exposed newborns during the first 6 weeks of life • Skin conductance appears to reflect the increased distress of infants with NAS.

The clinimetric properties of the COMFORT scale: A systematic review

The COMFORT scale is a measurement tool to assess distress, sedation and pain in nonverbal paediatric patients. Several studies have described the COMFORT scale, but no formal assessment of the methodological quality has been undertaken. Therefore, we performed a systematic review to study the clinimetric properties of the (modified) COMFORT scale in children up to 18 years. We searched Central, CINAHL, Embase, Medline, PsycInfo and Web of Science until December 2014. The selection, data extraction and quality assessment were performed independently by two reviewers. Quality of the included studies was appraised using the COSMIN checklist. We found 30 studies that met the inclusion criteria. Most participants were ventilated children up to 4 years without neurological disorders. The results on internal consistency and interrater reliability showed values of >0.70 in most studies, indicating an adequate reliability. Construct validity resulted in correlations between 0.68 and 0.84 for distress, between 0.42 and 0.94 for sedation and between 0.31 and 0.96 for pain. The responsiveness of the (modified) COMFORT scale seems to be adequate. The quality of the included studies ranged from poor to excellent. The COMFORT scale shows overall an adequate reliability in providing information on distress, sedation and pain. Construct validity varies from good to excellent for distress, from moderate to excellent for sedation, and from poor to excellent for pain. The included studies were clinically and methodologically heterogeneous, hampering firm conclusions. WHAT DOES THIS REVIEW ADD?: An in-depth assessment of the clinimetric properties of the COMFORT scale. The COMFORT scale shows overall an adequate reliability in providing information on distress, sedation and pain. Construct validity varies from good to excellent for distress, from moderate to excellent for sedation, and from poor to excellent for pain.

Preterm infants' behaviors and skin conductance responses to nurse handling in the NICU

Stress response patterns are indicative of the neonate's unique ability to cope with environmental demands and can be evaluated through autonomic and behavioral response parameters.

OBJECTIVE

To characterize stress responses during tactile stimulation to standard nurse handling in the NICU, and their association with severity of illness in preterm infants.

METHODS

Thirty preterm neonates were studied at postnatal day 4-5 during standard nurse caregiving. Heart rate (HR), respiratory rate (RR), skin conductance responses per second (SCR/s), and NIDCAP® stress behaviors were recorded before and during care. Non-parametric tests were used to assess differences from before to during care. Pearson's correlations were used to determine the association of biological and behavioral variables to the score for neonatal acute physiology (SNAP), a severity of illness index.

RESULTS

HR, RR, SCR/s and NIDCAP® behaviors (motor and attentional cues, and ability to self-console) increased from before to during the care (p < 0.01). NIDCAP® behaviors showed a significant negative association to the SNAP score (R = -0.45, p < 0.05).

CONCLUSIONS

HR, RR, SCR/s and NIDCAP® behaviors significantly increased during care. NIDCAP® stress behaviors were influenced by the severity of illness of the infant, while SCR/s was not influenced by severity of illness.

Assessing pain objectively: the use of physiological markers

Pain diagnosis and management would benefit from the development of objective markers of nociception and pain. Current research addressing this issue has focused on five main strategies, each with its own advantages and disadvantages. These encompass: (i) monitoring changes in the autonomic nervous system; (ii) biopotentials; (iii) neuroimaging; (iv) biological (bio-) markers; and (v) composite algorithms. Although each strategy has shown areas of promise, there are currently no validated objective markers of nociception or pain that can be recommended for clinical use. This article introduces the most important developments in the field and highlights shortcomings, with the aim of allowing the reader to make informed decisions about what trends to watch in the future.

Assessment of pain in critically ill children. Is cutaneous conductance a reliable tool?

PURPOSE

The purpose of this study is to assess the usefulness and accuracy of skin conductance (SC) as a tool to evaluate the level of sedation and pain in pediatric critical patients during painful procedures and to compare it with hemodynamic variables, clinical scales, and bispectral index (BIS).

MATERIALS AND METHODS

This is a prospective observational study in 61 critical children undergoing invasive procedures. Hemodynamic data (heart rate and arterial blood pressure), clinical scales punctuation (Ramsay, COMFORT, and numeric rating pain scales), BIS, and the number of fluctuations of SC per second were collected before, during, and at the end of the procedure.

RESULTS

The mean age of the patients was 42.9 (range, 1 month to 16 years). Seventy-two point six percent were postcardiac surgery patients. Nonmuscle-relaxed patients showed a moderate increase in heart rate (P = .02), numeric rating pain scales (P = .03), and Ramsay scale (P = .002). The number of fluctuations of SC per second increased significantly during the procedure (basal, 0.1; maneuver, 0.2; P = .015), but it never reached the level considered as pain or stress nor did it precede clinical scales or BIS. None of the variables studied showed a significant change during the procedure in muscle-relaxed patients.

