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Biomedical subjects

P N Lanken

Publications and source records attributed to P N Lanken.

At least 19 recordsLinked to original sources
PubMed2000

Dying patients in the intensive care unit: forgoing treatment, maintaining care.

End-of-life care of patients in the intensive care unit (ICU) often requires dramatic shifts in attitudes and interventions, from traditional intensive rescue care to intensive palliative care. The care of patients dying in ICUs raises both clinical and ethical difficulties. Because fewer ICU patients are able to make decisions about withdrawing treatment, careful attention must be paid to previously expressed preferences and surrogate input. Cultural and spiritual values of patients and families may differ markedly from those of clinicians. Although prognostic models are increasingly able to predict mortality rates for groups of ICU patients, their usefulness in guiding specific decisions to forego treatment has not been established. When a decision to forego treatment is made, the focus should be on specifying the patient's goals of care and assessing all treatments in light of these goals; interventions that do not contribute to the patient's goals should be discontinued. Symptoms accompanying withdrawal of life support can almost always be controlled with appropriate palliative measures. After ICU interventions are foregone, patient comfort must be the paramount objective. Whether in the ICU or elsewhere, hospitals have an ethical obligation to provide settings that offer dignified, compassionate, and skilled care.

Aged↗
PubMed2000

A picture archival and communication system shortens delays in obtaining radiographic information in a medical intensive care unit.

OBJECTIVE: To assess whether variables such as unit occupancy and aggregate severity of illness that reflect increased work demands on physicians in medical intensive care units (MICU) are associated with increased delays in their obtaining information about nonroutine chest radiographic examinations. To determine whether the presence of a picture archiving and communication system (PACS) workstation in the MICU shortens those delays. DESIGN: A prospective cohort study stratified for presence or absence of PACS. SETTING: MICU of a university hospital. PATIENTS: A total of 118 patients admitted to the MICU who had nonroutine bedside chest radiographs. MEASUREMENTS AND MAIN RESULTS: Multivariate analyses were conducted to determine how unit occupancy, patient acuity, the time of day the examination was taken, and the presence of a PACS workstation influenced the time from radiographic examination completion to the time when MICU physicians first obtained image information. In a multivariate analysis, patient acuity, unit occupancy, the aggregate level of severity of illness in the study cohort, whether the examination was taken at night or day, and the presence of a PACS workstation were significant predictors of the elapsed time from examination completion until review by MICU physicians. Without the PACS workstation, higher occupancy, higher aggregate severity of illness, and examinations taken during the day were associated with longer delays. Overall, the multivariate analysis showed a 24-min decrease in the elapsed time to obtain information during periods with the PACS workstation compared with periods without the workstation (p = .03). CONCLUSIONS: A PACS workstation significantly decreased the delays in obtaining image information that occurred with high unit occupancy and high aggregate severity of illness and may improve unit efficiency under conditions of high physician workload.

APACHE↗
PubMed2000

Plasma proteins modified by tyrosine nitration in acute respiratory distress syndrome.

The present study identifies proteins modified by nitration in the plasma of patients with ongoing acute respiratory distress syndrome (ARDS). The proteins modified by nitration in ARDS were revealed by microsequencing and specific antibody detection to be ceruloplasmin, transferrin, alpha(1)-protease inhibitor, alpha(1)-antichymotrypsin, and beta-chain fibrinogen. Exposure to nitrating agents did not deter the chymotrypsin-inhibiting activity of alpha(1)-antichymotrypsin. However, the ferroxidase activity of ceruloplasmin and the elastase-inhibiting activity of alpha(1)-protease inhibitor were reduced to 50.3 +/- 1.6 and 60.3 +/- 5.3% of control after exposure to the nitrating agent. In contrast, the rate of interaction of fibrinogen with thrombin was increased to 193.4 +/- 8.5% of the control value after exposure of fibrinogen to nitration. Ferroxidase activity of ceruloplasmin and elastase-inhibiting activity of the alpha(1)-protease inhibitor in the ARDS patients were significantly reduced (by 81 and 44%, respectively), whereas alpha(1)-antichymotrypsin activity was not significantly altered. Posttranslational modifications of plasma proteins mediated by nitrating agents may offer a biochemical explanation for the reported diminished ferroxidase activity, elevated levels of elastase, and fibrin deposits detected in patients with ongoing ARDS.

