Community- and healthcare-associated infections in critically ill patients: a multicenter cohort study.

OBJECTIVE: To compare the spectrum of infection, comorbidities, outcomes, and mortality of patients admitted to the intensive care unit (ICU) due to community-acquired or healthcare-associated severe sepsis. METHODS: This prospective cohort study was conducted in three university medical centers in Lebanon from February 2005 to December 2006. Patients with severe sepsis were included and followed up until hospital discharge or death. RESULTS: One hundred and twenty patients were included of whom 60% had community-acquired infections (CAI) and 40% had healthcare-associated infections (HAI). The most common infection in both groups was pneumonia. Hematologic malignancies were the only comorbidity more prevalent in HAI than in CAI (p=0.047). Fungal infections and extended-spectrum beta-lactamase (ESBL) organisms were more frequent in HAI than in CAI (p=0.04 and 0.029, respectively). APACHE and SOFA scores were high and did not differ between the two groups, nor did the proportion of septic shock, while mortality was significantly higher in the HAI patients than in the CAI patients (p=0.004). On multivariate analysis for mortality, independent risk factors were the source of infection acquisition (p=0.004), APACHE II score (p=0.006), multidrug-resistant Pseudomonas infections (p=0.043), and fungal infections (p=0.006). CONCLUSIONS: Severe sepsis and septic shock had a high mortality rate, especially in the HAI group. Patients with risk factors for increased mortality should be monitored and aggressive treatment should be administered.

Acute onset of psychosis in a patient with a left temporal lobe arachnoid cyst.

Arachnoid cysts are considered a rare neurological tumor, few of which exhibit any symptomatology. A 38-year-old Haitian American female with no past psychiatric history presented with rapid onset of psychosis. Workup for medical etiology proved to be within normal limits, with the exception of a left temporal lobe arachnoid cyst. The purpose of this paper is to add to a number of existing case reports that suggest a relationship between such lesions and psychiatric illness.

Effect of heliox- and air-driven nebulized bronchodilator therapy on lung function in patients with asthma.

BACKGROUND: This study compares the effect of heliox-driven to that of air-driven bronchodilator therapy on the pulmonary function test (PFT) in patients with different levels of asthma severity. METHODS: One-hundred thirty-two participants were included in the study. Participants underwent spirometry twice with bronchodilator testing on two consecutive days. Air-driven nebulization was used one day and heliox-driven nebulization the other day in random order crossover design. After a baseline PFT, each participant received 2.5 mg of albuterol sulfate nebulized with the randomized driving gas. Post bronchodilator PFT was repeated after 30 min. The next day, the exact same protocol was repeated, except that the other driving gas was used to nebulize the drug. Participants were subgrouped and analyzed according to their baseline FEV(1) on day 1: Group I, FEV(1) ≥80 %; Group II, 80 % > FEV(1) > 50 %; Group III, FEV(1) ≤50 %. The proportion of participants with greater than 12 % and 200-mL increases from their baseline FEV(1) and the changes from baseline in PFT variables were compared between heliox-driven versus air-driven bronchodilation therapy. RESULTS: The proportion of participants with >12 % and 200-mL increases from their baseline FEV(1) with air- or heliox-driven bronchodilation was not different with respect to the proportion of participants with baseline FEV(1) ≥80 % (20 vs. 18 %, respectively) and 80 % > FEV(1) > 50 % (36 vs. 43 %, respectively), but it was significantly greater with heliox-driven bronchodilation in participants with FEV(1) ≤50 % (43 vs. 73 %, respectively; p = 0.01). Changes from baseline FVC, FEV(1), FEV(1)/FVC, FEF(25-75) %, FEF(max), FEF(25) %, FEF(50) %, and FEF(75) % were significantly larger with heliox-driven versus air-driven bronchodilation in participants with baseline FEV(1) ≤50 %. CONCLUSION: Improvements in PFT variables are more frequent and profound with heliox-driven compared to air-driven bronchodilator therapy only in asthmatic patients with baseline FEV(1) ≤50 %.

Characterization of altered patterns of endothelial progenitor cells in sickle cell disease related pulmonary arterial hypertension.

