Administration Of Transfusions Research Articles

The Association of Peri-Procedural Blood Transfusion with Morbidity and Mortality in Patients Undergoing Percutaneous Lower Extremity Vascular Interventions: Insights from BMC2 VIC.

ObjectiveTo determine the predictors of periprocedural blood transfusion and the association of transfusion on outcomes in high risk patients undergoing endoluminal percutaneous vascular interventions (PVI) for peripheral arterial disease.Methods/ResultsBetween 2010–2014 at 47 hospitals participating in a statewide quality registry, 4.2% (n = 985) of 23,273 patients received a periprocedural blood transfusion. Transfusion rates varied from 0 to 15% amongst the hospitals in the registry. Using multiple logistic regression, factors associated with increased transfusion included female gender (OR = 1.9; 95% CI: 1.6–2.1), low creatinine clearance (1.3; 1.1–1.6), pre-procedural anemia (4.7; 3.9–5.7), family history of CAD (1.2; 1.1–1.5), CHF (1.4; 1.2–1.6), COPD (1.2; 1.1–1.4), CVD or TIA (1.2; 1.1–1.4), renal failure CRD (1.5; 1.2–1.9), pre-procedural heparin use (1.8; 1.4–2.3), warfarin use (1.2; 1.0–1.5), critical limb ischemia (1.7; 1.5–2.1), aorta-iliac procedure (1.9; 1.5–2.5), below knee procedure (1.3; 1.1–1.5), urgent procedure (1.7; 1.3–2.2), and emergent procedure (8.3; 5.6–12.4). Using inverse weighted propensity matching to adjust for confounders, transfusion was a significant risk factor for death (15.4; 7.5–31), MI (67; 29–150), TIA/stroke (24; 8–73) and ARF (19; 6.2–57). A focused QI program was associated with a 28% decrease in administration of blood transfusion (p = 0.001) over 4 years.ConclusionIn a large statewide PVI registry, post procedure transfusion was highly correlated with a specific set of clinical risk factors, and with in-hospital major morbidity and mortality. However, using a focused QI program, a significant reduction in transfusion is possible.

Determination of human blood type using image processing techniques

Abstract The undertaking of pre-transfusion tests is an essential task before the administration of a blood transfusion. It is through these tests that it is determined the blood profile compatible with the blood transfusion receiver. In certain emergency situations there is no time for performing the necessary tests with the available commercial systems and therefore it is administered the blood type O negative. This blood type is considered the universal donor, in the transfusion context, as it presents a lower risk of incompatibilities. However, even with the universal donor, transfusion reactions can occur in case of patients with different blood types. These incompatibilities can cause the death of the patient, depending on the severity of his or her health condition. This paper presents an electronic system and an interface application, able to perform all pre-transfusion tests quickly, easily, in safe conditions, and with high reliability, even in remote locations. To this end, the system is based on the plate test procedure and is of small dimensions being easy to carry. Another advantage of this system is its low cost that will be a factor of competition in the market. Moreover, the data acquisition is based on image processing techniques to obtain results, and it was developed using C# programming language. The user interface was developed with Xaml programming language as requirements of usability impose being compatible with a variety of platforms including computers, tablets, and smart phones.

