Bedside safety rails: assessment of strength requirements and the appropriateness of current designs.

Bedside safety rails are used extensively throughout hospitals and residential care environments as a safety device to protect people against the risk of falling out of bed. However, several adverse incidents involving body entrapment have been linked to their use, which have resulted in serious injury to the bed occupants and, in more extreme cases, fatalities. Internationally agreed standards (i.e. European Committee for Standardisation (CEN) standards) for the design and testing of bed rails have recently been developed and are targeted at improved safety requirements (European Committee for Standardisation 19972000). The purpose of the present study was to: 1) determine whether the CEN test procedure for assessing bed rail strength and rigidity requirements is consistent with human force exertions to which bed rails may be exposed; 2) carry out loading tests on bed rails currently in use throughout the UK to determine whether they comply with the current safety recommendations proposed by the CEN standards.A laboratory study was conducted to determine the force exertions of 20 participants performing seven tasks (including activities of both bed occupants and care providers), which were considered representative of the forces to which bed rails could be exposed during normal use. Forces exerted by participants were measured using a force platform and distortions of the bed rails leading to potential entrapment zones were measured using linear displacement transducers. Static load tests were then conducted, in which incremental point loading was applied at the most adverse points on each of nine different bed rails (commonly used in UK nursing and residential care homes) in accordance with the test procedure detailed in the current CEN standards. Maximum static forces exerted by participants were found to range between 250 N and 350 N, which were within the 500 N force tolerance requirements set by the standards. Dynamic tasks involving 'rolling aggressively' against the bed rail produced the highest peak force of 722 N. None of the bed rails included in this study met the requirements of the CEN test procedures, principally due to horizontal lateral displacements being in excess of 50 mm for a 500 N applied force and/or the bed rails' inability to withstand inward horizontal forces of 500 N. Bed rails used with divan beds were often unable to withstand forces greater than 300 N due to turning moments exceeding the bed rail's restraining mechanism. Current CEN standards for assessing the strength and rigidity of bedside safety rails appear to be consistent with the human forces that might arise as a consequence of the normal movement and activities of a bed occupant or care provider. Although compliance with existing standards is not compulsory, findings from the tests carried out on the selection of bed rails in current use throughout the UK highlight the need for improvements in the design and manufacture of bed rails.

Dacron vs vein for femoropopliteal arterial bypass. Should the saphenous vein be spared?

The increasing need for the saphenous vein to bypass lesions of the coronary and other small arteries prompts a reconsideration of its routine use for femoropopliteal bypass. Evaluation after five years in 124 consecutive patients (135 procedures) demonstrated no significant difference in overall definitive patency between venous grafts (63%) and Dacron prostheses (65%). Dacron prostheses were avoided when below-knee anastomoses were required, but when the distal anastomoses were made above the knee, the five-year patency for veins and Dacron was equal (67%). Although the quality of the distal runoff influenced the long-term patency, effects were similar for veins and for Dacron. The data support the use of Dacron prostheses for femoropopliteal bypass proximal to the knee joint, allowing preservation of the saphenous vein for possible use elsewhere.

Atrioventricular sequential pacemakers: indications, complications, and long-term follow-up.

Our experience with 32 patients with atrioventricular (AV) sequential pacemakers and an average follow-up of 22 months is presented. The pertinent literature and physiology are reviewed. The indications, advantages, and complications of AV sequential pacemakers are analyzed. Half of the patients required bifocal pacing for control of arrhythmia alone, while half required control of arrhythmia associated with congestive heart failure due primarily to a noncompliant left ventricle. It is anticipated that the hemodynamic improvement occurring as a results of AV sequential pacing will increase the use of this mode of cardiac pacing in selected patients.

Failure of Dacron prostheses caused by structural defect.

Intrinsic prosthetic failure is quite uncommon since the advent of Dacron prostheses. Only 24 cases of arterial prosthetic failure have been described in the literature. Our experience consists of two additional failures of knitted Dacron prostheses. The first patient developed aortojejunal fistula due to a defect of the aortic prosthesis 6 years after resection and replacement of an abdominal aortic aneurysm. The analysis of the graft revealed a defect in the form of a dropped stitch, which caused a weak spot where the prosthesis was able to be torn apart longitudinally. The second patient had femoropopliteal bypass and 6 years later developed degeneration with aneurysmal formation of the entire length of the prosthesis. Optical microscopy of this prosthesis exhibited mostly transverse failures which were coincident with valleys of the corrugated prosthesis. This was indicative of a defect that rendered the corrugation root too weak to withstand normal arterial pressures. This presentation emphasizes the seldom and serious complication of prosthetic failure due to defect of the prosthetic material. Details of scanning electron microscopy of the prosthesis, clinical presentation, angiography, and pathological findings with treatment also are discussed.

Survival and limb salvage in patients with infected arterial prostheses.

A series of 590 cases with a 2.5% rate of infection of arterial prostheses is presented. When one of the anastomoses was in the inguinal area, the incidence of prosthetic infection was higher. Two infections not involving the anastomotic site healed with conservative management. The three patients with aortoduodenal fistulas died. The long-term survival was 62%, and the amputation rate was 31%. During the last two years, a more aggressive surgical approach of total removal of the infected prosthesis and its replacement with an extraanatomic bypass has been instituted. With this approach, only one death and one amputation has occurred in six patients.