Thrombocytopenia and prognosis in intensive care

Bacillus anthracis peptidoglycan activates human platelets through FcγRII and complement

Platelet activation frequently accompanies sepsis and contributes to the sepsis-associated vascular leakage and coagulation dysfunction. Our previous work has implicated peptidoglycan (PGN) as an agent causing systemic inflammation in gram-positive sepsis. We used flow cytometry and fluorescent microscopy to define the effects of PGN on the activation of human platelets. PGN induced platelet aggregation, expression of the activated form of integrin αIIbβ3, and exposure of phosphatidylserine (PS). These changes were dependent on immunoglobulin G and were attenuated by the Fcγ receptor IIa-blocking antibody IV.3, suggesting they are mediated by PGN-anti-PGN immune complexes signaling through Fcγ receptor IIa. PS exposure was not blocked by IV.3 but was sensitive to inhibitors of complement activation. PGN was a potent activator of the complement cascade in human plasma and caused deposition of C5b-9 on the platelet surface. Platelets with exposed PS had greatly accelerated prothrombinase activity. We conclude that PGN derived from gram-positive bacteria is a potent platelet agonist when complexed with anti-PGN antibody and could contribute to the coagulation dysfunction accompanying gram-positive infections.

The evaluation of sequential platelet counts has prognostic value for acute kidney injury patients requiring dialysis in the intensive care setting

OBJECTIVE

To evaluate the prognostic value of platelet counts in acute kidney injury patients requiring renal replacement therapy.

METHODS

This prospective cohort study was performed in three tertiary-care hospitals. Platelet counts were obtained upon admission to the intensive care unit and during the first week of renal replacement therapy on days 1, 3, 5 and 7. The outcome of interest was the hospital mortality rate. With the aim of minimizing individual variation, we analyzed the relative platelet counts on days 3, 5, 7 and at the point of the largest variation during the first week of renal replacement therapy. Logistic regression analysis was used to test the prognostic value of the platelet counts.

RESULTS

The study included 274 patients. The hospital mortality rate was 62%. The survivors had significantly higher platelet counts upon admission to the intensive care unit compared to the non-survivors [175.5×10(3)/mm(3) (108.5-259×10(3)/mm(3)) vs. 148×10(3)/mm(3) (80-141×10(3)/mm(3))] and during the first week of renal replacement therapy. The relative platelet count reductions were significantly associated with a higher hospital mortality rate compared with the platelet count increases (70% vs. 44% at the nadir, respectively). A relative platelet count reduction >60% was significantly associated with a worse outcome (mortality rate=82.6%). Relative platelet count variations and the percentage of reduction were independent risk factors of hospital mortality during the first week of renal replacement therapy.

CONCLUSION

Platelet counts upon admission to the intensive care unit and at the beginning of renal replacement therapy as well as sequential platelet count evaluation have prognostic value in acute kidney injury patients requiring renal replacement therapy.

In-line filtration minimizes organ dysfunction: new aspects from a prospective, randomized, controlled trial

BACKGROUND

Infused particles induce thrombogenesis, impair microcirculation and modulate immune response. We have previously shown in critically ill children, that particle-retentive in-line filtration reduced the overall complication rate of severe events, length of stay and duration of mechanical ventilation. We now evaluated the influence of in-line filtration on different organ function and thereby elucidated the potential underlying pathophysiological effects of particle infusion.

METHODS

In this single-centre, prospective, randomized controlled trial 807 critically ill children were assigned to either control (n = 406) or filter group (n = 401), the latter receiving in-line filtration for complete infusion therapy. Both groups were compared regarding the differences of incidence rates and its 95% confidence interval (CI) of different organ dysfunction as defined by the International Pediatric Sepsis Consensus Conference 2005.

RESULTS

The incidence rates of respiratory (-5.06%; 95% CI, -9.52 to -0.59%), renal (-3.87%; 95% CI, -7.58 to -0.15%) and hematologic (-3.89%; 95% CI, -7.26 to -0.51%) dysfunction were decreased in the filter group. No difference was demonstrated for the occurrence rates of cardiovascular, hepatic, or neurologic dysfunction between both groups.

CONCLUSIONS

In-line filtration has beneficial effects on the preservation of hematologic, renal and respiratory function in critically ill patients. The presented clinical data further support our hypothesis regarding potential harmful effects of particles. In critically ill patients infused particles may lead to further deterioration of the microcirculation, induce a systemic hypercoagulability and inflammation with consecutive negative effects on organ function.

TRIAL REGISTRATION

ClinicalTrials.gov number; NCT00209768.

