Antimicrobial-coated endotracheal tubes: an experimental study

OBJECTIVE: Antibiotic-resistant bacterial biofilm may quickly form on endotracheal tubes (ETTs) and can enter the lungs, potentially causing pneumonia. In an attempt to prevent bacterial colonization, we developed and tested in an in-vitro study and animal study several antibacterial-coated ETTs (silver sulfadiazine with and without carbon in polyurethane, silver sulfadiazine and chlorhexidine with and without carbon in polyurethane, silver-platinum with and without carbon in polyurethane, chlorhexidine in polyurethane, and rose bengal for UV light). DESIGN, SETTING, ANIMALS, INTERVENTIONS: After preliminary studies, silver sulfadiazine in polyurethane (SSD-ETT) was selected among the coatings to be challenged every 24 h with 10(4)-10(6) Pseudomonas aeruginosa/ml and evaluated at 6 h, 24 h, and 72 h with standard microbiological studies, scanning electron microscopy, and confocal scanning microscopy. Subsequently, eight sheep were randomized to receive either a SSD-ETT or a standard ETT (St-ETT). After 24 h of mechanical ventilation, standard microbiological studies were performed together with scanning electron microscopy and confocal microscopy. MEASUREMENTS AND RESULTS: In the in-vitro study SSD-ETT remained bacteria-free for up to 72 h, whereas St-ETT showed heavy P. aeruginosa growth and biofilm formation (p < 0.01). In sheep, the SSD-ETT group showed no bacterial growth in the ETT, ventilator tubing, and lower respiratory tract, while heavy colonization was found in the St-ETT (p < 0.01), ventilator tubing (p=0.03), and lower respiratory tract (p < 0.01). CONCLUSION: This study describes several effective and durable antibacterial coatings for ETTs. Particularly, SSD-ETT showed prevention against P. aeruginosa biofilm formation in a 72-h in-vitro study and lower respiratory tract colonization in sheep mechanically ventilated for 24 h.     

Antibacterial-coated tracheal tubes cleaned with the Mucus Shaver

OBJECTIVE: To assess the long-term benefit from antibacterial coatings of the tracheal tube (ETT), and to keep clean the lumen of the ETT. DESIGN: Experimental animal study. SETTING: USA National Institutes of Health. SUBJECTS: Twelve sheep. INTERVENTIONS: Twelve ETTs were internally dip-coated with a silver-sulfadiazine in polyurethane. We developed a concentric inflatable silicone rubber "razor", the Mucus Shaver (MS), to shave the ETT lumen free of mucus. In a single pass, we cleaned all mucus from the internal surface of the ETT. Control group: Five intubated sheep were mechanically ventilated for 72 h. The ETT was suctioned every 6 h. Study group: Six sheep were intubated and mechanically ventilated for 72 h. The ETT was suctioned and cleaned with the MS every 6 h. An additional sheep was intubated and mechanically ventilated for 168 h. Bacteriologic studies and scanning electron microscopy were performed to assess bacterial colonization and thickness of secretions on the internal surface of the ETT. MEASUREMENTS AND MAIN RESULTS: In the control group, the ETT was always heavily colonized: median debris thickness was 380 microm, range 270-550 microm. In the study group, there was no colonization and no secretions in the ETT, except for three ETT that were colonized solely at the very tip. CONCLUSIONS: Silver-based coating of ETT cleaned with the MS every 6 h significantly reduces accumulation of mucus/secretion and bacterial growth within the ETT following 72 h of mechanical ventilation.     

A polyurethane cuffed endotracheal tube is associated with decreased rates of ventilator-associated pneumonia

Purpose

The aim of this study was to determine whether the use of a polyurethane-cuffed endotracheal tube would result in a decrease in ventilator-associated pneumonia rate.

Materials and Methods

We replaced conventional endotracheal tube with a polyurethane-cuff endotracheal tube (Microcuff, Kimberly-Clark Corporation, Rosewell, Ga) in all adult mechanically ventilated patients throughout our large academic hospital from July 2007 to June 2008. We retrospectively compared the rates of ventilator-associated pneumonia before, during, and after the intervention year by interrupted time-series analysis.

