Continuous Aspiration Of Subglottic Secretions Research Articles

Evaluation of continuous aspiration of subglottic secretions in prevention of microaspiration during general anesthesia: a randomized controlled pilot study

To assess the difference between endotracheal tubes (ETT) with continuous suction of subglottic secretions (CASS) and standard ETT in preventing secretions movement from the pharynx into the trachea, past the inflated cuff during general anesthesia. This randomized, controlled trial enrolled 50 patients who underwent general anesthesia for elective abdominal surgery lasting longer than two hours. They received either ETT with CASS: Teleflex ISIS HVT (GISIS, n=17) or Mallinckrodt TaperGuard Evac (GEvac, n=17), or ETT without suction: Mallinckrodt Intermediate Hi-Lo (GStand, n=16). Methylene blue dye solution (10 mL) was delivered into the hypopharynx every 60 minutes. Subglottic secretions were continuously suctioned. Fiberoptic bronchoscopy was performed every 20 minutes and during tracheal extubation to evaluate the dye location. The groups did not differ in age, sex, body mass index, race, American Society of Anesthesiologists status, and surgery type. Dye migrated past the inflated cuff into the distal trachea in no patient with ETT with CASS and in 13% of patients with standard ETT. On tracheal extubation, dye migrated into the distal trachea more often in the GStand group (56%), compared with the GEvac (13%) and GISIS group (29%) (P=0.045). The GISIS group had 26±19 mL of secretions suctioned from above the inflated cuff, while the GEvac group had 13±10 mL (P=0.05). Compared with standard ETT, ETT with CASS efficiently removed secretions during general anesthesia, prevented secretions from migrating past the inflated cuff, and significantly reduced the amount of secretions that reached the distal airways on tracheal extubation.

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

BackgroundContinuous 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.MethodsIn 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.ResultsIn 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.ConclusionsThe 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.

Randomized Pilot Trial of Two Modified Endotracheal Tubes To Prevent Ventilator-associated Pneumonia

Ventilator-associated pneumonia (VAP) is a prevalent and costly nosocomial infection related to instrumentation of the airway with an endotracheal tube (ETT), enabling microaspiration of contaminated secretions. Modification of the ETT design to reduce microaspiration and/or biofilm formation may play an important role in VAP prevention. However, there is insufficient evidence to provide strong recommendations regarding the use of modified ETT and unaddressed safety concerns. We performed a pilot randomized controlled trial comparing two modified ETTs designed specifically to prevent VAP, with the standard ETT, to test the feasibility of and inform planning for a large, pivotal, randomized trial. This study was conducted with institutional review board approval under exception from informed consent. We randomized in a blinded fashion patients undergoing emergency endotracheal intubation both out of and in hospital to receive one of three different ETT types: (1) a polyurethane-cuffed tube (PUC-ETT), (2) a polyurethane-cuffed tube equipped with a port for continuous aspiration of subglottic secretions (PUC-CASS-ETT), or a (3) standard polyvinylchloride-cuffed tube (PVC-ETT). In addition to investigating feasibility and safety, the study coprimary end points were tracheal bacterial colonization reaching a cfu count >10(6) cfu per milliliter and the incidence of invasively diagnosed VAP. A total of 102 subjects were randomized and met the eligibility criteria. Randomization procedures performed well and integrity of blinding at randomization was maintained. The majority of intubations occurred in the hospital setting (n = 77), and the remainder occurred out of hospital (n = 25). Compared with the PVC-ETT, there were no significant differences in tracheal colonization for PUC-ETT (odds ratio [OR], 0.98; 95% confidence interval [CI], 0.31-3.09) or for PUC-CASS-ETT (OR, 1.26; 95% CI, 0.42-3.76). There were no differences in the risk of invasively diagnosed VAP (OR, 1.14; 95% CI, 0.21-6.08 for PUC-ETT; OR, 1.47; 95% CI, 0.30-7.10 for PUC-CASS-ETT), or of clinically diagnosed VAP by either clinical signs or chest radiograph criteria. We did not observe unexpected or serious adverse events related to the devices. A randomized trial of ETTs inserted during emergency intubation for the prevention of VAP is feasible and did not appear to carry heightened safety concerns. These preliminary data did not suggest different patterns of tracheal colonization or occurrence of VAP among the study groups. Clinical trial registered with www.clinicaltrials.gov (NCT01744483).

