Restoring depleted coral-reef fish populations through recruitment enhancement: a proof of concept.

To determine whether enhancing the survival of new recruits is a sensible target for the restorative management of depleted coral-reef fish populations, settlement-stage ambon damsel fish Pomacentrus amboinensis were captured, tagged and then either released immediately onto small artificial reefs or held in aquaria for 1 week prior to release. Holding conditions were varied to determine whether they affected survival of fish: half the fish were held in bare tanks (non-enriched) and the other half in tanks containing coral and sand (enriched). Holding fish for this short period had a significantly positive effect on survivorship relative to the settlement-stage treatment group that were released immediately. The enrichment of holding conditions made no appreciable difference on the survival of fish once released onto the reef. It did, however, have a positive effect on the survival of fish while in captivity, thus supporting the case for the provision of simple environmental enrichment in fish husbandry. Collecting and holding settlement-stage fish for at least a week before release appear to increase the short-term survival of released fish; whether it is an effective method for longer-term enhancement of locally depleted coral-reef fish populations will require further study.

Plasma acid-base regulation above and below ventilatory threshold in late gestation.

Stewart's physicochemical approach was used to study the effects of pregnancy on acid-base regulation in arterialized blood. Responses of 15 healthy pregnant women (PG; gestational age, 37.1 +/- 0.2 wk) were compared with those of 15 nonpregnant controls (CG) at rest and during cycling at 70 and 110% of the ventilatory threshold (T(vent)). Hydrogen ion concentration ([H(+)]) was lower in the PG vs. CG at rest and during exercise (P < 0.05 at rest and 70% T(vent)). Exercise-induced changes in [H(+)] were similar between groups. Lower resting [H(+)] values in the PG vs. CG resulted from lower values for arterialized PCO(2) (Pa(CO(2))) and total weak acid ([A](tot)), which were partly offset by a lower strong-ion difference ([SID]). Reductions in [A](tot) and [SID] at rest were primarily the result of reductions in albumin [Alb] and sodium [Na(+)], respectively. In the transition from rest to 70% T(vent), small increases in Pa(CO(2)) and [A](tot) contributed to moderate increases in [H(+)] in both groups, however [SID] increased in the PG and decreased in the CG (P < 0.05 between groups). In the transition from rest to 110% T(vent), decreases in [SID] made a significantly greater contribution to changes in [H(+)] in the CG vs. PG. Exercise-induced increases in [H(+)] are similar in the pregnant vs. nonpregnant state, but there is a reduced contribution of [SID] both above and below T(vent) during pregnancy.

Maximal exercise testing in late gestation: maternal responses.

OBJECTIVE: To study the effects of human pregnancy on metabolic and respiratory responses to maximal cycle ergometer testing and to test the hypothesis that the respiratory exchange ratio at maximal exercise and peak postexercise lactate concentration are lower in the pregnant compared with the nonpregnant state and that these effects are associated with lower excess postexercise oxygen consumption during pregnancy. METHODS: The pregnant (n = 14, mean gestational age 34.7 +/- 0.4 weeks) and nonpregnant control group (n = 14) included healthy, physically active women. Groups were matched for age, height, parity, prepregnant body mass and body mass index (BMI), and aerobic fitness. Breath-by-breath gas exchange was measured at rest, during exercise, and 15 minutes after exercise. The minimum sample size to detect a statistically significant result for a reasonable difference (0.25 L/min) in the ventilatory threshold was calculated to be ten subjects per group; thus, 14 was considered adequate. RESULTS: Maximal oxygen uptake, the ventilatory threshold, the point of respiratory compensation, and calculated work efficiency did not differ significantly between groups. However, the respiratory exchange ratio at maximal exercise, peak postexercise lactate, and excess postexercise oxygen consumption were significantly lower in the pregnant group. Peak lactate was significantly correlated with the respiratory exchange ratio and excess postexercise oxygen consumption. CONCLUSION: The capacity for weight-supported work is preserved in late gestation, and work efficiency is unchanged. However, carbohydrate utilization might be blunted at high levels of exertion. Blunted respiratory responses were attributed to reduced lactate production and/or dilution of lactate in an expanded blood volume.

The influence of gender on the outcome of coronary artery bypass surgery.

