We studied the mechanism of impairment of gas exchange following sedation with the alpha2 adrenoreceptor agonist, xylazine, in Suffolk cross-bred sheep spontaneously breathing room air. Xylazine caused a significant fall in PaO2 from a mean (pre-xylazine) of 97.9 mm Hg (6.7 mm Hg SEM) to a mean of 38.1 mm Hg (3.2 mm Hg SEM) one minute after injection with a transient increase in PaCO2 from a mean (pre-xylazine) of 32.6 mm Hg (1.9 mm Hg SEM) to a mean of 40.2 mm Hg (3.0 mm Hg SEM). There was no significant fall in mean arterial pressure or in white cell count. There was no significant change in a number of indices of free radical release which included ascorbyl radical, plasma antioxidant potential and alpha-tert-butyl phenyl nitrone (PBN) spin adduct measured simultaneously in both arterial and venous blood. In all sheep given xylazine there was no histological evidence of platelet emboli but lung histopathology showed evidence of pulmonary oedema and intense microvascular congestion with red cells extravasated into alveoli. No such histological changes were seen in the lungs of normal sheep. The impaired gas exchange during sedation with xylazine in sheep is caused, not by an oxidant mediated inflammatory mechanism or by platelet emboli, but by intense alveolar oedema which is probably due to pulmonary venospasm.

Adrenergic alpha-Agonists↗

PubMedDate not supplied

Prediction of right ventricular and posterior wall ST elevation by coronary care nurses: the 12-lead electrocardiograph versus the 18-lead electrocardiograph.

OBJECTIVES: To determine the value of routine versus selective use of the 18-lead electrocardiogram in determining the size of an acute inferior myocardial infarction (MI). DESIGN: Prospective, quasi-experimental, random assignment. SETTING: The coronary care unit (CCU) of a major teaching hospital in South Australia. PATIENTS: Fifty-two patients admitted to the CCU with acute evolving inferior MI. OUTCOME MEASURES: Correlation and comparison of the predictions of the right ventricular (RV) and posterior wall (PW) lead ST elevation with prospectively chosen markers on the 12-lead electrocardiogram--ST elevation in lead III > II and precordial ST depression, and the predictions by coronary care nurses. PROCEDURE: The results of 18-lead electrocardiograms of 52 consecutive patients admitted to the CCU with acute evolving inferior MI were classified according to prospectively chosen criteria. Coronary care nurses were randomly assigned four 12-lead electrocardiograms and asked to "blindly" predict ST elevation in the concurrent RV and PW leads. RESULTS: ST elevation in lead III > II demonstrated a sensitivity and positive predictive accuracy of 86% to 1 mm of ST elevation in the RV leads. ST depression in V1, V2, and V3 similarly demonstrated a 75% sensitivity and 89% positive predictive accuracy to 1 mm of ST elevation in the PW leads. In comparison, coronary care nurses proved to be as accurate in their predictions of additional PW ST elevation (p = 0.73), but were significantly less able to predict RV ST elevation (p = 0.049). These predictions were independent of the level of experience and qualifications. CONCLUSIONS: Discriminating between smaller and larger types of inferior MIs has the potential to alter patient management: Thirty-two percent of patients in the study demonstrated additional ST elevation in both the RV and PW leads. Both of the 12-lead electrocardiogram markers used in this study proved reasonably accurate in predicting additional ST elevation in the leads that normally comprise the 18-lead electrocardiogram. Recognition of these markers has the potential to expedite the need for the additional 18-lead electrocardiogram when rapid assessment of infarction size is required. However, the routine use of the 18-lead electrocardiogram is supported by this study.

Clinical Competence↗

PubMedDate not supplied

A study of unplanned readmissions to a coronary care unit.

