Several reports tell a high incidence of intensive care delirium. To develop strategies to prevent this complication validated instruments are needed. The Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) is widely used. A binary result diagnoses delirium. The Neelon and Champagne (NEECHAM) Confusion Scale recently has been validated for use in the ICU and has a numeric assessment. This scale allows the patients to be classified in four categories: non-delirious at risk confused and delirious. In this chew over we investigated the results of the NEECHAM scale in comparison with the CAM-ICU.
The CAM-ICU showed a 19.8% incidence of delirium. The NEECHAM measure detected incidence rates of 20.3% for delirious. 24.4% for confused. 29.7% for at assay and 25.6% for normal patients. The majority of the positive CAM-ICU patients were detected by the NEECHAM scale. The sensitivity of the NEECHAM measure was 87% and the specificity was 95%. The positive predictive determine and the negative predictive value were 79% and 97% respectively. The diagnostic capability in cardiac surgery patients proved to be lower than in other patients.
Delirium is a well-known acute syndrome in the intensive care unit (ICU). A physical cause induces a fluctuating disturbance of the cognitive processes in the hit. The patient encounters periods of inattention in combination with disorganized thinking or a changed level in consciousness. The affect is observed as a hypoactive hyperactive or mixed write. The hyperactive type is the least frequent one although it is the easiest to sight [
]. To develop strategies to prevent or cure this complication validated instruments for diagnosing screening and quantifying are needed.
(DSM) criteria []. The development of internationally accepted diagnostic tools created the opportunity to analyse and verify the onset and process of intensive care delirium without the need for consulting a psychiatrist. The Confusion Assessment Method (CAM) [
] is a well-validated and frequently used tool. The scale was designed to be used by non-psychiatric physicians and trained researchers. Because the patient in intensive care is not always able to communicate verbally the CAM was adapted for screening intubated or artificially ventilated patients. The Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) [] is widely accepted as the standard in intensive care delirium assessment. This assessment tool was based on the DSM-IV criteria and diagnoses the delirious state by a yes or no say to a four-point algorithm (Appendix 1). A positive say to this algorithm indicates delirium and a negative answer indicates a normal cognitive express. Nevertheless the results of this measure are limited by its binomial come of the evaluation of delirium and the fact that it is a one-point-in-time assessment.
The Neelon and Champagne (NEECHAM) Confusion Scale [] was developed a few years later based on daily nursing practice. In this scale the nurses' 24-hour assessment of the level of processing information the level of behavior and the physiological instruct rate the patient on a 30 to 0 scale classifying him or her in one of four categories (Appendix 2). The cutoff values of 30 to 27 for 'non-delirious' (normal). 26 or 25 for 'at risk' and 24 to 20 for 'early to mild confusion' (mild confusion) were standardized. Validation for delirium against the DSM-III-R criteria was performed for the scores 19 to 0 ('moderate to severe confusion') in the original development of the scale. Consequently the delirious express can be assessed and changes in the cognitive answer of the patient can be monitored. The NEECHAM scale is reliable for the detection of delirium by nurses in the general hospital population [
]. In this chew over we investigated the NEECHAM scale in comparison with the CAM-ICU in a non-intubated intensive care population.
All patients were admitted to the intensive compassionate department of the Antwerp University Hospital (625 beds). The department has a capacity of 39 beds and admits more than 2,000 patients each year. This department is divided in five units of seven or nine beds. These units are preferentially but not exclusively specialized in treating cardiosurgical surgical or medical intensive care patients. Patients are admitted to a separated lay or an individual room with a clock visual and auditive contact with the staff and the possibility to comprehend to the communicate or watch television. Most of the patients have a window with visible daylight. All non-intubated patients with a score of at least 10 on the Glasgow Coma measure a minimum age of 18 years and a stay of at least 24 hours before the first assessment in the ICU were included. Patients of all units were included resulting in a mixed intensive compassionate population in this study.
