Mark van den Boogaard1, Annelies Wassenaar2, Frank M P van Haren3, Arjen J C Slooter4, Philippe G Jorens5, Mathieu van der Jagt6, Koen S Simons7, Ingrid Egerod8, Lisa D Burry9, Albertus Beishuizen10, Peter Pickkers11, John W Devlin12. 1. Department of Intensive Care Medicine, Radboud University Medical Center, Nijmegen, the Netherlands; Radboud Institute for Health Sciences, Radboud University Medical Center, the Netherlands. Electronic address: Mark.vandenBoogaard@Radboudumc.nl. 2. Department of Intensive Care Medicine, Radboud University Medical Center, Nijmegen, the Netherlands; Radboud Institute for Health Sciences, Radboud University Medical Center, the Netherlands. Electronic address: Annelies.Wassenaar@radboudumc.nl. 3. Intensive Care Unit, The Canberra Hospital, Woden, Canberra, Australia; Australian National University Medical School, Canberra, Australia; University of Canberra, Faculty of Health, Canberra, Australia. Electronic address: frank.vanharen@act.gov.au. 4. Department of Intensive Care Medicine and Brain Center Rudolf Magnus, University Medical Centre Utrecht, Utrecht, the Netherlands. Electronic address: A.Slooter-3@umcutrecht.nl. 5. Department of Critical Care Medicine, Antwerp University Hospital, University of Antwerp, Edegem, Antwerp, Belgium. Electronic address: Philippe.Jorens@uza.be. 6. Department of Intensive Care Adults, Erasmus Medical Center, Rotterdam, the Netherlands. Electronic address: m.vanderjagt@erasmusmc.nl. 7. Department of Intensive Care Medicine, Jeroen Bosch Ziekenhuis, 's-Hertogenbosch, the Netherlands. Electronic address: K.Simons@jbz.nl. 8. Intensive Care Unit, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark. Electronic address: ingrid.egerod@regionh.dk. 9. Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Canada; Mount Sinai Hospital, Sinai Health System, Toronto, Canada. Electronic address: lisa.burry@sinaihealthsystem.ca. 10. Department of Intensive Care, Medisch Spectrum Twente, Enschede, the Netherlands. Electronic address: B.Beishuizen@mst.nl. 11. Department of Intensive Care Medicine, Radboud University Medical Center, Nijmegen, the Netherlands; Radboud Center for Infectious Diseases, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands. Electronic address: Peter.Pickkers@radboudumc.nl. 12. School of Pharmacy, Northeastern University, Boston, USA; Division of Pulmonary, Critical Care and Sleep Medicine, Tufts Medical Center, Boston, USA. Electronic address: jdevlin@northeastern.edu.
Abstract
BACKGROUND: Guidelines advocate intensive care unit (ICU) patients be regularly assessed for delirium using either the Confusion Assessment Method for the ICU (CAM-ICU) or the Intensive Care Delirium Screening Checklist (ICDSC). Single-centre studies, primarily with the CAM-ICU, suggest level of sedation may influence delirium screening results. OBJECTIVE: The objective of this study was to determine the association between level of sedation and delirium occurrence in critically ill patients assessed with either the CAM-ICU or the ICDSC. METHODS: This was a secondary analysis of a multinational, prospective cohort study performed in nine ICUs from seven countries. Consecutive ICU patients with a Richmond Agitation-Sedation Scale (RASS) of -3 to 0 at the time of delirium assessment where a RASS ≤ 0 was secondary to a sedating medication. Patients were assessed with either the CAM-ICU or the ICDSC. Logistic regression analysis was used to account for factors with the potential to influence level of sedation or delirium occurrence. RESULTS: Among 1660 patients, 1203 patients underwent 5741 CAM-ICU assessments [9.6% were delirium positive; at RASS = 0 (3.3% were delirium positive), RASS = -1 (19.3%), RASS = -2 (35.1%); RASS = -3 (39.0%)]. The other 457 patients underwent 3210 ICDSC assessments [11.6% delirium positive; at RASS = 0 (4.9% were delirium positive), RASS = -1 (15.8%), RASS = -2 (26.6%); RASS = -3 (20.6%)]. A RASS of -3 was associated with more positive delirium evaluations (odds ratio: 2.31; 95% confidence interval: 1.34-3.98) in the CAM-ICU-assessed patients (vs. the ICDSC-assessed patients). At a RASS of 0, assessment with the CAM-ICU (vs. the ICDSC) was associated with fewer positive delirium evaluations (odds ratio: 0.58; 95% confidence interval: 0.43-0.78). At a RASS of -1 or -2, no association was found between the delirium assessment method used (i.e., CAM-ICU or ICDSC) and a positive delirium evaluation. CONCLUSIONS: The influence of level of sedation on a delirium assessment result depends on whether the CAM-ICU or ICDSC is used. Bedside ICU nurses should consider these results when evaluating their sedated patients for delirium. Future research is necessary to compare the CAM-ICU and the ICDSC simultaneously in sedated and nonsedated ICU patients. TRIAL REGISTRATION: ClinicalTrials.gov; NCT02518646.
BACKGROUND: Guidelines advocate intensive care unit (ICU) patients be regularly assessed for delirium using either the Confusion Assessment Method for the ICU (CAM-ICU) or the Intensive Care Delirium Screening Checklist (ICDSC). Single-centre studies, primarily with the CAM-ICU, suggest level of sedation may influence delirium screening results. OBJECTIVE: The objective of this study was to determine the association between level of sedation and delirium occurrence in critically ill patients assessed with either the CAM-ICU or the ICDSC. METHODS: This was a secondary analysis of a multinational, prospective cohort study performed in nine ICUs from seven countries. Consecutive ICU patients with a Richmond Agitation-Sedation Scale (RASS) of -3 to 0 at the time of delirium assessment where a RASS ≤ 0 was secondary to a sedating medication. Patients were assessed with either the CAM-ICU or the ICDSC. Logistic regression analysis was used to account for factors with the potential to influence level of sedation or delirium occurrence. RESULTS: Among 1660 patients, 1203 patients underwent 5741 CAM-ICU assessments [9.6% were delirium positive; at RASS = 0 (3.3% were delirium positive), RASS = -1 (19.3%), RASS = -2 (35.1%); RASS = -3 (39.0%)]. The other 457 patients underwent 3210 ICDSC assessments [11.6% delirium positive; at RASS = 0 (4.9% were delirium positive), RASS = -1 (15.8%), RASS = -2 (26.6%); RASS = -3 (20.6%)]. A RASS of -3 was associated with more positive delirium evaluations (odds ratio: 2.31; 95% confidence interval: 1.34-3.98) in the CAM-ICU-assessed patients (vs. the ICDSC-assessed patients). At a RASS of 0, assessment with the CAM-ICU (vs. the ICDSC) was associated with fewer positive delirium evaluations (odds ratio: 0.58; 95% confidence interval: 0.43-0.78). At a RASS of -1 or -2, no association was found between the delirium assessment method used (i.e., CAM-ICU or ICDSC) and a positive delirium evaluation. CONCLUSIONS: The influence of level of sedation on a delirium assessment result depends on whether the CAM-ICU or ICDSC is used. Bedside ICU nurses should consider these results when evaluating their sedated patients for delirium. Future research is necessary to compare the CAM-ICU and the ICDSC simultaneously in sedated and nonsedated ICU patients. TRIAL REGISTRATION: ClinicalTrials.gov; NCT02518646.