Results

Ventilator-associated pneumonia rates decreased from 5.3 per 1000 ventilator days before the use of the polyurethane-cuffed endotracheal tube to 2.8 per 1000 ventilator days during the intervention year (P = .0138). During the first 3 months after return to conventional tubes, the rate of ventilator-associated pneumonia was 3.5/1000 ventilator days. Use of the polyurethane-cuffed endotracheal tube was associated with an incidence risk ratio of ventilator-associated pneumonia of 0.572 (95% confidence interval, 0.340-0.963). In statistical regression analysis controlling for other possible alterations in the hospital environment, as measured by rate of tracheostomy-ventilator-associated pneumonia, the incidence risk ratio of ventilator-associated pneumonia in patients intubated with polyurethane-cuffed endotracheal tube was 0.565 (P = .032; 95% confidence interval, 0.335-0.953).

Conclusions

Use of a polyurethane-cuffed endotracheal tube was associated with a significant decrease in the rate of ventilator-associated pneumonia in our study.     

An open-labelled randomized controlled trial comparing costs and clinical outcomes of open endotracheal suctioning with closed endotracheal suctioning in mechanically ventilated medical intensive care patients

Purpose

Closed endotracheal suctioning (CES) may impact ventilator-associated pneumonia (VAP) risk by reducing environmental contamination. In developing countries where resource limitations constrain the provision of optimal bed space for critically ill patients, CES assumes greater importance.

Materials and Methods

In this prospective, open-labeled, randomized controlled trial spanning 10 months, we compared CES with open endotracheal suctioning (OES) in mechanically ventilated patients admitted to the medical intensive care unit (ICU) of a university-affiliated teaching hospital. Patients were followed up from ICU admission to death or discharge from hospital. Primary outcome was incidence of VAP. Secondary outcomes included mortality, cost, and length of stay.

Results

Two hundred patients were recruited, 100 in each arm. The incidence of VAP was 23.5%. Closed endotracheal suctioning was associated with a trend to a reduced incidence of VAP (odds ratio, 1.86; 95% confidence interval, 0.91-3.83; P = .067). A significant benefit was, however, observed with CES for late-onset VAP (P = .03). Mortality and duration of ICU and hospital stay were similar in the 2 groups. The cost of suction catheters and gloves was significantly higher with CES (Rs 272 [US $5.81] vs Rs 138 [US $2.94], P < .0001). Nine patients need to be treated with CES to prevent 1 VAP (95% confidence interval, −0.7 to 22).

Conclusions

In the ICU setting in a developing country, CES may be advantageous in reducing the incidence of VAP, particularly late-onset VAP. These results mandate further studies in this setting before specific guidelines regarding the routine use of CES are proposed.     

注药式气管导管在术后ICU病人机械通气中的应用

目的 采用注药式气管导管对术后机械通气的ICU病人行气道表面麻醉，观察机械通气过程中病人对气管导管的耐受情况。方法 选择34例胸腹部手术、术后行机械通气12h以上的病人，随机分为两组，每组17例。对照组（C组）：经注药式气管导管气管内注射生理盐水；治疗组（T组）：经注药式气管导管气管内注射2％利多卡因。观察病人在机械通气12h内气管导管的耐受情况和镇静药物咪唑安定、芬太尼的给药次数及使用量的变化。结果 治疗组病人在机械通气12h内呛咳反应、高血压和心动过速的发生次数显著低于对照组（P〈0．05）；治疗组病人在机械通气12h内咪唑安定和芬太尼给药次数和使用量显著低于对照组（P〈0．05）。结论 使用注药式气管导管进行气道表面麻醉可以显著减轻气管导管引起的不适反应，减少ICU病人的镇静药物用量。     

A new device to remove obstruction from endotracheal tubes during mechanical ventilation in critically ill patients

