Bispectral index versus COMFORT score to determine the level of sedation in paediatric intensive care unit patients: a prospective study

2022 Society of Critical Care Medicine Clinical Practice Guidelines on Prevention and Management of Pain, Agitation, Neuromuscular Blockade, and Delirium in Critically Ill Pediatric Patients With Consideration of the ICU Environment and Early Mobility

RATIONALE

A guideline that both evaluates current practice and provides recommendations to address sedation, pain, and delirium management with regard for neuromuscular blockade and withdrawal is not currently available.

OBJECTIVE

To develop comprehensive clinical practice guidelines for critically ill infants and children, with specific attention to seven domains of care including pain, sedation/agitation, iatrogenic withdrawal, neuromuscular blockade, delirium, PICU environment, and early mobility.

DESIGN

The Society of Critical Care Medicine Pediatric Pain, Agitation, Neuromuscular Blockade, and Delirium in critically ill pediatric patients with consideration of the PICU Environment and Early Mobility Guideline Taskforce was comprised of 29 national experts who collaborated from 2009 to 2021 via teleconference and/or e-mail at least monthly for planning, literature review, and guideline development, revision, and approval. The full taskforce gathered annually in-person during the Society of Critical Care Medicine Congress for progress reports and further strategizing with the final face-to-face meeting occurring in February 2020. Throughout this process, the Society of Critical Care Medicine standard operating procedures Manual for Guidelines development was adhered to.

METHODS

Taskforce content experts separated into subgroups addressing pain/analgesia, sedation, tolerance/iatrogenic withdrawal, neuromuscular blockade, delirium, PICU environment (family presence and sleep hygiene), and early mobility. Subgroups created descriptive and actionable Population, Intervention, Comparison, and Outcome questions. An experienced medical information specialist developed search strategies to identify relevant literature between January 1990 and January 2020. Subgroups reviewed literature, determined quality of evidence, and formulated recommendations classified as "strong" with "we recommend" or "conditional" with "we suggest." Good practice statements were used when indirect evidence supported benefit with no or minimal risk. Evidence gaps were noted. Initial recommendations were reviewed by each subgroup and revised as deemed necessary prior to being disseminated for voting by the full taskforce. Individuals who had an overt or potential conflict of interest abstained from relevant votes. Expert opinion alone was not used in substitution for a lack of evidence.

RESULTS

The Pediatric Pain, Agitation, Neuromuscular Blockade, and Delirium in critically ill pediatric patients with consideration of the PICU Environment and Early Mobility taskforce issued 44 recommendations (14 strong and 30 conditional) and five good practice statements.

CONCLUSIONS

The current guidelines represent a comprehensive list of practical clinical recommendations for the assessment, prevention, and management of key aspects for the comprehensive critical care of infants and children. Main areas of focus included 1) need for the routine monitoring of pain, agitation, withdrawal, and delirium using validated tools, 2) enhanced use of protocolized sedation and analgesia, and 3) recognition of the importance of nonpharmacologic interventions for enhancing patient comfort and comprehensive care provision.

Grade of sedation in the critically ill pediatric patient and its correlation with sociodemographic and clinical variables. Multicentre COSAIP study

AIMS

To determine the grade of sedation in the critically ill paediatric patient using Biespectral Index Sensor (BIS) and to analyse its relationship with sociodemographic and clinical patient variables.

METHODS

Observational, analytical, cross-sectional and multicentre study performed from May 2018 to January 2020 in 5 Spanish paediatric critical care units. Sex, age, reason for admission, presence of a chronic pathology, type and number of drugs and length of stay were the sociodemographic and clinical variables registered. Furthermore, the grade of sedation was assessed using BIS, once per shift over 24 h.

RESULTS

A total of 261 paediatric patients, 53.64% of whom were male, with a median age of 1.61 years (0.35-6.55), were included in the study. Of the patients, 70.11% (n = 183) were under analgosedation and monitored using the BIS sensor. A median of BIS values of 51.24 ± 14.96 during the morning and 50.75 ± 15.55 during the night were observed. When comparing BIS values and sociodemographic and clinical paediatric variables no statistical significance was detected.

