Continuous aspiration of subglottic secretions in preventing ventilator-associated pneumonia

Factors affecting the number of bacteria in saliva and oral care methods for the recovery of bacteria in contaminated saliva after brushing: a randomized controlled trial

BACKGROUND

Oral care is important in preventing aspiration pneumonia in older adults. However, it is not clear what kind of oral care can reduce the number of bacteria in saliva. The purposes of this study are to clarify whether there is a relationship between plaque amounts and salivary bacterial counts, and how bacteria dispersed into the oral cavity by brushing can be reduced.

METHODS

First, saliva samples were collected from 10 healthy adult volunteers after 30 h of unbrushing and after thorough brushing, and the total bacterial count was determined by real-time PCR. Next, 40 older adults attending an outpatient dental clinic were randomly assigned into two groups: a wiping group (20 patients) and a mouthwashing group (20 patients). Saliva was collected before and after brushing, and after wiping in the wiping group and after mouthwashing in the mouthwashing group, and the total bacterial count was quantified by real-time PCR.

RESULTS

In a study of volunteers, there was no association between plaque amounts and salivary bacterial counts. In a study of older adult patients, salivary bacterial counts were significantly higher in patients with higher oral hygiene index and fewer remaining teeth. Brushing increased salivary bacterial counts. Wiping did not significantly reduce the number of bacteria, while mouthwash returned the increased number of bacteria after brushing to the pre-brushing level.

CONCLUSIONS

There is no direct relationship between the amount of plaque and the number of bacteria in saliva. Brushing disperses bacteria into the oral cavity, resulting in a marked increase in the number of bacteria in saliva. Wiping does not collect the dispersed bacteria, and it seems essential to rinse the mouth after brushing.

TRIAL REGISTRATION

UMIN000045854.

Barriers to compliance with evidence-based guidelines for ventilator-associated pneumonia among critical care nurses: A scoping review

Background: Healthcare organizations provide evidence-based guidelines designed to support nurses in preventing ventilator-associated pneumonia (VAP) in intensive care units (ICUs), but there are barriers to compliance with such guidelines. This review explicitly explored evidence of compliance barriers among critical care nurses. Methods: A systematic search was conducted in PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and EBSCO databases for relevant English-language studies published between January 2003 and June 2022, focused on barriers to nursing compliance with VAP prevention guidelines. Data was reported according to the Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMAScR) guidelines.  Results: 230 publications were screened, resulting in 53 full-text articles being retrieved after removing duplicates, of which 13 relevant to the aims of the review and meeting the inclusion criteria were included for data extraction. One was a qualitative study, while the remainder were quantitative. Simple descriptive content analysis identified the barriers to critical care nurses’ compliance with VAP prevention guidelines, and categorized them as: (1) work environment barriers (e.g., lack of equipment and supplies; lack of staff and time; lack of educational support; and ineffective supportive system); (2) nurse-related barriers (limited personal competencies); and (3) situation-related barriers (patient health, discomfort, and adverse events). Conclusions: This review revealed important evidence on barriers to VAP prevention guidelines compliance. Nurses are challenged mainly by work-environmental barriers along, with the presence of nurse and situational barriers. It is evident from the findings that further qualitative and mixed-methodology follow-up studies are recommended to further explore the issues in depth.  Healthcare leaders must be aware of these barriers and integrate work policies that assist in overcoming them, to increase compliance.

Barriers to compliance with evidence-based guidelines for ventilator-associated pneumonia among critical care nurses: A scoping review

Background: Healthcare organizations provide evidence-based guidelines designed to support nurses in preventing ventilator-associated pneumonia (VAP) in intensive care units (ICUs), but there are barriers to compliance with such guidelines. This review explicitly explored evidence of compliance barriers among critical care nurses. Methods: A systematic search was conducted in PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and EBSCO databases for relevant English-language studies published between January 2003 and June 2022, focused on barriers to nursing compliance with VAP prevention guidelines. Data was reported according to the Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMAScR) guidelines.  Results: 230 publications were screened, resulting in 53 full-text articles being retrieved after removing duplicates, of which 13 relevant to the aims of the review and meeting the inclusion criteria were included for data extraction. One was a qualitative study, while the remainder were quantitative. Simple descriptive content analysis identified the barriers to critical care nurses’ compliance with VAP prevention guidelines, and categorized them as: (1) work environment barriers (e.g., lack of equipment and supplies; lack of staff and time; lack of educational support; and ineffective supportive system); (2) nurse-related barriers (limited personal competencies); and (3) situation-related barriers (patient health, discomfort, and adverse events). Conclusions: This review revealed important evidence on barriers to VAP prevention guidelines compliance. Nurses are challenged mainly by work-environmental barriers along, with the presence of nurse and situational barriers. It is evident from the findings that further qualitative and mixed-methodology follow-up studies are recommended to further explore the issues in depth.  Healthcare leaders must be aware of these barriers and integrate work policies that assist in overcoming them, to increase compliance.

Ventilator-associated pneumonia prevention in the Intensive care unit using Postpyloric tube feeding in China (VIP study): study protocol for a randomized controlled trial

BACKGROUND

Ventilator-associated pneumonia is a challenge in critical care and is associated with high mortality and morbidity. Although some consensuses on preventing ventilator-associated pneumonia are reached, it is still somewhat controversial. Meta-analysis has shown that postpyloric tube feeding may reduce the incidences of ventilator-associated pneumonia, which still desires high-quality evidence. This trial aims to evaluate the efficacy and safety profiles of postpyloric tube feeding versus gastric tube feeding.

METHODS/DESIGN

In this multicenter, open-label, randomized controlled trial, we will recruit 924 subjects expected to receive mechanical ventilation for no less than 48 h. Subjects on mechanical ventilation will be randomized (1:1) to receive postpyloric or gastric tube feeding and routine preventive measures simultaneously. The primary outcome is the proportion of patients with at least one ventilator-associated pneumonia episode. Adverse events and serious adverse events will be observed closely.

DISCUSSION

The VIP study is a large-sample-sized, multicenter, open-label, randomized, parallel-group, controlled trial of postpyloric tube feeding in China and is well-designed based on previous studies. The results of this trial may help to provide evidence-based recommendations for the prevention of ventilator-associated pneumonia.

TRIAL REGISTRATION

Chictr.org.cn ChiCTR2100051593 . Registered on 28 September 2021.

Effect of modified care bundle for prevention of ventilator-associated pneumonia in critically-ill neurosurgical patients

Background:

Care bundles for ventilator-associated pneumonia (VAP) have been shown to minimize the rate of VAP in critically ill patients. Standard care bundles may need to be modified in resource-constrained situations. The goal of this study was to see if our modified VAP-care bundles lowered the risk of VAP in neurosurgical patients.

Methods:

A prospective cohort study was conducted in mechanically ventilated neurosurgical patients. The VAP bundle was adjusted in the cohort group by increasing the frequency of intermittent endotracheal tube cuff pressure monitoring to six times a day while reducing oral care with 0.12% chlorhexidine to three times a day. The rate of VAP was compared to the historical control group.