A Rare Cause of Massive Upper Gastrointestinal Bleeding

Question: A 58-year-old woman was admitted with multiple episodes of melena. The patient had a history of surgery for colon cancer 7 years ago and underwent radiofrequency ablation for metastatic liver cancer 4 year ago. She was treated in another hospital for massive hematemesis and a transient loss of consciousness and was relieved after blood transfusion and proton pump inhibitor administration 5 days ago. Physical examination showed an anemic appearance. Laboratory tests revealed a low level of hemoglobin (73 g/L). An emergency gastroscopy in our department revealed a bleeding gastric ulcer, blood-like fluid effusion in stomach lumen (Figure A). What is the most likely cause of upper gastrointestinal (GI) bleeding in this patient? See the Gastroenterology web site (www.gastrojournal.org) for more information on submitting your favorite image to Clinical Challenges and Images in GI. Abdominal enhanced computed tomography (CT) scanning revealed multiple metastatic tumors in the liver (Figure B, black arrows) and the body and tail of pancreas (Figure B, white arrow). Importantly, invasion of stomach wall by the neighboring pancreatic tumors led to the formation of a gastric fistula, through which the contrast media was leaking into stomach lumen. CT angiography and vascular reconstruction further confirmed tumor erosion of the splenic artery and the formation of splenic artery pseudoaneurysm (SAPA) as well as tumor–gastric fistula (Figure C, D). Digital subtraction angiography also demonstrated extravasation of contrast media from SAPA through the fistula (Figure E). The patient was treated by splenic artery embolization. Postoperative angiography revealed complete blockade of the SAPA (Figure F). An enhanced CT examination on the following day showed no sign of active bleeding. The patient recovered uneventfully and was discharged without any symptoms over a 6-month follow-up period. Splenic artery aneurysms are the most common visceral artery aneurysms and are broadly classified as true aneurysms and pseudoaneurysms.1Illuminati G. LaMuraglia G. Nigri G. Surgical repair of an aberrant splenic artery aneurysm: report of a case.Ann Vasc Surg. 2007; 21: 216-218Abstract Full Text Full Text PDF PubMed Scopus (22) Google Scholar Causes of SAPA include pancreatitis (52%), abdominal trauma (29%), iatrogenic and postoperative causes (3%), and peptic ulcer (2%).2Wang J. Wang B. Chen D.F. An unusual cause of recurrent massive upper gastrointestinal bleeding.Gastroenterology. 2012; 143: 542Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar Metastatic pancreatic tumor is rare, accounting for only 2% of all pancreatic tumors.3Lee C.W. Wu R.C. Hsu J.T. et al.Isolated pancreatic metastasis from rectal cancer: a case report and review of literature.World J Surg Oncol. 2010; 8: 26Crossref Scopus (15) Google Scholar To the best of our knowledge, SAPA caused by metastatic pancreatic tumor has not yet been reported. In the present case, the complicated patient history and endoscopic findings make the diagnosis difficult. In this scenario, enhanced CT examination and vascular reconstruction are beneficial for the diagnosis of SAPA. Superselective splenic artery embolization represents an effective approach to treat these patients with high surgical risk.

Retrospective evaluation of the effect of red blood cell product age on occurrence of acute transfusion-related complications in dogs: 210 cases (2010-2012).

To determine whether red blood cell (RBC) product age influences the occurrence of acute transfusion-related complications and mortality in dogs. The hypothesis was that acute transfusion-related complications and mortality would increase with age of product. Retrospective study (2010-2012). University teaching hospital. Two hundred and ten clinical canine patients. None. Medical records were reviewed for dogs receiving RBC-containing products. Patient signalment; reason for transfusion; product type, dose, age, and source; pretransfusion compatibility; rate, route, and method of administration; administration of multiple transfusions; underlying disease; occurrence of transfusion-related complications (eg, fever, hemolysis, gastrointestinal distress, cardiovascular, neurologic, and respiratory complications); various hematologic parameters; and survival were recorded. Data were analyzed for association between potential risk factors and occurrence of transfusion-related complications as well as between transfusion-related complications and survival. Of 333 transfusion events in 210 patients, 84 transfusion-related complications occurred. Fever was most common (41/333), followed by hemolysis (21/333). For every additional day of product age, the odds of hemolysis increased significantly (odds ratio, 1.11; 95% confidence interval, 1.06-1.16; P < 0.0001). Transfusion-related complications when considered as a whole were associated with higher dose of product, longer duration of administration per transfusion event, and immune-mediated disease, but not with source of product or general category of anemia. Administration rate was significantly slower in patients with febrile transfusion-related complications (P < 0.0001). Product age was not associated with increased mortality. Age of stored RBC products is associated with increased risk of transfusion-related hemolysis, but not with fever. Prospective clinical studies evaluating the influence of storage duration on development of in vitro versus in vivo hemolysis are warranted.

The role of thromboelastography in predicting bleeding risk and guiding the administration of platelet transfusions in hematological patients: a cohort study.

