National nosocomial infection surveillance system: from benchmark to bedside in trauma patients

Surveillance of ventilator associated pneumonia in a network of indian hospitals using modified definitions: a pilot study

Background

Ventilator-associated pneumonia (VAP) is a major cause of morbidity and mortality in patients receiving mechanical ventilation in India. Surveillance of VAP is essential to implement data-based preventive measures. Implementation of ventilator-associated events (VAE) criteria for surveillance has major constraints for low resource settings, which can lead to significant underreporting. Surveillance of VAP using common protocols in a large network of hospitals would give meaningful estimates of the burden of VAP in low resource settings. This study leverages a previously established healthcare-associated infections (HAI) surveillance network to develop and test a modified VAP definition adjusted for Indian settings.

Methods

In this observational pilot study, thirteen hospitals from the existing HAI surveillance network were selected for developing and testing a modified VAP definition between February 2021 and April 2023. The criteria used for diagnosing VAP were adapted from the CDC's Pediatric VAP definition and modified to cater to the needs of Indian hospitals. Designated nurses recorded each VAP event in a case report form (CRF) and also collected denominator data. The data was entered into an indigenously developed database for validation and analysis. At the time of data analysis, a questionnaire was sent to sites to get feedback on the performance of the modified VAP definitions.

Findings

Out of 133,445 patient days and 40,533 ventilator days, 261 VAP events were recorded, with an overall VAP rate of 6.4 per 1000 ventilator days and a device utilization ratio (DUR) of 0.3. A total of 344 organisms were reported from the VAP events. Of these, Acinetobacter spp (29.6%, 102) was the most frequent, followed by Klebsiella spp (26.7%, 92). Isolates of Acinetobacter spp (98%) and Enterobacterales (85.5%) showed very high resistance against Carbapenem. Colistin resistance was observed in 6% of Enterobacterales and 3.2% of Acinetobacter spp.

Interpretation

Data from this pilot study needs to validated in the larger Indian HAI surveillance network so that it can help in wider implementation of this protocol in order to assess its applicability p VAP across India.

Funding

This work was supported by a grant received from the Indian Council of Medical Research (code I-1203).

Quantitative correlation of colony forming units of Acinetobacter baumannii obtained from endotracheal tube aspirate culture with clinical pulmonary infection score

Background and Aims:

Ventilator-associated pneumonia (VAP) is the most common healthcare-associated infection in adult critical care units. The reason behind the different levels of severity and the outcome in different individuals is not established yet.Co-morbidities and age may be a valid reason.In an attempt to find out the reason behind the different levels of severity of VAP in different individuals, we conducted a studywith the primary objective being to assess the quantitative correlation between the colony forming units (CFU) of Acinetobacter baumannii in the endotracheal tube aspirate and the Clinical Pulmonary Infection Score (CPIS) in mechanically ventilated patients without co-morbidities. The secondary objective was to see whether the severity of VAP depends on the number of CFU(>10⁵/ml).

Methods:

This observational study was conducted in a 27-bedded intensive care unit of a tertiary care hospital in northern India. Endotracheal tube aspirate was collected from patients with suspected VAP.A total of 81 patients without any prior co-morbidity and having Acinetobacter baumannii in their endotracheal tube aspirate were included in the study group. Quantification of Acinetobacter baumannii was done by counting CFU.The CPIS was calculated for all Acinetobacter baumannii positive patients. Correlation between CFU of Acinetobacter baumannii and CPIS was assessed using Spearman's Rho correlation coefficient.

Results:

Among 81 patients having Acinetobacter baumannii infection, only 61.9% had a CPIS >4. There was an insignificant correlation between the quantity of CFUs of Acinetobacter baumannii and CPIS (P value = 0.784).

Conclusion:

Number of CFU >10⁵/ml in an endotracheal tube aspirate culture bears no relation to the severity of VAP as predicted by the CPIS.

Concordance between the National Healthcare Safety Network (NHSN) Surveillance Criteria and Clinical Pulmonary Infection Score (CPIS) Criteria for Diagnosis of Ventilator-associated Pneumonia (VAP)

Background: Ventilator-associated pneumonia (VAP) is one of the most common hospital-acquired infections among mechanically ventilated patients and the incidence rates are widely used as an index of quality of care given in an ICU. Since there is no gold standard method available to diagnose VAP, the incidence rate varies based on different criteria used for calculation. Therefore, we conducted a study to determine the concordance between the National Healthcare Safety Network (NHSN) surveillance criteria and clinical pulmonary infection score (CPIS) criteria for the diagnosis of VAP.

Materials and methods: This was a prospective study that evaluated patients in the medical intensive care units (MICUs) of a tertiary care hospital, India, who were intubated for >48 hours between October 2018 and September 2019. All the patients (n = 273) were followed up daily and assessed using both CPIS and NHSN surveillance criteria for diagnosing VAP.

Results: Of these 273 patients, 93 patients (34.1%) had VAP according to CPIS criteria as compared with 33 patients (12.1%) using the NHSN criteria. The corresponding rates of VAP were 39.59 vs 11.53 cases per 1,000 ventilator days, respectively. The agreement of the two sets of criteria was fairly good (kappa statistics, 0.42)

Conclusion: The NHSN surveillance criteria have a lower sensitivity in detecting VAP cases and have to be modified to achieve better results.

How to cite this article: Gunalan A, Sistla S, Sastry AS, Venkateswaran R. Concordance between the National Healthcare Safety Network (NHSN) Surveillance Criteria and Clinical Pulmonary Infection Score (CPIS) Criteria for Diagnosis of Ventilator-associated Pneumonia (VAP). Indian J Crit Care Med 2021;25(3):296–298.

