Ognjen Gajic

Transfusion related acute lung injury: incidence and risk factors

Transfusion-related acute lung injury (TRALI) is the leading cause of transfusion-related mortality. To determine TRALI incidence by prospective, active surveillance and to identify risk factors by a case-control study, 2 academic medical centers enrolled 89 cases and 164 transfused controls. Recipient risk factors identified by multivariate analysis were higher IL-8 levels, liver surgery, chronic alcohol abuse, shock, higher peak airway pressure while being mechanically ventilated, current smoking, and positive fluid balance. Transfusion risk factors were receipt of plasma or whole blood from female donors (odds ratio = 4.5, 95% confidence interval [CI], 1.85-11.2, P = .001), volume of HLA class II antibody with normalized background ratio more than 27.5 (OR = 1.92/100 mL, 95% CI, 1.08-3.4, P = .03), and volume of anti-human neutrophil antigen positive by granulocyte immunofluoresence test (OR = 1.71/100 mL, 95% CI, 1.18-2.5, P = .004). Little or no risk was associated with older red blood cell units, noncognate or weak cognate class II antibody, or class I antibody. Reduced transfusion of plasma from female donors was concurrent with reduced TRALI incidence: 2.57 (95% CI, 1.72-3.86) in 2006 versus 0.81 (95% CI, 0.44-1.49) in 2009 per 10 000 transfused units (P = .002). The identified risk factors provide potential targets for reducing residual TRALI.

Early Identification of Patients at Risk of Acute Lung Injury: Evaluation of Lung Injury Prediction Score in a Multicenter Cohort Study

RATIONALE Accurate, early identification of patients at risk for developing acute lung injury (ALI) provides the opportunity to test and implement secondary prevention strategies. OBJECTIVES To determine the frequency and outcome of ALI development in patients at risk and validate a lung injury prediction score (LIPS). METHODS In this prospective multicenter observational cohort study, predisposing conditions and risk modifiers predictive of ALI development were identified from routine clinical data available during initial evaluation. The discrimination of the model was assessed with area under receiver operating curve (AUC). The risk of death from ALI was determined after adjustment for severity of illness and predisposing conditions. MEASUREMENTS AND MAIN RESULTS Twenty-two hospitals enrolled 5,584 patients at risk. ALI developed a median of 2 (interquartile range 1-4) days after initial evaluation in 377 (6.8%; 148 ALI-only, 229 adult respiratory distress syndrome) patients. The frequency of ALI varied according to predisposing conditions (from 3% in pancreatitis to 26% after smoke inhalation). LIPS discriminated patients who developed ALI from those who did not with an AUC of 0.80 (95% confidence interval, 0.78-0.82). When adjusted for severity of illness and predisposing conditions, development of ALI increased the risk of in-hospital death (odds ratio, 4.1; 95% confidence interval, 2.9-5.7). CONCLUSIONS ALI occurrence varies according to predisposing conditions and carries an independently poor prognosis. Using routinely available clinical data, LIPS identifies patients at high risk for ALI early in the course of their illness. This model will alert clinicians about the risk of ALI and facilitate testing and implementation of ALI prevention strategies. Clinical trial registered with www.clinicaltrials.gov (NCT00889772).

The Importance of Fluid Management in Acute Lung Injury Secondary to Septic Shock

BACKGROUND Recent studies have suggested that early goal-directed resuscitation of patients with septic shock and conservative fluid management of patients with acute lung injury (ALI) can improve outcomes. Because these may be seen as potentially conflicting practices, we set out to determine the influence of fluid management on the outcomes of patients with septic shock complicated by ALI. METHODS A retrospective analysis was performed at Barnes-Jewish Hospital (St. Louis, MO) and in the medical ICU of Mayo Medical Center (Rochester, MN). Patients hospitalized with septic shock were enrolled into the study if they met the American-European Consensus definition of ALI within 72 h of septic shock onset. Adequate initial fluid resuscitation (AIFR) was defined as the administration of an initial fluid bolus of >or= 20 mL/kg prior to and achievement of a central venous pressure of >or= 8 mm Hg within 6 h after the onset of therapy with vasopressors. Conservative late fluid management (CLFM) was defined as even-to-negative fluid balance measured on at least 2 consecutive days during the first 7 days after septic shock onset. RESULTS The study cohort was made up of 212 patients with ALI complicating septic shock. Hospital mortality was statistically lowest for those achieving both AIFR and CLFM and higher for those achieving only CLFM, those achieving only AIFR, and those achieving neither (17 of 93 patients [18.3%] vs 13 of 31 patients [41.9%] vs 30 of 53 patients [56.6%] vs 27 of 35 [77.1%], respectively; p < 0.001). CONCLUSIONS Both early and late fluid management of septic shock complicated by ALI can influence patient outcomes.

