Is General Anesthesia for Endovascular Thrombectomy Helpful or Harmful?

Endovascular thrombectomy (EVT) has significantly improved outcomes for patients with acute ischemic stroke due to large vessel occlusion. However, despite advances, more than half of patients remain functionally dependent 3 months after their initial stroke. Anesthetic strategy may influence both the technical success of the procedure and overall outcomes. Conventionally, general anesthesia (GA) has been widely used for neuroendovascular procedures, particularly for the distal intracranial circulation, because the complete absence of movement has been considered imperative for procedural success and to minimize complications. In contrast, in patients with acute stroke undergoing EVT, the optimal anesthetic strategy is controversial. Nonrandomized studies suggest GA negatively affects outcomes while the more recent anesthesia-specific RCTs report improved or unchanged outcomes in patients managed with versus without GA, although these findings cannot be generalized to other EVT capable centers due to a number of limitations. Potential explanations for these contrasting results will be addressed in this review including the effect of different anesthetic strategies on cerebral and systemic hemodynamics, revascularization times, and periprocedural complications.

Author Correction: Rice plants overexpressing OsEPF1 show reduced stomatal density and increased root cortical aerenchyma formation.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Rice plants overexpressing OsEPF1 show reduced stomatal density and increased root cortical aerenchyma formation.

Stomata are adjustable pores in the aerial epidermis of plants. The role of stomata is usually described in terms of the trade-off between CO2 uptake and water loss. Little consideration has been given to their interaction with below-ground development or diffusion of other gases. We overexpressed the rice EPIDERMAL PATTERNING FACTOR1 (OsEPF1) to produce rice plants with reduced stomatal densities, resulting in lowered leaf stomatal conductance and enhanced water use efficiency. Surprisingly, we found that root cortical aerenchyma (RCA) is formed constitutively in OsEPF1OE lines regardless of tissue age and position. Aerenchyma is tissue containing air-spaces that can develop in the plant root during stressful conditions, e.g. oxygen deficiency when it functions to increase O2 diffusion from shoot to root. The relationship with stomata is unknown. We conclude that RCA development and stomatal development are linked by two possible mechanisms: first that reduced stomatal conductance inhibits the diffusion of oxygen to the root, creating an oxygen deficit and stimulating the formation of RCA, second that an unknown EPF signalling pathway may be involved. Our observations have fundamental implications for the understanding of whole plant gas diffusion and root-to-shoot signalling events.

Modulation of early stress-induced neurobiological changes: a review of behavioural and pharmacological interventions in animal models.

Childhood adversity alters the predisposition to psychiatric disorders later in life. Those with psychiatric conditions and a history of early adversity exhibit a higher incidence of treatment resistance compared with individuals with no such history. Modulation of the influence early stress exerts over neurobiology may help to prevent the development of psychiatric disorders in some cases, while attenuating the extent of treatment resistance in those with established psychiatric disorders. This review aims to critically evaluate the ability of behavioural, environmental and pharmacologic interventions to modulate neurobiological changes induced by early stress in animal models. Databases were systematically searched to locate literature relevant to this review. Early adversity was defined as stress that resulted from manipulation of the mother-infant relationship. Analysis was restricted to animal models to enable characterisation of how a given intervention altered specific neurobiological changes induced by early stress. A wide variety of changes in neurobiology due to early stress are amenable to intervention. Behavioural interventions in childhood, exercise in adolescence and administration of epigenetic-modifying drugs throughout life appear to best modulate cellar and behavioural alterations induced by childhood adversity. Other pharmacotherapies, such as endocannabinoid system modulators, anti-inflammatories and antidepressants can also influence these neurobiological and behavioural changes that result from early stress, although findings are less consistent at present and require further investigation. Further work is required to examine the influence that behavioural interventions, exercise and epigenetic-modifying drugs exert over alterations that occur following childhood stress in human studies, before possible translational into clinical practice is possible.

A Randomized Clinical Trial of Aquatic versus Land Exercise to Improve Balance, Function, and Quality of Life in Older Women with Osteoporosis.