Objective To evaluate the efficiency of a new device developed to remove obstructions from endotracheal tubes (ETT) in mechanically ventilated patients.Design Open study in mechanically ventilated sedated and paralyzed ICU patients.Setting General ICU and Laboratory of Respiratory Mechanics of the University of Rome La Sapienza.Patients 8 consecutive unselected mechanically ventilated, critically ill patients in which a partial obstruction of ETT was suspected on the basis of an increase of the peak inspiratory pressure (>20%) plus the difficult introduction of a standard suction catheter.Interventions Obstructions to ETT were removed with an experimental obstruction remover (OR)Measurements In vivo ETT airflow resistance (0.25; 0.5; 0.75; 1l/s) was evaluated before and after use of the OR; the work of breathing necessary to overcome ETT resistance (WOB_ett) was also evaluated before and after OR use.Results The use of OR significantly reduced in all patients the ETT in vivo resistance (From 5.5±2.3 to 2.9±0.5 cmH₂O/l/s at 0.25l/s,p<0.05; from 9±2.4 to 3.8±0.8 cmH₂O/l/s at 0.51l/s; from 12.2±3.5 to 5.7±1.2 cmH₂O/l/s at 0.75l/s; from 16.9±6 to 9.3±3.8 cmH₂O/l/s at 1l/s,p<0.01 respectively). Also the WOB_ett was significantly reduced after use of the OR (from 0.66±0.19 to 0.34±0.08 J/l;p<0.05)Conclusion This experimental device can be safely and successfully used to remove obstructions from the ETT lumen, without suspending mechanical ventilation, reducing the need for rapid ETT substitution in emergency and life-threatening situations.     

Evaluation of respiratory system resistance in mechanically ventilated patients: The role of the endotracheal tube

Objective To investigate the role played by the endotracheal tube (ETT) in the correct evaluation of respiratory system mechanics with the end inflation occlusion method during constant flow controlled mechanical ventilation.Setting General ICU, university of Rome La Sapienza.Patients 12 consecutive patients undergoing controlled mechanical ventilation.Methods We compared the values of minimal resistance of the respiratory system (i.e. airway resistance) (RRS min) obtained: i) subtracting the theoretical value of ETT resistance from the difference between P max and P1, measured on airway pressure tracings obtained from the distal end of the ETT; ii) directly measuring airway pressure 2 cm below the ETT, thus automatically excluding ETT resistance from the data.Results The values of RRS min obtained by measuring airway pressure below the ETT were significantly lower than those obtained by measuring airway pressure at the distal end of the ETT and subtracting the theoretical ETT resistance (4.5±2.8 versus 2.5±1.6 cm H₂O/l/s,p<0.01).Conclusion When precise measurements of ohmic resistances are required in mechanically ventilated patients, the measurements must be obtained from airways pressure data obtained at tracheal level. The in vivo positioning of ETT significantly increases the airflow resistance of the ETT.     

Value of clinical pulmonary infection score in critically ill children as a surrogate for diagnosis of ventilator-associated pneumonia

Rationale

Although the modified clinical pulmonary infection score (mCPIS) has been endorsed by national organizations, only a very few pediatric studies have assessed it for the diagnosis of ventilator-associated pneumonia (VAP).

Methods

Seventy children were prospectively included if they fulfilled the diagnosis criteria for VAP referenced by the Centers for Disease Control and Prevention. The primary outcome was performance of mCPIS calculated on day 1 to accurately identify VAP as defined by microbiological data.

Results

The data showed that an mCPIS of 6 or higher had a sensitivity of 94%, specificity of 50%, positive predictive value of 64%, negative predictive value of 90%, a positive likelihood ratio of 1.88, and a negative likelihood ratio of 0.11. The area under the receiver operating characteristic curve was 0.70. A positive posttest result increased the disease probability by 15.4%, whereas a negative test result reduced the probability by 38.6%. Patients with an mCPIS of 6 or higher had longer length of mechanical ventilation and pediatric intensive care unit stay compared with patients with an mCPIS lower than 6.

Conclusion

The mCPIS had a clinically acceptable performance, and it can be a helpful screening tool for VAP diagnosis. An mCPIS lower than 6 was highly able in distinguishing patients without VAP. Despite its high sensitivity and negative predictive value of this score, further studies are required to assess the use of mCPIS in guiding therapeutic decisions.     