Acute Disease↗
PubMed1999

Incorporating palliative care into critical care education: principles, challenges, and opportunities.

OBJECTIVE: To identify the goals and methods for medical education about end-of-life care in the intensive care unit (ICU). DATA SOURCES AND STUDY SELECTION: A status report on palliative care, a summary report of recent research on palliative care education, articles in the medical literature on end-of-life care and critical care, and expert opinion were considered. DATA EXTRACTION: A working group, including specialists in critical care, palliative care, medical ethics, consumer advocacy, and communications, was convened at the "Medical Education for Care Near the End of Life National Consensus Conference." A modified nominal group process was used to develop a consensus. DATA SYNTHESIS: In the ICU, life and death decisions are often made in a crisis mode or in the face of uncertainty, and may necessitate the withholding and withdrawal of life-supporting technologies. Because critical illness often diminishes the capacity of patients to make decisions, clinicians must often make decisions in conjunction with surrogates, rather than with patients. Discontinuity of care can threaten trusting relationships, and cultural diversity can have a particularly powerful impact on choices for care. In the face of these realities, it is possible and appropriate to give compassionate palliative care to dying patients and their families in the ICU. CONCLUSIONS: Teaching care of the dying in the ICU should emphasize the following: a) the goals of care should guide the use of technology; b) understanding of prognostication and treatment withholding and withdrawal is essential; c) effective communication and trusting relationships are crucial to good care; d) cultural differences should be acknowledged and respected; and e) the delivery of excellent palliative care is appropriate and necessary when patients die in the ICU.

Attitude to Death↗
PubMed1998

Limulus amebocyte lysate assay for detection of endotoxin in patients with sepsis syndrome. AMCC Sepsis Project Working Group.

Clinical predictions alone are insufficiently accurate to identify patients with specific types of bloodstream infection; laboratory assays might improve such predictions. Therefore, we performed a prospective cohort study of 356 episodes of sepsis syndrome and did Limulus amebocyte lysate (LAL) assays for endotoxin. The main outcome measures were bacteremia and infection due to gram-negative organisms; other types of infection were secondary outcomes. Assays were defined as positive if the result was > or = 0.4 enzyme-linked immunosorbent assay units per milliliter. There were positive assays in 119 (33%) of 356 episodes. Assay positivity correlated with the presence of fungal bloodstream infection (P < .003) but correlated negatively with the presence of gram-negative organisms in the bloodstream (P = .04). A trend toward higher rates of mortality in the LAL assay-positive episodes was no longer present after adjusting for severity. Thus, results of LAL assay did not correlate with the presence of bacteremia due to gram-negative organisms or with mortality after adjusting for severity but did correlate with the presence of fungal bloodstream infection.

Bacteremia↗
PubMed1997

Epidemiology of sepsis syndrome in 8 academic medical centers.

