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

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.

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.

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.

Intraoperative nociception-antinociception monitors: A review from the veterinary perspective

OBJECTIVE

To review monitors currently available for the assessment of nociception-antinociception in veterinary medicine.

DATABASES USED

PubMed, Web of Science and Google Scholar. The results were initially filtered manually based on the title and the abstract.

CONCLUSIONS

The provision of adequate antinociception is difficult to achieve in veterinary anaesthesia. Currently, heart rate and arterial blood pressure are used to monitor the response to a noxious stimulus during anaesthesia, with minimum alveolar concentration-sparing effect and stress-related hormones used for this purpose in research studies. However, since none of these variables truly assess intraoperative nociception, several alternative monitoring devices have been developed for use in humans. These nociceptive-antinociceptive monitoring systems derive information from variables, such as electroencephalography, parasympathetic nervous system (PNS) response, sympathetic nervous system response and electromyography. Several of these monitoring systems have been investigated in veterinary medicine, although few have been used to assess intraoperative nociception in animals. There is controversy regarding their effectiveness and clinical use in animals. A nociceptive-antinociceptive monitoring system based on the PNS response has been developed for use in cats, dogs and horses. It uses the parasympathetic tone activity index, which is believed to detect inadequate intraoperative nociception-antinociception balance in veterinary anaesthesia. Nonetheless, there are limited published studies to date, and cardiovascular variables remain the gold standard. Consequently, further studies in this area are warranted.

Non-pharmacological interventions for pain management in adult victims of trauma: a scoping review protocol

OBJECTIVE

This scoping review aims to map non-pharmacological interventions for reducing acute pain for adult victims of trauma.

INTRODUCTION

Acute pain, as a consequence of either a pathological or traumatic event or even due to invasive and non-invasive healthcare procedures, is highly prevalent in critically ill patients. However, specific acute pain as a direct consequence of trauma is one of the least studied areas of acute pain.

INCLUSION CRITERIA

This scoping review will consider studies on adult victims of trauma, aged 18 years or over, in prehospital emergency care, emergency departments and trauma centers. All studies that focus on non-pharmacological interventions designed to reduce acute pain, implemented and evaluated by health professionals in any form, duration, frequency and intensity, will be considered.

METHODS

An initial search of PubMed and CINAHL will be undertaken, followed by a second search for published and unpublished studies from 2000 to the present in major healthcare related electronic databases. Studies in English, French, Spanish and Portuguese will be included. Data extraction will be performed independently by two reviewers in tabular form and include details about the interventions, populations, study methods and outcomes of interest. A narrative synthesis will accompany the results and will describe how they relate to the review objectives.

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.

Paracetamol and morphine for infant and neonatal pain; still a long way to go?

INTRODUCTION

Pharmacologic pain management in newborns and infants is often based on limited scientific data. To close the knowledge gap, drug-related research in this population is increasingly supported by the authorities, but remains very challenging. This review summarizes the challenges of analgesic studies in newborns and infants on morphine and paracetamol (acetaminophen). Areas covered: Aspects such as the definition and multimodal character of pain are reflected to newborn infants. Specific problems addressed include defining pharmacodynamic endpoints, performing clinical trials in this population and assessing developmental changes in both pharmacokinetics and pharmacodynamics. Expert commentary: Neonatal and infant pain management research faces two major challenges: lack of clear biomarkers and very heterogeneous pharmacokinetics and pharmacodynamics of analgesics. There is a clear call for integral research addressing the multimodality of pain in this population and further developing population pharmacokinetic models towards physiology-based models.