The purpose of this study was to assess the accuracy of the parameters used in conventional hemostatic testing and thromboelastography (TEG) in predicting bleeding risk in patients with hematologic diseases. Patients diagnosed with a hematologic disease were divided into bleeding (n = 125) and non-bleeding (n = 509) groups according to clinical signs and symptoms. Several parameters were measured in all patients via traditional hemostatic testing and TEG, including platelet counts (PLT) and maximum amplitude (MA). The sensitivity and specificity of each parameter for predicting bleeding risk were determined via receiver operating characteristic curves. PLT had a sensitivity of 81.1% and a specificity of 74.4%, and MA had a sensitivity of 74.7% and a specificity of 72.0%. Specificity was higher for both parameters together (77.6%) than for either alone (P < 0.01). In a subgroup analysis of patients with PLT < 20 × 10(9)/L, sensitivity was higher for both parameters together (84.6%) than for either alone (P = 0.003). Although all parameters evaluated predicted bleeding risk, PLT and MA were especially accurate. We suggest that the combination of PLT and MA better assesses bleeding risk than do other parameters and that the use of this metric may help to guide decisions regarding platelet transfusion in patients with thrombocytopenic hematologic diseases.

Effect of Perioperative Goal-Directed Hemodynamic Resuscitation Therapy on Outcomes Following Cardiac Surgery: A Randomized Clinical Trial and Systematic Review.

To evaluate the effects of goal-directed therapy on outcomes in high-risk patients undergoing cardiac surgery. A prospective randomized controlled trial and an updated metaanalysis of randomized trials published from inception up to May 1, 2015. Surgical ICU within a tertiary referral university-affiliated teaching hospital. One hundred twenty-six high-risk patients undergoing coronary artery bypass surgery or valve repair. Patients were randomized to a cardiac output-guided hemodynamic therapy algorithm (goal-directed therapy group, n = 62) or to usual care (n = 64). In the goal-directed therapy arm, a cardiac index of greater than 3 L/min/m was targeted with IV fluids, inotropes, and RBC transfusion starting from cardiopulmonary bypass and ending 8 hours after arrival to the ICU. The primary outcome was a composite endpoint of 30-day mortality and major postoperative complications. Patients from the goal-directed therapy group received a greater median (interquartile range) volume of IV fluids than the usual care group (1,000 [625-1,500] vs 500 [500-1,000] mL; p < 0.001], with no differences in the administration of either inotropes or RBC transfusions. The primary outcome was reduced in the goal-directed therapy group (27.4% vs 45.3%; p = 0.037). The goal-directed therapy group had a lower occurrence rate of infection (12.9% vs 29.7%; p = 0.002) and low cardiac output syndrome (6.5% vs 26.6%; p = 0.002). We also observed lower ICU cumulative dosage of dobutamine (12 vs 19 mg/kg; p = 0.003) and a shorter ICU (3 [3-4] vs 5 [4-7] d; p < 0.001) and hospital length of stay (9 [8-16] vs 12 [9-22] d; p = 0.049) in the goal-directed therapy compared with the usual care group. There were no differences in 30-day mortality rates (4.8% vs 9.4%, respectively; p = 0.492). The metaanalysis identified six trials and showed that, when compared with standard treatment, goal-directed therapy reduced the overall rate of complications (goal-directed therapy, 47/410 [11%] vs usual care, 92/415 [22%]; odds ratio, 0.40 [95% CI, 0.26-0.63]; p < 0.0001) and decreased the hospital length of stay (mean difference, -5.44 d; 95% CI, -9.28 to -1.60; p = 0.006) with no difference in postoperative mortality: 9 of 410 (2.2%) versus 15 of 415 (3.6%), odds ratio, 0.61 (95% CI, 0.26-1.47), and p = 0.27. Goal-directed therapy using fluids, inotropes, and blood transfusion reduced 30-day major complications in high-risk patients undergoing cardiac surgery.

Predictors of early versus late mortality in pelvic trauma patients.

