Ventilator Settings Can Substantially Impact Patients' Comfort.

BACKGROUND: With increasing realization that sedatives may complicate care of mechanically ventilated patients, greater emphasis might turn to promoting comfort by titration of ventilator settings. HYPOTHESIS: Patients with acute on chronic respiratory failure (ACRF) with underlying chronic obstructive pulmonary disease (COPD) demonstrate different levels of comfort in response to varying ventilator settings compared to those with underlying obesity hypoventilation syndrome (OHS). METHODS: Patients recovering from ACRF with underlying COPD or OHS were randomized to varying combinations of ventilator modes (assist control and pressure support), tidal volumes, and inspiratory flows for 3 minutes/setting. For each ventilator setting, physiologic variables were recorded and patients indicated their level of comfort using a 10-point Borg scale. RESULTS: In all, 20 patients, aged 68 ± 13 years (standard deviation) and ventilated for 4.9 days, were enrolled. Of 20 patients, 13 had COPD and 7 had OHS. No ventilator mode, flow, or tidal volume provided consistently greater comfort between the groups, but patients reported substantial ranges of comfort (up to 8 Borg points) across the ventilator settings studied. There were no significant differences in heart rate, blood pressure, or airway pressures within patients across ventilator settings or between the groups, but patients with OHS were more tachypneic compared to patients with COPD while breathing on assist control of 6 mL/kg (constant flow 60 L/min) and 8 mL/kg (decelerating flow 40 L/min). There was no correlation between comfort and systolic blood pressure, heart rate, or respiratory rate. CONCLUSION: Ventilator parameters may impact patients' comfort substantially. Future studies may help identify evidence-based methodology for gauging comfort following changes in ventilator settings and the settings that are most likely to positively impact various groups of patients.

Perseverant, non-indicated treatment of obese patients for obstructive lung disease.

BACKGROUND: Bronchodilators are a mainstay of treatment for patients with airflow obstruction. We hypothesized that patients with obesity and no objective documentation of airflow obstruction are inappropriately treated with bronchodilators. METHODS: Spirometric results and medical records of all patients with body mass index >30 kg/m2 who were referred for testing between March 2010 and August 2011 were analyzed. RESULTS: 155 patients with mean age of 52.6 ± (SE)1.1 y and BMI of 38.7 ± 0.7 kg/m2 were studied. Spirometry showed normal respiratory mechanics in 62 (40%), irreversible airflow obstruction in 36 (23.2%), flows suggestive of restriction in 35 (22.6%), reversible obstruction, suggestive of asthma in 11 (7.1%), and mixed pattern (obstructive and restrictive) in 6 (3.9%). Prior to testing, 45.2% (28 of 62) of patients with normal spirometry were being treated with medications for obstructive lung diseases and 33.9% (21 of 62) continued them despite absence of airflow obstruction on spirometry. 60% (21 of 35) of patients with a restrictive pattern in their spirometry received treatment for obstruction prior to spirometry and 51.4% (18 of 35) continued bronchodilator therapy after spirometric testing. There was no independent association of non-indicated treatment with spirometric results, age, BMI, co-morbidities or smoking history. All patients with airflow obstruction on testing who were receiving bronchodilators before spirometry continued to receive them after testing. CONCLUSION: A substantial proportion of patients with obesity referred for pulmonary function testing did not have obstructive lung disease, but were treated nonetheless, before and after spirometry demonstrating absence of airway obstruction.

Outcomes of critically ill patients who received cardiopulmonary resuscitation.