CONCLUSIONS

Despite the limitations of the BIS, investigations and the present study show that BIS could be a useful instrument to assess grade of sedation in critically ill paediatric patients. However, further investigations which determine the sociodemographic and clinical variables involved in the grade of paediatric analgosedation, as well as studies that contrast the efficacy of clinical scales like the COMFORT Behaviour Scale-Spanish version, are required.

Current State of Analgesia and Sedation in the Pediatric Intensive Care Unit

Critically ill pediatric patients often require complex medical procedures as well as invasive testing and monitoring which tend to be painful and anxiety-provoking, necessitating the provision of analgesia and sedation to reduce stress response. Achieving the optimal combination of adequate analgesia and appropriate sedation can be quite challenging in a patient population with a wide spectrum of ages, sizes, and developmental stages. The added complexities of critical illness in the pediatric population such as evolving pathophysiology, impaired organ function, as well as altered pharmacodynamics and pharmacokinetics must be considered. Undersedation leaves patients at risk of physical and psychological stress which may have significant long term consequences. Oversedation, on the other hand, leaves the patient at risk of needing prolonged respiratory, specifically mechanical ventilator, support, prolonged ICU stay and hospital admission, and higher risk of untoward effects of analgosedative agents. Both undersedation and oversedation put critically ill pediatric patients at high risk of developing PICU-acquired complications (PACs) like delirium, withdrawal syndrome, neuromuscular atrophy and weakness, post-traumatic stress disorder, and poor rehabilitation. Optimal analgesia and sedation is dependent on continuous patient assessment with appropriately validated tools that help guide the titration of analgosedative agents to effect. Bundled interventions that emphasize minimizing benzodiazepines, screening for delirium frequently, avoiding physical and chemical restraints thereby allowing for greater mobility, and promoting adequate and proper sleep will disrupt the PICU culture of immobility and reduce the incidence of PACs.

Grade of sedation in the critically ill paediatric patient and its correlation with sociodemographic and clinical variables. Multicentre COSAIP study

AIMS

To determine the grade of sedation in the critically ill paediatric patient using Biespectral Index Sensor (BIS) and to analyse its relationship with sociodemographic and clinical patient variables.

METHODS

Observational, analytical, cross-sectional and multicentre study performed from May 2018 to January 2020 in 5 Spanish paediatric critical care units. Sex, age, reason for admission, presence of a chronic pathology, type and number of drugs and length of stay were the sociodemographic and clinical variables registered. Furthermore, the grade of sedation was assessed using BIS, 11per shift over 24hours.

RESULTS

A total of 261 paediatric patients, 53.64% of whom were male, with a median age of 1.61 years (0.35-6.55), were included in the study. Of the patients, 70.11% (n=183) were under analgosedation and monitored using the BIS sensor. A median of BIS values of 51.24±14.96 during the morning and 50.75±15.55 during the night were observed. When comparing BIS values and sociodemographic and clinical paediatric variables no statistical significance was detected.

CONCLUSIONS

Despite the limitations of the BIS, investigations and the present study show that BIS could be a useful instrument to assess grade of sedation in critically ill paediatric patients. However, further investigations which determine the sociodemographic and clinical variables involved in the grade of paediatric analgosedation, as well as studies that contrast the efficacy of clinical scales like the COMFORT Behaviour Scale-Spanish version, are required.

[Validity and reliability of the Niño Jesús Hospital procedural sedation-analgesia scale of the under deep sedation-analgesia]

INTRODUCTION

The procedural sedation scale of the Niño Jesús Hospital (Madrid) (SSPNJH) has not been validated.

PATIENTS AND METHODS

A prospective analytical study was conducted in 2 hospitals on patients ≥ 6 months undergoing invasive procedures using sedation-analgesia with propofol or midazolam and fentanyl. All were monitored using the bispectral index (BIS). Videos were made of each procedure, which were then edited and randomised. A total of 150 videos were rated by four observers using the SSPNJH, the sedation scale of the University of Michigan (UMSS), and the Ramsay Scale (SR). These observers were blinded to the BIS, and at the time of drug administration. To assess test-retest reliability, 50 of the initial 150 randomly selected videos were re-assessed.

