Farid Sadaka

Red blood cell transfusions and nosocomial infections in critically ill patients.

Objective:A previous retrospective evaluation of Project Impact data demonstrated an association between red blood cell transfusions, nosocomial infections, and poorer outcomes in critically ill patients, independent of survival probability or patient age. The objective of this study was to determine whether transfused patients, independent of survival probability based on Mortality Prediction Model scores, have higher nosocomial infection rates, longer intensive care unit and hospital lengths of stay, and higher mortality rates than nontransfused patients. Design:Prospective, observational, cohort study. Setting:A single-center, mixed medical/surgical, closed intensive care unit. Patients:Adults admitted to St. John’s Mercy Medical Center between August 2001 and June 2003 (n = 2,085) were enrolled using Project Impact software. Both nonoperative and postoperative populations were represented, and transfusion decisions were made independently of patient study inclusion. Patients whose nosocomial infection was diagnosed before transfusion were counted as nontransfused. Interventions:None. Measurements and Main Results:Nosocomial infections, mortality rates, and intensive care unit and hospital length of stay were the main outcome measures. Of the 2,085 patients enrolled, 21.5% received red blood cell transfusions. The posttransfusion nosocomial infection rate was 14.3% in 428 evaluable patients, significantly higher than that observed in nontransfused patients (5.8%; p < .0001, chi-square). In a multivariate analysis controlling for patient age, maximum storage age of red blood cells, and number of red blood cell transfusions, only the number of transfusions was independently associated with nosocomial infection (odds ratio 1.097; 95% confidence interval 1.028–1.171; p = .005). When corrected for survival probability, the risk of nosocomial infection associated with red blood cell transfusions remained statistically significant (p < .0001). Leukoreduction tended to reduce the nosocomial infection rate but not significantly. Mortality and length of stay (intensive care unit and hospital) were significantly higher in transfused patients, even when corrected for illness severity. Conclusions:Red blood cell transfusions should be used sparingly, bearing in mind the potential risks of infection and poor outcomes in critically ill patients. LEARNING OBJECTIVESOn completion of this article, the reader should be able to: Explain the influence of red cell transfusions on nosocomial infection (NI) in critically ill patients. Describe the impact of transfusions on patient outcomes. Use this information in a clinical setting. Dr. Trottier has disclosed that he is an Airway Consultant for Smith’s Medical. Mr. Fu has disclosed that he is an employee of John & Johnson Pharmaceutical. All remaining authors have disclosed that they have no financial relationships with or interests in any commercial companies pertaining to this educational activity. Lippincott CME Institute, Inc., has identified and resolved all faculty conflicts of interest regarding this educational activity. Visit the Critical Care Medicine Web site (www.ccmjournal.org) for information on obtaining continuing medical education credit.

International study on microcirculatory shock occurrence in acutely ill patients

Objectives:Microcirculatory alterations are associated with adverse outcome in subsets of critically ill patients. The prevalence and significance of microcirculatory alterations in the general ICU population are unknown. We studied the prevalence of microcirculatory alterations in a heterogeneous ICU population and its predictive value in an integrative model of macro- and microcirculatory variables. Design:Multicenter observational point prevalence study. Setting:The Microcirculatory Shock Occurrence in Acutely ill Patients study was conducted in 36 ICUs worldwide. Patients:A heterogeneous ICU population consisting of 501 patients. Interventions:None. Measurements and Main Results:Demographic, hemodynamic, and laboratory data were collected in all ICU patients who were 18 years old or older. Sublingual Sidestream Dark Field imaging was performed to determine the prevalence of an abnormal capillary microvascular flow index (< 2.6) and its additional value in predicting hospital mortality. In 501 patients with a median Acute Physiology and Chronic Health Evaluation II score of 15 (10–21), a Sequential Organ Failure Assessment score of 5 (2–8), and a hospital mortality of 28.4%, 17% exhibited an abnormal capillary microvascular flow index. Tachycardia (heart rate > 90 beats/min) (odds ratio, 2.71; 95% CI, 1.67–4.39; p < 0.001), mean arterial pressure (odds ratio, 0.979; 95% CI, 0.963–0.996; p = 0.013), vasopressor use (odds ratio, 1.84; 95% CI, 1.11–3.07; p = 0.019), and lactate level more than 1.5 mEq/L (odds ratio, 2.15; 95% CI, 1.28–3.62; p = 0.004) were independent risk factors for hospital mortality, but not abnormal microvascular flow index. In reference to microvascular flow index, a significant interaction was observed with tachycardia. In patients with tachycardia, the presence of an abnormal microvascular flow index was an independent, additive predictor for in-hospital mortality (odds ratio, 3.24; 95% CI, 1.30–8.06; p = 0.011). This was not true for nontachycardic patients nor for the total group of patients. Conclusions:In a heterogeneous ICU population, an abnormal microvascular flow index was present in 17% of patients. This was not associated with mortality. However, in patients with tachycardia, an abnormal microvascular flow index was independently associated with an increased risk of hospital death.