A trained nurse researcher included the patients once daily in the morning. First the patient was assessed with the NEECHAM measure without calculating the results and immediately afterwards with the CAM-ICU. A evaluate with the CAM-ICU was regarded as positive for delirium scoring positive on the algorithm. The NEECHAM scale categories were used to classify the patient. A test advance of lower than 20 (moderate to severe confusion) is defined as 'delirium'. Each patient scoring positive for delirium at least once on the CAM-ICU or the NEECHAM measure was identified as delirious for the calculation of the incidence rates.
The included patients were classified in three categories of admittance: cardiac surgery non-cardiac surgery and internal medicine. Age gender and Simplified Therapeutic Intervention Scoring System 28 (TISS 28) score [] were collected for all included patients. The mean TISS 28 advance was calculated for each patient based on all daily values obtained during the stay in the ICU. The Acute Physiology And Chronic Health Evaluation (APACHE) II score is not validated for calculating the severity of disease or assay prediction for a cardiac surgery assort. This advance was calculated at the first day of admittance for the internal care for and the non-cardiac surgery groups only.
To analyse the studied scales diagnostic descriptives were calculated in a two-by-two table for all paired assessments. Sensitivity specificity negative predictive value and positive predictive value of the NEECHAM measure refer to the CAM-ICU as the reference assessment drive [
]. Subgroup analysis for age gender length of be and category of admittance was performed based on the most severe CAM-ICU and NEECHAM scale score of each patient.
The Statistical Package for the Social Sciences 14.0 (SPSS Inc.. Chicago. IL. USA) was used for the statistical analysis. The different categories of admittance were compared using the chi-square test the independent
test and the one-way analysis of variance where applicable. Correlations were calculated using the Pearson correlation coefficient. Significance was calculated on a 0.05 level.
The protocol of this study was presented to the ethical come in of the University Hospital of Antwerp where it was approved. An informed consent was requested from the patient or his or her legal representative where appropriate.
A first group of patients was included in July to August 2006 and a back up group in February to March 2007 resulting in a consecutive consume of 172 patients and a total of 599 paired observations. The mixed intensive care population was composed of 23% cardiac surgery. 37% non-cardiac surgery and 40% internal medicine patients. The convey age of the included population was 60 years (range 20 to 90) and 59% were male. The mean APACHE II score was 21 (range 7 to 47) and the convey TISS 28 score was 29 (be 2 to 46) (Table ).
The incidence of delirium assessed with the CAM-ICU was 19.8% for the total population. The NEECHAM assessment showed 20.3% with delirium. 24.4% with 'mild confusion'. 29.7% as 'at risk' and 25.6% as 'normal' (evaluate ). Most of the patients scoring positive for delirium on the CAM-ICU were classified in the NEECHAM measure category diagnosing delirium. Almost a third of the patients scoring contradict on the CAM-ICU were positive on the NEECHAM scale most in the 'mild confusion' group and fewer in the delirious assort. All of the patients scoring 'normal' or 'at risk' on the NEECHAM scale were assessed as negative on the CAM-ICU (Table ).
Positive delirium observations were obtained for 39 patients on 183 delirious days. Consequently this resulted in a mean of 4.7 delirium days for each delirious patient ranging from 1 to 18 days. Most of these patients suffered one (23%) two (18%) or three (13%) delirious days. Most of the delirious patients (31%) were positive for the first measure within 3 days after admission to the ICU and 57% were positive for the first time after 4 days. Within 7 days. 77% of the delirious patients were positive for the first time.
= 172) showed similar results for the CAM-ICU and the NEECHAM measure. Both instruments agreed that there was no difference in the onset of delirium concerning age or gender (Table ). Both showed a trend toward a higher incidence for the internal medicine patients. The length of stay in the ICU was higher for the delirious patients (Table ). These results were significant regarding the CAM-ICU and the categories of the NEECHAM scale. Additionally the NEECHAM scale scores showed a positive correlation with the length of stay in days (
Each NEECHAM observation was compared with the paired CAM-ICU observation to reason the diagnostic descriptives (Figure ). Using the NEECHAM cutoff value of less than 20 ('severe confusion') test values were considered to be positive for delirium to calculate the diagnostic descriptives. The overall sensitivity was good but was lower in the cardiac surgery group (Figure ). The specificity showed good results overall and in the different categories of admittance. Due to the lower sensitivity in the cardiac surgery group the positive predictive value was poor for the assessment of this population but was higher in the other categories of admittance and was 79% overall. The negative predictive value was good overall and in the different categories of admittance.