RESULTS

The study included a total of 65 patients. The within-observer agreement was high (ρ = 0.793). The SSPNJH gave a good interobserver reliability when compared with the UMSS (ICC = 0.88) and the SR (ICC = 0.86), and there was none with the BIS. Internal consistency was moderate (α = 0.68). Construct validity was demonstrated by changes in scores after administering sedatives (p < 0.0001). The SSPNJH had a very low correlation with the BIS (r = -0.166), and a moderate correlation with the UMSS (r = 0.497) and the SR (r = 0.405). As regards the applicability, this scale has been used in two hospitals in five different areas by four professionals of different categories.

CONCLUSIONS

The SSPNJH is valid, reliable and applicable for sedation monitoring in invasive procedures under deep sedation-analgesia in paediatric patients. The SSPNJH has worse properties than the UMSS and the SR.

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.

Pharmacological sedation management in the paediatric intensive care unit

Objective

This review addresses sedation management on paediatric intensive care units and possible gaps in the knowledge of optimal sedation strategies. We present an overview of the commonly used sedatives and their pharmacokinetic and pharmacodynamic considerations in children, as well as the ongoing studies in this field. Also, sedation guidelines and current sedation strategies and assessment methods are addressed.

Key findings

This review shows that evidence and pharmacokinetic data are scarce, but fortunately, there is an active research scene with promising new PK and PD data of sedatives in children using new study designs with application of advanced laboratory methods and modelling. The lack of evidence is increasingly being recognized by authorities and legislative offices such as the US Food and Drug Administration (FDA) and European Medicines Agency (EMA).

Conclusion

The population in question is very heterogeneous and this overview can aid clinicians and researchers in moving from practice-based sedation management towards more evidence- or model-based practice. Still, paediatric sedation management can be improved in other ways than pharmacology only, so future research should aim on sedation assessment and implementation strategies of protocolized sedation as well.

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.

Bispectral Index in Evaluating Effects of Sedation Depth on Drug-Induced Sleep Endoscopy

OBJECTIVE

To evaluate the effect of sedation depth on drug-induced sleep endoscopy (DISE).

METHODS

Ninety patients with obstructive sleep apnea (OSA) and 18 snorers underwent polysomnography and DISE under bispectral index (BIS)-guided propofol infusion at two different sedation levels: BIS 65-75 (light sedation) and 50-60 (deep sedation).

RESULTS

For the patients with OSA, the percentages of velopharynx, oropharynx, hypopharynx, and larynx obstructions under light sedation were 77.8%, 63.3%, 30%, and 33.3%, respectively. Sedation depth was associated with the severity of velopharynx and oropharynx obstruction, oropharynx obstruction pattern, tongue base obstruction, epiglottis anteroposterior prolapse and folding, and arytenoid prolapse. In comparison, OSA severity was associated with the severity of velopharynx obstruction, severity of oropharynx obstruction, and arytenoid prolapse (odds ratio (95% confidence interval); 14.3 (4.7-43.4), 11.7 (4.2-32.9), and 13.2 (2.8-62.3), respectively). A good agreement was noted between similar DISE findings at different times and different observers (kappa value 0.6 to 1, respectively). A high percentage of arytenoid prolapse (46.7% among the patients with OSA under light sedation) was noted.

CONCLUSIONS

Greater sedative depth increased upper airway collapsibility under DISE assessment. DISE under BIS-guided propofol infusion, and especially a level of 65-75, offers an objective and reproducible method to evaluate upper airway collapsibility. Some findings were induced by drug sedation and need careful interpretation. Specific arytenoid prolapse patterns were noted for which further investigations are warranted.

CLINICAL TRIALS REGISTRATION

http://www.clinicaltrials.gov, identifier: NCT01100554.

COMMENTARY

A commentary on this article appears in this issue on page 965.

Sedation monitoring during open muscle biopsy in children by Comfort Score and Bispectral Index - a prospective analysis

BACKGROUND

Open muscle biopsies in children are generally performed under general anesthesia. Alternatively, deep sedation and analgesia may be required.

