The effect of irrigation time and type of irrigation fluid on cartilage surface friction.

It is known that fluid irrigation used during arthroscopic procedures causes a wash-out of lubricating substances from the articular cartilage surface and leads to increased friction. It was the goal of this study to investigate whether this effect depends on the time of irrigation and type of fluid used. Rabbit hind legs were used for the tests. The knees were dissected and the friction coefficient of the femoral cartilage measured against glass in a boundary lubrication state. To determine the influence of irrigation time and fluid, groups of 12 knees received either no irrigation (control), 15, 60 or 120min of irrigation with lactated Ringer's solution or 60min of irrigation with normal saline or a sorbitol/mannitol solution. The time of irrigation had a significant effect on the static and kinetic coefficient of friction (CoF), as had the type of fluid. Longer irrigation time with Ringer's solution was associated with increased friction coefficients (relative increase of the kinetic CoF compared to the control after 15, 60 and 120min: 16%, 76% and 88% respectively). The sorbitol/mannitol solution affected the static and kinetic CoF significantly less than either Ringer's or normal saline. The washout of lubricating glycoproteins from the cartilage surface and the associated increase of friction can be effectively influenced by controlling the time of irrigation and type of fluid used. The time of exposure to the irrigation fluid should be as short as possible and monosaccharide solutions might offer a benefit compared to salt solutions in terms of the resultant friction.

[The pharmacokinetics and metabolism of bonnecor in rats]. / Farmakokinetika i metabolizm bonnekora u krys.

The pharmacokinetics of 14C-bonnecor after intravenous and oral administration was studied. The bioavailability was 70%. It was shown that administration of doses in the range of from 3 to 43 mg/kg as well as the repeated use of bonnecor failed to influence the pharmacokinetic parameters.

From nursing to nursing administration: making the transition easier.

When nurses get involved in nursing administration, they may experience difficulties with the managerial role. There are several reasons why these difficulties occur: failure to recognize that the skills required for management are different than those required for nursing; refusing to "let go" of former nursing duties; inconsistent emphasis on the development of managerial capability among nursing supervisors; and insufficient formal training in management. Suggestions for making the transition to management easier are presented. These include developing the proper mix of skills for management; delegating authority properly; systematizing on-the-job-training for supervisors; and restructuring the formal academic preparation that nurses receive while in B.N. programs.

Organizational politics and nursing administration.

When attempts are made to improve organizational performance, both rational and emotional factors will have to be recognized. One of the important emotional factors is the tendency of people to behave politically while they are carrying out their assigned duties. The meaning and importance of organizational politics is discussed, and several typical reactions of nurse administrators to organizational politics are examined. Practical suggestions are made to help nurse administrators develop greater political sensitivity and deal effectively with political behavior.