Alcohol,drug misuse and suicide attempts: unrecognised causes of out of hospital cardiac arrests admitted to intensive care units

Aim  To assess the contribution of alcohol, drug abuse and suicide attempts to out of hospital cardiac arrests (OHCA) who are admitted to our intensive care unit (ICU). Methods  Retrospective review of all OHCA admitted to the ICU over a 2-year period. Results  There were 26 OHCA. Six patients survived, all of whom had a cardiac aetiology for their arrest. Ten patients arrested due to external factors (drug misuse n = 4, alcohol excess n = 1, suicide attempts n = 4 and accidental choking n = 1). All of the patients who arrested secondary to external factors were young (37.2 ± 13.58 years), 90% were male and all died in hospital. All of the cases of drug misuse involved cocaine. Conclusion  Alcohol, drug misuse and suicide attempts contribute significantly to the number of OHCA which are admitted to ICU. Moreover, cocaine usage has contributed to a number of OHCA in our study.     

Short report: permethrin and DDT resistance in the malaria vector Anopheles arabiensis from eastern Sudan

Assessment of resistance to DDT and permethrin insecticides and molecular detection of knockdown resistance (kdr) alleles were conducted in three populations of Anopheles arabiensis from eastern Sudan. Bioassay mortalities ranged from 96.9% to 99.6% for 4% DDT and from 98.4% to 100% for 1% permethrin. The L1014F and L1014S alleles were detected in 25 of 498 mosquitoes. The overall kdr frequencies ranged from 7.0% in the area where insecticide-treated nets were used to 3.0% in the area with agricultural insecticide use. The presence of the kdr alleles in An. arabiensis in Sudan emphasizes the need to develop appropriate resistance monitoring and management strategies for An. arabiensis.     

Amphibian and reptile declines over 35 years at La Selva, Costa Rica

Amphibians stand at the forefront of a global biodiversity crisis. More than one-third of amphibian species are globally threatened, and over 120 species have likely suffered global extinction since 1980. Most alarmingly, many rapid declines and extinctions are occurring in pristine sites lacking obvious adverse effects of human activities. The causes of these "enigmatic" declines remain highly contested. Still, lack of long-term data on amphibian populations severely limits our understanding of the distribution of amphibian declines, and therefore the ultimate causes of these declines. Here, we identify a systematic community-wide decline in populations of terrestrial amphibians at La Selva Biological Station, a protected old-growth lowland rainforest in lower Central America. We use data collected over 35 years to show that population density of all species of terrestrial amphibians has declined by approximately 75% since 1970, and we show identical trends for all species of common reptiles. The trends we identify are neither consistent with recent emergence of chytridiomycosis nor the climate-linked epidemic hypothesis, two leading putative causes of enigmatic amphibian declines. Instead, our data suggest that declines are due to climate-driven reductions in the quantity of standing leaf litter, a critical microhabitat for amphibians and reptiles in this assemblage. Our results raise further concerns about the global persistence of amphibian populations by identifying widespread declines in species and habitats that are not currently recognized as susceptible to such risks.     

Reversibility of delirium in terminally ill patients and predictors of mortality

In this study, factors related to reversibility and mortality in consecutive cases of Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) delirium [n = 121] occurring in palliative care patients were evaluated. Delirium was assessed with the revised Delirium Rating Scale (DRS-R98) and Cognitive Test for Delirium (CTD). Patients were followed until recovery from delirium or death. In all, 33 patients (27%) recovered from delirium before death. Mean time until death was 39.7 +/- 69.8 days in patients with reversible delirium [n = 33] versus 16.8 +/- 10.0 days in those with irreversible delirium [n = 88; P < 0.01]. DRS-R98 and CTD scores were higher in irreversible delirium (P < 0.001) with greater disturbances of sleep, language, long-term memory, attention, vigilance and visuospatial ability. Irreversible delirium was associated with greater disturbance of CTD attention and higher DRS-R98 visuospatial function. Survival time was predicted by CTD score (P < 0.001), age (P = 0.01) and organ failure (P = 0.01). Delirium was not necessarily a harbinger of imminent death. Less reversible delirium involved greater impairment of attention, vigilance and visuospatial function. Survival time is related to age, severity of cognitive impairment and evidence of organ failure.     

Single-dose pharmacokinetics of multilayer-release methylphenidate and immediate-release methylphenidate in children with attention-deficit/hyperactivity disorder

The objective of this study was to compare the single-dose pharmacokinetics of multilayer-release and immediate-release methylphenidate in children with attention-deficit/hyperactivity disorder. Patients 6- to 12-years-old with a DSM-IV diagnosis of attention-deficit/hyperactivity disorder were randomized to receive multilayer-release methylphenidate (qd) or immediate-release methylphenidate (bid) at equivalent doses, with a 14-day washout between treatments. Plasma samples were collected predosing and 1, 2, 3, 4, 5, 6, 8, 10, 12, and 24 hours postdose. Pharmacokinetic analysis was conducted on 14 patients (1 female, 13 male; mean age: 9.6 +/- 2.5 years [range, 6-12]). The mean dose of methylphenidate received by these patients in both phases of the study was 38.6 mg/d (range, 20-80 mg/d). The relative AUC(0-t) and C(max 0-4) ratios for multilayer-release compared with immediate-release methylphenidate were 100.8% and 78.8%, respectively. Multilayer-release methylphenidate produces a biphasic concentration-time profile, with a rapid initial increase in plasma concentration that is maintained throughout the school day.