A comparison of initial monotherapy with norepinephrine versus vasopressin for resuscitation in septic shock

BACKGROUND

Early goal-directed therapy is a time-sensitive therapeutic algorithm with a tiered approach to target hypoperfusion and cardiovascular collapse within the first 6 hours of septic shock. The Surviving Sepsis Campaign guidelines recommend norepinephrine or dopamine as the initial vasoactive agent for resuscitation in septic shock, reserving the administration of vasopressin as adjunctive therapy.

OBJECTIVE

To determine whether vasopressin was noninferior to norepinephrine as the initial vasopressor to achieve a mean arterial pressure (MAP) goal in the first 6 hours of shock onset.

METHODS

This retrospective cohort study evaluated adults who received monotherapy with either norepinephrine or vasopressin as initial vasoactive therapy for the management of septic shock. Patients were excluded if the treatment arm was not monotherapy, if they were admitted to a cardiology or cardiothoracic surgery service, or if they lacked a comparator-based 1:1 frequency matching.

RESULTS

A total of 130 patients were included, 65 in each treatment arm. The proportion of patients who achieved a goal MAP in the vasopressin group was 63% (95% CI 51%-75%) and was 67.7% (95% CI 56%-79%) in the norepinephrine group. This observed difference between goal MAP attainment did not exceed the predefined noninferiority margin of -25% (CI for 4.7% difference -21.2% to 12%), suggesting noninferiority of vasopressin. No significant difference was identified between vasopressin and norepinephrine for final mean (SD) MAP achieved (75 [9.6] and 76.0 [8.2] mm Hg, respectively; p = 0.06) or the mean total change from baseline MAP to goal (14.1 [8.4] and 15.1 [9.1] mm Hg, respectively; p = 0.6).

CONCLUSIONS

Vasopressin was noninferior to norepinephrine for the achievement of a MAP goal in the first 6 hours from onset of septic shock. Further prospective analysis is warranted; however, the results are useful for consideration of alternative vasopressors in the setting of drug shortages.

Recommendations to limit life support: a national survey of critical care physicians

RATIONALE

There is debate about whether physicians should routinely provide patient surrogates with recommendations about limiting life support.

OBJECTIVES

To explore physicians' self-reported practices and attitudes.

METHODS

A cross-sectional, stratified survey of 1,000 randomly selected US critical care physicians was mailed. We included a vignette to experimentally examine how surrogate desire for a recommendation and physician agreement with the surrogate modified whether physicians would provide a recommendation.

MEASUREMENTS AND MAIN RESULTS

Proportion of respondents reporting they routinely provide surrogates with a recommendation and how responses varied based on vignette characteristics. A total of 608 (66%) of 922 eligible physicians participated. Approximately one (22%) in five reported always providing surrogates with a recommendation, whereas 1 (11%) in 10 reported rarely or never doing so. Almost all respondents reported comfort making recommendations (92%) and viewed them as appropriate (93%). Most also viewed recommendations as a critical care physician's duty (87%) and did not view them as unduly influential (80%). Approximately two-fifths (41%) believed recommendations were only appropriate if sought by surrogates. In response to the vignettes, nearly all respondents (91%) provided a recommendation when the surrogate requested a recommendation and the physician agreed with the surrogate's likely decision. Physicians were less likely to provide an unwanted recommendation, both when physicians agreed (29%) and disagreed with the surrogate's likely decision (44%).

CONCLUSIONS

There is substantial variation among physicians' self-reported use of recommendations to surrogates of critically ill adults. Surrogates' desires for recommendations and physicians' agreement with surrogates' likely decisions may have important influence on whether recommendations are provided.