Fluid resuscitation in septic shock: the effect of increasing fluid balance on mortality.

Purpose: To determine whether progressively increasing fluid balance after initial fluid resuscitation for septic shock is associated with increased mortality. Methods: A retrospective review of the use of intravenous fluids in patients with septic shock in a large university affiliated hospital with 56 medical–surgical intensive care unit beds. We analyzed the data of 350 patients with septic shock who were managed according to the Surviving Sepsis Campaign guidelines. Based on net fluid balance at 24 hours, we examined the results of increase in positive fluid balance on the risk of in-hospital mortality. Patients were divided into 4 groups based on the amount of fluid balance by 24 hours, based on 6-L aliquots. Results: At 24 hours, the average fluid balance was +6.5 L. After correcting for age and sequential organ failure assessment score, a more positive fluid balance at 24 hours significantly increased the risk of in-hospital mortality. Using Cox proportional hazard analysis, excess 12-, 18-, and 24-L positive fluid balance had higher risk of mortality than those patients with a neutral to positive 6-L fluid balance (reference group). Adjusted hazard ratios, 1.519 (95% confidence interval [CI], 1.353-1.685), 1.740 (95% CI, 1.467-2.013), and 1.620 (95% CI, 1.197-2.043), respectively, P < .05. Conclusion: In patients with septic shock resuscitated according to current guidelines, a more positive fluid balance at 24 hours is associated with an increase in the risk of mortality. Optimal survival occurred at neutral fluid balance and up to 6-L positive fluid balance at 24 hours after the development of septic shock.

The effect of red blood cell transfusion on tissue oxygenation and microcirculation in severe septic patients

BackgroundMicrocirculation plays a vital role in the development of multiple organ failure in severe sepsis. The effects of red blood cell (RBC) transfusions on these tissue oxygenation and microcirculation variables in early severe sepsis are not well defined.MethodsThis is a prospective, observational study of patients with severe sepsis requiring RBC transfusions of one to two units of non-leukoreduced RBCs for a hemoglobin < 7.0, or for a hemoglobin between 7.0 and 9.0 with lactic acidosis or central venous oxygen saturation < 70%. This study took place in a 54-bed, medical-surgical intensive care unit of a university-affiliated hospital. Thenar tissue oxygen saturation was measured by using a tissue spectrometer on 21 patients, and a vaso-occlusive test was performed before and 1 hour after transfusion. The sublingual microcirculation was assessed with a Sidestream Dark Field device concomitantly on 11 of them.ResultsRBC transfusion resulted in increase in hemoglobin (7.23 (± 0.87) to 8.75 (± 1.06) g/dl; p < 0.001). RBC transfusion did not globally affect near-infrared spectrometry (NIRS)-derived variables. However, percent change in muscle oxygen consumption was negatively correlated with baseline (r = - 0.679, p = 0.001). There was no statistically significant correlation between percent change in vascular reactivity and baseline (p = 0.275). There was a positive correlation between percent change in oxygen consumption and percent change in vascular reactivity (r = 0.442, p = 0.045). In the 11 patients, RBC transfusion did not globally affect NIRS-derived variables or SDF-derived variables. There was no statistically significant correlation between percent change in small vessel perfusion and baseline perfusion (r = -0.474, p = 0.141), between percent change in small vessel flow and baseline flow (r = -0.418, p = 0.201), or between percent change in small vessel perfusion and percent change in small vessel flow (r = 0.435, p = 0.182).ConclusionsIn a small sample population, muscle tissue oxygen consumption, microvascular reactivity and sublingual microcirculation were globally unaltered by RBC transfusion in severe septic patients. However, muscle oxygen consumption improved in patients with low baseline and deteriorated in patients with preserved baseline. Future research with larger samples is needed to further examine the association between RBC transfusion and outcomes of patients resuscitated early in severe sepsis, with an emphasis on elucidating the potential contribution of microvascular factors.