CONTEXT: Sepsis syndrome is a leading cause of mortality in hospitalized patients. However, few studies have described the epidemiology of sepsis syndrome in a hospitalwide population. OBJECTIVE: To describe the epidemiology of sepsis syndrome in the tertiary care hospital setting. DESIGN: Prospective, multi-institutional, observational study including 5-month follow-up. SETTING: Eight academic tertiary care centers. METHODS: Each center monitored a weighted random sample of intensive care unit (ICU) patients, non-ICU patients who had blood cultures drawn, and all patients who received a novel therapeutic agent or who died in an emergency department or ICU. Sepsis syndrome was defined as the presence of either a positive blood culture or the combination of fever, tachypnea, tachycardia, clinically suspected infection, and any 1 of 7 confirmatory criteria. Estimates of total cases expected annually were extrapolated from the number of cases, the period of observation, and the sampling fraction. RESULTS: From January 4, 1993, to April 2, 1994, 12759 patients were monitored and 1342 episodes of sepsis syndrome were documented. The extrapolated, weighted estimate of hospitalwide incidence (mean+/-95% confidence limit) of sepsis syndrome was 2.0+/-0.16 cases per 100 admissions, or 2.8+/-0.17 per 1000 patient-days. The unadjusted attack rate for sepsis syndrome between individual centers differed by as much as 3-fold, but after adjustment for institutional differences in organ transplant populations, variation from the expected number of cases was reduced to 2-fold and was not statistically significant overall. Patients in ICUs accounted for 59% of total extrapolated cases, non-ICU patients with positive blood cultures for 11%, and non-ICU patients with negative blood cultures for 30%. Septic shock was present at onset of sepsis syndrome in 25% of patients. Bloodstream infection was documented in 28%, with gram-positive organisms being the most frequent isolates. Mortality was 34% at 28 days and 45% at 5 months. CONCLUSIONS: Sepsis syndrome is common in academic hospitals, although the overall rates vary considerably with the patient population. A substantial fraction of cases occur outside ICUs. An understanding of the hospitalwide epidemiology of sepsis syndrome is vital for rational planning and treatment of hospitalized patients with sepsis syndrome, especially as new and expensive therapeutic agents become available.

Adult↗
PubMed1997

Predicting bacteremia in patients with sepsis syndrome. Academic Medical Center Consortium Sepsis Project Working Group.

The goal of this study was to develop and validate clinical prediction rules for bacteremia and subtypes of bacteremia in patients with sepsis syndrome. Thus, a prospective cohort study, including a stratified random sample of 1342 episodes of sepsis syndrome, was done in eight academic tertiary care hospitals. The derivation set included 881 episodes, and the validation set included 461. Main outcome measures were bacteremia caused by any organism, gram-negative rods, gram-positive cocci, and fungal bloodstream infection. The spread in probability between low- and high-risk groups in the derivation sets was from 14.5% to 60.6% for bacteremia of any type, from 9.8% to 32.8% for gram-positive bacteremia, from 5.3% to 41.9% for gram-negative bacteremia, and from 0.6% to 26.1% for fungemia. Because the model for gram-positive bacteremia performed poorly, a model predicting Staphylococcus aureus bacteremia was developed; it performed better, with a low- to high-risk spread of from 2.6% to 21.0%. The prediction models allow stratification of patients according to risk of bloodstream infections; their clinical utility remains to be demonstrated.

Adult↗
PubMed1997

Routine portable chest radiographs in the medical intensive care unit: effects and costs.

OBJECTIVE: To determine the effects and net costs of routine chest radiographs in a medical intensive care unit (ICU). DESIGN: A prospective, cohort study. A survey of experts in critical care and pulmonary diseases was undertaken to assess the effect of routine radiographs on patient management. SETTING: Medical ICU of a university hospital. PATIENTS: Eighty randomly selected patients admitted to a medical ICU. Two hundred fourteen experts were surveyed; 118 (55%)/214 responded. MEASUREMENTS AND MAIN RESULTS: Daily interviews with medical ICU clinicians were conducted to assess the radiographic findings in the routine radiographs and actions taken based on these findings. Experts evaluated the findings, their importance, the actions taken, and the probability of complications if the actions had not been taken at that time. Experts also predicted increases in length of stay associated with these complications. Presence of radiographic findings, changes in management because of the findings, net costs of routine chest radiographs, cost per finding that prompted an action, and expected changes in length of stay resulting from the actions were also assessed. Seventy-two (33%) of 221 routine radiographs (95% confidence interval: 25% to 39%) had findings, of which 44 (61%) were judged important, and 18 (8%, 95% confidence interval: 5% to 12%) prompted actions. Experts predicted that each action averted, on average, 2.1 +/- 1.7 days (SD) in the medical ICU. Mean savings per routine radiograph was $98. Net savings from routine chest radiographs remained after sensitivity analysis for expected change in length of stay, percentage of patients with routine radiographs, and percentage of routine radiographs that produce changes in management. CONCLUSION: The policy of obtaining routine chest radiographs in the medical ICU is effective and results in net savings.