Results:

A total of 146 and 145 patients were enrolled in control and cohort groups, respectively. The mean age of patients was 52±16 years in both groups (P=0.803). The admission Glasgow coma scores were 7.79±2.67 and 7.80±2.77 in control and cohort group, respectively (P=0.969). VAP was found in nine patients in control group but only one patient in cohort group. The occurrence rate of VAP was significantly reduced in cohort group compared to control group (0.88/1,000 vs. 6.84/1,000 ventilator days, P=0.036).

Conclusions:

The modified VAP bundle is effective in lowering the VAP rate in critically ill neurosurgical patients. It requires low budget and manpower and can be employed in resource-constrained settings.

Ventilator-Associated Events: Epidemiology, Risk Factors, and Prevention

The Centers for Disease Control and Prevention shifted the focus of safety surveillance in mechanically ventilated patients from ventilator-associated pneumonia to ventilator-associated events in 2013 to increase the objectivity and reproducibility of surveillance and to encourage quality improvement programs to focus on preventing a broader array of complications. Ventilator-associated events are associated with a doubling of the risk of dying. Prospective studies have found that minimizing sedation, increasing spontaneous awakening and breathing trials, and conservative fluid management can decrease event rates and the duration of ventilation. Multifaceted interventions to enhance these practices can decrease ventilator-associated event rates.

Pseudomonas aeruginosa biofilm formation on endotracheal tubes requires multiple two-component systems

Introduction. Indwelling medical devices such as endotracheal tubes (ETTs), urinary catheters, vascular access devices, tracheostomies and feeding tubes are often associated with hospital-acquired infections. Bacterial biofilm formed on the ETTs in intubated patients is a significant risk factor associated with ventilator-associated pneumonia. Pseudomonas aeruginosa is one of the four frequently encountered bacteria responsible for causing pneumonia, and the biofilm formation on ETTs. However, understanding of biofilm formation on ETT and interventions to prevent biofilm remains lagging. The ability to sense and adapt to external cues contributes to their success. Thus, the biofilm formation is likely to be influenced by the two-component systems (TCSs) that are composed of a membrane-associated sensor kinase and an intracellular response regulator.Aim. This study aims to establish an in vitro method to analyse the P. aeruginosa biofilm formation on ETTs, and identify the TCSs that contribute to this process.Methodology. In total, 112 P. aeruginosa PA14 TCS mutants were tested for their ability to form biofilm on ETTs, their effect on quorum sensing (QS) and motility.Results. Out of 112 TCS mutants studied, 56 had altered biofilm biomass on ETTs. Although the biofilm formation on ETTs is QS-dependent, none of the 56 loci controlled quorum signal. Of these, 18 novel TCSs specific to ETT biofilm were identified, namely, AauS, AgtS, ColR, CopS, CprR, NasT, KdpD, ParS, PmrB, PprA, PvrS, RcsC, PA14_11120, PA14_32580, PA14_45880, PA14_49420, PA14_52240, PA14_70790. The set of 56 included the GacS network, TCS proteins involved in fimbriae synthesis, TCS proteins involved in antimicrobial peptide resistance, and surface-sensing. Additionally, several of the TCS-encoding genes involved in biofilm formation on ETTs were found to be linked to flagellum-dependent swimming motility.Conclusions. Our study established an in vitro method for studying P. aeruginosa biofilm formation on the ETT surfaces. We also identified novel ETT-specific TCSs that could serve as targets to prevent biofilm formation on indwelling devices frequently used in clinical settings.

Subglottic secretion drainage for preventing ventilator-associated pneumonia: an overview of systematic reviews and an updated meta-analysis

Although several guidelines recommend subglottic secretion drainage as a strategy for prevention of ventilator-associated pneumonia (VAP), its use is not widespread. With the aim to assess the effectiveness of subglottic secretion drainage for preventing VAP and to improve other outcomes such as mortality, duration of mechanical ventilation and length of stay in the intensive care unit (ICU) or hospital, an electronic search of the Cochrane Library, MEDLINE, Web of Science and Embase was undertaken. Nine systematic reviews with meta-analysis (in the overview of reviews) and 20 randomised controlled trials (in the updated meta-analysis) were included.

In the overview of reviews, all systematic reviews with meta-analysis included found a positive effect of subglottic secretion drainage in the reduction of incidence of VAP. In the updated meta-analysis, subglottic secretion drainage significantly reduced VAP incidence (risk ratio (RR) 0.56, 95% CI 0.48–0.63; I²=0%, p=0.841) and mortality (RR 0.88, 95% CI 0.80–0.97; I²=0%, p=0.888).

This is the first study that has found a decrease of mortality associated with the use of subglottic secretion drainage. In addition, subglottic secretion drainage is an effective measure to reduce VAP incidence, despite not improving the duration of mechanical ventilation and ICU and/or hospital length of stay.

Subglottic secretion drainage is an effective measure to reduce mortality and VAP incidence, despite not improving the duration of mechanical ventilation or length of stay in ICU and/or hospital.http://bit.ly/2PeJLR1

Airway Devices in Ventilator-Associated Pneumonia Pathogenesis and Prevention

Airway devices play a major role in the pathogenesis of microaspiration of contaminated oropharyngeal and gastric secretions, tracheobronchial colonization, and ventilator-associated pneumonia (VAP) occurrence. Subglottic secretion drainage is an effective measure for VAP prevention, and no routine change of ventilator circuit. Continuous control of cuff pressure, silver-coated tracheal tubes, low-volume low-pressure tracheal tubes, and the mucus shaver are promising devices that should be further evaluated by large randomized controlled trials. Polyurethane-cuffed, conical-shaped cuff, and closed tracheal suctioning system are not effective and should not be used for VAP prevention.

Ventilator-associated pneumonia: The central role of transcolonization

Ventilator-associated pneumonia remain frequent and serious diseases since they are associated with considerable crude mortality. Pathophysiology is centered on modifications of regional bacterial flora, especially tracheobronchial tree and oropharyngeal sphere. Bacterial migration from an anatomical area to another seems to be the main explanation of these alterations which are called "transcolonization". The association of transcolonization and lack of tightness of the endotracheal tube cuff provides a direct pathway for bacteria from the upper to the subglottic airways, eventually leading to ventilator-associated pneumonia. Although modification of bacterial flora has been largely studied, the mechanism which underlays the ability of the implantation, growing and interactions with the local microbiome that leads to the observed transcolonization remains to be more clearly deciphered. The aim of our review is to emphasize the cornerstone importance of the "transcolonization" as a nosological entity playing a central role in ventilator-associated pneumonia.

Devising negative pressure within intercuff space reduces microaspiration

Background

Microaspiration past the tracheal tube cuffs causes ventilator-associated pneumonia. The objective of the current study was to evaluate whether creating negative pressure between the tracheal double cuffs could block the fluid passage past the tracheal tube cuffs.