BackgroundRisks of predicting time-related in-hospital mortality varies in pelvic trauma patients. We aim to identify potential independent risks predictive of time-related (early versus late) mortality among pelvic trauma patients.MethodsLocal trauma registry data from 2004 through 2013 were reviewed. Mortality causes and timing of death were investigated. Multivariate logistic regression identified independent risks predictive of early versus late mortality in pelvic trauma patients while adjusting for patient demographics (age, sex, race), clinical variables (initial vital signs, mental status, injury severity, associated injuries, comorbidities), and hospital outcomes (surgical interventions, crystalloid resuscitations, blood transfusions).ResultsWe retrospectively collected data on 1566 pelvic trauma patients with a mortality rate of 9.96 % (156/1566). Approximately 74 % of patients died from massive hemorrhage within the first 24 h of hospitalization (early mortality). Revised trauma score (RTS), injury severity score (ISS), initial hemoglobin, direct transfer to operating room, and blood transfusion administration in the Emergency Department were considered independent risk factors predictive of early mortality. Age, ISS, and Glasgow Coma Scale (GCS) were deemed risk factors predictive of death after 24 h (late mortality).DiscussionGiven the fact of a substantial number of patients died within the first 24 h of hospital arrival, it is reasonable to consider the first 24 h of hospitalization as the appropriate window within which early mortality may be expected to occur in pelvic trauma patients. The risk factors associated with massive hemorrhage were strong predictors of early mortality, whereas late mortality predictors were more closely linked with comorbidities or in-hospital complications.ConclusionsWhile risk factors predictive of early versus late mortality vary, ISS seems to predict both early and late mortality accurately in pelvic trauma patients.

SHOCK VOLUME: A PATIENT-SPECIFIC INDEX THAT PREDICTS TRANSFUSION REQUIREMENTS AND ORGAN DYSFUNCTION IN MULTIPLY INJURED PATIENTS.

Multiply injured patients (MIPs) in hemorrhagic shock develop oxygen debt which causes organ dysfunction and can lead to death. We developed a noninvasive patient-specific index, Shock Volume (SV), to quantify the magnitude of hypoperfusion. SV integrates the magnitude and duration that incremental shock index values are elevated above known thresholds of hypoperfusion using serial individual vital sign data. SV can be monitored in real time to assess ongoing hypoperfusion. The goal of this study was to determine how SV corresponded to transfusion requirements and organ dysfunction in a retrospective cohort of 74 MIPs. We measured SV in 6-h increments for 48 h after injury in multiply injured adults (18-65; Injury Severity Score ≥18). Patients who had accumulated 40 units of SV within 6 h of injury and 100 units of SV within 12 h of injury were at high risk for requiring massive transfusion or multiple critical administration transfusions. SV measurements were equally sensitive and specific as compared with base deficit values in predicting transfusions. SV measurements at 6 h after injury stratified patients at risk for multiple organ failure determined by Denver scores. In addition, SV values corresponded to the magnitude of organ failure determined by Sequential Organ Failure Assessment scores. SV is a patient-specific index that can be quantified in real time in critically injured patients. It is a surrogate for cumulative hypoperfusion and it predicts high-volume transfusions and organ dysfunction.

Association between Perioperative Blood Transfusions and Clinical Outcomes in Patients Undergoing Bladder Cancer Surgery: A Systematic Review and Meta-Analysis Study

Background. Perioperative blood transfusions are associated with poor survival in patients with solid tumors including bladder cancer. Objective. To investigate the impact of perioperative blood transfusions on oncological outcomes after radical cystectomy. Design. Systematic review and meta-analysis. Setting and Participants. Adult patients who underwent radical cystectomy for bladder cancer. Intervention. Packed red blood cells transfusion during or after radical cystectomy for bladder cancer. Outcome Measurements and Statistical Analysis. Recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS). We calculated the pooled hazard ratio (HR) estimates and 95% confidence intervals by random and fixed effects models. Results and Limitation. Eight, seven, and five studies were included in the OS, CSS, and RFS analysis, respectively. Blood transfusions were associated with 27%, 29%, and 12% reduction in OS, CSS, and RFS, respectively. A sensitivity analysis supported the association. This study has several limitations; however the main problem is that it included only retrospective studies. Conclusions. Perioperative BT may be associated with reduced RFS, CSS, and OS in patients undergoing RC for BC. A randomized controlled study is needed to determine the causality between the administration of blood transfusions and bladder cancer recurrence.