Relationships among performance, residual feed intake, and product quality of progeny from Red Angus sires divergent for maintenance energy EPD

Energy expenditure is a physiological process that may be closely associated with residual feed intake (RFI). The maintenance energy (ME(M)) EPD was developed by the Red Angus Association of America (RAAA) and is used as an indicator of energy expenditure. The objectives of this study were to evaluate and quantify the following relationships using progeny of Red Angus (RA) sires divergent for ME(M) EPD: 1) postweaning RFI and finishing phase feed efficiency (FE), 2) postweaning RFI and end-product quality, and 3) postweaning RFI and sire ME(M) EPD. A total of 12 RA sires divergent for ME(M) EPD were chosen using the RAAA-generated ME(M) EPD values and were partitioned into 2 groups: high ME(M) EPD (≥4 Mcal/mo) and low ME(M) EPD (<4 Mcal/mo), based on the breed average of 4 Mcal/mo. Commercial crossbred cows were inseminated to produce 3 cohorts of progeny, which were tested for postweaning RFI (cohorts 1, 2, and 3) and finishing phase FE (cohorts 1 and 3). Results indicate that postweaning RFI and finishing phase FE of steer progeny tended to be positively correlated (r = 0.38; P = 0.06) in cohort 1 and were positively correlated (r = 0.50; P = 0.001) in cohort 3. In addition, postweaning RFI was not phenotypically correlated (P > 0.05) with any carcass traits or end-product quality measurements. Sire ME(M) EPD was phenotypically correlated (P < 0.05) with carcass traits in cohort 1 (HCW, LM area, KPH, fat thickness, and yield grade) and cohort 2 (KPH and fat thickness). Since variation in measured LM area was not explained by the genetic potential of rib eye area EPD, and therefore, the observed correlation between sire ME(M) EPD and measured LM area may suggest an association between ME(M) EPD and LM area. A correlation (r = 0.24; P = 0.02) was observed between postweaning RFI and ultrasound intramuscular fat percentage in cohort 2 but was not detected in cohorts 1 or 3. In addition, no phenotypic relationship was observed (P > 0.05) between progeny postweaning RFI and sire ME(M) EPD. Therefore, results suggest 1) RFI measured during the postweaning growth phase is indicative of FE status in the finishing phase, 2) neither RFI nor sire ME(M) EPD negatively affected carcass or end-product quality, and 3) RFI and sire ME(M) EPD are not phenotypically associated.

Temporal disorganization of circadian rhythmicity and sleep-wake regulation in mechanically ventilated patients receiving continuous intravenous sedation

OBJECTIVES

Sleep is regulated by circadian and homeostatic processes and is highly organized temporally. Our study was designed to determine whether this organization is preserved in patients receiving mechanical ventilation (MV) and intravenous sedation.

DESIGN

Observational study.

SETTING

Academic medical intensive care unit.

PATIENTS

Critically ill patients receiving MV and intravenous sedation.

METHODS

Continuous polysomnography (PSG) was initiated an average of 2.0 (1.0, 3.0) days after ICU admission and continued ≥ 36 h or until the patient was extubated. Sleep staging and power spectral analysis were performed using standard approaches. We also calculated the electroencephalography spectral edge frequency 95% SEF₉₅, a parameter that is normally higher during wakefulness than during sleep. Circadian rhythmicity was assessed in 16 subjects through the measurement of aMT6s in urine samples collected hourly for 24-48 hours. Light intensity at the head of the bed was measured continuously.

MEASUREMENTS AND RESULTS

We analyzed 819.7 h of PSG recordings from 21 subjects. REM sleep was identified in only 2/21 subjects. Slow wave activity lacked the normal diurnal and ultradian periodicity and homeostatic decline found in healthy adults. In nearly all patients, SEF₉₅ was consistently low without evidence of diurnal rhythmicity (median 6.3 [5.3, 7.8] Hz, n = 18). A circadian rhythm of aMT6s excretion was present in most (13/16, 81.3%) patients, but only 4 subjects had normal timing. Comparison of the SEF₉₅ during the melatonin-based biological night and day revealed no difference between the 2 periods (P = 0.64).

CONCLUSIONS

The circadian rhythms and PSG of patients receiving mechanical ventilation and intravenous sedation exhibit pronounced temporal disorganization. The finding that most subjects exhibited preserved, but phase delayed, excretion of aMT6s suggests that the circadian pacemaker of such patients may be free-running.

