Mitral valve replacement: randomized trial of St. Jude and Medtronic Hall prostheses.

BACKGROUND: This study was designed to better define the merits of the bileaflet and tilting-disc valves. METHODS: We prospectively randomized 156 patients (mean age, 59 years) to receive either the St. Jude (n = 80) or the Medtronic Hall (n = 76) mitral valve prosthesis between September 1986 and December 1997. The two groups were not significantly different with respect to preoperative New York Heart Association class, left ventricular ejection fraction, incidence of mitral stenosis or insufficiency, extent of coronary artery disease, completeness of revascularization, or cross-clamp or bypass time. RESULTS: The operative mortality (11.2% versus 13.1%, St. Jude versus Medtronic Hall, respectively) and late mortality (27% versus 22%, St. Jude versus Medtronic Hall, respectively) were not significantly different. Follow-up was complete in all hospital survivors with a mean of 60.7 months (range, 1 to 133 months). The analysis of 10-year actuarial survival and freedom from valve-related events demonstrated no significant differences between the cohorts. Freedom from reoperation was higher in the St. Jude group (p < 0.01). Comparisons of patient functional status and echocardiographic hemodynamic parameters obtained at the time of follow-up demonstrated no significant differences between the two prostheses. CONCLUSIONS: This study suggests that there is no difference between the St. Jude and Medtronic Hall prostheses with respect to late clinical performance or hemodynamic results and therefore does not support the preferential selection of either prosthesis.

Review of nursing home regulations.

Nursing homes are complex, specialized institutions for a growing segment of the population. Health care professionals should be aware of government regulations that currently influence nursing home practice. The effects of these regulations as well as consumer implications necessary for optimal care of nursing home residents will be addressed.

The stroke patient and assessment of caregiver needs.

Currently, morbidity and mortality rates after stroke are declining as a result of advances in medical care and technology. Despite this decline, the physical, emotional, and psychologic effects of stroke remain devastating. Continuous requirements and long-term commitment with limited resources are a reality for many caregivers. Common problems include role changes, stress, social isolation, and financial burden. A supportive and encouraging atmosphere by the caregiver and an understanding of the emotional and physical challenges that are faced by the person who has had a stroke are essential determinants of a successful rehabilitation.

The role of laparoscopic Nissen fundoplication in gastroesophageal reflux disease.

Gastroesophageal reflux is a highly prevalent condition that usually requires long-term medical therapy. Although symptom management still remains satisfactory for the majority of patients, laparoscopic Nissen fundoplication is proving to be an effective alternative in treating complications of gastroesophageal reflux disease.

Nursing care of patients undergoing thoracoscopic minimally invasive bypass grafting.

Recent efforts in cardiac surgery to decrease cost, length of hospitalization, and morbidity without compromising care or outcomes include a method of treatment of coronary heart disease called minimally invasive coronary artery bypass grafting. This article describes the use of thoracoscopy without sternotomy, cardiopulmonary bypass, or cardioplegic arrest for grafting of the left anterior descending branch of the coronary artery with the left internal mammary artery. Preliminary information supports the concept that thoracoscopic minimally invasive bypass grafting is a less costly and less invasive procedure for patients with disease of the left anterior descending branch of the coronary artery.

Nursing care of the thoracoscopic lung volume reduction patient.

BACKGROUND: Several methods to surgically enhance pulmonary function and improve the quality of life in patients with bullous emphysema are currently being evaluated. One of these methods, lung volume reduction, is performed in patients with bullous emphysema that can no longer be well managed with medical therapy. OBJECTIVES: The focus of this article is to review bullectomy via unilateral thoracoscopy with an endoscopic stapler in the management of end-stage pulmonary emphysema, and to discuss nursing care of these patients. METHODS: An experimental study was used, including review of the literature and analysis of clinical experience using chi-square and t test analyses of pre- and postoperative variables. RESULTS: At 3-month follow-up there were significant improvements in forced expiratory volume in 1 second, forced vital capacity, minute volume ventilation, partial pressure of oxygen, residual volume, and 6-minute walk when pre- and postoperative parameters were compared. Operative mortality was 4%, with the most common complication being prolonged air leak, occurring in 30% of patients studied. CONCLUSIONS: There is now consistent preliminary information to support the concept that lung volume reduction improves pulmonary function and quality of life in a significant percentage of patients.

