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American Journal of Critical Care. 2009;18: 133-143 doi:10.4037/ajcc2009441
Copyright © 2009 by the American Association of Critical-Care Nurses.
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Assessment of Endotracheal Cuff Pressure by Continuous Monitoring: A Pilot Study

By Mary Lou Sole, RN, PhD, CCNS, Daleen Aragon Penoyer, RN, PhD, CCRN, XioaGang Su, PhD, Edgar Jimenez, MD, Samar J. Kalita, PhD, Elizabeth Poalillo, MSN, ARNP, Jacqueline F. Byers, RN, PhD, CNAA, CPHQ, Melody Bennett, RN, MN, CCRN and Jeffery E. Ludy, EdD, RRT. Mary Lou Sole and Jacqueline F. Byers are professors, College of Nursing, XioaGang Su is an associate professor, Department of Statistics and Actuarial Science, Samar J. Kalita is an assistant professor, Department of Mechanical, Materials and Aerospace Engineering, and Jeffery E. Ludy is the director, Cardiopulmonary Science Program, at the University of Central Florida, Orlando, Florida. Daleen Aragon Penoyer is the director, Advanced Practice Nursing and Research, Edgar Jimenez is medical director, Medical Intensive Care Unit, and assistant director, Internal Medicine Residency Program, and Elizabeth Poalillo is nursing operations manager at Orlando Regional Medical Center, Orlando, Florida. Melody Bennett is project director and adjunct faculty, College of Nursing, University of Central Florida, and a staff nurse at Orlando Regional Medical Center.

Corresponding author: Mary Lou Sole, RN, PhD, CCNS, FAAN, University of Central Florida, PO Box 162210, Orlando, FL 32816-2210 (e-mail: msole{at}mail.ucf.edu).


   Abstract
Top
 Abstract
Background
 Method
 Results
 Discussion
 Summary
 References
 
Background Endotracheal tube cuff pressure must be maintained within a narrow therapeutic range to prevent complications. Cuff pressure is measured and adjusted intermittently.

Objectives To assess the accuracy and feasibility of continuous monitoring of cuff pressure, describe changes in cuff pressure over time, and identify clinical factors that influence cuff pressure.

Methods In a pilot study, data were collected for a mean of 9.3 hours on 10 patients who were orally intubated and receiving mechanical ventilation. Sixty percent of the patients were white, mean age was 55 years, and mean intubation time was 2.8 days. The initial cuff pressure was adjusted to a minimum of 20 cm H2O. The pilot balloon of the endotracheal tube was connected to a transducer and a pressure monitor. Cuff pressure was recorded every 0.008 seconds during a typical 12-hour shift and was reduced to 1-minute means. Patient care activities and interventions were recorded on a personal digital assistant.

Results Values obtained with the cufflator-manometer and the transducer were congruent. Only 54% of cuff pressure measurements were within the recommended range of 20 to 30 cm H2O. The cuff pressure was high in 16% of measurements and low in 30%. No statistically significant changes over time were noted. Endotracheal suctioning, coughing, and positioning affected cuff pressure.

Conclusions Continuous monitoring of cuff pressure is feasible, accurate, and safe. Cuff pressures vary widely among patients.

Many critically ill patients receive mechanical ventilation as a part of their treatment. These patients require an artificial airway, most often an endotracheal tube. The tube is usually inserted through the mouth (oral intubation), and its distal tip rests above the carina. The tube has a high volume, low-pressure cuff at the distal end that is inflated. The pressure in the cuff must be maintained within a therapeutic range that is high enough to ensure delivery of mechanical ventilation and prevent marked aspiration and low enough to ensure perfusion to the tracheal capillaries.1 The cuff pressure is routinely measured and monitored every 8 to 12 hours by respiratory therapists or nurses.2–4

Little research has been done on management of endotracheal tube cuff pressure since the development of the high-volume, low-pressure cuffs in the 1970s. Several aspects are unknown, including the best way to measure and maintain cuff pressure and clinical factors that influence cuff pressure. Knowledge of these aspects can assist in designing interventions to optimize management of endotracheal tube cuffs and prevent complications associated with overinflation and underinflation of the cuffs. The purpose of this pilot study was to assess the accuracy and feasibility of continuous monitoring of endotracheal tube cuff pressure in critically ill patients, describe changes in endotracheal tube cuff pressure over time, and identify clinical factors that influence cuff pressure.


