Snowblading injuries in Eastern Canada.

OBJECTIVES: To evaluate injury patterns of snowbladers and compare them with those of skiers and snowboarders. To determine possible effects of helmet use in these sports on injury to the head and neck. METHODS: This prospective case series observational study was conducted by collecting the injury reports from the ski patrol during the 1999-2000 season at Mont Tremblant ski resort, Quebec. All participants in downhill winter sports who presented themselves to the ski patrol with traumatic injury related to their sport were included. A concussion was defined as any loss of consciousness, amnesia, confusion, disorientation, vertigo, or headache that resulted from injury. The ski patroller reported helmet use on the accident report at the time of injury. RESULTS: Snowbladers present with a unique pattern of injury compared with skiers and snowboarders. The incidence of leg, knee, and ankle/foot injuries were 20.5%, 25.6%, and 10.3% respectively. Concussions represented 11% of all injuries. There was no increase in other injury, including neck injury, related to helmet use. CONCLUSIONS: Unique injury patterns in snowbladers warrant reconsideration of equipment design. Concussion is a common injury on the ski slope. Although the effects of helmet use on concussion rate are inconclusive based on this study, helmet use did not increase the rate of neck injury, even when adjusted for age.

Cardiovascular chronobiology: do you know what time it is?

Cardiovascular indices, such as blood pressure, heart rate, cardiac output, and fibrinolytic factors, vary over a 24-hour period. For example, nocturnal blood pressure may decrease to 30-50 mm Hg and heart rate to 25 beats per minute. In addition, these cardiovascular rhythms interact and may trigger a cardiovascular catastrophe, such as a myocardial infarction, sudden cardiac arrest, or stroke, with the highest risk during the first 6 hours after awakening and arising. Understanding the fluctuations in cardiovascular indices and the rhythmic increase in risk is crucial in assessing patients and developing a protective plan of care. This article discusses the cardiovascular rhythms and the rhythmic increase in risk for cardiovascular catastrophes. A framework demonstrating the interaction of these rhythms provides the basis for the development and exploration of interventions, including modification of activity and medications, and nursing actions to protect patients during periods of high cardiovascular risk.

Effect of the 30 degree lateral recumbent position on pulmonary artery and pulmonary artery wedge pressures in critically ill adult cardiac surgery patients.

BACKGROUND: Despite demonstrated benefits of lateral positioning, critically ill patients may require prolonged supine positioning to obtain reproducible hemodynamic measurements. OBJECTIVES: TO determine the effect of 30 degree right and left lateral positions on pulmonary artery and pulmonary artery wedge pressures after cardiac surgery in critically ill adult patients. METHODS: An experimental repeated-measures design was used to study 35 patients with stable hemodynamics after cardiac surgery. Subjects were randomly assigned to 1 of 2 position sequences. Pulmonary artery and pulmonary artery wedge pressures were measured in each position. RESULTS: Measurements obtained from patients in the 30 degree left lateral position differed significantly (all Ps < .05) from measurements obtained from patients in the supine position for pulmonary artery systolic, end-diastolic, and mean pressures. Pulmonary artery wedge pressures did not differ significantly; however, data were available from only 17 subjects. The largest mean difference in pressures between the 2 positions was 2.0 +/- 2.1 mm Hg for pulmonary artery systolic pressures, whereas maximum differences for end-diastolic and pulmonary artery wedge pressures were 1.4 +/- 2.7 mm Hg and 1.6 +/- 2.4 mm Hg, respectively. Clinically significant position-related changes in pressure occurred in 12 (2.1%) of 581 pressure pairs. Clinically significant changes occurred in end-diastolic pressure in 2 subjects and in pulmonary artery wedge pressure in 1 subject. CONCLUSIONS: In patients with stable hemodynamics during the first 12 to 24 hours after cardiac surgery, measurements of pulmonary artery and pulmonary artery wedge pressures obtained in the 30 degree lateral and supine positions are clinically interchangeable.

Monitoring pulmonary artery pressures: just the facts.

Numerous research-based guidelines for PA pressure monitoring are available. Despite the availability of this large body of literature related to PA pressure monitoring, critical care nurses continue to demonstrate insufficient knowledge and ability to apply information related to the collection and interpretation of data obtained with a PA catheter. This article focuses on these problematic areas, and reinforces the need to continue to include the basic principles of PA pressure monitoring in education and training programs.

Cardiovascular chronobiology: implications for critical care nursing.

Critical care clinicians must consider known expected circadian rhythms when interpreting fluctuations in patients' hemodynamic values. As noted in the case study, knowledge of circadian rhythmicity in cardiovascular variables may help clinicians anticipate hemodynamic changes and develop and evaluate chronobiologically sensitive interventions, including prescriptions for activity, modification of the timing of medications, and provision of protective interventions for patients with disrupted rhythms. Felver provides excellent guidelines for the systematic review of possible causes for overt changes in circadian patterns. This review highlights the need to evaluate (1) the effect of disease progression on temporal patterns, (2) the patient's underlying endogenous rhythms, (3) the zeitgebers that may entrain the patient's biological rhythms (e.g., light, social cues, and sleep-wake cycles), and (4) how the zeitgebers change in a critical care environment. The body of literature on the rhythmic fluctuation of cardiovascular variables in healthy, young subjects is extensive. During the past 10 years, research on the chronobiologic fluctuations of numerous physiological variables (cardiovascular, pulmonary, hematologic, and endocrine) in critical illness has increased. As information on the fluctuations in critically ill patients increases, critical care clinicians will be challenged to develop and evaluate a chronobiologically sensitive plan of care for these patients.

Pulmonary artery pressure measurement: state of the art.

The measurement of pulmonary artery pressure is a highly complex skill. Numerous technical variables can affect the reliability and validity of hemodynamic measurements: zeroing, referencing and evaluating the dynamic response characteristics of the pressure system, expected pressure fluctuations, stabilization period, and the effects of position and ventilation. This article presents a review of the literature related to the technical aspects of pulmonary artery pressure measurement. Recommendations for practice are presented in a research-based protocol.