CONCLUSIONS

Skin conductance was not found to be more sensitive or faster than clinical scales for the assessment of pain or stress in critical children undergoing painful procedures. Skin conductance was not useful in muscle-relaxed children.

Monitoring depth of anesthesia: from consciousness to nociception. A window on subcortical brain activity

Anesthesia results from several inhibitor processes, which interact to lead to loss of consciousness, amnesia, immobility, and analgesia. The anesthetic agents act on the whole brain, the cortical and subcortical areas according to their receptor targets. The conscious processes are rather integrated at the level of the cortical neuronal network, while the nonconscious processes such as the nociception or implicit memory require subcortical processing. A reliable and meaningful monitoring of depth of anesthesia should provide assessment of these different processes. Besides the EEG monitoring which gives mainly information on cortical anesthetic effects, it would be relevant to have also a subcortical feedback allowing an assessment of nociception. Several devices have been proposed in this last decade, to give us an idea of the analgesia/nociception balance. Up to now, most of them are based on the assessment of the autonomic response to noxious stimulation. Among the emerging clinical devices, we can mention those which assess vascular sympathetic response (skin conductance), cardiac and vascular sympathetic response (surgical pleth index), parasympathetic cardiac response (analgesia nociception index), and finally the pupillometry which is based on the assessment of the pupillary reflex dilatation induced by nociceptive stimulations. Basically, the skin conductance might be the most adapted to assess the stress in the awake or sedated neonate, while the performances of this method appear disappointing under anesthesia. The surgical pleth index is still poorly investigated in children. The analgesia nociception index showed promising results in adults, which have to be confirmed, especially in children and in infants, and lastly pupillometry, which can be considered as reliable and reactive in children as in adults, but which is still sometimes complicated in its use.

Reward and motivation in pain and pain relief

Pain is fundamentally unpleasant, a feature that protects the organism by promoting motivation and learning. Relief of aversive states, including pain, is rewarding. The aversiveness of pain, as well as the reward from relief of pain, is encoded by brain reward/motivational mesocorticolimbic circuitry. In this Review, we describe current knowledge of the impact of acute and chronic pain on reward/motivation circuits gained from preclinical models and from human neuroimaging. We highlight emerging clinical evidence suggesting that anatomical and functional changes in these circuits contribute to the transition from acute to chronic pain. We propose that assessing activity in these conserved circuits can offer new outcome measures for preclinical evaluation of analgesic efficacy to improve translation and speed drug discovery. We further suggest that targeting reward/motivation circuits may provide a path for normalizing the consequences of chronic pain to the brain, surpassing symptomatic management to promote recovery from chronic pain.

Assessment of atropine-sufentanil-atracurium anaesthesia for endotracheal intubation: an observational study in very premature infants

Background

Premedication before neonatal intubation is heterogeneous and contentious. The combination of a short acting, rapid onset opioid with a muscle relaxant is considered suitable by many experts. The purpose of this study was to describe the tolerance and conditions of intubation following anaesthesia with atropine, sufentanil and atracurium in very premature infants.

Methods

Monocentric, prospective observational study in premature infants born before 32 weeks of gestational age, hospitalised in the NICU and requiring semi-urgent or elective intubation. Intubation conditions, heart rate, pulse oxymetry (SpO₂), arterial blood pressure and transcutaneous PCO₂ (TcPCO₂) were collected in real time during 30 minutes following the first drug injection. Repeated physiological measurements were analysed using mixed linear models.

Results

Thirty five intubations were performed in 24 infants with a median post conceptional age of 27.6 weeks and a median weight of 850 g at the time of intubation. The first attempt was successful in 74% and was similar for junior (75%) and senior (74%) operators. The operator rated conditions as “excellent” or “good” in 94% of intubations. A persistent increase in TcPCO₂ as compared to baseline was observed whereas other vital parameters showed no significant variations 5, 10, 15 and 30 minutes after the first drug injection. Eighteen (51%) desaturations (SpO2 less than or equal to 80% for more than 60 seconds) and 2 (6%) bradycardia (heart rate less than100 bpm for more than 60 seconds) were observed.

Conclusion

This drug combination offers satisfactory success rate for first attempt and intubation conditions for the operator without any significant change in heart rate and blood pressure for the patient. However it is associated with frequent desaturations and a possible persistent hypercapnia. SpO₂ and PCO₂ can be significantly modified during neonatal intubation and should be cautiously followed in this high-risk population.

Does skin-to-skin contact reduce stress during diaper change in preterm infants?

