Ventilator – Associated Pneumonia: Pathophysiology, Diagnosis, and Treatment

Ventilator Associated Pneumonia (VAP) is a common and important problem in the ICU. It affects approximately 25 % of ICU patients. With the rise of mechanical ventilation throughout the world its occurrence will only increase. Mortality from VAP is in the range of 30-70%. With early diagnosis and treatment the mortality may be decreased. In this review we will discuss the pathophysiology, diagnosis and treatment of VAP. Through proper education and diagnosis we may be able to decrease the incidence of VAP and thereby decrease the complications of this very common problem.


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Loop Diuretics in Acute Oliguric and Pre-renal States

Oliguria is common in critically ill patients, the most common cause being a reduction of the effective intravascular volume. Oliguric patients are almost universally treated with escalating doses of loop diuretics in the hope of increasing urine output. However, in the setting of a reduced effective intravascular volume loop diuretics cause a marked fall in glomerular filtration rate with an acute decline in renal function. In this paper we demonstrate that there is no scientific rationale or clinical evidence to support the use of loop diuretics in patients with oliguria and pre-renal azotemia, prophylactically in patients at risk of developing acute renal failure and in patients with established acute renal failure.


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Henderson-Hasselbalch vs Stewart: Another Acid-Base Controversy

The Henderson-Hasselbalch approach to acid-base physiology and disorders has been the dominant approach for the last 100 years. Over the last 20 years there has been considerable interest in a different approach developed by Peter Stewart. At the center of the controversy around the Stewart approach is replacing the role of bicarbonate with the strong-ion-difference and total weak-acid concentration.The Stewart approach, however, appears to better describe the nature and complexity of the clinical acid-base disorders of the critically ill. The old and the new maybe partially reconciled by combining Stewart’s approach with base-excess. This combination appears to have considerable clinical utility.


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Effectiveness Study of rHuEPO in the ICU

Purpose: To evaluate the clinical outcomes and resource use in ICU patients receiving rHuEPO in a naturalistic setting.
Methods: A retrospective, case-matched (1:2 ratio) study compared patients receiving rHuEPO to a control group. Patients admitted between January 2000 and July 2002 with an ICU length of stay (LOS) ¡Ý3 days were identifi ed by an electronic data repository. Patients, who received rHuEPO prior to ICU admission, had chronic renal failure or were <18 years of age were excluded. Patients were matched by age (¡À5 years), sex, admission year and ICU type. Collected data included patient demographics, admission date, ICU and hospital mortality and LOS, mechanical ventilation days, serum creatinine concentration, hemoglobin concentration, number of blood transfusions, and ICU resource use. Results: rHuEPO-treated patients (n=391) were matched with 782 controls. Patients receiving rHuEPO had higher Simplifi ed Acute Physiology Scores II (46.2 vs 38.8; p <0.001) and received signifi cantly more blood transfusions than control patients (19 vs 6; p <0.001). After adjusting for severity of illness in a linear regression model, rHuEPO was signifi cantly associated with increased blood transfusions and higher mortality risk. Patients receiving rHuEPO had signifi cantly longer hospital and ICU LOS, mechanical ventilation duration, and higher hospital and ICU mortality rate and hospital resource use (p <0.001). Conclusions: In this real-world retrospective analysis, critically ill patients treated with rHuEPO did not experience clinical benefi ts; however, patients were sicker and received rHuEPO late in their ICU stay. Monitoring prescribing patterns and patient selection of rHuEPO treatment in critically ill patients in clinical practice is recommended to optimize rHuEPO use and outcomes.


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Critical Care of the Liver Transplant ICU Patients: A Pittsburgh “Point of View”

The purpose of this review is to summarize the advances in critical care management of the liver transplant ICU patients (patients with end stage liver disease, before and after orthotopic liver transplant). The review is based on search of Medline literature, with a focus on liver failure patients and critical care issues around liver transplantation. Starzl Transplantation Institute at the University of Pittsburgh Medical Center is one of the global leaders in the treatment of end stage liver disease (ESLD). This review is in part based on our work in the 28-bed liver transplant ICU at Montefi ore Hospital, University of Pittsburgh Medical Center, in Pittsburgh, PA. Over the past few years, our understanding of the several important pathophysiologic markers of end stage liver disease has been signifi cantly improved. For example, we do now much better understand hyperdynamic circulation of liver failure, hepatorenal syndrome and its consequences, the role of TIPSS (transjugular intrahepatic portosystemic shunt) and adrenal insuffi ciency in liver failure patients. The management and prophylaxis of variceal bleeding and subacute bacterial peritonitis (SBP), has been successfully standardized. These and other advances in understanding of ESLD pathophysiology and its clinical results, have certainly contributed to more promising outcomes in the ICU management of these complex patients.