Correlates of clinical failure in ventilator-associated pneumonia: insights from a large, randomized trial

PURPOSE: Our objective was to determine clinical variables measured at baseline and day 3 that may relate to failure of resolution of ventilator-associated pneumonia (VAP). MATERIALS AND METHODS: In patients with confirmed VAP derived from a large, randomized controlled trial comparing different modalities for the diagnosis and treatment of VAP, we identified risk factors associated with clinical failure. Clinical failure was prospectively defined in this trial as death, persistence of clinical and radiographic features of infection throughout the study period requiring additional antibiotics, superinfection, or relapsing infection. We examined the relationship between VAP resolution and clinical characteristics measured both at study enrollment and at day 3. We used logistic regression to identify independent factors associated with clinical failure and conducted a sensitivity analysis focusing only on patients who met the definition for clinical failure but who nonetheless survived until day 28. RESULTS: Of 563 subjects with VAP, 179 (31.8%) were classified as clinical failures. Death was the most common reason for clinical failure. At baseline, clinical failure patients were older, more severely ill, had been on mechanical ventilation for a longer period, and had higher Clinical Pulmonary Infection Score values and lower Pao2/Fio2 ratios. By day 3, patients defined as clinical failures remained more severely ill and continued to have worse oxygenation. In multivariate analysis, 4 factors were independently associated with clinical failure: older age, duration of ventilation before enrollment, presence of neurologic disease at admission, and failure of the Pao2/Fio2 ratio to improve by day 3. Repeating this multivariable model in only surviving patients suggested that persistence of fever was the only variable associated with clinical failure. CONCLUSIONS: Clinical characteristics correlate with eventual outcomes in VAP. Failure of the Pao2/Fio2 ratio and fever to improve are independently associated with clinical failure. We suggest that clinicians follow these measures and consider integrating them in their decisions as to when to reevaluate persons with VAP who are not improving.     

比阿培南治疗细菌性肺炎和尿路感染的多中心随机对照临床试验

目的评价比阿培南治疗细菌性肺炎和尿路感染的疗效和安全性。方法本研究为多中心、开放、随机对照试验,细菌性肺炎和尿路感染患者分别按中心分层随机接受比阿培南或美罗培南治疗。结果①比阿培南组和美罗培南组有效率分别为87.0%(107/123)和90.1%(109/121),其中两组细菌性肺炎有效率分别为90.0%(63/70)和91.9%(57/62),尿路感染有效率分别为83.0%(44/53)和88.1%(52/59);②两组细菌清除率分别为96.3%(77/80)和98.8%(79/80),其中肺炎细菌清除率分别为100%(42/42)和100%(39/39),尿路感染细菌清除率分别为92.1%(35/38)和97.6%(40/41);③两组不良反应发生率分别为4.7%(6/129)和3.1%(4/128),药物相关实验室异常发生率分别为17.1%(22/129)和19.5%(25/128),分别有2例(1.6%)和4例(3.1%)因不良反应终止治疗。经统计学分析两组的有效率、细菌清除率和不良反应发生率差异均无统计学意义。结论比阿培南治疗细菌性肺炎和尿路感染疗效确切,患者耐受性良好,其临床和细菌学疗效以及不良反应发生率均与对照药美罗培南相仿。     

Retention of the antibiotic teicoplanin on a hydromer-coated central venous catheter to prevent bacterial colonization in postoperative surgical patients

Objective Antibioticcoated intravascular catheters may be an effective means of decreasing bacterial colonization and subsequent catheter-related infection. The present study was designed to investigate the retention of the antibiotic teicoplanin on a hydromer-coated intravenous catheter and the effect of this antibiotic coating on catheter bacterial colonization.Design A prospective, randomized pilot study.Setting Operating rooms (ORs) and an intensive care unit (ICU) at a university hospital.Patients A consecutive group of 20 male patients undergoing major abdominal surgery.Interventions Control (C,n=10) or teicoplanin-coated (T;n=10) single-lumen central venous catheters were inserted before surgery in the OR. Catheters were withdrawn at the discretion of the physicians in the ICU after various periods.Measurements The teicoplanin content of the catheter material was assessed using a bioassay withBacillus subtilis after complete elution of the antibiotic from the catheter. Bacterial colonization was measured using a quanitative culture technique after the catheter lumen had been flushed and the catheter segments sonicated.Main results Nearly three-quarters of the initial teicoplanin coating (374±103 g; mean±SD) were released during the first day of catheterization, and after 36 h of intravenous catheterization, no antibiotic was retained on the catheter. No significant difference could be found either in the incidence of bacterial colonization between test (n=3) and control (n=4) catheters or in the number of colony-forming units (CFU) on the catheter segments (T, 263±104 CFU/cm; C, 372±294 CFU/cm; mean±SEM).Conclusion The retention of teicoplanin antibiotic coating on hydromer catheters is only short term if catheters are inserted intravenously. This may limit clinical antibacterial efficacy.     