Endothelial dysfunction plays an important role in the pathogenesis of pulmonary arterial hypertension (PAH) in sickle cell disease (SCD). A variety of evidence suggests that circulating endothelial progenitor cells (EPCs) play an integral role in vascular repair. We hypothesized that SCD patients with PAH are deficient in EPCs, potentially contributing to endothelial dysfunction and disease progression. The number of circulating CD34+/CD14-/CD106+ EPCs was significantly lower in SCD patients with PAH than without PAH (P=0.025). CD34+/CD14-/CD106+ numbers significantly correlated with tricuspid regurgitation velocity (TRV, r=-0.44, P=0.033) 6-minute walk distance (6MWD, r= 0.72, P=0.001), mean pulmonary artery pressure (mPAP, r= -0.43, P=0.05), and pulmonary vascular resistance (PVR, r=-0.45, P=0.05). Other EPC subsets including CD31+/CD133+/CD146+ were similar between both groups. Numbers of EPCs did not correlate with age, sex, hemoglobin, WBC count, reticulocyte count, lactate dehydrogenase (LDH), iron/ferritin levels, and serum creatinine. These data indicate that subsets of EPC are lower in SCD patients with PAH than in those without PAH. Fewer EPCs in PAH patients may contribute to the pulmonary vascular pathology. Reduced number of EPCs in SCD patients with PAH might not only give potential insight into the pathophysiological mechanisms but also might be useful for identifying suitable therapeutic targets in these patients.

Uric Acid as a potential biomarker of pulmonary arterial hypertension in patients with sickle cell disease.

Serum uric acid (UA) is emerging as a strong and independent marker for pulmonary arterial hypertension (PAH). PAH is well recognized as a life threatening complication of sickle cell disease (SCD). However, the association between UA and PAH in SCD is unknown. We reviewed electronic medical records (EMR) of 559 consecutive adult SCD patients from Kings County Hospital Center (KCHC) between January 2005 and February 2010. Patients (n = 96) with measurement of UA in close temporal proximity to the transthoracic echocardiography (TTE) were identified. PAH was defined as pulmonary artery systolic pressure (PASP) ≥30 mm Hg. Patients (n = 16) with other risk factors which may cause PAH and chronic renal insufficiency were excluded. In 18 patients, TTE could not measure PASP. Finally, 62 patients were selected. Statistical analysis was performed using Student t tests, Pearson correlation coefficient and multivariate regression analysis. Out of 62 patients, 30 had PAH. Patients with PAH had a higher UA level (8.67 ± 4.8 vs. 5.35 ± 2.1, P = 0.001). We found strong positive correlation between the UA level and PASP (r = 0.71; P < 0.0001). This correlation was independent of diuretic use. UA could be a potential marker for PAH in SCD. However, its' prognostic and pathophysiologic role in SCD patients with PAH needs to be further investigated.

Fatal bilateral pneumothoraces complicating dyskeratosis congenita: a case report.

INTRODUCTION: Dyskeratosis congenita is a rare genodermatosis, characterized by a triad of reticular skin pigmentation, nail dystrophy and leukoplakia of mucous membranes. It is also associated with a variety of non-cutaneous abnormalities such as bone marrow failure, malignancy and pulmonary complications. Among its wide range of clinical manifestations, fatal pneumothorax has rarely been reported. CASE PRESENTATION: We report the case of a 31-year-old Lebanese woman with dyskeratosis congenita who succumbed to devastating bilateral pneumothoraces. CONCLUSION: Careful surveillance of patients with dyskeratosis congenita is required as incipient respiratory failure due to pneumothorax may be successfully treated if detected at an early stage.

Metabolic and respiratory variables during pressure support versus synchronized intermittent mandatory ventilation.

