Weaning from long-term mechanical ventilation.

As many as 5% of patients who need mechanical ventilation will require prolonged mechanical ventilation (PMV). The cost of their care and its associated morbidity is alarming; however, good outcomes can be achieved when their care is specialized and delivered in a programmatic manner. In this article, we review some of the common and potentially reversible reasons why patients fail successfully liberation from mechanical ventilation. We examine the outcomes of patients requiring PMV and present evidence that supports the development of specialized units where patients can be cohorted and may produce better outcomes than would be likely if these patients remained in the ICU.

Circulatory hypokinesis and functional electric stimulation during standing in persons with spinal cord injury.

OBJECTIVE: To evaluate the effects of functional electric stimulation (FES) of lower limb muscles during 30 minutes of upright standing on the central and peripheral hemodynamic response in persons with spinal cord injury (SCI). DESIGN: A repeated-measure design. Subjects were used as their own control and underwent 2 testing protocols of FES-augmented standing (active standing) and non-FES standing (passive standing). SETTING: Rehabilitation hospital. PARTICIPANTS: Fourteen individuals with SCI (7 with tetraplegia, 7 with paraplegia). INTERVENTIONS: During active standing, FES was administered to 4 muscle groups of each leg in an overlapping fashion to produce a pumping mechanism during standing. During passive standing, subjects stood for 30 minutes using a standing frame with no FES intervention. MAIN OUTCOME MEASURES: Central hemodynamic responses of stroke volume, cardiac output, heart rate, arterial blood pressure, total peripheral resistance (TPR), and rate pressure product (RPP) were evaluated by impedance cardiography. All measurements were performed during supine and sitting positions before and after standing, and during 30 minutes of upright standing. RESULTS: Comparisons between the groups with paraplegia and tetraplegia showed a significant increase in heart rate in the paraplegics after 30 minutes of active standing. During active standing, paraplegics' heart rate increased by 18.2% (p = .015); during passive standing, it increased by 6% (p = .041). TPR in the tetraplegics significantly (p = .003) increased by 54% when compared with the paraplegics during passive standing. Overall, the tetraplegic group had a significantly lower systolic blood pressure (p = .013) and mean arterial pressure (p = .048) than the paraplegics during passive standing. These differences were not detected during active standing. When data were pooled from both groups and the overall groups response to active and passive standing were compared, the results showed that cardiac output, stroke volume, and blood pressure significantly decreased (p < .05) during 30 minutes of passive standing, whereas TPR significantly increased (p < .05). All of the hemodynamic variables were maintained during 30 minutes of active standing, and there were increases in RPP and heart rate after 30 minutes of active standing. CONCLUSION: FES of the lower extremity could be used by persons with SCI as an adjunct during standing to prevent orthostatic hypotension and circulatory hypokinesis. This effect may be more beneficial to those with tetraplegia who have a compromised autonomic nervous system and may not be able to adjust their hemodynamics to the change in position.

Quality of Life Evaluation and Survival Study: a 3-yr prospective multinational study on patients with chronic respiratory failure.

Therapy of patients with chronic respiratory failure is mainly directed at minimizing symptoms in order to improve, or at least to prevent a deterioration of, patients' well-being. Under such circumstances, the perceived effect of therapies on patients' well-being and daily life represents the most important subjective outcome of treatment. Therefore, there is a need to provide a global estimate of health in patients on long term oxygen therapy or overnight home mechanical ventilation. The Maugeri Foundation Respiratory Failure Questionnaire (MRF28) is the first health status ("quality of life") questionnaire specifically developed for use in CRF and its items were selected to be applicable to patients with both obstructive and restrictive diseases. The Quality of Life Evaluation and Survival Study (QuESS) is a multinational study with the aim of re-evaluating the natural history of chronic respiratory failure in about 300 patients. To the authors knowledge, the Quality of Life Evaluation and Survival Study is the first study to evaluate the natural history of chronic respiratory failure in such a large number of subjects and with a complete set of data. In fact, both pathophysiologic and health status assessments will be made. Moreover, by collecting data on mortality, disease exacerbations and hospitalization, it will also be possible to verify the predictive ability of health status versus pathophysiology in terms of mortality and healthcare utilization.

Functional status and survival following pulmonary rehabilitation.

