Biomedical subjects

P E Bellamy

Publications and source records attributed to P E Bellamy.

17 recordsLinked to original sources

PubMed1995

The SUPPORT prognostic model. Objective estimates of survival for seriously ill hospitalized adults. Study to understand prognoses and preferences for outcomes and risks of treatments.

OBJECTIVE: To develop and validate a prognostic model that estimates survival over a 180-day period for seriously ill hospitalized adults (phase I of SUPPORT [Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments]) and to compare this model's predictions with those of an existing prognostic system and with physicians' independent estimates (SUPPORT phase II). DESIGN: Prospective cohort study. SETTING: 5 tertiary care academic centers in the United States. PARTICIPANTS: 4301 hospitalized adults were selected for phase I according to diagnosis and severity of illness; 4028 patients were evaluated from phase II. MEASUREMENTS: A survival model was developed using the following predictor variables: diagnosis, age, number of days in the hospital before study entry, presence of cancer, neurologic function, and 11 physiologic measures recorded on day 3 after study entry. Physicians were interviewed on day 3. Patients were followed for survival for 180 days after study entry. RESULTS: The area under the receiver-operating characteristics (ROC) curve for prediction of surviving 180 days was 0.79 in phase I, 0.78 in the phase II independent validation, and 0.78 when the acute physiology score from the APACHE (Acute Physiology, Age, Chronic Health Evaluation) III prognostic scoring system was substituted for the SUPPORT physiology score. For phase II patients, the SUPPORT model had equal discrimination and slightly improved calibration compared with physician's estimates. Combining the SUPPORT model with physician's estimates improved both predictive accuracy (ROC curve area = 0.82) and the ability to identify patients with high probabilities of survival or death. CONCLUSIONS: A limited amount of readily available clinical information can provide a foundation for long-term survival estimates that are as accurate as physicians' estimates. The best survival estimates combine an objective prognosis with a physician's clinical estimate.

APACHE↗

PubMed1994

Prior capacity of patients lacking decision making ability early in hospitalization: implications for advance directive administration. The SUPPORT Investigators. Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments.

OBJECTIVE: To investigate the appropriateness of hospitalization as the time to elicit patients' medical care preferences, the authors evaluated the capability of seriously ill patients to participate in decision making early in hospitalization and their decision making capacity two weeks before hospital entry. DESIGN: Cross-sectional study with retrospective evaluation of preadmission decision making capacity. SETTING: Five acute care teaching hospitals. PATIENTS: Four thousand three hundred one acutely ill hospitalized adults meeting predetermined severity of illness criteria in nine specific disease categories. MEASUREMENTS: Surrogate decision makers' estimates of the prior mental capacities of patients unable to be interviewed early in hospitalization about care preferences due to intubation, coma, or cognitive impairment. Comparison of the demographics, degrees of sickness at admission, and outcomes of interviewable vs noninterviewable patients. MAIN RESULTS: Forty percent of the patients were not interviewable concerning preferences. Of these, 83% could have participated in treatment decisions two weeks prior to hospitalization. The patients who were not interviewable were more acutely ill, had less chronic disease, and were more likely to die during hospitalization than the interviewable patients. CONCLUSIONS: Many acutely ill patients likely to die in the hospital lost their ability to make medical care decisions around the time of hospital admission. Preferences for care and advance directives should be discussed in the outpatient setting or very early in hospital admission.

Advance Directives↗

PubMed1994

Survival outcome among 54 intubated pediatric bone marrow transplant patients.