再生不良性貧血による高度な汎血球減少を伴った肝細胞癌に対して治療介入を行った2例

Aplastic anemia (AA) is characterized by bone marrow hypoplasia and peripheral pancytopenia and is associated with increased susceptibility to infection and bleeding tendency. Here, we describe two patients with hepatocellular carcinoma (HCC) exhibiting severe pancytopenia caused by AA. They were successfully treated by transarterial embolization (TAE). To reduce the risk of complications, both component transfusion and intravenous administration of antibiotics were performed. Although they required repeated TAE after several recurrences, the tumors were eventually almost controlled. In conclusion, HCC was successfully treated by TAE in patients with severe pancytopenia caused by AA. In such cases, close cooperation with hematologists is required to improve long-term prognosis.

Number of severe bleeding complications according to classification used: Is unified classification of bleeding complications really necessary?

To compare the number of severe periprocedural bleeding complications from the total number of bleeding complications associated with diagnostic selective coronary angiography or percutaneous coronary intervention (PCI) when using different classifications (TIMI, GUSTO, PLATO, BARC) and to relate these classifications to real hemodynamic status of evaluated patients. We analyzed data from 106 patients who underwent invasive procedure for ischemic heart disease (selective coronary angiography/PCI) and suffered from any type of bleeding complication. The number of bleeding according to impacts on hemodynamic status and consequent treatment shows that 54.7% of all bleedings did not need any specific therapy. Bleeding leading to death, hemorrhagic shock, hemodynamic instability, administration of blood transfusion, surgical procedure and local treatment occurred in 6.6%, 1.9%, 5.7%, 14.2%, 2.8%, and 14.2%, respectively. The results comparing bleeding classifications demonstrate that the rate of severe bleeding complications may increase up to 4 times when different classifications are used on the same group of patients (TIMI 9.4%, GUSTO 15.1%, PLATO 39.2% and BARC 35.9%). The power of association between severe bleeding determined by these classifications and real hemodynamic compromise using Kendall's tau-c correlation is -0.4106 (95% CI -0.599 to -0.222), -0.5355 (95% CI -0.718 to -0.353), -0.5513 (95% CI -0.729 to -0.374) and -0.7552 (95% CI -0.897 to -0.612) for TIMI, GUSTO, PLATO and BARC, respectively. The data show significant dependence of percentage of severe periprocedural bleeding complications on selected classification. The strongest association between severe bleeding and real hemodynamic status was found for BARC classification as this classification seems to be promising for future general use.

Comparison of different platelet count thresholds to guide administration of prophylactic platelet transfusion for preventing bleeding in people with haematological disorders after myelosuppressive chemotherapy or stem cell transplantation.

Comparison of different platelet count thresholds to guide administration of prophylactic platelet transfusion for preventing bleeding in people with haematological disorders after myelosuppressive chemotherapy or stem cell transplantation.

Hospital-acquired Anemia in Critically Ill Dogs and Cats: A Multi-Institutional Study.

