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.

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.

Epidemiologic, clinical characteristics, and risk factors for adverse outcome in multiresistant gram-negative primary bacteremia of critically ill patients.

BACKGROUND: Characteristics and burden of primary bacteremia because of multidrug-resistant (MDR) gram-negative bacteria (GNB) in intensive care unit (ICU) patients remain understudied. METHODS: A cohort study of patients with primary MDR GNB-related bacteremia from the ICU of a tertiary Greek hospital during a 3-year period was conducted for recognition of clinical characteristics and risk factors for adverse outcome. A case-control study was further performed to evaluate risk factors for development of MDR GNB-related primary bacteremia. RESULTS: Fifty monomicrobial episodes of primary bacteremia because of Klebsiella pneumoniae (n = 20), Acinetobacter baumannii (n = 18), and Pseudomonas aeruginosa (n = 12) were recorded. The presence of diabetes mellitus was the only significant risk factor for development of MDR GNB-related primary bacteremia. Most episodes (78%) were ICU acquired in patients with prolonged mechanical ventilation and previous hospitalization in the ward. Mortality was 47.6% vs 19% of controls, P = .01. Mortality was higher in recurrent bacteremia (62.5%). Mortality was statistically associated with age (P = .002) and degree of multiorgan dysfunction expressed by sequential organ failure assessment score on day of bacteremia documentation (P = .001). CONCLUSION: Critically ill patients with MDR GNB-related primary bacteremia present significant mortality mainly associated with age and multiorgan failure. A baumanii bacteremia confers significant mortality compared with the benign course of K pneumoniae in such settings. Diabetes mellitus is a risk factor for development of such episodes, which may, in part, be general ward acquired, underlining the need for expanded vigilance.

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 C(max):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.

Near-drowning: clinical course of lung injury in adults.

BACKGROUND AND OBJECTIVES: Although anoxic encephalopathy is the most dreaded consequence of submersion accidents, respiratory involvement is also very common in these patients. Nevertheless, few data are available about the clinical course and resolution of lung injury in adult victims of near-drowning. Our goal was to study the clinical manifestations of near-drowning and the course of respiratory involvement in a retrospective cohort of adult, mostly elderly patients. PATIENTS: Our study included adult patients who were hospitalized after near-drowning in seawater over an 8-year period. Forty-three patients (26 female, 17 male), with an age range of 18-88 years old, were studied. Most (79%) of the patients were elderly (>60 years). RESULTS: In the Emergency Department two patients were comatose and required intubation. Another patient was intubated within the first 24 h because of ARDS. At presentation, all patients but two had a PaO(2)/FiO(2) < 300, while ARDS was present in 17 and acute lung injury in 15 cases. The nine remaining hypoxemic patients had either focal infiltrates or a negative chest X-ray. Superimposed pneumonia was observed in four patients and resulted in a protracted hospital stay. Improvement of lung injury was rapid in most cases: by day 4 resolution of hypoxemia was observed in 33/43 (76.7%) of the cases and resolution of radiographic findings in 66.6%. Duration of hospitalization varied from 2 to 14 days (mean = 5.2 +/- 0.5 days). One patient with coma died due to ventilator-associated pneumonia (mortality = 2.3%). CONCLUSION: Respiratory manifestations of near-drowning in adult immersion victims are often severe. Nevertheless, in noncomatose patients at least, intubation can often be avoided and quick improvement is the rule while a good outcome is usually expected even in elderly patients.

Coronary artery disease and upper abdominal surgery: impact of anesthesia on perioperative myocardial ischemia.

BACKGROUND/AIMS: Some papers claim that epidural anesthesia and analgesia lowers the incidence of perioperative ischemic events and may have a favorable effect on perioperative cardiac morbidity and mortality. We studied the effect of epidural anesthesia and analgesia on perioperative myocardial ischemia, in a group of patients with known coronary artery disease, who underwent upper abdominal surgery. METHODOLOGY: Fifty patients with coronary artery disease scheduled for elective upper abdominal surgery, were randomized to two study groups: Group A (n = 25) received general anesthesia plus epidural anesthesia and analgesia, while group B (n = 25) received general anesthesia with postoperative i.v. analgesia. All patients had Holter ECG recording from 24 hours preoperatively until 48 hours postoperatively. RESULTS: Preoperatively, no significant differences in ischemic burden were observed between the two groups. Intraoperatively, significantly fewer patients in group A had ischemic episodes (8% vs. 36%, p < 0.05) and there was also a significant reduction in the number of ischemic episodes and in mean duration of ischemia per hour of monitoring. Similar findings were observed in the first 24 hours postoperatively but not later on, with 12% of patients in group A having ischemic episodes vs. 60% in group B (p < 0.01). Group A had significantly better pain control postoperatively. Only one third of ischemic episodes were related to hemodynamic abnormality, and most of them were clinically silent. No serious cardiac morbidity or mortality was observed during the period of monitoring. CONCLUSIONS: Epidural anesthesia and analgesia reduces intraoperative and early postoperative ischemia in patients with known coronary artery disease undergoing upper abdominal surgery.

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.

Severity of illness and outcome in adult patients with primary varicella pneumonia.

BACKGROUND: Varicella pneumonia is a serious complication of primary varicella infection in adults that often results in respiratory failure and death. OBJECTIVE: To analyze the clinical and laboratory manifestations of primary varicella pneumonia in patients admitted to our intensive care unit (ICU). METHODS: Retrospective study on patients treated in our ICU with a diagnosis of primary varicella pneumonia during a period of 15 years. We recorded age, gender, smoking habits, clinical and laboratory findings, arterial blood gases, chest radiograph, illness severity (SAPS II), length of stay, necessity for mechanical ventilation, complications, therapy and survival. We examined the influence of the duration of respiratory symptoms and rash prior to admission, and the influence of illness severity on outcome. RESULTS: There was a statistically significant difference in duration of respiratory symptoms, duration of rash and SAPS II on admission between: (a) mechanically ventilated patients vs. spontaneously breathing patients (p < 0.007, p < 0.00, p < 0.00), (b) patients who survived vs. patients with poor outcome (p < 0.001, p < 0.000, p < 0.000), and (c) mechanically ventilated patients with poor outcome vs. mechanically ventilated patients who survived (p < 0.001, p < 0.00, p < 0.000). Overall mortality was 13.6%; death occurred only in mechanically ventilated patients (mortality 33.3%). CONCLUSIONS: Primary varicella pneumonia remains a critical problem with significant mortality. When recognized before respiratory failure ensues and mechanical ventilation becomes mandatory, patients could have an excellent outcome. Adult patients who delay asking for medical support, the disease may lead to the need for mechanical ventilation and severe complications with a fatal outcome.