Intraoperative Tidal Volume as a Risk Factor for Respiratory Failure after Pneumonectomy

Background:Respiratory failure is a leading cause of postoperative morbidity and mortality in patients undergoing pneumonectomy. The authors hypothesized that intraoperative mechanical ventilation with large tidal volumes (VTs) would be associated with increased risk of postpneumonectomy respiratory failure. Methods:Patients undergoing elective pneumonectomy at the authors’ institution from January 1999 to January 2003 were studied. The authors collected data on demographics, relevant comorbidities, neoadjuvant therapy, pulmonary function tests, site and type of operation, duration of surgery, intraoperative ventilator settings, and intraoperative fluid administration. The primary outcome measure was postoperative respiratory failure, defined as the need for continuation of mechanical ventilation for greater than 48 h postoperatively or the need for reinstitution of mechanical ventilation after extubation. Results:Of 170 pneumonectomy patients who met inclusion criteria, 30 (18%) developed postoperative respiratory failure. Causes of postoperative respiratory failure were acute lung injury in 50% (n = 15), cardiogenic pulmonary edema in 17% (n = 5), pneumonia in 23% (n = 7), bronchopleural fistula in 7% (n = 2), and pulmonary thromboembolism in 3% (n = 1). Patients who developed respiratory failure were ventilated with larger intraoperative VT than those who did not (median, 8.3 vs. 6.7 ml/kg predicted body weight; P < 0.001). In a multivariate regression analysis, larger intraoperative VT (odds ratio, 1.56 for each ml/kg increase; 95% confidence interval, 1.12–2.23) was associated with development of postoperative respiratory failure. The interaction between larger VT and fluid administration was also statistically significant (odds ratio, 1.36; 95% confidence interval, 1.05–1.97). Conclusion:Mechanical ventilation with large intraoperative VT is associated with increased risk of postpneumonectomy respiratory failure.

Transfusion‐related acute lung injury and pulmonary edema in critically ill patients: a retrospective study

BACKGROUND: Using the recent Consensus Panel recommendations, we sought to describe the incidence of transfusion‐related acute lung injury (TRALI) and transfusion‐associated circulatory overload (TACO) in critically ill patients.

What Tidal Volumes Should Be Used in Patients without Acute Lung Injury

Mechanical ventilation practice has changed over the past few decades, with tidal volumes (VT) decreasing significantly, especially in patients with acute lung injury (ALI). Patients without acute lung injury are still ventilated with large—and perhaps too large—VT. Studies of ventilator-associated lung injury in subjects without ALI demonstrate inconsistent results. Retrospective clinical studies, however, suggest that the use of large VT favors the development of lung injury in these patients. Side effects associated with the use of lower VT in patients with ALI seem to be minimal. Assuming that this will be the case in patients without ALI/acute respiratory distress syndrome too, the authors suggest that the use of lower VT should be considered in all mechanically ventilated patients whether they have ALI or not. Prospective studies should be performed to evaluate optimal ventilator management strategies for patients without ALI.

Beyond mortality: Future clinical research in acute lung injury

Mortality in National Heart, Lung and Blood Institute-sponsored clinical trials of treatments for acute lung injury (ALI) has decreased dramatically during the past two decades. As a consequence, design of such trials based on a mortality outcome requires ever-increasing numbers of patients. Recognizing that advances in clinical trial design might be applicable to these trials and might allow trials with fewer patients, the National Heart, Lung and Blood Institute convened a workshop of extramural experts from several disciplines. The workshop assessed the current state of clinical research addressing ALI, identified research needs, and recommended: (1) continued performance of trials evaluating treatments of patients with ALI; (2) development of strategies to perform ALI prevention trials; (3) observational studies of patients without ALI undergoing prolonged mechanical ventilation; and (4) development of a standardized format for reporting methods, endpoints, and results of ALI trials.

Effect of 24-hour mandatory versus on-demand critical care specialist presence on quality of care and family and provider satisfaction in the intensive care unit of a teaching hospital*