BACKGROUND: Functional exercise capacity has been shown to be a strong predictor of survival following pulmonary rehabilitation. This study evaluated whether questionnaire-rated functional status is also predictive of survival. PATIENTS AND METHODS: Following pulmonary rehabilitation, patients with advanced chronic lung disease were evaluated for survival, 6-min walk distance, and questionnaire-rated functional status. The latter was measured using the pulmonary functional status scale, which has subscores of functional activities, psychological status, and dyspnea. Information on survival was available on 149 patients. RESULTS: The mean age was 69 years, and 45% of patients were male. Eighty-nine percent had a diagnosis of COPD, and their FEV(1) was 37+/-18% of predicted. Ninety-one (61%) were married. The 3-year survival for the group was 85%. Age, gender, body mass index, and primary diagnosis were not related to survival. Variables strongly associated with increased survival following pulmonary rehabilitation included a higher postrehabilitation Functional Activities score, a longer postrehabilitation 6-min walk distance, and being married (vs widowed, single, or divorced). Disease severity variables associated with survival included an initial referral to outpatient pulmonary rehabilitation, no supplemental oxygen requirement, and a higher percent-predicted FEV(1). CONCLUSION: Indicators of functional status are strong predictors of survival in patients with advanced lung disease.

Long-term benefits of short-stay inpatient pulmonary rehabilitation in severe chronic obstructive pulmonary disease.

The beneficial effects of pulmonary rehabilitation programmes on the overall quality of life in patients with chronic obstructive pulmonary disease (COPD) has been well documented. However, there has been a paucity of studies demonstrating the long-term benefits of short-stay inpatient pulmonary rehabilitation (SSIPR) programmes in patients with severe COPD (forced expiratory volume in one second (FEV1) < 40% of predicted). The authors have previously reported that their multidisciplinary SSIPR programme improved outcome measurements immediately post-rehabilitation in 38 patients with severe COPD. The purpose of this study was to evaluate the long-term (1-yr follow-up) benefits of SSIPR in these patients. The outcome measurements used were: timed 12-min walking distance, Borg dyspnoea scale, annual days of acute care hospitalization, and Pulmonary Functional Status Scale. All outcome measurements were significantly improved at 1 yr post-SSIPR as compared to pre-SSIPR values. The 12-min walking distance was significantly improved in patients 1 yr post-SSIPR (251 m) as compared to either pre-SSIPR (133 m, p < 0.0001) or immediately post-SSIPR (224 m, p < 0.01). The number of annual days of acute care hospitalization was reduced from 15.4 pre-SSIPR to 3.8 (p < 0.0001) 1 yr post-SSIPR. The Borg dyspnoea scale measurement showed improvement, both at rest and after 12 min walking at 1 yr post-SSIPR. Also, the Pulmonary Functional Status Scale analysis showed significant (p < 0.001) sustained improvement at 1 yr post-SSIPR as compared to pre-SSIPR. In conclusion, it has been demonstrated that long-term sustained outcome benefits can be achieved from a comprehensive short-stay inpatient pulmonary rehabilitation programme for patients with severe chronic obstructive pulmonary disease.

Venous hemodynamics of the lower extremities in response to electrical stimulation.