Early cardiac arrest in patients hospitalized with pneumonia: a report from the American Heart Association's Get With The Guidelines-Resuscitation Program

BACKGROUND

Pneumonia is the leading infectious cause of death. Early deterioration and death commonly result from progressive sepsis, shock, respiratory failure, and cardiac complications. Recent data suggest that cardiac arrest may also be common, yet few previous studies have addressed this. Accordingly, we sought to characterize early cardiac arrest in patients who are hospitalized with coexisting pneumonia.

METHODS

We performed a retrospective analysis of a multicenter cardiac arrest database, with data from > 500 North American hospitals. We included in-hospital cardiac arrest events that occurred in community-dwelling adults with pneumonia within the first 72 h after hospital admission. We compared patient and event characteristics for patients with and without pneumonia. For patients with pneumonia, we also compared events according to event location.

RESULTS

We identified 4,453 episodes of early cardiac arrest in patients who were hospitalized with pneumonia. Among patients with preexisting pneumonia, only 36.5% were receiving mechanical ventilation and only 33.3% were receiving infusions of vasoactive drugs prior to cardiac arrest. Only 52.3% of patients on the ward were receiving ECG monitoring prior to cardiac arrest. Shockable rhythms were uncommon in all patients with pneumonia (ventricular tachycardia or fibrillation, 14.8%). Patients on the ward were significantly older than patients in the ICU.

CONCLUSIONS

In patients with preexisting pneumonia, cardiac arrest may occur in the absence of preceding shock or respiratory failure. Physicians should be alert to the possibility of abrupt cardiopulmonary collapse, and future studies should address this possibility. The mechanism may involve myocardial ischemia, a maladaptive response to hypoxia, sepsis-related cardiomyopathy, or other phenomena.

Artificial insemination at 56 h after intravaginal progesterone device removal improved AI pregnancy rate in beef heifers synchronized with five-day CO-Synch + controlled internal drug release (CIDR) protocol

The objective was to determine whether timed artificial insemination (TAI) 56 h after removal of a Controlled Internal Drug Release (CIDR, 1.38 g of progesterone) insert would improve AI pregnancy rate in beef heifers compared to TAI 72 h after CIDR insert removal in a 5-days CO-Synch + CIDR protocol. Angus cross beef heifers (n = 1098) at nine locations [WA (5 locations; n = 634), ID (2 locations; n = 211), VA (one location; n = 193) and WY (one location; n = 60)] were included in this study. All heifers were given a body condition score (BCS; 1-emaciated; 9-obese), and received a CIDR insert and 100 μg of gonadorelin hydrochloride (GnRH) on Day 0. The CIDR insert was removed and two doses of 25 mg of dinoprost (PGF(2α)) were given, first dose at CIDR insert removal and second dose 6 h later, on Day 5. A subset of heifers (n = 629) received an estrus detector aid at CIDR removal. After CIDR removal, heifers were observed thrice daily for estrus and estrus detector aid status until they were inseminated. Within farm, heifers were randomly allocated to two groups and were inseminated either at 56 h (n = 554) or at 72 h (n = 544) after CIDR removal. All heifers were given 100 μg of GnRH at AI. Insemination 56 h after CIDR insert removal improved AI pregnancy rate compared to insemination 72 h (66.2 vs. 55.9%; P < 0.001; 1 - β = 0.94). Locations, BCS categories (≤ 6 vs. > 6) and location by treatment and BCS by treatment interactions did not influence AI pregnancy rate (P > 0.1). The AI pregnancy rates for heifers with BCS ≤ 6 and > 6 were 61.8 and 60.1%, respectively (P > 0.1). The AI pregnancy rates among locations varied from 54.9 to 69.2% (P > 0.1). The AI pregnancy rate for heifers observed in estrus at or before AI was not different compared to heifers not observed in estrus [(65.4% (302/462) vs. 52.7% (88/167); P > 0.05)]. In conclusion, heifers inseminated 56 h after CIDR insert removal in a 5-days CO-Synch + CIDR protocol had, on average, 10.3% higher AI pregnancy rate compared to heifers inseminated 72 h after CIDR insert removal.