Mechanical ventilation strategies and inflammatory responses to cardiac surgery: a prospective randomized clinical trial

Objective To examine whether postoperative mechanical ventilation with lower tidal volumes (V_T) has protective effects on inflammatory responses induced by cardiopulmonary bypass (CPB) surgery in smokers and nonsmokers.Design and setting Prospective, randomized, controlled clinical trial in the intensive care unit of a university hospital.Patients and participants We examined 44 patients (22 smokers, 22 nonsmokers) immediately after uncomplicated CPB surgery.Interventions Ventilation was applied for 6 h with either V_T of either 6 or 12 ml/kg ideal body weight.Measurements and results The time course of serum tumor necrosis factor (TNF) , interleukin (IL) 6, and IL-8 determined 0, 2, 4, and 6 h after randomization did not differ significantly between the ventilatory strategies. By contrast, in bronchoalveolar lavage fluids sampled after 6 h only TNF- levels were significantly higher in the high V_T group than the low V_T group (50±111 pg/ml vs. 1±7 pg/ml). IL-6 and IL-8 concentrations did not differ between groups. Subgroup analysis of patients with serum TNF- level higher than 0 pg/ml after surgery revealed lower TNF- serum levels during lower V_T ventilation. All observed effects were small, independent of patients history of smoking, and were not correlated with duration of ventilation and ICU stay.Conclusions Ventilation with lower V_T had no or only minor effect on systemic and pulmonary inflammatory responses in patients with healthy lungs after uncomplicated CPB surgery. Our data do not suggest a clinical benefit of using low V_T ventilation in these selected patients.This study was supported by grants from the BONFOR Forschungsförderung (project O-117.0006), University of Bonn, Germany, and from the Deutsche Forschungsgemeinschaft (Pu 219/1-1, and Uh 88/4-1), Bonn, Germany, and by departmental funding.     

Effects of three approaches to standardized oral hygiene to reduce bacterial colonization and ventilator associated pneumonia in mechanically ventilated patients: a randomised control trial

Background

Ventilator associated pneumonia remains an important concern in the intensive care unit (ICU). An increasing body of evidence shows that mortality and morbidity can be reduced by implementing a range of preventive strategies, including optimizing oral hygiene.

Aim

The aim of this feasibility study was to test two oral hygiene strategies on the effects of microbial colonization of dental plaque with respiratory pathogens (primary outcome) and incidence of ventilator associated pneumonia (secondary outcome).

Methods

A single blind randomised comparative study was conducted in a 20-bed adult intensive care unit in a university hospital. Patients with an expected duration of mechanical ventilation more than 48 h were eligible. Patients were randomised to one of three study regimens (Group A control, second hourly oral rinse with sterile water, Group B sodium bicarbonate mouth wash second hourly, and Group C twice daily irrigations with chlorhexidine 0.2% aqueous oral rinse and second hourly irrigations with sterile water). All study options included cleaning with a toothbrush and non foaming toothpaste.

Results

Data from a total of 109 patients were analyzed. Group A 43, Group B 33 and Group C 33 (mean age: 58 ± 17 years, simplified acute physiology score II: 44 ± 14 points). On admission no significant differences were found between groups for all clinical data. While Group B showed a greater trend to reduction in bacterial colonization no significant differences could be demonstrated at Day 4 of admission (p = 0.302). The incidence of ventilator associated pneumonia was evenly spread between Groups B and C (5%) while Group A was only 1%.

Conclusions

While a number of studies have advocated the use of various mouth rinses in reducing colonization of dental plaque a standardized oral hygiene protocol which includes the use of mechanical cleaning with a toothbrush may be a factor in the reduction of colonization of dental plaque with respiratory pathogens. This feasibility study provides data to inform future adequately powered studies.     