RATIONALE: Studies examining survival outcomes after in-hospital cardiopulmonary arrest (CPA) among intensive care unit (ICU) patients requiring medications for hemodynamic support are limited. OBJECTIVES: To examine outcomes of ICU patients who received cardiopulmonary resusitation. METHODS: We identified 49,656 adult patients with a first CPA occurring in an ICU between January 1, 2000 and August 26, 2008 within the National Registry of Cardiopulmonary Resuscitation. Survival outcomes of patients requiring hemodynamic support immediately before CPA were compared with those of patients who did not receive hemodynamic support (pressors), using multivariable logistic regression analyses to adjust for differences in demographics and clinical characteristics. Pressor medications included epinephrine, norepinephrine, phenylephrine, dopamine, dobutamine, and vasopressin. MEASUREMENTS AND MAIN RESULTS: The overall rate of survival to hospital discharge was 15.9%. Patients taking pressors before CPA were less likely to survive to discharge (9.3 vs. 21.2%; P < 0.0001). After multivariable adjustment, patients taking pressors before pulseless CPA were 55% less likely to survive to discharge (adjusted odds ratio [OR], 0.45; 95% confidence interval [CI], 0.42-0.48). Age equal to or greater than 65 years (adjusted OR, 0.77; 95% CI, 0.73-0.82), nonwhite race (adjusted OR, 0.58; 95% CI, 0.54-0.62), and mechanical ventilation (adjusted OR, 0.60; 95% CI, 0.56-0.63) were also variables that could be identified before CPA that were independently associated with lower survival. More than half of survivors were discharged to rehabilitation or extended care facilities. Only 3.9% of patients who had CPA despite pressors were discharged home from the hospital, as compared with 8.5% of patients with a CPA and not taking pressors (adjusted OR, 0.53; 95% CI, 0.49-0.59). CONCLUSIONS: Although overall survival of ICU patients was 15.9%, patients requiring pressors and who experienced a CPA in an ICU were half as likely to survive to discharge and to be discharged home than patients not taking pressors. This study provides robust estimates of CPR outcomes of critically ill patients, and may assist clinicians to inform consent for this procedure.

Individualized education plans in medical education.

BACKGROUND: Individualized education plans (IEP) are commonly used in nonmedical educational programs to define students' deficiencies and action plans for addressing them. There are no reports of using IEP for medical education. SETTING: Internal medicine residency of a community teaching hospital. METHODS: Residents requiring IEP were identified by a consensus of faculty members. IEPs, overseen by mentors, included: 1. List of deficiencies, 2. Techniques for remediation, 3. Schedule for meetings and re-evaluation of IEP progress. Demographic and evaluative data were abstracted from the performance files of internal medicine residents who served in the program between 2003 and 2010. Characteristics and educational outcomes of those receiving IEPs were compared to those not requiring IEPs. RESULTS: Of 92 residents, 16 received IEPs; 13 for medical knowledge, four for professionalism and one for communication.Average age was greater (35.2 vs 30.3 y; P=0.004) and graduation less recent (8.7 vs 4.8 y; P=0.03). USMLE step I and American Board of Internal Medicine in-service scores were lower in those with IEP (82.6 vs 89.4; P=0.001; 44.6 vs 68.5 percentile relative to same-PGY level; P=0.01). Three residents repeated a PGY year (two successfully) and four completed two to six extra months at the same PGY level. All but two residents in the program between 2003 and 2010 passed Boards on their first attempt; neither had an IEP. Of the 12 with successful IEPs, three graduated to primary-care positions, two to hospitalist positions, and six to subspecialty fellowships; one was lost to follow-up. CONCLUSION: A formal IEP process similar to that employed in nonmedical education was associated with successful graduation and board certification in a majority of medical trainees who required remediation.

Are international and American graduates equally ACGME competent? Results of a pilot study.

BACKGROUND: Despite a substantial proportion of international medical graduates (IMG) matching to U.S. programs in Internal Medicine, little is known about their readiness in the six medical competencies compared to graduates of U.S. schools (USMG). METHODS: A brief questionnaire with two questions designed to assess basic understanding of each of the six medical competencies (knowledge, patient care, communication, professionalism, systems based- and practice-based learning) was sent by electronic mail to all 1,737 applicants to a community teaching hospital Categorical Internal Medicine Residency Program. Correct responses of IMG were compared to USMG. RESULTS: Two hundred and eight IMGs were similar except for older age (29 vs 27 years; P = 0.02) compared to 39 USMGs who responded. USMG and IMG had similar percent correct answers (67% vs 62%; P = 0.22). USMG and IMG scored similarly across all but two of the six medical competencies. USMGs more often answered correctly questions on U.S. healthcare economics (39.5% vs 20.4% correct, P = 0.01) and the elements of practice-based learning (69.2% vs 47.5%; P = 0.01). CONCLUSIONS: While this study is limited by its small sample size, it supports a hypothesis that USMG and IMG may differ in their preparedness for systems-based and practice-based learning. This hypothesis deserves exploration in future studies.