The prevalence and outcomes of thrombocytopenia in a neonatal intensive care unit: a three-year report

Neonatal thrombocytopenia is one of the most common hematologic disorders in neonatal intensive care units (NICUs). The purpose of this study was to determine the prevalence of thrombocytopenia and whether thrombocytopenia has an effect on the occurrence of intraventricular hemorrhage (IVH) ≥ grade 2 and on mortality rate. This study was carried out retrospectively in neonates admitted to NICU of Cumhuriyet University in Sivas, Turkey, between 2009 and 2012. Among 2218 neonates evaluated, 208 (9.4%) developed thrombocytopenia. The prevalence of IVH ≥ grade 2 was more in infants with thrombocytopenia (7.2%) than in those without thrombocytopenia (4.4%), although this was not statistically significant (P = .08). In univariate analysis, IVH ≥ grade 2 was higher in cases with very severe thrombocytopenia (35.7%, n = 5) than in those with mild (2.1%, n = 2), moderate (4.7%, n = 3), and severe thrombocytopenia (15.2%, n = 5) (P = .04). Multivariate logistic regression analysis showed that birth weight <1500 g (OR 6.2, 95% CI 3.4-9.8; P = .0001), gram-negative sepsis (OR 2.5, 95% CI 1.8-4.2; P = .01), very severe thrombocytopenia (OR 1.3, 95% CI 1.1-2.1; P = .03), and platelet transfusion ≥2 (OR 7.3, 95% CI 4.1-12.1; P = .001) were significant risk factors for mortality. The results of our study suggest that outcomes of neonates with thrombocytopenia depend not only on platelet count but also on decreased gestational age or birth weight, prenatal factors, and sepsis.

Sequential organ failure assessment (SOFA) scores differ between genders in a sepsis cohort: cause or effect?

BACKGROUND

Controversy exists regarding the influence of gender on sepsis events and outcome. Epidemiological data from other countries may not always apply to local circumstances. The aim of this study was to identify gender differences in patient characteristics, treatment, and outcome related to the occurrence of sepsis at admission to the ICU.

METHODS

A prospective observational cohort study on patients admitted to the ICU over a 3-year period fulfilling sepsis criteria during the first 24 hours. Demographic data, APACHE II score, SOFA score, TISS 76, aetiology, length of stay (LOS), mortality rate, and aspects of treatment were collected and then analysed with respect to gender differences.

RESULTS

There were no gender-related differences in mortality or length of stay. Early organ dysfunction assessed as SOFA score at admission was a stronger risk factor for hospital mortality for women than for men. This discrepancy was mainly associated with the coagulation sub-score. CRP levels differed between genders in relation to hospital mortality. Infection from the abdominopelvic region was more common among women, whereas infection from skin or skin structures were more common in men.

CONCLUSION

In this cohort, gender was not associated with increased mortality during a 2-year follow-up period. SOFA score at ICU admission was a stronger risk factor for hospital mortality for women than for men. The discrepancy was mainly related to the coagulation SOFA sub-score. Together with differences in CRP levels this may suggest differences in inflammatory response patterns between genders.

The incidence, causes, and prognostic significance of new-onset thrombocytopenia in intensive care units: a prospective cohort study in a Korean hospital

This study was designed to investigate the incidence, causes, and outcomes of new-onset thrombocytopenia (NOT) in Korean intensive care units (ICUs). A prospective cohort study was conducted in medical ICUs of Samsung Medical Center between August 2010 and February 2011. All newly admitted patients were included if they stayed in the ICU for more than 48 hr and did not have thrombocytopenia upon admission. A total of 186 patients were included. NOT developed in 37.1%. Most common cause of NOT was sepsis with disseminated intravascular coagulation (66.7%), followed by drug-induced thrombocytopenia (18.8%), and heparin-induced thrombocytopenia (2.9%). IgG-specific antibody to platelet factor 4/heparin was positive in 2.4% among patients treated with heparin, and thrombosis occurred in two patients. Twenty eight-day mortality was higher in patients that developed NOT compared to those that did not develop NOT (39.1% vs 12%, P < 0.001). NOT increased the odds ratio of 28-day mortality and was an independent risk factor for mortality (OR 3.52; 95% CI 1.32-9.38; P = 0.012). In conclusion, NOT is common and is an independent risk factor for mortality in Korean ICU patients. Therefore, clinicians should make every effort to correct the causes of NOT.

Etiology and significance of thrombocytopenia in critically ill patients

Thrombocytopenia is common in critically ill patients and increases morbidity and mortality. A diagnosis of heparin-induced thrombocytopenia (HIT) is frequently considered in any ICU patient who develops thrombocytopenia in the context of ongoing heparin exposure. As the usual tests to diagnose HIT are often neither specific nor sensitive enough to be confirmatory, the intensivist must largely rely on clinical judgment in treatment decisions. Patients in the ICU may also develop thrombocytopenia resulting from non-HIT immune mechanisms, nonimmune platelet consumption, and from decreased platelet production due to preexisting disorders or as a result of their critical illness and/or drug therapy.

Safety and diagnostic yield of renal biopsy in the intensive care unit

PURPOSE

Renal biopsy (RB) is occasionally performed in critically ill patients. The safety and impact of RB in this setting have not been reported.

METHODS

A 10-year (2000-2009) retrospective multicentre study was conducted in ten French intensive care units (ICU) on patients who underwent RB during their management. Medical files were retrieved for data analysis.

RESULTS

Seventy-seven patients underwent an RB of which 68 (88 %) were on a native kidney and 9 (12 %) on a transplanted kidney. Percutaneous ultrasound-guided RB was used in most cases (87 %). Fifty-seven per cent of the patients were on mechanical ventilation at the time of RB. RB-related complications occurred in 17 (22 %) patients, two were graded as severe (requirement for kidney embolization, eventually successful). In 35 (51 %) non-transplanted patients, RB established a specific diagnosis other than acute tubular necrosis (ATN), which was diagnosed in only 18 % of patients. In the remaining patients, only non-specific lesions were observed. Therapeutic modifications followed RB in 14 (21 %) non-transplanted patients. Presence of signs of systemic disease involving the renal tract, occurrence of renal failure before hospital admission, and absence of any factor usually associated with ATN significantly predicted the presence of a specific diagnosis at RB other than ATN.

