American Association of Critical-Care Nurses' national survey of facilities and units providing critical care.

BACKGROUND: Little information is available nationally about critical care units and nurses. What is known about nurses in hospitals is generally not broken down among all the specialties. OBJECTIVES: To describe issues of workforce, compensation, and care specific to critical care units and nurses who work in them. METHODS: The American Association of Critical-Care Nurses conducted a survey of randomly selected facilities with critical care units in the United States. Facilities were solicited via e-mail to respond to a survey on the World Wide Web and provide information on operations, evaluations, nursing staff reimbursement and incentives, staffing, and quality indicators. Responding facilities also provided contact information for units in the facilities. Those units were surveyed about operations, acuity systems, staffing, policies on visitation and end-of-life care, administrative structure, documentation, certification, professional advancement, vacancy/floating, staff satisfaction, orientation, association membership, wages, advanced practice nursing, and quality indicators. RESULTS: The initial response rate (120 of 658 eligible facilities) was 18.2%, and 300 of 576 solicited units nominated by the facilities responded, yielding a 52.1% response rate for the second phase. CONCLUSIONS: These survey data define the scope and intensity of services offered and provide more specific figures about staffing issues and unit practices than has been accessible before. Healthcare providers may use this information for benchmarking purposes, especially for instances in which the tables provide data for each particular type of critical care unit.     

Verifikation und Anwendungen des voxelbasierten Monte-Carlo-(VMC++-)Elektronen-Dosismoduls von Oncentra™ MasterPlan

PURPOSE, MATERIAL AND METHODS: The dose calculation accuracy of the voxel-based Monte Carlo (VMC++) electron dose module of Oncentra MasterPlan (Nucletron B.V., Veenendaal, The Netherlands) was verified by measurements in homogeneous water phantoms. RESULTS: Measured and calculated dose maxima on the central beam axis (calculations with 10,000-20,000 incident electron histories per cm(2)) agree well using standard applicator configurations as well as individually shaped inserts. Profile scans with higher electron energies (>/= 15 MeV) reveal differences up to 5% especially in the penumbra region. Depth dose curves agree best in the vicinity of maximum depths. In the buildup region energy-dependent differences up to 5% in both directions could be observed. In the decay region of depth dose curves calculated doses were up to 10% higher than measured values. CONCLUSION: Good VMC++ accuracy combined with moderate computing times of 1-15 min per beam satisfy all clinical needs. VMC++ allows, for the first time, accurate routine dose evaluations of radiation therapy with electrons. Adequate positioning of the dose reference point is essential. Even small displacements may significantly influence the calculation of monitor units.     

Promotion of mindfulness in psychotherapists in training: preliminary study.

This study examined whether the promotion of mindfulness in psychotherapists in training can influence the treatment results of their patients. The therapeutic course and treatment results of 196 inpatients, who were treated during a nine week period by nine psychotherapists in training, were compared: in the first phase of the study, the treatment group without (CG, historical control group, n=55), and in the second phase the treatment group with, (MFG, n=58) therapists who were currently practicing Zen meditation. The results of treatment were examined (according to the intent-to-treat principle) with the Session Questionnaire for General and Differential Individual Psychotherapy (STEP), the Questionnaire of Changes in Experience and Behaviour (VEV) and the Symptom Checklist (SCL-90-R), and showed significantly better results in the MFG.     

Double-crowned valved stents for off-pump mitral valve replacement.

