Intravenous colistin in the treatment of sepsis from multiresistant Gram-negative bacilli in critically ill patients

INTRODUCTION: The increasing prevalence of multiresistant Gram-negative strains in intensive care units (ICUs) has recently rekindled interest in colistin, a bactericidal antibiotic that was used in the 1960s for treatment of infections caused by Gram-negative bacilli. We conducted the present observational study to evaluate the efficacy of intravenous colistin in the treatment of critically ill patients with sepsis caused by Gram-negative bacilli resistant to all other antibiotics. PATIENTS AND METHOD: Critically ill patients with sepsis caused by Gram-negative bacilli resistant to all antibiotics with the exception of colistin were treated in the six-bed ICU of a trauma hospital. Diagnosis of infection was based on clinical data and isolation of bacteria, and the bacteria were tested with respect to their susceptibility to colistin. Clinical response to colistin was evaluated. RESULTS: Twenty-four patients (mean age 44.3 years, mean Acute Physiology and Chronic Health Evaluation II score 20.6) received 26 courses of colistin. Clinical response was observed for 73% of the treatments. Survival at 30 days was 57.7%. Deterioration in renal function was observed in 14.3% of 21 patients who were not already receiving renal replacement therapy, but in only one case did this deterioration have serious clinical consequences. CONCLUSION: The lack of a control group in the present study does not allow any definite conclusions to be drawn regarding the clinical effectiveness of colistin. On the other hand, this drug has an acceptable safety profile and its use should be considered in severe infections with multiresistant Gram-negative bacilli

Cerebral fat embolism and the "starfield" pattern: a case report

Nearly all long-bone fractures are accompanied by some form of fat embolism. The rare complication of clinically significant fat embolism syndrome, however, occurs in only 0.9-2.2% of cases. The clinical triad of fat embolism syndrome consists of respiratory distress, altered mental status, and petechial rash. Cerebral fat embolism causes the neurologic involvement seen in fat embolism syndrome. A 19-year-old African-American male was admitted with gunshot wounds to his right hand and right knee. He had diffuse hyperactive deep tendon reflexes, bilateral ankle clonus and decerebrate posturing with a Glasgow Coma Scale (GCS) score of 4T. Subsequent MRI of the brain showed innumerable punctate areas of restricted diffusion consistent with "starfield" pattern. On a 10-week follow up he has a normal neurological examination and he is discharged home. Despite the severity of the neurologic insult upon initial presentation, the majority of case reports on cerebral fat embolism illustrate that cerebral dysfunction associated with cerebral fat embolism is reversible. When neurologic deterioration occurs in the non-head trauma patient, then a systemic cause such as fat emboli should be considered. We describe a patient with non-head trauma who demonstrated the classic "starfield" pattern on diffusion-weighted MRI imaging

Recovery from severe inhalational phosphine poisoning. Report of two cases

Phosphine is a highly toxic fumigant used as a general pesticide in places of grain storage. The duration of exposure, as well as the concentration of the inhaled gas largely determines clinical findings. We present two cases of severe inhalational phosphine poisoning and their management in the Intensive Care Unit. Clinical, laboratory and radiological findings are described, as well as therapeutic and preventive measures

Increased blood troponin levels in ICU patients

PURPOSE OF REVIEW: Cardiac troponins in serum have become the biomarkers of choice for the diagnosis of myocardial infarction. Yet, troponin can also be elevated by a multitude of causes in the absence of overt myocardial ischemia. Such nonspecific elevations are particularly common in the critically ill. This article aims to provide information on the significance of troponin elevations in unselected critically ill patients and in patients with sepsis or septic shock. RECENT FINDINGS: Recent studies reconsider the possible association of troponin elevations with myocardial infarction in unselected critically ill patients. There are also more data on the prognostic significance of troponin in this population. In patients with sepsis, recent studies suggest that troponin may be a reliable index of sepsis-induced myocardial dysfunction, although the implications of this finding in the management of sepsis remain unclear for the time being. Troponin also appears to be a predictor of short and possibly also long-term outcome in septic patients. The advent of newer assays with even higher sensitivity, may lead to further redefinition of the role of troponin in the ICU. SUMMARY: Troponin is frequently elevated in critically ill patients. More research is needed on the diagnostic and prognostic significance and possible clinical applications of troponin measurements in patients with sepsis and critical illness. © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins

Rare roentgenologic manifestations of pulmonary edema

PURPOSE OF REVIEW: Unilateral pulmonary edema (UPE) is an unusual manifestation of pulmonary edema that is frequently confused with other causes of unilateral alveolar and interstitial infiltrates. Until now limited data existed regarding the prevalence, cause, and outcome of patients presenting with cardiogenic UPE. The purpose of this review is to give insights into this rare entity. RECENT FINDINGS: In a recent retrospective study, the prevalence of UPE was 2.1% of all cases of cardiogenic pulmonary edema. UPE was right-sided in 89%. All patients with UPE had severe mitral regurgitation. In patients with UPE, blood pressure was significantly lower, whereas noninvasive or invasive ventilation and catecholamines were used more frequently compared with patients with bilateral pulmonary edema. In-hospital mortality was higher for patients with UPE (39 vs. 8% for bilateral pulmonary edema) and UPE was independently related to death (a 6.5-fold higher risk of death). Delayed treatment of UPE could be one of the explanations for this increased mortality. SUMMARY: UPE is not that rare as considered to be and is mostly related to severe organic or functional mitral regurgitation. Probably because of initial misdiagnosis and delayed appropriate treatment, UPE is related to increased mortality. History, absence of signs of infection, and elevated serum cardiac markers such as B-natriuretic peptide may help to differentiate UPE from other diagnoses. The key examination remains bedside transthoracic echocardiography, although transesophageal echocardiography can also provide additional information regarding the severity and mechanism of mitral regurgitation and documentation of the differential pressure between the right and left pulmonary veins. © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins

Pharmacokinetic evaluation of colistin sodium

Importance of the field: Although colistin has recently played a key role in the treatment of nosocomial infections due to multidrug resistant Gram-negative pathogens, there is a lack of clinical studies examining colistin pharmacokinetics (PKs) in humans. This refers to all routes of colistin administration in clinical practice. Colistin PK data are also limited in critically ill patients. Areas covered in this review: Literature search took into account data dealing with colistin PK obtained from animal studies performed during previous decades (1970s, 1980s and 1990s) and from recent human studies performed during the last decade. What the reader will gain: Valuable information on pharmacodynamics (PD)/PK of colistin used in the treatments of nosocomial infections due to multidrug resistant Gram-negative pathogens, mostly Pseudomonas aeruginosa, Acinetobacter baumannii and Klebsiella pneumoniae. A better understanding of PKs could offer significant improvement of colistin use in humans, especially optimization of colistin doses in different routes of administration in order to maximize clinical efficacy and minimize adverse effects and rate of resistance. Take home message: There is a lack of human studies on colistin PK and PD. Significant PD parameters best predicting colistin efficacy and their optimal values such as Cmax:MIC ratio, AUC/MIC and T > MIC have not yet been clearly defined. It should be noted that further investigation on colistin PK/PD in vitro and in vivo models is required. © 2011 Informa UK, Ltd