OBJECTIVES

The aim of our study was to compare the Bispectral Index (BIS) and Comfort Score (CS) with respect to their clinical significance for sedation/analgesia in children undergoing open muscle biopsy.

METHODS

Thirty pediatric patients subjected to open muscle biopsy for diagnosis of their underlying disease were prospectively enrolled. Sedation/analgesia was performed in all patients using remifentanil and propofol. The patients were simultaneously monitored using the CS and BIS.

RESULTS

All sedations and muscle biopsies were performed uneventfully. The CS and BIS were significantly correlated (R = 0.589; P < 0.01). Receiver operating characteristic (ROC) analysis revealed an area under the curve (AUC) of 0.918 with a maximum cut-off point of BIS 70.5 (sensitivity 0.9; specificity 0.785) for adequate sedation. Sensitivity of 100% was achieved at BIS 60. Accordingly, all patients with BIS ≤60 had CS within the target range of 10-14. The BIS showed substantial intra- and interindividual variability (30 points and 58 points, respectively) during sedation, whereas CS varied only within close ranges during sedation. In 25 patients, sedatives were reduced according to low BIS values (<60). No unintended anesthesia awareness was noted during the study period.

CONCLUSION

Bispectral Index provides an additional helpful tool to guide sedation/analgesia in minor surgical procedures in children. BIS values ≤60 correlated with sufficient depth of sedation and prevented unintended awareness. Additionally, BIS measurement allowed for distinct regulation of depth of sedation without prolonged sedation/analgesia due to unintended overdose.

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.

A comparison of gradual sedation levels using the Comfort-B scale and bispectral index in children on mechanical ventilation in the pediatric intensive care unit

Objective

Compare the scores resulting from the Comfort-B scale with the bispectral index in children in an intensive care unit.

Methods

Eleven children between the ages of 1 month and 16 years requiring mechanical ventilation and sedation were simultaneously classified based on the bispectral index and the Comfort-B scale. Their behavior was recorded using digital photography, and the record was later evaluated by three independent evaluators. Agreement tests (Bland-Altman and Kappa) were then performed. The correlation between the two methods (Pearson correlation) was tested.

Results

In total, 35 observations were performed on 11 patients. Based on the Kappa coefficient, the agreement among evaluators ranged from 0.56 to 0.75 (p<0.001). There was a positive and consistent association between the bispectral index and the Comfort-B scale [r=0.424 (p=0.011) to r=0.498 (p=0.002)].

Conclusion

Due to the strong correlation between the independent evaluators and the consistent correlation between the two methods, the results suggest that the Comfort-B scale is reproducible and useful in classifying the level of sedation in children requiring mechanical ventilation.

The SNAP index does not correlate with the State Behavioral Scale in intubated and sedated children

BACKGROUND

Ensuring appropriate levels of sedation for critically ill children is integral to pediatric critical care. Traditionally, clinicians have used subjective scoring tools to assess sedation levels. The SNAP II uses dual frequency processed electroencephalography to evaluate brain activity and may provide an objective assessment of sedation levels.

OBJECTIVE

This study attempts to find an objective method to monitor sedation in critically ill pediatric patients. We compared the SNAP II, a processed electroencephalography device, with the State Behavioral Scale (SBS), a subjective sedation scoring tool. We hypothesize that the SNAP II correlates with the SBS and has less observer bias.

METHODS

This was an IRB approved prospective, observational study. Patients receiving intravenous sedation while being mechanically ventilated were enrolled after informed consent. After the SNAP II monitoring electrodes were attached, blinded bedside nurses assessed sedation levels using the SBS. SNAP indices were collected and compared with SBS scores to determine correlation.

RESULTS

We compared 417 paired data points from 15 patients using Pearson's correlation and least squares means to determine correlation between the SBS and SNAP indices. No correlation was observed. Using covariance model patterning for repeated measures to adjust for covariates again showed no correlation.

CONCLUSION

The SNAP index does not correlate with SBS scores in our pediatric intensive care unit (PICU). Its use cannot be recommended to measure levels of sedation in our population. Future research should continue to explore objective ways of measuring sedation in critically ill children.