Meta analysis of continuous aspiration of subglottic secretions in preventing ventilator-associated pneumonia

Objective To assess the effectiveness of continuous aspiration of subglottic secretions (CASS)in preventing ventilator-associated pneumonia.Methods The relevant randomized controlled trials were searched in the Cochrane Library,Pubmed,CNKI,VIP and Wanfang databases.The experimental group received CASS and the control group did not(NASS group).Two reviewers selected studies according to the inclusion and exclusion criteria,the quality of studies was critically appraised and data were extracted by two reviewers independently.Meta-analysis was conducted by using RevMan 5.2.Results Sixteen randomized controlled trials met the inclusion criteria and enrolled 2 576 patients.According to the meta analysis,compared with NASS,CASS reduced the incidence of ventilator-associated pneumonia,shortened the length of stay in the intensive care unit and the duration of mechanical ventilation.There was no effect on hospital mortality.Conclusions Continuous aspiration of subglottic secretions appears effective in preventing ventilator-associated pneumonia,decreasing the duration of intensive care unit length of stay and mechanical ventilation among critically ill patients with mechanical ventilation. Key words: Continuous aspiration of subglottic secretions; Ventilator-associated pneumonia; Meta-analysis

Impact of subglottic suctioning on the incidence of pneumonia after cardiac surgery: a retrospective observational study.

Continuous aspiration of subglottic secretions (CASS) has been found to decrease the incidence of pneumonia in the general intensive care unit (ICU) population, but its benefit in cardiac surgery patients is unclear. The present study aimed to determine whether the routine use of CASS in cardiac surgical patients was associated with decreased pneumonia. A retrospective, single-center observational study. The study was conducted in a quaternary care cardiac surgery center and university research hospital. 4,880 patients undergoing cardiac surgery were studied. The control group (no CASS) received a standard endotracheal tube and underwent surgery between April 1, 2007 and March 31, 2009. The intervention group (CASS) received a subglottic suctioning endotracheal tube and underwent surgery between June 1, 2009 and May 31, 2011. The primary outcome was the development of pneumonia, and the secondary outcomes were 30-day in-hospital mortality, ventilation time, need for tracheostomy, ICU length of stay (LOS), and hospital LOS. The unadjusted incidence of pneumonia was 1.9% in the CASS group and 5.6% in the control group (p<0.0001). The CASS group also had lower 30-day in-hospital mortality (2.1% v 3.3%; p = 0.007), median ventilation time (8.42 v 7.3 hours; p<0.0001), and shorter median ICU LOS (1.77 v 1.17 days; p<0.0004) compared with the control group. Tracheostomy rates and median hospital LOS did not differ between groups. After adjusting using multivariable modeling, CASS remained an independent risk predictor for pneumonia (odds ratio [OR] 0.342, 95% confidence interval [CI] 0.239-0.490) and ICU LOS (OR 0.817, 95% CI 0.718-0.931). The universal implementation of CASS in a quaternary care cardiac surgical population was associated with a decreased incidence of pneumonia.

Use of endotracheal tubes in continuous aspiration of subglottic secretions: Knowledge and expertise of respiratory therapists and nurses

Introduction: Ventilator-associated pneumonia (VAP) is a hospital acquired nosocomial infection that is commonly found in patients receiving mechanical ventilation. Continuous aspiration of subglottic secretions (CASS) is found to lower the incidence of VAP. The aim of this study was to assess respiratory therapists and nurses’ awareness and experiences about the Endotracheal Tubes (ETT) with CASS. Methodology: This is a cross-sectional study. Purposive sampling of 51 respiratory therapists and 51 nurses who were involved in taking care of critically ill patients in adult ICUs at King Abdul-Aziz Medical City, Riyadh were used. The questionnaire was related to the knowledge and experiences of respiratory therapists and nurses about the proper use of ETT with CASS. Results: The results suggest that the respiratory therapists were more knowledgeable in the use of ETT-CASS. However, both respiratory therapists and nurses had problems related to ETT design and materials. Most of these problems were related to cuff materials and its design, suctioning system and tubes, in addition to the availability of the equipment. Conclusion: This study presents a unique contribution to knowledge about the experiences of respiratory therapists and nurses who work in KAMC about the proper use of ETT-CASS. The results of this study showed that the use of ETT-CASS is yet to be popularly recognized. Thus, it should be acclaimed by further studies and promotion through formulation of updated protocols and educational programs.