The best way to measure and maintain endotracheal tube cuff pressure is unknown.

 


   Background
Top
 Abstract
 Background
Method
 Results
 Discussion
 Summary
 References
 
Importance of Cuff Pressure Management
Endotracheal intubation and mechanical ventilation are essential, life-saving treatments for many critically ill patients. Optimal values for cuff pressure of endotracheal tubes are not known, and recommended cuff pressures vary from 20 to 30 cm H2O.5–9

Overinflation of the cuff can be a problem.10–18 Pressures greater than 40 cm H2O have been reported in 91% of postoperative patients after nitrous oxide anesthesia and in 45% of patients receiving other anesthetics.18 High pressures also have been reported when endotracheal tube cuff pressures are estimated rather than directly measured.19,20 Investigators15,17,18 in the United Kingdom, Brazil, and Poland reported high endotracheal tube cuff pressures in 55% to 62% of critically ill patients; however, measurement of cuff pressure was not a routine practice. Complications of overinflation of the cuff include nerve palsy,21 tracheoesophageal fistula,22 tracheal wall damage,23 subglottic scarring or stenosis,24,25 and hoarseness.26,27 Management of endotracheal tube cuff pressure based on routine cuff pressure monitoring has resulted in fewer reported complications associated with overinflation.

Underinflation of the endotracheal tube cuff is associated with inadequate delivery of prescribed tidal volume and aspiration of secretions.6,18,23,28–36 Dullenkopf et al37 reported that a pressure of 19.1 cm H2O was required for an adequate seal of an endotracheal tube cuff. After a study of 83 patients who were intubated with an endotracheal tube that provided continuous aspiration of subglottic secretions, Rello et al6 recommended a minimum pressure of 20 cm H2O. When the cuff pressure was maintained at less than 20 cm H2O, the risk for ventilator-associated pneumonia (VAP) was 4 times higher than when pressure was maintained at higher values.6 However, Valencia et al38 compared outcomes between use of a device to automatically control cuff pressure to 20 cm H2O and use of intermittent monitoring. Endotracheal tube cuff pressure was maintained with the automatic device, but no differences were noted in VAP rates, early vs late onset of VAP, or mortality. An editorial39 accompanying the article by Valencia et al noted that 20 cm H2O may not be high enough to seal the airway and prevent silent aspiration.

Cuff Pressure Management
Three techniques are used to inflate and maintain endotracheal tube cuff pressures: minimal leak technique, minimal occlusive volume, and minimal pressure. The minimal leak technique is the most common method reported for maintaining the endotracheal tube cuff in critically ill patients.3,4 With this technique, air is slowly injected into the cuff until the air leak stops. A small amount of air is released to allow a slight air leak at peak inflation pressure. Because the leak occurs during positive pressure, it is proposed that secretions are mobilized upward, reducing the likelihood of aspiration.8 With the minimal occlusive volume technique, the cuff is slowly inflated until no leak is audible during a positive-pressure breath. This technique may be more effective than the minimal leak technique in reducing silent aspiration.40 Some institutions specify a minimal level for cuff pressure (eg, 20 cm H2O); the pressure is checked periodically, and the cuff is inflated to the recommended level.3

No standards exist for frequency and method of monitoring cuff pressure. Most US institutions have policies for endotracheal tube (and cuff pressure) management by respiratory therapists. Nurses assume a greater responsibility for cuff pressure management in other countries. The most common frequency for measuring cuff pressure is every 8 to 12 hours.2–4,41 Cuff pressure is also measured when clinical findings, such as an audible air leak or a ventilator alarm indicating a low exhaled tidal volume, indicate a decrease in pressure.41 In anesthesia and emergency department settings, practitioners often estimate cuff pressure by palpating the pilot balloon on the endotracheal tube. However, estimation techniques can be inaccurate, with less than one-third of the pressures within a desired therapeutic range.10,19,20,42

