The risk of myocardial ischemia in patients receiving desflurane versus sufentanil anesthesia for coronary artery bypass graft surgery. The S.P.I. Research Group.

Desflurane, a coronary vasodilator, may induce myocardial ischemia in patients with coronary artery disease. To determine whether desflurane is safe to administer to the at-risk patient population (with known coronary artery disease), we compared the incidence and characteristics of perioperative myocardial ischemia in 200 patients undergoing coronary artery bypass graft (CABG) surgery randomly assigned to receive desflurane (thiopental adjuvant) versus sufentanil anesthesia. Under conditions of hemodynamic control, perioperative ischemia was assessed using continuous echocardiography (precordial: during induction; transesophageal: during surgery) and Holter electrocardiography (ECG); hemodynamics (including pulmonary artery pressure) were measured continuously. Hemodynamic results: During induction, no significant changes in hemodynamics occurred in the sufentanil group, while in the desflurane group, heart rate, systemic and pulmonary arterial pressure increased and stroke volume decreased significantly. During the intraoperative period, the incidence of hemodynamic variations was low in both anesthetic groups; however, the prebypass incidence of tachycardia (greater than 120% of preoperative baseline heart rate) was greater in the desflurane group (4 +/- 7% of total time monitored) than in the sufentanil group (1 +/- 6%) (P = 0.0003). Similarly, the incidence of prebypass hypotension (less than 80% of preoperative baseline systolic arterial blood pressure) was greater in the desflurane group (21 +/- 14%) than in the sufentanil group (15 +/- 16%) (P = 0.01). ECG results: Preoperatively, 15% (28/191) of patients developed ECG ischemia, with no difference between patients who received desflurane, 13% (12/96) or sufentanil, 16% (16/95) (P = 0.6). During anesthetic induction, 9% (9/99) of patients who received desflurane developed ECG ischemia, compared with 0% (0/98) who received sufentanil (P = 0.007). During the prebypass period, 5% (10/197) of patients developed ECG ischemia, with no difference between patients who received desflurane, 7% (7/99) or sufentanil, 3% (3/98) (P = 0.3). Postbypass, 12% (24/194) of patients developed ECG ischemic changes, with no difference between patients who received desflurane, 13% (13/97) or sufentanil, 11% (11/96) (P = 0.9). Echocardiographic results: The incidence of precordial echocardiographic ischemia during anesthetic induction was 13% (5/39) in the desflurane group versus 0% (0/29) in the sufentanil group (P = 0.1). Moderate to severe transesophageal echocardiographic (TEE) ischemic episodes occurred in 12% (21/175) of patients during prebypass, with no significant difference between the desflurane group, 16% (15/91) and the sufentanil group, 7% (6/84) (P = 0.09). TEE ischemic episodes occurred in 27% (49/178) of patients during the postbypass period, with no difference between the desflurane, 29% (27/92) and sufentanil, 25% (22/86) groups (P = 0.7).(ABSTRACT TRUNCATED AT 400 WORDS)     

Determination of IgG subclass antibodies to Pseudomonas aeruginosa outer membrane proteins in cystic fibrosis lung infection using immunoblotting and enzyme-linked immunosorbent assay

IgG subclass antibodies to Pseudomonas aemginosa outer membrane proteins (OMP) were investigated in serum from cystic fibrosis (CF) patients by immunoblotting and enzyme-linked immunosorbent assay (ELISA). Fifteen patients (eight in good and seven in poor clinical condition) have been followed for an average of 13 years with multiple serum samples covering the preinfection, and early and late stages of chronic infection. Laser-scanning densitometry of photographs taken from immunoblots was used to quantify antibody level and compare with ELISA titres. The earliest anti-OMP antibodies to appear were of the IgG1 subclass. There was no significant difference in IgG subclass antibody levels to OMPs between patients in relatively good and poor clinical condition. Data presented indicate a high positive correlation among measurements of IgG subclass antibodies to P. aeruginosa OMPs using ELISA and immunoblotting.     

Psychobiology and psychiatric nursing: a philosophical matrix.

Over the past several years, conceptualizations of the mind have been challenged by a knowledge explosion in the psychobiological sciences. Such new knowledge continues to fuel a paradigm shift in psychiatry away from traditional psychodynamic models of the mind and toward ones balanced with a psychobiological dimension. The combination of psychodynamic and psychobiological fields of knowledge offers an opportunity for a holistic perspective on the human experience. Psychiatric nursing faces the challenge of integrating this new knowledge for the enrichment of its practice. To accomplish this complex task, issues need to be addressed in many areas critical to psychiatric nursing. Three areas are discussed in this article and include philosophy, communication of philosophy, and testing of philosophy. This article concludes with a discussion of some potential mechanisms to deal with the tensions generated by a paradigm shift in psychiatric nursing.     