Rapid reversal of acute kidney injury and hospital outcomes: a retrospective cohort study.

BACKGROUND: Acute kidney injury (AKI), defined as an increment in serum creatinine level of 0.3 mg/dL or greater in 48 hours, is associated with poor outcomes. The prognosis associated with an increased creatinine level, either on admission or that develops in the hospital (ie, AKI), that rapidly returns to normal is not known. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: 6,033 patients admitted to medical wards of a community teaching hospital between 2005 and 2007. PREDICTOR: AKI was defined as an increase in serum creatinine level of 0.3 mg/dL or greater within 48 hours. Increased serum creatinine level on admission was defined as serum creatinine greater than1.2 mg/dL on hospital admission in patients who did not subsequently meet criteria for AKI. Patients with a serum creatinine level of 1.2 mg/dL or less who had no increase of 0.3 mg/dL or greater within 48 hours during their hospital stay served as controls. OUTCOMES & MEASUREMENTS: Mortality, length of stay, intensive care unit transfer, and discharge destination were outcomes of interest. RESULTS: Of 6,033 patients, 735 had AKI. Of these, 443 (60%) had serum creatinine levels that subsequently decreased by 0.3 mg/dL or greater within 48 hours and 197 returned to normal levels within 48 hours. Overall, patients with AKI had significantly greater mortality rates (14.8%) than patients without AKI with increased serum creatinine levels on admission (2.5%) and controls (1.3%; P < 0.001). Patients with AKI with a serum creatinine level that returned to normal within 48 hours had substantially greater mortality rates (14.2%) than those who initially presented with an increased serum creatinine level on admission and subsequent serum creatinine level decrease of 0.3 mg/dL or greater to normal within 48 hours (2.5%; P < 0.01). LIMITATIONS: Sample sizes of subgroups were small. Causes of AKI and increases in serum creatinine levels on admission were not assessed. CONCLUSIONS: An increase in serum creatinine level of 0.3 mg/dL or greater during 48 hours of hospitalization predicts outcomes even if the value returns to normal. Patients who present to the hospital with an increased creatinine level that returns rapidly to normal have outcomes approaching those with serum creatinine levels consistently in the normal range.

Acute kidney injury criteria predict outcomes of critically ill patients.