CONCLUSIONS

In this cohort, the contribution of RB to diagnosis and treatment was undeniable, but at the expense of frequent adverse events although most of them were not considered severe.

Design, conduct, and analysis of a multicenter, pharmacogenomic, biomarker study in matched patients with severe sepsis treated with or without drotrecogin Alfa (activated)

BACKGROUND

A genomic biomarker identifying patients likely to benefit from drotrecogin alfa (activated) (DAA) may be clinically useful as a companion diagnostic. This trial was designed to validate biomarkers (improved response polymorphisms (IRPs)). Each IRP (A and B) contains two single nucleotide polymorphisms that were associated with a differential DAA treatment effect.

METHODS

DAA is typically given to younger patients with greater disease severity; therefore, a well-matched control group is critical to this multicenter, retrospective, controlled, outcome-blinded, genotype-blinded trial. Within each center, DAA-treated patients will be matched to controls treated within 24 months of each other taking into account age, APACHE II, cardiovascular, respiratory, renal, and hematologic dysfunction, mechanical ventilation status, medical/surgical status, and infection site. A propensity score will estimate the probability that a patient would have received DAA given their baseline characteristics. Two-phase data transfer will ensure unbiased selection of matched controls. The first transfer will be for eligibility and matching data and the second transfer for outcomes and genotypic data. The primary analysis will compare the effect of DAA in IRP + and IRP - groups on in-hospital mortality through day 28.

DISCUSSION

A design-based approach matching DAA-free to DAA-treated patients in a multicenter study of patients who have severe sepsis and high risk of death will directly compare control to DAA-treated groups for mortality by genotype. Results, which should be available in 2012, may help to identify the group of patients who would benefit from DAA and may provide a model for future investigation of sepsis therapies.

Serum Antibodies to the Heparin/Platelet Factor 4 Complex Are an Independent Predictor of Thrombotic Complications Following Pediatric Fontan Surgery

Antibodies to the heparin/platelet factor 4 complex (heparin/PF4) are linked to the pathogenesis of heparin-induced thrombocytopenia (HIT) and to the thrombotic complications. We investigated thrombotic events during early follow-up in a pediatric cardiac surgical population to ascertain whether there is a relation between heparin/PF4 antibody concentration and post-surgical thrombotic complications. One hundred and five consecutive pediatric patients treated by Fontan surgery were studied. The presence of serum heparin/PF4 immunoglobulins IgG, IgA, and IgM (collectively termed HIT antibodies) were measured in preoperative and postoperative blood samples by enzyme-linked immunosorbent assay. On day six after Fontan surgery, HIT-related thromboses was identified in total of 11 patients (10.5%). HIT antibodies were detected in 34 of 105 patients (32.4%). The post-surgical nadir platelet count was significantly lower in patients who developed antibodies ( p < 0.001). We found the odds ratio (OR) for this composite endpoint was 4.06 ( p < 0.001). Seropositive status for heparin/PF4 antibodies was an independent predictor of thrombotic events (OR 2.28; p < 0.001). Quintile analysis revealed that the median nadir platelet value was significantly lower in patients with higher HIT antibody titers. Patients in the highest quintile of HIT antibody titer all experienced thrombotic events, while only two thrombotic events occurred in patients in the lowest quintile ( p < 0.001). Heparin-induced thrombocytopenia is a rare occurrence in pediatric cardiac surgical patients. Patients who develop antibodies to the heparin/PF4 complex have a significantly higher rate of postoperative thrombotic events than patients who lack these antibodies. Within the seropositive group, the risk of developing thrombosis increased with the plasma antibody concentration.

Postoperative failure of platelet recovery is an independent risk factor for poor survival in patients with oral and oropharyngeal cancer

OBJECTIVE

The aim of this study was to evaluate the postoperative platelet count changes in patients with oral and oropharyngeal squamous cell carcinoma undergoing preoperative chemoradiotherapy in order to test the hypothesis that the failure of platelets to recover to normal range within 7 days after surgery represents a significant risk factor for poor survival.

MATERIALS AND METHODS

A cohort of 102 patients with primary locally advanced oral and oropharyngeal squamous cell carcinoma undergoing neoadjuvant chemoradiotherapy and surgery was retrospectively analyzed. For each patient, platelet counts were evaluated prior to neoadjuvant treatment, prior to surgery and throughout postoperative days 1 to 7. The Kaplan-Meier method and Cox regression models were used to assess the impact of platelet count changes on survival.

RESULTS

Overall survival rate at 5 years was 28% for patients whose platelets did not recover by day 7, with 52% for patients whose platelets remained within a normal level or recovered to this by day 7 (p = 0.005). In multivariate analysis, failure of platelet recovery by day 7 was independently associated with shorter overall survival (p = 0.03).

CONCLUSIONS

We demonstrated that the failure of platelets to recover to normal range by the seventh postoperative day is an independent adverse prognostic factor in patients with oral and oropharyngeal cancer undergoing neoadjuvant treatment and surgery.