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

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

Intermittent subglottic secretion drainage may cause tracheal damage in patients with few oropharyngeal secretions

Injurious prolapse of tracheal mucosa into the suction port has been reported in up to 50% of intubated patients receiving continuous aspiration of subglottic secretions. We investigated whether similar injury could be inflicted by automated intermittent aspiration. Six consecutive patients, intubated with the Mallinckrodt TaperGuard Evac™ endotracheal tube, were studied. A flow sensor was placed between the vacuum regulating system and the mucus collector. Intermittent suctioning was performed at a pressure of -125 mmHg with a 25s interval and duration of 15s. After 24h, a CT scan of the tracheal region was performed. Excessive negative suction pressure, a fast drop in aspiration flow to zero, and important "swinging" movements of secretions in the evacuation line were observed in all patients. Oral instillation of antiseptic mouthwash restored normal aspiration flow and secretion mobility. CT imaging showed marked entrapment of tracheal mucosa into the suction port in all patients. In patients with few oropharyngeal secretions, automated intermittent subglottic aspiration may result in significant and potential harmful invagination of tracheal mucosa into the suction lumen. A critical amount of fluid must be present in the oropharynx to assure adequate and safe aspiration.

A program for sustained improvement in preventing ventilator associated pneumonia in an intensive care setting

BackgroundVentilator-associated pneumonia (VAP) is a common infection in the intensive care unit (ICU) and associated with a high mortality.MethodsA quasi-experimental study was conducted in a medical-surgical ICU. Multiple interventions to optimize VAP prevention were performed from October 2008 to December 2010. All of these processes, including the Institute for Healthcare Improvement’s (IHI) ventilator bundle plus oral decontamination with chlorhexidine and continuous aspiration of subglottic secretions (CASS), were adopted for patients undergoing mechanical ventilation.ResultsWe evaluated a total of 21,984 patient-days, and a total of 6,052 ventilator-days (ventilator utilization rate of 0.27). We found VAP rates of 1.3 and 2.0 per 1,000 ventilator days respectively in 2009 and 2010, achieving zero incidence of VAP several times during 12 months, whenever VAP bundle compliance was over 90%.ConclusionThese results suggest that it is possible to reduce VAP rates to near zero and sustain these rates, but it requires a complex process involving multiple performance measures and interventions that must be permanently monitored.

Ventilator-Associated Pneumonia: A Review

Ventilator-associated pneumonia (VAP) is the most common infection seen in intensive care units (ICUs); it accounts for one-fourth of the infections occurring in critically ill patients and is the reason for half of antibiotic prescriptions in mechanically ventilated patients. In addition to being a financial burden on ICUs, it continues to contribute significantly to the morbidity and mortality of ICU patients, with an estimated attributable mortality rate of 8% to 15%. While the pathophysiology of VAP remains relatively unchanged, diagnostic techniques and preventive measures are constantly evolving. The focus of this article is on recent trends in VAP epidemiology, modifiable risk factors, diagnostic techniques, challenges in management, and current data on the prevention of VAP. Important messages that the reader should take away include: 1) There is no gold standard for the diagnosis of VAP; whenever VAP is suspected, if feasible, a quantitative culture should be obtained by invasive or noninvasive methods (whichever is more readily available before initiation of antibiotics); 2) Suspicion based on clinical features should prompt the initiation of a broad spectrum of antibiotics depending on suspected pathogens; 3) Close attention should be paid to de-escalation of antibiotics once microbiological results become available or as the patient starts responding clinically; the ideal duration of treatment should be 8 days instead of the conventional 10 to 14 days, except in situations where Pseudomonas may be suspected or the patient's comorbidities dictate otherwise; and 4) Prevention remains the key to reducing the burden of VAP. We promote the proven preventive measures of using noninvasive ventilation when possible, semirecumbent patient positioning, continuous aspiration of subglottic secretions, and oral chlorhexidine washes along with stress ulcer prophylaxis only after careful assessment of the risks versus benefits.