OBJECTIVE: The Acute Kidney Injury Network's proposed definition for acute kidney injury (increment of serum creatinine > or = 0.3 mg/dL or 50% from baseline within 48 hrs or urine output < 0.5 mL/kg/hr for > 6 hrs despite fluid resuscitation when applicable) predicts meaningful clinical outcomes. DESIGN: Retrospective cohort study. SETTING: A 350-bed community teaching hospital. PATIENTS: The study population consisted of 471 patients with no recent history of renal replacement therapy who were admitted to the medical intensive care unit during 1 yr. INTERVENTIONS: Medical records of all patients were reviewed using a data abstraction tool. Demographic information, diagnoses, risk factors for acute kidney disease, physiologic and laboratory data, and outcomes were recorded. MEASUREMENTS AND MAIN RESULTS: Of 496 patients, 471 were not receiving renal replacement therapy in the weeks before medical intensive care unit admission; 213 had changes > or = .3 mg/dL in serum creatinine within 48 hrs and/or urine output of < or = .5 mL/kg/hr for > 6 hrs. Detailed fluid challenge information was available for only 123 patients, who met acute kidney injury criteria, and three patients reversed after administration of > or = 500 mL of intravenous fluid and/or blood products. All patients whose creatinine increased > or = 50% also had increments > or = 0.3 mg/dL. The 120 patients with acute kidney injury were older (mean +/- SE: 69.3 +/- 1.7 vs. 62.9 +/- 1.3, p < .01), were more ill (Acute Physiology and Chronic Health Evaluation II score 18.7 +/- .6 vs. 13.3 +/- .4, p < .01), and had multiple comorbidities (two or more organs, 65% vs. 51.3%, p < .01) compared with those without acute kidney injury. The mortality rate of patients who met criteria for acute kidney injury was significantly higher than that of patients who did not have acute kidney injury (45.8 vs. 16.4%, p < .01). In multivariate logistic regression analyses, acute kidney injury was an independent predictor of mortality (adjusted odds ratio 3.7, 95% confidence interval 2.2-6.1). Acute kidney injury was a better predictor of in-hospital mortality than was Acute Physiology and Chronic Health Evaluation II score, advanced age, or presence of nonrenal organ failures. Median hospital stay was twice as long in patients with acute kidney injury (14 vs. 7 days, p < .01), and only patients with acute kidney injury required hemodialysis during hospitalization. The oliguria criterion of acute kidney injury did not affect the odds of in-hospital mortality. CONCLUSIONS: The Acute Kidney Injury Network definition of acute kidney injury predicts hospital mortality, need for renal replacement therapy, and prolonged hospital stay in critically ill patients. An increment of serum creatinine > or = 0.3 mg/dL in 48 hrs alone predicts clinical outcomes as well as the full Acute Kidney Injury Network definition.

Physician preferences for medical interventions in elderly patients.

PURPOSE: To identify factors influencing medical decision making in the elderly based on differences in age, cognition, and function. MEASUREMENTS: Physicians were given a clinical scenario and asked to select from three management options based on the patients' characteristics. RESULTS: Eighty-six percent would offer aggressive management to patients less than 85 years of age, whereas only 47.2% would offer similar care to those over 85 years of age (RR 0.5; 95% CI: 0.4-0.7). Physicians were less likely to offer aggressive management for patients with dementia (RR 0.2; 95% CI: 0.1-0.6), and for those requiring home assistance (RR: 0.2; 95% CI: 0.1-0.6) compared to those without dementia or functional limitations. CONCLUSION: Physicians are more likely to deny aggressive management to functionally active adults over 85 years of age, and to those with dementia or functional impairment irrespective of age.

A video depicting resuscitation did not impact upon patients' decision-making.

BACKGROUND: Previous studies have demonstrated that video of and scripted information about cardiopulmonary resuscitation (CPR) can be deployed during clinician-patient end-of-life discussions. Few studies, however, examine whether video adds to verbal information-sharing. We hypothesized that video augments script-only decision-making. METHODS: Patients aged >65 years admitted to hospital wards were randomized to receive evidence-based information ("script") vs. script plus video of simulated CPR and intubation. Patients' decisions registered in the hospital record, by hospital discharge were compared for the two groups. RESULTS: Fifty script-only intervention patients averaging 77.7 years were compared to 50 script+video patients with a mean age of 74.7 years. Eleven of 50 (22%) in each group declined CPR; and an additional three (script) vs. four (script+video) refused intubation for respiratory failure. There were no differences in sex, self-reported health trajectory, functional limitations, length of stay, or mortality associated with decisions. CONCLUSION: The rate at which verbally informed hospitalized elders opted out of resuscitation was not impacted by adding a video depiction of CPR.

Fluid balance and weaning outcomes.

