The influence of lung volume reduction surgery on exercise in patients with COPD.

Although the influence of lung volume reduction surgery (LVRS) on incremental- and constant-power exercise is important in the evaluation of this procedure for patients with chronic obstructive pulmonary disease (COPD), it is rarely reported even in large randomised controlled trials. This report describes 39 patients with severe COPD ((mean +/- SE) forced expiratory volume in one second 32 +/- 2% pred, functional residual capacity 195 +/- 6% pred) who participated in a randomised controlled trial of LVRS and who completed incremental exercise tests at 6 months as well as endurance tests (constant power of 25 +/- 1 W) at 3, 9 and 12 months. Peak oxygen uptake (V'O2,pk) was similar between the treatment (n = 19) and control groups (n = 20) at baseline. After LVRS, the treatment group had a significantly greater V'O2,pk (mean difference (95% CI) 1.28 (0.07-2.50) mL x kg x min(-1)) and power (13 (6-20) W). The treatment group achieved a significantly greater minute ventilation (7.1 (2.9-11.3) L x min(-1)) with a greater tidal volume (0.16 (0.04-0.28) L). Baseline endurance was similar between groups. After surgery, there were significant between-group differences in endurance time, which were maintained at 12 months (7.3 (3.9-10.8) min). Lung volume reduction surgery is associated with an increase in exercise capacity and endurance, as compared with conventional medical treatment.     

Devolution of hip and knee replacement surgery?

The objectives of this study were to assess trends in referral patterns for joint replacements (JRs) in Ontario between the fiscal year 1988/89 and the fiscal year 1993/94; to assess the redistribution of financial resources if services were provided to residents in the region where they reside; and to estimate the financial implications of the devolution of primary JRs from tertiary-care hospitals to community hospitals. Despite rapid growth in the provision of JRs, there was no significant change in their regional distribution. Community hospitals have increased their share of JRs at the expense of teaching hospitals. For hospitals located in Central east Ontario, the cost of providing JRs to nonresidents increased from $5.9 million in 1988/89 to $8.3 million in 1993/94. Devolution of primary JRs requires a minimum reallocation sum of $25.1 million, with potential cost savings of $4.3 million. Many obstacles limit the devolution and local provision of health care services, including modifications to referral patterns and the availability of provider expertise, especially when a substantial redistribution of resources is required. Better clinical data to evaluate outcomes and better patient-specific costing data are required. Devolution of services should be addressed in the context of appropriate institutional compensation for medical education.     

Incompatibility of contrast agents with intravascular medications. Work in progress

In vitro and in vivo precipitation of iodinated contrast agents when ioxaglate and papaverine are given together has been reported. To verify these reports and to investigate other medications not previously tested, the authors analyzed mixtures of contrast agents and medications in vitro with a light spectrophotometer and observed them for visible precipitates for up to 120 minutes. Previously reported incompatibilities between ionic or low-osmolality contrast media and medications were verified, and several new incompatibilities were discovered. No incompatibilities were found when the drugs tested were mixed with the new nonionic contrast media.