EFFECT OF A SUB-ANAESTHETIC CONCENTRATION OF HALOTHANE ON THE VENTILATORY RESPONSE TO SUSTAINED HYPOXIA IN HEALTHY HUMANS

We selected nine normal subjects (8M, 1F; aged 25–43 yr)with brisk hypoxic ventilatory responses, and studied theirventilatory response to sustained isocapnic hypoxia     

Prophylactic single-dose metronidazole before abdominal hysterectomy

Summary. The vagina is a common source of non-sporing anaerobic bacteria which may be the cause of postoperative infection after hysterectomy. A single vaginal pessary containing 1 g of metronidazole inserted the night before abdominal hysterectomy reduced the mean duration of postoperative pyrexia from 15·4 to 8·3 h ( P <0·05).     

The Generation of Specific Cytotoxic Responses by Human Lymphocytes Requires Antigen and Activities Provided by a Lymphokine Supernatant-

The requirements for the generation of specific cytotoxic responses by human lymphocytes have been investigated using as a model system the response to the ultraviolet light-killed mouse tumour P815. These requirements are antigen (P815_uv) and activities provided by a human lymphokine (LK) supernatant. Cells that give rise to non-specific cytotoxicity can be separated on discontinuous Percoll density gradients after a 3-day incubation of peripheral blood leucocytes with the lymphokine supernatant. Cells from which specific cytotoxic responses can subsequently be generated in the presence of P815_uv and LK sediment at a higher density.     

The Psychological Impact of Implantable Cardioverter-Defibrillator Recalls and the Durable Positive Effects of Counseling

Background: It is known that patients with lifesaving devices such as implantable cardioverter-defibrillators (ICDs) may be alarmed and worried by recalls or alerts related to their ICDs.
Objectives: This study aimed to determine whether counseling has any short- or long-term benefits, and to look for characteristics that identify those most worried and those most in need of counseling.
Methods: Among 100 patients with recall or alert ICDs, 14 were pacer dependent; 50 had ICDs for 1° prevention and 22 were women. Patients completed a survey indicating how worried they were on learning of the recall or alert (0–10 scale). After counseling and advice in accordance with manufacturer guidelines, patients were asked to indicate their level of worry, and were again asked after 6 months.
Results: For all patients, the "worry level" at the initial interview was 5.0 ± 3.7, falling to 2.2 ± 3.0 after counseling (P < 0.001) and 1.4 ± 2.3 after 6 months (P < 0.001 vs both earlier levels). There were no significant differences between those implanted for 1° versus 2° prevention or for pacer dependency. Women were initially more worried than men, but not for the long term. The 49 patients whose ICDs could be managed by reprogramming or software fix had significant reduction in worry after counseling and at 6 months compared to others. The 18 patients recommended for operative intervention remained more concerned after counseling (3.5 ± 3.3 vs 1.9 ± 2.9, P = 0.043).
Conclusions: Patients' concerns resulting from ICD recalls or alerts can be reduced by appropriate counseling. Those patients whose ICDs could be reprogrammed to safer parameters had the most reduction in worry levels.     

Value of Pre-Hospital Discharge Defibrillation Testing in Recipients of Implanted Cardioverter Defibrillators

Opinions vary regarding the need to perform defibrillation testing prior to hospital discharge in recipients of state-of-the-art cardioverter defibrillators (ICDs). Our protocol is to perform predischarge ICD testing 1 day after implant. This report includes 682 consecutive implants. Adverse observations at testing were grouped into (1) risk of defibrillation failure, (2) surgical complications, (3) sensing/pacing issues or narrow defibrillation margin warranting closer follow-up, or (4) findings correctable by device reprogramming. Among the 682 patients, 63% had single-chamber and 37% dual-chamber or biventricular ICDs. In 48 patients (7%) there were 69 concerns and/or interventions, with overlaps among the four categories, including one failure to defibrillate (0.15%), and six other patients at risk. Surgical complications included 11 hematomas (1.6%), and six lead dysfunctions. Closer follow-up was indicated in 19 patients (2.7%), for high pacing thresholds in seven, sensing issues in seven, and <10 J defibrillation margin in five. Device reprogramming was needed in 31 patients (4.5%), for tachycardia detection and therapy settings in 12, and for pacing/sensing functions in 22 patients. In eight patients ventricular fibrillation could not be induced. There was no morbidity or mortality due to testing. The state-of-the-art ICDs delivering biphasic shocks are remarkably reliable. The routine pre-hospital discharge defibrillation testing of such ICDs may be optional and left to the physicians' discretion.     

Performance of Implantable Cardiac Rhythm Management Devices

Our data represent use, follow-up, and management decisions from seven independently functioning centers and most importantly, actuarial survival of ICRMDs that have been implanted for sufficient time period to allow assessment of time versus failure. General patterns of possible target durations for adequate performance for present or future generations of similar clinical devices may be suggested by the data that we have presented. However, it would be inappropriate to conclude from these data that any presently implanted ICRMD would have a particular functional reliability. These data, furthermore, only summarized device hardware performance and cannot and must not be used to determine either short-term or long-term individual patient status, management, or outcome.     

Design and Objectives of the Evaluation of Oral Xemilofiban in Controlling Thrombotic Events (EXCITE) Study

Clinical trials have demonstrated the efficacy of glycoprotein (GP) IIb/IIIa antagonists in preventing the thrombotic end points of death, myocardial infarction, and urgent revascularization when they are administered at the time of percutaneous coronary revascularization (PTCR). It has been postulated that prolongation of receptor blockade beyond acute intervention would extend the clinical benefit of these agents. The Evaluation of Oral Xemilofiban in Controlling Thrombotic Events (EXCITE) study was a multicenter, international, randomized placebo-controlled trial of the oral GP IIb/IIIa antagonist Xemilofiban administered prior to and after PTCR. The study was designed to assess the efficacy and safety of continuing oral xemilofiban for 6 months to prevent these primary thrombotic end points. More than 7,200 patients were randomized in 29 countries to receive placebo or one of two doses of xemilofiban. Stenting was performed at the discretion of the operator. All patients received aspirin and periprocedural heparin; all stented patients received continuous xemilofiban, or ticlopidine for 2–4 weeks followed by xemilofiban-placebo. Most patients were also evaluated 1 month after conclusion of the study drug treatment. Clinical data from up to 6 months of drug treatment and 1 month posttreatment were used to evaluate the acute and long-term efficacy and safety of xemilofiban. Secondary end points included the need for any revascularization, repeat hospitalization for unstable angina, and nonhemorrhagic stroke. The cumulative incidence of bleeding events and effects of xemilofiban in stented and nonstented patients were evaluated. The efficacy of continuing xemilofiban and aspirin therapy as the sole antithrombotic medications following stent deployment was assessed against a ticlopidine and aspirin control group. The incremental clinical benefit of long-term receptor blockade over acute receptor antagonism was evaluated.