Ischemic postconditioning: brief ischemia during reperfusion converts persistent ventricular fibrillation into regular rhythm

Objectives: Brief episodes of myocardial ischemia-reperfusion employed during reperfusion after a prolonged ischemic insult may attenuate the total ischemia-reperfusion injury. This phenomenon has been termed ischemic postconditioning. In the present study, we studied the possible effect of postconditioning on persistent reperfusion-induced ventricular fibrillation (VF) in the isolated rat heart model. Methods: Isolated Langendorff-perfused rat hearts (n=46) were subjected to 30 min of regional ischemia and reperfusion. The hearts with persistent VF (n=11) present after 15 min of reperfusion were then randomly assigned into one of the two groups: (1) control hearts (n=6), in which perfusion was continued without intervention; (2) postconditioned hearts (n=5) subjected to 2 min of global ischemia followed by reperfusion. Left ventricular pressures, heart rate, coronary flow, and electrogram were monitored throughout the experiment. Results: Conversion of VF into regular rhythm was observed in all hearts subjected to postconditioning. Regular beating was maintained by all postconditioned hearts during the subsequent reperfusion. None of the hearts in the control group had normal rhythm at the end of the experiment. At the end of reperfusion, the left ventricular developed pressure was lower in beating postconditioned hearts compared to the hearts that did not develop persistent VF. Conclusions: Ischemic postconditioning possesses strong antiarrhythmic effect against persistent reperfusion-induced tachyarrhythmias. Postconditioning may be an interesting, novel adjunct strategy to protect the heart.     

Does your hospital need a robot or a management trainer?

Executives of small hospitals and home health services have heard that this is the Age of Computers, Telecommunications, Robotics, and Gene Engineering, and they wonder if their organizations might benefit from the high technology and advanced management tools employed by big corporations and “leading edge” hospitals. But they are too tired and busy to greatly expand their technical/managerial expertise, especially since there are so many choices among possible innovations, ranging from robotics to management training, each choice demanding different new expertise, and each requiring an investment of time and energy. We helped several health care executives to identify their options for innovation. We offered a scoring scheme to sort out the innovation options (a simple but effective way to decide what innovation would be “right” for their organization), and a simple, “back of the envelope” tutorial on robotics in health care. The principle is to allow the administrators to make a quick evaluation of the paths they might wish to travel. Our point here is that for every “natural-born” innovator, there must be dozens of interested but uncommitted persons who need some gentle, simple help. To the extent that the diffusion of medical systems depends on a mass market, these fence-sitters must receive help and guidance.     

Fresnel membrane prisms: clinical experience

BACKGROUND: There are few published reports on the clinical application of Fresnel membrane prisms in the treatment of diplopia in adults. The authors describe the use of these prisms in patients with fourth and sixth cranial nerve palsies, restrictive motility caused by thyroid-related orbital disease, and convergence insufficiency. METHODS: Of 209 patients who had been treated with Fresnel prisms, 141 were selected. The database included patients from a private practice in Montreal, seen from 1988 to 1996, and patients seen by orthoptists in the ophthalmology department of a children's hospital in Montreal between 1992 and 1996. All the patients had diplopia associated with fourth (48 patients) or sixth (43 patients) cranial nerve palsy, thyroid-related orbitopathy (18 patients) or convergence insufficiency (32 patients). After qualitative and quantitative assessment of the ocular misalignment, a Fresnel prism was selected for power and axis and for appropriate location on the spectacle lens. Ocular dominance and side of paresis or restriction were also considered in the placement of the prism. The patient's response to treatment was documented. RESULTS: The Fresnel prisms were oriented horizontally in 72 patients (51%), vertically in 55 (39%) and obliquely in 14 (10%). They were placed on the spectacle lens before the nondominant eye in 127 cases (90%), either covering the entire lens, or on the upper or lower segment or both. The patients were followed for an average of 15 (range 2 to 96) months. Of the 141 patients 113 (80%) had a successful outcome, with relief of their diplopia. Twenty-seven patients (19%) eventually had the prismatic correction ground into the lens, 70 (50%) chose to wear the Fresnel prism on a permanent basis because incorporation into the lens was not possible or because of cost, and 17 (12%) used the Fresnel prism as a temporary device before or after surgery. Most patients who converted to incorporated prisms did so when the prismatic power became stable, usually after 6 to 8 months. Eight patients (6%) stopped using the prism because of associated side effects, such as blurred vision, persistent diplopia, torsion or optical aberrations. INTERPRETATION: The Fresnel prism is an excellent device in treating diplopia in adult patients. It is a reasonable permanent option when incorporating the prism into the spectacle lens is not possible. A fused blurred image caused by a Fresnel prism placed in front of the nondominant eye is preferable to double but clear images.     

The surgical treatment of patients with colonic cancer complicated by perifocal inflammation of the tissues

In the clinic, at preoperative preparation of the patients with cancer of the colon complicated by perifocal inflammation, the irrigation of a tumour area, using antibacterial preparations, is employed. After laparoscopy, a drainage tube with microirrigator for perfusion of the antibacterial solution is introduced to the region of tumour location. Using the method described, 25 patients were prepared for the operation. Their state improved after 7-8 days. One-stage radical operation was performed in 20 patients. Of them in 17, primary intestinal anastomosis was created.     

Hemorrhagic tumor necrosis during a pilot trial of tumor necrosis factor-alpha and anti-GD3 ganglioside monoclonal antibody in patients with metastatic melanoma

Hemorrhagic tumor necrosis is an inflammatory event that leads to selective destruction of malignant tissues, with both potentially toxic and beneficial consequences. A pilot clinical trial was undertaken combining tumor necrosis factor-alpha (TNF-alpha) with the monoclonal antibody R24 (MoAb R24) against GD3 ganglioside in patients with metastatic melanoma. Patients received MoAb R24 to recruit leukocytes to the tumor followed by low doses of recombinant TNF-alpha to activate leukocytes. Eight patients were treated and seven patients had mild toxicity. One patient with extensive metastatic melanoma developed tumor lysis syndrome within hours after treatment with almost complete necrosis of bulky tumors in multiple visceral sites. To our knowledge, this is the first documented case of hemorrhagic tumor necrosis in a patient with metastatic cancer in multiple visceral sites.