CLINICAL RELEVANCE

Our results indicate that physicians should pay closer attention to monitoring the postoperative platelet count course, as it may predict the clinical outcome of patients with oral and oropharyngeal cancer.

Correction of subclinical coagulation disorders before percutaneous dilatational tracheotomy

BACKGROUND

There is evidence that percutaneous dilatational tracheotomy (PDT) can be safely performed in patients with severe coagulation disorders if these are carefully corrected immediately before the procedure. However, it is currently unclear whether PDT can be performed safely in patients in an Intensive Care Unit (ICU) with uncorrected mild coagulation disorders.

MATERIALS AND METHODS

In a randomised controlled trial we determined the effect of correction of mild coagulation disorders on bleeding during and after PDT. ICU patients planned for bedside PDT with: (i) a prothrombin time (PT) between 14.7-20.0 seconds, (ii) a platelet count between 40-100×10(9)/L and/or (iii) active treatment with acetylsalicylic acid were randomised to receive infusion with fresh-frozen plasma (FFP) and/or platelets ("correction") versus no transfusion ("no correction") before PDT.

RESULTS

We randomised 35 patients to the "correction" group and 37 patients to the "no correction" group. In patients who received FFP, the decrease in PT was marginal (mean decrease 0.40±0.56 seconds); the median increase in platelet counts after transfusion of platelets was 35 [11-47]x10(9)/L. The median blood loss was 3 [IQR: 1-6] grams in the "correction" group and 3 [IQR: 2-6] grams in the "no correction" group (P=0.96).

DISCUSSION

Bleeding during and after bedside PDT in ICU patients with mild coagulation disorders is rare in our setting. Correction of subclinical coagulation disorders by transfusion of FFP and/or platelets does not affect bleeding.

Thrombocytopenia in the Intensive Care Unit

Thrombocytopenia is a common laboratory finding in critically ill patients admitted to the intensive care unit. Potential etiologies of thrombocytopenia are myriad, ranging from acute disease processes and concomitant conditions to exposures and drugs. The mechanism of decreased platelet counts can also be varied: laboratory measurement may be spurious, platelet production may be decreased, or platelet destruction or sequestration may be increased. In addition to evaluation for the cause of thrombocytopenia, the clinician must also guard against spontaneous bleeding due to thrombocytopenia, prophylax against bleeding resulting from an invasive procedure performed in the setting of thrombocytopenia, and treat active bleeding related to thrombocytopenia.

Thrombocyte and Erythrocyte Indices in Sepsis and Disseminated Intravascular Coagulation

Sepsis is the inflammatory response against infection. The existence of DIC during sepsis indicates a poor prognosis and coagulation abnormalities and thrombocytopenia may exist. The aim of this study was to investigate platelet and erythrocyte indices in sepsis patients with DIC and without DIC. In both groups coagulation tests, platelet count and indices, erythrocyte count and indices were retrospectively analysed. In the sepsis plus DIC patients the prothrombin time and D-dimer values were found significantly higher and fibrinogen, platelet and plateletcrit were found significantly lower than in the sepsis without DIC group. The analysis of mean platelet volume, platelet distribution width, erythrocyte count and indices revealed no significant differences between the two groups. These results showed us that the depression of bone marrow in septic patients with DIC and without DIC did not differ. The activation of the coagulation system might probably be the cause of thrombocyte depletion in DIC.

Clinical characteristics and risk factors for mortality in patients with bacteremia caused by Pseudomonas aeruginosa

OBJECTIVE

The mortality rates for bacteremia due to Pseudomonas aeruginosa remain high. In our hospital, we performed retrospective analyses to determine risk factors for mortality among patients with bacteremia caused by P. aeruginosa.

MATERIALS AND METHODS

This retrospective cohort study was conducted among adult patients with bacteremia due to P. aeruginosa at Jikei University Hospital. We analyzed factors, such as age, gender, underlying disease, initial antimicrobial treatment, and primary site of infection to determine which of these were predictive of mortality in patients with P. aeruginosa bacteremia.

RESULTS

One hundred and thirty-four patients with P. aeruginosa bacteremia were identified between April 2003 and March 2010. The 30-day mortality rate among all patients with P. aeruginosa bacteremia was 20.9%. The most common underlying disease was leukemia (20.9%), and the most common primary site of infection was the urinary tract (24.6%). Seventy-one patients (65.7%) were treated with an appropriate initial antimicrobial regimen for P. aeruginosa bacteremia. However, these patients had similar 30-day mortality to that observed in patients not administered appropriate antibiotics. This study revealed that risk factors for the 30-day mortality were thrombocytopenia and polymicrobial P. aeruginosa bacteremia (p<0.01).

CONCLUSION

Thrombocytopenia and polymicrobial bacteremia were associated with a greater incidence of 30-day mortality among patients with P. aeruginosa bacteremia. On the other hand, age, underlying disease, and inappropriate initial empirical antimicrobial treatment did not affect mortality.

