Treating agitation with dexmedetomidine in the ICU

General Anesthesia Activates a Central Anxiolytic Center in the BNST

Low doses of general anesthetics like ketamine and dexmedetomidine have anxiolytic properties independent of their sedative effects. How these different drugs exert these anxiolytic effects is not well understood. We discovered a population of GABAergic neurons in the oval division of the bed nucleus of the stria terminalis that is activated by multiple anesthetics and the anxiolytic drug diazepam (ovBNST GA ). A majority of ovBNST GA neurons express neurotensin receptor 1 (Ntsr1) and innervate brain regions known to regulate anxiety and stress responses. Optogenetic activation ovBNST GA or ovBNST Ntsr1 neurons significantly attenuated anxiety-like behaviors in both naïve animals and mice with inflammatory pain, while inhibition of these cells increased anxiety. Notably, activation of these neurons decreased heart rate and increased heart rate variability, suggesting that they reduce anxiety through modulation of the autonomic nervous system. Our study identifies ovBNST GA /ovBNST Ntsr1 neurons as one of the brain's endogenous anxiolytic centers and a potential therapeutic target for treating anxiety-related disorders.

HIGHLIGHTS

General anesthetics and anxiolytics activate a population of neurons in the ovBNSTAnesthesia-activated ovBNST neurons bidirectionally modulate anxiety-like behaviorMost anesthesia-activated ovBNST neurons express neurotensin receptor 1 ovBNST Ntsr1 neuron activation shifts autonomic responses to an anxiolytic state.

Improving Outcomes for Hospitalized Patients Pre- and Post-COVID-19

Purpose

Barriers to effective patient–provider communication increase the risk that a patient will experience a hospital-acquired condition (HAC) that will negatively impact the patient's health outcomes. Providing patients with communication tools can significantly reduce the risks of experiencing HACs. This article describes how barriers to effective patient–provider communication can impact patient outcomes and reports on the incidence of HACs in patients who received assistive technology to address barriers to patient–provider communication. This topic is of critical relevance, as the COVID-19 pandemic has dramatically increased the number of patients who face communication barriers and the accompanying challenges encountered by their health care providers.

Method/Approach

The researchers compared the number of expected HACs based on previously obtained data to the number of HACs reported among patients who received an assistive technology intervention. Additionally, the impact of COVID-19 on patient–provider communication was discussed through the provision of case descriptions from frontline speech-language pathologists who have worked in COVID-19 intensive care units.

Results

The patients who received the assistive technology intervention had a significantly lower incidence of HACs than what would be expected in hospital settings. Clinicians working directly with patients with COVID-19 identified suggestions on how both patients and providers can address the barriers to effective patient–provider communication.

Conclusion

A key to better patient outcomes and lower health care costs will require making the provision of communication tools part of the standard of care for all patients facing barriers to communication.

Role of α2-agonists in the treatment of acute alcohol withdrawal

OBJECTIVE

To evaluate literature reporting on the role of norepinephrine in alcohol withdrawal and to determine the safety and efficacy of α(2)-agonists in reducing symptoms of this severe condition.

DATA SOURCES

Articles evaluating the efficacy and safety of the α(2)-agonists clonidine and dexmedetomidine were identified from an English-language MEDLINE search (1966-December 2010). Key words included alcohol withdrawal, delirium tremens, clonidine, dexmedetomidine, α(2)-agonist, norepinephrine, and sympathetic overdrive.

STUDY SELECTION AND DATA EXTRACTION

Studies that focused on the safety and efficacy of clonidine and dexmedetomidine in both animals and humans were selected.

DATA SYNTHESIS

The noradrenergic system, specifically sympathetic overdrive during alcohol withdrawal, may play an important role in withdrawal symptom development. Symptoms of sympathetic overdrive include anxiety, agitation, elevated blood pressure, tachycardia, and tremor. Therefore, α(2)-agonists, which decrease norepinephine release, may have a role in reducing alcohol withdrawal symptoms. The majority of controlled animal and human studies evaluated clonidine, but the most recent literature is from case reports on dexmedetomidine. The literature reviewed here demonstrate that these 2 α(2)-agonists safely and effectively reduce symptoms of sympathetic overdrive and concomitant medication use. Dexmedetomidine may offer an advantage over current sedative medications used in the intensive care unit, such as not requiring intubation with its use, and therefore further study is needed to fully elicit its benefit in alcohol withdrawal.

CONCLUSION

Clonidine and dexmedetomidine may provide additional benefit in managing alcohol withdrawal by offering a different mechanism of action for targeting withdrawal symptoms. Based on literature reviewed here, the primary role for clonidine and dexmedetomidine is as adjunctive treatment to benzodiazepines, the standard of care in alcohol withdrawal.

Review Article: Dexmedetomidine: Does it Have Potential in Palliative Medicine?

Dexmedetomidine, is a α 2 adrenergic agonist approved by the Food and Drug administration for sedation and analgesia. A highly potent α2 adrenergic agonist, it has quick onset of action, with peak effects within 1 hour of administration. It is metabolized in the liver and eliminated in the urine as a glucuronide. Dexmedetomidine is a substrate and inhibitor of cytochrome oxidase 2D6, but clinical evidence of significant drug interactions is lacking. Clinical trials suggest efficacy for the treatment of delirium in the intensive care unit setting with efficacy comparable to haloperidol and benzodiazepines. Dexmedetomidine also has an opioid-sparing action and can act to enhance analgesia. The purpose of this article is to review the pharmacodynamics and pharmacology of dexmedetomidine, and examine its potential use in the palliative care population, especially with regard to the management of delirium.

Fever and agitation in elderly ICU patients: a descriptive study

OBJECTIVE

To investigate the association between fever and agitation in elderly, critically ill patients.

SETTING

Medical-surgical Intensive Care Unit (ICU) of a Greek, tertiary care hospital.

RESEARCH METHODOLOGY

Descriptive, quantitative study conducted from October 2005 to September 2006. Patient temperature was measured by a tympanic membrane or an axillary thermometer. Agitation-Sedation scale was used for evaluating agitation. Variables found to contribute to agitation in previous studies were also collected.

RESULTS

One hundred sixty-one patients > or =65 years, who were consecutively admitted to the ICU, were enrolled. Fever was found to be an independent predictor of agitation (OR, 1.86; 95% CI, 1.02-3.49). High fever (>39.3 degrees C), was associated with a higher possibility for patients to manifest severe agitation (p=0.046).

CONCLUSION

Considering the significant adverse consequences of agitation, antipyretic therapy may be recommended for the elderly ICU population, especially when fever is combined with other factors predisposing to agitation or when fever becomes high.