OBJECTIVE: To examine the relationship of fluid balance and weaning outcomes. METHODS: We prospectively collected demographic, physiological, daily fluid balance (measured inputs minus outputs), and weaning data from 87 mechanically ventilated patients. PATIENTS: We examined 87 patients, a median age of 66 years, APACHE II of 22, and performed 205 breathing trials (BT); 38 patients (44%) were successfully extubated after their first BT with minimal or no pressure support. RESULTS: Positive fluid balance (inputs>outputs) in the 24, 48, and 72 h and cumulatively (from hospital admission) prior to weaning were significantly greater in weaning failures than successes. Both univariate and multivariate analyses, adjusted for duration of mechanical ventilation and presence of chronic obstructive pulmonary disease, showed negative cumulative fluid balance 24 h prior to BTs (OR=2.9) and cumulative fluid balance (OR=3.4) to be independently associated with first-day weaning success. Similar relationships were demonstrated when all weaning attempts were analyzed. Negative fluid balance was as predictive of weaning outcomes as f/V(t) (likelihood of success was 1.7 for patients with negative fluid balance 24 h prior to weaning and 1.2 for those with f/Vt<100 min-1 l-1). Although administration of diuretics was associated with more negative fluid balance, it was not independently associated with weaning outcomes. CONCLUSIONS: These data suggest that fluid balance, a potentially modifiable factor, is associated with weaning outcomes. A randomized study is required to determine whether diuresis to treat positive fluid balance expedites liberation from mechanical ventilation.

Benefits of comprehensive inpatient education and discharge planning combined with outpatient support in elderly patients with congestive heart failure.

Multidisciplinary disease management programs for congestive heart failure have been shown to substantially reduce readmission rates, resulting in a reduction of costs. These interventions, however, have typically included changes in medical management, making it difficult to quantitate the key elements of a successful program involving education, discharge planning, and transitional care in the outpatient setting. The investigators utilized an experienced cardiac nurse educator to coordinate a targeted inpatient congestive heart failure education program coupled with comprehensive discharge planning and immediate outpatient reinforcement through a coordinated nurse-driven home health care program. The comprehensive intervention resulted in a marked reduction in 6-month readmission rates, from 44.2% to 11.4% (p=0.01). The average total cost saving for each subject in the interventional group was $1541, based on the decreased utilization of both skilled nursing services and home health care during outpatient follow-up. The costs to implement an inpatient education program were negligible, at $158 per subject. There was no difference in discharge medications or medical management protocols that would have influenced these results.

Patients' understanding of advance directives and cardiopulmonary resuscitation.

OBJECTIVE: To describe understanding of end-of-life issues and compare characteristics of patients with and without advance directives. SETTING: A 325-bed community teaching hospital. MEASUREMENTS: Questionnaires were administered to all patients admitted to the medical-surgical wards. RESULTS: Of 755 patients admitted during the study period, 264 patients participated in the study, and 82 (31%) had living wills. Patients with living wills were more likely to be white, Protestant, and highly educated. Most (76%) created them with a lawyer or family member, whereas only 7% involved physicians. Although these patients were able to identify some components of cardiopulmonary resuscitation (CPR), few (19%) understood the prognosis after CPR. After explaining CPR, 37% of those with living wills did not want it, which was not stated in their directive or hospital record. If life-sustaining therapies were already started, 39% of these patients stated that they would not want CPR or mechanical ventilation if the likelihood of recovery was < or =10%. Patients without living wills either had not heard (18%) or did not know enough (51%) about them. After education, 5% did not want CPR, and 32% would terminate life-sustaining therapies if the likelihood of recovery was < or =10%. Seventy percent of these patients expressed interest in creating a living will. CONCLUSIONS: Patients with living wills understand poorly "life-sustaining therapies" and the implications of their advance directives. Most fail to involve physicians in creating directives. A significant number of those without living wills have end-of-life wishes that could be addressed by and appear open to the idea of creating advance directives.

Informed consent for medical procedures: local and national practices.

