Treatment of Delirium During Critical Illness

Delirium, an acute disturbance in mental status due to another medical condition, is common and morbid in the intensive care unit. Despite its clear association with multiple common risk factors and important outcomes, including mortality and long-term cognitive impairment, both the ultimate causes of and ideal treatments for delirium remain unclear. Studies suggest that neuroinflammation, hypoxia, alterations in energy metabolism, and imbalances in multiple neurotransmitter pathways contribute to delirium, but commonly used treatments (e.g., antipsychotic medications) target only one or a few of these potential mechanisms and are not supported by evidence of efficacy. At this time, the optimal treatment for delirium during critical illness remains avoidance of risk factors, though ongoing trials may expand on the promise shown by agents such as melatonin and dexmedetomidine. Expected final online publication date for the Annual Review of Medicine, Volume 73 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Drug-induced ischemic stroke

Stroke is an acute disturbance of the blood supply to the brain, characterized by the sudden onset of focal neurological symptoms, which persists for more than 24 hours or leads to the death of the patient in a shorter period of time due to cerebrovascular pathology. In the world and in Russia, stroke remains one of the leading causes of death and disability. At the same time, ischemic stroke (IS) is more common – about 80% of cases. Many classes of drugs, such as oral contraceptives, nonsteroidal anti-inflammatory drugs, and various psychoactive substances, can contribute to the development of drug-induced IS (DI IS). Data upon the frequency of DI IS is limited. In part, this reflects the problem of identifying and confirming the causal relationship between drug prescription and the development of IS. DI IS risk factors include: abuse of caffeine and alcohol, older age, smoking, drug addiction, high doses of drugs containing provoking agents, the simultaneous use of several drugs, the presence of comorbid diseases. Adverse drug reactions develop due to the following pathophysiological mechanisms: cerebral embolism, vasoconstriction of cerebral arteries, vasculitis of the central nervous system, orthostatic hypotension. The management of a patient with a DI IS does not differ significantly from the management of a patient with IS of a different etiology and includes thrombolysis or mechanical thromboextraction (in the absence of contraindications), as well as rational methods of secondary prevention. It is necessary to completely cancel or reduce the dose of the drug, the use of which led to the development of a stroke. DI IS prevention measures include the choice of drugs with the lowest risk of its occurrence and the use of modern scales for assessing the risk of this phenomenon.

Long-term monitoring provides insight into estuarine top predator (Carcharhinus leucas) resilience following an extreme weather event

Chronic environmental change threatens biodiversity, but acute disturbance events present more rapid and immediate threats. In 2010, a cold snap across south Florida had wide-ranging impacts, including negative effects on recreational fisheries, agriculture, and ecological communities. Here, we use acoustic telemetry and historical longline monitoring to assess the long-term implications of this event on juvenile bull sharks Carcharhinus leucas in the Florida Everglades. Despite the loss of virtually all individuals (ca. 90%) within the Shark River Estuary during the cold snap, the catch per unit effort (CPUE) of age 0 sharks on longlines recovered through recruitment within 6-8 mo of the event. Acoustic telemetry revealed that habitat use patterns of age 0-2 sharks reached an equilibrium in 4-6 yr. In contrast, the CPUE and habitat use of age 3 sharks required 5-7 yr to resemble pre-cold snap patterns. Environmental conditions and predation risk returned to previous levels within 1 yr of the cold snap, but abundances of some prey species remained depressed for several years. Reduced prey availability may have altered the profitability of some microhabitats after the cold snap, leading to more rapid ontogenetic shifts to marine waters among sharks for several years. Accelerated ontogenetic shifts coupled with inter-individual behavioral variability of bull sharks likely led to a slower recovery rate than predicted based on overall shark CPUE. While intrinsic variation driven by stochasticity in dynamic ecosystems may increase the resistance of species to chronic and acute disturbance, it may also increase recovery time in filling the diversity of niches occupied prior to disturbance if resistive capacity is exceeded.

NAPICU Guidance: Introducing COVID-19 and acute disturbance

Lv:0:53:http://www.w3.org/1999/02/22-rdf-syntax-ns#XMLLiteral<xhtml:span xmlns:xhtml="http://www.w3.org/1999/xhtml" xml:lang="en">Editorial introducing new NAPICU guidance on COVID-19 and acute disturbance.</xhtml:span>

Acute drivers influence recent inshore Great Barrier Reef dynamics

Understanding the dynamics of habitat-forming organisms is fundamental to managing natural ecosystems. Most studies of coral reef dynamics have focused on clear-water systems though corals inhabit many turbid regions. Here, we illustrate the key drivers of an inshore coral reef ecosystem using 10 years of biological, environmental, and disturbance data. Tropical cyclones, crown-of-thorns starfish, and coral bleaching are recognized as the major drivers of coral loss at mid- and offshore reefs along the Great Barrier Reef (GBR). In comparison, little is known about what drives temporal trends at inshore reefs closer to major anthropogenic stress. We assessed coral cover dynamics using state-space models within six major inshore GBR catchments. An overall decline was detected in nearly half (46%) of the 15 reefs at two depths (30 sites), while the rest exhibited fluctuating (23%), static (17%), or positive (13%) trends. Inshore reefs responded similarly to their offshore counterparts, where contemporary trends were predominantly influenced by acute disturbance events. Storms emerged as the major driver affecting the inshore GBR, with the effects of other drivers such as disease, juvenile coral density, and macroalgal and turf per cent cover varying from one catchment to another. Flooding was also associated with negative trends in live coral cover in two southern catchments, but the mechanism remains unclear as it is not reflected in available metrics of water quality and may act through indirect pathways.