Correlation between the Sedation-Agitation Scale and the Bispectral Index in ventilated patients in the intensive care unit.
ABSTRACT Oversedation masks neurologic changes and increases mortality/morbidity, whereas undersedation risks prolonged stress mobilization and patient injury. In situations such as deep sedation/analgesia, the Bispectral Index (BIS) has potential use as an adjunct to clinical assessment of sedation to help determine depth of sedation. Determining the correlation between clinical and BIS measures of sedation will help to determine the correct role of BIS in intensive care unit (ICU) practice settings.
To evaluate the correlation between the clinical assessment of sedation using the Sedation-Agitation Scale (SAS) and the assessment using BIS in ventilated and sedated ICU patients.
ICU patients requiring mechanical ventilation and sedation were monitored using the SAS and BIS. Nurses initiated event markers with BIS at the time of SAS assessment but were blinded to BIS scores.
Data were collected on 40 subjects generating 209 paired readings. Moderate positive correlation between BIS and SAS values was shown with a Spearman Rank coefficient r value of .502 and an r(2) of .252 (P < .0001). Wide ranges of BIS scores were observed, especially in very sedated patients. Strong positive correlation was noted between BIS and electromyography with an r value of .749 (P < .0001). Age and gender significantly influenced BIS/SAS correlations.
In situations in which the clinical assessment is equivocal, BIS monitoring may have an adjunctive role in sedation assessment. BIS values should be interpreted with caution, however, because electromyography activity and other factors seem to confound BIS scores. More research is necessary to determine the role of BIS monitoring in ICU practice.
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ABSTRACT: BACKGROUND: Pain assessment is an immense challenge for clinicians, especially in the context of the intensive care unit, where the patient is often unable to communicate verbally. Several methods of pain assessment have been proposed to assess pain in this environment. These include both behavioural observation scales and evaluation of physiological measurements such as heart rate and blood pressure. Although numerous validation studies pertaining to behavioural observation scales have been published, several limitations associated with using these measures for pain assessment remain. Over the past few years, researchers have been interested in the use of the bispectral index monitoring system as a proxy for the evaluation of encephalography readings to assess the level of anesthesia and, potentially, analgesia. OBJECTIVES: To synthesize the main studies exploring the use of the bispectral index monitoring system for pain assessment, to guide future research in adults under sedation in the intensive care unit. METHOD: The EMBASE, Medline, CINAHL and PsycINFO databases were searched for studies published between 1996 and 2013 that evaluated the use of the bispectral index in assessing pain. RESULTS: Most studies conclude that nociceptive stimulation causes a significant increase in the bispectral index and revealed the importance of controlling certain confounding variables such as the level of sedation. DISCUSSION: Further studies are needed to clearly demonstrate the relationship between nociceptive stimuli and the bispectral index, as well as the specificity of the bispectral index in detecting pain.Pain research & management: the journal of the Canadian Pain Society = journal de la societe canadienne pour le traitement de la douleur 07/2014; 20(1). · 1.39 Impact Factor
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ABSTRACT: To determine the optimal use and indications of electroencephalography (EEG) in critical care management of acute brain injury (ABI). An electronic literature search was conducted for articles in English describing electrophysiological monitoring in ABI from January 1990 to August 2013. A total of 165 studies were included. EEG is a useful monitor for seizure and ischemia detection. There is a well-described role for EEG in convulsive status epilepticus and cardiac arrest (CA). Data suggest EEG should be considered in all patients with ABI and unexplained and persistent altered consciousness and in comatose intensive care unit (ICU) patients without an acute primary brain condition who have an unexplained impairment of mental status. There remain uncertainties about certain technical details, e.g., the minimum duration of EEG studies, the montage, and electrodes. Data obtained from both EEG and EP studies may help estimate prognosis in ABI patients, particularly following CA and traumatic brain injury. Data supporting these recommendations is sparse, and high quality studies are needed. EEG is used to monitor and detect seizures and ischemia in ICU patients and indications for EEG are clear for certain disease states, however, uncertainty remains on other applications.Neurocritical Care 09/2014; 21(S2). DOI:10.1007/s12028-014-0022-8 · 2.60 Impact Factor
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ABSTRACT: In our daily practice in intensive care unit, one of the “cornerstones” is to achieve adequate sedation for every patient. Intensive care unit (ICU) patients are often sedated, and a good hypnotic monitoring is important to assure an optimal level of sedation for every patient. Sedation monitoring can be achieved using subjective or objective methods. The most recent recommendations on management of sedation were published by Critical Care Medicine in January 2013. They recommend the use of subjective methods as the primary method to monitor sedation, with the use of objective methods only in paralyzed and comatose patients, in whom subjective methods cannot be used. Unfortunately in these last recommendations, the objective methods of sedation monitoring are listed without indicating any of them as the best method actually available to assure an adequate sedation. The aim of our study is to review the characteristics of each objective method of sedation monitoring, in order to understand which is the most appropriate in the current state. We found that several objective methods are adequate to monitor the level of sedation in paralyzed or comatose patients, although the data needs to be considered with caution, Bispectral Index (BIS) is suggested as the best method for monitoring sedation in most studies.