Optimal sedation in pediatric intensive care patients: a systematic review

PURPOSE

Sedatives administered to critically ill children should be titrated to effect, because both under- and oversedation may have negative effects. We conducted a systematic review to examine reported incidences of under-, optimal, and oversedation in critically ill children receiving intensive care.

METHODS

A systematic literature search using predefined criteria was performed in PubMed and Embase to identify all articles evaluating level of sedation in PICU patients receiving continuous sedation. Two authors independently recorded: study objective, study design, sample size, age range, details of study intervention (if applicable), sedatives used, length of sedation, sedation scale used, and incidences of optimal, under-, and oversedation as defined in the studies.

RESULTS

Twenty-five studies were included. Two studies evaluated sedation level as primary study outcome; the other 23 as secondary outcomes. Together, these studies investigated 1,163 children; age range, 0-18 years. Across studies, children received many different sedative agents and sedation level was assessed with 12 different sedation scales. Optimal sedation was ascertained in 57.6 % of the observations, under sedation in 10.6 %, and oversedation in 31.8 %.

CONCLUSIONS

This study suggests that sedation in the PICU is often suboptimal and seldom systematically evaluated. Oversedation is more common than undersedation. As oversedation may lead to longer hospitalization, tolerance, and withdrawal, preventing oversedation in pediatric intensive care deserves greater attention.

A review of the utility of EEG depth of anaesthesia monitors in the paediatric intensive care environment

OBJECTIVES

This paper aims to bring together current evidence regarding the use of depth of anaesthesia monitors (DoAM) as objective measures of sedation for paediatric intensive care (PIC) patients.

BACKGROUND

Delivering appropriate dosages of sedative agents, to individual PIC patients, is important to reduce the many risks of over- or under-sedation. Although based on adult anaesthesia, DoAMs could offer increased objectivity to the titration of sedative agents for children in PIC. This article synthesises the current available evidence from studies investigating DoAM use in the PIC environment.

METHOD

Literature regarding DoAM use in PIC was reviewed, from 1996 and August 2011, after EMBASE, PubMed, CINAHL and ProQuest Dissertation & Theses Database were searched using key search terms.

FINDINGS

Fourteen original research articles addressing sedation assessment using DoAMs in PIC were identified. The main findings were that DoAMs generally have a moderate or poor correlation with sedation scores and their performance varies in varying clinical settings. DoAMs do not make reliable conclusions about depth of sedation of individual PIC children, and can be influenced by children's age.

CONCLUSION

Evidence to support DoAMs in the PIC setting is currently not sufficient to advocate their routine use in clinical practice.

Monitoring sedation in the critically ill child

Sedation is an essential part of the management of the critically ill child, and its monitoring must be individualised and continuous in order to adjust drug doses according to the clinical state. There is no ideal method for evaluating sedation in the critically ill child. Haemodynamic variables have not been found to be useful. Clinical scales are useful when sedation is moderate, but are limited by their subjective nature, the use of stimuli, and the impossibility of evaluating profoundly sedated patients or those receiving neuromuscular blocking drugs; in addition, many of these scales have not been evaluated in children. The COMFORT scale is the most appropriate, as it was designed and validated for critically ill children requiring mechanical ventilation. Electroencephalography-derived methods permit continuous monitoring, provide an early indication of changes in the level of sedation, and facilitate a rapid adjustment of medication. However, these methods were designed and validated for patients under anaesthesia and their results cannot be fully extrapolated to the critically ill patient; in addition, some of them have not been validated in small children and there is still little experience in critically ill children. The main indications for the use of these methods are in patients with deep sedation and/or neuromuscular blockade. The bispectral index is the most widely used method at the present time. Analysis and comparison of the efficacy of the different methods for evaluating sedation in the critically ill child is required.

Analysis of bispectral index and middle latency auditory-evoked potentials parameters in critically ill children

To study the parameters of the bispectral index and middle latency auditory-evoked potentials in critically ill children. We performed a prospective, observational study in 81 critically ill children categorized into two levels of sedation (moderate and deep) and three age groups (<1, 1-6, and >6 months). The parameters of the bispectral index and middle latency auditory-evoked potentials studied were the signal quality index, suppression ratio, total power, spectral edge frequency, electromyographic activity, and suppression ratio. Suppression rates were higher in children younger than 1 month than in older children and were also higher in deep sedation. Total power and spectral edge frequency increased with age. Electromyographic activity was higher in moderate sedation. Spectral edge frequency and suppression rates change with age and level of sedation. These variations are a consequence of the electroencephalographic structure at young ages and are secondary to the higher proportion of slow waves in deep states of sedation.