Methods

A new negative pressure system was devised between the double cuffs through a suction hole in the intercuff space. Blue-dyed water was instilled above the cuff at negative suction pressures of − 54, − 68, − 82, − 95, − 109, − 122, and − 136 cmH₂O, and the volume leaked was measured in an underlying water trap after 10 min. Leakage tests were also performed during positive pressure ventilation, and using higher-viscosity materials. The actual negative pressures delivered at the hole of double cuffs were obtained by placing microcatheter tip between the intercuff space and the artificial trachea.

Results

No leakage occurred past the double cuff at − 136 cmH₂O suction pressure at all tracheal tube cuff pressures. The volume leaked decreased significantly as suction pressure increased. When connected to a mechanical ventilator, no leakage was found at − 54 cmH₂suction pressure. Volume of the higher-viscosity materials (dynamic viscosity of 63–108 cP <cP> and 370–430 cP) leaked was small compared to that of normal saline (0.9–1.1 cP). The pressures measured in the intercuff space corresponded to 3.8–5.9% of those applied.

Conclusions

A new prototype double cuff with negative pressure in the intercuff space completely prevented water leakage. The negative pressure transmitted to the tracheal inner wall was a small percentage of that applied.

Subglottic secretion drainage for ventilator-associated pneumonia prevention: an underused efficient measure

Subglottic secretion drainage (SSD) is one of the recommended strategies to prevent ventilator-associated pneumonia (VAP) with a high level of evidence, especially regarding early-onset pneumonia. All meta-analysis found that the use of SSD reduces VAP occurrence with a relative risk (RR) reduction of 45%. In some of them, SSD reduces the duration of mechanical ventilation (MV) but without beneficial effect on intensive care unit (ICU) or hospital mortality. In spite of the edited recommendations, SSD has not been widely implemented in ICUs and remains underused. Several factors could account for this: doubts on the innocuousness of using SSD, persisting reservations on the SSD effect on other outcomes than VAP, a high variability in the volume of secretions suctioned between patients and, for each individual patient, during the period of MV and the initial increased expense of the specific endotracheal tubes (ETs) allowing SSD which limits the availability of these devices.

Influence of subglottic secretion drainage on the microorganisms of ventilator associated pneumonia: A meta-analysis for subglottic secretion drainage

BACKGROUND

The influence of the subglottic secretion drainage (SSD) on the microorganisms of ventilator associated pneumonia (VAP) is still unclear.A meta-analysis focusing on the influence of the SSD on the microorganisms of VAP.

METHODS

A comprehensive search was conducted through the online studies of PubMed, Embase, Cochrane Library, Google scholar, CNKI (China National Knowledge Infrastructure), and VIPI (Database for Chinese Technical Periodicals) using specific search terms.Included studies were randomized controlled trials (RCTs) that compare the microorganisms of VAP between SSD and standard endotracheal tube care in mechanically ventilated adults.

RESULTS

Nine RCTs were eligible. There was no significant difference in the rate of VAP caused by nonfermentative bacteria and enterobacteria between SSD group and control group (OR = 0.73, 95%CI, 0.53-1.01; P = .06). The episodes of VAP caused by Gram-positive cocci and Haemophilus influenzae organisms were lower in the SSD group (OR = 0.29, 95%CI, 0.18-0.48; P<0.00001). Less mean volume of SSD daily was observed in VAP group (OR = -16.97, 95%CI, -29.87-4.08; P = .010).

CONCLUSION

We found SSD to be associated with significant decreases in VAP caused by Gram-positive cocci and H influenzae organisms but no significant differences in VAP caused by nonfermentative bacteria and enterobacteria. Less mean volume of SSD daily was observed in VAP group.

What is new in the prevention of nosocomial pneumonia in the ICU?

PURPOSE OF REVIEW

To summarize and contextualize recent evidence on preventing ventilator-associated pneumonia (VAP).

RECENT FINDINGS

Many centers continue to report dramatic decreases in VAP rates after implementing ventilator bundles. Interpreting these reports is complicated, however, by the subjectivity and lack of specificity of VAP definitions. More objective data suggest VAP rates may not have meaningfully changed over the past decade. If so, this compels us to re-examine and revise the prevention bundles we have been using to prevent VAP. New analyses suggest that most hospitals' ventilator bundles include a mix of helpful and potentially harmful elements. Spontaneous awakening trials, spontaneous breathing trials, head-of-bed elevation, and thromboprophylaxis appear beneficial. Oral chlorhexidine and stress ulcer prophylaxis may be harmful. Subglottic secretion drainage, probiotics, and novel endotracheal cuff designs do not clearly improve objective outcomes. Selective digestive decontamination by contrast appears to lower VAP and mortality rates. Effective implementation is as important as choosing the right bundle components. Best practices include engaging and educating staff, creating structures that facilitate bundle adherence, and providing regular feedback on process measure performance and outcome rates.

SUMMARY

VAP rates may still be elevated despite multiple reports to the contrary. Recent evidence suggests new ways to optimize the selection of ventilator bundle components and their implementation.

Effect of Nasogastric Tube on Aspiration Risk: Results from 147 Patients with Dysphagia and Literature Review

Nasogastric tube (NGT) is a common feeding strategy for patients at risk of endotracheal aspiration with an oral diet. With NGT feeding, however, swallowing of small amounts saliva cannot be avoided. We investigated whether the aspiration rate when swallowing 1 mL of fluid increased in patients using an NGT in different dysphagia severities. One hundred forty-seven patients who had been receiving NGT feeding underwent a videofluoroscopic swallowing study (VFSS). During VFSS, subjects were offered 1 mL of fluid twice: initially, with the tube inserted (NGT-in) and, subsequently, with the tube removed (NGT-out). Aspiration depth was determined using the 8-point Penetration-Aspiration Scale (PAS) (0 points, no aspiration/penetration; 8 points, aspiration passing the vocal cords with no ejection efforts). PAS-diff was computed (PAS_NGT-in - PAS_NGT-out), and a positive PAS-diff (PAS-diff > 0) meant increased aspiration depth in the presence of NGT. After VFSS, diet recommendations were made according to dysphagia severity assessment: non-oral feeding (n = 59), diet modification (n = 74), and diet as tolerated (n = 13). Cognitive level (mini-mental state examination, MMSE) and general functional level (Modified Barthel Index, MBI) were compared between the PAS-diff > 0 and PAS-diff ≤ 0 groups. Aspiration severity did not significantly change after NGT removal (PAS_NGT-in, 2.45 ± 2.40; PAS_NGT-out, 2.57 ± 2.58; P = .50). Regardless of recommended diet, PAS-diff values were not significantly different (P = .49). MMSE and MBI were not significantly different (P = .23 and .94) between subjects with PAS-diff > 0 (n = 25) and PAS-diff ≤ 0 (n = 121). In conclusion, the risk of aspirating a small amount of fluid was not significantly different before and after NGT removal, regardless of swallowing function, cognitive level, or general functional level.