Current status and future trends of mechanical circulatory support.

This article provides a brief overview of the ventricular assist devices (VADs) available for patients with severe ventricular failure. The history of VAD development and clinical results in the adult and pediatric population are reviewed. Because the VAD role is expanding, nursing implications and a critical analysis of the growing economic concerns regarding their use are discussed.

Infectious complications associated with ventricular assist devices.

Improvements in technology, patient selection, and patient management have led to a wider clinical application of mechanical circulatory support. Critically ill patients often develop multiorgan ischemia and are prone to multiple complications. Despite these advances, infection is a common and sometimes lethal complication of support with ventricular assist devices. This article provides guidelines for the prevention and management of infection in patients who require such support.

Tailoring aortoplasty for repair of fusiform ascending aortic aneurysms.

To evaluate the effectiveness of tailoring aortoplasty used to treat fusiform aneurysms of the ascending aorta, we reviewed the results of operation in 17 patients. Nine patients had tailoring aortoplasty alone, and 8 patients had aortoplasty with Dacron wrap of the ascending aorta. Fourteen of 17 patients were discharged from the hospital, and 12 patients were alive at follow-up between 2 and 120 months. Of two late deaths, neither was due to aneurysmal disease. Actuarial survival at 1 and 10 years was 81% and 63%, respectively. In selected cases, tailoring aortoplasty can achieve long-term results comparable with those of resection and graft replacement of fusiform ascending aortic aneurysms.

Effect of advancing age on cost and outcome of coronary artery bypass grafting.

The clinical and billing records of 250 patients (173 men and 77 women) undergoing isolated coronary artery bypass grafting between 1987 and mid-1990 were retrospectively reviewed to determine charges and clinical results as related to age. Patients were stratified by age into five groups of 50 consecutive patients each: group 1, less than 50 years of age; group 2, 50 to 59 years; group 3, 60 to 69 years; group 4, 70 to 79 years; and group 5, 80 years or older. The groups were compared in regard to perioperative clinical variables, long-term follow-up, and total charges. Group 5 had significantly more postoperative complications than the other four groups (p < 0.05). In addition, length of postoperative hospitalization was significantly longer in group 5 compared with groups 1, 2, and 3 (p < 0.05), and operative mortality in group 5 (20%) was significantly higher than that in the other four groups. The mean total charges for group 5 were $73,399, which was significantly higher than the totals in the other four groups (p < 0.05). Actuarial 3-year survival for the hospital survivors was 87%, 89%, 78%, 82%, and 60% for groups 1, 2, 3, 4, and 5, respectively (p < 0.001). Postoperative performance as measured by the Karnofsky scale was significantly lower in group 5 than in groups 1 and 2 (p < 0.05). These data support the premise that elderly patients undergoing coronary artery bypass grafting have more complications, longer hospitalizations, and higher operative mortality than younger patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac surgery in the octogenarian: nursing implications.

OBJECTIVE: To determine morbidity and mortality rates in octogenarians undergoing cardiac surgical repairs and to compare these results with a similar group of younger patients. DESIGN: Retrospective, two-group. SETTING: Midwestern university medical center. SUBJECTS: Group I consisted of 235 male and female patients who were all less than 80 years of age. Group II consisted of 235 male and female patients who were 80 years of age or older. Both groups underwent similar cardiac surgical procedures. OUTCOME MEASURES: Development of postoperative complications, length of hospitalization, and mortality. RESULTS: When comparing octogenarians with younger patients, octogenarians developed significantly more postoperative complications with higher operative mortality. In addition, octogenarians were hospitalized significantly longer than the younger group. CONCLUSION: These findings suggest that age is a major risk factor influencing outcome after surgery. However, by incorporating nursing interventions with geriatric concepts, those postoperative complications that are common in octogenarians may be more effectively treated and possibly prevented. With sensitive and knowledge-based care, most older patients can anticipate good recovery after cardiac surgery.