BackgroundHospital‐acquired anemia is commonly described in people but limited information currently is available regarding its prevalence in animals.Hypothesis/objectivesAssess the prevalence of hospital‐acquired anemia in hospitalized critically ill dogs and cats, and examine its relationship with phlebotomy practices, transfusion administration, and survival to discharge.AnimalsEight hundred and fifty‐one client‐owned animals (688 dogs and 163 cats).MethodsA multicenter, observational study was conducted in which packed cell volume (PCV) was recorded at the time of admission and on subsequent hospitalization days. Signalment, number of blood samples obtained, underlying disease, whether or not blood products were administered, duration of hospitalization, and survival to discharge were recorded.ResultsAdmission anemia prevalence was 32%, with overall prevalence during the hospitalization period of 56%. The last recorded PCV was significantly lower than the admission PCV for both dogs (admission PCV, 42% [range, 6–67%]; last recorded PCV, 34% [range, 4–64%], P < .0001) and cats (admission PCV, 31% [range, 6–55%]; last recorded PCV, 26% [range, 10–46%], P < .0001). Patients that developed anemia had significantly more blood samples obtained (nonanemic, 5 blood samples [range, 2–54]; anemic, 7 blood samples [range, 2–49], P < .0001). Hospitalized cats were significantly more likely to develop anemia compared to dogs (P < .0001), but anemic dogs were significantly less likely to survive to discharge (P = .0001). Surgical patients were at higher risk of developing hospital‐acquired anemia compared to medical patients (OR, 0.63; 95% CI, 0.4–0.9; P = .01).Conclusions and Clinical RelevanceHospital‐acquired anemia occurred frequently, especially in surgical patients. Additional studies focused on the direct effect of phlebotomy practices on the likelihood of anemia development in hospitalized animals are warranted.

Perioperative stroke in patients undergoing elective spinal surgery: a retrospective analysis using the Japanese diagnosis procedure combination database

BackgroundAlthough a few studies on perioperative stroke following spinal surgery have been reported, differences in the incidence of perioperative stroke among various surgical procedures have not been determined. The purpose of this retrospective analysis was to investigate the incidence of perioperative stroke during hospitalization in patients undergoing elective spinal surgery, and to examine whether the incidence varied according to the surgical procedure.MethodsA retrospective analysis of data from the Diagnosis Procedure Combination database, a nationwide administrative impatient database in Japan, identified 167,106 patients who underwent elective spinal surgery during 2007–2012. Patient information extracted included age, sex, preoperative comorbidity, administration of blood transfusion, length of hospitalization, and type of hospital. Clinical outcomes included perioperative stroke during hospitalization, and in-hospital death.ResultsThe overall incidence of perioperative stroke was 0.22 % (371/167,106) during hospitalization. A logistic regression model fitted with a generalized estimating equation showed perioperative stroke was associated with advanced age, a history of cardiac disease, an academic institution, and resection of a spinal tumor. Patients who underwent resection of a spinal cord tumor (reference) had a higher risk of stroke compared with those undergoing discectomy (odds ratio (OR), 0.29; 95 % confidence interval (CI), 0.14–0.58; p = 0.001), decompression surgery (OR, 0.44; 95 % CI, 0.26–0.73; p = 0.001), or arthrodesis surgery (OR, 0.55; 95 % CI, 0.34–0.90); p = 0.02). Advanced age (≥80 years; OR, 5.66; 95 % CI, 3.10–10.34; p ≤ 0.001), history of cardiac disease (OR, 1.58; 95 % CI, 1.10–2.26; p = 0.01), diabetes (OR, 1.73; 95 % CI, 1.36–2.20; p ≤ 0.001), hypertension (OR, 1.53; 95 % CI, 1.18–1.98; p = 0.001), cervical spine surgery (OR, 1.44; 95 % CI, 1.09–1.90; p = 0.01), a teaching hospital (OR, 1.36; 95 % CI, 1.01–1.82; p = 0.04), and length of stay (OR, 1.008; 95 % CI, 1.005–1.010; p ≤ 0.001) were also risk factors for perioperative stroke.ConclusionsPerioperative stroke occurred in 0.22 % of patients undergoing spinal surgery. Resection of a spinal cord tumor was associated with increased risk of perioperative stroke as well as advanced age, comorbidities at admission, cervical spine surgery, surgery in a teaching hospital, and length of stay.

Fundamental Principles of Cancer Biology: Does It Have Relevance to the Perioperative Period?