OBJECTIVE: To evaluate the calf muscle pump function using an air plethysmograph (APG) applied to the lower leg of subjects during three different tiptoe exercises. DESIGN: A controlled trial design was selected to compare the hemodynamic effects of three exercise conditions on a group of able-bodied, healthy patients. SETTING: Testing was performed in an outpatient clinic at a rehabilitation hospital. SUBJECTS: Patient groups were selected from a convenience sample of 10 healthy volunteers with normal venous capacitance and no reflux, determined through impedance pleythysmography before the study. INTERVENTIONS: Three exercise conditions undertaken by each subject consisted of loaded and unloaded lower leg muscle contractions produced by (1) voluntary contraction (VOL), (2) electrical stimulation of the gastocnemius-soleus and tibialis anterior muscles (ES), and (3) combined ES and VOL (ES/VOL). MAIN OUTCOME MEASURE: Hemodynamic measurements of venous filling index upon standing from the supine (VFI), ejection fraction (EF), ejection volume (EV), residual volume (RV), and residual volume fraction (RVF) were recorded after each protocol. These results were used to compare the lower leg hemodynamic effects of the treatments. RESULTS: Combined ES/VOL single tiptoe exercise produced the highest EV (97.8mL), followed by VOL (80.6mL) and ES (51.7mL) (p < .0008). The EF was also highest for combined ES/VOL (73.1%), followed by VOL (64.5%) and ES (37.8%) (p < .0001). Ten tiptoe ES exercises produced the highest RV (96.2mL), followed by ES/VOL (44.7mL) and VOL (28.2mL) (p < .0001). RVF was also highest in the ES group (71%), followed by ES/VOL (33.4%) and VOL (22.8%) (p < .0001). CONCLUSION: Periodic single ES-induced calf muscle contractions produced significant muscle pump function and could be used to improve venous blood flow and reduce stasis in the lower leg. Continuous ES-induced contractions, on the other hand, could improve lower leg peripheral perfusion while eliciting the physiologic venous muscle pump. Higher RV and RVF after 10 ES-induced contractions in this sample of healthy subjects with normal VFI may be caused by an increase in arterial blood perfusion after repeated ES-induced contractions.

COPD and other diseases in chronically ventilated patients in a prolonged respiratory care unit: a retrospective 20-year survival study.

OBJECTIVES: To evaluate the long-term prognosis of ventilator-dependent patients. DESIGN: Retrospective study. SETTING: A prolonged respiratory care unit (PRCU). The PRCU provides comprehensive medical, nursing, and respiratory care to tracheostomized, ventilator-dependent adult patients who had failed all attempts at weaning. Because of their medical complexity, these patients could not be discharged to a lower level of care. PATIENTS: Of the 293 patients admitted to the PRCU over a 20-year period beginning January 1, 1977, 145 had respiratory failure from COPD, 22 from spinal cord disease or trauma, 34 from primary CNS disease, 50 from primary neuromuscular disease, and 16 from chest wall disease. Twenty-six patients were not classifiable into the above categories. MEASUREMENTS: Demographics, diagnoses, and survival data were reviewed. The survival of patients with COPD was compared with the other diagnosis categories using the Cox proportional hazards model. RESULTS: The median survival for the entire group was 9 months; younger age and female gender were both predictive of longer survival (both, p < 0.001). The median survival of those with COPD (5 months) was significantly shorter than that of patients with spinal cord disease (47 months), neuromuscular disease (17 months), and chest wall disease (27 months) (all, p < 0.01). These differences in survival were present even with inclusion of gender and age in the model as covariates. The survival of patients with CNS disease was not significantly different from survival of patients with COPD. CONCLUSION: Chronically ventilated patients with respiratory failure from COPD have a significantly worse prognosis than patients with respiratory failure from other causes.

A regional weaning center for patients requiring mechanical ventilation: an 18-month experience.

This report reviews the outcomes of patients on mechanical ventilation admitted to a new regional weaning center. We reviewed the records of 47 patients admitted to the weaning center over an 18-month period. All patients had a tracheostomy, were ventilator dependent, and considered difficult to wean by their referring physician. The mean days of ventilator dependence prior to transfer to our facility was 86 days, with a range of 21 to 332 days. Patients were admitted to a 12-bed weaning unit at our chronic disease and rehabilitation hospital and assessed by a multi-disciplinary team of physicians, nurses, and therapists. Thirty patients were successfully weaned from prolonged mechanical ventilation and subsequently discharged from our unit. These data indicate that the majority of difficult to wean patients admitted to our regional weaning center were successfully liberated from prolonged mechanical ventilation.

Short-stay comprehensive inpatient pulmonary rehabilitation for advanced chronic obstructive pulmonary disease.