Devices to measure endotracheal tube cuff pressure are often imprecise and vary by user. In an in vitro study, Blanch43 compared measurements of 20, 40, and 60 cm H2O determined by using a calibration analyzer with 4 different cuff inflator devices. He found that bias and precision varied among the devices, and none accurately measured cuff pressure. Variation among users with the cufflator has also been reported.44


Recommendations for maintaining cuff pressure vary from 20 to 30 cm H2O.

 

Continuous monitoring of endotracheal tube cuff pressure in the operative setting has been described and is an alternative to intermittent monitoring techniques.45,46 Procedures for continuous cuff pressure monitoring have been tested and developed for research applications.47

Factors Affecting Cuff Pressure
Several factors that affect cuff pressure have been reported, but most of the studies were limited by small sample sizes, were case reports, or had other methodological issues. The design of the cuff is one factor that must be considered. Folds and wrinkles may develop in the cuff, allowing secretions to leak to the lower airway.48 In a European study,49 researchers detected leakage around the cuffs of several endotracheal tubes, at pressures ranging from 10 to 60 cm H2O. Cuff pressure can also decrease over time. Statistically significant decreases in cuff pressure from 21 cm H2O to 17 to 18 cm H2O were detected within 4 to 7 hours after adjustments in pressure.50,51 A limitation of these studies is that pressure was measured at isolated times with a manometer device. Patient movement, positioning, and other factors may affect cuff pressure.28 Increases in cuff pressure can occur when patients are moved to a sitting position and with the head flexed.51,52 Cuff pressure can decrease with head extension52 and neuromuscular blockade.53

Although some recommend that cuff pressure be maintained at a minimal level, the minimal leak technique is more commonly used.5–7 Cuff pressure is measured every 8 to 12 hours2–4; more frequent monitoring may be needed, because decreases in cuff pressure have been associated with time, measurement, and patient-related factors.6,44,50,51 Continuous monitoring of cuff pressure has not been studied in the critical care unit and may be a useful clinical and research tool for optimizing airway management. This study was undertaken to generate knowledge to assist in identifying interventions to optimize management of cuff pressures.


No standard exists for frequency and method of cuff pressure monitoring.

 


   Method
Top
 Abstract
 Background
 Method
Results
 Discussion
 Summary
 References
 
A single-group, repeated-measures design was used for the study. Table 1Go gives operational definitions of the variables. The institutional review boards at the University of Central Florida, Orlando, Florida, and Orlando Health approved the study. Informed consent was obtained from surrogates of those critically ill patients who met eligibility criteria. If a patient was alert and responsive at the time of data collection, consent to participate in the study was also obtained from the patient.


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  		Table 1 Study variables

 
The study was conducted at Orlando Regional Medical Center, a tertiary care facility in Central Florida. Patients managed by the medical critical care intensivist team were eligible for enrollment. Most patients were admitted to a 24-bed intensive care unit that provides care for medical, surgical, and neuroscience patients. Two patients were managed in the coronary care unit.

Sample
The study sample consisted of critically ill patients who required intubation and mechanical ventilation. Because this investigation was a pilot study, a sample size of 10 patients was chosen to address the research aims. Patients were included in the study if they were 18 years or older, intubated with an oral endotracheal tube, and receiving mechanical ventilation. Surrogates providing consent had the ability to read or understand English. Patients were excluded from the study if they had a tracheostomy, were on respiratory isolation, required high-frequency oscillatory ventilation, or were positioned prone as part of their treatment.