Predicting cardiac arrest on the wards: a nested case-control study

BACKGROUND

Current rapid response team activation criteria were not statistically derived using ward vital signs, and the best vital sign predictors of cardiac arrest (CA) have not been determined. In addition, it is unknown when vital signs begin to accurately detect this event prior to CA.

METHODS

We conducted a nested case-control study of 88 patients experiencing CA on the wards of a university hospital between November 2008 and January 2011, matched 1:4 to 352 control subjects residing on the same ward at the same time as the case CA. Vital signs and Modified Early Warning Scores (MEWS) were compared on admission and during the 48 h preceding CA.

RESULTS

Case patients were older (64 ± 16 years vs 58 ± 18 years; P = .002) and more likely to have had a prior ICU admission than control subjects (41% vs 24%; P = .001), but had similar admission MEWS (2.2 ± 1.3 vs 2.0 ± 1.3; P = .28). In the 48 h preceding CA, maximum MEWS was the best predictor (area under the receiver operating characteristic curve [AUC] 0.77; 95% CI, 0.71-0.82), followed by maximum respiratory rate (AUC 0.72; 95% CI, 0.65-0.78), maximum heart rate (AUC 0.68; 95% CI, 0.61-0.74), maximum pulse pressure index (AUC 0.61; 95% CI, 0.54-0.68), and minimum diastolic BP (AUC 0.60; 95% CI, 0.53-0.67). By 48 h prior to CA, the MEWS was higher in cases (P = .005), with increasing disparity leading up to the event.

CONCLUSIONS

The MEWS was significantly different between patients experiencing CA and control patients by 48 h prior to the event, but includes poor predictors of CA such as temperature and omits significant predictors such as diastolic BP and pulse pressure index.

Patient-related factors associated with hospital discharge to a care facility after critical illness

BACKGROUND

Many critically ill patients are transferred to other care facilities instead of to home at hospital discharge.

OBJECTIVE

To identify patient-related factors associated with hospital discharge to a care facility after critical illness and to estimate the magnitude of risk associated with each factor.

METHODS

Retrospective cohort study of 548 survivors of critical illness in a medical intensive care unit. Multivariable logistic regression was used to identify independent risk factors for discharge to a care facility. Only the first 72 hours of intensive care were analyzed.

RESULTS

Approximately one-quarter of the survivors of critical illness were discharged to a care facility instead of to home. This event occurred more commonly in older patients, even after adjustment for severity of illness and comorbid conditions (odds ratio [OR] 1.8 for patients ≥ 65 years of age vs patients < 65 years; 95% confidence interval [CI], 1.1-3.1; P = .02). The risk was greatest for patients who received mechanical ventilation (OR, 3.4; 95% CI, 2.0-5.8; P < .001) or had hospitalizations characterized by severe cognitive dysfunction (OR, 8.1; 95% CI, 1.3-50.6; P = .02) or poor strength and/or mobility (OR, 31.7; 95% CI, 6.4-157.3; P < .001). The model showed good discrimination (area under the curve, 0.82; 95% CI, 0.77-0.86).

CONCLUSION

The model, which did not include baseline function or social variables, provided good discrimination between patients discharged to a care facility after critical illness and patients discharged to home. These results suggest that future research should focus on the debilitating effects of respiratory failure and on conditions with cognitive and neuromuscular sequelae.

