Reframing Future Risks of Extreme Heat in the United States.

The goal of this study is to reframe the analysis and discussion of extreme heat projections to improve communication of future extreme heat risks in the United States. We combine existing data from 31 of the Coupled Model Intercomparison Project Phase 5 models to examine future exposure to extreme heat for global average temperatures of 1.5, 2, 3, and 4 °C above a preindustrial baseline. We find that throughout the United States, historically rare extreme heat events become increasingly common in the future as global temperatures rise and that the depiction of exposure depends in large part on whether extreme heat is defined by absolute or relative metrics. For example, for a 4 °C global temperature rise, parts of the country may never see summertime temperatures in excess of 100 °F, but virtually all of the country is projected to experience more than 4 weeks per summer with temperatures exceeding their historical summertime maximum. All of the extreme temperature metrics we explored become more severe with increasing global average temperatures. However, a moderate climate scenario delays the impacts projected for a 3 °C world by almost a generation relative to the higher scenario and prevents the most extreme impacts projected for a 4 °C world.

Framing the work: development of a renal nursing professional practice model.

In 1997, a nursing care model task group was formed to develop a framework to guide the development of the nursing care delivery system in a newly merged hospital corporation. A collective group of experienced and motivated nurses in the renal program met to develop an integrated renal nursing professional practice model. In addition it was recognized that a city-wide model involving the two acute care renal centres would be advantageous. The challenge was to clearly articulate the professional roles and relationships of nurses and nurse practitioner/clinical nurse specialists in a constantly changing environment. This process provided the opportunity to identify key trends influencing renal care and possibilities for changing practice. Networking across the corporations was enhanced, partnerships were formed, and a sense of value for the work that was being undertaken developed. The group's endeavours resulted in an integrated nursing professional practice model that emphasizes accountability and continuity and places value on therapeutic relationships. Another strength of the model is the acknowledgement of the collaborative nature of the multidisciplinary team. After two years of development, the model was implemented. A city-wide Renal Nursing Professional Practice Council has been established in order to provide leadership in evaluating the model. This will include assessing the success of implementation, impact on patient/family care, and collaborative rewards experienced by staff. Future planning will address the potential need for a multidisciplinary focus within the practice council.

A comparison of methods for the measurement of hemodialysis access recirculation and access blood flow rate.

The ability to accurately measure access recirculation (AR) is of importance because its presence indicates access dysfunction and may explain why a prescribed Kt/V (urea) has not been delivered. The ability to measure access flow (Qa) allows access monitoring and the detection of impending access dysfunction. AR can be measured by indicator dilution or conductivity tracer techniques. Qa calculation is simple if AR can be detected. The previous techniques are used while the patient's blood lines are reversed to induce AR, and the Krivitski equation gives: Qa = Qb [1-r/r] where Qb = dialyzer blood flow and r = proportion of AR induced. Three methods for AR and Qa measurements were directly compared: 1) ultrasound dilution (Transonics Hemodialysis Monitor, Transonics Systems Incorporated) (TRANS); 2) hematocrit dilution (Crit-Line Monitor, In-Line Diagnostics) (CRIT); and 3) differential conductivity (Hemodynamic Monitor, GAMBRO Healthcare Incorporated) (HDM). Patients were cannulated in a standard fashion and dialysis commenced with lines in normal configuration. A HDM test was performed and, if AR = zero, the lines were reversed to induce AR. HDM, TRANS, and CRIT tests for AR were next done in rapid succession for direct comparison. Each test was repeated three times in succession, the device in random order, to assess test repeatability. Qb was taken from the 1) dialysis machine pump, and 2) directly from TRANS and Qa calculated, using 1) and 2) AR results. In comparison to TRANS, AR results were virtually identical for HDM (TRANS AR = 1.04 HDM-AR + 0.02, r = 0.98, p = 0.0000), and good for CRIT (CRIT-AR = 0.84 TRANS-AR - 0.2, r = 0.81, p = 0.001), but CRIT underestimated the values. Repeatability was assessed by normalizing (%) the SD of repeated measurements; values were 7.5% (HDM), 9.1 % (TRANS), and 17.4% (CRIT). Qa value comparisons were similar (minimal r = 0.83) regardless of Qb source, but CRIT overestimated the value; repeatability data showed 10.6% (HDM), 13.0% (TRANS), and 25.2% (CRIT) (n ranged from 15-64). In summary, TRANS and HDM appear equal as far as accuracy and repeatability of measurements; CRIT results correlated well, but tended to underestimate AR and overestimate Qa, and was less reproducible.