The nitric oxide donor, (Z)-1-[N-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate (DETA-NONOate/D-NO), increases survival by attenuating hyperoxia-compromised innate immunity in bacterial clearance in a mouse model of ventilator-associated pneumonia

Mechanical ventilation (MV) with supraphysiological levels of oxygen (hyperoxia) is a life-saving therapy for the management of patients with respiratory distress. However, a significant number of patients on MV develop ventilator-associated pneumonia (VAP). Previously, we have reported that prolonged exposure to hyperoxia impairs the capacity of macrophages to phagocytize Pseudomonas aeruginosa (PA), which can contribute to the compromised innate immunity in VAP. In this study, we show that the high mortality rate in mice subjected to hyperoxia and PA infection was accompanied by a significant decrease in the airway levels of nitric oxide (NO). Decreased NO levels were found to be, in part, due to a significant reduction in NO release by macrophages upon exposure to PA lipopolysaccharide (LPS). Based on these findings, we postulated that NO supplementation should restore hyperoxia-compromised innate immunity and decrease mortality by increasing the clearance of PA under hyperoxic conditions. To test this hypothesis, cultured macrophages were exposed to hyperoxia (95% O₂) in the presence or absence of the NO donor, (Z)-1-[N-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate (DETA-NONOate/D-NO). Interestingly, D-NO (up to 37.5 µM) significantly attenuated hyperoxia-compromised macrophage migratory, phagocytic, and bactericidal function. To determine whether the administration of exogenous NO enhances the host defense in bacteria clearance, C57BL/6 mice were exposed to hyperoxia (99% O₂) and intranasally inoculated with PA in the presence or absence of D-NO. D-NO (300 µM-800 µM) significantly increased the survival of mice inoculated with PA under hyperoxic conditions, and significantly decreased bacterial loads in the lung and attenuated lung injury. These results suggest the NO donor, D-NO, can improve the clinical outcomes in VAP by augmenting the innate immunity in bacterial clearance. Thus, provided these results can be extrapolated to humans, NO supplementation may represent a potential therapeutic strategy for preventing and treating patients with VAP.

Multicentre randomised controlled trial to investigate the usefulness of continuous pneumatic regulation of tracheal cuff pressure for reducing ventilator-associated pneumonia in mechanically ventilated severe trauma patients: the AGATE study protocol

INTRODUCTION

Severe trauma represents the leading cause of mortality worldwide. While 80% of deaths occur within the first 24 hours after trauma, 20% occur later and are mainly due to healthcare-associated infections, including ventilator-associated pneumonia (VAP). Preventing underinflation of the tracheal cuff is recommended to reduce microaspiration, which plays a major role in the pathogenesis of VAP. Automatic devices facilitate the regulation of tracheal cuff pressure, and their implementation has the potential to reduce VAP. The objective of this work is to determine whether continuous regulation of tracheal cuff pressure using a pneumatic device reduces the incidence of VAP compared with intermittent control in severe trauma patients.

METHODS AND ANALYSIS

This multicentre randomised controlled and open-label trial will include patients suffering from severe trauma who are admitted within the first 24 hours, who require invasive mechanical ventilation to longer than 48 hours. Their tracheal cuff pressure will be monitored either once every 8 hours (control group) or continuously using a pneumatic device (intervention group). The primary end point is the proportion of patients that develop VAP in the intensive care unit (ICU) at day 28. The secondary end points include the proportion of patients that develop VAP in the ICU, early (≤7 days) or late (>7 days) VAP, time until the first VAP diagnosis, the number of ventilator-free days and antibiotic-free days, the length of stay in the ICU, the proportion of patients with ventilator-associated events and that die during their ICU stay.

ETHICS AND DISSEMINATION

This protocol has been approved by the ethics committee of Poitiers University Hospital, and will be carried out according to the principles of the Declaration of Helsinki and the Good Clinical Practice guidelines. The results of this study will be disseminated through presentation at scientific conferences and publication in peer-reviewed journals.

TRIAL REGISTRATION

Clinical Trials NCT02534974.

Perioperative Predictors of Extubation Failure and the Effect on Clinical Outcome After Infratentorial Craniotomy

BACKGROUND The purpose of the study was to analyze the risk factors for failed extubation in subjects submitted to infratentorial craniotomy. MATERIAL AND METHODS Patients aged over 18 years who received infratentorial craniotomy for brain tumor resection were consecutively included in this study. Perioperative variables were collected and analyzed. Univariate analyses and multiple logistic regression were used to derive factors related to failed extubation. Patients had follow-up care until either out of hospital or death. RESULTS Throughout the course of the study, 2118 patients were eligible and 94 (4.4%) suffered from extubation failure at some point during their hospital stay. Five factors were recognized as independent risk factors for postoperative failed extubation: craniotomy history, preoperative lower cranial nerve dysfunction, tumor size, tumor position, and maximum change in blood pressure (BP) during the operation. Failed extubation was related to a higher incidence rate of pneumonia, mortality, unfavorable Glasgow Outcome Scale score, longer stay in the neuro-intensive care unit (ICU) and hospitalization, and higher hospitalization costs compared with successful extubation. CONCLUSIONS History of craniotomy, preoperative lower cranial nerve dysfunction, tumor size, tumor position, and maximum change in BP during the operation were independent risk factors related to postoperative failed extubation in patients submitted to infratentorial craniotomy. Extubation failure raises the incidences of postoperative pneumonia, mortality, and higher hospitalization costs, and prolongs neuro-ICU and postoperative length of stay.

Comparison between a clinical diagnosis method and the surveillance technique of the Center for Disease Control and Prevention for identification of mechanical ventilator-associated pneumonia

Objective

>To evaluate the agreement between a new epidemiological surveillance method of the Center for Disease Control and Prevention and the clinical pulmonary infection score for mechanical ventilator-associated pneumonia detection.

Methods

This was a prospective cohort study that evaluated patients in the intensive care units of two hospitals who were intubated for more than 48 hours between August 2013 and June 2014. Patients were evaluated daily by physical therapist using the clinical pulmonary infection score. A nurse independently applied the new surveillance method proposed by the Center for Disease Control and Prevention. The diagnostic agreement between the methods was evaluated. A clinical pulmonary infection score of ≥ 7 indicated a clinical diagnosis of mechanical ventilator-associated pneumonia, and the association of a clinical pulmonary infection score ≥ 7 with an isolated semiquantitative culture consisting of ≥ 10⁴ colony-forming units indicated a definitive diagnosis.

Results

Of the 801 patients admitted to the intensive care units, 198 required mechanical ventilation. Of these, 168 were intubated for more than 48 hours. A total of 18 (10.7%) cases of mechanical ventilation-associated infectious conditions were identified, 14 (8.3%) of which exhibited possible or probable mechanical ventilatorassociated pneumonia, which represented 35% (14/38) of mechanical ventilator-associated pneumonia cases. The Center for Disease Control and Prevention method identified cases of mechanical ventilator-associated pneumonia with a sensitivity of 0.37, specificity of 1.0, positive predictive value of 1.0, and negative predictive value of 0.84. The differences resulted in discrepancies in the mechanical ventilator-associated pneumonia incidence density (CDC, 5.2/1000 days of mechanical ventilation; clinical pulmonary infection score ≥ 7, 13.1/1000 days of mechanical ventilation).

Conclusion

The Center for Disease Control and Prevention method failed to detect mechanical ventilatorassociated pneumonia cases and may not be satisfactory as a surveillance method.