OBJECTIVES: To assess the outcome of children who required endotracheal intubation after bone marrow transplantation and to determine whether prognostic indicators that might assist decision-making regarding the institution of mechanical ventilation could be identified. DESIGN: Retrospective chart review. SETTING: Critical care, reverse isolation unit at a university hospital. PATIENTS: Fifty-four pediatric bone marrow transplant recipients who required endotracheal intubation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The following variables were assessed for effect on survival: a) the presence of additional nonhematoporetic organ system failure; b) the duration of required ventilatory assistance; c) the etiology of respiratory failure; d) the presence of significant graft vs. host disease; and e) the underlying disease for which the transplant was done. Six of 54 intubated pediatric bone marrow transplant recipients were extubated and discharged from the hospital. No patient with a diagnosis of leukemia or with multiple organ system failure could be extubated or discharged from the hospital. The presence of pulmonary parenchymal disease indicated poor prognosis for survival. CONCLUSIONS: The decision to intubate a pediatric bone marrow transplant patient remains a difficult one. In this population, multiple organ system failure and primary pulmonary parenchymal disease were associated with a high mortality rate. These factors should be taken into account before and throughout the course of mechanical ventilation in this patient population.

Adolescent↗

PubMed1994

Effect of do-not-resuscitate orders on the nursing care of critically ill patients.

BACKGROUND: The effect of a do-not-resuscitate order on the standard of care of critically ill patients is of concern to practitioners, patients, and their families. Because "do not resuscitate" may be misconstrued to include more than "no cardiopulmonary resuscitation," it may influence the aggressiveness with which some patients are managed. Nurses play a central role in determining standards of care. Hence, confusion on their part as to the meaning of this term can have a significant impact on patient care. OBJECTIVES: To compare nurses' attitudes about standards of care for critically ill patients with and without a do-not-resuscitate order. METHOD: A quasi-experimental design using simulation measurement was used for this study. RESULTS: Nurses reported that they would be significantly less likely to perform a variety of physiologic monitoring modalities and interventions for patients with a do-not-resuscitate order than for patients without such an order. Patients with a do-not-resuscitate order were more likely to receive psychosocial interventions including assessment of their spiritual needs and more flexible visiting practices. CONCLUSIONS: Our findings suggest that "do-not-resuscitate" may be misinterpreted to include more than "no cardiopulmonary resuscitation" even if the patient is receiving aggressive medical management. Misinterpretation of orders not to resuscitate may be related to a variety of factors including lack of understanding about hospital policy and ethical and moral values of the staff. We suggest replacing orders such as "Do not resuscitate" with clearly defined resuscitation plans that are jointly determined by the multidisciplinary team, patient, and family.

Adult↗

PubMed1991

Patterns of resource consumption in medical intensive care.

Intensive care is being scrutinized as a major factor in increasing health care costs. We examined 404 consecutive admissions to the medical ICUs at a university medical center to study patterns of consumption of ICU resources and the proportion of resources used by patients admitted for monitoring only. We found a skewed distribution of ICU resource consumption, with the "high-cost" 8 percent using as many ICU resources as the "low-cost" 92 percent. Forty-one percent of admissions did not receive acute ICU treatments, but these admissions consumed less than 10 percent of ICU resources. Reducing the number of patients admitted for monitoring will have a relatively small impact on hospital charges. Since over 70 percent of the high-cost patients died, improved understanding of prognosis and better physician-patient communication may substantially reduce the proportion of critical care resources expended on futile treatment.

Academic Medical Centers↗

PubMed1991

Pulmonary dysfunction in advanced liver disease: frequent occurrence of an abnormal diffusing capacity.