Malignant tumors are characterized by their ability to metastasize, which is the main cause of cancer-related mortality. Besides intrinsic alternations in cancer cells, the tumor microenvironment plays a pivotal role in tumor growth and metastasis. Ample evidence suggests that the perioperative period and the excision of the primary tumor can promote the development of metastases and can influence long-term cancer patient outcomes. The role of cancer biology and its impact on the perioperative period are of increasing interest. This review will present evidence regarding fundamental principles of cancer biology, especially tumor microenvironment, and discuss new therapeutic opportunities in the perioperative timeframe. We will also discuss the regulatory signaling that could be relevant to various aspects of surgery and surgical responses, which could facilitate the metastatic process by directly or indirectly affecting malignant tissues and the tumor microenvironment. We address the influences of surgery-related stress, anesthetic and analgesic agents, blood transfusion, hypothermia, and β-adrenergic blockade administration on tumor growth and metastasis. Through an improved understanding of these processes, we will provide suggestions for potential new perioperative approaches aimed at improving treatment outcomes of cancer patients.

Conceitos atuais sobre suporte hemodinâmico e terapia em choque séptico

Severe sepsis and septic shock represent a major healthcare challenge. Much of the improvement in mortality associated with septic shock is related to early recognition combined with timely fluid resuscitation and adequate antibiotics administration. The main goals of septic shock resuscitation include intravascular replenishment, maintenance of adequate perfusion pressure and oxygen delivery to tissues. To achieve those goals, fluid responsiveness evaluation and complementary interventions – i.e. vasopressors, inotropes and blood transfusion – may be necessary. This article is a literature review of the available evidence on the initial hemodynamic support of the septic shock patients presenting to the emergency room or to the intensive care unit and the main interventions available to reach those targets, focusing on fluid and vasopressor therapy, blood transfusion and inotrope administration.

Acute Kidney Injury With Tobramycin-Impregnated Bone Cement Spacers in Prosthetic Joint Infections.

Antibiotic-impregnated bone cement spacer (ACS) with tobramycin ± vancomycin is commonly used in a 2-stage replacement of infected prosthetic joints. This procedure has been associated with development of acute kidney injury (AKI). To determine the incidence and risk factors for AKI after implantation of tobramycin-impregnated ACS. This prospective, observational study evaluated 50 consecutive patients who received tobramycin ACS for first-stage revision of an infected hip or knee arthroplasty from August 2011 to February 2013. AKI was defined as 50% or greater rise in serum creatinine (SCr) from baseline within the first 7 postoperative days (PODs). The incidence of AKI was 20%, with median onset occurring at POD 2 (interquartile range [IQR] = 1-3); patients with AKI had a longer median duration of hospital stay (16 days, IQR = 12-17, vs 10 days, IQR = 8-10; P = 0.03). Serum tobramycin concentrations were significantly higher in the AKI group, peaking on POD 1 (median 1.9 vs 0.9 µg/mL, P = 0.01). Risk factors for nephrotoxicity identified by multivariate analysis were use of bone cement premanufactured with gentamicin (OR = 8.2; 95% CI = 1.1-60; P = 0.04), administration of blood transfusions intraoperatively (OR = 32.5; 95% CI = 2.3-454.3; P = 0.01) and nonsteroidal anti-inflammatory drugs postoperatively (OR = 23.0; 95% CI = 1.3-397.7; P = 0.03). Tobramycin ACS is associated with a high risk of AKI. Measures to minimize AKI risk in the perioperative period include early detection through close monitoring of SCr, avoiding use of premanufactured bone cement containing gentamicin, and avoiding potential nephrotoxins within the first 72 hours postoperatively.

Liberal or Restrictive Transfusion after Cardiac Surgery.

To the Editor: In their article on red-cell transfusion, Murphy et al. (March 12 issue) 1 report substantial nonadherence to treatment in both study groups — one of which had a restrictive threshold for hemoglobin level in red-cell transfusions and one of which had a liberal threshold. Although nonadherence (defined as either the failure to transfuse red cells within 24 hours after a patient’s hemoglobin fell below an assigned threshold or the administration of a transfusion when the hemoglobin level was above the assigned threshold) increases the likelihood of a null result for the primary outcome, it might confound the finding of increased 90-day mortality in the restrictive-threshold group, since patients in that group who received transfusions above the restrictive threshold were assumed to be sicker, whereas patients in the group with a liberal threshold were assumed to be healthier (and hence not receiving transfusions below the liberal threshold). Did the authors observe an increase in mortality in association with nonadherence to treatment in the restrictive-threshold group?