OBJECTIVE: To determine the cause and frequency of unplanned readmissions to a coronary care unit (CCU) after initial transfer to a general cardiac unit, but before hospital discharge. DESIGN: Analysis of 1776 admissions to a CCU during a 16-month period. SETTING: The CCU of a major teaching hospital in South Australia. PARTICIPANTS: All patients admitted to the CCU during the 16-month period. OUTCOME MEASURES: CCU readmissions before hospital discharge were categorized as either "planned" or "unplanned." The latter were investigated for determination of casualty and variations in patient characteristics (including age, sex, initial diagnosis, pharmacotherapy, and duration of stay in the CCU). RESULTS: Of the 1776 CCU admissions examined, 44 (2.5% of total) were unplanned readmissions before hospital discharge. Most of these (39 of 44) were related to "reactivation" of acute myocardial ischemia. Patients whose initial diagnosis was acute myocardial infarction or unstable angina pectoris were more likely to require a further unplanned CCU admission (p < 0.05); those with unstable angina pectoris had a second stay in CCU significantly longer than their first (p < 0.05). Six patients were readmitted within 6 hours of cessation of a heparin infusion (4 of the 6 without aspirin administration), and 11 patients had not received antiplatelet therapy after their initial CCU stay. Overall, a disproportionate number of men were readmitted to CCU (p < 0.05). CONCLUSIONS: In the current study, unplanned readmissions to the CCU: (1) were relatively infrequent, (2) were more protracted than initial stays in CCU, (3) may have been prevented in 15 of the 44 cases with more appropriate pharmacotherapy, and (4) involved a disproportionate number of male patients.

Aged↗

PubMedDate not supplied

Personality disorders and coping among anxious older adults.

This study examined the interrelationships among anxiety, personality disorders, and coping strategies in anxious older adults (n = 28; age range = 55-89; mean = 66.0), nonanxious older adults (n = 100, age range = 55-79, mean = 64.6 ), and anxious younger adults (n = 132; age range = 17-30; mean = 20.2). Younger participants were college students and older participants were community-based family members of the students or recruits from local senior centers. Participants completed the Coolidge Axis II Inventory, the Coping Orientations to Problems Experienced scale, and the Brief Symptom Inventory. Results indicated that the prevalence of generalized anxiety states was relatively low and similar in both older and younger groups and dependent on measurement scale and criterion. At least one personality disorder was found in 61% of the older persons group; obsessive-compulsive, schizoid, and avoidant were the most frequently assigned personality disorders. Anxious older adults had elevated rates of dependent and avoidant personality disorder compared with nonanxious older adults. Younger anxious persons were found to have significantly greater personality dysfunction compared with older anxious persons. Finally, coping differences existed between older anxious and older nonanxious adults and between older anxious and younger anxious adults. Implications for diagnosis and treatment of anxiety in older adults were discussed.

Adaptation, Psychological↗

PubMedDate not supplied

Hmong women and postpartum depression.

Evidence of postpartum depression in Western culture has been widely documented in the literature. The conclusion reached by many researchers is that women are vulnerable to depression following childbirth to some extent. It has been suggested that postpartum depression is a culture-bound syndrome that develops because of lack of supportive rites and rituals surrounding childbirth. The present study was undertaken to explore postpartum depression in Hmong women living in the U.S. and the influence of cultural practices on postpartum depression. The results indicate that cultural beliefs and practices help the Hmong women adjust to the postpartum period. Whatever symptoms of depression they reported were related to living in a different culture and different environment, and using a language to which they were not accustomed.

Acculturation↗

PubMedDate not supplied

Prospective trial using Virtual Vision as distraction technique in patients undergoing gastric laboratory procedures.