Molecular targeting of Alzheimer's amyloid plaques for contrast-enhanced magnetic resonance imaging

Smart molecular probes for both diagnostic and therapeutic purposes are expected to provide significant advances in clinical medicine and biomedical research. We describe such a probe that targets beta-amyloid plaques of Alzheimer's disease and is detectable by magnetic resonance imaging (MRI) because of contrast imparted by gadolinium labeling. Three properties essential for contrast enhancement of beta-amyloid plaques on MRI exist in this smart molecular probe, putrescine-gadolinium-amyloid-beta peptide: (1) transport across the blood-brain barrier following intravenous injection conferred by the polyamine moiety, (2) binding to plaques with molecular specificity by putrescine-amyloid-beta, and (3) magnetic resonance imaging contrast by gadolinium. MRI was performed on ex vivo tissue specimens at 7 T at a spatial resolution approximating plaque size (62.5 microm(3)), in order to prove the concept that the probe, when administered intravenously, can selectively enhance plaques. The plaque-to-background tissue contrast-to-noise ratio, which was precisely correlated with histologically stained plaques, was enhanced more than nine-fold in regions of cortex and hippocampus following intravenous administration of this probe in AD transgenic mice. Continuing engineering efforts to improve spatial resolution are underway in MRI, which may enable in vivo imaging at the resolution of individual plaques with this or similar contrast probes. This could enable early diagnosis and also provide a direct measure of the efficacy of anti-amyloid therapies currently being developed.     

Antidepressant dosing and switching guidelines: focus on nefazodone

Dosing strategies form a fulcrum between patient-related and provider-related dimensions of treatment. The former focus on perceptions of efficacy and safety and adherence to the regimen, whereas the latter focus on symptom identification and appropriate drug selection. Appropriate dosing strategies may modulate adverse effects, allowing the patient to move more comfortably toward an efficacious response. Dosing also is an important dimension in switching between 2 antidepressants when the efficacy of the first agent is suboptimal. Nefazodone is effective for the management of acute, severe, and chronic major depression and relapse prevention. Response rates with nefazodone are comparable to those of imipramine and most SSRIs. In clinical trials, the efficacy of nefazodone was most clearly established at doses between 300 and 600 mg/day. At this dose range, discontinuations because of adverse events are low.     

Bioprosthetic endocarditis due to Cryptococcus neoformans

Fungal prosthetic endocarditis continues to be a lethal complication of cardiac valve replacement. We describe a patient with culture-proved Cryptococcal endocarditis and myocarditis whose non-regurgitant xenograft aortic prosthesis was successfully replaced urgently upon the occurrence of new 1st degree A-V block in the third postoperative week. Operative intervention, including vigorous debridement of the aortic root, is effective in postoperative prosthetic fungal infections involving the myocardium. The patient described herein is now infection-free, with a non-regurgitant valve, one and one-half years following operation.     

Nutritional support in cardiac cachexia.

A nutritional survey of 350 hospital patients reveals 50 with cardiac disease who had clinically significant protein-calorie malnutrition. Assessment criteria of malnutrition (per cent normal) included triceps skin fold (52 per cent), arm muscle circumference (88 per cent), and impaired delayed hypersensitivity skin testing (i.e., deficiency in cell-mediated immunity), the latter frequently observed in patients with concurrent weight loss. The functional category of cardiac status was not precise in predictin the morbidity and mortality of 14 patients undergoing cardiac valvuloplasty. By contrast, a nutritional/metabolic profile using weight loss, triceps skin fold (35 per cent), arm muscle circumference (27 per cent), and cell-mediated immunity (29 per cent) did identify high-risk patients who could be expected to benefit by concurrent nutritional support (4/4). Further studies are indicated to determine if nutritional support for cardiac cachexia can reduce the levels of morbidity and mortality during mitral and tricuspid valve surgery.     

Effects of light therapy on sleep, mood, and temperature in women with nonseasonal major depression

Research has supported the applicability and efficacy of light therapy in the treatment of nonseasonal depression. The investigators examined the effects of light therapy on sleep, core temperature, depressed mood, and perception of fatigue and energy in a sample of pre-menopausal and post-menopausal women diagnosed with nonseasonal, nonbipolar depression. Women were randomly assigned to either light therapy (n = 16) or placebo (n = 13) for a 28-day period. Pre and post measures of sleep and core temperature were collected. In addition, measures of depressed mood, fatigue, and energy were collected throughout the study period. Significant changes in depression and energy were found in the treatment group, but not in the placebo group. There was a significant reduction in the temperature mesor and less wake time during the first third of the sleep period in the treatment group but not in the placebo group. Light therapy yielded significant improvement in depression when compared with placebo intervention and core temperature mesor returned to normal. There was no significant phase shift, perhaps due in part to the absence of any baseline circadian phase disturbances. Relationships between temperature, sleep, depressed mood, fatigue, and energy variables offer potential directions for future research and clinical intervention.     

Owls, larks and the significance of morningness/eveningness rhythm propensity in psychiatric-mental health nursing

In the last decade there has been an upsurge in the research focusing on the interplay between the human circadian timing system and behavioral patterns in health and illness. Of particular interest in this area of inquiry is the overlay of what has been termed chronotype. What this refers to is the propensity of biological rhythms to express themselves in certain patterns of behavior. Commonly, these patterns have received names such as owl (evening chronotype) or lark (morning chronotype). Many people are neither a strong morning nor evening chronotype. If illness represents a change in the way a person's body functions within a given environment, then it is reasonable to believe that an "owl's" symptom presentation may vary significantly from the patterns of a "lark" who becomes ill. Recognizing that psychiatric nurses at both the generalist and the advanced practice levels have a strong interest in patterns of behavior, it stands to reason that using a lens that incorporates notions of the body's clock becomes essential. The interplay between the body's timing system and the thousands of other psychobiological rhythmic functions occurring everyday and within every human being is referred to as chronobiology. This article provides a primer for psychiatric nurses on issues of chronobiology related to morningness and eveningness rhythm propensity.