Accuracy and precision of access recirculation measurements by the hemodynamic recirculation monitor.

The hemodynamic monitor (HDM) is a device that uses magnetic principles to accurately measure access recirculation during hemodialysis. The measurement is based on differential conductivity between arterial and venous blood flow rates in the dialysis blood tubing sets. One milliliter of hypertonic saline is injected into the venous line of the blood tubing set as a conductivity "tracer." As the tracer enters the patient, the presence of access recirculation causes a percentage of the hypertonic saline to recirculate into the arterial line and is detected and quantified by the HDM; the percentage of access recirculation is calculated in under 1 minute. Clinical studies were performed in two centers on 106 patients with various forms of blood access (eg, arteriovenous fistulae, Gore-tex grafts [WL Gore and Associates, Flagstaff, AZ], Permcaths [Quinton Instrument Co, Bothell, WA], subclavian catheters). Access recirculation was detected under routine dialysis conditions in only 13 patients. In the remaining cases, attempts at inducing access recirculation were made by reversing the arterial and venous lines and/or increasing the blood pump to its maximum sustainable rate for a given patient. A 15-minute protocol was then instituted. Three blood samples (arterial, venous, and "peripheral" [stop-flow technique]) were first obtained to determine urea measurements and for subsequent calculation of access recirculation; immediately afterward, an HDM recirculation measurement was recorded to allow correlation of urea and HDM access recirculation results (accuracy). Two further HDM access recirculation measurements were made to analyze the precision or repeatability of the HDM test. This protocol was attempted up to three times in each patient on different dialysis days. Two hundred fifty-nine studies were made, and a strong linear correlation was obtained between urea and HDM results (r = 0.94, slope 0.95) over a range of access recirculation (5% to 60%) demonstrating accuracy. Repeated HDM access recirculation results showed a characteristic SD of 1.8% over the whole range of values, demonstrating a precision superior to the 6% expected using the urea method. When zero access recirculation was indicated by the HDM, "ground truth" tests were performed by injecting 1 mL of hypertonic saline (HS) into one injection port of the blood tubing set then 0.1 mL of HS into the other to simulate 10% access recirculation; the mean results were 9.96%+/-1.59% (+/-SD; n = 93), confirming the accuracy of the method.

Hemodialysis access blood flow rates can be measured by a differential conductivity technique and are predictive of access clotting.

Blood flow in peripheral arteriovenous fistulae and grafts as used for hemodialysis access can be derived from measurements of the amount of access recirculation induced by reversing the dialysis blood lines and a knowledge of the dialyzer blood flow rate. The Hemodynamic Monitor (HDM; GAMBRO Healthcare, Lakewood, CO) is a device that uses magnetic principles to accurately and precisely measure access recirculation during hemodialysis. The measurement is based on differential conductivity between arterial and venous blood flows in the dialysis blood tubing sets following the injection of hypertonic saline into the venous line as a conductivity tracer. Clinical studies were performed on 41 patients from two centers who had arteriovenous fistulae (25 patients) or Goretex grafts (16 patients; W.L. Gore & Associates, Flagstaff, AZ); each patient was studied on two successive dialysis days under variable conditions of dialyzer blood flow, and multiple measurements were made according to a standard protocol. The protocol involved temporarily reversing the arterial and venous lines, then performing an HDM recirculation test and recording the result along with the dialyzer blood flow rate as per the machine blood pump setting. The access blood flow rates measured 1,125+/-581 mL/min (mean+/-SD) on day 1 and 1,140+/-680 mL/ min on day 2 (P > 0.05 [NS]), with an absolute range of 221 to 3,118 mL/min. These flow rates are similar to those measured by other techniques. There was an excellent correlation between access blood flow rates measured in individual patients on days 1 and 2, even in a subset of 13 patients who had the dialyzer blood flow rates altered by > or =100 mL/min, suggesting the independence of access from dialyzer blood flow rates. Analysis of repeated measurements of access blood flow under identical conditions showed a characteristic standard deviation from the mean across the patient population of 7.89%, indicating that the HDM results are repeatable in clinical application. The influence of the measured access blood flow on the outcome of that access was determined after an 8-month follow-up period. Of the 41 accesses, nine were lost to clotting; seven of 14 that had initial blood flow rates less than 750 mL/min clotted, while only two of 27 with flow rates greater than 750 mL/min subsequently clotted (P = 0.005). The data show that the HDM can provide clinically important information on access blood flow.