To determine whether distraction techniques using Virtual Vision, an audiovisual system integrated into a modified pair of glasses, improves tolerance to routine gastric laboratory procedures, a prospective study of 50 patients was done. Patients were allowed to view/hear a travelogue tape during testing. Patients and registered nurses, who performed the procedure, were asked their interpretation of Virtual Vision as a device that improved patient tolerance, impaired the patient's ability to follow directions, or impaired the nurse's ability to perform the procedure. Patients graded the procedure from 1 (unbearable) to 5 (reasonably comfortable) and were asked whether they would use the device for a repeat procedure. For those who had undergone previous procedures, patients were queried regarding their preference for routine testing or Virtual Vision. Improved tolerance to procedures was noted in 82% of the patients as perceived by nurses and patients. Eighteen percent of the nurses and 8% of the patients thought that the auditory insert and glasses impaired the patient's ability to cooperate with the test, whereas 88% and 86%, respectively, thought that Virtual Vision was a valuable distraction technique. Using an ordinal scale for testing tolerance, patients graded their test at a mean of 3.8 (SD 1.25) and 82% expressed a desire to use the system in conjunction with future testing. Twenty-six of 33 patients (79%) who had undergone previous gastric laboratory testing preferred distraction techniques using Virtual Vision to conventional testing. Distraction techniques using a system such as Virtual Vision have the potential to improve patient tolerance to routine gastric laboratory studies.

Adolescent↗

PubMedDate not supplied

An assessment of cardiac output by thermodilution in infants and children following cardiac surgery.

A 4 F thermodilution catheter for measuring cardiac output was evaluated for accuracy and linearity in the laboratory and by comparison with the dye dilution method in infants and children following cardiac surgery. When 2 ml of 0 degrees C injectate were used, the correlation of computer determined flows to calibrated pump flows, over a range encountered clinically, was r = 0.998. The means of triplicate determinations by both the thermal and dye methods were compared in 8 of 25 patients and the comparison found to be favorable (r = 0.976). The complications of thermodilution catheter placement are described and related to the need for post-surgical chest x-ray and thermodilution recordings. The simplicity of the thermodilution technique and other advantages over the dye method in children, such as repeatability, and ease of calibration are discussed in relation to the increased flexibility in management which accrues.

Cardiac Catheterization↗

PubMedDate not supplied

Caring for patients with acute myocardial ischaemia: the perhexiline maleate experience.

Perhexiline Maleate (Px) is a potent, oxygen-sparing agent used in the management of patients with acute myocardial ischaemia that is resistant to conventional pharmacological therapy. The critical care nurse plays an integral role in (1) maximizing the therapeutic benefits of Px and (2) ensuring that the patient reaches the point of correctional intervention with the minimum of ischaemic damage.

Critical Care↗

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Early detection and management of right ventricular infarction: the role of the critical care nurse.

Patients with acute inferior myocardial infarction (IMI), complicated by a more extensive right ventricular infarction (RVI), have an increased risk of both complications and mortality. The critical care nurse plays an important role in 1) the early detection of RVI and 2) the management of the common hemodynamic and conduction disturbances that can typically arise.

Critical Care↗

PubMedDate not supplied

Managing patients with acute myocardial ischemia and reperfusion injury with N-acetylcysteine.

Previously administered in cases of acetaminophen toxicity, N-Acetylcysteine (NAC) is now also being used in the management of acute myocardial ischemia and reperfusion injury. NAC potentiates the beneficial effects of nitrates such as nitroglycerin and reduces oxidative stress on the heart. The critical care nurse plays an important role in optimizing the therapeutic benefits of NAC and minimizing its potential harmful effects.

Acetylcysteine↗

PubMedDate not supplied

The role of ST-segment monitoring in assessment of acute myocardial infarction.

Continuous ST-segment analysis is an accurate and noninvasive tool for monitoring coronary artery patency in patients with acute myocardial infarction. This type of monitoring also is easy to use and cost-effective. The critical care nurse plays a pivotal role in initiating ST-segment monitoring, promptly detecting ST-segment changes, and rapidly intervening to achieve myocardial reperfusion.

Aged↗

PubMedDate not supplied

A family systems approach to home dialysis.

Dramatic increases in the cost of the end stage renal disease program are producing an emphasis on home dialysis with the patient and his family carrying the responsibility for this treatment. This requires an adjustment of the family's emotional system and role assignment to sustain members through the continued stress of chronic catastrophic illness. We are suggesting a model of intervention in which family members are encouraged to recognize stress caused by one member's illness and to make necessary changes in the family functioning.

Adult↗