Ventilator-Associated Pneumonia in Trauma Patients: Different Criteria, Different Rates

BACKGROUND

No consensus exists regarding the definition of ventilator-associated pneumonia (VAP). Even within a single institution, inconsistent diagnostic criteria result in conflicting rates of VAP. As a Level 1 trauma center participating in the Trauma Quality Improvement Project (TQIP) and the National Healthcare Safety Network (NHSN), our institution showed inconsistencies in VAP rates depending on which criteria was applied. The purpose of this study was to compare VAP definitions, defined by culture-based criteria, National Trauma Data Bank (NTDB) and NHSN, using incidence in trauma patients.

METHODS

A retrospective chart review of consecutive trauma patients who were diagnosed with VAP and met pre-determined inclusion and exclusion criteria admitted to our rural, 861-bed, Level 1 trauma and tertiary care center between January 2008 and December 2011 was performed. These patients were identified from the National Trauma Registry of the American College of Surgeons (NTRACS) database and an in-house infection control database. Ventilator-associated pneumonia diagnosis criteria defined by the U.S. Center for Disease Control and Prevention (used by the NHSN), the NTDB, and our institutional, culture-based criteria gold standard were compared among patients.

RESULTS

Two hundred seventy-nine patients were diagnosed with VAP (25.4% met NHSN criteria, 88.2% met NTDB, and 76.3% met culture-based criteria). Only 58 (20.1%) patients met all three criteria. When NHSN criteria were compared with culture-based criteria, NHSN showed a high specificity (92.5%) and low sensitivity (28.2%). The positive predictive value (PPV) was 84.5%, but the negative predictive value (NPV) was 47.1%. The agreement between the NHSN and the culture-based criteria was poor (κ = 0.18). Conversely, the NTDB showed a lower specificity (57.8%), but greater sensitivity (86.4%) compared with culture-based criteria. The PPV and NPV were both 74% and the two criteria showed fair agreement (κ = 0.41).

CONCLUSIONS

The lack of standard diagnostic criteria for VAP resulted in variable reporting to different agencies. Emphasis on establishing a consensus VAP definition should be undertaken.

A prospective evaluation of ventilator-associated conditions and infection-related ventilator-associated conditions

BACKGROUND

The Centers for Disease Control and Prevention has shifted policy away from using ventilator-associated pneumonia (VAP) and toward using ventilator-associated conditions (VACs) as a marker of ICU quality. To date, limited prospective data regarding the incidence of VAC among medical and surgical ICU patients, the ability of VAC criteria to capture patients with VAP, and the potential clinical preventability of VACs are available.

METHODS

This study was a prospective 12-month cohort study (January 2013 to December 2013).

RESULTS

We prospectively surveyed 1,209 patients ventilated for ≥ 2 calendar days. Sixty-seven VACs were identified (5.5%), of which 34 (50.7%) were classified as an infection-related VAC (IVAC) with corresponding rates of 7.0 and 3.6 per 1,000 ventilator days, respectively. The mortality rate of patients having a VAC was significantly greater than that of patients without a VAC (65.7% vs 14.4%, P < .001). The most common causes of VACs included IVACs (50.7%), ARDS (16.4%), pulmonary edema (14.9%), and atelectasis (9.0%). Among IVACs, 44.1% were probable VAP and 17.6% were possible VAP. Twenty-five VACs (37.3%) were adjudicated to represent potentially preventable events. Eighty-six episodes of VAP occurred in 84 patients (10.0 of 1,000 ventilator days) during the study period. The sensitivity of the VAC criteria for the detection of VAP was 25.9% (95% CI, 16.7%-34.5%).

CONCLUSIONS

Although relatively uncommon, VACs are associated with greater mortality and morbidity when they occur. Most VACs represent nonpreventable events, and the VAC criteria capture a minority of VAP episodes.

Study of ventilator-associated pneumonia in a pediatric intensive care unit

OBJECTIVES

To determine the incidence, etiology, risk factors and outcome of ventilator associated pneumonia (VAP) among mechanically ventilated patients.

METHODS

All PICU patients who were mechanically ventilated for >48 h were consecutively enrolled. The development of VAP was defined by the radiological and clinical criteria described by the Center for Disease Control and Prevention/National Nosocomial Infection Surveillance (CDC/NNIS) (2003). The risk factors for VAP were determined by univariate and multivariate analysis using appropriate statistical methods.

RESULTS

The median age of the subjects (N = 232) was nine mo with a male to female ratio of 1.3:1. Of 232 subjects enrolled, there were 15 episodes of VAP in 14 patients (frequency of 6.03 %) with a mean VAP rate of 6.3/1,000 ventilator days. Eight of the 15 VAP episodes showed positive endotracheal culture with Gram negative organisms as the predominant isolate with Acinetobacter being the commonest organism isolated (62.5 %). Neuromuscular disease (P = 0.005), histamine-2 receptor blockers (P = 0.0001), tracheostomy (P = 0.0001), and positive blood culture growth (P = 0.0008) were found to be significantly associated with VAP (univariate analysis). VAP patients had a significantly longer duration of mechanical ventilation (22.5 vs. 5 median days; P < 0.001), longer PICU stay (23.25 vs. 6.5 median days; P < 0.001) and longer hospital stay (43.75 vs. 13.25 median days; P < 0.001). On multivariate analysis, only positive blood culture growth was a risk factor for VAP. The mortality rate of VAP was 42.8 % (not higher than those without VAP).

CONCLUSIONS

Frequency of VAP was 6.03 % with neuromuscular disease, histamine-2 receptor blockers, tracheostomy and positive blood culture being risk factors for VAP.

Factors influencing delayed extubation after infratentorial craniotomy for tumour resection: a prospective cohort study of 800 patients in a Chinese neurosurgical centre

OBJECTIVES

To investigate prospectively the rate of, and factors influencing, delayed extubation following infratentorial craniotomy in a Chinese neurosurgical centre.

METHODS

Patients undergoing infratentorial craniotomy for tumour resection were prospectively enrolled and stratified according to whether extubation was attempted in the operating theatre (early extubation) or not (delayed extubation). Pre- and intraoperative variables were collected and analysed. Multiple logistic regression analysis was performed, to identify factors related to delayed extubation.

RESULTS

The study included 800 patients, 398 (49.8%) of whom underwent delayed extubation. The overall rate of extubation failure was 3.6%. Independent factors related to delayed extubation were: preoperative lower cranial nerve dysfunction; hydrocephalus; tumour location; duration of surgery ≥ 6 h; estimated blood loss ≥ 1000 ml. Compared with patients in the early extubation group, those in the delayed extubation group had a higher rate of pneumonia, longer intensive care unit and postoperative hospital stays, and higher hospitalization costs.