A Case of Thrombocytopenia due to Odontogenic Infection

Thrombocytopenia in surgical patients is a potentially serious condition,faced by surgeons. A close relationship between sepsis and thrombocytopenia has been suggested. Thrombocytopenia has even been suggested to be indicative of an acute infection. Platelet count in a septicemic patient may also serve as a prognostic tool. There are many reports of thrombocy-topenia due to septicemia in the literature but the occurrence of thrombocytopenia in maxillofacial infections is rare. Thrombocytopenia in a patient with odontogenic infection presents unique diagnostic and management challenges. A case report of an adult male patient with odontogenic infection, who developed life-threatening thrombocytopenia, is presented.

Analysis of significant decrease in platelet count and thrombocytopenia, graded according to NCI-CTC, as prognostic risk markers for mortality and morbidity

BACKGROUND

In adult intensive care unit, both thrombocytopenia (TP) and ≥30% decrease in platelet count are associated with increased mortality, morbidity, and length of stay (LOS). The above mentioned observations have not been well reported in pediatric population. National Cancer Institute (NCI) common terminology criteria (CTC) is mainly used to report the adverse effects of cancer therapy, but not for grading TP.

METHOD

Retrospective review of medical records was done for 204 patients. TP was graded according to the NCI-CTC. Each grade of TP and significant decrease (≥30%) in platelet count were studied for their association with LOS, mortality, and morbidity such as hospital-acquired pneumonia and positive blood culture. Four study groups were formed according to presence and/or absence of TP and significant decrease in platelet count. These groups were also studied for their association with mortality and LOS.

RESULTS

Both ≥30% decrease in platelets and TP (58.3% and 25% of patients, respectively) were associated with higher mortality and longer LOS (P<0.0001). Both have association also with infection. There was a trend of increased mortality with higher TP grade. Grade 4 TP was significantly associated with increased LOS (P=0.0001). When compared with neither group, groups with positive significant decrease were associated with higher mortality and LOS, even in the absence of TP.

CONCLUSIONS

We can use the NCI-CTC for classification of TP, which would enable the standardization of TP grading system. A ≥30% decrease in platelet count, even without TP, is a prognostic risk marker for mortality, morbidity, and LOS.

[Management of bleeding disorders in intensive care medicine]

Bleeding disorders are frequent in intensive care medicine, the most common form being acquired. Trauma, gastrointestinal bleeding, liver failure, hematologic malignancies, and adverse drug reactions play an important role. Moderate to severe hereditary bleeding disorders are usually known prior to the acute disease state, while mild hereditary forms may manifest for the first time in association with the acute stress condition. Generally, proper history taking and structured observation are decisive in order to conduct an appropriate diagnostic workup and initiate logical hemostatic management. One cannot always wait for laboratory results during continuous blood loss or conditions such as hypothermia and acidosis. In such cases, pathophysiological extrapolation of expected hemostatic disturbances is essential for timely hemostatic management.

[The platelet and its challenges]

Thrombocytopenia is frequently observed in intensive care medicine, and it is associated with increased mortality. The causes of thrombocytopenia are manifold and several conditions may occur simultaneously so that an exact correlation with a single etiology may be difficult. The present case report demonstrates the importance of an appropriate pathophysiological and clinical consideration in order to avoid misdiagnoses and inappropriate management.

Thrombocytopenia in the pediatric burn patient

Thrombocytopenia is initially seen in patients with burn injury as a transient occurrence during the first week after injury. Subsequent decreases occur later in the course of treatment and are commonly due to sepsis, dilutional effects, and medication exposure. Although studies have demonstrated that thrombocytopenia in the critically ill patients is associated with a worse prognosis, there is limited literature as to the significance of thrombocytopenia in the pediatric burn patients. In this study, the authors evaluate the prognostic implications of thrombocytopenia in the pediatric burn patients. They performed a 5-year retrospective chart of patients aged 18 years or younger with burns >20% TBSA admitted to their institution. Data collected included patient demographics, burn etiology and %TBSA involvement, length of stay, pertinent laboratory values, and in-hospital morbidity and mortality. Of the 187 patients studied, thrombocytopenia occurred in 112 patients. Eighty-two percent demonstrated thrombocytopenia within the first week of injury and 18% demonstrated additional episodes of thrombocytopenia after this time. A reactive thrombocytosis occurred in 130 (70%) patients. The incidence of thrombocytopenia could not be attributed to age, gender, or burn etiology. However, patients with thrombocytopenia were more likely to have inhalation injury and extensive TBSA involvement than those without (P < .05). Sepsis was the cause of significant thrombocytopenia after the first week of hospitalization. Of the 187 patients, 14 died (7%). The incidence of thrombocytopenia in survivors and nonsurvivors was statistically significant in that nonsurvivors demonstrated a more profound drop in platelet count during the first week after injury and had a more depressed platelet recovery curve than survivors. The authors conclude that the early development of thrombocytopenia with depressed thrombocytosis in the pediatric burn patient is associated with increased mortality risk and is influenced by the extent of burn, inhalation injury, and the development of sepsis.

Effect of the intensity of continuous renal replacement therapy in patients with sepsis and acute kidney injury: a single-center randomized clinical trial

INTRODUCTION

Acute kidney injury (AKI) is a major complication in patients with sepsis and is an independent predictor of mortality. However, the optimal intensity of renal replacement therapy for such patients is still controversial.