Efficacy of continuous versus intermittent subglottic secretion drainage in preventing ventilator-associated pneumonia in patients requiring mechanical ventilation: A single-center randomized controlled trial

Objective

Aspiration of subglottic secretion is a widely used intervention to prevent ventilator-associated pneumonia (VAP). This study aimed to compare the efficacy of continuous and intermittent subglottic secretion drainage (SSD) in preventing VAP.

Methods

A single-center randomized controlled trial was conducted on adult postoperative patients who were expected to undergo mechanical ventilation for more than 48 hours. Primary outcome measure was incidence of VAP and secondary outcome measures were length of mechanical ventilation and intensive-care unit (ICU) stay.

Results

Fifty-nine patients received continuous SSD, while 60 patients received intermittent SSD. Of these 119 patients, 88 (74%) were excluded and 15 and 16 patients were allocated to receive continuous and intermittent SSD, respectively. VAP was detected in 4 (26.7%) and 7 (43.8%) patients in the continuous and intermittent groups, respectively, (p=0.320). The length of mechanical ventilation was significantly shorter (p=0.034) in the continuous group (99.5±47.1 h) than in the intermittent group (159.9±94.5 h). The length of ICU stay was also shorter (p=0.0097) in the continuous group (6.3±2.1 days) than the intermittent group (9.8±4.8 days).

Conclusions

Although continuous SSD did not reduce the incidence of VAP, it reduced the length of mechanical ventilation and ICU stay when compared to intermittent SSD.

Incidence of airway complications in patients using endotracheal tubes with continuous aspiration of subglottic secretions

BACKGROUND

Continuous aspiration of subglottic secretions is effective in preventing ventilator-associated pneumonia, but it involves a risk of mucosal damage. The main objective of our study was to determine the incidence of airway complications related to continuous aspiration of subglottic secretions.

METHODS

In consecutive adult patients with continuous aspiration of subglottic secretions, we prospectively recorded clinical airway complications during the period after extubation. A multidetector computed tomography of the neck was performed during the period of 5 days following extubation to classify subglottic and tracheal lesions as mucosal thickening, cartilage thickening or deep ulceration.

RESULTS

In the 86 patients included in the study, 6 (6.9%) had transient dyspnea, 7 (8.1%) had upper airway obstruction and 18 (20.9%) had dysphonia at extubation. Univariate analysis identified more attempts required for intubation (2.3 ± 1.1 vs. 1.2 ± 0.5; p = 0.001), difficult intubation (71.4 vs. 10.1%, p = 0.001) and Cormack score III-IV (71.4 vs. 8.8%; p < 0.001) as risk factors for having an upper airway obstruction at extubation. The incidence of failed extubation among patients after planned extubation was 18.9% and 11 patients (12.7%) required tracheostomy. A multidetector computed tomography was performed in 37 patients following extubation, and injuries were observed in 9 patients (24.3%) and classified as tracheal injuries in 2 patients (1 cartilage thickening and 1 mild stenosis with cartilage thickening) and as subglottic mucosal thickenings in 7 patients.

CONCLUSIONS

The incidence of upper airway obstruction after extubation in patients with continuous aspiration of subglottic secretions was 8.1%, and the injuries observed by computed tomography were not severe and located mostly in subglottic space.

Ventilator-Associated Events and Their Prevention

The Centers for Disease Control and Prevention shifted the focus of safety surveillance in mechanically ventilated patients from ventilator-associated pneumonia to ventilator-associated events (VAEs) in 2013. The shift was designed to increase the objectivity and reproducibility of surveillance and to encourage quality-improvement programs to tackle a broader array of complications in mechanically ventilated patients. Prospective intervention studies have found that minimizing sedation, increasing the use of spontaneous awakening and breathing trials, and conservative fluid management can lower VAE rates and decrease duration of mechanical ventilation. Additional strategies to prevent VAEs include early mobility programs, low tidal volume ventilation, and restrictive transfusion thresholds.

Assessment of the effectiveness of a ventilator associated pneumonia prevention bundle that contains endotracheal tube with subglottic drainage and cuff pressure monitorization

The effectiveness of prevention bundles on the occurrence and mortality of ventilator associated pneumonia (VAP) was evaluated in many studies. However, the effectiveness of endotracheal tube with subglottic secretion drainage (ETT-SD) and cuff pressure monitorization in VAP bundles have not been adequately assessed. In this study, we aimed to evaluate the effectiveness of VAP bundle containing ETT-SD and cuff pressure monitorization. This was a prospective, controlled study that was carried out between March 2011 and April 2012 including intubated patients. The study was conducted at the Anesthesiology Intensive Care Unit 1 and 2 (10 beds each) in a 898-bed university hospital. Occurrence of VAP and compliance with the parameters of the VAP prevention bundles were assessed daily. Patients intubated with the standard endotracheal tube were recruited as controls, mainly in the first six months of the study as ETT-SD and cuff pressure monometer had not yet been implemented. In the second term, patients intubated with ETT-SD were included as cases. Occurrence of VAP, mortality, and compliance with VAP prevention bundles were monitored. A total of 133 patients, 37 cases and 96 controls were recruited. VAP incidence declined from 40.82 to 22.16 per 1000 ventilator days among controls and cases, respectively (p<005). On average, VAP occurred 17.33±21.09 days in the case group and 10.43±7.83 days in the control group (p=0.04). However, mortality of cases and controls at the 14th and 30th days was not different. VAP prevention bundles including the utilization of ETT-SD, monitoring cuff pressure, and oral care with chlorhexidine were efficient in reducing the rate of VAP.

Aspiration and the Risk of Ventilator-Associated Pneumonia

Ventilator-associated pneumonia (VAP) is a major concern in the intensive care unit. It is estimated that the risk of developing VAP may be as high as 1% per ventilated day, and the attributable mortality approaches 50% in some series. A growing body of evidence implicates the role of microaspiration of contaminated oropharyngeal and perhaps gastroesophageal secretions into the airways as an integral step in the pathogenesis of VAP. In patients who have been intubated and mechanically ventilated for >72 hours, the majority of VAP is caused by enteric gram-negative organisms, presumably of gastrointestinal origin. As a result, strategies designed to minimize the risk of these contaminated secretions into the normally sterile airways are of paramount importance in terms of VAP prevention. This review highlights the important etiological role of the gut in the development of VAP and also discusses the evidence behind interventions that may modulate the risk of both aspiration and subsequent VAP.