Multi-state Beef Reproduction Task Force provides science-based recommendations for the application of reproductive technologies

Since its formation, the Beef Reproduction Task Force (BRTF) has worked to enhance productivity and profitability of US beef herds by integrating research and extension efforts with the intent of more effectively transferring the use of reproductive technologies to the field. A key early step was to coordinate efforts in identifying effective breeding management protocols for beef cattle and to clarify their associated acronyms. A short list of recommended protocols and their acronyms for synchronization of estrus and ovulation in beef cattle was developed based on results from peer-reviewed, published research and a comprehensive review of data collected from the field. The list of recommended protocols was developed by the BRTF in cooperation with veterinarians and cattle AI industries. These protocols and their acronyms are presented uniformly in all of the major AI sire directories and are available online at http://www.beefrepro.info. Protocol updates are made annually to incorporate the most recent research findings related to estrous cycle control in beef cattle. The Estrus Synchronization Planner, a software program developed in cooperation with the Iowa Beef Center, now reflects these same recommendations. Beginning in 2002, the BRTF hosted and presented 11 educational workshops to more than 1,900 attendees in key cow-calf states. These Applied Reproductive Strategies in Beef Cattle workshops targeted beef producers, AI industry personnel, veterinarians, allied industry representatives, and academicians. A national media sponsor provided online coverage of the last 3 workshops at http://www.appliedreprostrategies.com. A postmeeting evaluation, developed to assess application of information from 2 recent workshops, was returned by 55% of those contacted (n = 150). Attendees averaged 16 (± 13.4 SD) yr of AI experience, and 80% of respondents represented more than 100 cows. Respondents were asked to estimate the value of AI-sired calves compared with natural-service-sired calves to their operation on a per-animal-marketed basis, and 17 and 31% responded $50 to $100 per animal and more than $100 per animal, respectively. As a result of what was learned at these conferences, 78% of respondents were better able to troubleshoot management-related issues, 60% made alterations to a protocol they had been using, and 35% of the respondents indicated they changed to a different estrus synchronization protocol.

Thirty years of critical care medicine

Critical care medicine is a relatively young but rapidly evolving specialty. On the occasion of the 30th International Symposium on Intensive Care and Emergency Medicine, we put together some thoughts from a few of the leaders in critical care who have been actively involved in this field over the years. Looking back over the last 30 years, we reflect on areas in which, despite large amounts of research and technological and scientific advances, no major therapeutic breakthroughs have been made. We then look at the process of care and realize that, here, huge progress has been made. Lastly, we suggest how critical care medicine will continue to evolve for the better over the next 30 years.

Early physical and occupational therapy in mechanically ventilated, critically ill patients: a randomised controlled trial

BACKGROUND

Long-term complications of critical illness include intensive care unit (ICU)-acquired weakness and neuropsychiatric disease. Immobilisation secondary to sedation might potentiate these problems. We assessed the efficacy of combining daily interruption of sedation with physical and occupational therapy on functional outcomes in patients receiving mechanical ventilation in intensive care.

METHODS

Sedated adults (>/=18 years of age) in the ICU who had been on mechanical ventilation for less than 72 h, were expected to continue for at least 24 h, and who met criteria for baseline functional independence were eligible for enrolment in this randomised controlled trial at two university hospitals. We randomly assigned 104 patients by computer-generated, permuted block randomisation to early exercise and mobilisation (physical and occupational therapy) during periods of daily interruption of sedation (intervention; n=49) or to daily interruption of sedation with therapy as ordered by the primary care team (control; n=55). The primary endpoint-the number of patients returning to independent functional status at hospital discharge-was defined as the ability to perform six activities of daily living and the ability to walk independently. Therapists who undertook patient assessments were blinded to treatment assignment. Secondary endpoints included duration of delirium and ventilator-free days during the first 28 days of hospital stay. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00322010.

FINDINGS

All 104 patients were included in the analysis. Return to independent functional status at hospital discharge occurred in 29 (59%) patients in the intervention group compared with 19 (35%) patients in the control group (p=0.02; odds ratio 2.7 [95% CI 1.2-6.1]). Patients in the intervention group had shorter duration of delirium (median 2.0 days, IQR 0.0-6.0 vs 4.0 days, 2.0-8.0; p=0.02), and more ventilator-free days (23.5 days, 7.4-25.6 vs 21.1 days, 0.0-23.8; p=0.05) during the 28-day follow-up period than did controls. There was one serious adverse event in 498 therapy sessions (desaturation less than 80%). Discontinuation of therapy as a result of patient instability occurred in 19 (4%) of all sessions, most commonly for perceived patient-ventilator asynchrony.