Assessment of the level of sedation in children after cardiac surgery

BACKGROUND

There is no reference method for the evaluation of the level of sedation in children after cardiac surgery. The utility of the bispectral index and middle latency auditory evoked potentials has not been evaluated.

METHODS

The bispectral index, middle latency auditory evoked potentials, Ramsay scale, and COMFORT scale were used for assessment of the level of sedation in critically ill children after cardiac surgery and other surgical procedures. The measurements with these four methods were recorded simultaneously once a day for five days. The level of sedation was categorized in two levels, moderate or deep, according to the values obtained from each method. Correlations and agreements among the methods and the best bispectral index and middle latency auditory evoked potential values that discriminated between the two levels of sedation were calculated.

RESULTS

Thirty-two children after cardiac surgery were included in the study, together with eighteen children after other surgical procedures who formed the control group. In each group, the correlation and agreement between the four methods varied between moderate and good. In the cardiac surgery patients, when the level of sedation was determined by the Ramsay scale, the best values of bispectral index and middle latency auditory evoked potentials that discriminated between the two levels of sedation were 63.5 and 37.5, respectively, and these values predicted the level of sedation correctly in 84.4% of the patients with each method.

CONCLUSIONS

Bispectral index and middle latency auditory evoked potentials could be useful to assess the level of sedation in children after cardiac surgery.

Assessing sedation in critically ill children by bispectral index, auditory-evoked potentials and clinical scales

OBJECTIVE

To evaluate the correlation and agreement between the bispectral index (BIS), middle latency auditory-evoked potential index (AEP index), Ramsay scale (RS) and COMFORT scale (CS) for evaluation of the level of sedation in critically ill children.

DESIGN

Prospective observational study.

SETTING

Pediatric critical care unit.

PATIENTS

Seventy-seven critically ill children receiving sedation and mechanical ventilation.

MEASUREMENTS AND RESULTS

Simultaneous recording of BIS, AEP index, RS and CS were performed once a day, for a maximum of 5 days. Two levels of sedation were categorized: light-moderate versus deep-very deep. Correlations between methods were determined using Spearman rank correlation test and the agreement using Cohen's Kappa test. The correlation and agreement between the four methods was moderate-to-good. Correlation was not found in paralyzed children. There was no correlation between the four methods and the heart rate or blood pressure, or with the type or dose of sedative medication. Receiver-operating characteristic (ROC) analysis revealed best discrimination between light-moderate and deep-very deep sedation at BIS and AEP index values of 63.5 and 33.5 when the level of sedation was classified by the RS, and at BIS and AEP index values of 67 and 37.5, respectively, when the level of sedation was classified by the CS.

CONCLUSION

There is a moderate-to-good correlation and agreement of BIS and AEP index with the clinical scales in critically ill children without neuromuscular blockade. BIS and AEP index could be useful to evaluate the level of sedation in critically ill children with and without neuromuscular blockade.

Bispectral Index asymmetry and COMFORT score in paediatric intensive care patients

BACKGROUND

The Bispectral Index (BIS) monitor has been suggested as a potential tool to measure depth of sedation in paediatric intensive care unit (PICU) patients. The primary aim of our observational study was to assess the difference in BIS values between the left and right sides of the brain. Secondary aims were to compare BIS and COMFORT score and to assess change in BIS with tracheal suctioning.

METHODS

Nineteen ventilated and sedated PICU patients had paediatric BIS sensors applied to either side of their forehead. Each patient underwent physiotherapy involving tracheal suctioning. Their BIS data and corresponding COMFORT score, assessment as by their respective nurses, were recorded before, during, and after physiotherapy.