Data Collection
Demographic data were collected from each patient’s medical record. Intermittent measurement of endotracheal tube cuff pressure was obtained with a calibrated Posey Cufflator Manometer (Posey Co, Arcadia, California). The device measures pressures from 0 to 120 cm H2O with a specified accuracy of ±2 cm H2O.54

Continuous endotracheal tube cuff pressure was recorded by connecting the pilot balloon of the endotracheal tube to a 3-way stopcock with a 15-cm (6-in) extension (MX43660, Medex, Inc, Dublin, Ohio) and transducer (Transpac, Medex Inc). The transducer was connected to an Intellivue24 cardiac monitor with a pressure module (Philips, Andover, Massachusetts). All connections were taped, and the device was labeled "for Respiratory use only." The transducer was zeroed, and the mean pressure was recorded in millimeters of mercury.47 The Philips pressure module measures pressure within a range of –40 to 360 mm Hg. The reported accuracy excluding the transducer is ±1%. The accuracy of the zero adjustment is ±1 mm Hg. Pressure data were downloaded to a laptop computer with Dataplore (ixellence GmbH, Wildau, Germany) data logging interface/software. Data were recorded every .008 seconds and were reduced to 1-minute means. Data were converted from millimeters of mercury to centimeters of water for final analysis. In a laboratory comparison of intermittent cuff pressure readings with continuous monitoring, bias was 0.5 cm H2O between intermittent and continuous measures, an acceptable congruence of measures.44

Observational data on patient care activities and behaviors was recorded on a handheld personal digital assistant by using the commercially available software program Spectator GO! (Biobserve GmbH, Bonn, Germany). The program allows for real-time data acquisition to record observations.55 Start times for a variety of activities were recorded and were downloaded to the study data files in a spreadsheet format. Table 2Go lists activities that were monitored.


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  		Table 2 Activities proposed for monitoring

 
Procedures
The principal investigators and the study project director (M.B.) collected all data. Interrater reliability was established for recording demographic data, cuff pressure measurements, and observational data.

The clocks on all recording devices (cardiac monitor, laptop, personal digital assistant) were synchronized. The initial endotracheal tube cuff pressure was measured with the manometer device and was adjusted to a minimal level of 20 cm H2O. The starting pressure was higher than 20 cm H2O in several patients whose pressure was monitored and adjusted by the respiratory therapist immediately before data collection. Continuous monitoring of cuff pressure was initiated, and data were collected during the 7 AM to 7 PM shift. Because cuff pressure is measured at the beginning of each shift, the goal was to gather data in the 12-hour interim. Staff members and researchers were blinded to the continuous measurements of cuff pressure. Patient care activities and behaviors were recorded on the personal digital assistant. As a safety precaution and the standard of care, the endotracheal tube cuff was to be inflated if clinical signs and symptoms indicated a cuff leak. At the end of data collection, the transducer was detached, and the endotracheal tube cuff pressure was adjusted to a minimum pressure of 20 cm H2O with the cufflator manometer as needed.


   Results
Top
 Abstract
 Background
 Method
 Results
Discussion
 Summary
 References
 
Characteristics of the Sample
The study sample consisted of 5 men and 5 women who were monitored for 3.8 to 11.8 hours (mean, 9.3 hours). Duration of data collection was shortest for 3 patients because of extubation (n = 2) and change to an oscillator ventilator (n = 1). The patients were 28 to 75 years old (mean, 54.8; SD, 17.3) and were intubated from 1 to 7 days (mean, 2.8; SD, 2.0). Of the 10 patients, 6 were white non-Hispanic, and 4 were members of ethnic or racial minorities.

Accuracy and Feasibility
To assess accuracy of continuous monitoring with standard measurements obtained with the cufflator manometer, a Bland-Altman test was done for baseline values obtained by both methods. The bias between the values obtained via the cufflator and the transducer was –0.2 cm H2O (SD, 1.0), indicating congruence between baseline values obtained with the cufflator-manometer and the values obtained with the pressure transducer. Continuous monitoring was feasible under the immediate and constant supervision of the researchers. No adverse effects occurred during data collection, and no clinical indications of an endotracheal tube cuff leak were noted.