PURPOSE: Despite the decreased gravitational loading that is experienced in an aquatic environment, little research has been conducted on this exercise medium for women with osteoporosis (OP). Aquatic exercise (AE) may improve function and balance, thus ultimately decreasing fall risk and the potential for hip fractures in this high-risk population. METHOD: A total of 68 women with OP, aged 60 years or older, were recruited into a randomized clinical trial evaluating the impact of AE, land exercise (LE), and no exercise (NE) on balance, functional mobility, and quality of life (QOL). RESULTS: Only one balance measure (backward tandem walk) significantly improved with AE compared to LE, but this did not translate into a greater improvement in self-report function. There were no significant differences between the exercise interventions and NE, except for in ratings of global change, where participants in the AE group were three times more likely to report improvement than those in the NE group. CONCLUSION: There were no differences in balance, function, or QOL in women with OP who followed an AE or LE programme compared to those in an NE control group. However, the significant differences in backward tandem walk between the AE and LE groups and self-reported global change between the AE and NE groups warrant further investigation. Significant improvements in balance and global change suggest that AE is a viable alternative for older women with OP who have difficulty exercising on land.

L-carnitine and exercise tolerance in medium-chain acyl-coenzyme A dehydrogenase (MCAD) deficiency: a pilot study.

Skeletal muscle function may be impaired in patients with medium-chain acyl-CoA dehydrogenase (MCAD) deficiency, but the value of L-carnitine in their long-term management is not clear. This study was designed as a pilot to examine the effects of L-carnitine on exercise tolerance in patients with MCAD deficiency. Four clinically asymoptomatic MCAD-deficient patients, aged 8 to 20 years, were studied. Incremental ramp exercise tests were carried out before and after 4 weeks' treatment with oral L-carnitine (100 mg/kg per day). During exercise without L-carnitine supplementation, plasma carnitine concentrations fell, associated with an increased excretion of urinary acylcarnitines, notably acetylcarnitine, hexanoylcarnitine and octanoylcarnitine. L-carnitine treatment prevented this fall in plasma carnitine and resulted in greater increases in excretion of acylcarnitines. All four patients showed biologically significant improvement in peak oxygen uptake (peak VO2, 18-32% improvement), VO2 at a heart rate of 170 beats/min (15-23% improvement), VO2 at anaerobic threshold (27-42% improvement), and/or oxygen pulse (10-32% improvement). Exercise tolerance in MCAD-deficient patients may be improved by short-term L-carnitine supplementation. This may be the direct result of improved intramitochondrial homeostasis induced by L-carnitine in removing accumulating acyl moieties.

Home versus center based physical activity programs in older adults.

BACKGROUND: Physical inactivity is a leading cause of preventable death and morbidity in developed countries. In addition physical activity can potentially be an effective treatment for various medical conditions (e.g. cardiovascular disease, osteoarthritis). Many types of physical activity programs exist ranging from simple home exercise programs to intense highly supervised hospital (center) based programs. OBJECTIVES: To assess the effectiveness of 'home based' versus 'center based' physical activity programs on the health of older adults. SEARCH STRATEGY: The reviewers searched the Cochrane Central Register of Controlled Trials (CENTRAL) (1991-present), MEDLINE (1966-Sept 2002), EMBASE (1988 to Sept 2002), CINAHL (1982-Sept 2002), Health Star (1975-Sept 2002), Dissertation Abstracts (1980 to Sept 2002), Sport Discus (1975-Sept 2002) and Science Citation Index (1975-Sept 2002), reference lists of relevant articles and contacted principal authors where possible. SELECTION CRITERIA: Randomised or quasi-randomised controlled trials of different physical activity interventions in older adults (50 years or older) comparing a 'home based' to a 'center based' exercise program. Study participants had to have either a recognised cardiovascular risk factor, or existing cardiovascular disease, or chronic obstructive airways disease (COPD) or osteoarthritis. Cardiac and post-operative programs within one year of the event were excluded. DATA COLLECTION AND ANALYSIS: Three reviewers selected and appraised the identified studies independently. Data from studies that then met the inclusion/exclusion criteria were extracted by two additional reviewers. MAIN RESULTS: Six trials including 224 participants who received a 'home based' exercise program and 148 who received a 'center based' exercise program were included in this review. Five studies were of medium quality and one poor. A meta-analysis was not undertaken given the heterogeneity of these studies. CARDIOVASCULAR. The largest trial (accounting for approximately 60% of the participants) looked at sedentary older adults. Three trials looked at patients with peripheral vascular disease (intermittent claudication). In patients with peripheral vascular disease center based programs were superior to home at improving distance walked and time to claudication pain at up to 6 months. However the risk of a training effect may be high. There are no longer term studies in this population. Notably home based programs appeared to have a significantly higher adherence rate than center based programs. However this was based primarily on the one study (with the highest quality rating of the studies found) of sedentary older adults. This showed an adherence rate of 68% in the home based program at two year follow-up compared with a 36% adherence in the center based group. There was essentially no difference in terms of treadmill performance or cardiovascular risk factors between groups. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). Two trials looked at older adults with COPD. In patients with COPD the evidence is conflicting. One study showed similar changes in various physiological measures at 3 months that persisted in the home based group up to 18 months but not in the center based group. The other study showed significantly better improvements in physiological measures in the center based group after 8 weeks but again the possibility of a training effect is high. OSTEOARTHRITIS. No studies were found. None of the studies dealt with measures of cost, or health service utilization. AUTHORS' CONCLUSIONS: In the short-term, center based programs are superior to home based programs in patients with PVD. There is a high possibility of a training effect however as the center based groups were trained primarily on treadmills (and the home based were not) and the outcome measures were treadmill based. There is conflicting evidence which is better in patients with COPD. Home based programs appear to be superior to center based programs in terms of the adherence to exercise (especially in the long-term).