METHODS

From 1 January 2004 to 30 September 2009, we randomly assigned 280 patients with sepsis and AKI to continuous renal replacement therapy by high-volume hemofiltration (50 mL/kg/h, HVHF) or extra high-volume hemofiltration (85 mL/kg/h, EHVHF). The primary study outcome was death from any cause within 28, 60 and 90 days. Results were analyzed by univariate and multivariate methods and by Kaplan-Meier survival curves.

RESULTS

A total of 141 patients were given EHVHF and 139 were given HVHF. The two groups had similar baseline characteristics and received treatment for an average of 9.38 days (EHVHF group) and 8.88 days (HVHF group). There were no significant differences between the groups in number of deaths at 28, 60 or 90 days. There were also no differences between the groups in renal outcome of survivors at 90 days. Multivariate analysis indicated that inotropic support by norepinephrine, time in hospital of >7 days, blood platelet count <8 × 10(9)/L, Acute Physiological and Chronic Health Evaluation (APACHE) II score >25, total bilirubin >100 μmol/L, prothrombin time >18 s, serum creatinine <250 μmol/L and blood urea nitrogen >20 mmol/L were independent risk factors for death at 90 days after initiation of renal replacement therapy.

CONCLUSIONS

In patients with sepsis and AKI, increasing the intensity of renal replacement therapy from 50 (HVHF) to 85 mL/kg/h (EHVHF) had no effect on survival at 28 and 90 days.

Coagulation biomarkers in critically ill patients

This article discusses coagulation biomarkers in critically ill patients where coagulation abnormalities occur frequently and may have a major impact on the outcome. An adequate explanation for the cause is important, since many underlying disorders may require specific treatment and supportive therapy directed at the underlying condition. Deficiencies in platelets and coagulation factors in bleeding patients or patients at risk for bleeding can be achieved by transfusion of platelet concentrate or plasma products, respectively. Prohemostatic treatment may be beneficial in case of severe bleeding, whereas restoring physiological anticoagulant pathways may be helpful in patients with sepsis and disseminated intravascular coagulation.

A Difficult Diagnosis Case of Prolonged Thrombocytopenia With Sepsis and Disseminated Intravascular Coagulation

A 19-year-old male was admitted because of the trauma due to sepsis-induced disseminated intravascular coagulation (DIC) and multiple organ failure (MOF). We treated with antibiotics, danaparoid, and continuous hemodiafiltration (CHDF). Once he recovered, but after several days, he had septic shock and MOF again. With treatment, the inflammation and MOF improved but the platelet count was less than 1.0 × 10 4/μL. Because of the usage of heparin, we suspected heparin-induced thrombocytopenia (HIT) and measured the HIT antibody and a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13). Heparin-induced thrombocytopenia antibody was positive in the second sepsis but negative in the first sepsis. ADAMTS13 activity was low in both sepses. After stopping CHDF and the usage of heparin, his platelet count improved. Thrombocytopenia is the common and occasional condition for DIC. Heparin-induced thrombocytopenia and thrombotic thrombocytopenic purpura is rare but they must be ruled out in thrombocytopenia with nontypical clinical course, and the assays for HIT antibody and ADAMTS13 activity are useful tools.

Predictive factors of advanced interventional procedures in a multicentre severe postpartum haemorrhage study

PURPOSE

Severe postpartum haemorrhage (SPPH) is the leading cause of peripartum hysterectomy and maternal death. There are no easily measurable parameters that indicate the failure of medical therapy and the need for an advanced interventional procedure (AIP) to stop genital tract bleeding. The aim of the study was to define factors predictive of the need for an AIP in the management of emergent PPH.

METHODS

The study included two phases: (1) an initial retrospective study of 257 consecutive patients with SPPH, allowing the determination of independent predictors of AIP, which were subsequently grouped in a predictive score, followed by (2) a multicentre study of 239 patients admitted during 2007, designed to validate the score. The main outcome measure was the need for an AIP, defined as uterine artery embolization, intraabdominal packing, arterial ligation or hysterectomy.

RESULTS

Abnormalities of placental implantation, prothrombin time <50% (or an International Normalized Ratio >1.64), fibrinogen <2 g/l, troponin detectable, and heart rate >115 bpm were independently predictive of the need for an AIP. The SPPH score included each of the five predictive factors with a value of 0 or 1. The greater the SPPH score, the greater the percentage of patients needing an AIP (11% for SPPH 0, to 75% for SPPH ≥2). The AUC of the ROC curve of the SPPH score was 0.80.

CONCLUSIONS

We identified five independent predictors of the need for an AIP in patients with SPPH and persistent bleeding. Using these predictors in a single score could be a reliable screening tool in patients at risk of persistent genital tract bleeding and needing an AIP.

Systemic versus localized coagulation activation contributing to organ failure in critically ill patients

In the pathogenesis of sepsis, inflammation and coagulation play a pivotal role. Increasing evidence points to an extensive cross-talk between these two systems, whereby inflammation not only leads to activation of coagulation but coagulation also considerably affects inflammatory activity. The intricate relationship between inflammation and coagulation may not only be relevant for vascular atherothrombotic disease in general but has in certain clinical settings considerable consequences, for example in the pathogenesis of microvascular failure and subsequent multiple organ failure, as a result of severe infection and the associated systemic inflammatory response. Molecular pathways that contribute to inflammation-induced activation of coagulation have been precisely identified. Pro-inflammatory cytokines and other mediators are capable of activating the coagulation system and downregulating important physiological anticoagulant pathways. Activation of the coagulation system and ensuing thrombin generation is dependent on an interleukin-6-induced expression of tissue factor on activated mononuclear cells and endothelial cells and is insufficiently counteracted by physiological anticoagulant mechanisms and endogenous fibrinolysis. Interestingly, apart from the overall systemic responses, a differential local response in various vascular beds related to specific organs may occur.

