Publications by authors named "Chris Yates"

Background And Importance: Patients who use recreational drugs frequently co-ingest ethanol, which is considered a central nervous system (CNS) depressant. The clinical relevance of this in acute toxicity involving other CNS depressants is not well described.

Objective: To assess the clinical impact of ethanol co-use in patients presenting to the emergency department (ED) with acute toxicity involving the use of CNS depressant drugs.

Design, Settings And Participants: A retrospective multicentre study using data from the Euro-DEN Plus database from January 2014 to December 2019.

Outcomes Measure And Analysis: Comparison of epidemiologic and clinical characteristics, ED and hospital management of patients with CNS depressant intoxication with or without ethanol co-use.

Main Results: Although 7644 (17.5%) of the 43 633 presentations were included, ethanol was co-ingested in 3811 (49.9%). In total 53.3% required medical treatment, 14 patients died. Patients with ethanol co-use more frequently presented with a Glasgow Coma Scale (GCS) ≤8 (34.1% vs. 22.4%; P  < 0.001), vomiting (8.1% vs. 4.6%; P  < 0.001), anxiety (12 % vs. 6.4%; P  < 0.001), agitation/aggression (22% vs. 14.7%; P  < 0.001), seizures (3.8% vs. 2.4%; P  < 0.001) and hypotension (7.5% vs. 4.6%; P  < 0.001). They more often required ambulance transport (85.5% vs. 76.5%; P  < 0.001), medical treatment (57.3% vs. 48.0%; P  < 0.001), hospitalization (27.7% vs. 18.9%; P  < 0.001), and admission to intensive care (12.2% vs. 4.0%; P  < 0.001). Subgroup analysis showed that GCS ≤8 was particularly common in patients who combined ethanol with opioids or gamma-hydroxybutyrate (GHB)/gamma-butyrolactone (GBL).

Conclusion: Co-use of ethanol with CNS-depressant drugs appears to increase the risk of adverse effects and is associated with a higher need for medical treatment, especially when ethanol is combined with opioids or GHB/GBL.

We present a range-gated camera system designed for real-time (10 Hz) 3D estimation underwater. The system uses a fast-shutter CMOS sensor (1280×1024) customized to facilitate gating with 1.67 ns (18.8 cm in water) delay steps relative to the triggering of a solid-state actively Q-switched 532 nm laser. A depth estimation algorithm has been carefully designed to handle the effects of light scattering in water, i.e., forward and backward scattering. The raw range-gated signal is carefully filtered to reduce noise while preserving the signal even in the presence of unwanted backscatter. The resulting signal is proportional to the number of photons that are reflected during a small time unit (range), and objects will show up as peaks in the filtered signal. We present a peak-finding algorithm that is robust to unwanted forward scatter peaks and at the same time can pick out distant peaks that are barely higher than peaks caused by sensor and intensity noise. Super-resolution is achieved by fitting a parabola around the peak, which we show can provide depth precision below 1 cm at high signal levels. We show depth estimation results when scanning a range of 8 m (typically 1-9 m) at 10 Hz. The results are dependent on the water quality. We are capable of estimating depth at distances of over 4.5 attenuation lengths when imaging high albedo targets at low attenuation lengths, and we achieve a depth resolution (σ) ranging from 0.8 to 9 cm, depending on signal level.