BACKGROUND: Mechanically ventilated patients interact and respond differently to different modes of ventilatory support. OBJECTIVES: To assess changes in metabolic and respiratory variables during equivalent changes with either pressure support ventilation (PSV) or volume-cycled synchronized intermittent mandatory ventilation (SIMV) in non-tracheostomized patients without known obstructive pulmonary disease receiving short-term mechanical ventilation in the intensive care unit. METHODS: Fourteen patients receiving volume-cycled SIMV at 12 breaths/min (SIMV(100%)) were included in the study. The PSV level (PSV(100%)) resulting in a minute volume and respiratory rate equivalent to that during SIMV(100%) was determined for each patient. Then each patient underwent trials at 66% and 33% of initial ventilator support with volume-cycled SIMV (SIMV(66%) and SIMV(33%)) and PSV (PSV(66%) and PSV(33%)) in random order. At the end of each trial, oxygen consumption ((.)VO2), carbon dioxide production ((.)VCO2), measured energy expenditures (MEE), peak inspiratory flow, total respiratory frequency, tidal volume, minute ventilation, occlusion pressure (P(0.1)) and inspiratory duty cycle (T(i)/T(tot)) were measured. RESULTS: There were smaller changes in (.)VO2, (.)VCO2 and MEE when equivalent changes were applied with PSV (15.7 +/- 4.4; 12.5 +/- 2.2 and 15 +/- 3.5%) compared with volume-cycled SIMV (32.7 +/- 7.7; 23 +/- 5.2 and 30.7 +/- 6.8%; p < 0.05). P(0.1) and T(i)/T(tot) were significantly smaller during PSV (2.64 +/- 0.28 and 0.38 +/- 0.03 cm H(2)O) than volume-cycled SIMV (4.01 +/- 0.21 and 0.43 +/- 0.02 cm H2O; p < 0.05). CONCLUSIONS: Changes in the level of PSV resulted in smaller changes in metabolic and respiratory variables compared with equivalent changes in the level of volume-cycled SIMV support. PSV may be more suitable for progressive respiratory muscle reloading.

Metastases in malignant pleural mesothelioma: a new radiological appearance.

This report describes a patient with malignant pleural mesothelioma who presented with a right-sided pleural effusion and contralateral parenchymal metastases manifesting as alveolar opacities with air bronchograms. This radiological pattern of metastases has never been described before. The patient died from respiratory failure related to extensive parenchymal metastases, an outcome seldom reported with malignant pleural mesothelioma.

Effect of pressure support ventilation and positive end expiratory pressure on the rapid shallow breathing index in intensive care unit patients.

OBJECTIVE: We compared rapid shallow breathing index (RSBI) values under various ventilatory support settings prior to extubation. DESIGN AND SETTING: Prospective study in the intensive care unit at a university hospital. PATIENTS: Thirty six patients ready for extubation. INTERVENTIONS: Patients were enrolled when receiving pressure support ventilation (PSV) of 5 cmH2O, PEEP of 5 cmH2O, and FIO2 of 40% (PS). Subsequently each patient received a trial of PSV of 0 cmH2O, PEEP of 5 cmH2O, and FIO2 of 40% (CPAP), a trial of PSV of 0 cmH2O, PEEP of 5 cmH2O and FIO2 of 21% (CPAP-R/A), and a 1-minute spontaneously breathing room air trial off the ventilator (T-piece). Trials were carried out in random order. MEASUREMENTS AND RESULTS: Respiratory frequency (f) and tidal volume (VT) were measured during PS, CPAP, CPAP-R/A, and T-piece in all patients. RSBI (f/VT) was determined for each patient under all experimental conditions, and the average RSBI was compared during PS, CPAP, CPAP-R/A, and T-piece. RSBI was significantly smaller during PS (46+/-8 bpm/l), CPAP (63+/-13 bpm/l) and CPAP-R/A (67+/-14 bpm/l) vs. T-piece (100+/-23 bpm/l). There was no significant difference in RSBI between CPAP and CPAP-R/A. RSBI during CPAP and CPAP-R/A were significantly smaller than RSBI during T-piece. In all patients RSBI values were less than 105 bpm/l during PS, CPAP, and CPAP-R/A. However, during T-piece the RSBI increased to greater than 105bpm/l in 13 of 36 patients. CONCLUSIONS: In the same patient the use of PSV and/or PEEP as low as 5 cmH2O can influence the RSBI. In contrast, changes in FIO2 may have no effect on the RSBI.

Value of pretransplant pulmonary function tests in predicting pulmonary complications after autologous peripheral stem cell transplantation.