CONCLUSIONS

Brain stem and lower cranial nerve function were the main factors affecting extubation decision-making. Further research is required, to establish criteria for delayed extubation following infratentorial craniotomy.

Ventilator-associated pneumonia rates at major trauma centers compared with a national benchmark: a multi-institutional study of the AAST

BACKGROUND

Ventilator-associated pneumonia (VAP) rates reported by the National Healthcare Safety Network (NHSN) are used as a benchmark and quality measure, yet different rates are reported from many trauma centers. This multi-institutional study was undertaken to elucidate VAP rates at major trauma centers.

METHODS

VAP rate/1,000 ventilator days, diagnostic methods, institutional, and aggregate patient data were collected retrospectively from a convenience sample of trauma centers for 2008 and 2009 and analyzed with descriptive statistics.

RESULTS

At 47 participating Level I and II centers, the pooled mean VAP rate was 17.2 versus 8.1 for NHSN (2006-2008). Hospitals' rates were highly variable (range, 1.8-57.6), with 72.3% being above NHSN's mean. Rates differed based on who determined the rate (trauma service, 27.5; infection control or quality or epidemiology, 11.9; or collaborative effort, 19.9) and the frequency with which VAP was excluded based on aspiration or diagnosis before hospital day 5. In 2008 and 2009, blunt trauma patients had higher VAP rates (17.3 and 17.6, respectively) than penetrating patients (11.0 and 10.9, respectively). More centers used a clinical diagnostic strategy (57%) than a bacteriologic strategy (43%). Patients with VAP had a mean Injury Severity Score of 28.7, mean Intensive Care Unit length of stay of 20.8 days, and a 12.2% mortality rate. 50.5% of VAP patients had a traumatic brain injury.

CONCLUSIONS

VAP rates at major trauma centers are markedly higher than those reported by NHSN and vary significantly among centers. Available data are insufficient to set benchmarks, because it is questionable whether any one data set is truly representative of most trauma centers. Application of a single benchmark to all centers may be inappropriate, and reliable diagnostic and reporting standards are needed. Prospective analysis of a larger data set is warranted, with attention to injury severity, risk factors specific to trauma patients, diagnostic method used, VAP definitions and exclusions, and reporting guidelines.

LEVEL OF EVIDENCE

III, prognostic study.

Ventilator-Associated Pneumonia: Depends on Your Definition

Reduction of hospital-acquired infections is a patient safety goal and regularly monitored by Performance Improvement committees. There is discordance between the ventilator-associated pneumonia (VAP) rate reported by the Infection Control Committee (ICC) and that observed by our Trauma Service. To investigate this difference, a retrospective evaluation of cases of VAP diagnosed on a single service was undertaken. A prospectively collected database was queried for VAP in intensive care unit patients between January 2010 and June 2011. This was compared with the list of mechanically ventilated patients provided by the ICC. Comparison for criteria used to diagnose pneumonia, ventilator day of the diagnosis, was recorded. The ICC identified two VAPs from 136 potential patients compared with the Trauma Service identifying 36 VAPs. A difference in diagnostic criteria between the ICC and the Trauma Service focused on use of the National Nosocomial Infection Survey (NNIS) algorithm versus quantitative microbiology from bronchoalveolar lavage specimens. Thirty-five of 36 Trauma Service VAPs were not identified as VAPs by the NNIS algorithm as a result of the chest radiographs. Application of differing definitions of VAP results in markedly different VAP rates. The difference has significant implications as infection rates are increasingly reported as a quality metric.

Association between illness severity and timing of initial enteral feeding in critically ill patients: a retrospective observational study

Background

Early enteral nutrition is recommended in cases of critical illness. It is unclear whether this recommendation is of most benefit to extremely ill patients. We aim to determine the association between illness severity and commencement of enteral feeding.

Methods

One hundred and eight critically ill patients were grouped as “less severe” and “more severe” for this cross-sectional, retrospective observational study. The cut off value was based on Acute Physiology and Chronic Health Evaluation II score 20. Patients who received enteral feeding within 48 h of medical intensive care unit (ICU) admission were considered early feeding cases otherwise they were assessed as late feeding cases. Feeding complications (gastric retention/vomiting/diarrhea/gastrointestinal bleeding), length of ICU stay, length of hospital stay, ventilator-associated pneumonia, hospital mortality, nutritional intake, serum albumin, serum prealbumin, nitrogen balance (NB), and 24-h urinary urea nitrogen data were collected over 21 days.

Results

There were no differences in measured outcomes between early and late feedings for less severely ill patients. Among more severely ill patients, however, the early feeding group showed improved serum albumin (p = 0.036) and prealbumin (p = 0.014) but worsened NB (p = 0.01), more feeding complications (p = 0.005), and prolonged ICU stays (p = 0.005) compared to their late feeding counterparts.

Conclusions

There is a significant association between severity of illness and timing of enteral feeding initiation. In more severe illness, early feeding was associated with improved nutritional outcomes, while late feeding was associated with reduced feeding complications and length of ICU stay. However, the feeding complications of more severely ill early feeders can be handled without significantly affecting nutritional intake and there is no eventual difference in length of hospital stay or mortality between groups. Consequently, early feeding shows to be a more beneficial nutritional intervention option than late feeding in patients with more severe illness.

A clinical description of extubation failure in patients with primary brain injury

BACKGROUND

Patients with acute brain injury but normal lung function are often intubated for airway protection, but extubation often fails. Currently, no clinical data exist that describe the events leading to extubation failure in this population. We examined the extubation failure rate, reintubation rate, and clinical characteristics of patients whose reason for intubation was a primary neurological injury. We then identified the clinical characteristics of those patients with primary brain injury who were reintubated.

METHODS

We conducted a retrospective review of patients admitted to the neurocritical care unit of a tertiary care hospital from January 2002 to March 2007.

RESULTS

Of 1,265 patients who were intubated because of primary neurological injury of brain, spinal cord, or peripheral nerve, 25 (2%) died before extubation and 767 (61%) were successfully extubated. Tracheostomies were placed in 181 (14%) patients, of which, 77 (6.1%) were completed before a trial of extubation and 104 (8.2%) after extubation failure. A total of 129 (10%) patients were reintubated; 77 (6.1%) were reintubated within 72 h, meeting the definition of extubation failure. The other 52 (4.1%) were intubated after 72 h usually in the setting of pneumonia or decreased mental status. Ninety-nine of the patients reintubated had primary brain injury and resulting encephalopathy. All were successfully reintubated. Most patients intubated as a result of a primary brain injury (981) were successfully extubated. The most common clinical scenario leading to reintubation in these encephalopathic patients was respiratory distress associated with altered mental status [59 patients (59%)]. These patients usually had atelectasis and decreased minute ventilation, independent of fever, pneumonia, aspiration, and increased work of breathing [39 patients (39%)].