BACKGROUND: No studies have assessed whether clinicians obtain informed consent for invasive medical procedures, and there are no explicit national standards to guide the process. HYPOTHESIS: Informed consent practices are inconsistent for commonly performed invasive medical procedures. METHODS: A simple questionnaire was electronically mailed and/or faxed to training program directors of critical care medicine and internal medicine departments, and to ICU directors in the state of Connecticut. The questionnaire listed common invasive medical procedures and asked the respondents to check those for which practitioners routinely obtain informed consent in their hospital. RESULTS: The three samples, national intensivists (88 respondents), Connecticut intensivists (29 respondents), and national internists (56 respondents) demonstrated heterogeneity of consenting practices. The rate of obtaining consent for common vascular access procedures ranged from 20 to 90%. The rates of obtaining consent for Foley catheterization and nasogastric intubation were uniformly < 10%, and those for endoscopic procedures were > 90%. Separate consent (beyond the general consent to treat) was not uniformly obtained for the transfusion of blood products (range, 74 to 93%) and common diagnostic medical procedures (eg, thoracentesis, paracentesis, or lumbar puncture; range, 77 to 96%). Surgical intensivists reported that the obtaining of consent for invasive procedures was less routine compared to medical intensivists. Lower rates of consent were noted by those respondents who used a "blanket" consent form, which was signed at the time of hospital admission, to cover subsequent procedures. CONCLUSIONS: In this relatively small sample, there was no uniform practice of informed consent for commonly performed invasive medical procedures. Consent was routinely obtained for GI endoscopy, bronchoscopy, and medical research, and was not obtained for Foley catheterization and nasogastric intubation. The obtaining of consent for vascular cannulation and diagnostic procedures was not routine in the ICUs of a substantial number of respondents. Explicit standards that delineate specifically which procedures require consent may be required to assure more uniform practices.

Cough peak flows and extubation outcomes.

BACKGROUND: Semiobjective methods of quantifying cough strength and endotracheal secretions have been demonstrated to predict extubation outcomes of patients who have passed a spontaneous breathing trial (SBT). HYPOTHESIS: Cough strength, measured by voluntary cough peak expiratory flow (PEF), and endotracheal secretions, measured volumetrically, predict extubation outcomes of patients who have passed an SBT. PATIENT POPULATION: Critically ill patients admitted to the medical ICU of a 300-bed community teaching hospital. METHODS: All patients who passed an SBT and were about to be extubated were studied. The best of three cough attempts, measured with an in-line spirometer, and the average hourly rate of suctioned secretions prior to extubation were recorded with other weaning parameters and demographic data. RESULTS: Ninety-five patients were studied before and after 115 extubations. There were 13 unsuccessful extubations. There were no differences in age, gender, duration of intubation, or APACHE (acute physiology and chronic health evaluation) II scores between successful and unsuccessful extubations. The magnitude of endotracheal secretions was not associated with outcomes. The PEF of patients with unsuccessful extubations was significantly lower than that of those with successful extubations (64.2 +/- 6.8 L/min vs 81.9 +/- 2.7 L/min, p = 0.03). Patients with unsuccessful extubations stayed longer in the ICU than those with successful extubations (11.7 +/- 2.1 days vs 5.3 +/- 0.4 days, p = 0.009). Those with PEF

Anticoagulation in hospitalized patients with renal insufficiency: a comparison of bleeding rates with unfractionated heparin vs enoxaparin.

OBJECTIVES: To compare the rates of bleeding complications in patients with renal insufficiency who receive anticoagulation therapy with the full therapeutic dose, unfractionated heparin (UFH), or with twice-daily enoxaparin. SETTING: A 325-bed community teaching hospital. STUDY TYPE: Retrospective cohort study. METHODS: The medical records of all patients with renal insufficiency who received anticoagulation therapy with UFH or enoxaparin during a 13-month period were reviewed for the occurrence of major and minor bleeding. Incidence rates were computed per 1,000-person days of anticoagulation therapy. Comparisons were made across categories of renal insufficiency and other potential confounders. RESULTS: A total of 620 patients with estimated glomerular filtration rates of < 60 mL/min were studied. Of these, 331 received anticoagulation therapy with UFH, 250 with enoxaparin, and 39 with both (not simultaneously). The major bleeding rates were 26.3 per 1,000 person-days for UFH and 20.7 per 1,000 person-days for enoxaparin. Major bleeding complications were similarly increased for both UFH and enoxaparin therapy across categories of worsening renal insufficiency. Patients with severe renal insufficiency while receiving enoxaparin had a 154% excess incidence of minor bleeding compared to those receiving UFH (incidence ratio, 2.54; 95% confidence interval, 1.01 to 6.36). Worsening renal insufficiency, female gender, and prolonged duration of anticoagulation therapy emerged as the main determinants for bleeding complications. CONCLUSION: Both the twice-daily enoxaparin and UFH regimens are associated with comparable increases in major bleeding complications in patients with renal dysfunction receiving full-dose anticoagulation therapy. Both agents should be used with caution in anticoagulation therapy for patients with renal insufficiency.