Anterior exposure of the thoracic spine.

Spinal operation via an anterior thoracic approach is becoming increasingly common, and the thoracic surgeon is now being called upon to provide exposure for orthopedic and neurosurgical colleagues. We report experience with 126 such patients from 1982 through 1993. There were 61 male and 65 female patients (mean age, 39.0 years; range, 14 to 77 years). Indications were trauma in 45 patients (36%), spinal deformity in 42 (33%), cancer in 15 (12%), disc disease in 12 (10%), and infection in 12 (10%). Operative incisions included 22 (17%) right and 14 (11%) left thoracotomies, 33 (26%) right and 56 (44%) left thoracolumbar approaches, and one (1%) sternotomy. A prior spinal operation had been performed on 31 patients (25%), and 56 (44%) had a subsequent posterior spinal operation. Instrumentation was used in 38 (30%) and bone grafts in all but 6 patients. A neurologic deficit was present in 69 patients (55%) preoperatively and was improved in 67 patients postoperatively. Operative mortality was 3.2% (4 patients) due to myocardial infarction, stroke with pneumonia, adult respiratory distress syndrome, and malignant biliary obstruction. Univariate and multivariate risk analysis were performed. Only the diagnosis of osteomyelitis proved to be a significant (p = 0.0002) indicator of operative mortality, with 3 of 12 such patients dying (25%). These results suggest that anterior spinal exposure via thoracic approach is a major operation with considerable perioperative risk. Patients with osteomyelitis appear to be at increased risk for operative mortality.

Vascular complications from intraaortic balloons: risk analysis.

PURPOSE: The purpose of this study was to assess the incidence of and predictors for vascular complications in patients who required perioperative intraaortic balloon pump (IABP) support. METHODS: Data from 580 patients collected with a retrospective review were statistically analyzed with 25 perioperative parameters, and significant variables were evaluated with multivariate analysis. These data were also statistically compared with data from a 1983 study from our institution. RESULTS: Vascular complications occurred in 72 patients (12.4%). The three aortic perforations were fatal. Ipsilateral leg ischemia occurred in 69 patients. Of these, ischemia was resolved in 82% of patients by IABP removal (21), thrombectomy (21), vascular repair (13), fasciotomy (2), or without intervention (2). Six patients died with the intraaortic balloon in place. Four patients required amputation for ischemia, but all survived. CONCLUSIONS: Vascular complications were not predictive of operative death (p = 0.26). Risk analyses with 25 perioperative parameters revealed that history of peripheral vascular disease, female sex, history of smoking, and postoperative insertion were independent predictors of vascular complications. However, most risk for vascular complications cannot be explained by these factors because of a low R2 value. Compared with the results of our 1983 study, the incidence of IABP-related complications has not changed, but the severity of complications has decreased significantly, and IABP-induced death has decreased significantly.

Inflammatory glia mediate delayed neuronal damage after ischemia in the central nervous system.

Reactive microglia respond within hours to central nervous system ischemic injury as exhibited by increased surface molecules, including the scavenger receptor. It is at least several days after an insult, however, before these activated mononuclear phagocytes reach a peak of secretory activity with the release of neurotoxins. This period of cytotoxin secretion is associated with a delayed neuronal loss seen in tissues neighboring sites of ischemia. Microglia-suppressing drugs reduce tissue production of neurotoxic factors and improve functional outcome after ischemic injury. Immunosuppressive therapy may offer a means to reduce late neuronal damage associated with stroke.

Nursing care of the patient with an intravascular oxygenator.