The aim of this study was to evaluate the value of pulmonary function tests performed before an autologous peripheral stem cell transplant (APSCT) in identifying patients who are at risk for developing post-transplant pulmonary complications. This retrospective study included patients who underwent autologous peripheral stem cell transplantation from January 1997 to December 2006. The total sample consisted of 43 patients with 24 patients (55.8%) having multiple myeloma, 9 patients (20.9%) having Hodgkin's lymphoma, and 10 patients (23.3%) having non-Hodgkin's lymphoma. The patients' average age at the time of diagnosis and at the time of APSCT was 41.8 +/- 14.6 and 43.1 +/- 14.2 years, respectively. After APSCT, 8 patients (18.6%) had pulmonary complications all of which were infectious pneumonia. The mean pretransplant forced midexpiratory flow (FEF(25-75%)) in the patients who developed post-transplant pulmonary complications was significantly lower than the mean pretransplant FEF(25-75%) in the patients who did not develop post-transplant pulmonary complications (75.5 +/- 19.9% vs. 104.3 +/- 24.5%, p = 0.004). There were no other differences in the pretransplant pulmonary function test parameters between the patients who developed post-transplant pulmonary complications and the patients who did not develop post-transplant pulmonary complications. Our results showed that patients with decreased pretransplant FEF(25-75%) are at risk for developing pulmonary complications in the post autologous stem cell transplantation period.

Use of heparinized versus non-heparinized syringes for measurements of the pleural fluid pH.

BACKGROUND: Pleural fluid (PF) pH measurement is important for establishing a diagnosis and for guiding clinical management. The current standard practice is to collect PF samples for pH measurement in heparinized syringes at room temperature and to instantaneously process these samples. OBJECTIVE: The purpose of this study is to investigate the effect of collecting PF in heparinized versus non-heparinized syringes at room temperature on PF pH measurements when processed at various time intervals. METHODS: From 50 consecutive thoracenteses, 1 ml of PF was collected anaerobically in each of six 3-ml syringes. Only three syringes were coated with heparin. The samples were processed for PF pH measurements at time 0 (T(0)) and 1 h (T(1)) and 2 h (T(2)) after collection. All specimens were preserved at room temperature, until the measurements were carried out in duplicates by a calibrated blood gas analyzer. RESULTS: PF pH values were significantly lower with heparinized versus non-heparinized syringes at all time intervals (T(0): pH heparinized = 7.378 +/- 0.107 vs. pH non-heparinized = 7.390 +/- 0.108; T(1): pH heparinized = 7.378 +/- 0.115 vs. pH non-heparinized = 7.389 +/- 0.111; T(2): pH heparinized = 7.367 +/- 0.105 vs. pH non-heparinized = 7.389 +/- 0.121). In the heparinized syringes, there was a significant decrease in PF pH values at T(2) versus T(0) and T(1). There were no significant changes in PF pH values over time in the non-heparinized syringes. CONCLUSIONS: For serial PF pH measurements, the same type of syringes (either heparinized or non-heparinized) should be consistently used. With heparinized syringes, processing of PF pH measurements should be performed within 1 h after collection.

Endobronchial stenting for respiratory complications in relapsing polychondritis.

Relapsing polychondritis is characterized by recurrent inflammation and destruction of the cartilage and connective tissue. Respiratory complications are frequently severe during the course of the disease and usually signal a poor prognosis. We report a case of a 47-year-old man with known relapsing polychondritis who presented with bilateral narrowing of the airways complicated by refractory cavitary Pseudomonas aeruginosa pneumonia. Despite an aggressive antibiotic regimen, the patient's pneumonia did not improve until bronchial stenting 4 months later.

Extranodal marginal zone lymphoma of MALT involving the lungs, the stomach, and the colon.

Extranodal marginal zone lymphoma of MALT, previously known as MALT lymphoma, is a low grade B-cell Non-Hodgkin's lymphoma (NHL). Its most frequent locations are the gastrointestinal tract and the lungs while that of the colon is rare. Involvement of multiple mucosal sites is not a frequent finding but it does occur. We describe a case of a 70-year-old man who presented with extranodal marginal zone lymphoma of MALT involving three different sites: the lungs, the stomach, and the colon.

Thiazolidinediones associated with recurrent pleural effusions post coronary artery bypass surgery.

We report the case of a patient in which thiazolidinediones (TZDs) were associated with recurrent pleural effusions post coronary artery bypass surgery, in spite of a normal left ventricular function. The potential mechanisms are discussed, particularly in relation to the "vascular leak syndrome". This finding has important implications for the management of diabetic patients who are referred for coronary artery bypass surgery and who are on TZDs for glycemic control.

Detection of a highly prevalent and potentially virulent strain of Pseudomonas aeruginosa from nosocomial infections in a medical center.

