Sedation assessment: easier said than done!

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.

Actigraphy: analyzing patient movement

BACKGROUND

Actigraphic data during simulated participant movements were evaluated to differentiate among patient behavior states.

METHODS

Arm and leg actigraphic data were collected on 30 volunteers who simulated 3 behavioral states (calm, restless, agitated) for 10 minutes; counts of observed participant movements (head, torso, extremities) were documented.

RESULTS

The mean age of participants was 34.7 years, and 60% were female. Average movement was significantly different among the states (P < .0001; calm [mean = .48], restless [mean = 2.16], agitated [mean = 3.75]). Mean actigraphic measures were significantly different among states for both arm (P < .0001; calm [mean = 6.8], restless [mean = 28.5], agitated [mean = 52.6]) and leg (P < .0001; calm [mean = 3.5], restless [mean = 18.7], agitated [mean = 37.7]).

CONCLUSION

Distinct levels of behavioral states were successfully simulated. Actigraphic data can provide an objective indicator of patient activity over a variety of behavioral states, and these data may offer a standard for comparison among these states.

The effects of music on physiological responses and sedation scores in sedated, mechanically ventilated patients

AIMS AND OBJECTIVES

A pilot study designed as future randomised controlled trial was carried out to determine the effects of music on physiological responses and sedation scores in sedated, mechanically ventilated patients.

BACKGROUND

Mechanically ventilated ICU patients, even when receiving intravenous sedatives, may experience stress and anxiety. One possible intervention to reduce stress and anxiety is listening to music.

DESIGN

A randomised controlled trial design with repeated measures was used.

METHODS

Data were collected over a six-month period in 2006. Twenty subjects were randomly assigned to either the experimental or control group. Subjects in the experimental group listened to music three times for 30 minutes over two days; subjects in the control group undertook three 30 minute rest periods. Physiological effects of music on systolic, diastolic and mean arterial blood pressure and heart and respiratory rate were assessed. Sedation scores were also measured.

RESULTS

Physiological parameters did not show a significant difference between the groups. Patients in the experimental group showed significantly higher Ramsay (sedation) scores than patients in the control group after the first session. The higher scores indicate that patients were less responsive to external stimuli.

CONCLUSION

Our results suggest that listening to music leads to higher sedation scores in sedated, mechanically ventilated ICU patients. No significant decreases in physiological parameters were observed. Listening to music showed no negative changes in the condition of these patients. Future research should focus on the use of other measures, such as stress hormones, to assess stress in sedated, mechanically ventilated ICU patients.

RELEVANCE TO CLINICAL PRACTICE

For the sedated, mechanically ventilated ICU patient, the benefit of music may lie in the associated (deeper) level of sedation that is achieved, which in turn may make the patient less susceptible to stress and anxiety.

Assessment of the reliability and validity of the Comfort Scale for adult intensive care patients

OBJECTIVE

This study sought to evaluate the use of the Comfort Scale (CS), originally developed for children, in sedated adults at intensive care units.

METHODS

Comfort and sedation were assessed in a convenience sample of 88 adult intensive-care patients receiving mechanical ventilation, using 5 instruments (the Ramsay Scale, Sedation Agitation Scale, Richmond Agitation Sedation Scale, Glasgow Coma Scale, and CS).

RESULTS

Reliability (internal consistency according to Cronbach's α, .60 to .66; inter-rater reliability, r = .81; test-retest, r = .21 to .31) and validity (criterion validity with other scales, κ = .49 to .74, for construct validity and sensitivity) were determined. The range of children's comfort (i.e., 17 to 26) was different from that in adults (i.e., 16 to 20).

CONCLUSIONS

Results partially support the use of the CS among adults in intensive care units, with some minor adjustments.

Reliable assessment of sedation level in routine clinical practice by adding an instruction to the Ramsay Scale

OBJECTIVE

The level of sedation in mechanically ventilated patients is most often assessed with the Ramsay Scale. Its reliability, however, has never been evaluated in a large group of professionals using the Ramsay Scale in daily clinical practice, while differences in interpretations among professionals have been indicated. We developed a written stepwise instruction to optimize the inter-observer reliability of the Ramsay Scale within a large group of Intensive Care (IC) nurses.

