Matthew Duprey, BCCCP, PharmD, PhD
Investigator
Northeastern University
Providence, Rhode Island
Disclosure information not submitted.
Lisette Vernooij, PhD
Epidemiologist
Department of Intensive Care Medicine and UMC Utrecht Brain Center, University Medical Center-Utrecht, Utrecht University, Utrecht, the Netherlands, Netherlands
Disclosure information not submitted.
Sandra M.A. Dijkstra-Kersten, PhD
Epidemiologist
Department of Intensive Care Medicine and UMC Utrecht Brain Center, University Medical Center-Utrecht, Utrecht University, Utrecht, the Netherlands, Netherlands
Disclosure information not submitted.
Irene Zaal, MD, PhD
Intensivist
Department of Intensive Care Medicine and UMC Utrecht Brain Center, University Medical Center-Utrecht, Utrecht University, Utrecht, the Netherlands, Netherlands
Disclosure information not submitted.
Céline Gélinas, PhD, RN
Professor and Senior Researcher
3Ingram School of Nursing, McGill University, and Centre for Nursing Research, Jewish General Hospital – CIUSSS West-Central Montréal, Montréal, QC, Canada, Quebec, Canada
Disclosure information not submitted.
John Devlin, BCCCP, PharmD, MCCM
Professor
Northeastern University
Boston, Massachusetts, United States
Disclosure information not submitted.
Arjen J.C. Slooter, MD, PhD
Neurointensivist and Full Professor
Department of Intensive Care Medicine and UMC Utrecht Brain Center, University Medical Center-Utrecht, Utrecht University, Utrecht, the Netherlands, Netherlands
Disclosure information not submitted.
Title: The Complex Interplay between Pain and Delirium in Critically Ill Adults
Introduction: Interactions between pain and delirium are complex and dependent on opioids, which increase delirium risk. Cohort studies in non-critically ill adults have found pain to increase delirium. We undertook an exploratory analysis to evaluate the association between pain and delirium in critically ill adults.
Methods: Consecutive critically ill adults admitted ≥24 hours to a 32-bed mixed ICU were enrolled between 01/2011 and 03/2019. Daily mental status was classified as awake without delirium, delirium or coma. Pain was assessed by nurses 6x daily using a 0-10cm Visual Analog Scale (VAS) or the Critical Care Pain Observation Tool (CPOT). Maximal daily pain was divided into mutually exclusive categories: no clinically significant detected pain (VAS 0-4,CPOT 0-2), moderate pain (VAS 5-6,CPOT 3-4), and severe pain (VAS 7-10,CPOT 5-8). The association between the maximal pain category on day t and mental status on day t+1 was assessed using multinomial logistic regression in a first-order Markov model controlling for opioid administration.
Results: The 4075 patients (age 60.9±15.4, 63.6% male, 62.2% surgical, APACHE-IV 58.5±28.0) contributed 26,250 ICU days. 1430 patients were delirious during 6176 ICU days. Moderate and severe pain was detected on 1759 (11.8%) and 1157 (7.7%) days without delirium and on 735 (11.9%) and 436 (7.1%) days with delirium (p=0.1), respectively. Moderate or severe pain (vs no clinically significant detectable pain) was found to be inversely associated with a transition from awake without delirium to delirium (OR 0.71; 95% CI 0.60-0.85). Results were similar when days with only severe pain (OR 0.72; 95% CI 0.53-0.97) or only moderate pain (OR 0.71; 95% CI 0.61-0.88) were considered. The results were stable when controlling for opioid dose (severe pain OR 0.70; 95%CI 0.52-0.94 and moderate pain OR 0.74; 95%CI 0.61-0.89). Modeling pain as a three-level variable, and controlling for opioid use, found the same inverse association with delirium for both severe pain (OR 0.72; 95%CI 0.54-0.97) and moderate pain (OR 0.75; 95%CI 0.62-0.91).
Conclusions: Realizing the challenges of pain assessment in patients with delirium, pain seems not to be a strong risk factor for delirium in critically ill adults. Future research is necessary to better understand this complex relationship.