婴幼儿先天性心脏病术后呼吸机相关性肺炎病原菌分布及药敏变迁

目的 调查武汉市儿童医院婴幼儿先天性心脏病术后呼吸机相关性肺炎病原菌分布及耐药情况,为临床合理使用抗菌药物提供依据.方法 回顾性分析2010年1月至2012年11月武汉市儿童医院心脏外科婴幼儿先天心脏病术后并发呼吸机相关相关性肺炎病例,对此类患儿分离出的病原菌,采用VITEK2Jr全自动细菌鉴定及药敏分析系统鉴定细菌类别,纸片扩散(K2B)法进行药敏试验.对药敏结果采用WHONET 5.0系统软件进行分析.结果 2010年检出16株病原菌,革兰氏阴性菌9株(前两位是肺炎克雷伯杆菌18.75％,鲍曼氏不动杆菌12.5％);革兰氏阳性球菌6株(链球菌18.75％为主),真菌1株.2011年检出32株病原菌,革兰氏阴性菌24株(前三位是鲍曼氏不动杆菌31.25％,肺炎克雷伯杆菌25％,铜绿假单胞菌6.25％),革兰氏阳性球菌8株(肠球菌12.5％,链球菌6.25％).2012年检出42株病原菌,革兰氏阴性菌38株(肺炎克雷伯杆菌33.33％,鲍曼氏不动杆菌26.19％,铜绿假单胞菌21.42％),革兰氏阳性球菌4株(肠球菌4.76％为主).鲍曼氏不动杆菌对对阿米卡星、左氧氟沙星敏感率最高,但对美罗培南、亚胺培南耐药.肺炎克雷伯杆菌对阿米卡星、左氧氟沙星敏感最高,对头孢哌酮/舒巴坦、美罗培南、亚胺培南、复方新诺明、环丙沙星耐药.铜绿假单胞菌自2012年起仅对左氧氟沙星、哌拉西林/他唑巴坦敏感.革兰氏阳性球菌所占比例逐年降低,多以肠球菌及链球菌为主,葡萄球菌逐年减少,但未发现万古霉素耐药菌株.结论 婴幼儿先心病术后呼吸机相关性肺炎优势病原菌为革兰氏氏阴性菌,以肺炎克雷伯菌、鲍曼氏不动杆菌和铜绿假单胞菌为主,且耐药性呈增加趋势,临床应依据细菌病原学及耐药性资料,合理选择抗菌药物.     

Screening of ARDS patients using standardized ventilator settings: influence on enrollment in a clinical trial

Objectives The American–European consensus conference (AECC) definition for acute respiratory distress syndrome (ARDS) requires a PaO₂/F_IO₂200 mmHg, regardless of ventilator settings. We report the results of using standardized ventilator settings to screen and enroll ARDS patients in a clinical trial of high-frequency oscillatory ventilation (HFOV), including the impact on study enrollment, and potential effects on study outcome.Design Prospective cohort study.Setting Intensive care units in two teaching hospitals.Participants A consecutive sample of 41 patients with early ARDS by AECC criteria (baseline PaO₂/F_IO₂200) who met all other inclusion/exclusion criteria for the HFOV trial.Interventions Patients were placed on standardized ventilator settings (tidal volume 7–8 ml/kg, PEEP 10 cmH₂O, F_IO₂ 1.0), and the PaO₂/F_IO₂ was reassessed after 30 min.Results Seventeen patients (41.5%) had PaO₂/F_IO₂ ratios that remained 200 mmHg [Persistent ARDS; PaO₂/F_IO₂=94±36 (mean±SD)] and went on to inclusion in the HFOV study; however, in 24 patients (58.5%) the PaO₂/F_IO₂ was >200 mmHg [Transient ARDS; PaO₂/F_IO₂=310±74] and these patients were ineligible for the HFOV study. The ICU mortality was significantly greater (52.9 vs 12.5%; p=0.01) in the Persistent ARDS patients.Conclusions The use of these standardized ventilatory significantly impacted the PaO₂/F_IO₂ ratio and therefore the ARDS prevalence and trial enrollment. These results have effects on the evaluation of the current ARDS literature and conduct of clinical trials in ARDS and hence consideration should be given to the use of standardized ventilatory settings in future ARDS trials.Electronic Supplementary Material Supplementary Material is available in the online version of this article at     

Impact of systemic corticosteroids on the clinical course and outcomes of patients with severe community-acquired pneumonia: a cohort study

Introduction

Our aim was to evaluate the impact of corticosteroids on clinical course and outcomes of patients with severe community-acquired pneumonia (CAP) requiring invasive mechanical ventilation.