Improvement in exercise tolerance in isovaleric acidaemia with L-carnitine therapy.

The effect of 4 weeks' treatment with oral-L-carnitine (100 mg/kg per day) on carnitine status and metabolic parameters during an incremental ramp exercise test in a 12-year-old girl with isovaleric acidaemia was examined to determine its possible therapeutic role. The maximum work rate achieved increased from 110 to 120 watts; oxygen consumption at anaerobic threshold from 600 to 800 L/min; peak oxygen consumption from 1270 to 1450 L/min; and oxygen pulse, a measure of cardiac output, from 7.0 to 8.1 L/beat. These changes were associated with increases in plasma and urinary free and acyl carnitine concentrations but no change in physical activity. This observed effect of L-carnitine on exercise performance may be on cardiac or skeletal muscle function or both. We conclude that, in this single patient with isovaleric acid-aemia, L-carnitine supplementation had objective benefits and further studies on more patients are warranted.

Evaluation of single-leg standing following anterior cruciate ligament surgery and rehabilitation.

BACKGROUND AND PURPOSE: Although surgical reconstruction of the anterior cruciate ligament (ACL) is commonly performed to increase stability of the knee, persistent changes in neuromuscular function have frequently been cited as contributing to disability. This study investigated single-leg standing balance in a sample of patients 10 to 18 months following reconstructive ACL surgery. In addition, the effect of leg dominance on standing balance was analyzed in a sample of subjects without knee injury. The validity and interrater reliability of a clinical method of measuring balance using observation were also determined. SUBJECTS: Seventy-eight subjects without knee injury and 17 patients following ACL surgery participated in the study after they had been screened for balance disorders. METHODS: Postural sway measurements were recorded during single-leg standing with the subjects' eyes open and closed. Simultaneously, two physical therapists graded each subject's performance using a simple ordinal scale. RESULTS: No differences were found between the dominant and nondominant legs of the subjects without knee injury or between the involved and noninvolved legs of the patients who had undergone ACL surgery. The interrater reliability was high, but limited concurrent validity was found. CONCLUSION AND DISCUSSION: The findings suggest that single-leg standing balance can be reliably evaluated by physical therapists. The single-leg standing balance test, however, may not provide information that assists clinicians in determining clinical change or functional level for patients following rehabilitation for ACL surgery.

Dental injuries at the 1989 Canada games: an epidemiological study.

The management and prevention of dental trauma is an integral part of the medical services provided at major athletic events. This paper reviews the organization and delivery of the dental services provided at the 1989 Canada Games. The nature, incidence and management of the dental problems reported in the participant population of 3,411 athletes are also described. During the two-week competition, 15 participants were assessed and treated for various dental conditions, including hard- and soft-tissue injury of the oral cavity, and temporomandibular joint sprain. The sports with the highest incidence of dental injury for the male population were wrestling (one per cent) and basketball (0.8 per cent). For the female population, these sports were basketball (2.5 per cent) and field hockey (1.3 per cent). The dental services provided during the games included emergency assessment and treatment, fabrication of mouthguards, and in-service education to medical team members.

Sports injury/illness reporting at major sporting events: development and implementation of a data collection system.

When a large number of athletes compete intensely over a short period of time, a variety of sports injuries and illnesses are often encountered. Maintaining health records at these events presents a challenge to medical organizing committees. Accurate data collection is important, not only for planning of medical services, but also for development of prevention programs and policies relating to athletes' health. Recruitment of a dedicated data collection team with sports medicine background and computer expertise will facilitate collection and analysis of medical data at this type of event. This paper reviews the development and implementation of a sports injury and illness recording system used at the 1989 Jeux Canada Summer Games. Over 3500 participants had access to comprehensive medical services during the two weeks of competitions. Information on medical encounters was available daily during the games and a final report on sports injuries and illnesses was easily generated.