Evidence of disseminated intravascular coagulation in a hemorrhagic fever with renal syndrome-scoring models and severe illness

BACKGROUND

Viral hemorrhagic fevers (VHF) are considered to be a serious threat to public health worldwide with up to 100 million cases annually. The general hypothesis is that disseminated intravascular coagulation (DIC) is an important part of the pathogenesis. The study objectives were to study the variability of DIC in consecutive patients with acute hemorrhagic fever with renal syndrome (HFRS), and to evaluate if different established DIC-scores can be used as a prognostic marker for a more severe illness.

METHOD AND FINDINGS

In a prospective study 2006-2008, data from 106 patients with confirmed HFRS were analyzed and scored for the presence of DIC according to six different templates based on criteria from the International Society on Thrombosis and Haemostasis (ISTH). The DIC-scoring templates with a fibrinogen/CRP-ratio were most predictive, with predictions for moderate/severe illness (p<0.01) and bleeding of moderate/major importance (p<0.05). With these templates, 18.9-28.3% of the patients were diagnosed with DIC.

CONCLUSIONS

DIC was found in about one fourth of the patients and correlated with a more severe disease. This supports that DIC is an important part of the pathogenesis in HFRS. ISTH-scores including fibrinogen/CRP-ratio outperform models without. The high negative predictive value could be a valuable tool for the clinician. We also believe that our findings could be relevant for other VHFs.

Defects in coagulation encountered in small animal critical care

Critically ill small animals are at risk for developing coagulation abnormalities. The processes of inflammation and coagulation are intertwined, and severe inflammation can lead to disturbances of coagulation. Severe coagulation dysfunction is associated with increased morbidity and mortality. Pathophysiology, diagnosis, and treatment of coagulation dysfunction are discussed. Defects in coagulation in small animal patients are complex and a consensus on diagnosis and treatment has yet to be reached.

Beyond thrombosis: the versatile platelet in critical illness

Sepsis, acute lung injury, and ARDS contribute substantially to the expanding burden of critical illness within our ICUs. Each of these processes is characterized by a myriad of injurious events, including apoptosis, microvascular dysfunction, abnormal coagulation, and dysregulated host immunity. Only recently have platelets--long considered merely effectors of thrombosis--been implicated in inflammatory conditions and the pathobiology of these disease processes. A growing body of evidence suggests a prominent role for maladaptive platelet activation and aggregation during sepsis and ARDS and has begun to underscore the pluripotential influence of platelets on outcomes in critical illness. Not only do platelets enhance vascular injury through thrombotic mechanisms but also appear to help orchestrate pathologic immune responses and are pivotal players in facilitating leukocyte recruitment to vulnerable tissue. These events contribute to the organ damage and poor patient outcomes that still plague the care of these high-risk individuals. An understanding of the role of platelets in critical illness also highlights the potential for both the development of risk stratification schema and the use of novel, targeted therapies that might alter the natural history of sepsis, acute lung injury, and ARDS. Future studies of adenosine, platelet polyphosphates, and the platelet transcriptome/proteome also should add considerably to our ability to unravel the mysteries of the versatile platelet.

The septic milieu triggers expression of spliced tissue factor mRNA in human platelets

BACKGROUND

Activated platelets have previously-unrecognized mechanisms of post-transcriptional gene expression that may influence hemostasis and inflammation. A novel pathway involves splicing of pre-mRNAs in resting platelets to mature, translatable mRNAs in response to cellular activation.

OBJECTIVES

We asked if bacterial products and host agonists present in the septic milieu induce tissue factor pre-mRNA splicing in platelets from healthy subjects. In parallel, we asked if spliced tissue factor (TF) mRNA is present in platelets from septic patients in a proof-of-principle analysis.

PATIENTS/METHODS

TF pre-mRNA and mRNA expression patterns were characterized in platelets from septic patients and in platelets isolated from healthy subjects activated with bacteria, toxins and inflammatory agonists. Procoagulant activity was also measured.

RESULTS AND CONCLUSIONS

Live bacteria, staphylococcal α-toxin and lipopolysaccharide (LPS) induced TF pre-mRNA splicing in platelets isolated from healthy subjects. Toxin-stimulated platelets accelerated plasma clotting, a response that was blocked by a previously-characterized splicing inhibitor and by an anti-tissue factor antibody. Platelets from septic patients expressed spliced TF mRNA, whereas it was absent from unselected and age-matched control subjects. Tissue factor-dependent procoagulant activity was elevated in platelets from a subset of septic patients. Thus, bacterial and host factors induce splicing of TF pre-mRNA, expression of TF mRNA and tissue factor-dependent clotting activity in human platelets. TF mRNA is present in platelets from some septic patients, indicating that it may be a marker of altered platelet phenotype and function in sepsis and that splicing pathways are induced in this syndrome.