DESIGN

Reliability study.

SETTING

The Intensive Care Cardiology (ICC) and the Intensive Care Thoracic surgery (ICT) units of a university hospital.

PATIENTS AND PARTICIPANTS

The study population comprises randomly selected mechanically ventilated patients and IC nurses with a bachelor's degree in Nursing and an IC certification. In total 2x105 Ramsay measures were performed in 45 patients by 24 nurses.

MEASUREMENT AND RESULTS

Analysis of 105 paired Ramsay scores showed an almost perfect agreement between observers (weighted K (Kw)=0.90). In both ICC patients and ICT patients, agreement between Ramsay scores was high (Kw=0.95 and Kw=0.86, respectively).

CONCLUSION

By using a written stepwise instruction with the Ramsay Scale, the inter-observer reliability of the level of sedation measurements, performed in daily clinical practice within a large team of IC nurses, proved to be almost perfect.

State Behavioral Scale: a sedation assessment instrument for infants and young children supported on mechanical ventilation

OBJECTIVE

To develop and test the reliability and validity of the State Behavioral Scale for use in describing sedation/agitation levels in young intubated patients supported on mechanical ventilation.

DESIGN

: In this prospective, psychometric evaluation, pairs of trained pediatric critical care nurse evaluators simultaneously and independently assessed a convenience sample of pediatric intensive care unit patients along eight state/behavioral dimensions and a numeric rating scale (NRS) of 0 (extremely sedated) to 10 (extremely agitated). The eight dimensions were derived from the sedation/agitation literature and expert opinion and included respiratory drive, response to ventilation, coughing, best response to stimulation, attentiveness to careprovider, tolerance to care, consolability, and movement after consoled, each with 3-5 levels.

SETTING

An 18-bed pediatric medical-surgical intensive care unit and 26-bed pediatric cardiovascular intensive care unit in a university-affiliated academic children's hospital.

PATIENTS

A total of 91 intubated mechanically ventilated patients 6 wks to 6 yrs of age provided a median of two observations (interquartile range, 1-3) for a total of 198 sets of observations. Excluded were postoperative patients or those receiving neuromuscular blockade.

INTERVENTIONS

Patients were observed for 1 min, and then incremental levels of stimulation were applied until patient response. After 2 mins of consoling, the state behavioral assessment and NRS were completed.

MEASUREMENTS

Weighted kappa and intraclass coefficients were generated to assess interrater reliability of the eight dimension and NRS ratings. Distinct state behavior profiles were empirically identified from the dimension ratings using hierarchical cluster analysis using a squared Euclidean distance measure and between-groups linkage. Construct validity of these profiles was assessed by comparing group mean NRS scores using one-way analysis of variance.

MAIN RESULTS

Weighted kappa scores for all 198 dimension ratings ranged from .44 to .76, indicating moderate to good interrater reliability. The intraclass coefficient of .79 was high for NRS ratings. Cluster analysis revealed five distinct state profiles, with mean NRS ratings of 1.1, 2.5, 4.0, 5.3, and 7.6, all of which differed significantly from each other (F = 75.8, p < .001), supporting the profiles' construct validity.

CONCLUSIONS

Based on empirically derived state behavior profiles, we have constructed the State Behavioral Scale to allow systematic description of the sedation-agitation continuum in young pediatric patients supported on mechanical ventilation. Further studies including prospective validation and describing the effect of State Behavioral Scale implementation on clinical outcomes, including the quality of sedation and length of mechanical ventilation, are warranted.

Sedation issues in transportation of acutely and critically ill patients

Recognizing how the transport setting affects the patient, and the required therapies to support the patient, is a critical aspect of patient care. Transporting an acutely or critically ill patient, be they neonatal, pediatric, maternal, adult medical, or trauma patients, requires an in-depth understanding of the application of sedation in the transport setting, both therapeutic and adverse effects, and how to manage those effects for the best patient outcome.