RESULTS

Seven patients underwent more than one physiotherapy session; therefore, 28 sets of data were collected. The mean BIS difference values (and 95% CI) between left BIS and right BIS for pre-, during, and post-physiotherapy periods were 9.2 (5.9-12.5), 15.8 (11.9-19.7), and 7.5 (5.2-9.7), respectively. Correlation between mean BIS, left brain BIS, and right brain BIS to COMFORT score was highly significant (P<0.001 for all three) during the pre- and post-physiotherapy period, but less so during the stimulated physiotherapy period (P=0.044, P=0.014, and P=0.253, respectively).

CONCLUSIONS

A discrepancy between left and right brain BIS exists, especially when the patient is stimulated. COMFORT score and BIS correlate well between light and moderate sedation.

Can analysis of the bispectral index prove helpful when monitoring titration of doses of midazolam and ketamine for sedation during paediatric cardiac catheterization

OBJECTIVE

We investigated the use of the bispectral index for monitoring sedation during cardiac catheterization. The scores for the bispectral index may not reflect correct values in children, but may be helpful during titration of sedatives such as midazolam and ketamine.

METHODS

We conducted a prospective randomized clinical trial in 126 patients scheduled for cardiac catheterization in a teaching hospital. They ranged in age from 4 months to 15 years. In 66 patients, sedation was performed without use of the bispectral index, while the index was used in the other 60 patients. The data collected included heart rate, mean arterial pressure, respiratory rate, saturation of oxygen, amount of sedatives, awakening time and adverse effects. We subdivided the patients into age-related groups for each parameter.

RESULTS

The demographic data were not statistically different. Monitoring with the bispectral index in those aged from 1 to 3 years revealed use of lower doses of midazolam, at 2.09 mg per kg per hr, with standard deviation of 0.36, and similarly lowers doses of ketamine, at 2.07 mg per kg per hr, with standard deviation of 0.22, the values in those not monitored being 2.93, with standard deviation of 0.45, and 2.96 with standard deviation of 0.51 respectively, these difference being statistically significant (p = 0.001 and p = 0.04, respectively). In those aged from 3 to 6 years of age, dosage of midazolam was 2.09, with deviation of 0.36, and of ketamine 1.78, with deviation of 0.27, following use of the bispectral index, compared to 2.89 with deviation of 0.28, and 2.62 with deviation of 0.69 respectively, when the bispectral index was not used, these again being significant differences (p = 0.033 and p = 0.04). The requirements for respiratory support and adverse effects were also significantly lower when using the bispectral index (p less than 0.05). No significant difference was found regarding dosages at the ages of 4 months to 1 year, and 6 to 15 years. The awakening time, however, was shorter with use of the index in those aged from 1 to 6 years.

CONCLUSIONS

When using the bispectral index for monitoring sedation during catheterization in children, we noted decreased need for doses of midazolam and ketamine, a lower need for respiratory support and less adverse effects.

Monitoring the anaesthetic depth in children - an update

PURPOSE OF REVIEW

There are several commercially available electroencephalogram-derived devices for monitoring anaesthesia depth. This article reviews all published studies describing their use in children; first assessing studies of performance in measuring anaesthesia depth in observational, physiological studies and then describing relevant outcome studies. There is also a brief discussion of why they might be useful, what physiological problems may arise and what the reader should be wary of in the methodology of these studies. The subject is approached from a clinical perspective.

RECENT FINDINGS

There are several physiological studies suggesting that for older children the bispectral index, entropy, Narcotrend index, cerebral state index and A-line ARX index all change with induction of anaesthesia, and have reasonable correlations with doses of anaesthetic agent. There is consistent evidence that the performances are substantially poorer in infants. Some of these devices have been demonstrated to reduce anaesthesia drug consumption and hasten recovery in older children.

SUMMARY

The bispectral index is the most widely studied, but at this stage there is no evidence to suggest any one device is substantially superior to any other. There may be a role emerging for their use in older children, but their use in infants cannot be supported.