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Abdominal Sarcoidosis

Abdominal sarcoidosis is an uncommon form of sarcoidosis. The clinical presentation of esophageal, gastric, small bowel, colon, appendicular, spleen, pancreas, and abdominal aortic sarcoidosis are discussed in this review. The differential diagnosis of abdominal sarcoidosis is extensive. Other granulomatous diseases including tuberculosis, fungal infections, parasitic diseases, infl ammatory bowel disease, and Whipple’s disease should be excluded before making the diagnosis of gastrointestinal sarcoidosis. Corticosteroid therapy is the mainstay of medical therapy in abdominal sarcoidosis. Second line agents such as methotrexate are also discussed. Surgical intervention may be necessary in patients with bowel obstruction, perforation, or massive hemorrhage. The authors also provide their experience regarding preoperative pulmonary evaluation of patients with pulmonary sarcoidosis undergoing surgery.


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Acid-Base Disturbance Analysis: Comparison of the Traditional and Stewart Approaches

Introduction: The new approach to acid-base balance which initially proposed by Stewart in 1978 was success to provide a new insight which more easy to understand what is the cause, the mechanism and the degree of acid-base disturbance. The purpose of the present study was to compare two different methods of analysis acid-base disturbance in patients admitted to Pediatric Intensive Care Unit (PICU). Methods: The study was performed in 43 patients admitted to the pediatric intensive care unit of Cipto Mangunkusumo Hospital, Jakarta. Sodium, potassium, chloride, albumin, lactate and arterial blood gases were measured. All samples were taken from artery in every patient. The anion gap (AG) was calculated using the Narins method (1977), the corrected anion gap (AGcorr) using the Moviat method (2003), the strong ion gap (SIG) using Kellum method (1995) and the base excess unmeasured anions (BEUA) using the Fencl-Stewart method simplifi ed by Story (2003). Results: The presence of unmeasured ions identifi ed by signifi cantly abnormal BEUA was poorly identifi ed by SBE. Of the 43 patients included in the study, 18 (41.9%) had a different interpretation of acid-base balance when the Fencl-Stewart method was used compared to using SBE. There was good correlation between SIG and AG (r =0.831), and there was excellent correlation between SIG and AGcorr (r =0.991). Conclusions: In the condition of electrolyte unbalance and hypoalbuminemia the Stewart approach is better than the traditional approach. Nevertheless, the calculation of SIG is more timeconsuming, therefore the corrected anion gap (AGcorr) was suggested to use in clinical practice as a combination with SBE.


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Extra-Pulmonary Sarcoidosis: Neurosarcoidosis - Case Presentation and Literature Review

More than a century after the description of sarcoidosis, the disease remains not well understood. Sarcoidosis is an infl ammatory disease of unknown etiology characterized by noncaseating granulomas with multiple organs affected. The epidemiology reveals lung involvement in 90- 95% of the patients and just 5-13% incidence of neurological involvement. We present an unusual case of a patient with medulla oblongata and retroperitoneal sarcoidosis with no other organ involvement. In addition to the case presentation and extensive up-to-date literature review on extrapulmonary sarcoidosis, we describe the diffi culties in making the diagnosis and the challenge in differentiating sarcoidosis from other illnesses such as tuberculosis.


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Non Infectious Pulmonary Complications after Bone Marrow Transplant with a Special Focus on Idiopathic Pneumonia Syndrome

Pulmonary complications are a signifi cant cause of early mortality (up to 100 days) after hematopoietic stem cell transplantation (HSCT). While infectious complications particularly due to opportunistic pathogens are common in these patients, diffuse lung injury is a non-infectious complication occurring in 25-50% of HSCT recipients. The incidence of this complication is higher with allogeneic as apposed to autologous transplants and is largely dependant on the method of graft versus host prophylaxis. The spectrum includes interstitial pneumonitis (IP), bronchiolitis obliterans (BO), diffuse alveolar hemorrhage (DAH) and noncardiogenic capillary leak syndrome (NCLS). In 1993 a panel convened by the National Institutes of Health (NIH) defi ned widespread alveolar injury following HSCT that occurs in the absence of an active lower respiratory tract infection and cardiogenic causes as the idiopathic pneumonia syndrome (IPS). IPS is a clinical syndrome with variable histopathologic correlates and several potential etiologies. Peri-engraftment respiratory distress syndrome (PERDS) and delayed pulmonary toxicity syndrome (DPTS) are also included within the defi nition of IPS. Histopathologic fi ndings associated with IPS include diffuse alveolar damage with hyaline membranes, lymphocytic bronchitis and bronchiolitis obliterans organizing pneumonia (BOOP). The pathophysiology involves four distinct mechanisms, namely: the toxic effects of chemotherapy, immune dysregulation, alloreactive donor cells and host cell responses. The roles of lipopolysaccharide (LPS), monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor (TNF) in the genesis of endothelial cell injury are being defi ned. Therapy for IPS includes supportive care and immunosuppressive agents. The role of TNF antagonists is being studied in ongoing clinical trials.


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