CONCLUSION

The extubation failure rate in our neurocritical care unit is low. In patients with encephalopathy and primary brain injury who were reintubated, respiratory distress caused by altered mental status was the most common cause of reintubation. These patients demonstrated signs disrupted ventilation usually with periods of prolonged hypoventilation. Increased work of breathing from lung injury due to pneumonia or aspiration was not the most common cause of reintubation in this population.

Daily multidisciplinary rounds to implement the ventilator bundle decreases ventilator-associated pneumonia in trauma patients: but does it affect outcome?

BACKGROUND

The incidence of ventilator-associated pneumonia (VAP) in trauma patients can be decreased with use of the ventilator bundle (VAPB). Our VAP rate remained high despite the adoption of the VAPB. To better implement the VAPB, a multidisciplinary team composed of the surgical intensive care unit (SICU) nursing staff, physician, and respiratory therapist reviewed briefly a checklist of VAPB goals for each patient before morning attending rounds. We hypothesized that such daily goal rounds (GR) focused on the VAPB would decrease the VAP rate.

METHODS

A pre-GR ten-month period (November 2006 to August 2007) was compared with the ten-month period (September 2007 to June 2008) with daily GRs. The occurrence of VAPs was tallied prospectively in all intubated trauma patients using the National Nosocomial Infection Surveillance criteria. Patient characteristics and outcome data were obtained from our trauma registry and medical records. Patient characteristics were similar in the 85 pre-GR patients and the 89 GR patients.

RESULTS

The number of VAPs decreased 67% in the GR patients (15 pre-GR vs. 5 GR; p=0.02); however, the all-cause mortality rate remained similar (16.5% vs. 21.3%; p=0.41). When patients were divided into those with and without VAP, there was a significant increase in mean ventilator, SICU, and hospital days in patients with VAP (p=0.01 for all). There were only two deaths among trauma patients with VAP.

CONCLUSION

Daily multidisciplinary GRs focused on the VAPB can decrease the incidence of VAP significantly in trauma patients. Ventilator-associated pneumonia correlated with extended mean ventilator, SICU, and hospital days. Interestingly, despite a significant decrease in VAP, a decrease in the mortality rate was not observed. Given the small number of deaths in the VAP cohort, this study has insufficient statistical power to elucidate the true impact of GR intervention or VAP on the mortality rate in trauma patients.

Errors in Administrative-Reported Ventilator-Associated Pneumonia Rates: Are Never Events Really So?

Ventilator-associated pneumonia (VAP) is a common problem in an intensive care unit (ICU), although the incidence is not well established. This study aims to compare the VAP incidence as determined by the treating surgical intensivist with that detected by the hospital Infection Control Service (ICS). Trauma and surgical patients admitted to the surgical critical care service were prospectively evaluated for VAP during a 5-month time period. Collected data included the surgical intensivist's clinical VAP (SIS-VAP) assessment using Centers for Disease Control and Prevention (CDC) VAP criteria. As part of the hospital's VAP surveillance program, these patients’ medical records were also reviewed by the ICS for VAP (ICS-VAP) using the same CDC VAP criteria. All patients suspected of having VAP underwent bronchioalveolar lavage (BAL). The SIS-VAP and ICS-VAP were then compared with BAL-VAP. Three hundred twenty-nine patients were admitted to the ICU during the study period. One hundred thirty-three were intubated longer than 48 hours and comprised our study population. Sixty-two patients underwent BAL evaluation for the presence of VAP on 89 occasions. SIS-VAP was diagnosed in 38 (28.5%) patients. ICS-VAP was identified in 11 (8.3%) patients ( P < 0.001). The incidence of VAP by BAL criteria was 23.3 per cent. When compared with BAL, SIS-VAP had 61.3 per cent sensitivity and ICS-VAP had 29 per cent sensitivity. VAP rates reported by hospital administrative sources are significantly less accurate than physician-reported rates and dramatically underestimate the incidence of VAP. Proclaiming VAP as a never event for critically ill for surgical and trauma patients appears to be a fallacy.

Evidence for quality indicators to evaluate adult trauma care: a systematic review

OBJECTIVE

Multiple quality indicators are available to evaluate adult trauma care, but their characteristics and outcomes have not been systematically compared. We sought to systematically review the evidence about the reliability, validity, and implementation of quality indicators for evaluating trauma care.

DATA SOURCES

Search of MEDLINE, EMBASE, CINAHL, and The Cochrane Library up to January 14, 2009; the Gray Literature; select journals by hand; reference lists; and articles recommended by experts in the field.

STUDY SELECTION

Studies were selected that evaluated the reliability, validity, or the impact of one or more quality indicators on the quality of care delivered to patients ≥ 18 yrs of age with a major traumatic injury.

DATA EXTRACTION

Reviewers with methodologic and content expertise conducted data extraction independently.

DATA SYNTHESIS

The literature search identified 6869 citations. Review of abstracts led to the retrieval of 538 full-text articles for assessment; 40 articles were selected for review. Of these, 20 (50%) articles were cohort studies and 13 (33%) articles were case series. Five articles used control groups, including three before and after case series, a case-control study, and a nonrandomized controlled trial. A total of 115 quality indicators in adult trauma care was identified, predominantly measures of hospital processes (62%) and outcomes (17%) of care. We did not identify any posthospital or secondary injury prevention quality indicators. Reliability was described for two quality indicators, content validity for 22 quality indicators, construct validity for eight quality indicators, and criterion validity for 46 quality indicators. A total of 58 quality indicators was implemented and evaluated in three studies. Eight quality indicators had supporting evidence for more than one measurement domain. A single quality indicator, peer review for preventable death, had both reliability and validity evidence.

CONCLUSIONS

Although many quality indicators are available to measure the quality of trauma care, reliability evidence, validity evidence, and description of outcomes after implementation are limited.

Preliminary evidence for leukocyte transcriptional signatures for pediatric ventilator-associated pneumonia

OBJECTIVE

Ventilator-associated pneumonia (VAP) is a significant contributor to intensive care unit (ICU) morbidity and mortality and presents a significant diagnostic challenge. Our hypothesis was that blood RNA expression profiles can be used to track the response to VAP in children, using the same methods that proved informational in adults.