Red Cell Distribution Width and Outcome in Patients With Septic Shock

Introduction: Red cell distribution width (RDW) is reflective of systemic inflammation. The objective of this study was to investigate the association between RDW (on day 1 of development of septic shock) and mortality. Methods: A total of 279 patients with septic shock were included. We categorized the patients into quintiles based on RDW as follows: <13.5%, 13.5% to 15.5%, 15.6% to 17.5%, 17.5% to 19.4%, and >19.4%. Results: Red cell distribution width was a strong predictor of hospital mortality with a significant risk gradient across RDW quintiles after multivariable adjustment: RDW 13.5% to 15.5% (odds ratio [OR], 4.6; 95% confidence interval [CI], 1.0-23.4; P = .06); RDW 15.6% to 17.5% (OR, 8.0; 95% CI, 1.5-41.6; P = .01); RDW 17.6% to 19.4% (OR, 25.3; 95% CI, 4.3-149.2; P < .001); and RDW >19.4% (OR, 12.3; 95% CI, 2.1-73.3; P = .006), all relative to patients with RDW <13.5%. Similar significant robust associations were present for intensive care unit mortality. Estimating the receiver–operating characteristic area under the curve (AUC) showed that RDW has very good discriminative power for hospital mortality (AUC = 0.74). The AUC was 0.69 for Acute Physiologic and Chronic Health Evaluation II (APACHE II) and 0.69 for sequential organ failure assessment (SOFA). When adding RDW to APACHE II, the AUC increased from 0.69 to 0.77. Conclusions: Red cell distribution width on day 1 of septic shock is a robust predictor of mortality. The RDW is inexpensive and commonly measured. The RDW fared better than either APACHE II or SOFA, and the sum of RDW and APACHE II was a stronger predictor of mortality than either one alone.

Telemedicine Intervention Improves ICU Outcomes

Telemedicine for the intensive care unit (Tele-ICU) was founded as a means of delivering the clinical expertise of intensivists located remotely to hospitals with inadequate access to intensive care specialists. This was a retrospective pre- and postintervention study of adult patients admitted to a community hospital ICU. The patients in the preintervention period (n = 630) and during the Tele-ICU period (n = 2193) were controlled for baseline characteristics, acute physiologic scores (APS), and acute physiologic and health evaluation (APACHE IV) scores. Mean APS scores were 37.1 (SD, 22.8) and 37.7 (SD, 19.4) (P = 0.56), and mean APACHE IV scores were 49.7 (SD, 24.8) and 50.4 (SD, 21.0) (P = 0.53), respectively. ICU mortality was 7.9% during the preintervention period compared with 3.8% during the Tele-ICU period (odds ratio (OR) = 0.46, 95% confidence interval (CI), 0.32–0.66, P < 0.0001). ICU LOS in days was 2.7 (SD, 4.1) compared with 2.2 (SD, 3.4), respectively (hazard ratio (HR) = 1.16, 95% CI, 1.00–1.40, P = 0.01). Implementation of Tele-ICU intervention was associated with reduced ICU mortality and ICU LOS. This suggests that there are benefits of a closed Tele-ICU intervention beyond what is provided by daytime bedside physicians.

Continuous Electroencephalogram in Comatose Postcardiac Arrest Syndrome Patients Treated With Therapeutic Hypothermia Outcome Prediction Study

Purpose: Therapeutic Hypothermia (TH) is the only therapeutic intervention proven to significantly improve survival and neurologic outcome in comatose postcardiac arrest patients and is now considered standard of care. When we discuss prognostication with regard to comatose survivors postcardiac arrest, we should look for tools that are both reliable and accurate and that achieve a false-positive rate (FPR) equal to or very closely approaching zero. Methods: We retrospectively reviewed data that were prospectively collected on all cardiac arrest patients admitted to our ICU. Continuous electroencephalogram (cEEG) monitoring was performed as part of our protocol for therapeutic hypothermia in comatose postcardiac arrest patients. The primary outcome measure was the best score on hospital discharge on the 5-point Glasgow-Pittsburgh cerebral performance category (CPC) scores. Results: A total of 58 patients were included in this study. Twenty five (43%) patients had a good neurologic outcome (CPC score of 1-2). Three (5.2%) patients had nonconvulsive status epilepticus, all of whom had poor outcome (CPC = 5). Seventeen (29%) patients had burst suppression (BS); all had poor outcome. Both nonconvuslsive seizures (NCS) and BS had a specificity of 100% (95% confidence interval [CI], 84%-100%), positive predictive values of 100% (95% CI, 31%-100%), and 100% (95% CI, 77%-100%), respectively. Both NCS and BS had FPRs of zero (95% CI, 0.0-0.69, and 0.0-0.23, respectively). Conclusions: In comatose postcardiac arrest patients treated with hypothermia, EEG during the maintenance and rewarming phase of hypothermia can contribute to prediction of neurologic outcome. Pending large multicenter prospective studies evaluating the role of cEEG in prognostication, our study adds to the existing evidence that cEEG can play a potential role in prediction of outcome in postcardiac arrest patients treated with hypothermia.