INTERPRETATION

A strategy for whole-body rehabilitation-consisting of interruption of sedation and physical and occupational therapy in the earliest days of critical illness-was safe and well tolerated, and resulted in better functional outcomes at hospital discharge, a shorter duration of delirium, and more ventilator-free days compared with standard care.

FUNDING

None.

Fixed-time AI pregnancy rate following insemination with frozen-thawed or fresh-extended semen in progesterone supplemented CO-Synch protocol in beef cows

The objective of this study was to compare fixed-time AI pregnancy rate in Angus crossbred beef cows inseminated with frozen-thawed or fresh-extended semen. Two ejaculates from each of two Angus bulls were collected by artificial vagina and pooled for each bull. The pooled semen from each bull was divided into two aliquots; Aliquot 1 was extended using Caprogen (LIC, Hamilton, New Zealand) to a concentration of 3 x 10(6)sperm/straw and Aliquot 2 was extended using egg-yolk-glycerol extender to a concentration of 20 x 10(6)sperm/straw. Semen extended with Caprogen was maintained at ambient temperature and semen extended with egg-yolk-glycerol extender was frozen and maintained at -196 degrees C until insemination. In each of two breeding seasons (Fall 2007 and Spring 2008), Angus-crossbeef cows (N=1455) at 12 locations were randomly assigned within location to semen type [Fresh (N=736) vs. Frozen (N=719)] and sire [1 (N=731) vs. 2 (N=724)]. All cows were synchronized with 100 microg of GnRH im and a progesterone Controlled Internal Drug Release insert (CIDR) on Day 0, and on Day 7, 25mg of PGF2(alpha) im and CIDR removal. All cows received 100 microg of GnRH im and were inseminated at a fixed-time on Day 10, 66 h after CIDR removal. Timed-AI pregnancy rates were influenced by season (P<0.05), cows detected in estrus prior to and at AI (P<0.001), and dam age (P<0.01). Pregnancy rates were not affected by semen type (Fresh=51.5% vs. Frozen=50.4%; P=0.66) and there were no significant interactions of semen type by estrus expression, semen type by sire, or semen type by season (P>0.1). In conclusion, commercial beef cows inseminated with fresh-extended semen (3 x 10(6)sperm/straw) yielded comparable pregnancy rates to conventional frozen-thawed semen in a progesterone supplemented, CO-Synch fixed-time AI synchronization protocol and may provide an alternate to frozen semen for more efficient utilization of superior genetics.

Sire effect on the pregnancy outcome in beef cows synchronized with progesterone based Ovsynch and CO-Synch protocols

The objective was to determine the sire effect on the pregnancy outcome in beef cows in which stage of estrus was synchronized with progesterone based fixed-time artificial insemination (AI) protocols. Three Angus sires with more than 300 breedings were evaluated for differences in pregnancy outcome from 1868 inseminations. Angus cross beef cows (N=1868) were synchronized with Ovsynch-CIDR or CO-Synch-CIDR protocols for fixed-time AI. Cows in both groups that showed estrus on day 9 before 1500 h were designated to Selectsynch-CIDR group and were inseminated according to AM-PM rule. Results indicated that Sire 2 had lower fixed-time AI pregnancy rate compared to Sire 3 (48.1% versus 58.7%; P=0.01). Significant sirexsynchronization program and sirexlocation interactions were observed for fixed-time AI (P<0.05). Sire 2 had a lesser fixed-time AI pregnancy in both Ovsynch-CIDR and CO-Synch-CIDR groups compared to Sire 3. In two of four locations, Sire 2 had a lesser fixed-time pregnancy rate compared to Sire 3. No sire differences were observed in AI pregnancy for cows in Selectsynch-CIDR group. In conclusion, evidence in this study suggest that there are differences in sire fertility when they were used in fixed-time AI protocols, possibly due to the sire differences in sperm capacitation process. Further studies are needed to investigate association of the sire differences in fixed-time AI protocols with sire differences in the sperm capacitation process.