In this study the incidence of delirium assessed with the NEECHAM measure (20.3%) was comparable to the results of the CAM-ICU (19.8%). The diagnostic descriptives of the NEECHAM measure showed good results. Additionally patients were classified in the different categories of the NEECHAM measure.
The research on intensive compassionate delirium has taken a giant step forward since the development of assessment tools. A scale diagnosing delirium seems reliable when development was based on the DSM criteria. Hence a confirmation by a psychiatrist is not necessary in daily practice. A gold standard for biological or physical tests however could be discussed []. A standard implies a level of perfection able to judge over all other tests. This perfection could hardly be attained by an individual assessing the patient.
Although the delirium assessment instruments undergo often been used in research the implementation as a standard medical or nursing screening tool has just started in clinical learn. The CAM-ICU the Intensive Care Delirium Checklist and the NEECHAM scale are available to check for delirium. Nowadays there seems to be no need for the development of new tools but the existing instruments should be studied thoroughly and refined to bring home the bacon a global understanding of the assessment of the delirium syndrome [].
The CAM-ICU was developed for physicians and researchers based on the DSM criteria [] but now is available to be used by intensive care nurses. The screening can be implemented in the daily nursing compassionate after limited training. The instrument is translated and validated in 10 different languages. Therefore the CAM-ICU usually is considered to be the 'gold standard' for the diagnosis of delirium. The incidence rates of delirium assessed with the CAM-ICU showed a wide range. Ely and colleagues [,] reported incidence rates of 83.3% and 87.0% in conscious medical or coronary care patients who were mechanically ventilated. McNicoll and colleagues [] detected 31.1% delirium in medical intensive compassionate patients older than 65 years and Balas and colleagues [] reported 28.3% in a surgical ICU. In our research. 19.8% of the mixed intensive care population developed delirium according to the CAM-ICU. The subgroup analysis of the internal medicine patients (Table ) open an incidence of 26.5% in our population but the other categories of patients developed less delirium. Our incidence rates assessed with the CAM-ICU be to be lower than those of the published reports. This could be explained by the absence of ventilated patients in our population. Moreover the architecture of the studied ICUs might compete a beneficial role in the prevention of delirium (for example the presence of visible daylight and a clock). Further research has to focus on the onset of delirium and the precipitating assay factors in the studied ICU.
The NEECHAM scale was developed as a nursing screening instrument for the early detection of delirium and was validated against DSM criteria for use in an ICU []. In this validation research. 19.4% delirium and 15.8% mild confusion rates were open in a medium-sized ICU of a general hospital. The population in our study had a similar incidence for delirium but a higher incidence for 'mild confusion'. A report of Csokasy and Pugh [] also using the NEECHAM scale showed a total advance of 47% for both categories taken together. The patients in their population (
= 19) were all older than 65 years and were admitted to an ICU of a smaller hospital. As already stated by Immers and colleagues [] the evaluation of the physiological condition may not be relevant to the delirium assessment of the patient in the ICU. Since there has been no investigate or validation study to affirm this suggestion the assessment of the physiological instruct will be retained as a basic element of this drive. Additionally further study is needed to alter and validate the NEECHAM measure for the delirium assessment of the intubated or the ventilated patient. Also a longitudinal study needs to inquire whether the numbered approach and the different categories of the NEECHAM scale have a predictive value against a binary come. Consequently the categories 'at assay' and 'mild confusion' could have an additional value. Preventive actions eventually could protect patients from becoming delirious. As Devlin and colleagues [] in their excellent analyse of delirium instruments for the ICU already remarked all evaluations are dichotomous and therefore do not decide delirium severity.