Cuff pressure increased during endotracheal tube suctioning, coughing, and patient-ventilator dyssynchrony.

 

Cuff Pressure
Cuff pressure data are shown in Table 3Go and smoothed plots are shown in Figure 1Go. Mean cuff pressure was 17.7 to 37.4 cm H2O. The mean of all measurements of cuff pressure was 24.6 cm H2O (SD, 4.1) and the median was 23.4 cm H2O. The percentage of time the cuff pressure was in the range of 20 to 30 cm H2O varied from 13% to 89% of the measurements, and much intrapatient variability was evident. A total of 4 patients (patients 1, 3, 6, and 9) had no episodes of pressure lower than 20 cm H2O, but they experienced intermittent pressure greater than 30 cm H2O more often than the other patients did. Most cuff pressure values were less than 20 cm H2O for 3 patients (patients 2, 5, and 10), and nearly half of the measurements less than 20 cm H2O were for 1 patient (patient 7).


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  		Table 3 Cuff pressure data

 

Figure 1
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  		Figure 1 Cuff pressure data for all 10 patients together. The B-spline method57 was used to produce the smooth curves.

 

Thirty percent of pressure measurements were less than 20 cm H2O.

 

Although the sample size was small, 5 variables related to the framework were tested via stepwise multiple regression (backward method) to identify factors, if any, that were predictive of the percentage of time the pressure was high or low. This method is useful for exploratory analysis.56 Variables entered into the analyses included position of the endotracheal tube (centimeter mark on the tube) at the lip line, duration of intubation, mean elevation of the head of the bed, baseline Sedation-Agitation Score, and Glasgow Coma Scale (GCS) score. The regression model that predicted the percentage of time pressure was high (adjusted R2 = 0.65) included GCS score (P = .006) and elevation of the head of the bed (P = .02). The regression model that predicted the percentage of time pressure was low (adjusted R2 = 0.77) included position of the endotracheal tube at the lip line (P = .02), GCS score (P = .06), elevation of the head of the bed (P = .06), and duration of intubation (P = .08).

Changes in Cuff Pressure Over Time
A heuristic approach based on simple linear regression was used to study the overall pattern in cuff pressure over time. Figure 1Go shows the smoothed plots of data for all patients. A slope estimate was computed for each patient by linearly relating cuff pressure to time. This estimate resulted in 5 positive slope estimates mixed with 5 negative ones.57 A negative slope implies an overall decreasing pattern in cuff pressure over time. A binomial test indicated no statistically significant changes in cuff pressure over time (P = .38). Nevertheless, plots of 3 patients (patients 2, 7, and 10) showed a trend to decrease over time.

Activity
Changes in endotracheal tube cuff pressure occurred with selected clinical activities. Cuff pressure increased for brief periods during endotracheal suctioning, coughing, and patient-ventilator dyssynchrony. The highest pressure recorded was 56 cm H2O. Most changes were transient, lasting 5 minutes or less. During endotracheal tube suctioning, the increase in cuff pressure ranged from 14 to 20 cm H2O. Changes in pressure also occurred with patient positioning, such as turning, and use of continuous lateral rotation therapy. In some instances, positioning resulted in an increase in pressure; in others, it caused a decrease. Less variation in endotracheal tube cuff pressure occurred after administration of sedatives and in patients with the lowest CGS scores. The standard deviation of the mean cuff pressure (variability measure) was 2.6 cm H2O for the 3 patients with a CGS score of 3 compared with 4.7 cm H2O for the 7 patients with GCS scores from 6 to 10. No changes in pressure were noted with oral care, including toothbrushing, swabbing, or oral suctioning. Recording head and neck flexion and extension was difficult because of the multiple position changes and patients’ movements; therefore, no data related to these variables were analyzed. Because the number of therapies observed was small, a detailed analysis of the effect of medications for sedation, anxiolysis, and paralysis was not done. Selected observations are shown in Figures 2Go, 3Go, and 4Go.