Pressure transmitting device: a simple and safe method of continuous aspiration of subglottic secretions during orotracheal intubation

Many interventions are known to decrease the incidence of ventilator-associated pneumonia, which has great impact on mortality, length of stay and costs in intensive care units. One of them is the aspiration of the secretions that pool above the cuff of the endotracheal tube [1]. It is a simple device but its use is not free from complications [2], being, most of them, bleedings and obstructions due to lesions of tracheal mucosa. The maintenance of a constant suction, without wide pressure variation, is an important point to minimize these complications. The common manometers do not have enough precision to set an adequate aspiration pressure, because of its broad scale, and are not able to avoid or to limit pressure variations in case of partial occlusions, by secretion, for example, facilitating lesions occurrence. Pressure transmitting devices (Figure ​(Figure1),1), usually used for continuous aspiration of pleural drainage, have those helpful characteristics. It can be set in an adequate aspiration pressure (20 mmHg ~ 27 cmH2O) by setting the water column height. It avoids suction pressure variations since the air bubbles up on the water, balancing pressure inside the system. Figure 1 Methods Pressure transmitting devices were tested in 12 patients with subglottic aspiration on their orotracheal tubes. They were watched for complications and the findings are reported. The aspiration pressure used was set at 20 cmH2O.

Prevention of ventilator-associated pneumonia after cardiac surgery: prepare and defend!

Prevention of ventilator-associated pneumonia after cardiac surgery: prepare and defend!

Bundles to prevent ventilator-associated pneumonia: how valuable are they?

To review the value of care bundles to prevent ventilator-associated pneumonia (VAP). The Ventilator Bundle contains four components, elevation of the head of the bed to 30-45 degrees, daily 'sedation vacation' and daily assessment of readiness to extubate, peptic ulcer disease prophylaxis, and deep venous thrombosis prophylaxis, aimed to improve outcome in mechanically ventilated patients, but not all are associated with VAP prevention. Daily spontaneous awakening and breathing trials are associated with early liberation from mechanical ventilation and VAP reduction. Although a small prospective, randomized clinical study documented that the semirecumbent position was associated with a significant reduction in VAP, more recent studies have documented that the semirecumbent position is difficult to maintain in mechanically ventilated patients and may not impact VAP reduction. Prophylaxis for peptic ulcer disease and deep venous thrombosis do not directly impact VAP reduction. Other methods to reduce VAP, such as oral care and hygiene, chlorhexidine in the posterior pharynx, and specialized endotracheal tubes (continuous aspiration of subglottic secretions, silver-coated), should be considered for inclusion in a revised Ventilator Bundle more specifically aimed at VAP prevention. The Ventilator Bundle is an effective method to reduce VAP rates in ICUs. The ventilator bundle should be modified and expanded to include specific processes of care that have been definitively demonstrated to be effective in VAP reduction or a specific VAP bundle created to focus on VAP prevention.

Continuous Aspiration of Subglottic Secretions in the Prevention of Ventilator-Associated Pneumonia in the Postoperative Period of Major Heart Surgery

Continuous Aspiration of Subglottic Secretions in the Prevention of Ventilator-Associated Pneumonia in the Postoperative Period of Major Heart Surgery

Continuous Aspiration of Subglottic Secretions in the Prevention of Ventilator-Associated Pneumonia in the Postoperative Period of Major Heart Surgery

Aspiration of endotracheal secretions is a major step in the prevention of ventilator-associated pneumonia (VAP). We compared conventional and continuous aspiration of subglottic secretions (CASS) procedures in ventilated patients after major heart surgery (MHS). Randomized comparison during a 2-year period. A total of 714 patients were randomized (24 patients were excluded from the study; 359 CASS patients; 331 control subjects). The results for CASS patients and control subjects (per protocol and intention-to-treat analysis) were as follows: VAP incidence, 3.6% vs 5.3% (p = 0.2) and 3.8% vs 5.1%, respectively; incidence density, 17.9 vs 27.6 episodes per 1,000 days of mechanical ventilation (MV) [p = 0.18] and 18.9 vs 28.7 episodes per 1,000 days of MV, respectively; hospital antibiotic use in daily defined doses (DDDs), 1,213 vs 1,932 (p < 0.001) and 1,392 vs 1,932, respectively (p < 0.001). In patients who had received mechanical ventilation for > 48 h, the comparisons of CASS patients and control subjects were as follows: VAP incidence, 26.7% vs 47.5% (p = 0.04), respectively; incidence density, 31.5 vs 51.6 episodes per 1,000 days of MV, respectively (p = 0.03); median length of ICU stay, 7 vs 16.5 days (p = 0.01), respectively; hospital antibiotic use, 1,206 vs 1,877 DDD (p < 0.001), respectively; Clostridium difficile-associated diarrhea, 6.7% vs 12.5% (p = 0.3), respectively; and overall mortality rate, 44.4% vs 52.5% (p = 0.3), respectively. Reintubation increased the risk of VAP (relative risk [RR], 6.07; 95% confidence interval [CI], 2.20 to 16.60; p < 0.001), while CASS was the only significant protective factor (RR, 0.40; 95% CI, 0.16 to 0.99; p = 0.04). No complications related to CASS were observed. The cost of the CASS tube was 9 vs 1.5 euro for the conventional tube. CASS is a safe procedure that reduces the use of antimicrobial agents in the overall population and the incidence of VAP in patients who are at risk. CASS use should be encouraged, at least in patients undergoing MHS.

