The effects of cardiopulmonary bypass temperature on neuropsychologic outcome after coronary artery operations: a prospective randomized trial.

UNLABELLED: The effect of systemic perfusion temperature on postoperative cognitive function was investigated in 96 adult patients undergoing elective coronary revascularization with cardiopulmonary bypass at 28 degrees C, 32 degrees C, or 37 degrees C. Neuropsychologic performance was assessed 1 day before the operation and 6 weeks after the operation. Five tests were adapted from the Wechsler Adult Intelligence Scale and two from the Wechsler Memory Scale. RESULTS: No patients had major neurologic complications. Ninety-three patients completed the five Wechsler Adult Intelligence Scale tests, but only 70 went on to complete the Wechsler Memory Scale tests as well. In these, there was an effect of cardiopulmonary bypass temperature on the number of neuropsychologic tests in which there was a preoperative to postoperative deterioration (p = 0.021), the number with bypass at 37 degrees C being significantly greater than the number with bypass at 32 degrees C (p = 0.015). Subsidiary analyses using a multivariate linear model examined the effect of cardiopulmonary bypass temperature on the magnitude of change, with or without allowing for other possible confounding influences. There was an adverse effect of normothermic (37 degrees C) versus moderately hypothermic (32 degrees C) perfusion---more convincingly displayed in the analyses of all seven scores rather than just the Wechsler Adult Intelligence Scale scores. Further cooling to 28 degrees C conferred no additional benefit in terms of cognitive function. The importance of the deterioration is open to question.

Empirical estimators of gamma fits to tracer-dilution curves and their technical basis and practical scope.

A gamma fit facilitates smoothing and extrapolation of distorted tracer-dilution curves in blood flow studies. Theoretically based empirical estimators were developed as simple alternatives to direct regression approaches from simulated gamma distributions with a wide range of shape asymmetry. Key curve features of peak height p, full width w at half peak height, rising and falling limb inflection tangents and asymmetry of the peak time with respect to the p/2 height occurrences were related to the parameters of the distribution by multiple linear regression after suitable transformations. The product pw was simply related to the total area A under the curve, pw/A being 0.93 +/- 0.01 in 70 cardiac output determinations from ten surgical patients. Shape and scale parameters were closely related to the standard deviation, inflection point properties and w for the curves. Mensuration devices suitable for cardiac output computers were developed that calculated total areas from incomplete portions under gamma curves and by-passed the need for parameter estimation. There was limited point in estimating the distribution parameters just to derive particle transit times, because of the ad hoc nature of the fitting form, which did not allow for the back-dispersion by Brownian motion of tracer molecules diluting in blood flow. Nonetheless, the accuracy of area prediction using a gamma fit was adequate for most clinical purposes and comparable to that via the random walk function, giving good insight to established results and computing procedures.

Promotion of condom use in a high-risk setting in Nicaragua: a randomised controlled trial.

BACKGROUND: In Latin America, motels rent rooms for commercial and non-commercial sex. We investigated the impact of providing health-education material and condoms on condom use in Managua, Nicaragua. METHODS: In a randomised controlled trial, in 19 motels, we gave condoms on request, made them available in rooms, or gave condoms directly to couples, with and without the presence of health-education material in the rooms. In a factorial design we assessed condom use directly by searching the rooms after couples had left. FINDINGS: 11 motels were used mainly by sex workers and their clients and eight mainly for non-commercial sex. 6463 couples attended the motels in 24 days. On 3106 (48.0%) occasions, at least one used condom was retrieved. Condom use was more frequent for commercial sex than for non-commercial sex (60.5 vs 20.2%). The presence of health-education material lowered the frequency of condom use for commercial sex (odds ratio 0.89 [95% CI 0.84-0.94]) and had no effect on use for non-commercial sex (1.03 [0.97-1.08]). Condom use increased for commercial (1.31 [1.09-1.75]) and non-commercial sex (1.81 (1.14-2.81) if condoms were available in rooms. Directly handing condoms to couples was similarly effective for commercial sex but less effective for non-commercial sex (1.32 [1.03-1.61] vs 1.52 [1.01-2.38]). INTERPRETATION: In Latin America, motels are key locations for promoting the use of condoms. Making condoms available in rooms is the most effective strategy to increase condom use, whereas use of health-education material was ineffective. These findings have important implications for HIV-prevention policies.

A randomized controlled trial of intracameral lidocaine during phacoemulsification under topical anesthesia.

OBJECTIVE: To test the hypothesis that adjunctive intracameral 1% lidocaine reduces intraoperative pain during phacoemulsification using topical anesthesia. DESIGN: Prospective, double-masked, randomized, controlled trial. PARTICIPANTS: A total of 200 patients undergoing routine phacoemulsification under topical 1% tetracaine were studied. INTERVENTION: Randomization to 0.5 ml intracameral, unpreserved, epinephrine-free 1% lidocaine or placebo was conducted. MAIN OUTCOME MEASURE: Intraoperative pain was quantified by the patients using a 0-10 visual analog pain scale. RESULTS: Intraoperative pain scores (+/- standard deviation) for the lidocaine and control groups were 1.29 +/-1.24 and 1.44 +/- 1.33, respectively (P > 0.35). CONCLUSIONS: In a rigorously double-masked, prospective, randomized, controlled trial there was no significant reduction in intraoperative pain when intracameral 1% lidocaine was used during phacoemulsification under topical anesthesia.

Suicide and unemployment in young people. Analysis of trends in England and Wales, 1921-1995.

BACKGROUND: The influence of the macro-economic climate on suicide is unclear. During the recent recession, rates have increased in young males but declined in females. AIMS: To investigate associations between unemployment and suicide in 15- to 44-year-old men and women over a period spanning two major economic recessions (1921-1995). To minimise confounding by changes in method availability, analyses are restricted to suicides using methods other than poisons and gases. METHOD: Time-series analysis using routine mortality and unemployment data. RESULTS: There were significant associations between unemployment and suicide in both males and females. Associations were generally stronger at younger ages. CONCLUSIONS: Secular trends in youth suicide may be influenced by unemployment or other factors associated with changes in the macro-economic climate. These factors appear to affect women to the same extent as men. Although it is not possible to draw firm aetiological conclusions from time-trend data, our findings are in keeping with those of person-based studies.