Figure 2
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  		Figure 2 At the start of the study, patient 1 had increases in pressure; she was alert, attempting to talk, and anxious. She was medicated with propofol at 8 AM. A fentanyl infusion was turned off at 8:15 AM, and the propofol was discontinued at 9:55 AM. The spike in cuff pressure at 9 AM is associated with endotracheal suctioning. At approximately 9:15 AM, a spike in pressure of unknown origin was noted; it was 1 hour after the fentanyl infusion was discontinued. The patient had a history of asthma; bronchoconstriction may be another cause of the sustained high pressure. Pressures decreased at 9:55 AM, when a trial of continuous positive airway pressure was begun.

 

Figure 3
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  		Figure 3 Patient 9 was sedated and showed very little variation in cuff pressure. A spike in cuff pressure was noted at 9:10 AM during endotracheal suctioning. A large increase in pressure was noted at 10:40 AM during an extensive procedure to change a dressing. Note the cyclical pattern throughout the tracing, especially from 9:40 AM to 10:40 AM.The patient was on a bed with continuous lateral rotation applied in 15-min intervals; the cuff pressure appears to vary with cyclical rotation of the patient.

 

Figure 4
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  		Figure 4 Patient 2 showed variation in endotracheal tube cuff pressure throughout data collection. The patient was recovering from surgery for a cerebral aneurysm and was being weaned off of sedative medications to promote extubation. He moved often and made many attempts to communicate with nurses and family members. He also required frequent suctioning of oral and endotracheal tube secretions.

 

   Discussion
Top
 Abstract
 Background
 Method
 Results
 Discussion
Summary
 References
 
Considerable variability in cuff pressure was noted in this study. Intermittent measurements of pressure that are part of routine practice provide only a snapshot in time and do not reflect the many factors that influence cuff pressure. The cuff pressures reported for 60% of the patients were within the recommended range at the beginning and ending of the study, but many patients had a cuff pressure that was higher or lower than recommended for a high percentage of time during the data collection period. Intermittent monitoring of pressure may give a false sense of security that the pressure is within a therapeutic range.

A total of 30% of the pressure measurements were less than 20 cm H2O. This percentage is lower than the 45% reported by Valencia et al38; however, their measurements were taken intermittently, a difference that makes comparison between our data and their data difficult. Although pressure was less than 20 cm H2O for a large percentage of time in our patients, an audible leak was not observed, and the low exhaled volume alarm on the ventilator was not triggered. Audible leaks and triggering of the alarm are typically considered indicators of an endotracheal tube cuff leak, and some may argue that the cuff therefore had an adequate seal. However, silent aspiration is still possible,28,58 and episodes of low pressure may increase the risk for aspiration and VAP.6,7


Endotracheal tube placement predicted the percent of time cuff pressure was low.

 

Although not statistically significant, pressure tended to decrease in 3 patients. Decreases over time have been noted in other small studies.50,51 In this study, changes in pressure occurred with endotracheal tube suctioning, patient activity, procedures, and positioning. This finding supports findings from case studies.27,28,52,53 In our study, patients who were more sedated and had a lower GCS score had less variation in pressure compared with patients who were less sedated and had higher GCS scores. More frequent monitoring of cuff pressure may be needed in patients who are less sedated with a higher level of consciousness who have greater fluctuation in cuff pressures.

In an exploratory predictive analysis, GCS scores and elevation of the head of the bed were significant predictors of the percentage of time the cuff pressure was high. Compared with patients with lower GCS scores, patients with higher GCS scores (and higher level of consciousness) had more movement and other activity that resulted in more episodes of transient increases in cuff pressure. Elevation of the head of the bed may also affect neck position and therefore be associated with changes in cuff pressure.52