Infection in the Immobile Host: A Practical Review for the Intensive Care Physician

Immobility in the critically ill patient is a significant risk factor for infection, independent of the patient's underlying critical illness. Specific causes of infection related to immobility in the intensive care setting are explored. The pathogenesis, treatment, complications, and prevention of pressure ulcers, pneumonia, and urinary tract infections in the immobile patient are emphasized. Featured topics include the differentiation of colonization versus infection in pressure ulcers and the urinary tract, the significance and optimal treatment of positive fungal cultures, as well as a rational clinical approach to the immobile patient with a fever and no obvious source of infection. The clinical relevance of anaerobic infections in this population is emphasized because it influences empiric antibiotic therapy and differential diagnosis.

Subglottic secretion suction for preventing ventilator-associated pneumonia: an updated meta-analysis and trial sequential analysis

Background

Potential benefits of subglottic secretion suction for preventing ventilator-associated pneumonia (VAP) are not fully understood.

Methods

We searched Cochrane Central, PubMed, and EMBASE up to March 2016 to identify randomized controlled trials (RCTs) that compared subglottic secretion suction versus non-subglottic secretion suction in adults with mechanical ventilation. Meta-analysis was conducted using Revman 5.3, trial sequential analysis (TSA) 0.9 and STATA 12.0. The primary outcome was incidence of VAP. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was used to evaluate the level of evidence.

Results

Twenty RCTs (N = 3544) were identified. Subglottic secretion suction was associated with reduction of VAP incidence in four high quality trials (relative risk (RR) 0.54, 95 % confidence interval (CI) 0.40–0.74; p < 0.00001) and in all trials (RR = 0.55, 95 % CI 0.48– 0.63; p < 0.00001). Sensitivity analyses did not show differences in the pooled results. Additionally, the results of the above-mentioned analyses were confirmed in TSA. GRADE level was high. Subglottic secretion suction significantly reduced incidence of early onset VAP, gram-positive or gram-negative bacteria causing VAP, and duration of mechanical ventilation. It delayed the time-to-onset of VAP. However, no significant differences in late onset VAP, intensive care unit (ICU) mortality, hospital mortality, or ICU length of stay were found.

Conclusions

Subglottic secretion suction decreased VAP incidence and duration of mechanical ventilation and delayed VAP onset. However, subglottic secretion suction did not reduce mortality and length of ICU stay. Subglottic secretion suction is recommended for preventing VAP and for reducing ventilation length, especially in the population at high risk of early onset VAP.

Trial registration

A protocol of this meta-analysis has been registered on PROSPERO (registration number: CRD42015015715); registered on 5 January 2015.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-016-1527-7) contains supplementary material, which is available to authorized users.

Efficacy of Hi-Lo Evac Endotracheal Tube in Prevention of Ventilator-Associated Pneumonia in Mechanically Ventilated Poisoned Patients

Background. Ventilator-associated pneumonia (VAP) is the most common health care-associated infection. To prevent this complication, aspiration of subglottic secretions using Hi-Lo Evac endotracheal tube (Evac ETT) is a recommended intervention. However, there are some reports on Evac ETT dysfunction. We aimed to compare the incidence of VAP (per ventilated patients) in severely ill poisoned patients who were intubated using Evac ETT versus conventional endotracheal tubes (C-ETT) in our toxicology ICU. Materials and Methods. In this clinical randomized trial, 91 eligible patients with an expected duration of mechanical ventilation of more than 48 hours were recruited and randomly assigned into two groups: (1) subglottic secretion drainage (SSD) group who were intubated by Evac ETT (n = 43) and (2) control group who were intubated by C-ETT (n = 48). Results. Of the 91 eligible patients, 56 (61.5%) were male. VAP was detected in 24 of 43 (55.8%) patients in the case group and 23 of 48 (47.9%) patients in the control group (P = 0.45). The most frequently isolated microorganisms were S. aureus (54.10%) and Acinetobacter spp. (19.68%). The incidence of VAP and ICU length of stay were not significantly different between the two groups, but duration of intubation was statistically different and was longer in the SSD group. Mortality rate was less in SSD group but without a significant difference (P = 0.68). Conclusion. The SSD procedure was performed intermittently with one-hour intervals using 10 mL syringe. Subglottic secretion drainage does not significantly reduce the incidence of VAP in patients receiving MV. This strategy appears to be ineffective in preventing VAP among ICU patients.

Ventilator-Associated Pneumonia: A Review

Ventilator-associated pneumonia is the most frequent intensive care unit (ICU)-related infection in patients requiring mechanical ventilation. In contrast to other ICU-related infections, which have a low mortality rate, the mortality rate for ventilator-associated pneumonia ranges from 20% to 50%. These clinically significant infections prolong duration of mechanical ventilation and ICU length of stay, underscoring the financial burden these infections impose on the health care system. The causes of ventilator-associated pneumonia are varied and differ across different patient populations and different types of ICUs. This varied presentation underscores the need for the intensivist treating the patient with ventilator-associated pneumonia to have a clear knowledge of the ambient microbiologic flora in their ICU. Prevention of this disease process is of paramount importance and requires a multifaceted approach. Once a diagnosis of ventilator-associated pneumonia is suspected, early broad-spectrum antibiotic administration decreases morbidity and mortality and should be based on knowledge of the sensitivities of common infecting organisms in the ICU. De-escalation of therapy, once final culture results are available, is necessary to minimize development of resistant pathogens. Duration of therapy should be based on the patient’s clinical response, and every effort should be made to minimize duration of therapy, thus further minimizing the risk of resistance.

Inapparent Outbreaks of Ventilator-Associated Pneumonia An Ecologic Analysis of Prevention and Cohort Studies

Objective:

To compare ventilator-associated pneumonia (VAP) rates and patterns of isolates across studies of antibiotic and non-antibiotic methods for preventing VAP.

Design:

With the use of 42 cohort study groups as the reference standard, the prevalence of VAP was modeled in two linear regressions: one with the control groups and the other with the intervention groups of 96 VAP prevention studies. The proportion of patients admitted with trauma and the VAP diagnostic criteria were used as ecologic correlates. Also, the patterns of pathogenic isolates were available for 117 groups.

Results:

In the first regression model, the VAP rates for the control groups of antibiotic-based prevention studies were at least 18 (CI95, 12 to 24) per 100 patients higher than those in the cohort study groups (P< .001). By contrast, comparisons of cohort study groups with all other control and intervention groups in the first and second regression models yielded differences that were less than 6 per 100 and not significant (P> .05). For control groups with VAP rates greater than 35%, the patterns of VAP isolates, such as the proportion ofStaphylococcus aureus,more closely resembled those in the corresponding intervention groups than in the cohort groups.

Conclusions:

The rates of VAP in the control groups of the antibiotic prevention studies were significantly higher than expected and the patterns of pathogenic isolates were unusual. These observations suggest that inapparent outbreaks of VAP occurred in these studies. The possibility remains that antibiotic-based VAP prevention presents a major cross-infection hazard.

The effect of tooth brushing, irrigation, and topical tetracycline administration on the reduction of oral bacteria in mechanically ventilated patients: a preliminary study

Background

One of the main causes of ventilator-associated pneumonia (VAP) is thought to be aspiration of oropharyngeal fluid containing pathogenic microorganisms. The aim of this study was to examine the effects of various oral care methods on the reduction of oral bacteria during intubation.