Methods

This was a cohort study of patients with severe CAP from 2 intensive care units in tertiary hospitals in Brazil and Portugal.

Results

A total of 111 patients were included (median age, 69 years; 56% men; 34% hospital mortality). Corticosteroids were prescribed in 61 (55%) patients. Main indications for their use were bronchospasm (52.5%) and septic shock (36%). Mortality rate of patients treated with and without corticosteroids was comparable (29.5% vs 32%, P = .837). No significant differences were observed on clinical course from day 1 to day 7 as assessed by the Sequential Organ Failure Assessment score (P = .95). Furthermore, C-reactive protein declined similarly in both groups (P = .147). In a multivariate analysis, mortality was associated with older age and higher Acute Physiology and Chronic Health Evaluation II score.

Conclusions

In patients with severe CAP requiring invasive mechanical ventilation, adjunctive therapy with corticosteroids did not influence intensive care unit and hospital mortality. In addition, no changes were observed on weaning from vasopressors, on recovery from organ failure/dysfunction as assessed by the Sequential Organ Failure Assessment score, as well as on C-reactive protein course.     

Patterns of colonization by Pseudomonas aeruginosa in intubated patients: a 3-year prospective study of 1,607 isolates using pulsed-field gel electrophoresis with implications for prevention of ventilator-associated pneumonia

Objective To identify routes and patterns of colonization with Pseudomonas aeruginosa in intubated patients to design strategies of prevention for respiratory infection.Design and setting Prospective and observational study in the 16-bed intensive care unit of a teaching hospital.Patients and participants Ninety-eight intubated patients were investigated over a 3-year period. Those ventilated less than 72 h were excluded.Measurements and results Samples from the tap water from each patients room, stomach, oropharynx, subglottic secretions, trachea, and rectum were collected when the patient was intubated, and then three times per week. Pulsed-field gel electrophoresis was performed to type the strains. We identified 1,607 isolates pertaining to 35 different pulsotypes. Overall 54.2% of patients presented colonization, and tracheal colonization was present in 30.5%. Ten patients had colonization at intubation, and four of these developed ventilator-associated pneumonia (VAP) after a mean of 4±2 days. ICU-acquired colonization occurred in 31 patients, and 4 of these developed VAP after a median of 10±5 days. P. aeruginosa was isolated from the rooms tap water in 62.4% of samples. More than 90% of tap water samples had pulsotypes 1 and 2, which were frequently isolated in the stomach (59%) but were only rarely associated with VAP.Conclusions Although colonization/infection with P. aeruginosa in intubated patients tends to be endogenous, exogenous sources should not be ruled out. A combination of early identification (and eradication) of airways colonization by P. aeruginosa plus infection control measures targeted to reduce cross-contamination should be the basis to prevent pulmonary infection.This work was supported in part by a grant from the FIS 96/146     

The effects of statin therapy on inflammatory cytokines in patients with bacterial infections: a randomized double-blind placebo controlled clinical trial

Objective  To determine if statin therapy reduces the incidence of severe sepsis and the levels of inflammatory cytokines in patients with acute bacterial infection. Design  Double-blind placebo controlled randomized clinical trial. Setting  Department of medicine and medical intensive care unit in a tertiary university medical center. Patients and participants  A total of 83 patients with suspected or documented bacterial infection were enrolled. We randomly assigned 42 patients to receive 40 mg of simvastatin orally, followed by 20 mg of simvastatin, and 41 to receive matching placebo. Measurements and results  The study was prematurely terminated due to slow recruitment rate. Here we report the analysis of the secondary outcome: change in cytokines levels at 72 h. Both groups were evenly matched in terms of co-morbidity and severity of illness on admission. Four of the 83 patients enrolled developed severe sepsis, two in each group. No difference was observed in other clinical variables and there were no mortalities. Cytokine levels were randomly assessed in 40 patients (20 in each group). Both TNF-α and IL-6 levels were significantly reduced in the simvastatin group (p = 0.02 and p = 0.02, respectively), while no such difference was observed in the placebo group (p = 0.35 and 0.39, respectively). Conclusions  Statin therapy may be associated with a reduction in the levels of inflammatory cytokines in patients with acute bacterial infections. Large controlled trials will determine if this reduction will translate into a clinical benefit. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.