PURPOSE: Abnormalities in pulmonary function have been reported in association with chronic liver disease of varied etiology. The aim of this study was to better define the frequency and nature of these abnormalities in patients who were being evaluated for liver transplantation. PATIENTS AND METHODS: We performed a battery of pulmonary function tests and chest radiographs in 116 consecutive patients (50 men, 66 women; aged 19 to 70 years, mean 44.6 years) with severe advanced liver disease who were hospitalized specifically for evaluation for possible orthotopic liver transplantation and were able to perform technically satisfactory tests. In 17 patients, quantitative whole-body technetium-99m macroaggregated albumin perfusion scanning was also performed for assessment of possible right-to-left shunting through intrapulmonary vascular dilatations. RESULTS: The most commonly affected test of lung function was the single-breath diffusing capacity for carbon monoxide (DLCO), which was abnormal in 48%, 45%, and 71% of patients who never smoked, former smokers, and current smokers, respectively. Ventilatory restriction was noted in 25% of all patients, airflow obstruction (reduced ratio of forced expiratory volume in 1 second to forced vital expiratory volume in 1 second to forced vital capacity) in only 3%, and a widened alveolar-arterial oxygen gradient in 45%. Diffusion impairment was accompanied by a restrictive defect in only 35% of the patients and by an abnormally widened alveolar-arterial oxygen gradient in 60%. When diffusion impairment was accompanied by an oxygenation defect, it was also associated with a significantly increased right-to-left shunt fraction (mean 24.9%) assessed from quantitative whole-body perfusion imaging. On the other hand, isolated diffusion impairment unaccompanied by significant hypoxemia (noted in approximately a third of the patients with a reduced DLCO) was not associated with evidence of significant intrapulmonary shunting (mean right-to-left shunt fraction 6.7%). CONCLUSIONS: Most patients with advanced liver disease have one or more types of abnormality in lung function, a reduced DLCO being the single most common functional defect. Mechanisms accounting for the abnormality in gas transfer may include intrapulmonary vascular dilatations, diffuse interstitial lung disease, pulmonary vaso-occlusive disease, and/or ventilation-perfusion imbalance.

Adult↗

PubMed1990

Ventilatory and diffusion abnormalities in potential heart transplant recipients.

Few data are available concerning pulmonary function in patients with severe chronic congestive heart failure. Of 315 patients evaluated for potential cardiac transplantation at UCLA, 132 underwent pulmonary function tests. The latter patients had severe heart failure with a mean left ventricular ejection fraction of 19 percent and mean cardiac index of 2.1 L/min/m2. Diffusion impairment either alone or combined with restrictive and/or obstructive ventilatory defects occurred in 67 percent of the patients evaluated. Diffusion impairment occurred as the sole abnormality in 31 percent of the patients and in combination with a restrictive ventilatory defect in 21 percent. A reduction in diffusing capacity has not been previously described as a frequent finding in patients with chronic congestive heart failure. In contrast to other studies involving patients with acute heart failure, obstructive ventilatory defects were uncommon. None of the lung function abnormalities was associated with smoking status, prior drug use, chest roentgenographic changes, hemodynamic findings, or clinical features, including duration of congestive heart failure. The mechanism for the diffusion impairment is unclear but could be due to chronic passive congestion with pulmonary fibrosis and/or recurrent pulmonary emboli. Recognition of diffusion impairment as a common finding in patients with severe chronic congestive heart failure who are candidates for heart transplantation is important for proper interpretation of possible post-transplant changes in diffusing capacity due to other causes.

Adult↗

PubMed1989

Efficacy of intensive care for bone marrow transplant patients with respiratory failure.

We reviewed the ICU courses of 50 bone marrow transplant recipients treated for respiratory problems. Seven of nine postoperative patients survived compared to one of 40 patients with progressive interstitial pneumonia. Nonsurvivors accounted for 94% of the ICU days, 98% of intubated days, and 99% of blood products used. All survivors were extubated within 4 days. Intensive respiratory care is effective for patients with readily reversible causes of respiratory failure, but is generally futile for patients with progressive interstitial pneumonia. We recommend providing these patients with realistic prognostic estimates early in their treatment.

Adult↗

PubMed1989

Diaphragmatic contraction during assisted mechanical ventilation.

