Rates of elastic compression stockings prescription following the diagnosis of deep venous thrombosis among Canadian emergency physicians and trainees.

UNLABELLED: Introduction Postthrombotic syndrome (PTS) is a complication of deep vein thrombosis (DVT) characterized by chronic pain, swelling, and heaviness, and may result in ulceration. Elastic compression stockings (ECS) worn daily after DVT have been shown to reduce the incidence and severity of PTS. The aim of our study was to investigate practices and perceptions of physicians regarding adjunct therapies to anticoagulation in patients diagnosed with lower extremity DVT. METHODS: A national online survey was conducted of Canadian emergency medicine staff physicians and residents (n=471) to investigate their attitudes toward the prescription of ECS post-diagnosis of DVT. A paper survey of patients in a thrombosis clinic (n=58) was also administered to better understand the patient experiences with ECS. RESULTS: The majority of staff physician (62%) and resident (69%) respondents were unsure of whether ECS were effective in preventing PTS and managing venous symptoms. Only 6% of staff physicians and 7% of residents routinely prescribed ECS for above-knee DVTs. More than 78% of respondents were unsure about the optimal timing of initiation of ECS and duration of therapy. Although all patients noted symptomatic relief with ECS, only 50% were prescribed stockings by an emergency or family doctor, and 69% of those patients wore the stockings on a daily basis. Staff physicians most frequently identified poor fit as the reason for lack of patient compliance, whereas patients most frequently cited cost. CONCLUSIONS: Our findings suggest that there is variability in practice among Canadian emergency medicine physicians and trainees and a need for widespread education regarding the latest evidence of the benefit of ECS after DVT.

Behavioral evidence for photophobia and stress-related ipsilateral head pain in transgenic Cacna1a mutant mice.

Migraine is a highly prevalent, disabling and complex episodic brain disorder whose pathogenesis is poorly understood, due in part to the lack of valid animal models. Here we report behavioral evidence of hallmark migraine features, photophobia and unilateral head pain, in transgenic knock-in mice bearing human familial hemiplegic migraine, type 1 (FHM-1) gain-of-function missense mutations (R192Q or S218L) in the Cacna1a gene encoding the CaV2.1 calcium channel α1 subunit. Photophobia was demonstrated using a modified elevated plus maze in which the safe closed arms were brightly illuminated; mutant mice avoided the light despite showing no differences in the standard (anxiety) version of the test. Multiple behavioral measures suggestive of spontaneous head pain were found in 192Q mutants subjected to novelty and/or restraint stress. These behaviors were: (1) more frequent in mutant versus wildtype mice; (2) lateralized in mutant but not in wildtype mice; (3) more frequent in females versus males; and (4) dose-dependently normalized by systemic administration of 2 different acute analgesics, rizatriptan and morphine. Furthermore, some of these behaviors were found to be more frequent and severe in 218L compared to 192Q mutants, consistent with the clinical presentation in humans. We suggest that Cacna1a transgenic mice can experience migraine-related head pain and can thus serve as unique tools to study the pathogenesis of migraine and test novel antimigraine agents.

Social modulation of pain as evidence for empathy in mice.

Empathy is thought to be unique to higher primates, possibly to humans alone. We report the modulation of pain sensitivity in mice produced solely by exposure to their cagemates, but not to strangers, in pain. Mice tested in dyads and given an identical noxious stimulus displayed increased pain behaviors with statistically greater co-occurrence, effects dependent on visual observation. When familiar mice were given noxious stimuli of different intensities, their pain behavior was influenced by their neighbor's status bidirectionally. Finally, observation of a cagemate in pain altered pain sensitivity of an entirely different modality, suggesting that nociceptive mechanisms in general are sensitized.