Diagnostic utility of B-type natriuretic peptide in critically ill patients with pulmonary edema: a prospective cohort study

Introduction

Distinguishing pulmonary edema due to acute lung injury (ALI) or the acute respiratory distress syndrome (ARDS) from hydrostatic or cardiogenic edema is challenging in critically ill patients. B-type natriuretic peptide (BNP) can effectively identify congestive heart failure in the emergency room setting but, despite increasing use, its diagnostic utility has not been validated in the intensive care unit (ICU).

Methods

We performed a prospective, blinded cohort study in the medical and surgical ICUs at the University of Chicago Hospitals. Patients were eligible if they were admitted to the ICU with respiratory distress, bilateral pulmonary edema and a central venous catheter suggesting either high-pressure (cardiogenic) or low-pressure (ALI/ARDS) pulmonary edema. BNP levels were measured within 48 hours of ICU admission and development of pulmonary edema and onward up to three consecutive days. All levels were drawn simultaneously with the measurement of right atrial or pulmonary artery wedge pressure. The etiology of pulmonary edema – cardiogenic or ALI/ARDS – was determined by three intensivists blinded to BNP levels.

Results

We enrolled a total of 54 patients (33 with ALI/ARDS and 21 with cardiogenic edema). BNP levels were lower in patients with ALI/ARDS than in those with cardiogenic edema (496 ± 439 versus 747 ± 476 pg/ml, P = 0.05). At an accepted cutoff of 100 pg/ml, specificity for the diagnosis of ALI/ARDS was high (95.2%) but sensitivity was poor (27.3%). Cutoffs at higher BNP levels improved sensitivity at considerable cost to specificity. Invasive measures of filling pressures correlated poorly with initial BNP levels and subsequent day BNP values fluctuated unpredictably and without correlation with hemodynamic changes and net fluid balance.

Conclusion

BNP levels drawn within 48 hours of admission to the ICU do not reliably distinguish ALI/ARDS from cardiogenic edema, do not correlate with invasive hemodynamic measurements, and do not track predictably with changes in volume status on consecutive daily measurements.

Efficacy and safety of a paired sedation and ventilator weaning protocol for mechanically ventilated patients in intensive care (Awakening and Breathing Controlled trial): a randomised controlled trial

BACKGROUND

Approaches to removal of sedation and mechanical ventilation for critically ill patients vary widely. Our aim was to assess a protocol that paired spontaneous awakening trials (SATs)-ie, daily interruption of sedatives-with spontaneous breathing trials (SBTs).

METHODS

In four tertiary-care hospitals, we randomly assigned 336 mechanically ventilated patients in intensive care to management with a daily SAT followed by an SBT (intervention group; n=168) or with sedation per usual care plus a daily SBT (control group; n=168). The primary endpoint was time breathing without assistance. Data were analysed by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00097630.

FINDINGS

One patient in the intervention group did not begin their assigned treatment protocol because of withdrawal of consent and thus was excluded from analyses and lost to follow-up. Seven patients in the control group discontinued their assigned protocol, and two of these patients were lost to follow-up. Patients in the intervention group spent more days breathing without assistance during the 28-day study period than did those in the control group (14.7 days vs 11.6 days; mean difference 3.1 days, 95% CI 0.7 to 5.6; p=0.02) and were discharged from intensive care (median time in intensive care 9.1 days vs 12.9 days; p=0.01) and the hospital earlier (median time in the hospital 14.9 days vs 19.2 days; p=0.04). More patients in the intervention group self-extubated than in the control group (16 patients vs six patients; 6.0% difference, 95% CI 0.6% to 11.8%; p=0.03), but the number of patients who required reintubation after self-extubation was similar (five patients vs three patients; 1.2% difference, 95% CI -5.2% to 2.5%; p=0.47), as were total reintubation rates (13.8%vs 12.5%; 1.3% difference, 95% CI -8.6% to 6.1%; p=0.73). At any instant during the year after enrolment, patients in the intervention group were less likely to die than were patients in the control group (HR 0.68, 95% CI 0.50 to 0.92; p=0.01). For every seven patients treated with the intervention, one life was saved (number needed to treat was 7.4, 95% CI 4.2 to 35.5).