BACKGROUND

Skin-to-skin contact reduces pain response in preterm infants subjected to minor painful procedures, such as heel lance. Diaper change is a procedure performed several times daily in hospitalized preterm infants. Routine care giving tasks such as diaper change may be stressful for the infant.

AIMS

The purpose of this study was to investigate whether diaper change induces stress and if skin-to-skin contact could reduce such stress, measured by changes in skin conductance.

STUDY DESIGN

This was a randomized crossover pilot study in 19 preterm infants with gestational age between 28 and 34 weeks. The diaper change procedure was done twice in each infant, once during skin-to-skin contact, and once in incubator or bed with the mother present.

OUTCOME MEASURES

During diaper change heart rate (HR), peripheral oxygen saturation (SpO2), and changes in skin conductance (SC) peaks per sec, using the Skin Conductance Algesimeter (SCA), were registered.

RESULTS

The mean SC peaks/sec increased/decreased significantly under/after change of diapers which thereby underpins that this is a stressful procedure for the preterm infant. Skin-to-skin contact (SSC) entails significantly lower stress levels (p<0.05) compared to diaper changed in an incubator/bed measured by the SCA.

CONCLUSIONS

Diaper change is a stressful procedure for preterm infants and may be ameliorated by skin-to-skin contact.

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.

Comparison of skin conductance measurements and subjective pain scores in children with minor injuries

AIM

Objective measures of perceived pain may aid clinicians in decision-making regarding analgesia. This study aimed to assess the effectiveness of an algesimeter to assess the pain response of children to minor injury when compared with self-report.

METHODS

A commercially available skin conductance algesimeter was used to record pain in children presenting with a minor injury to a district general hospital. The recordings were compared with self-reported pain scores using the Wong-Baker FACES(®) Pain Rating Scale.

RESULTS

Sixty-seven children below 16 years of age (36 females, 53.7%, mean age 11.9 years, standard deviation 3.1 years) were assessed. There was a significant correlation between self-reported pain and number of fluctuations in skin conductance per second for girls (r = 0.325, p = 0.027), but not for boys (r = 0.160, p = 0.194). There was no significant association between self-reported pain and number of fluctuation in skin conductance per second and patient age.

CONCLUSION

There was a significant correlation between self-reported pain and the number of fluctuations in skin conductance in girls, but not boys. There may be a number of reasons for this gender variation, including difficulty in rating pain and lack of sensitivity in the pain rating scale.

Skin conductance as a marker of pain in infants of different gestational age

AIMS

To assess the use of skin conductance as an objective measure of pain in infants of different gestational age. A second aim was to investigate the relationship between skin conductivity and selected physiological and behavioural variables (oxygen saturation, heart rate and behavioural state).

METHODS

Infants were divided according to gestational age into the following 3 groups; group A: 25+0-31+6 weeks (13 infants), group B: 32+0-35+6 weeks (25 infants), group C: 36+0-41+6 weeks (19 infants). The pain stimulus was blood sampling.

RESULTS

The most sensitive parameter for describing changes in skin conductance related to pain was peak per second. No other parameter correlated with the physiological variables chosen. The results showed that the inability to determine basal skin conductance is a crucial disadvantage to practical application. The lack of correlation between conductance parameters and gestational age is surprising.

CONCLUSION

We conclude that the Peak per Second is the best parameter for evaluating skin conductance in infants and it is not influenced by gestational age. Peaks per Second correlate only with Prechtl's Scale of behavioural state and not with the physiological parameters chosen.

COMFORT behaviour scale and skin conductance activity: what are they really measuring?

AIM

To assess how efficiently the COMFORT behaviour scale measures acute pain in neonates, in comparison with skin conductance activity, a validated measure of pain and stress.

METHODS

Images of 36 newborns were analysed before, during and after painful heel pricks to measure glucose levels and compared with skin conductance activity variables.

RESULTS

Scale indicators and skin conductance variables were sensitive to changes in the periods 'during-before' and 'during-after' (Wilcoxon's test, p < 0.01). Significant values were found between all scale indicators and number of waves for Kendall's coefficient (p < 0.05), although responses differed when it came to how long they took to increase and correlations varied from fair to moderate (r < 0.6). Facial tension was more closely related to 15 sec after the painful event, while crying and calmness were more closely related to the later intervals (30 and 180 sec).

CONCLUSION

All scale indicators were related to skin conductance activity in all periods, indicating pain perception. Facial tension was the most efficient indicator, while others varied in performance after painful events and possibly indicated stress after trauma. These results are discussed from a phenomenological approach and in an anxiety paradigm.