Effect of continuous aspiration of subglottic secretions on the prevention of ventilator-associated pneumonia in mechanically ventilated patients

The objective was to evaluate the effect of continuous aspiration of subglottic secretions (CASS) on the prevention of ventilator-associated pneumonia (VAP) in mechanically ventilated patients.

Subglottic Secretion Viscosity and Evacuation Efficiency

Ventilator-associated pneumonia (VAP) is a common nosocomial pneumonia that occurs in critically ill patients and results in mortality rates as high as 71%. Subglottic secretions (SSs) are a known risk factor. Several clinical trials have shown that continuous aspiration of subglottic secretions (CASS) reduces the risk of VAP by nearly half. Optimal suction pressure levels needed to efficiently evacuate viscous SSs are unknown. The purpose of this study was to describe SSs and the effective suction pressure (20 mmHg, 30 mmHg, 40 mmHg, and 50 mmHg) needed to maximize evacuation efficiency based on SS volume (2 ml, 4 ml, and 6 ml) and viscosity (watery, thick, and gel-like). A laboratory model was designed to replicate a human trachea. Thick secretions had the highest percentage of mean recovery representative of evacuation efficiency of SSs (mean recovery of 86%). The suction pressure of 30 mmHg had the highest overall mean of secretion recovery (83%) across all viscosity types and amounts. This study demonstrated that higher viscosity secretions were easier to evacuate than lower viscosity secretions when 30-mmHg suction pressure was applied. Management of secretion viscosity may assist in secretion removal and delay VAP development. With increased understanding of the molecular structure of SSs, there is the potential that clinicians will be able to manipulate secretion viscoelastic properties to maximize evacuation efficiency of the secretions. Further research is needed to identify safe suction pressures for optimal evacuation of SSs in human subjects.

Examination of Continuous Aspiration of Subglottic Secretions

Examination of Continuous Aspiration of Subglottic Secretions

Evaluation of Subglottic Irrigation in Conjunction with the Continuous Aspiration of Subglottic Secretions (CASS)

Evaluation of Subglottic Irrigation in Conjunction with the Continuous Aspiration of Subglottic Secretions (CASS)

Prevention and management of ventilator-associated pneumonia

Worldwide, the increasing rates of microbial resistance represent a serious public health problem. Therefore, measures to prevent ventilator-associated pneumonia gain increasing importance. Because antimicrobial treatment in the ICU is a major source of microbial resistance, prevention should be understood not only as the sum of preventive measures but also as part of any management strategy. In this year of review, several important contributions have been made to a better understanding of the relative role of preventive measures. This is particularly true of noninvasive ventilation, continuous aspiration of subglottic secretions, and closed endotracheal suctioning. Management strategies for ventilator-assisted pneumonia remain highly controversial. Despite two decades of vigorous research, there is still no evidence that invasive bronchoscopic techniques should form part of a routine approach to suspected ventilator-assisted pneumonia. Moreover, an impact in terms of important outcome variables could not be consistently demonstrated. In the authors' view, the controversy regarding the relative validity of diagnostic tools should end, and the focus should shift to strategies that define low-risk patients with suspected ventilator-assisted pneumonia who can safely be treated by short-term monotherapy. Finally, several contributions have refined the established treatment regimen. Several new drugs for the treatment of ventilator-assisted pneumonia caused by Gram-positive multiresistant pathogens have been evaluated with promising results.