DESIGN

A pilot, nonrandomized, repeated measures case-control study of changes in the abundance of total RNA in buffy coat and clinical scores for VAP.

SETTING

A large, multispecialty university-based pediatric ICU and cardiac ICU.

PATIENTS

Seven children requiring intubation and mechanical ventilation.

INTERVENTIONS

Blood samples were drawn at time of enrollment and every 48 hours for a maximum of 11 samples (21 days). Patients ranged in age from 1 to 18 months (mean 8 months). All patients survived to the end of the study. Of the 7 patients studied, 4 developed VAP.

MEASUREMENTS AND MAIN RESULTS

Statistical analysis of the Affymetrix Human Genome Focus GeneChip signal was conducted on normalized expression values of 8793 probe sets using analysis of variance (ANOVA) with a false discovery rate of 0.10. The expression patterns of 48 genes appeared to discriminate between the 2 classes of ventilated children: those with and those without pneumonia. Gene expression network analysis revealed several gene ontologies of interest, including cell proliferation, differentiation, growth, and apoptosis, as well as genes not previously implicated in sepsis.

CONCLUSIONS

These preliminary data are the first in critically ill children supporting the hypothesis that there is a detectable VAP signal in gene expression profiles. Larger studies are needed to validate these preliminary findings and test the diagnostic value of longitudinal changes in leukocyte RNA signatures.

Attenuated hypocholesterolemia following severe trauma signals risk for late ventilator-associated pneumonia, ventilator dependency, and death: a retrospective study of consecutive patients

BACKGROUND

Post-traumatic ventilator-associated pneumonia (VAP) is a substantial clinical problem that increases hospital costs and typically adds to the duration of mechanical ventilation. We evaluated the impact of VAP on ventilator days. We also assessed 48-hour total blood cholesterol (TC) and other potential risk factors for the development of VAP.

METHODS

We performed a retrospective study of consecutive trauma patients requiring emergency tracheal intubation and evaluated TC, age, gender, ethanol status, smoker status, injury mechanism, chest injury, brain injury, Injury Severity Score (ISS), shock, day-one hypoxemia, and RBC transfusion as potential risks for VAP.

RESULTS

The 152 patients had ISS 28.1, brain injury 68.4%, VAP 50.0%, ventilator days 14.3, and death 9.9%. Ventilator days were increased with late VAP (p < 0.0001). TC was 110.7 mg/dL with expected TC 197.5 mg/dL. TC was lower with chest injury, shock, and RBC transfusion but, higher with brain injury (p ≤ 0.01). TC decreased as ISS increased (p = 0.01). However, one patient subset (ISS ≥ 20-&-TC ≥ 90 mg/dL) had a relative increase in TC despite an increase in ISS. ISS ≥ 20-&-TC ≥ 90 mg/dL, but not ISS alone, was the only independent predictor of late VAP (OR 3.0; p = 0.002). ISS ≥ 20-&-TC ≥ 90 mg/dL and day-one hypoxemia were the only independent predictors for increased ventilator days (p = 0.01). ISS ≥ 20-&-TC ≥ 90 mg/dL, but not ISS alone, was the only predictor of death (OR 3.8; p = 0.03).

CONCLUSIONS

Severe traumatic injury produced substantial hypocholesterolemia that is greater with chest injury, shock, and RBC transfusion, but less with brain injury. Total blood cholesterol tended to decrease with increasing injury severity. However, attenuated hypocholesterolemia (ISS ≥ 20-&-TC ≥ 90 mg/dL) represents a unique response that can occur with critical injury. Attenuated hypocholesterolemia signals early risk for late VAP, ventilator dependency, and death.

Ventilator-associated pneumonia in trauma patients is associated with lower mortality: results from EU-VAP study

BACKGROUND

Differences in trauma patients developing ventilator-associated pneumonia (VAP) are described regarding etiology and risk factors associated. We aim to describe the differences in outcomes in trauma and nontrauma patients with VAP.

METHODS

A prospective, observational study conducted in 27 intensive care units from nine European countries. We included patients requiring invasive mechanical ventilation for >48 hours who developed VAP. Logistic regression model was used to assess the factors independently associated with mortality in trauma patients with VAP.

RESULTS

A total of 2,436 patients were evaluated; 465 developed VAP and of these 128 (27.5%) were trauma patients. Trauma patients were younger than nontrauma (45.3 ± 19.4 vs. 61.1 ± 16.7, p < 0.0001). Nontrauma had higher simplified acute physiology score II compared with trauma patients (45.5 ± 16.3 vs. 41.1 ± 15.2, p = 0.009). Most prevalent pathogens in trauma patients with early VAP were Enterobacteriaceae spp. (46.9% vs. 27.8%, p = 0.06) followed by methicillin-susceptible Staphylococcus aureus (30.6% vs. 13%, p = 0.03) and then Haemophilus influenzae (14.3% vs. 1.9%, p = 0.02), and the most prevalent pathogen in late VAP was Acinetobacter baumannii (12.2% vs. 44.4%, p < 0.0001). Mortality was higher in nontrauma patients than in trauma patients (42.6% vs. 17.2%, p < 0.001, odds ratio [OR] = 3.55, 95%CI = 2.14-5.88). A logistic regression model adjusted for sex, age, severity of illness at intensive care unit admission, and sepsis-related organ failure assessment score at the day of VAP diagnosis confirmed that trauma was associated with a lower mortality compared with nontrauma patients (odds ratio [OR] = 0.37, 95%CI = 0.21-0.65).

CONCLUSIONS

Trauma patients developing VAP had different demographic characteristics and episodes of etiology. After adjustment for potential confounders, VAP episodes in trauma patients are associated with lower mortality when compared with nontrauma patients.

Recognition and prevention of nosocomial pneumonia in the intensive care unit and infection control in mechanical ventilation

Nosocomial pneumonia (NP) is a difficult diagnosis to establish in the critically ill patient due to the presence of underlying cardiopulmonary disorders (e.g., pulmonary contusion, acute respiratory distress syndrome, atelectasis) and the nonspecific radiographic and clinical signs associated with this infection. Additionally, the classification of NP in the intensive care unit setting has become increasingly complex, as the types of patients who develop NP become more diverse. The occurrence of NP is especially problematic as it is associated with a greater risk of hospital mortality, longer lengths of stay on mechanical ventilation and in the intensive care unit, a greater need for tracheostomy, and significantly increased medical care costs. The adverse effects of NP on healthcare outcomes has increased pressure on clinicians and healthcare systems to prevent this infection, as well as other nosocomial infections that complicate the hospital course of patients with respiratory failure. This manuscript will provide a brief overview of the current approaches for the diagnosis of NP and focus on strategies for prevention. Finally, we will provide some guidance on how standardized or protocolized care of mechanically ventilated patients can reduce the occurrence of and morbidity associated with complications like NP.