Assessment of pain in the neonate

Accurate pain assessment in preterm and term neonates in the neonatal intensive care unit (NICU) is of vital importance because of the high prevalence of painful experiences in this population, including both daily procedural pain and postoperative pain. Over 40 tools have been developed to assess pain in neonates, and each NICU should choose a limited number of pain assessment tools for different populations and contexts. Only two pain assessment tools have a metric adjustment to account for differences of pain assessment in prematurity. Preterm neonates do not display behavior and physiologic indicators of pain as reliably and specifically as full term infants, and preterm infants are vulnerable to long term sequelae of painful experiences. "Brain-oriented" approaches for more objective measurement of pain in neonates may become available in the future. In the meantime, neonatal pain assessment tools need to be taught, implemented, and their ongoing use optimized to form a consistent, reproducible basis for the safe and effective treatment of neonatal pain.

Monitoring of pain and stress in an infant with asphyxia during induced hypothermia: a case report

The purpose of this article was to study an infant who suffered from asphyxia undergoing induced hypothermia with regard to (1) describe the pain and stress as measured by physiological variables skin conductance algesimeter (SCA) and pain rating scales, (2) the correlation between SCA and pain rating scales, and (3) how temperature cycles in the cooling blanket affect the response of the sympathetic nervous system as measured by the SCA and physiological variables. A single prospective case study was used for this article. Data were recorded every 15 minutes for 96 hours. Each observation was categorized according to treatment phase: cooling 0 to 72 hours, rewarming, and controlled normal temperature up to 96 hours. Structured observations were carried out and all nursing care was documented. In addition, 5 periods with no other nursing interventions were identified in which data were recorded every minute for analysis. Skin conductance algimetry showed a variable response during treatment. During cooling, 68% of the 15-minute periods, signs of stress and pain were recorded. During rewarming, the corresponding figure was 83%. During the time sequences with normal temperature, 89% of the periods were associated with stress and pain. During 80% of the nursing procedures, the SCA showed stress and pain. There was no correlation between the pain-rating scales and SCA. When the cooling blanket temperature was lower than core temperature, the infant had more stress and pain according to SCA (P < .001) and an increase in heart rate and blood pressure (P < .001). In infants during induced hypothermia, SCA seem to detect pain and stress. Future evaluation of SCA for the detection of pain and stress during hypothermia treatment is necessary. Pain-rating scales do not appear reliable in this case report.

Skin conductance variations compared to ABC scale for pain evaluation in newborns

OBJECTIVES

To validate spontaneous skin conductance variations as a specific reliable mean to measure pain in full-term healthy newborns during heel stick, comparing it with the ABC scale. To compare oral sucrose to wrapping effectiveness for non-pharmacological analgesia during the same procedure.

METHOD

All recruited newborns (n = 158) underwent a heel stick for metabolic screening at 48 h of life with non-pharmacological analgesia by oral sucrose (group A) or wrapping (group B) according to randomization. Their pain was estimated by ABC scale score (standard method) and measured by skin conductance variations.

RESULTS

A positive correlation was founded between peaks per sec measure and ABC score (rs = 0.303, p < 0.005). ABC score in group A was lower than in group B (p < 0.001). Difference in mean ABC score among newborn subgroups treated by different nurses was not statistically significant for wrapping while it was significant for sucrose (p = 0.001).

CONCLUSIONS

Skin conductance measurement device is a reliable method to evaluate pain. Novel technological devices may be a useful support to clinical observation in this field. Oral sucrose is more effective than wrapping in reducing pain. Operators should be well periodically re-trained in performing non pharmacological analgesia during minor procedure on newborns.

Pain assessment in children undergoing venipuncture: the Wong-Baker faces scale versus skin conductance fluctuations

The aim of this study was to evaluate the efficacy of the subjective Wong–Baker faces pain rating scale (WBFS) and of the objective skin conductance fluctuation (SCF) test in assessing pain in children undergoing venipuncture. One-hundred and fifty children (aged 5–16 years) entered the study. All underwent venipuncture at the antecubital fossa to collect blood specimens for routine testing in the same environmental conditions. After venipuncture, the children indicated their pain intensity using the WBFS, whereas the number of SCFs was recorded before, during and after venipuncture. So, pain level was measured in each child with WBFS and SCF. We found that the level of WBFS-assessed pain was lower in all children, particularly those above 8 years of age, than SCF-assessed pain (p < 0.0001). Moreover, the number of SCFs was significantly higher during venipuncture than before or after venipuncture (p < 0.0001). At multivariate regression analysis, age and previous experience of venipuncture influenced the WBFS (β = −1.81, p < 0.001, and β = −0.86, p < 0.001, respectively) but not SCFs. In conclusion, although both procedures can be useful for research and clinical practice, our findings show that WBFS was affected by age and previous venipuncture, whereas SCF produced uniform data. If verified in other studies, our results should be taken into account when using these tools to evaluate pain in children.