Conventional therapy in the management of adult respiratory distress syndrome is often associated with an increased mortality rate. Several methods to improve survival in patients with severe respiratory insufficiency are under evaluation. One recently developed method of treatment is an implantable intravascular oxygenator, which provides supplemental gas exchange for failing lungs. This device can provide temporary ventilatory support in patients with acute, potentially reversible respiratory insufficiency. Reduction in ventilator settings such as airway pressure, oxygen concentration, positive end-expiratory pressure and minute volume can be achieved, decreasing the likelihood of oxygen toxicity and barotrauma. Success of the intravascular oxygenator in adult respiratory distress syndrome is dependent in part on critical care staff expertise. Therefore, a thorough understanding of the operation of this device and its role in acute respiratory failure is necessary for optimal care.

The envelope glycoprotein of human immunodeficiency virus type 1 stimulates release of neurotoxins from monocytes.

Mononuclear phagocytes infected with human immunodeficiency virus 1 (HIV-1) produce soluble factors that kill neurons in culture. To define the molecular events that lead to neuron killing, HIV-1 proteins were tested for the ability to trigger release of neurotoxins from human monocytes and lymphocytes. None of the recombinant-derived HIV-1 proteins examined (reverse transcriptase, protease, gag, nef, or gp120) were directly neurotoxic at concentrations from 100 pM to 10 nM. The envelope glycoprotein gp120 did, however, stimulate both isolated human blood monocytes and the monocytoid line THP-1 (but not lymphocytes or the lymphoid cell line H9) to discharge neurotoxic factors. These toxins consisted of heat-stable, protease-resistant molecules (< 500 Da) that copurified with neurotoxins from HIV-1-infected THP-1 cells and were blocked by antagonists to N-methyl-D-aspartate receptors. Release of neurotoxins through gp120 stimulation involved monocytoid CD4 receptors because toxin production could be inhibited either by a monoclonal antibody to the CD4-binding region of gp120 or by soluble CD4 receptors. Alternatively, production of neuron-killing factors could be induced with a peptide from the CD4-binding region of gp120. These data show that the HIV-1 envelope glycoprotein alone can stimulate neurotoxin release by binding to CD4 receptors of mononuclear phagocytes. Such neurotoxic factors may, in turn, contribute to the central nervous system dysfunction associated with HIV-1 by acting on neurons through N-methyl-D-aspartate receptors.

Brain glia release factors with opposing actions upon neuronal survival.

Microglia and astroglia have been thought to govern the survival of neurons after damage to the CNS. To investigate these putative glia-neuron relationships, we examined microglia and astroglia secretion products for effects upon growth of cultured neurons. Activated microglia secrete small neurotoxic factors (< 500 Da), while astroglia constitutively release proteins (> 10 kDa) that promote neuronal growth. Proteins released from astroglia, moreover, attenuate microglial toxicity, suggesting that different glial populations have opposing actions upon neuronal survival. Further study shows that neurotoxins from microglia are heat-stable, protease-resistant molecules with biologic activities blocked by NMDA receptor antagonists. Microglial factors, although toxic for chick ciliary neurons and rat spinal cord neurons, did not reduce numbers of oligodendroglia, astroglia, or Schwann cells in culture. The microglial neurotoxins can be distinguished from cytokines, from free radical intermediates, from the excitatory amino acids glutamate or aspartate, and from the NMDA receptor-mediated toxin quinolinic acid. We propose that secretion products from reactive microglia, but not astroglia, endanger surviving neurons after CNS injury by release of a novel class of neuron-killing molecules.

Intraaortic balloon pumping in patients requiring cardiac operations. Risk analysis and long-term follow-up.

