Guanfacine for Hyperactive Delirium: A Case Series

Dyspnea and Dyspnea-Associated Anxiety in the ICU Patient Population: A Narrative Review for CL Psychiatrists

BACKGROUND

Consultation-liaison psychiatrists frequently address dyspnea in intensive care unit (ICU) patients. Dyspnea is common in this patient population, but is frequently misunderstood and underappreciated in noncommunicative ICU patients.

OBJECTIVE

This paper provides an updated review on dyspnea specifically in the ICU population, including its pathophysiology and management, pharmacological and nonpharmacological, aimed at consultation-liaison psychiatrists consulting in ICU.

METHODS

A literature review was conducted with PubMed, querying published articles for topics associated with dyspnea and dyspnea-associated anxiety in ICU patient populations. When literature in ICU populations was limited, information was deduced from dyspnea and anxiety management from non-ICU populations. Articles discussing the definition of dyspnea, mechanistic pathways, screening tools, and pharmacologic and nonpharmacologic management were included.

RESULTS

A reference guide was created to help consultation-liaison psychiatrists and intensivists in the screening and treatment of dyspnea and dyspnea-associated anxiety in critically ill patients.

CONCLUSIONS

Dyspnea is frequently associated with anxiety, prolonged days on mechanical ventilation, and worse quality of life after discharge. It can also increase the risk of posttraumatic stress disorder post-ICU discharge. However, it is not routinely screened for, identified, or addressed in the ICU. This manuscript provides an updated review on dyspnea and dyspnea-associated anxietyin the ICU population, including its pathophysiology and management, and offers a useful reference for consultation-liaison psychiatrists to provide treatment recommendations.

Scientific rationale for the use of α2A-adrenoceptor agonists in treating neuroinflammatory cognitive disorders

Neuroinflammatory disorders preferentially impair the higher cognitive and executive functions of the prefrontal cortex (PFC). This includes such challenging disorders as delirium, perioperative neurocognitive disorder, and the sustained cognitive deficits from "long-COVID" or traumatic brain injury. There are no FDA-approved treatments for these symptoms; thus, understanding their etiology is important for generating therapeutic strategies. The current review describes the molecular rationale for why PFC circuits are especially vulnerable to inflammation, and how α2A-adrenoceptor (α2A-AR) actions throughout the nervous and immune systems can benefit the circuits in PFC needed for higher cognition. The layer III circuits in the dorsolateral PFC (dlPFC) that generate and sustain the mental representations needed for higher cognition have unusual neurotransmission and neuromodulation. They are wholly dependent on NMDAR neurotransmission, with little AMPAR contribution, and thus are especially vulnerable to kynurenic acid inflammatory signaling which blocks NMDAR. Layer III dlPFC spines also have unusual neuromodulation, with cAMP magnification of calcium signaling in spines, which opens nearby potassium channels to rapidly weaken connectivity and reduce neuronal firing. This process must be tightly regulated, e.g. by mGluR3 or α2A-AR on spines, to prevent loss of firing. However, the production of GCPII inflammatory signaling reduces mGluR3 actions and markedly diminishes dlPFC network firing. Both basic and clinical studies show that α2A-AR agonists such as guanfacine can restore dlPFC network firing and cognitive function, through direct actions in the dlPFC, but also by reducing the activity of stress-related circuits, e.g. in the locus coeruleus and amygdala, and by having anti-inflammatory actions in the immune system. This information is particularly timely, as guanfacine is currently the focus of large clinical trials for the treatment of delirium, and in open label studies for the treatment of cognitive deficits from long-COVID.

Preventing and treating delirium in clinical settings for older adults

Delirium is a serious consequence of many acute or worsening chronic medical conditions, a side effect of medications, and a precipitant of worsening functional and cognitive status in older adults. It is a syndrome characterized by fluctuations in cognition and impaired attention that develops over a short period of time in response to an underlying medical condition, a substance (prescribed, over the counter, or recreational), or substance withdrawal and can be multi-factorial. We present a narrative review of the literature on nonpharmacologic and pharmacologic approaches to prevention and treatment of delirium with a focus on older adults as a vulnerable population. Older adult patients are most at risk due to decreasing physiologic reserves, with delirium rates of up to 80% in critical care settings. Presentation of delirium can be hyperactive, hypoactive, or mixed, making identification and study challenging as patients with hypoactive delirium are less likely to come to attention in an inpatient or long-term care setting. Studies of delirium focus on prevention and treatment with nonpharmacological or medication interventions, with the preponderance of evidence favoring multi-component nonpharmacological approaches to prevention as the most effective. Though use of antipsychotic medication in delirium is common, existing evidence does not support routine use, showing no clear benefit in clinically significant outcome measures and with evidence of harm in some studies. We therefore suggest that antipsychotics be used to treat agitation, psychosis, and distress associated with delirium at the lowest effective doses and shortest possible duration and not be considered a treatment of delirium itself. Future studies may clarify the use of other agents, such as melatonin and melatonin receptor agonists, alpha-2 receptor agonists, and anti-epileptics.