OBJECTIVE: An animal model has been designed to assess the feasibility of off-pump mitral valve replacement using valved stents. METHODS: Glutaraldehyde-preserved homograft was sutured inside a prosthetic tube (Dacron). Then, two self-expandable nitinol Z-stents were sutured on the external surface of the prosthesis in such a way to create two self-expanding crowns for fixation. In adult pigs and under general anesthesia, the left atrium was exposed through a left thoracotomy and atrio-ventricular roadmapping was performed with intravascular ultrasound (IVUS) and fluoroscopy. The double-crowned valved stents were loaded into a delivery sheath. The sheath was then introduced into the left atrium and the valved stents was deployed in mitral position in such a way that the part in between the two stents was at the level of the mitral annulus. Intracardiac Unltrasound (ICUS) was used to assess the valve function. Hemodynamic parameters were gathered as well. Animal survived for no more than 3h after the valve deployment and gross anatomy examination of the left heart was carried out. RESULTS: The mean height of the valved stents was 29.4+/-0.2 mm, with an internal diameter of 20.4+/-1.0mm, and an external diameter of 25.5+/-0.8 mm. The procedure was successfully carried out in eight animals. In vivo evaluation showed a native mitral annulus diameter of 24.9+/-0.6 mm, and a mean mitral valve area of 421.4+/-17.5 mm2. ICUS showed a mild mitral regurgitation in three out of eight animals. Mean pressure gradient across the valved stents was 2.6+/-3.1 mmHg. Mean pressure gradient across the left ventricular outflow tract (LVOT) was 6.6+/-5.2 mmHg. The mean survival time was 97.5+/-56.3 min (survival time range was 40-180 min). One animal died due to the occlusion of the LVOT because of valved stents displacement. Postmortem evaluation confirmed correct positioning of the valved stent in the mitral position in seven out of eight animals. No atrial or ventricular lesions due to the valved stents were found. CONCLUSIONS: Off-pump implantation of a self-expandable valved stent in the mitral position is technically feasible. Further studies will assess if this procedure is also feasible in humans.     

Kaiserschnitt auf Verlangen?

Ohne Zusammenfassung     

Perioperative tumor localization for laparoscopic colorectal surgery

Background: Because of the inability to palpate colonic tumors during laparoscopy, their location must be precisely identified before resection is undertaken. Method: A retrospective study was performed of 58 patients in order to be able to describe our methods of tumor localization for laparoscopic colorectal operations and to review their effectiveness. Results: In all patients, the entire colon was examined preoperatively by colonoscopy. In one patient, preoperative colonoscopic localization was inaccurate. In 31 patients, tumors were easily detectable at surgery. In five patients with the tumor in the right colon, even though the lesion was not detectable at surgery, right colectomy was performed without marking because preoperative colonoscopy reliably identified the lesion adjacent to the ileocecal valve. Twenty-two patients required some type of procedure to localize the tumor. The procedures and their problems were as follows: preoperative tattoo (five)—tattoo not visualized (one); intraoperative colonoscopy alone (six), combined with intraoperative tattoo (four) or clip (three)—poor operative exposure due to bowel distension (nine), hard to see the clip (three), dislodged clip (two), inadequate resection margin (one); intraoperative proctoscopy alone (two), combined with laparoscopic stitch (two)—no problems. In no patient was tumor present at a resection line and in no patient was the wrong segment resected. Conclusions: Reliable preoperative identification of the tumor adjacent to the ileocecal valve can permit right colectomy without marking. Lesions in the upper rectum can be approached via intraoperative proctoscopy ± suture placement. If the surgeon anticipates intraoperative localization may be difficult, lesions other than rectal or cecal ones should probably be marked by preoperative tattooing. Further studies regarding the technique of tattooing are warranted. Received: 18 July 1996/Accepted: 10 March 1997     

Physicochemical aspects of drug release. XV. Investigation of diffusional transport in dissolution of suspended, sparingly soluble drugs

The dissolution rates of sparingly soluble, fine particulate, suspended drugs have been studied using a Coulter Counter Model TAII. For two sieve fractions of oxazepam the dissolution rates were monitored in media with varying viscosities brought about by the addition of glycerol, while for griseofulvin the change in the medium's viscosity was induced by changing the temperature. By calculating the dissolution rate, and compensating for differences in particle surface area and media solubility, it was shown that the dissolution rate was diffusion controlled. After additional normalization for the diffusion coefficient, it was suggested that the so-called apparent diffusional distance decreased substantially with particle size. The effect of particle size was more limited above approx. 15 μm.