The intraaortic balloon pump is usually the first mechanical device inserted for perioperative cardiac failure; however, little current information is available regarding short- and long-term effectiveness. From January 1983 through November 1990, 6856 adult patients underwent cardiac surgical procedures, 580 of whom (8.5%) had an intraaortic balloon inserted preoperatively (107 patients), intraoperatively (419 patients), or postoperatively (54 patients). There were 374 men and 206 women with a mean age of 63.9 years (range 19 to 88). Operations included 376 coronary artery bypass grafts, 100 mitral valve replacements (with or without bypass grafting), 70 aortic valve replacements (with or without bypass grafting), 15 double valve replacements (with or without bypass grafting), and 32 other procedures. There were 72 (12.4%) complications related to the balloon pump, of which 42 necessitated surgical intervention including thrombectomy (21), vascular repair (13), fasciotomy (2), aortic repair (1), and amputation (4). Operative mortality for patients supported by the balloon pump was 44%. Multivariate stepwise analysis of 27 parameters revealed six independent predictors of mortality: preoperative New York Heart Association class, transthoracic intraaortic balloon insertion (both p < 0.0001), preoperative administration of intravenous nitroglycerin, age, female gender, and preoperative balloon insertion (p < 0.001). Balloon-related complications were not predictive of death. Of the 326 hospital survivors, only 34 were lost to follow-up. There were 75 late deaths, the cause of which was cardiac in 41 (55%), noncardiac in 20 (27%), and unknown in 14 (19%). Actuarial survivals at 1, 5, and 9 years are 51%, 42%, and 33%. Of the 217 hospital survivors still alive and contacted, 81% were in class I (114) or II (60). These data demonstrate (1) operative mortality for patients requiring an intraaortic balloon in the perioperative period remains high, (2) perioperative risk factors can be identified, (3) complications related to the balloon pump do not affect survival, (4) operative survivors can achieve prolonged survival with excellent functional results, and (5) consideration for alternative methods of circulatory support is justified.

Divergent effects of astroglial and microglial secretions on neuron growth and survival.

Brain glia have a secretory capacity which can modulate neuronal function. Astrocytes release proteins which enhance neuronal survival and induce neuronal growth and differentiation. These effects can be blocked by antagonists of voltage-dependent calcium channels and may be partly mimicked by Bay K 8644, a calcium channel agonist. Two of these neurotrophic proteins appear, on the basis of their physical properties and effects on ciliary ganglion neurons, to be ciliary neurotrophic factor and basic fibroblast growth factor. Activated microglia release a heat- and protease-stable neurotoxin of low molecular weight. This neurotoxicity is blocked by NMDA receptor antagonists. Ciliary neurons exposed to the microglial neurotoxin exhibit an abnormal distribution of neurofilament immunoreactivity, which becomes concentrated in a perinuclear region, while the astroglial growth factors induce neurofilament organization into an extensive neuritic network. The astrocyte-released growth factors can counteract the effect of the microglial neurotoxin and lead to unimpaired neural differentiation in the presence of the neurotoxin.

The importance of patient mobility with ventricular assist device support.

Patients bridged to transplantation with ventricular assist devices (VADs) often require prolonged support. To reduce complications associated with bed rest, the authors developed a program to mobilize patients with VADs. Between August 1986 and May 1992, 25 men and 7 women aged 12-65 years (mean: 42.4 years) were bridged for possible transplantation. The 32 patients were supported with either a Novacor (n = 9) or a Thoratec (n = 23) VAD. Thirty-one patients were turned within 2-12 hr of VAD insertion and received range of motion therapy. Twenty-six patients sat in a chair 2-16 days (mean: 5 days) after VAD insertion. Twenty-one patients used a stationary bicycle, and 23 patients were ambulatory 3-57 days (mean: 11 days) after VAD insertion. Two patients were transplanted within 72 hr of device insertion. Twenty-one of the 23 ambulatory patients were successfully transplanted or weaned from the VAD and discharged from the hospital. Two ambulatory patients who were difficult to rehabilitate (ambulatory 22 and 57 days, respectively, after VAD insertion) died before transplantation. In conclusion, VAD patients should be mobilized early because the VAD can improve exercise capability and survival rate.