Methods

First, the effect of mechanical oral cleaning was investigated. The bacterial count on the tongue and in the oropharyngeal fluid was measured after tooth brushing, irrigation, and three hours after irrigation in mechanically ventilated patients at the intensive care unit (ICU).

Next, the efficacy of topical administration of tetracycline and povidone iodine on the inhibition of bacterial growth on the tongue and in the oropharyngeal fluid was examined in oral cancer patients during neck dissection.

Results

The number of bacteria in the oropharyngeal fluid was approximately 10⁵–10⁶ cfu/mL before surgery, but increased to 10⁸ cfu/mL after intubation. Oral care with tooth brushing and mucosal cleaning did not reduce oral bacteria, while irrigation of the oral cavity and oropharynx significantly decreased it to a level of 10⁵ cfu/mL (p < 0.001). However, oral bacteria increased again to almost 10⁸ cfu/mL within three hours of irrigation.

Oral bacteria did not decrease by topical povidone iodine application. In contrast, 30 min after topical administration of tetracycline, the number of oral bacteria decreased to 10⁵ cfu/mL, and remained under 10⁶ cfu/mL throughout the entire experimental period of 150 min.

Conclusions

While the present studies are only preliminary, these results indicate that irrigation of the oral cavity and oropharynx followed by topical antibiotic administration may reduce oral bacteria in mechanically ventilated patients.

Trial registration

UMIN000018318, 1 August 2015.

"Post intubation Laryngeal injuries in a pediatric intensive care unit of tertiary hospital in India: A Fibreoptic endoscopic study"

STUDY OBJECTIVES

To identify acute laryngeal injuries among pediatric patients intubated for more than 48hours, and to correlate these injuries with clinical variables.

SETTING

Pediatric Intensive Care Unit (PICU) of a tertiary level hospital in India.

PATIENTS AND METHODS

Prospective, observational study. Thirty-four children meeting the inclusion and exclusion criteria were recruited into the study after obtaining informed consent from the parents. A bedside, flexible, fiberoptic laryngoscopy was done within the first 24hours of extubation. Laryngeal injuries were documented and graded. Individual types of laryngeal injuries were correlated to the duration of intubation, size of the tube, the experience of the intubator and the patient's demographics. A repeat endoscopy was done in the outpatient department, 3-4 weeks after extubation, and findings noted.

RESULTS

97% had acute laryngeal injury, of which 88% were significant. Erythema was the most common form of injury. Duration of intubation, with a mean of 4.5 days, showed a trend towards significance (p=0.06) for association with subglottic narrowing. Laryngeal injuries were similar with both cuffed and uncuffed tubes. Age of the subject, size of the tube and skill level of the intubator did not correlate with the laryngeal injuries. 18% required intervention for post-extubation laryngeal lesions. Three (10%) children had post-extubation stridor, and of these, two needed surgical intervention (6%).

CONCLUSION

Post-extubation laryngeal injuries are not uncommon. Fiberoptic endoscopy is an inexpensive and cost-effective tool for bedside evaluation of post-intubation status in pediatric larynx. Early diagnosis of post-intubation laryngeal injuries in children can prevent long term sequelae. Hence, post-extubation fiberoptic laryngoscopy should be done routinely in pediatric population.

Efficacy of intermittent sub-glottic suctioning in prevention of ventilator-associated pneumonia- A preliminary study of 100 patients

Background and Aims:

Oropharyngeal colonisation followed by aspiration of contaminated secretions is the major cause for ventilator-associated pneumonia (VAP). Pooled secretions present in the sub-glottic area above inflated endotracheal tube cuff may be aspirated into the lower airways. It was hypothesised that intermittent suctioning of sub-glottic secretions would prevent VAP.

Methods:

Group I (n = 50) patients were intubated with HiLo Evac™ endotracheal (ET) tube with facility for sub-glottic suctioning, and Group II (n = 50) patients were intubated with HiLo Contour™ ET tube without such facility. In the Group I, sub-glottic suctioning was performed every 2 h. Incidence of VAP, mean ventilator days, Intensive Care Unit (ICU) stay and mortality were compared. Qualitative variables were reported as percentages and were compared by Chi-square test or unpaired two-tailed, Fisher's exact test, as appropriate, to analyse the significance of difference between the two groups.

Results:

The two groups were similar with respect to demographic characteristics. VAP was seen in 6% of patients in Group I and 22% of patients in Group II (P = 0.021). Both early- and late-onset VAPs were significantly reduced in Group I. Both ventilator days (8.0 vs. 6.45; P = 0.001) and ICU stay (8.33 vs. 6.33; P = 0.001) on the day of onset of VAP were significantly more in the Group I. Total ventilator days were significantly less (6.52 vs. 8.32; P = 0.006) with lower incidence of mortality (36% vs. 48%; P = 0.224) in the Group I.

Conclusion:

Intermittent sub-glottic suctioning reduces the incidence of VAP including late-onset VAP.

Preventive Effect on Post-Operative Pneumonia of Oral Health Care among Patients Who Undergo Esophageal Resection: A Multi-Center Retrospective Study

BACKGROUND

Post-operative pneumonia is a frequent and possibly fatal complication of esophagectomy and is likely caused by aspiration of oropharyngeal fluid that contains pathogenic micro-organisms. We conducted a multi-center retrospective study to investigate the preventive effect of oral health care on post-operative pneumonia among patients with esophageal cancer who underwent esophagectomy.

METHODS

A total of 280 patients underwent esophagectomy at three university hospitals. These patients were divided retrospectively into those who received pre-operative oral care from dentists and dental hygienists (oral care group; n = 173) and those who did not receive such care (control group; n = 107). We evaluated the correlations between the occurrence of post-operative pneumonia and 18 predictive variables (patient factors, tumor factors, treatment factors, and pre-operative oral care) using the χ(2) test and logistic regression analysis. The differences of mean hospital days and mortality rate in both groups were analyzed by the Student t-test.

RESULTS

Age, post-operative dysphagia, and absence of pre-operative oral care were correlated significantly with post-operative pneumonia in the univariable analysis. Multivariable analysis revealed that diabetes mellitus, post-operative dysphagia, and the absence of pre-operative oral care were independent risk factors for post-operative pneumonia. The mean hospital stay and mortality rate did not differ between the oral care and control groups.

CONCLUSION

Pre-operative oral care may be an effective and easy method to prevent post-operative pneumonia in patients who are undergoing esophagectomy.

Tapered-cuff Endotracheal Tube Does Not Prevent Early Postoperative Pneumonia Compared with Spherical-cuff Endotracheal Tube after Major Vascular Surgery

Background

Patients undergoing major vascular surgery often develop postoperative pneumonia that impacts their outcomes. Conflicting data exist concerning the potential benefit of tapered-shaped cuffs on tracheal sealing. The primary objective of this study was to assess the efficiency of a polyvinyl chloride tapered-cuff endotracheal tube at reducing the postoperative pneumonia rate after major vascular surgery. Secondary objectives were to determine its impact on microaspiration, ventilator-associated pneumonia rate, and inner cuff pressure.