Placement of the endotracheal tube (as measured by centimeter markings at the lip line) was a significant predictor of the percentage of time cuff pressures were low. Tubes that were inserted deeper into the trachea were associated with a greater frequency of lower cuff pressure. The depth of the endotracheal tube may be a factor that can be managed to better maintain cuff pressure. Additional research in this area is warranted; the distance of the tip of the endotracheal tube from the carina will be measured in future studies. Patients had been intubated for various lengths of time at the start of the study, a situation that might have affected the findings. Although not statistically significant, this variable was included in the model that predicted the percentage of time cuff pressure was low. The predictors identified through multiple regression analysis should be considered preliminary findings, because the sample size was small and therefore associated with a greater risk of a type I error.56

An unanticipated finding was that 16% of cuff pressures were higher than 30 cm H2O. In past studies,10,15,18,20 cuff pressures were high when the pressure was estimated, when routine measurements of cuff pressure were not done, and after anesthesia. The transient increases in pressure associated with suctioning and activity were included in this analysis, a step that may provide an overestimate of the amount of time a patient is at risk for complications. However, the purpose of this pilot study was to describe the natural history of cuff pressure during the study period. Omitting these known transient increases in pressure from the analysis may be indicated in future studies.

In particular, patient 1 (Figure 2Go) had high pressure for 69% of measurements. She was being weaned from sedative medications and mechanical ventilation and was extremely anxious; these factors may warrant additional assessment. Patients with a baseline pressure of 24 cm H2O had a greater frequency of higher pressure during the study than did patients with lower baseline pressures, so identification of the optimum pressure when intermittent measurement is done is indicated in future studies.

This study has several limitations. It was a pilot study and so is limited by the small sample size. The cuff pressure was adjusted to a minimum of 20 cm H2O at the beginning of the study; however, the starting pressure was higher than this value for 7 patients who had the pressure adjusted by the respiratory therapist immediately before the study. The protocol established a minimum starting value to avoid interfering with the standard of care in place on the units. The targeted duration of data collection was 12 hours. Data were collected for 3 of the patients for a mean of 4.2 hours because of factors beyond our control (eg, extubation, change in ventilator mode). The other 7 patients had data collected for approximately 11.5 hours. The data collection time was less than the targeted 12 hours because of change-of-shift patient activities and equipment setup and troubleshooting. A subanalysis indicated no significant differences for the cuff pressure data reported in Table 3Go and demographic data between the 3 patients with shorter periods of data collection and the 7 patients who had data collected for 11.5 hours.

Although many data were obtained, they did not reflect the entire duration of the patients’ intubation and mechanical ventilation. Data on outcomes such as aspiration and VAP were not part of the study design.


   Summary
Top
 Abstract
 Background
 Method
 Results
 Discussion
 Summary
References
 
Continuous monitoring of endotracheal tube cuff pressure is feasible and accurate and can be performed safely under the direct supervision of researchers. Cuff pressure varied widely across patients. Additional research is needed to identify further the influence of activities and other characteristics of patients that influence endotracheal tube cuff pressure. Opportunities still exist to optimize management of endotracheal tube cuff pressure.


   ACKNOWLEDGMENTS
 
This research was performed at the University of Central Florida College of Nursing and Orlando Regional Medical Center.

To purchase electronic or print reprints, contact The InnoVision Group, 101 Columbia, Aliso Viejo, CA 92656. Phone, (800) 899-1712 or (949) 362-2050 (ext 532); fax, (949) 362-2049; e-mail, reprints{at}aacn.org.

FINANCIAL DISCLOSURES
The study was funded by an American Association of Critical-Care Nurses–Philips Medical Systems Clinical Outcomes Grant.

eLetters
Now that you’ve read the article, create or contribute to an online discussion on this topic. Visit www.ajcconline.org and click "Respond to This Article" in either the full-text or PDF view of the article.

SEE ALSO
For more about endotracheal cuff pressures and how they relate to ventilator-associated pneumonia, visit the Critical Care Nurse Web site, www.ccnonline.org, and read the article by Augustyn, "Ventilator-Associated Pneumonia: Risk Factors and Prevention" (August 2007).


   REFERENCES
Top
 Abstract
 Background
 Method
 Results
 Discussion
 Summary
 References
 

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