BACKGROUND: We correlated genotypes, virulence factors and antimicrobial susceptibility patterns of nosocomially identified Pseudomonas aeruginosa isolates from clinical specimens to those of environmental isolates encountered in the same units of a medical center. Antibiotic susceptibility testing, RAPD analysis and detection of enzymatic activities of extracellular virulence factors, were done on these isolates. RESULTS: Data showed that most of the clinical and environmental isolates were susceptible to tested antimicrobial agents. RAPD analysis determined the presence of 31 genotypes, with genotype 1 detected in 42% of the clinical isolates and 43% of the environmental isolates. Enzymatic activity testing showed that genotype 1 produced all virulence factors tested for. CONCLUSION: In conclusion, our data demonstrated the predominant prevalence of a potentially virulent P. aeruginosa genotype, circulating in a number of units of the medical center and emphasize the need to reinforce infection control measures.

A new oxygenation index for reflecting intrapulmonary shunting in patients undergoing open-heart surgery.

STUDY OBJECTIVES: To assess the reliability of new and traditional oxygenation measurements in reflecting intrapulmonary shunt. DESIGN: Prospective study. SETTING: Cardiac surgery unit at a university hospital. PATIENTS: Fifty-five patients undergoing coronary artery bypass grafting. MEASUREMENTS AND RESULTS: Simultaneous blood samples were collected from an indwelling arterial line and a catheter for determination of blood gases. Standard accepted formulas were utilized to measure a new oxygenation index: PaO(2)/fraction of inspired oxygen (FIO(2)) x mean airway pressure (Paw). The standard formulas used were the oxygenation ratio (PaO(2)/FIO(2)), PaO(2)/alveolar partial oxygen pressure (PAO(2)), alveolar-arterial oxygen tension gradient (P[A-a]O(2)), and intrapulmonary shunt (venous admixture [Qsp/Qt]). There were significant negative (p < 0.05) correlations between the PaO(2)/(FIO(2) x Paw) and Qsp/Qt (r = - 0.85), between the PaO(2)/FIO(2) and Qsp/Qt (r = - 0.74), and between the PaO(2)/PAO(2) and Qsp/Qt (r = - 0.71). There was a significant positive (p < 0.05) correlation between the P(A-a)O(2) gradient and Qsp/Qt (r = 0.66). However, the correlation was strongest between the PaO(2)/(FIO(2) x Paw) and Qsp/Qt. CONCLUSION: In this group of patients, PaO(2)/(FIO(2) x Paw) might be more reliable than other oxygenation measurements in reflecting intrapulmonary shunt.

Buspirone treatment for apneustic breathing in brain stem infarct.

We report a case of brainstem infarction resulting in apneustic breathing, which was alleviated with buspirone. We discuss apneusis, review the literature, and speculate about the benefit of serotonin 1A receptor agonists in the treatment of apneusis and other respiratory disorders.

Leukotriene antagonists and the Churg-Strauss syndrome.

BACKGROUND AND OBJECTIVES: Leukotriene antagonists (LTAs), or antileukotrienes, are a new group of anti-inflammatory drugs used for the treatment of asthma. They might substitute for or allow tapering of corticosteroids in asthmatic patients. These drugs have been associated with the development of Churg-Strauss syndrome (CSS), a rare form of vasculitic angiitis. It is unclear whether the development of CSS is a direct drug effect or an unmasking of a preexisting condition on withdrawal of steroids for asthma. We present a case of CSS in a patient treated with montelukast and review the literature to analyze the association between LTAs and the development of CSS. METHOD: We reviewed the literature using MEDLINE from February 1966 to October 2000. To the cases identified, we present an additional case of a patient who underwent a diagnostic lung biopsy. RESULTS: Twenty-two case reports of patients receiving LTAs who developed CSS were identified. The onset of CSS occurred 2 days to 10 months after starting treatment with LTAs. All patients had received inhaled or oral steroids for asthma. The interval between the last oral corticosteroid treatment and CSS onset ranged from 3 days to 8 months. CONCLUSIONS: To date, there is no compelling evidence that the development of CSS in asthmatic patients receiving LTAs results from a direct drug effect. Rather, it appears that tapering of corticosteroids in these patients unmasks the multiorgan manifestations of the disease. We believe that the use of LTAs should not be influenced by the apparent increase in the incidence of CSS and that these are still safe drugs for asthma.