INTERPRETATION

Our results suggest that a wake up and breathe protocol that pairs daily spontaneous awakening trials (ie, interruption of sedatives) with daily spontaneous breathing trials results in better outcomes for mechanically ventilated patients in intensive care than current standard approaches and should become routine practice.

Conventional transbronchial needle aspiration decreases the rate of surgical sampling of intrathoracic lymphadenopathy

BACKGROUND

Previous studies have suggested a decreased need for the surgical biopsy of intrathoracic lymph nodes (LNs) due to improved diagnostic rates utilizing transbronchial needle aspiration (TBNA) with endobronchial ultrasound and endoscopic ultrasound. The goal of this study was to determine whether conventional TBNA using combined cytologic and histologic analysis of tissue specimens impacted the rates of surgical diagnostic biopsies of patients with intrathoracic lymphadenopathy.

METHODS

Retrospective review at a single academic center. All mediastinal and hilar tissue samples submitted for pathologic analysis over an 8.4-year period were analyzed. Patients were categorized into a "before" group and an "after" group based on two different time periods. The before group underwent only cytologic analysis of Wang needle (19-gauge or 21-gauge) aspirates. The after group had cytologic analysis of aspirates as well as histologic analysis of needle "core" (19 gauge) biopsy specimens. The groups were compared for the rate of intrathoracic LNs sampled by surgical means vs TBNA and the number of times that TBNA averted the need for a surgical diagnostic procedure.

RESULTS

The success of TBNA increased significantly in the after group compared to that in the before group. The yield for the successful sampling of mediastinal and hilar LNs increased from 53 to 91% (p < 0.001) in the before group vs the after group. TBNA averted a surgical biopsy in 35% of the before cases compared to 66% of the after cases (p < 0.001).

CONCLUSIONS

Conventional TBNA using large-bore needles with both cytology and surgical pathology evaluation decreases the need for surgical sampling of the mediastinum to diagnose thoracic lymphadenopathy.

Daily sedative interruption in mechanically ventilated patients at risk for coronary artery disease*

OBJECTIVES

To determine the prevalence of myocardial ischemia in mechanically ventilated patients with coronary risk factors and compare periods of sedative interruption vs. sedative infusion.

DESIGN

Prospective, blinded observational study.

SETTING

Medical intensive care unit of tertiary care medical center.

PATIENTS

Intubated, mechanically ventilated patients with established coronary artery disease risk factors.

INTERVENTIONS

Continuous three-lead Holter monitors with ST-segment analysis by a blinded cardiologist were used to detect myocardial ischemia. Ischemia was defined as ST-segment elevation or depression of >0.1 mV from baseline.

MEASUREMENTS AND MAIN RESULTS

Comparisons between periods of awakening from sedation vs. sedative infusion were made. Vital signs, catecholamine levels, and time with ischemia detected by Holter monitor during the two periods were compared. Heart rate, mean arterial pressure, rate-pressure product, respiratory rate, and catecholamine levels were all significantly higher during sedative interruption. Eighteen of 74 patients (24%) demonstrated ischemic changes. Patients with myocardial ischemia had a longer intensive care unit length of stay (17.4+/-17.5 vs. 9.6+/-6.7 days, p=.04). Despite changes in vital signs and catecholamine levels during sedative interruption, fraction of ischemic time did not differ between the time awake vs. time sedated [median [interquartile range] of 0% [0, 0] compared with 0% [0, 0] while they were sedated [p=.17]). The finding of similar fractions of ischemic time between awake and sedated states persisted with analysis of the subgroup of 18 patients with ischemia.

CONCLUSIONS

Myocardial ischemia is common in critically ill mechanically ventilated patients with coronary artery disease risk factors. Daily sedative interruption is not associated with an increased occurrence of myocardial ischemia in these patients.