A Retrospective Analysis of Guanfacine for the Pharmacological Management of Delirium

Background Delirium is a syndrome of acute brain failure that represents a change from an individual's baseline cognitive functioning characterized by deficits in attention and multiple aspects of cognition that fluctuate in severity over time. The symptomatic management of delirium's behavioral manifestations remains difficult. The alpha-2 agonists, dexmedetomidine and clonidine, are efficacious, but their potential cardiovascular adverse effects limit their utilization. Guanfacine is an oral alpha-2 agonist with a lower potential for such adverse outcomes; however, its use in delirium has not been studied. Methods A retrospective descriptive analysis of guanfacine for managing hyperactive or mixed delirium at Tampa General Hospital from January 2020 to October 2020 was conducted. The primary outcome was the time reduction in acute sedative administration. Secondary outcomes included renewed participation in physical therapy or occupational therapy (PT/OT), decreased opioid use, and an incidence of cardiovascular adverse effects. Results One hundred forty-nine patients were identified as having received guanfacine for managing delirium during the study period. All experienced a reduction in acute sedative use after the initiation of guanfacine. In 93 patients receiving PT/OT and no longer participating due to behavioral agitation, 74% had a documented renewal of services within four days. Of 112 patients on opioids, 70% experienced a 25% reduction in opioid administration within four days. No patients experienced consecutive episodes of hypotension that required a change in their clinical care. Two patients experienced a single episode of consecutive bradycardia that led to the discontinuation of guanfacine.  Conclusions Based on our retrospective study, guanfacine is a well-tolerated medication for the management of delirium. Even in medically and critically ill patients, cardiovascular adverse events were rare with guanfacine. Patients treated with guanfacine experienced decreased acute sedative use for behavioral agitation. Additionally, patients treated with guanfacine received fewer opioids and were better able to participate in PT/OT. Future studies with prospective, randomized, placebo-controlled designs are warranted to evaluate this promising intervention for delirium further.

Guanfacine for irritability, impulsivity, and agitation in elderly patients: A report of two cases

Background

Irritability, impulsivity, and agitation in elderly patients with dementia are highly prevalent and extremely burdening for patients, caregivers, and medical staff. In general hospitals, they have been one of the major problems that develop and disturb care and treatment. However, the mechanisms underlying these symptoms remain unclear, and there is no established treatment. In actual clinical practice, antipsychotic drugs and mood stabilizers have been mainly used as pharmacotherapies for these symptoms, but adverse effects of these drugs have often been problematic.

Case Presentation

We report two valuable cases of elderly patients who were admitted to our hospital due to physical disorders and developed irritability, impulsivity, and agitation, which were effectively treated with guanfacine at very low doses and in a short period.

Conclusion

The present cases suggest that guanfacine may be a therapeutic option for treating irritability, impulsivity, and agitation in elderly patients.

Neuromodulation of prefrontal cortex cognitive function in primates: the powerful roles of monoamines and acetylcholine

The primate prefrontal cortex (PFC) subserves our highest order cognitive operations, and yet is tremendously dependent on a precise neurochemical environment for proper functioning. Depletion of noradrenaline and dopamine, or of acetylcholine from the dorsolateral PFC (dlPFC), is as devastating as removing the cortex itself, and serotonergic influences are also critical to proper functioning of the orbital and medial PFC. Most neuromodulators have a narrow inverted U dose response, which coordinates arousal state with cognitive state, and contributes to cognitive deficits with fatigue or uncontrollable stress. Studies in monkeys have revealed the molecular signaling mechanisms that govern the generation and modulation of mental representations by the dlPFC, allowing dynamic regulation of network strength, a process that requires tight regulation to prevent toxic actions, e.g., as occurs with advanced age. Brain imaging studies in humans have observed drug and genotype influences on a range of cognitive tasks and on PFC circuit functional connectivity, e.g., showing that catecholamines stabilize representations in a baseline-dependent manner. Research in monkeys has already led to new treatments for cognitive disorders in humans, encouraging future research in this important field.