APACHE↗
PubMed1997

Ethics of allocating intensive care unit resources.

ICU clinicians commonly make decisions that allocate resources. Because of the high cost of ICU care, these practitioners can expect to be involved in the growing dilemma of trying to meet increasing demand for healthcare services within financial constraints. In order to participate meaningfully in a societal discussion over fairness in allocating scare and expensive resources, ICU practitioners should have more than a superficial knowledge of the principles of distributive justice. Distributive justice refers to fairness in the distribution of limited resources and benefits. Fairness refers to giving equal treatment to all those who are the same with regard to certain morally significant characteristics and treating in a different manner those who are not the same. Although theoretical issues remain unresolved as to which characteristics should be most significant, the United States has a strong cultural value that regards individuals as inherently valuable and having equal social worth. From this, it is likely that only an egalitarian approach to allocation of lifesaving healthcare resources will be acceptable. Studies of how ICU resources have been allocated during times of scarcity indicates that, in general, when beds are scarce, the average severity of illness of those admitted to the ICU increases. However, in some hospitals, political and economic factors appear to play important roles in determining who has access to scarce ICU beds. Of great concern is documentation of a widespread pattern in which fewer hospital resources, including ICU resources, are provided to seriously ill patients of minority status or with low levels of insurance reimbursement. How society's values get translated into allocation decisions is another unresolved issue. One recent example of how this occurred is the Oregon Medicaid Plan. This plan extended Medicaid coverage to additional people in poverty, despite the same amount of state and federal funds. This was accomplished by not reimbursing what were regarded as marginally beneficial services on the basis of medical and community input. Portents of how society might be involved in the future of health care are illustrated by the argument that society should limit access to all therapies except palliative care solely on the basis of advanced age. Until an open consensus develops in U.S. society about how to allocate scarce healthcare resources, the delivery of ICU care will continue to be at risk of covert, de facto rationing based on ability to pay, race, or other nonmedical personal characteristics.

Cost Control↗
PubMed1996

Prospective study of a PACS: information flow and clinical action in a medical intensive care unit.

PURPOSE: To prospectively compare efficiency and outcome of a standard film-only system with those of a digital picture archiving and communication system (PACS). MATERIALS AND METHODS: The film-only system, which used either analog film or computed radiography (CR) hard copy, was compared with a PACS, which used CR images displayed on a multiviewer in the radiology department and a workstation in the medical intensive care unit. A random sample of nonroutine, bedside chest radiographs was studied. RESULTS: Within 20 minutes of completion of radiography, 246 of 328 (75%) of the images were available at the workstations; it took 1.8 hours for 238 of 317 (75%) of the images to be displayed on the multiviewer. When the workstation was used, the staff did not access the image information earlier, but clinical actions were initiated more promptly in response to imaging findings. Consultation with radiologists decreased from 507 of 561 (90%) images with hard copies to 70 of 249 (28%) with the workstation. CONCLUSION: Use of a PACS improves the delivery of chest images, facilitates the initiation of clinical actions, and decreases input by radiologists.

Computer Systems↗
PubMed1996

Factors affecting the electronic communication of radiological information to an intensive-care unit.