Eosinopenia, an early marker of increased mortality in critically ill medical patients

PURPOSE

Inflammatory markers may have a role in predicting severity of illness of intensive care unit (ICU) patients. The aim of this study is to determine whether low eosinophil count can predict 28-day mortality in medical ICU.

METHODS

A prospective study over a 4-month period. To evaluate the prognosis information provided by eosinophil count, we compared the variations in eosinophil count from ICU admission to seventh day between patients who survived and those who died. The best cutoff value was chosen using Younden's index for identification of patients with high risk of mortality. The patient outcome was 28-day mortality.

RESULTS

A total of 200 patients were eligible. Overall 28-day ICU mortality was 28% (n = 56). At ICU admission, the median eosinophil count was significantly different in survivors [30 cells/mm³; interquartile range (IQR), 0-100 cells/mm³] and nonsurvivors (0 cells/mm³; IQR, 0-30 cells/mm³; P = 0.004). Absolute eosinophil counts remained significantly lower in nonsurvivors from admission to seventh day. The 28-day mortality was significantly higher in patients with eosinopenia <40 cells/mm(3) (P = 0.011). Multivariate analysis by Cox model with time-dependent covariates demonstrated that eosinophil count <40 cells/mm(3) [hazard ratio (HR), 1.85; 95% confidence interval (CI), 1.01-3.42; P = 0.046], high Acute Physiology and Chronic Health Evaluation (APACHE) II score (HR, 1.08; 95% CI, 1.01-1.14; P = 0.014), high Sequential Organ Failure Assessment (SOFA) score (HR, 1.14; 95% CI, 1.03-1.25; P = 0.008), and use of mechanical ventilation (HR, 27.48; 95% CI, 12.12-62.28; P < 0.001) were independent predictors of 28-day all-cause mortality.

CONCLUSION

This study suggests the possibility to use eosinophil cell count at admission and during the first 7 days as a prognosis marker of mortality in medical ICU.

Safety and antithrombotic efficacy of moderate platelet count reduction by thrombopoietin inhibition in primates

Most heart attacks and strokes are caused by blood clots (thrombi) that block the vasculature. Because disease-causing arterial thrombosis depends on blood platelets, platelet inhibitors such as aspirin and clopidogrel effectively decrease the risk of thrombosis; however, they also impair platelet-dependent hemostasis that staunches bleeding from wounds and can therefore produce excessive bleeding. Experimental studies show that a reduction in the number of platelets also inhibits thrombosis, but these treatments also interfere with platelet function. Because normal hemostasis requires that the platelet concentration remain within a physiological range in the circulation, we evaluated whether lowering the number of circulating platelets--but only to a value still within the normal range--by inhibiting platelet formation in the bone marrow inhibits acute thrombogenesis in baboons. We reduced the platelet count with an inhibitor against the megakaryocyte-promoting hormone thrombopoietin and then showed that experimental occlusive thrombogenesis on collagen-coated vascular grafts was reduced, without impairment of primary hemostasis. These results suggest that suppressing platelet production without interfering with the hemostatic function of platelets may offer a safe alternative to current therapies for prevention of stroke and heart attack triggered by blood clotting.

Mitral valve repair in a patient with thrombocytopenia-absent radius syndrome: case report

Thrombocyte level and functions are vital factors during cardiac surgery. Thrombocytopenia-absent radius syndrome (TAR) is a rare genetic disorder consisting of skeletal abnormalities and thrombocytopenia. In this report, we present the management strategy for a 23-year-old female patient with TAR syndrome who underwent mitral valve repair.

Predictors of mortality of Acinetobacter baumannii infections: A 2-year prospective study in a Greek surgical intensive care unit

BACKGROUND

Nosocomial infections are a frequent and continuously increasing problem worldwide, have a rapidly increasing multidrug resistance to antibiotics, and are associated with significant morbidity and mortality.

OBJECTIVE

Our objectives were to evaluate Acinetobacter baumannii infection incidence in our surgical intensive care unit (SICU), the clinical features and outcome of these patients, and, particularly, to investigate predictors of A baumannii infection-related mortality.

METHODS

Ours was a prospective study of all patients with ICU-acquired A baumannii infection from January 1, 2006, to December 31, 2007.

RESULTS

Among 680 patients, 60 (8.8%) sustained A baumannii infection. Mean age was 68.4 ± 6.2 years, Acute Physiology and Chronic Health Evaluation (APACHE) II score on SICU admission 20.6 ± 8.1 and Sequential Organ Failure Assessment (SOFA) score on infection day 9.5 ± 4.2 (women: 50%). Multidrug resistance, morbidity, and mortality were 45%, 65%, and 46.6% (n = 28), respectively. In multivariate analysis, age (P = .03; odds ratio [OR], 1.13; 95% confidence interval [CI]: 1.018-1.259), acute renal failure (P = .001; OR, 17.9; 95% CI: 6.628-75.565), and thrombocytopenia (P = .03; OR, 26.4; 95% CI: 1.234-56.926) complicating the infection and subsequent Enterococcus faecium bacteremia (P = .01; OR, 3.5; 95% CI: 1.84-6.95) were mortality predictors.

CONCLUSION

A baumannii infections are frequent and associated with high drug multiresistance, morbidity, and mortality. Age, renal failure, thrombocytopenia, and subsequent E faecium bacteremia were predictors of A baumannii infection-associated mortality.