Objective:The benefit of continuous on-site presence by a staff academic critical care specialist in the intensive care unit of a teaching hospital is not known. We compared the quality of care and patient/family and provider satisfaction before and after changing the staffing model from on-demand to continuous 24-hr critical care specialist presence in the intensive care unit. Design:Two-year prospective cohort study of patient outcomes, processes of care, and family and provider survey of satisfaction, organization, and culture in the intensive care unit. Setting:Intensive care unit of a teaching hospital. Patients:Consecutive critically ill patients, their families, and their caregivers. Interventions:Introduction of night-shift coverage to provide continuous 24-hr on-site, as opposed to on-demand, critical care specialist presence. Measurements and Main Results:Of 2,622 patients included in the study, 1,301 were admitted before and 1,321 after the staffing model change. Baseline characteristics and adjusted intensive care unit and hospital mortality were similar between the two groups. The nonadherence to evidence-based care processes improved from 24% to 16% per patient-day after the staffing change (p = .002). The rate of intensive care unit complications decreased from 11% to 7% per patient-day (p = .023). When adjusted for predicted hospital length of stay, admission source, and do-not-resuscitate status, hospital length of stay significantly decreased during the second period (adjusted mean difference −1.4, 95% confidence interval −0.3 to −2.5 days, p = .017). The new model was considered optimal for patient care by the majority of the providers (78% vs. 38% before the intervention, p < .001). Family satisfaction was excellent during both study periods (mean score 5.87 ± 1.7 vs. 5.95 ± 2.0, p = .777). Conclusions:The introduction of continuous (24-hr) on-site presence by a staff academic critical care specialist was associated with improved processes of care and staff satisfaction and decreased intensive care unit complication rate and hospital length of stay.

Pulmonary edema after transfusion: How to differentiate transfusion-associated circulatory overload from transfusion-related acute lung injury

Objective:Pulmonary edema is an underrecognized and potentially serious complication of blood transfusion. Distinct mechanisms include adverse immune reactions and circulatory overload. The former is associated with increased pulmonary vascular permeability and is commonly referred to as transfusion-related acute lung injury (TRALI). The latter causes hydrostatic pulmonary edema and is commonly referred to as transfusion-associated circulatory overload (TACO). In this review article we searched the National Library of Medicine PubMed database as well as references of retrieved articles and summarized the methods for differentiating between hydrostatic and permeability pulmonary edema. Results:The clinical and radiologic manifestations of TACO and TRALI are similar. Although echocardiography and B-type natriuretic peptide measurements may aid in the differential diagnosis between hydrostatic and permeability pulmonary edema, invasive techniques such as right heart catheterization and the sampling of alveolar fluid protein are sometimes necessary. The diagnostic differentiation is especially difficult in critically ill patients will multiple comorbidities so that the cause of edema may only be determined post hoc based on the clinical course and response to therapy. Guided by available evidence, we present an algorithm for establishing the pretest probability of TRALI as opposed to TACO. The decision to test donor and recipient blood for immunocompatibility may be made on this basis. Conclusions:The distinction between hydrostatic (TACO) and permeability (TRALI) pulmonary edema after transfusion is difficult, in part because the two conditions may coexist. Knowledge of strengths and limitations of different diagnostic techniques is necessary before initiation of complex TRALI workup.

Fresh frozen plasma transfusion in critically ill medical patients with coagulopathy

Objective:Although restrictive red cell transfusion practice has become a standard of care in the critically ill, data on the use of fresh frozen plasma (FFP) are limited. We hypothesized that the practice of FFP transfusion in the medical intensive care unit is variable and that liberal use may not be associated with improved outcome. Design:Retrospective cohort study. Setting:A 24-bed medical intensive care unit in a tertiary referral center. Patients:All patients admitted to a medical intensive care unit during a 5-month period who had abnormal coagulation defined as international normalized ratio (INR) of ≥1.5-times normal. Interventions:None. Measurements and Main Results:We collected data on demographics, severity of illness as measured by Acute Physiology and Chronic Health Evaluation (APACHE) III scores, INR, bleeding episodes, and transfusion complications. We identified 115 patients with coagulopathy (INR of ≥1.5) but without active bleeding. A total of 44 patients (38.3%) received FFP transfusion. INR was corrected in 16 of 44 patients (36%) who received transfusion. Median dose of FFP was 17 mL/kg in patients who had INR corrected vs. 10 mL/kg in those who did not (p = .018). There was no difference in age, sex, APACHE III scores, liver disease, Coumadin treatment, or INR level between those who did and did not receive FFP. Invasive procedures (68.2% vs. 40.8%, p = .004) and history of recent gastrointestinal bleeding (41% vs. 7%, p < .001) were more frequent in the group with transfusion. Although there was no difference in new bleeding episodes (6.8% in transfused vs. 2.8% in nontransfused group, p = .369), new onset acute lung injury was more frequent in the transfused group (18% vs. 4%, p = .021). Adjusted for severity of illness, hospital mortality and intensive care unit length of stay among survivors were not different between the two groups. Conclusion:The risk–benefit ratio of FFP transfusion in critically ill medical patients with coagulopathy may not be favorable. Randomized controlled trials evaluating restrictive vs. liberal FFP transfusion strategies are warranted.