Comparison of the Full Outline of UnResponsiveness score and the Glasgow Coma Scale in predicting mortality in critically ill patients

Objective:Impaired consciousness has been incorporated in prediction models that are used in the ICU. The Glasgow Coma Scale has value but is incomplete and cannot be assessed in intubated patients accurately. The Full Outline of UnResponsiveness score may be a better predictor of mortality in critically ill patients. Setting:Thirteen ICUs at five U.S. hospitals. SubjectsOne thousand six hundred ninety-five consecutive unselected ICU admissions during a six-month period in 2012. Design:Glasgow Coma Scale and Full Outline of UnResponsiveness score were recorded within 1 hour of admission. Baseline characteristics and physiologic components of the Acute Physiology and Chronic Health Evaluation system, as well as mortality were linked to Glasgow Coma Scale/Full Outline of UnResponsiveness score information. Interventions:None. Measurements and Results:We recruited 1,695 critically ill patients, of which 1,645 with complete data could be linked to data in the Acute Physiology and Chronic Health Evaluation system. The area under the receiver operating characteristic curve of predicting ICU mortality using the Glasgow Coma Scale was 0.715 (95% CI, 0.663–0.768) and using the Full Outline of UnResponsiveness score was 0.742 (95% CI, 0.694–0.790), statistically different (p = 0.001). A similar but nonsignificant difference was found for predicting hospital mortality (p = 0.078). The respiratory and brainstem reflex components of the Full Outline of UnResponsiveness score showed a much wider range of mortality than the verbal component of Glasgow Coma Scale. In multivariable models, the Full Outline of UnResponsiveness score was more useful than the Glasgow Coma Scale for predicting mortality. Conclusions:The Full Outline of UnResponsiveness score might be a better prognostic tool of ICU mortality than the Glasgow Coma Scale in critically ill patients, most likely a result of incorporating brainstem reflexes and respiration into the Full Outline of UnResponsiveness score.

Placement of intracranial pressure monitors by neurointensivists: Case series and a systematic review

Primary objective: Placement of an intracranial pressure (ICP) monitor to guide the management of patients with severe traumatic brain injury (TBI) has been historically performed by neurosurgeons. It is hypothesized that ICP monitors can be placed by non-surgeon neurointensivists, with placement success and complication rates comparable to neurosurgeons. Research design: Retrospective review and systematic review of the literature. Methods and procedures: This study reviewed the medical records of patients with TBI who required insertion of parenchymal ICP monitors performed by four neurointensivists in a large level I trauma centre. Patient data recorded were age, gender, CT findings, ICP monitor placement, location and length of placement, complications related to the ICP monitor and patient outcomes. Main outcomes and results: Thirty-eight (38) monitors (Camino) were placed. Patients’ average age was 43.0 years (SD = 21.6); 76% were males. The location of monitor was right frontal in 89% and left frontal in 11%. Mean ICP was 24 (SD = 15), duration of ICP monitor was 4.9 days (SD = 3.6). All monitors were placed successfully. There were no major technical complications, no episodes of major catheter-induced intracranial haemorrhage and no infectious complications. These findings were comparable to published outcomes from neurosurgeon placements. Conclusions: It is believed that insertion of ICP monitors by neurointensivists is safe and may aid in providing prompt monitoring of patients with severe TBI.

Therapeutic hypothermia for a comatose survivor of near-hanging.

Therapeutic hypothermia is recommended for comatose survivors of cardiac arrest. Therapeutic hypothermia ameliorates multiple pathophysiologic mechanisms involved in ischemia-reperfusion injury, which may occur after cardiac arrest and near-hanging. Therapeutic hypothermia has not been prospectively studied in near-hanging. Victims of near-hanging suffer from strangulation with cerebral ischemia and resultant reperfusion injury rather than a fatal cervical spine injury. We report a case where therapeutic hypothermia was applied to a comatose survivor of near-hanging. A 41-year-old man presented with coma following attempted suicide by hanging. The patient underwent 24 hours of mild therapeutic hypothermia. The patient was discharged without neurologic sequelae and a Modified Rankin Scale of 0 (back to his baseline status). We present a case where therapeutic hypothermia was used safely and successfully in a patient without cardiac arrest but still in coma after attempted suicide by hanging. No randomized controlled trials on therapeutic hypothermia for comatose survivors of near-hanging victims have been published. However, in the absence of better evidence, it seems reasonable to consider hypothermia treatment in comatose near-hanging victims until more evidence can be obtained.