Besides the NEECHAM scale and the CAM-ICU the Intensive Care Delirium Checklist is a commonly used screening tool for the detection of delirium in the ICU []. Incidence rates of 19.2% and 31.8% were reported in an adult population in a mixed ICU [
]. Many items in this scale can also be scored by a nurse during daily practice. This eight-item scale also provides a numeric approach to the delirium assessment. Each item scoring positive gets one point. A score of four points was considered to detect 99% of the delirious patients. A definition of a population 'at risk' or with 'mild confusion' is not provided. A binary approach of the score was suggested. Given the four categories of the NEECHAM scale the last one creates more opportunities to classify the patient.
Four positive CAM-ICU patients scored 'mild confusion'. Five patients scoring contradict on the CAM-ICU scored delirious on the NEECHAM measure. Four of them had a borderline advance on the NEECHAM scale. One patient had a score of 14 on the NEECHAM scale and was assessed as negative for delirium on the CAM-ICU. This patient received propofol (through a continuous intravenous infusion pump) which possibly influenced the results. The NEECHAM scale proved to be a good delirium screening equip with a strong denial power. The specificity proved to be good in all categories. The diagnostic descriptives for the NEECHAM scale in the cardiac surgery group in differentiate to the results of the other categories of admittance were low.
Nurses are the first caregivers to observe the patient and to sight an altering cognitive function. The NEECHAM scale uses the daily observation skills of nurses and their standard 24-hour monitoring of a patient in the ICU. The CAM-ICU needs a short visual or auditive test. Both scales showing the same result in the diagnosis of delirium could be considered for implementation in the standard nursing observation or monitoring in the ICU. The focus in research on intensive care delirium should shift from possible treatments to early prevention of the syndrome [
]. The detection of patients in an early stage of confusion and the classification in categories could become an important advantage of the NEECHAM Confusion Scale [,]. Therefore a longitudinal study is needed.
Our study is limited by the size of the population in the different categories of admittance. Each category could be the subject of a further chew over. Both studied scales were validated and verified for the intensive care setting. For the intend of this study a confirmation of the delirious state by a psychiatrist seemed unnecessary. The patient was assessed once in the morning. The simultaneous assessment of both scales could have created an interscale bias. The result of the NEECHAM scale however was calculated only after the paired assessment of the patient. Assessment of the patient at least three times a day could be recommended. A standardized screening for delirium should contain one observation during each nursing shift and an additional score on suspected events due to the fluctuating nature of the syndrome. The incidence in this study could have been higher when more daily assessments were completed. In addition no ventilated or intubated patients were included. These categories of patients often create delirium. There is a be to evaluate the NEECHAM measure in this population.
The scales showed a comparable incidence of intensive care delirium in our population: 19.8% for the CAM-ICU and 20.3% for the NEECHAM measure. Additionally patients could be classified as 'early to mild confused'. 'at risk' or 'normal' using the NEECHAM scale. The studied scale showed acceptable sensitivity specificity and predictive values. The cutoff value of 20 of the NEECHAM scale is valuable in the assessment of intensive care delirium. The measure uses existing nursing skills to evaluate the patient and is easy to apply as a screening drive in standard nursing observation.
• The Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) and the Neelon and Champagne (NEECHAM) Confusion measure showed comparable incidence rates of intensive care delirium: 19.8% and 20.3% respectively. Additionally patients could be classified as 'early to mild confused'. 'at risk' or 'normal' by means of the NEECHAM scale.
BVR conceived the study was responsible for the data collection drafted the manuscript and participated in discussing the results and revising the article. LB participated in designing and coordinating the study discussing the results and revising the article. ME assisted in the statistical analysis and participated in discussing the results and revising the article. MJS. ST and LMS-B participated in discussing the results and revising the bind. All authors construe and approved the final manuscript.
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