Neurologic status, cough, secretions and extubation outcomes.

OBJECTIVE: To determine the degree to which neurologic function, cough peak flows and quantity of endotracheal secretions affected the extubation outcomes of patients who had passed a trial of spontaneous breathing (SBT). DESIGN: Prospective observational study. SETTING: The medical intensive care unit of a 325-bed teaching hospital. MEASUREMENTS AND MAIN RESULTS: Cough peak flow (CPF), endotracheal secretions and ability to complete four simple tasks were measured just before extubation in patients who had passed a SBT. Eighty-eight patients were studied; 14 failed their first trials of extubation. The CPF of patients who failed was lower than that of those who had a successful extubation (58.1+/-4.6 l/min vs 79.7+/-4.1 l/min, p=0.03) and those with CPF 60 l/min or less were nearly five times as likely to fail extubation compared to those with CPF higher than 60 l/min (risk ratio [RR]=4.8; 95% CI=1.4-16.2). Patients with secretions of more than 2.5 ml/h were three times as likely to fail (RR=3.0; 95% CI=1.0-8.8) as those with fewer secretions. Patients who were unable to complete four simple tasks (i.e. open eyes, follow with eyes, grasp hand, stick out tongue) were more than four times as likely to fail as those who completed the four commands (RR=4.3; 95% CI=1.8-10.4). There was synergistic interaction between these risk factors. The failure rate was 100% for patients with all three risk factors compared to 3% for those with no risk factors (RR=23.2; 95% CI=3.2-167.2). The presence of any two of the above risk factors had a sensitivity of 71 and specificity of 81% in predicting extubation failure. Patients who failed a trial of extubation were 3.8 times as likely to have any two risk factors compared to those who were successful. CONCLUSIONS: These simple, reproducible methods may provide a clinically useful approach to guiding the extubation of patients who have passed a SBT.

Predictors and consequences of pneumonia in critically ill patients with stroke.

OBJECTIVE: Ascertain the incidence, predictors and consequences of early (within 48 hours of admission) and nosocomial pneumonia among critically ill patients with stroke. METHODS: Medical records of critically ill patients with acute stroke were reviewed. Predictors and consequences of pneumonia were determined with analysis of variance. RESULTS: 55 patients, aged 33 to 91 (median 74) years, were admitted. The stroke was located at the brainstem in 14 (26.4%) patients. Nine patients (16.4%) had early pneumonia and additional 17 patients (30.9%) developed nosocomial pneumonia. Patients with brain-stem stroke were more likely to develop early pneumonia (p =.04). Nosocomial pneumonia incidence was higher in patients who failed swallowing evaluation (RR = 6.3, 95% CI: 0.9-43.0) and in those who were intubated (58.6% v 0%, p =.00008). Also, nosocomial pneumonia was associated with longer duration of mechanical ventilation and prolonged hospital stay. Nineteen patients (34.5%) died at the hospital. They were more likely to be older (median 77 versus 69 years, p =.03) with higher admission acuity of illness. CONCLUSION: Pneumonia complicated stroke in 47% of critically ill patients and adversely impacted the duration of mechanical ventilation and overall length of hospital stay. Aggressive preventive measures are needed to reduce pneumonia occurrence in stroke patients.

Propofol infusion is associated with a higher rapid shallow breathing index in patients preparing to wean from mechanical ventilation.