BACKGROUND: To assess the impact of gender as an independent risk factor for early and late morbidity and mortality following coronary artery bypass surgery. METHODS: Perioperative and long-term data on all 4,823 patients undergoing isolated coronary bypass operations from November 1989 to July 1998 were analyzed. Of these patients, 932 (19.3%) were females. RESULTS: During the years 1989 to 1998 there was a progressive increase in the percentage of women undergoing coronary artery bypass surgery. The following preoperative risk factors were more prevalent among women than men: age above 70, angina class 3 or 4, urgent operation, preoperative intraaortic balloon pump usage, congestive heart failure, previous percutaneous transluminal coronary angioplasty, diabetes, hypertension, and peripheral vascular disease (all p < 0.05). Men were more likely to have an ejection fraction less than 35%, three-vessel disease, repeat operations, and a recent history of smoking. Women had a statistically significant smaller mean body surface area than men (1.72+/-0.18 versus 1.96%+/-0.26% m2). On average, women had fewer bypass grafts constructed than men (2.9%+/-0.8% versus 3.2%+/-0.9%) and were less likely to have internal mammary artery grafting (76.2% versus 86.1%), multiple arterial conduits (10.1% versus 19.8%), or coronary endarterectomy performed (4.9% versus 8.6%). The early mortality rate in women was 2.7% versus 1.8% in men (p = 0.09). Women were more prone to perioperative myocardial infarction (4.5% versus 3.1% p < 0.05). After adjustment for other risk variables, female gender was not an independent predictor of early mortality but was a weak independent predictor for the prespecified composite endpoint of death, perioperative myocardial infarction, intraaortic balloon counterpulsation pump insertion, or stroke (8.55 versus 5.9%; odds ratio, 1.30; 95% confidence interval, 0.99 to 1.68; p = 0.05) Recurrent angina class 3 or 4 was more frequent in female patients (15.2%+/-4.0% versus 8.5%+/-2.0% at 60 months, p = 0.001) but not repeat revascularization procedures (percutaneous transluminal coronary angioplasty, redo) (0.6%+/-0.3% versus 4.1%+/-0.8% at 60 months). Actuarial survival at 60 months was greater in women then men (93.1%+/-1.7% versus 90.0%+/-1.0%), and after adjustment for other risk variables, female gender was protective for late survival (risk ratio, 0.40; 95% confidence interval, 0.16-0.74; p < 0.005). CONCLUSIONS: Perioperative complications were increased and recurrent angina more frequent in women. Despite this, late survival was increased in women compared with men after adjustment for other risk variables

Reviews.

WOUND MANAGEMENT EDUCATION SYSTEM BODYWORKS 3.0 FOR DOS AND WINDOWS.

From the Journals.

Wound healing in the fetus Community management of patients with chronic leg ulcers Increase in malignant melanoma Pressure sore risk calculators Decreased immune responsiveness in older people.

Procedure gloves.

The US policy of 'universal precautions' treats all body fluids and excreta as an infection risk. Nurses have a responsibility to understand the rationale for glove use. Gloves play a major part in preventing cross-infection. The wearing of gloves is not a substitute for handwashing.

Devices for measuring blood glucose levels.

Monitoring blood glucose is as essential as ever. Technology has given real freedom to people with diabetes. The aim of diabetes management these days is simply to allow for a normal life. Nurses must keep abreast of all new developments.

Fluids used in total parenteral nutrition.

Parenteral nutrition is indicated for patients who cannot eat normally and for whom enteral feeding is inappropriate. TPN has an increasing role in home care for long-term conditions. The costs associated with TPN need to be considered in the context of patient benefits.

Emollient applications for chronic skin problems.

Emollients soothe and hydrate the skin. These products are the mainstay of treatment for contact dermatitis. Nurses do not need to be experts in dermatology but they do need to understand the principles and be able to advise on treatment options.

Handwashing solutions.

Handwashing is the most vital of all nursing procedures. Nurses can influence practice and purchasing decisions in handwashing. All the costs of handwashing need to be considered when choices are made.

Protein and energy food supplements.

Nurses must ensure that they are knowledgeable about nutrition--or the responsibility will be passed to untrained staff. There is a wide choice of food supplements, enabling cost-effective choices to be made.

Two-piece stoma systems.

Two-piece stoma appliances may not be suitable for all patients-- especially those with limited dexterity. For many, these systems can be quick, convenient and economic. The nurse's role is to ensure that the patient has a choice.