Evaluation of tracheal cuff pressure variation in spontaneously breathing patients

Behavior of Endotracheal Tube Cuff Pressure During a Routine Control Maneuver With Different Manometers

BACKGROUND

The main functions of the endotracheal tube (ETT) cuff are to prevent aspiration and to allow pressurization of the respiratory system. For this purpose, it is essential to maintain adequate pressure inside the cuff, thus reducing the risks for the patient. It is regularly checked using a manometer and is considered the best alternative. The objective of this study was to evaluate the cuff pressure behavior of different ETTs during the simulation of an inflation maneuver using different manometers.

METHODS

A bench study was performed. Four brands of 8-mm internal diameter single lumen with a Murphy eye ETT with cuff and 3 different brands of manometers were used. In addition, a pulmonary mechanics monitor was connected to the inside of the cuff through the body of the distal end of the ETT.

RESULTS

A total of 528 measurements were made on the 4 ETTs. During the complete procedure (connection and disconnection), there was a significant pressure drop of 7 ± 1.4 cm H2O from the initial pressure (Pinitial) (P < .001), of which 6 ± 1.4 cm H2O was lost during connection (difference between Pinitial and Pconnection). The Preconnection value was 19.1 ± 1.6 cm H2O, showing a significant total pressure drop of 11 ± 1.6 cm H2O (difference between Pinitial and Preconnection) (P < .001). The Pfinal mean was 29.6 ± 1.3 cm H2O. Significant differences were found between manometers according to the time of measurement. A similar phenomenon was evidenced when analyzing different ETTs.

CONCLUSIONS

Significant pressure changes occur secondary to ETT cuff measurement, which has important implications for patient safety.

Objective and Subjective Evaluation of Endotracheal Tube Cuff Pressure between Different Levels of Anesthesia Experiences

Objective: After endotracheal intubation (ETI), the endotracheal tube cuff (ETTc) should be inflated at sufficient pressure to function, and high pressure should be avoided to prevent complications. In our study, the effect of professional experience on the estimation of ETTcP by palpation is investigated. Method: The study included 75 adult patients with physical status I-III of the American Society of Anesthesiology (ASA) scheduled for ETI. Anesthesia residents were divided into two groups of 20, each with 1 month to 1 year of experience (Group 1) and those with more than 4 years of experience (Group 2). After the ETI, one participant in both groups was asked to inflate the ETTc to an estimated 25 cm H2O by cuff palpation. Then the actual ETTcP was measured with a manometer. Results: The median ETTcP value was 42,00 cm H2O in Group 1 and 32,00 cm H2O in Group 2, (p=0.012). Although the data of both groups were significantly higher than the target value, the values obtained in Group 1 were further away from Group 2 (p&lt;0.001, p&lt;0.001). Conclusion: Professional experience has no effect on the correct estimation of the ETTcP. It is more convenient to measure the actual pressure to avoid undesirable effects of ETTcP outside the target.

Continuous Endotracheal Tube Cuff Pressure Control Decreases Incidence of Ventilator-Associated Pneumonia in Patients with Traumatic Brain Injury

BACKGROUND

Ventilator-associated pneumonia (VAP) is a common cause of morbidity and mortality in intensive care unit (ICU), and among the several preventative strategies described to reduce the incidence of VAP, the most important is the endotracheal tube cuff (ETC) pressure. The present study was conducted on 60 patients who required mechanical ventilation (MV) in the ICU with traumatic brain injury (TBI).

METHODS

The patients were randomized into two groups of 30, in which ETC pressure was regulated using a smart cuff manager (SCM) (Group II), or manual measurement approach (MMA) (Group I). Demographic data, MV duration, length of ICU stay and mortality rates were recorded. The clinical pulmonary infection scores (CPISs), C-reactive protein (CRP) values, and the fraction of inspired oxygen (FiO2) and positive end-expiratory pressure (PEEP) values of the groups were compared at baseline, and at hours 48, 72 and 96.

RESULTS

In Group I, CPIS values significantly higher than Group II in 48th, 72nd and 96th hours (p < 0.05). In Group I, PEEP values and deep tracheal aspirate (DTA) culture growth rates significantly higher than Group II in 72nd and 96th hours (p < 0.05).

CONCLUSION

The continuous maintenance of ETC pressure using SCM reduced the incidence of VAP.

Comparison of endotracheal tube cuff pressure values before and after training seminar

It is recommended that endotracheal cuff (ETTc) pressure be between 20 and 30 cm H₂O. In this present study, we intend to observe average cuff pressure values in our clinic and the change in these values after the training seminar. The cuff pressure values of 200 patients intubated following general anesthesia induction in the operating theatre were measured following intubation. One hundred patients whose values were measured before the training seminar held for all physician assistants, and 100 patients whose values were measured after the training seminar were regarded as Group 1 and Group 2, respectively. Cuff pressures of both groups were recorded, and the difference between them was shown. Moreover, cuff pressure values were explored according to the working period of the physician assistants. There was no significant difference between the groups in terms of age, gender and tube diameters. Statistically significant difference was found between cuff pressure values before and after the training (p < 0.001). Average pressure measure for Group I was 54 cm H₂O, while average pressure in Group II declined to 33 cm H₂O. It was observed that as the working period and experience of physician assistants increased, cuff pressure values decreased, however no statistically significant different was found (p < 0.375). We believe that clinical experience does not have significant effects on cuff pressure and that training seminars held at intervals would prevent high cuff pressure values and potential complications.