Delirium

Journal Article Annotations
2020, 4th Quarter

Delirium

Annotations by Maalobeeka Gangopadhyay, MD
December, 2020

  1. Association of Plasma Neurofilament Light with Postoperative Delirium.
  2. Platelet-to-lymphocyte ratio as a predictive index for delirium in critically ill patients: A retrospective observational study.
  3. The effect of dexmedetomidine on postoperative behaviour change in children: a randomised controlled trial

    PUBLICATION #1 — Delirium

    Association of Plasma Neurofilament Light with Postoperative Delirium
    Tamara G Fong, Sarinnapha M Vasunilashorn, Long Ngo, Towia A Libermann, Simon T Dillon, Eva M Schmitt, Alvaro Pascual-Leone, Steven E Arnold, Richard N Jones, Edward R Marcantonio, Sharon K Inouye, SAGES Study Group

    Annotation

    The finding:
    Patients with the highest quartile measurements of neurofilament light chain (NfL) preoperatively and on postoperative day 2 had the highest risk for developing postoperative delirium and experienced increased delirium severity and duration. Also, those patients with elevations of NfL one month postoperatively were more likely to have general cognitive performance impairments.

    Strength and weaknesses:
    This was a nested case-control study within the larger SAGES study which collects a biobank of plasma at multiple time points. The patients have detailed longitudinal followup; patients with clinically evident dementia were excluded; controls were matched carefully to reduce confounding variables. Matching resulted in a small sample which was homogenous in ethnicity and educational attainment; these were patients undergoing elective surgery so were likely relatively healthy. 

    Relevance:
    The NfL biomarker may help stratify delirium risk preoperatively and help optimize management before, during and after surgery. In addition, this level postoperatively can be used to trigger proactive treatments for those who are at risk of cognitive decline.

    Type of study (EBM guide):
    Case-control observational study


    PUBLICATION #2 — Delirium

    Platelet-to-lymphocyte ratio as a predictive index for delirium in critically ill patients: A retrospective observational study
    Xuandong Jiang, Yanfei Shen, Qiang Fang, Weimin Zhang, Xuping Cheng

    Annotation

    The finding:
    The charts of 319 ICU patients were examined, of which 29 had delirium; a higher platelet to lymphocyte ratio (PLR) (>100) was associated with a higher incidence of delirium. Hospital and ICU length of stay were examined and not significantly different between delirium and non-delirium cohorts while the duration of mechanical ventilation was longer in the delirium cohort.

    Strength and weaknesses:
    The study population was heterogenous and included both medical and postsurgical patients; the results can be more widely generalized. In addition to PLR, there were many other factors predicting delirium: age, APACHE II scores, history of respiratory diseases, history of surgery, serum glucose level, albumin level, platelet count, and PaO2/FiO2. This is a pilot study and the incidence of delirium was lower compared to other studies.

    Relevance:
    The PLR is an inexpensive, simple-to-calculate marker that may help to predict delirium in ICU patients.

    Type of study (EBM guide):
    case-control observational study


    PUBLICATION #3 — Delirium

    The effect of dexmedetomidine on postoperative behaviour change in children: a randomised controlled trial.
    P F Lee-ArcherB S von Ungern-SternbergM ReadeM BettsD HaenkeA KeysT RanceK GibbonsD Long

    Annotation

    The finding:
    Children 2-7 years old undergoing elective day surgery were randomized to control, premedication with intranasal dexmedetomidine, or intraoperative intravenous dexemedetomidine conditions. Incidence of behavioral changes postoperative day 3 was similar in all 3 groups; at postoperative day 28, the dexmedetomidine intra-operative group exhibited significantly less negative behavior change compared to the control and pre-medication groups. Emergence delirium occurred in 7 patients: 5 in the control group and 1 in each of the treatment groups. Those exposed to demedetomidine had longer length of stay in recovery (11 min) and in the hospital (33 min) but less report of pain compared to control group.

    Strength and weaknesses:
    Strengths of the study included use of a validated tool for delirium screening in the recovery setting and the utilization of scales for behavior change (the Post-Hospitalization Behavior Questionnaire and the Strength and Difficulties Questionnaire). The investigators ran an appropriately powered, double blind, randomized controlled trial. Limitations are that the study was conducted at a single center; the nurses utilizing the CAPD were not familiar with the tool; and these are relatively healthy children in a day procedure so generalizability may be limited to sicker populations.

    Relevance:
    For same day procedures in healthy children, use of dexmedetomidine may lead to fewer negative behaviors, less frequent emergence delirium, and improved pain control.

    Type of study (EBM guide):
    randomized control trial