Indirect evidence from airway pressure recordings in mechanically ventilated patients suggests that the diaphragm exhibits contractile activity beyond that required to trigger a ventilator-assisted breath. We used the diaphragmatic EMG to provide direct evidence of persistent contractile activity and studied the effects of alterations in ventilator-delivered flow rate and tidal volume on the duration of diaphragmatic contraction. The duration of contraction was expressed in terms of inspired volume. During a single breath, diaphragmatic force generation ceases at the point of peak electromyographic activity; hence, the inspired volume at peak EMG is the volume at the diaphragmatic off-switch (Voff). Ventilator-delivered flow rate and tidal volume were varied during assisted (patient-initiated) and controlled (ventilator-initiated) breaths while diaphragmatic EMG and inspired volume were recorded simultaneously in ten patients with a variety of illnesses requiring mechanical ventilation. Spontaneous ventilator-unassisted breaths were also recorded for comparison. We found that (1) during assisted breaths, diaphragmatic activity continued after the ventilator was triggered, (2) Voff was usually close to spontaneous tidal volume, (3) Voff increased significantly as ventilator-delivered flow rate increased, and (4) controlled breaths may also be associated with phasic electromyographic activity. The data have implications for resting patients on assisted ventilation.

Adult↗

PubMed1989

Attitudes of hospitalized patients toward life support: a survey of 200 medical inpatients.

PURPOSE: Life-support decisions have profound medical, ethical, and economic implications; yet little is known about inpatients' preferences for life-sustaining treatments. We therefore conducted a prospective survey of medical inpatients to determine attitudes toward life support under differing medical outcomes, and the extent of physician communication about these issues. PATIENTS AND METHODS: The study population consisted of 200 adult patients admitted to the general medical services at UCLA Medical Center during August and September 1987. Each patient completed a standardized 13-item questionnaire. Patients rated their agreement with life-support treatment in the context of four outcome scenarios. A five-point Lickert scale for each question was used, and an overall life-support scale was created by summing the four items. Patients were also asked about previous life-support discussions with their physicians. RESULTS: Life support was desired in 90 percent of the patients if their health could be restored to its usual level, in 30 percent if they would be unable to care for themselves after discharge, in 16 percent if their chance for recovery was hopeless, and in only 6 percent if they would remain in a vegetative state. Patients who desired less aggressive care were older, female, and more likely to have terminal illnesses. Only 16 percent reported having discussed life support with their physicians; however, an additional 47 percent desired such discussions. CONCLUSION: Hospitalized medical patients base their preferences for life support upon perceived outcomes. Lack of communication creates the potential for patients to be subjected to burdensome and expensive treatments they may not desire. We encourage physicians to offer their patients discussions about prognosis and the efficacy of life support so that disproportionate treatments can be avoided.

Adult↗

PubMed1988

Gas flow through a bronchopleural fistula. Measuring the effects of high-frequency jet ventilation and chest-tube suction.

High-frequency jet ventilation (HFJV) is FDA-approved for ventilating patients with bronchopleural fistulae (BPF), yet little is known about its effect on the fistula airleak. We quantitated a patient's BPF airleak during both conventional volume-cycled ventilation and HFJV. The effect of chest-tube suction (CTS) on BPF flow was also studied. Despite a significant reduction in peak airway pressure, the HFJV resulted in a 50-70 percent increase in BPF flow. CTS also significantly increased the airleak. HFJV may not always be the preferential method for ventilating patients with BPF and we recommend measuring the fistula airleak when attempting to optimize a patient's ventilatory parameters.

Adult↗

PubMed1987

Admitting elderly patients to the ICU: dilemmas and solutions.

Since intensive care is expensive and has limited efficacy, its use should be reserved primarily for patients with acute, reversible illnesses. Although age is related to ICU mortality, more important predictors of ICU outcome are severity of the acute illness, the admitting diagnosis, and previous health status. Thus, age should not be the sole factor considered prior to ICU transfer or the initiation or denial of resuscitative efforts. Geriatric physicians should prospectively develop individualized plans for each of their patients based upon the patients' wishes after a discussion of diagnosis, prognosis, and the likely efficacy and side effects of the available treatments.

Aged↗

PubMed1986

An alternative method for coordinating pulmonary capillary wedge pressure measurements with the respiratory cycle.