In order to examine communication of radiological information under circumstances where rapid exchange of information was essential, we studied communication of non-routine portable chest radiographs to an intensive-care unit (ICU). Images and reports were available through the usual communication channels and through a PACS workstation in the ICU. Data were obtained to determine how quickly and by what means ICU physicians first viewed images and received radiologists' reports of chest radiographs. Peak information demand occurred within 4 h of the examination. The most rapid means of communication was for the physician to visit the radiology department. Image viewing and report receipt were tightly coupled, usually for images which were first viewed as hard copy. PACS performance suffered from unreliable film digitization and delayed report transcription. Integration of computed radiography and digital dictation into a PACS could markedly reduce the delays in ICU physicians' access to radiological information.

Efficiency, Organizational↗
PubMed1995

Decisions to limit or continue life-sustaining treatment by critical care physicians in the United States: conflicts between physicians' practices and patients' wishes.

We surveyed a national sample of 879 physicians practicing in adult intensive care units in the United States, in order to determine their practices with regard to limiting life-sustaining medical treatment, and particularly their decisions to continue or forgo life support without the consent or against the wishes of patients or surrogates. Virtually all of the respondents (96%) have withheld and withdrawn life-sustaining medical treatment on the expectation of a patient's death, and most do so frequently in the course of a year. Many physicians continue life-sustaining treatment despite patient or surrogate wishes that it be discontinued (34%), and many unilaterally withhold (83%) or withdraw (82%) life-sustaining treatment that they judge to be futile. Some of these decisions are made without the knowledge or consent of patients or their surrogates, and some are made over their objections. We conclude that physicians do not reflexively accept requests by patients or surrogates to limit or continue life-sustaining treatment, but place these requests alongside a collection of other factors, including assessments of prognosis and perceptions of other ethical, legal, and policy guidelines. While debate continues about the ethical and legal foundations of medical futility, our results suggest that most critical care physicians are incorporating some concept of medical futility into decision making at the bedside.

Adult↗
PubMed1994

HA-1A in septic patients with ARDS: results from the pivotal trial.

OBJECTIVE: To evaluate the effects of HA-1A, a human monoclonal antiendotoxin antibody, in septic patients with ARDS. DESIGN: Substudy of a multicenter, double-blinded, placebo-controlled trial of HA-1A in septic patients. PATIENTS: 63 septic patients with ARDS at the time of study entry. INTERVENTION: A single intravenous injection of HA-1A (100 mg) or placebo. RESULTS: A quantitative radiographic score, the PaO2/FIO2 ratio and an index of the severity of ARDS did not show a significant difference between the treatment and placebo groups at 3, 5 and 7 days after treatment. The duration of endotracheal intubation did not differ between the two groups. 15 of 30 HA-1A treated patients (50%) and 23 of 33 placebo-treated patients (69.7%) died within 28 days. The daily mortality was always lower in the HA-1A group, but this difference was not statistically significant at 28 days. The 28-day survival curves for the two treatment groups adjusted by covariate analysis were not significantly different (p = 0.07). Using logistic regression, a significant independent effect of HA-1A treatment was detected upon the early survival rate at 7 days (p = 0.03) but not at 14 and 28 days. CONCLUSION: A single injection of HA-1A in septic patients with ARDS did not reverse acute respiratory failure or improve long-term survival.

Adult↗
PubMed1994

High-resolution image workstation for intensive care units.

Despite their potential for improving patient management and decreasing costs, picture archiving and communication systems (PACS) are not being absorbed rapidly into clinical practice because of their technical immaturity and because the cost-effectiveness of the technology has not been established. Workstations and archives need to be significantly improved before they can be useful. This report describes the authors' experiences with a high-resolution image workstation for a medical intensive care unit. The workstation has been designed around a standard computer platform and is equipped with two high-resolution image displays. The user interface stresses speed and simplicity. Image manipulation is simplified by providing empirical preset window and level values. Images are displayed in less than 2 seconds. The workstation also displays radiologic reports as soon as they become available. Future work will focus on using the workstation to improve communication between the physician and the radiologist.

Humans↗