The Problems Diagnosing Ventilator-Associated Pneumonia

Ventilator-associated pneumonia (VAP) is the most common healthcare-associated infection in the intensive care unit. Clinical, radiological and microbiological criteria are used to make the diagnosis, but there is no consensus definition, as no individual criterion or combination of criteria offer sufficient diagnostic accuracy to support their sole use in defining VAP. Neither invasive bronchoscopic sampling nor less invasive quantitative tracheal aspirate, conveys an advantage when making the microbiological diagnosis of VAP. Of the scoring systems and definitions presently in use, the Clinical Pulmonary Infection Score (CPIS) has been shown to be prone to inter-observer variability; the US Centers for Disease Control (CDC) National Healthcare Safety Network (NHSN) definition relies heavily on subjective clinical criteria, and the Hospitals in Europe Link for Infection Control through Surveillance (HELICS) criteria employ similarly subjective clinical criteria with five different possibilities for microbiological diagnosis. The use of these different diagnostic methods leads to marked variation in the reported incidence of VAP. Clinical practice requires an objective and transferable definition for VAP so that we can improve the reporting, monitoring and treatment of VAP.

Outbreak of Pseudomonas aeruginosa infection associated with contamination of a flexible bronchoscope

BACKGROUND

A cluster of patients with respiratory cultures positive for Pseudomonas aeruginosa with a unique antibiogram was observed during June and July 2007 at a 1,000-bed urban teaching hospital in Atlanta, Georgia. These P. aeruginosa isolates were recovered from bronchoscopically obtained specimens.

METHODS

A cross-sectional study was performed to assess whether the cluster was associated with exposure to a particular bronchoscope (B1); cultures from specimens from the bronchoscopes and the environment were obtained, and the P. aeruginosa isolate type was determined using pulsed-field gel electrophoresis (PFGE). Records of patients exposed to B1 during the cluster period were reviewed.

RESULTS

Twelve patients with a culture positive for P. aeruginosa with the unique susceptibility pattern were identified in June-July 2007. No cases were documented from March 1 through May 31, 2007. Culture specimens obtained from B1 after high-level disinfection revealed P. aeruginosa, prompting removal of B1 from service on July 23, 2007. No cases occurred after that date. Eleven (55%) of 20 patients who were exposed to B1 during the cluster period had a culture positive for P. aeruginosa, compared with 1 (2%) of 53 patients who were exposed to other bronchoscopes (P < .001). PFGE patterns for P. aeruginosa isolates obtained from case patients and from B1 were identical. An engineering evaluation of B1 documented several internal damages. Two (10.5%) of 19 patients exposed to B1 during the cluster period may have developed P. aeruginosa infection following exposure to B1.

CONCLUSIONS

An outbreak or pseudo-outbreak of P. aeruginosa infection occurred in association with use of a damaged bronchoscope. Periodic engineering maintenance may be needed to prevent bronchoscope contamination that is resistant to high-level disinfection.

The impact of hospital-acquired infection on outcome in acute pancreatitis

BACKGROUND & AIMS

Little is known regarding the impact of hospital-acquired infection (HAI) in acute pancreatitis (AP). We conducted a population-based assessment of the impact of HAI on outcome in AP.

METHODS

Patient data were obtained from the Cardinal Health Clinical Outcomes Research Database, a large population-based data set. Cases with principal diagnosis by International Classification of Diseases, ninth revision, clinical modification 577.0 (AP) between January 2004 and January 2005 were identified. These cases were linked with recently reported HAI data collected by the Pennsylvania Health Care Cost Containment Council. Identification of HAI was based on definitions set forth by the National Nosocomial Infection Surveillance System. We conducted a 5:1 multivariate propensity-matched cohort study to determine the independent contribution of HAI to in-hospital mortality, length of stay (LOS), and hospital charges.

RESULTS

From 177 participating hospitals, there were 11,046 AP cases identified. Eighty-two (0.7%) patients developed an HAI. Mortality in the overall AP population was 1.2% vs 11.4% among 405 matched non-HAI controls vs 28.4% among patients who developed HAI (chi(2) test, P < .0001). Fifteen percent of all deaths was associated with an HAI. Both average LOS and hospital charges were significantly increased among patients with HAI compared with matched non-HAI controls.

CONCLUSIONS

We determined that HAI had a major impact on mortality in AP. Patients who developed HAI also had significantly increased LOS and hospital charges. These differences were not explained by increased disease severity alone. Reducing HAI is an important step to improving outcome in AP.

Diagnosis of ventilator-associated pneumonia: a systematic review of the literature

INTRODUCTION

Early, accurate diagnosis is fundamental in the management of patients with ventilator-associated pneumonia (VAP). The aim of this qualitative review was to compare various criteria of diagnosing VAP in the intensive care unit (ICU) with a special emphasis on the value of clinical diagnosis, microbiological culture techniques, and biomarkers of host response.

METHODS

A MEDLINE search was performed using the keyword 'ventilator associated pneumonia' AND 'diagnosis'. Our search was limited to human studies published between January 1966 and June 2007. Only studies of at least 25 adult patients were included. Predefined variables were collected, including year of publication, study design (prospective/retrospective), number of patients included, and disease group.

RESULTS

Of 572 articles fulfilling the initial search criteria, 159 articles were chosen for detailed review of the full text. A total of 64 articles fulfilled the inclusion criteria and were included in our review. Clinical criteria, used in combination, may be helpful in diagnosing VAP, however, the considerable inter-observer variability and the moderate performance should be taken in account. Bacteriologic data do not increase the accuracy of diagnosis as compared to clinical diagnosis. Quantitative cultures obtained by different methods seem to be rather equivalent in diagnosing VAP. Blood cultures are relatively insensitive to diagnose pneumonia. The rapid availability of cytological data, including inflammatory cells and Gram stains, may be useful in initial therapeutic decisions in patients with suspected VAP. C-reactive protein, procalcitonin, and soluble triggering receptor expressed on myeloid cells are promising biomarkers in diagnosing VAP.

CONCLUSION

An integrated approach should be followed in diagnosing and treating patients with VAP, including early antibiotic therapy and subsequent rectification according to clinical response and results of bacteriologic cultures.

