Altered cortical brain activity in end stage liver disease assessed by multi-channel near-infrared spectroscopy: Associations with delirium

Functional near-infrared spectroscopy guided mapping of frontal cortex, a novel modality for assessing emergence delirium in children: A prospective observational study

INTRODUCTION

Despite an 18%-30% prevalence, there is no consensus regarding pathogenesis of emergence delirium after anesthesia in children. Functional near-infrared spectroscopy (fNIRS) is an optical neuroimaging modality that relies on blood oxygen level-dependent response, translating to a mean increase in oxyhemoglobin and a decrease in deoxyhemoglobin. We aimed to correlate the emergence delirium in the postoperative period with the changes in the frontal cortex utilizing fNIRS reading primarily and also with blood glucose, serum electrolytes, and preoperative anxiety scores.

METHODS

A total of 145 ASA I and II children aged 2-5 years, undergoing ocular examination under anesthesia, were recruited by recording the modified Yale Preoperative Anxiety Score after acquiring the Institute Ethics Committee approval and written informed parental consent. Induction and maintenance were done with O2, N2O, and Sevoflurane. The emergence delirium was assessed using the PAED score in the postoperative period. The frontal cortex fNIRS recordings were taken throughout anesthesia.

RESULTS

A total of 59 children (40.7%) had emergence delirium. The ED+ group had a significant activation left superior frontal cortex (t = 2.26E+00; p = .02) and right middle frontal cortex (t = 2.27E+00; p = .02) during induction, significant depression in the left middle frontal (t = -2.22E+00; p = .02), left superior frontal and bilateral medial (t = -3.01E+00; p = .003), right superior frontal and bilateral medial (t = -2.44E+00; p = .015), bilateral medial and superior (t = -3.03E+00; p = .003), and right middle frontal cortex (t = -2.90E+00; p = .004) during the combined phase of maintenance, and significant activation in cortical activity in the left superior frontal cortex (t = 2.01E+00; p = .0047) during the emergence in comparison with the ED- group.

CONCLUSION

There is significant difference in the change in oxyhemoglobin concentration during induction, maintenance, and emergence in specific frontal brain regions between children with and without emergence delirium.

Delirium Among Adults Undergoing Solid Organ Transplantation

Purpose of Review

To summarize the research on post-operative delirium among patients undergoing solid organ transplantation in efforts to improve recognition, evaluation, and management, as well as highlight areas for future research.

Recent Findings

Delirium is a common complication in patients with organ failure before and after undergoing solid organ transplant (range: 4.7-47%). However, it is frequently unrecognized and underdiagnosed-even among those closely monitored after major surgery-given that its manifestation is often variable and inconsistent. Delirium has multifactorial etiologies comprising of a complex mix of predisposing recipient, donor, and transplant factors, as well as intraoperative and perioperative factors. Evidence suggests that delirium risk increases with presence of a greater number of such risk factors, and can lead to adverse outcomes such as increased hospital length of stay, time in the ICU, time on mechanical ventilators, graft dysfunction, graft loss, and mortality. Though no trials have been conducted among transplant populations specifically, delirium has been shown to be preventable among hospitalized older adults generally. Multicomponent, primary prevention strategies designed to target multiple risk factors of delirium, such as cognitive impairment, sleep deprivation, immobility, visual impairment, hearing impairment, and dehydration, have been identified as most effective. Whether these approaches translate to improvements in quality of life and long-term health outcomes among patients with organ failure before and after transplantation is yet to be determined.

Summary

Delirium is an important, common, yet potentially preventable complication among patients with organ failure. Future studies are needed to test the efficacy of multicomponent, primary prevention strategies on long-term health outcomes among these vulnerable populations.

Development and feasibility of a smartphone-based test for the objective detection and monitoring of attention impairments in delirium in the ICU

PURPOSE

Delirium in the ICU is under-diagnosed. We evaluated feasibility and performance of a novel smartphone-based test for objectively detecting inattention in delirium.

MATERIAL AND METHODS

DelApp-ICU combines a behavioural assessment and an attention task, whereby participants follow simple commands and count serially presented circles (score range 0-12, lower scores indicating worse performance). We assessed feasibility through staff interviews. Then we performed a preliminary case-control study in patients with and without delirium (ascertained with the Confusion Assessment Method for the ICU) who underwent the DelApp-ICU on up to 4 days.

RESULTS

Forty-six patients (median age = 57.5 years, range 18-83) were assessed 89 times in total (N's = 46, 29, 10 and 4 for subsequent assessments; 33.7% delirious). DelApp-ICU scores were lower in delirium (N = 20; median = 0.5, Inter-Quartile Range (IQR) = 0-4.75) compared to no delirium (N = 26, median = 12, IQR = 8-12) on days 1, 2 and 3 (p < 0.001, p < 0.001 and p < 0.05, respectively). A DelApp-ICU score ≤6 was 100% sensitive and 96% specific to delirium on day 1. Positive and Negative Predictive Values were 91% and 100%, respectively. DelApp-ICU scores were responsive to changes in CAM-ICU status.

CONCLUSIONS

DelApp-ICU shows promise for assessing inattention and delirium in ICU patients, including longitudinally monitoring deficits and providing a metric of delirium severity.