Methods

This prospective randomized controlled study included 109 patients who were randomly assigned to receive either spherical- (standard cuff) or taper-shaped (tapered cuff) endotracheal tubes inserted after anesthesia induction and then admitted to the intensive care unit after major vascular surgery. Cuff pressure was continuously recorded over 5 h. Pepsin and α-amylase concentrations in tracheal aspirates were quantified on postoperative days 1 and 2. The primary outcome was the early postoperative pneumonia frequency.

Results

Comparing the tapered-cuff with standard-cuff group, respectively, postoperative pneumonia rates were comparable (42 vs. 44%, P = 0.87) and the percentage (interquartile range) of cuff-pressure time with overinflation was significantly higher (16.1% [1.5 to 50] vs. 0.6% [0 to 8.3], P = 0.01), with a 2.5-fold higher coefficient of variation (20.2 [10.6 to 29.4] vs. 7.6 [6.2 to 10.2], P &lt; 0.001). Although microaspiration frequencies were high, they did not differ between groups.

Conclusion

For major vascular surgery patients, polyvinyl chloride tapered-cuff endotracheal tubes with intermittent cuff-pressure control did not lower the early postoperative pneumonia frequency and did not prevent microaspiration.

Initial empirical antibacterial therapy of ventilator-associated pneumonia

Ventilator-associated pneumonia (VAP) is the most frequently occurring nosocomial infection, accounting for considerable morbidity and mortality. Diagnosis can be difficult, creating important therapeutic challenges for intensivists. Early therapy is important in maximizing outcomes, but inappropriate antibacterial treatment has its own risks. A balance needs to be struck between the necessary therapeutic benefits and the negative effects (selection of resistant pathogens, costs, and adverse effects) of antibacterials. Several studies have indicated, in various groups of critically ill patients including those with VAP, that starting treatment with an ineffective antibacterial can increase hospital and intensive care unit length of stay and mortality. When the responsible microorganisms cannot be defined, it may be better to start treatment with a broad-spectrum antibacterial regimen, taking into account individual patient factors and local bacteriology patterns, including antibacterial resistance. As soon as the nature of the pathogen has been defined, the antibacterial agent(s) should be modified accordingly, with the primary aim to reduce the antibacterial spectrum. The optimal duration of therapy is controversial and probably best tailored to the individual patient depending on clinical response and resolution of the factors used to diagnose VAP in that patient. Consultation with an infectious disease specialist may facilitate these therapeutic decisions. With the high morbidity and mortality associated with VAP, prevention is an important issue. General measures include adequate hand hygiene. Physicians must be aware of the risk factors for VAP and of accepted and effective strategies of prevention.

Use of the Blom Tracheotomy Tube with Suction Inner Cannula to Decontaminate Microorganisms from the Subglottic Space. A Proof of Concept

RATIONALE

Preventing pulmonary complications during mechanical ventilation via tracheotomy is a high priority.

OBJECTIVES

To investigate if the Blom tracheotomy tube with suction-above-the-cuff inner cannula reduced the quantity of normal flora and pathogens in supra- versus subglottic spaces.

METHODS

We enrolled 20 consecutive medical ICU adults requiring tracheostomy for mechanical ventilation in this proof-of-concept, prospective, single-center study. All participants received a Blom tracheotomy tube with suction-above-the-cuff inner cannula to decontaminate microorganisms from the supra- and subglottic spaces. Supra- and subglottic sputum samples were obtained for microbiologic analysis while an endotracheal tube was in place before tracheotomy and once per week for up to 4 weeks of mechanical ventilation after tracheotomy.

MEASUREMENTS AND MAIN RESULTS

Demographics, duration of endotracheal tube intubation, and duration of mechanical ventilation post-tracheotomy were recorded. There was a significant reduction for supraglottic (2.86 ± 1.11 [mean ± SD]) versus subglottic suction samples (2.48 ± 1.07) (paired t test, P = 0.048; Wilcoxon test, P = 0.045) when all data pairs for normal flora and pathogens were combined across times. There was a significant reduction of normal flora pooled across times in 19 data pairs for supraglottic (3.00 ± 1.05) versus subglottic suction samples (2.00 ± 0.94) (paired t test, P = 0.0004; Wilcoxon test, P = 0.0007). There was no significant reduction of pathogens pooled across times in 25 data pairs for supraglottic (2.76 ± 1.16) versus subglottic suction samples (2.84 ± 1.03) (paired t test, P = 0.75; Wilcoxon test, P = 0.83).

CONCLUSIONS

Proof-of-concept was confirmed. The Blom tracheotomy tube with disposable suction-above-the-cuff inner cannula decontaminated microorganisms from the subglottic space when normal flora and pathogens were combined. Future research should investigate if decreased quantity of normal flora and pathogens in the subglottic space reduces the incidence of ventilator-associated pulmonary complications in critically ill patients requiring ongoing mechanical ventilation via tracheotomy.

Impact of supra-cuff suction on ventilator-associated pneumonia prevention

Critically ill patients are intubated or tracheostomized because, in most cases, these individuals require invasive mechanical ventilation. The cannulae that are used include the cuff, which can act as a reservoir for oropharyngeal secretions, predisposing to ventilator-associated pneumonia. Studies have revealed that the suction of subglottic secretions through the dorsal suction lumen above the endotracheal tube cuff delays the onset and reduces the incidence of ventilator-associated pneumonia. The aim of this review is to assess published studies regarding the significance of using suction with a supra-cuff device for the prevention of ventilator-associated pneumonia in critically ill patients treated with orotracheal intubation or tracheostomy. Therefore, by searching national and international databases, a literature review was undertaken of studies published between the years 1986 and 2011. Few results were found relating the suction of subglottic secretions to decreased duration of mechanical ventilation and length of stay in the intensive care unit. The suction of subglottic secretions is ineffective in decreasing mortality but is effective in reducing the incidence of early-onset ventilator-associated pneumonia and hospital costs. Techniques involving continuous suction of subglottic secretions may be particularly efficient in removing secretions; however, intermittent suction appears to be the least harmful method. In conclusion, cannulae with a supra-cuff suction device enable the aspiration of subglottic secretions, providing benefits to critically ill patients by reducing the incidence of ventilator-associated pneumonia and, consequently, hospital costs - with no large-scale adverse effects.

Handcrafted cuff manometers do not accurately measure endotracheal tube cuff pressure

OBJECTIVE

To test the agreement between two handcrafted devices and a cuff-specific manometer.