OBJECTIVE: To evaluate the effectiveness of short-term, comprehensive inpatient pulmonary rehabilitation in severe chronic obstructive pulmonary disease (COPD). DESIGN: Retrospective analysis of several outcome measures. SETTING: Inpatient pulmonary rehabilitation unit. PARTICIPANTS: Thirty-eight consecutive adult patients with advanced COPD referred to our inpatient pulmonary rehabilitation program between January 1 and December 31, 1994. All but one were referred from acute care hospitals. The mean forced expiratory volume in 1 second (FEV1) was .69L; 79% required supplemental oxygen. MAIN OUTCOME MEASURES: (1) Discharge status; (2) timed walk, with measurements of distance and exertional dyspnea; and (3) functional status. RESULTS: All patients were able to be discharged home after a mean length of stay of 9.9 days. The 12-minute walk distance increased by 66%, from 416 +/- 282 feet to 690 +/- 337 feet (p < .001). Dyspnea during the walk testing also improved: the resting score decreased from 2.87 to .97, the 6-minute score from 7.84 to 3.05, and postwalk score from 8.53 to 3.51 (all p < .001). All patients showed improvement in the Pulmonary Function Status Scale (PFSS), with the functional activities subsection increasing by 39%, the dyspnea score by 65%, and psychosocial score by 35% (all p < .001). CONCLUSION: Short-term improvement in multiple areas can be accomplished with comprehensive pulmonary rehabilitation of short duration. This is particularly relevant to the current health care environment that dictates shorter in-hospital lengths of stay.

Severe hypothermia in the elderly.

Hypothermia is not an uncommon clinical problem in the geriatric population. Several factors place elderly individuals at risk, including their reduced ability to sense and react to cold and their underlying medical conditions and medications. Successful detection and treatment of these patients involve an awareness of these risk factors and the characteristic physiology of the elderly, as well as an appreciation of the often controversial aspects of hypothermia management. Elderly victims of severe hypothermia have a particularly grave prognosis. We present one of the oldest reported survivors of severe hypothermia, and discuss some unique aspects of his presentation.

Management of the severely anemic patient who refuses transfusion: lessons learned during the care of a Jehovah's Witness.

OBJECTIVE: To present the case of a Jehovah's Witness with severe anemia and to review the religious philosophy of such patients, the ethical and medicolegal aspects of their care, and the therapeutic options available to clinicians. DATA SOURCES: A MEDLINE literature search (1980 to 1992) identified most studies. Other studies were selected from the bibliographies of identified articles. STUDY SELECTION: Selection of articles was limited to the history, philosophy, medicolegal and ethical issues, and clinical management of anemic Jehovah's Witnesses; a recent article on recommendations for red cell transfusion was also reviewed. CONCLUSIONS: A clear understanding of the philosophy of the Jehovah's Witnesses regarding blood transfusion and of the medicolegal and ethical aspects of their care is essential to clinicians who care for such patients. One must also be aware of the many alternative therapeutic options that can maximize oxygen delivery and minimize oxygen consumption. The insights gained from this review are applicable to any severely anemic patient who refuses blood transfusion.

A model of pulmonary granulomata induced by beryllium sulfate in the rat.

In humans beryllium is known to cause pulmonary granulomata which are histologically indistinguishable from sarcoidosis. There is some evidence in man that beryllium-induced pulmonary granulomata are immunologically mediated. We set out to develop an animal model to study the immunopathogenesis of beryllium-induced granulomatous lung disease. Beryllium sulfate (BeSO4) was injected intratracheally (i.t.) into F344 rats previously immunized to BeSO4. This results in well-formed, sarcoid-like lung granulomata at 6 weeks post BeSO4. There was a conspicuous presence at 4 weeks post BeSO4 of numerous, perivascularly located Langhans' giant cells which preceded the development of well-formed granulomas at 6 weeks. Rats were sacrificed at 4, 6, 8 and 12 weeks after i.t. BeSO4. At the time of sacrifice bronchoalveolar lavage (BAL) was performed; B and T (W3/25+ helper 0X8+ suppressor/cytotoxic) lymphocyte populations were quantitated and compared to lymphocyte populations obtained from lung tissue. Both B and T cells were significantly elevated in lung tissue post BeSO4. At 4 weeks when granulomata were just developing, a W3/25+ to 0X8+ ratio of 20:1 in lavage and 2:1 in lung tissue was seen. At 6 weeks when granulomata were well-formed there was a predominance of W3/25+ cells in lavage but not in lung tissue. At 8 and 12 weeks, when the granulomata were regressing, lavage fluid still contained a W3/25+ predominance in contrast to lung tissue which contained a predominance of 0X8+ cells.(ABSTRACT TRUNCATED AT 250 WORDS)