Changes in intrathoracic pressure during the respiratory cycle cause variations in pulmonary vascular pressures. This affects pulmonary hemodynamic measurements in critically ill patients, particularly those receiving mechanical ventilation. With certain newer ventilators, the machine-pressure and/or expiratory-flow signal can be graphed simultaneously with hemodynamic pressure. The end-expiratory point determined from these graphs can be used to identify the corresponding wedge pressure on the hemodynamic tracing.

Critical Care↗

PubMed1986

Assessing illness severity and outcome in critically ill patients.

Severity of illness scores have great potential to improve use of scarce resources and to help monitor quality of care. Injury severity scores can reliably separate trauma patients into high- and low-mortality groups, but have limitations when applied in triage decision making. Specific predictive models for chest pain patients have improved admitting practices in some emergency departments. Univariate predictors of survival include age, severity of illness, and presence of chronic illnesses, especially cancer. General multivariate models for intensive care patients have correctly categorized hospital outcome in approximately 85 per cent of cases when applied in a retrospective fashion. These models are insufficiently precise for application to individual patients; but they may be helpful in assessing quality of care in the intensive care unit, in assessing efficacy of new technologies, and in utilization review audits.

Age Factors↗

PubMed1984

Cyclic nucleotide concentrations in tissue and perfusate of isolated rat lung.

Cyclic nucleotide content of lung tissue is altered by anesthesia, ventilatory pattern, and pharmacologic manipulation (e.g., isoproterenol). In addition the lung releases cyclic nucleotides into its circulation, but little is known about factors that might alter this release. We isolated and perfused rat lungs (IPL) to determine: 1) if cyclic nucleotides are released into the perfusate in the control state; and 2) if their release changes after alteration of the ventilatory pattern or the addition of isoproterenol. We demonstrated that the rat IPL releases both cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) into the perfusate. Isoproterenol has no effect on cGMP release but increases cAMP release dramatically. Perfusate cAMP is not affected by ventilatory pattern, but perfusate cGMP is higher during high-pressure ventilation than it is in nonventilated or normally ventilated lungs.

Animals↗

PubMed1984

Adult respiratory distress syndrome: hospital charges and outcome according to underlying disease.

We reviewed the hospital charges, underlying diagnoses, and hospital outcomes in 39 patients with adult respiratory distress syndrome (ARDS) admitted to the respiratory ICU of a university hospital between July 1979 and June 1981. Charges per patient ranged from $9263 to $187,893 with a median of $52,894. Median ICU charges were $2430/day. Only 7 patients survived their hospitalization. Compared to nonsurvivors, survivors had longer ICU and hospital stays but lower daily ICU charges ($1683 vs. $2760,p = .001). Only 1 of 27 patients with underlying hematologic/oncologic diseases survived, compared to 6 of 12 patients with other underlying diseases. Charges and outcomes in this study reflect the underlying patient population and philosophy of care at the study institution. Considering the high costs and poor outcomes in ARDS patients with underlying hematologic/oncologic problems, we recommend that the appropriateness of aggressive treatment be reconsidered.

Adolescent↗

PubMed1982

Pulmonary function in patients with relapsing polychondritis.

Relapsing polychondritis is a disease characterized by progressive inflammation of cartilagenous structures including those of the glottis, trachea, or central bronchi. We performed detailed physiologic and radiologic studies of the respiratory tract in five patients with respiratory involvement due to relapsing polychondritis. We found that the maximal expiratory and inspiratory flow-volume loop and airway resistance together can provide useful clues as to the presence, site, and fixed or dynamic nature of the upper airway obstruction in these patients. However, in patients with fixed upper airway obstruction or compound lesions, computer tomography of the respiratory tract, cinetracheography, or laryngotracheograms at different lung volumes were required to identify the site of the obstruction and to clarify the dynamic nature of the obstruction.

Adult↗