METHODS

The agreement between two handcrafted devices adapted to measure tracheal tube cuff pressure and a cuff-specific manometer was tested on 79 subjects. The cuff pressure was measured with a commercial manometer and with two handcrafted devices (HD) assembled with aneroid sphygmomanometers (HD1 and HD2). The data were compared using Wilcoxon and Spearman tests, the intraclass correlation coefficient (ICC) and limit-of-agreement analysis.

RESULTS

Cuff pressures assessed with handcrafted devices were significantly different from commercial device measurements (pressures were higher when measured with HD1 and lower with HD2). The ICCs between the commercial device and HD1 and HD2 were excellent (ICC = 0.8 p < 0.001) and good (ICC = 0.66, p < 0.001), respectively. However, the Bland- Altman plots showed wide limits of agreement between HD1 and HD2 and the commercial device.

CONCLUSION

The handcrafted manometers do not provide accurate cuff pressure measurements when compared to a cuff-specific device and should not be used to replace the commercial cuff manometers in mechanically ventilated patients.

Nosocomial Infection Caused by Antibiotic-Resistant Organisms in the Intensive-Care Unit

Resistance to antimicrobial agents is an evolving process, driven by the selective pressure of heavy antibiotic use in individuals living in close proximity to others. The intensive care unit (ICU), crowded with debilitated patients who are receiving broad-spectrum antibiotics and being cared for by busy physicians, nurses, and technicians, serves as an ideal environment for the emergence of antibiotic resistance. Problem pathogens presently include multiply resistant gram-negative bacilli, methicillin-resistantStaphylococcus aureus, and the recently emerged vancomycin-resistant enterococci. The prevention of antimicrobial resistance in ICUs should focus on recognition via routine unit-based sur veillance, improved compliance with handwashing and barrier precautions, and antibiotic-use policies tailored to individual units within hospitals.

Infection control in the intensive care unit

It is critical for health care personnel to recognize and appreciate the detrimental impact of intensive care unit (ICU)-acquired infections. The economic, clinical, and social expenses to patients and hospitals are overwhelming. To limit the incidence of ICU-acquired infections, aggressive infection control measures must be implemented and enforced. Researchers and national committees have developed and continue to develop evidence-based guidelines to control ICU infections. A multifaceted approach, including infection prevention committees, antimicrobial stewardship programs, daily reassessments-intervention bundles, identifying and minimizing risk factors, and continuing staff education programs, is essential. Infection control in the ICU is an evolving area of critical care research.

Infection control in the intensive care unit

Nosocomial infections are common in many hospital departments, but particularly so on the intensive care unit, where they affect some 20 to 30% of patients. While early diagnosis and appropriate treatment are, of course, important, perhaps the greatest challenge is in the application of techniques to limit the development of such infections. This review will briefly discuss some of the background pathophysiology and epidemiology of nosocomial infection, and then focus on general and infection-specific preventative strategies individually and as part of broader infection-control programs with infection surveillance.

The impact of a ventilator bundle on preventing ventilator-associated pneumonia: a multicenter study

BACKGROUND

For prevention of ventilator-associated pneumonia (VAP), a bundle approach was applied to patients receiving mechanical ventilation in intensive care units. The incidence of VAP and the preventive efficacy of the VAP bundle were investigated.

METHODS

A quasi-experimental study was conducted in adult intensive care units of 6 university hospitals with similar VAP rates. We implemented the VAP bundle between March 2011 and June 2011, then compared the rate of VAP after implementation of the VAP bundle with the rate in the previous 8 months. Our ventilator bundle included head of bed elevation, peptic ulcer disease prophylaxis, deep venous thrombosis prophylaxis, and oral decontamination with chlorhexidine 0.12%. Continuous aspiration of subglottic secretions was an option.

RESULTS

Implementation of the VAP bundle reduced the VAP rate from a mean of 4.08 cases per 1,000 ventilator-days to 1.16 cases per 1,000 ventilator-days. The incidence density ratio (rate) was 0.28 (95% confidence interval, 0.275-0.292).

CONCLUSIONS

Implementing the appropriate VAP bundle significantly decreased the incidence of VAP in patients with mechanical ventilation.

Frequency of hypoxic events in patients on a mechanical ventilator

Background:

Mechanical ventilation is an important tool in the management of respiratory failure in the critically ill patient. Although mechanical ventilation can be a life-saving intervention, it is also known to carry several side-effects and risks. Adequate oxygenation is one of the primary goals of mechanical ventilation. However, while on mechanical ventilation, patients frequently experience hypoxic events resulting from various causes, which need to be properly evaluated and treated.

Materials and Methods:

Data were obtained by prospectively reviewing all intensive care admissions during the period from March 2009 to March 2010 at a 651-bed urban medical center. Patients who developed hypoxemia (oxygen saturation ≤88% and a PaO₂≤60 torrs) while on mechanical ventilation were investigated for the cause of hypoxic event.

Results:

During the study period, 955 patients required mechanical ventilation from which 79 developed acute hypoxia. The causes of acute hypoxia in decreasing order of occurrences were pulmonary edema, atelectasis, pneumothorax, pneumonia, ARDS, endotracheal tube malfunction, airway bleeding, and pulmonary embolism.

Conclusions:

Appropriate evaluation of all hypoxic events must begin at the bedside. A step-by-step approach must include a thorough physical examination. Evaluation of the endotracheal tube can immediately reveal dislodgement, bleeding, and secretions. Correlation of physical examination findings with those on chest radiograph is essential. Each hypoxic event requires a different intervention depending on its etiology. Instead of simply increasing the fraction of oxygen in the inspired air to overcome hypoxia, a concerted effort in appropriate problem solving can reduce the likelihood of an incorrect diagnosis and management response.

Device-Related Infections in Critically Ill Patients. Part II: Prevention of Ventilator-Associated Pneumonia and Urinary Tract Infections

Device utilization in critically ill patients is responsible for a high risk of complications such as catheter-related bloodstream infections (CRBSI), ventilator-associated pneumonia (VAP) and urinary tract infections (UTI). In this article we will review the current status of data regarding the prevention of VAP and UTI. The results of the more recent (5 years) randomized controlled trials are reviewed and discussed. General recommendations include staff education and use of a surveillance program with a restrictive antibiotic policy. Adequate time must be allowed for hand washing and barrier precautions must always be used during device manipulation. Specific measures for VAP prevention are: 1) use of multi-use, closed-system suction catheters; 2) no routine change of the breathing circuit; 3) lubrication of the cuff of the endotracheal tube (ET) with a water-soluble gel; 4) maintenance of patient in semi-recumbent position to improve chest physiotherapy in intubated patients. Specific measures for UTI prevention include: 1) use of a catheter-valve instead of a standard drainage system; 2) use of a silver-alloy, hydro gel-coated latex urinary catheter instead of uncoated catheters. Biofilm represents a new variable: the capacity of bacteria to organize a biofilm on a device surface can explain the difficulty in preventing and eradicating an infection in a critically ill patient. More clinical trials are needed to verify the efficacy of prevention measures of ICU infections.