Current concepts on hemodynamic support and therapy in septic shock

Severe sepsis and septic shock represent a major healthcare challenge. Much of the improvement in mortality associated with septic shock is related to early recognition combined with timely fluid resuscitation and adequate antibiotics administration. The main goals of septic shock resuscitation include intravascular replenishment, maintenance of adequate perfusion pressure and oxygen delivery to tissues. To achieve those goals, fluid responsiveness evaluation and complementary interventions – i.e. vasopressors, inotropes and blood transfusion – may be necessary. This article is a literature review of the available evidence on the initial hemodynamic support of the septic shock patients presenting to the emergency room or to the intensive care unit and the main interventions available to reach those targets, focusing on fluid and vasopressor therapy, blood transfusion and inotrope administration.

Could abnormal neutrophil‐platelet interactions and complex formation contribute to oxidative stress and organ failure in cirrhosis?

This pilot study was funded by the Isaac Schapera Research Trust in an award to Jonathan Sturgeon in 2012‐2013. Potential conflict of interest: Dr. Bernal consults for Vital Therapies and Ocera. To the Editor: Susceptibility to developing infection is well recognized in cirrhosis: circulating neutrophil dysfunction, including excessive production of reactive oxygen species (ROS), is a major contributor to innate immune paresis, development of multiorgan failure, and survival.1 Platelets also play a key role in modulating inflammation by interacting with neutrophils, secreting inflammatory mediators, and influencing phagocytosis/apoptosis.2 Here, we report on the results of a pilot study that examined neutrophil‐platelet interactions in patients with cirrhosis and characterized responses when their neutrophils were exposed to healthy platelets simulating platelet transfusion. Neutrophil‐platelet interactions were characterized in 10 patients with stable advanced cirrhosis (9:1 male/female; mean age: 56.5 years; mean Child‐Pugh score: 10) in a paired crossover study with 10 healthy controls (HCs). Neutrophils and platelets were isolated separately and incubated in zero, 50:1, and 100:1 platelet: neutrophil ratios. Neutrophils were stained with anti‐CD16‐PE and anti‐CD11b‐APC‐Cy7 (macrophage‐1 antigen) and analyzed using flow cytometry. Platelets were stained with anti‐CD41a‐APC (glycoprotein IIb/IIIa), and neutrophil‐platelet complexes (NPCs) were identified as staining for CD11b/CD16/CD41a. Neutrophils were stimulated with phorbol myristate acetate, which induces ROS production, which was quantified by conversion of dihydrorhodamine‐123 to rhodamine‐123. Both the amount of ROS production and the number of neutrophils undergoing oxidative burst were measured. After stimulation, samples incubated with healthy platelets had fewer neutrophils undergoing oxidative burst, compared to cirrhotic platelets (P < 0.05, 50:1; P < 0.01, 100:1 ratios; Fig. 1A). The addition of healthy platelets also corresponded with a significant increase in NPCs (P < 0.05, 100:1 ratio; Fig. 1B). Neutrophils that were part of an NPC demonstrated a 3‐fold increase in CD11b expression over the background population of neutrophils (P < 0.01). Circulating NPCs represent a subpopulation of activated neutrophils primed for adhesion, phagocytosis, and intracellular killing,3 which protects against microbial invasion, but paradoxically induces endothelial dysfunction, bystander damage, and end‐organ dysfunction.4Figure 1: Graphs demonstrating the (A) reduction in the number of neutrophils undergoing oxidative burst (OB) with the addition of healthy and cirrhotic platelets and (B) formation of neutrophil‐platelet complexes following addition of platelets. Ratios (50:1 and 100:1) are the platelet: neutrophil ratios incubated. *P < 0.05; **P < 0.01.In summary, neutrophil‐platelet interactions appear, at least in vitro, to contribute toward neutrophil dysfunction in cirrhosis. Therefore, administration of a platelet transfusion before an invasive procedure or during bleeding episodes in patients with cirrhosis could be detrimental by promoting neutrophil activation and increased NPC formation. Further studies are now warranted to assess the in vivo consequences of administration of platelet transfusions in patients with cirrhosis.