OBJECTIVE: To determine whether propofol affects spontaneous breathing patterns in critically ill patients recovering from respiratory failure during initial attempts at liberation from mechanical ventilation. DESIGN: Observational cohort study. PATIENTS: Ten critically ill patients in the medical intensive care unit of a 300-bed community teaching hospital. MEASUREMENTS: Demographic and physiologic variables, including respiratory frequency and minute volume, were recorded while patients breathed on continuous positive airway pressure (of 5 cm H(2)O) during and 20-30 min after cessation of propofol infusion. The ratio of respiratory frequency to tidal volume (rapid shallow breathing index or RSBI) was computed for both sets of measurements and values measured during and after propofol infusion were compared. RESULTS: The mean (+/- SEM) age was 54.0 +/- 5.2 years and the mean (+/- SEM) APACHE II (Acute Physiology and Chronic Health Evaluation) score was 18.4 +/- 2.0. During propofol infusion, patients breathed with a significantly lower tidal volume (0.245 vs 0.342 L, p = 0.006), higher RSBI (155.6 vs 114.8 breaths/min/L, p = 0.004), and tended to breathe more rapidly (34.3 vs 31.7 breaths/min, p = 0.18) than at 20-30 min after stopping propofol infusion. Three of 10 patients had RSBIs that were unfavorable (> 105 breaths/min/L) for weaning while on propofol but that became favorable (< 105 breaths/min/L) 20-30 min following cessation of propofol. The weight-adjusted dose of propofol was not correlated with the changes in any of the variables. CONCLUSIONS: Propofol causes changes in breathing pattern that could lead a caregiver to erroneously conclude that a patient is not ready to begin spontaneous breathing trials. Since this effect has also been noted following benzodiazepine infusion, the clinician should consider the patient's "sedation history" when using RSBI to guide weaning decisions.

The effect of arterial blood gas values on extubation decisions.

BACKGROUND: No studies have examined the clinical utility of arterial blood gas (ABG) values during spontaneous breathing trials (SBTs) for making extubation decisions. Nonetheless many intensive care units measure ABGs during an SBT to determine, in conjunction with other data, whether the SBT was successful. OBJECTIVE: Determine how often ABG values change extubation decisions. METHODS: Each patient was assessed at the bedside by one of 3 critical care attending physicians. Each assessment was made at the end of the SBT in which ABGs were obtained with the expectation of extubation. When a nurse, respiratory therapist, or resident was available, he or she also simultaneously and independently evaluated the patient and then reassessed with the ABG values. Physiologic data were recorded before and during the SBT, as the attending physician performed the bedside assessment. RESULTS: Eighty-three patients were studied during 100 SBTs. Heart rate, respiratory rate, and mean blood pressure increased. Blood oxygen saturation (measured via pulse oximetry [F(IO)(2)]) and the P(aO)(2)/F(IO)(2) ratio decreased significantly during SBTs. Concordant clinical and ABG assessment (to attempt a trial of extubation) led to extubation in 86 patients, 76 of whom remained extubated after 72 hours. Following 14 of the SBTs, the patients were not extubated. Seven of these were judged by the attending physicians to fail both clinically and following review of ABG values. Seven were judged successful clinically, but the patients were not extubated because the attending physician thought the ABG values were unfavorable. Bedside nurses, who assessed 72 SBTs, had 1 case in which the ABG values changed their extubation opinion. Resident-trainees assessed 76 cases and had 5 changes of opinion based on ABG values. Respiratory therapists assessed 77 patients and had 4 such cases. The average changes in heart rate and blood pressure of patients not extubated were double those of extubated patients, but there were no significant differences in respiratory rate or P(aO)(2)/F(IO)(2) ratio between those groups. Ten patients (11.6%) were extubated based on the attending physician's decision but required re-intubation within 72 hours. CONCLUSION: These data suggest that ABG values did not change extubation decisions in 93% of cases. However, in 7 cases the ABG values changed the extubation decision. If even a few of those cases would have failed extubation without knowledge of the ABG values, the increased patient risk and cost associated with failed extubation would more than offset the relatively small cost of collecting ABG values from all patients who undergo SBT.