The role of lung function in brain tissue oxygenation following traumatic brain injury

Object

Previous studies have demonstrated that periods of low brain tissue oxygen tension (PbtO2) are associated with poor outcome after head trauma but have primarily focused on cerebral and hemodynamic factors as causes of low PbtO2. The purpose of this study was to investigate the influence of lung function on PbtO2 with an oxygen challenge (increase in fraction of inspired oxygen [FiO2] concentration to 1.0).

Methods

This prospective observational cohort study was performed in the neurointensive care unit of the Level 1 trauma center at San Francisco General Hospital. Thirty-seven patients with severe traumatic brain injury (TBI) undergoing brain tissue oxygen monitoring as part of regular care underwent an oxygen challenge, consisting of an increase in FiO2 concentration from baseline to 1.0 for 20 minutes. Partial pressure of arterial oxygen (PaO2), PbtO2, and the ratio of PaO2 to FiO2 (the PF ratio) were determined before and after oxygen challenge.

Results

Patients with higher PF ratios achieved greater PbtO2 during oxygen challenge than those with a low PF ratio because they achieved a higher PaO2 after an oxygen challenge. Lung function, specifically the PF ratio, is a major determinant of the maximal PbtO2 attained during an oxygen challenge.

Conclusions

Given that patients with TBI are at risk for pulmonary complications such as pneumonia, severe atelectasis, and adult respiratory distress syndrome, lung function must be considered when interpreting brain tissue oxygenation.

Article Commentary: Strategies in the Prevention and Management of Ventilator-Associated Pneumonia

Ventilator-associated pneumonia (VAP) is a leading cause of morbidity and mortality in the intensive care unit. Prevention of VAP is possible through the use of several evidence-based strategies intended to minimize intubation, the duration of mechanical ventilation, and the risk of aspiration of oropharyngeal pathogens. Current data favor the quantitative analysis of lower respiratory tract cultures for the diagnosis of VAP, accompanied by the initiation of broad-spectrum empiric antimicrobial therapy based on patient risk factors for infection with multi-drug-resistant pathogens and data from unit-specific antibiograms. Eventual choice of antibiotic and duration of therapy are selected based on culture results and patient stability, with an emphasis on minimization of unnecessary antibiotic use.

Measurement of Adult Antibacterial Drug Use in 130 US Hospitals: Comparison of Defined Daily Dose and Days of Therapy

BACKGROUND

Hospitals are advised to measure antibiotic use and monitor its relationship to resistance. The World Health Organization's recommended metric is the defined daily dose (DDD). An alternative measure is the number of days of therapy (DOT). The purpose of this study was to contrast these measures.

METHODS

We measured the use of 50 antibacterial drugs that were administered to adults who were discharged from 130 US hospitals during 1 August 2002-31 July 2003.

RESULTS

Of 1,795,504 patients, 1,074,174 received at least 1 dose of an antibacterial drug (59.8%). The mean (+/- standard deviation) of total antibacterial drug use measured by the number of DDDs per 1000 patient-days and the number of DOTs per 1000 patient-days were not significantly different (792+/-147 and 776+/-120, respectively; P=.137), although the correlation was poor (r=0.603). For some individual drugs, such as levofloxacin and linezolid, there was no significant difference between DDDs per 1000 patient-days and DOTs per 1000 patient-days, because the administered daily dosage was nearly equivalent to the DDD. When the administered dosage exceeded the DDD, such as for ampicillin-sulbactam and cefepime, estimates of use based on DDDs per 1000 patient-days significantly exceeded those based on DOTs per 1000 patient-days (P<.001). When the administered dosage was less than the DDD, such as for piperacillin-tazobactam and ceftriaxone, estimates of use based on DDDs per 1000 patient-days were significantly lower than those based on DOTs per 1000 patient-days (P<.001).

CONCLUSION

The measurement of aggregate hospital antibiotic use by DDDs per 1000 patient-days and DOTs per 1000 patient-days is discordant for many frequently used antibacterial drugs, because the administered dose is dissimilar from the DDD recommended by the World Health Organization. DDD methods are useful for benchmarking purposes but cannot be used to make inferences about the number of DOTs or relative use for many antibacterial drugs.

Advances in burn critical care

BACKGROUND

Management of burn patients requires a complex interaction of surgical, medical, critical care, and rehabilitation approaches. Severe burn patients are some of the most challenging critically ill patients who may have multiple-system organ failure with life-threatening complications.

OBJECTIVE

To review and highlight some of the recent advances in burn critical care. We focused on some of the new treatment modalities in the management of respiratory complications, advances in burn resuscitation, management of the metabolic response to burns, and recent ideas in burn immunotherapy.

DATA SOURCE

A search of the MEDLINE database and manual review of published articles and abstracts from national and international meetings. DATA SYNTHESES AND CONCLUSIONS: The respiratory management of burn patients includes strategies to minimize iatrogenic injury with low tidal volume ventilation, to improve ventilation/perfusion mismatch, and to diagnosis pneumonia. Many aspects of burn resuscitation remain controversial, and the best form of fluid resuscitation has yet to be identified. Recent research in the metabolic response to thermal injury has identified many potentially beneficial treatments. Although immunomodulation therapy is promising, currently most of these treatments are not clinically viable, and further clinical and translational research is warranted.

Diagnosis and Treatment of Ventilator-Associated Pneumonia

Ventilator-associated pneumonia (VAP) is the most common nosocomial infection in the ICU. Patients who acquire VAP have higher mortality rates and longer ICU and hospital stays. Because there are other potential causes of fever, leukocytosis, and pulmonary infiltrates, clinical diagnostic criteria are overly sensitive in the diagnosis of VAP. Employing quantitative cultures of bronchopulmonary secretions in the diagnostic algorithm leads to less antibiotic use and probably to lower mortality. With respect to microbiologic diagnosis, it is not clear that the use of a particular sampling method (bronchoscopic or nonbronchoscopic), when quantitatively cultured, is associated with better outcomes. Delayed administration of adequate antibiotic therapy is linked to an increased mortality rate. Hence, the focus of initial antibiotic therapy should be to rapidly provide antibiotic coverage for all likely pathogens and to then narrow or focus the antibiotic spectrum based on the results of quantitative cultures. Eight days of antibiotic therapy appears equivalent to 15 days of therapy except when treating nonlactose-fermenting Gram-negative organisms. In this latter situation, longer treatment durations appear to reduce the risk of recrudescence after discontinuation of antibiotic therapy. A guideline-based approach using the local hospital or ICU antibiogram can increase the likelihood that adequate initial antibiotic therapy is used and reduce the overall use of antibiotics and the associated selection pressure for multidrug-resistant organisms.