Pain management guidelines: implications for managed care--a roundtable discussion.

One of the most important concerns of patients with cancer, particularly those with metastatic disease, is "Will I be in constant pain?" This is a similar concern voiced by patients with late-stage human immunodeficiency virus infection. The management of chronic pain has enormous implications on a patient's ability to function and on his or her quality of life. In June 1996, Medical Interface convened a panel of experts in Chicago to discuss pain management therapies, guidelines, and how these issues will affect, and be affected by, the managed care environment.

The mental health patient profile: does it change primary care physicians' practice patterns?

BACKGROUND: We conducted a prospective trial randomizing 75 physicians to either a control or intervention arm to evaluate the impact of providing patient-reported information on anxiety and other mental health symptoms and disorders to primary care physicians. METHODS: Five hundred seventy-three patients of the study physicians who met entry criteria were randomized to either usual care or usual care supplemented with feedback of patient-reported mental health information to physicians. This mental health information was derived from initial patient-reported questionnaires completed in waiting rooms of physicians contracted to a mixed-model health maintenance organization in Colorado. Main outcome measures included impact of intervention on rates of (1) chart notation of anxiety, depression, or other mental health diagnoses or symptoms; (2) referral to mental health specialists; (3) prescription of psychotropic medications; (4) hospitalization; and (5) office visits during a 5-month observation period. RESULTS: Physicians receiving feedback on previously unrecognized and untreated anxiety patients were more likely to make chart notations (adjusted odds ratio [AOR] = 2.51, 95 percent confidence interval [CI] = 1.62-3.87), to make referrals to mental health specialists (AOR = 3.86, 95 percent CI = 1.63-9.16), and to see patients for more frequent outpatient visits (AOR = 1.73, 95 percent CI = 1.11-2.70). Use of psychotropic medications and rate of hospitalizations did not differ significantly. CONCLUSIONS: Providing patient-reported mental health information to primary care physicians resulted in increased recognition and referral rates for previously unrecognized and untreated anxiety patients, plus an increase in primary care visits, without concomitant increases in the use of psychotropic medications or rate of hospitalizations.

Staff participation in administrative decision-making.

Victoria Hospital Corporation in London has adopted a collaborative management model that involves the participation of medical, union and non-union staff in the administrative decision-making process within predetermined parameters. Reactions have been favourable from all sides--positive feedback from the groups involved and minimal negative public response to the sensitive decisions made concerning downsizing. Early indicators suggest increasing further the participation of union and non-union staff in decision-making on multiple levels, but with clearly defined "boundaries of responsibility."

[Academician Vilém Laufberger and the Czechoslovak Academy of Sciences]. / Akademik Vilém Laufberger a CSAV.

Academician Vilém Laufberger participated in a significant way in the work of the Czechoslovak Academy of Sciences. He was one of its founders as a member of the preparatory commission for its establishment, an important official in its presidium, founder and director of one of its institutes and a permanent long-term critical observer and commentator of its activities. He greatly appreciated the steep rise of biomedical research at the beginnings of the Academy as a worthy development of the traditions of world reknown physiologists J. E. Purkyne and I. P. Pavlov. He evaluated favourably also its subsequent development. At the very beginning he drew attention to some shortcomings which during subsequent development influenced the activities of the Academy in an adverse way. Their elimination is a task for the present time.