"Between the fixed and the changing": examining and comparing reliability and validity of 3 sedation-agitation measuring scales

The goal of the study was to compare the reliability and validity of 3 Sedation Agitation Scale. Two nurses and a physician conducted 130 observations simultaneously. They found an excellent interrater reliability in the Richmond Agitation Sedation Scale (r>0.86), and high correlations between the Richmond Agitation Sedation Scale and the Sedation Agitation Scale and Visual Analog Scale scales (r=0.92, r=0.85). The research findings will help to assert Richmond Agitation Sedation Scale as a daily assessment tool in the intensive care unit, and it will pave the way for construction a sedation protocol according to the Richmond Agitation Sedation Scale level.

The correlation between the richmond agitation–sedation scale and bispectral index during dexmedetomidine sedation

BACKGROUND AND OBJECTIVES

The primary objective of sedation in the critically ill patient is to achieve security and comfort. The routine use of standardized and validated sedation scales and monitors are needed. The Richmond agitation sedation scale has been used but some patients cannot be evaluated with subjective assessment tools such as the Richmond agitation sedation scale because they lack motor responsiveness due to therapeutic paralysis or because they are receiving deep sedation. We aimed to assess the correlation of bispectral index with Richmond agitation sedation scale during dexmedetomidine sedation and evaluate the use of the bispectral index in monitoring the levels of sedation in intensive care patients.

METHODS

This was a single centre, prospective, clinical study. Eleven mechanically-ventilated critically ill patients, aged 17-82 (50.09 +/- 17.76; mean +/- SD) yr, 3 males and 8 females, APACHE II score 12.63 +/- 3.90, SOFA score 3.27 +/- 1.73 were enrolled in the study. Patients received a dexmedetomidine infusion of 1 microg kg-1 over 10 min followed by a maintenance infusion of 0.5 microg kg-1 h-1 for 8 h. Sedation was assessed using the Richmond agitation sedation scale and bispectral index monitoring. Heart rate, blood pressure, respiratory rate and SPO2 were monitored. Wilcoxon signed rank sum test and Spearman's rank correlation analysis were used for statistical analysis.

RESULTS

The variation of Richmond agitation sedation scale score was between 0.9 and -1.7 bispectral index varied from 65 to 75. Significant correlations between Richmond agitation sedation scale and bispectral index values were found in this study. (r = 0.900; P = 0.0001)

CONCLUSIONS

Richmond agitation sedation scale levels significantly correlated with bispectral index values during dexmedetomidine sedation in critically ill patients requiring mechanical ventilation in the intensive care unit.

[Which sedation scale should be used in the paediatric intensive care unit? A comparative prospective study]

OBJECTIVES

To compare pain and sedation assessments by nurses undertaken with the Objective Pain Scale (OPS) and a Visual Analogue Scale (VAS) to the current reference scale for paediatric intensive care that is the COMFORT scale. To compare the unmodified COMFORT scale to a COMFORT "behaviour" scale which does not include physiologic items. To evaluate the ease of use of these scales.

METHODS

This prospective observational comparative study was carried out in children aged 1 year or older who were admitted in an intensive care unit. At 2 to 3 time points within 24 hours, a pain sedation assessment was carried out by the nurse in charge of the child with COMFORT scale, OPS and VAS. Correlation tests were used to compare the scores of each scale.

RESULTS

Nurses recorded 55 assessments in 20 children. Correlation studies showed a poor correlation between OPS, VAS and the COMFORT scale (Spearman's r=0.54 and 0.53 respectively) and a strong correlation between the COMFORT scale and the COMFORT "behaviour" scale (Spearman's r=0.96). The COMFORT behaviour scale was the most frequently fully completed scale.

CONCLUSION

Among the 3 scales compared to the COMFORT scale in this study, the COMFORT "behaviour" scale was the only one to show a strong correlation and it also seemed to be the easiest to use.

The use of bispectral index monitors in paediatric intensive care

The bispectral index (BIS) is a processed neurophysiological electroencephalographic parameter that may be used to evaluate the depth of sedation in critically ill children. Triltsch and colleagues attempted to correlate BIS scores with a commonly used clinical sedation scoring system. They were able to demonstrate good correlation during deep sedation and in cases where the electrical impedance of the BIS electrodes was lowest. Studies have shown only moderate degrees of correlation between BIS scores and clinical sedation scoring systems. There is currently insufficient evidence to recommend routine monitoring of BIS scores in critically ill children.