The Changes of Endotracheal Tube Cuff Pressure during Manual and Intermittent Controlling in Intensive Care Units

Factors associated with lack of tracheal sealing by a cuff inflated to more than 30 cmH2O during mechanical ventilation: A cross-sectional study

Objectives

The cuff pressures > 30 cmH2O may create a seal in the trachea. The objective of this study was to identify risk factors associated with lack of tracheal sealing by an endotracheal cuff inflated to > 30 cmH2O in patients undergoing mechanical ventilation.

Methods

This prospective cross-sectional study was conducted from 2019 to 2020 in the cardiothoracic intensive care unit and respiratory medical care unit of a Hospital in Nantong, China. Patients aged >16 years undergoing cardiothoracic surgery with mechanical ventilation using endotracheal intubation were included. Patient characteristics and ventilator parameters were analyzed. Cuff pressure was maintained with the minimum leak technique (MLT) and measured with a cuff pressure gauge. Cuff pressure was measured for 30 seconds when ventilation was accompanied by no leak, simultaneously detected by the ventilator or auscultation with a stethoscope.

Result

Of 352 patients undergoing mechanical ventilation, 51 patients (14.5%) had a cuff pressure of >30 cmH2O. Multivariable analysis showed that cuff manufacturer (Guangzhou Weili) and nasal endotracheal intubation significantly increased the risk of an unsealed trachea. Peak inspiratory pressure, cuff diameter and male sex had a strong inverse association with an unsealed trachea.

Conclusions

These findings suggest that an endotracheal cuff pressure of 20 to 30 cmH2O is adequate for most patients, but lack of a tracheal seal still occurs in a small number of people. An unsealed trachea is most likely because cuff and tracheal diameters do not match. Clinical Trial Registration: http://www.chictr.org.cn/index.aspx Unique identifier: ChiCTR-COC-15006459.

Intermittent versus continuous control of tracheal cuff pressure in patients undergoing mechanical ventilation: A systematic review and meta-analysis

AIMS AND OBJECTIVES

To evaluate the effects and safety of intermittent versus continuous control of cuff pressure in patients with mechanical ventilation.

BACKGROUND

Tracheal cuff pressure management is vital to the prognosis of patients with mechanical ventilation.

DESIGN

A meta-analysis.

METHODS

This meta-analysis was conducted and reported according to the PRISMA checklist. We searched Pubmed, Embase, The Cochrane Library, BMJ Best Practice, Web of Science, ProQuest Dissertations, as well as the Chinese Biomedical Literature Database, Wanfang, and China national knowledge infrastructure databases up to 5 August 2022 for randomised controlled trials (RCTs) on the intermittent versus continuous control of cuff pressure. Review Manager 5.3 software was used for relevant data analysis.

RESULTS

A total of 18 RCTs involving 1998 patients with mechanical ventilation were included. The synthesised outcomes indicated that continuous control of cuff pressure is beneficial to reduce the incidence of ventilator-associated pneumonia (VAP) [RR = 0.41, 95%CI (0.35, 0.49)], aspiration [RR = 0.36, 95%CI (0.21, 0.63)], duration of mechanical ventilation [MD = -3.23, 95%CI (-4.66, -1.79)], length of ICU stay [MD = -4.12, 95%CI (-5.40, -2.83)], and increase the volume of subglottic drainage [MD = 18.54, 95%CI (16.50, 20.58)]. There was no significant difference in the mortality between two groups [RR = 1.01, 95%CI (0.84, 1.21)]. Egger regression analyses showed that there were no obvious publication biases in the synthesised results (all p > .05).

CONCLUSIONS

Existing evidence shows that compared with intermittent monitoring of cuff pressure, continuous monitoring of cuff pressure can reduce the occurrence of aspiration and VAP, shorten the patient's duration of mechanical ventilation and length of ICU stay.

RELEVANCE TO CLINICAL PRACTICE

Continuous monitoring of cuff pressure is more beneficial and should be promoted in clinical nursing care of patients undergoing mechanical ventilation.

Could clinical nursing procedures lead to tracheal cuff pressure drop? A prospective observational study

AIM

To evaluate the dynamic changes in tracheal cuff pressure before and after four clinical nursing procedures including sputum suction, oral care, atomisation inhalation, and turning over, and thus provide references for the adjustment time of cuff pressure in clinical practice.

BACKGROUND

Cuff pressure must be kept within the range of 25-30 cmH₂ O to ensure effective ventilation and prevent aspiration, while maintaining tracheal blood flow perfusion.

DESIGN

A prospective observational study.

METHODS

The cuff pressure of 56 intubated patients was adjusted to 28-30 cmH₂ O. A cuff pressure monitor was used to continuously monitor cuff pressure changes before and after four clinical nursing procedures (sputum suction, oral care, atomisation inhalation, and turning over) and the cuff pressures at various time points were compared. The semi-quantitative cough strength score (SCSS) was used to evaluate cough strength during sputum suction and the effect of cough strength on cuff pressure during sputum suction. This study followed the STROBE checklist for cross-sectional studies.

RESULTS

The cuff pressures during the four clinical nursing procedures of sputum suction, atomisation inhalation, turning over, and oral care, all temporarily increased (p < 0.001) and decreased to varying degrees 20 min later (p < 0.001). Among them, the cuff pressure rose the highest under a state of moderate or strong coughing during sputum suction (78.38 ± 12.13 cmH₂ O) and dropped the most at 20 min after the procedure (21.71 ± 4.80 cmH₂ O).

CONCLUSIONS

The four clinical nursing procedures of sputum suction, atomisation inhalation, turning over, and oral care can all cause different degrees of cuff pressure drop. The decision on whether the cuff pressure needs to be corrected depends on the specific situation.

RELEVANCE TO CLINICAL PRACTICE

During clinical practice, the cuff pressure can be individually corrected according to different clinical nursing procedures, which can increase the qualified rate of cuff pressure and reduce the workload of nurses.

The effect of different inflating volume on the measurement accuracy of the modified cuff pressure measurement method

To evaluate the effect of different inflation volume on the measurement accuracy of the modified cuff pressure measurement method in different shapes of cuffs, so as to provide reference for the correct monitoring of cuff pressure in clinic. In vitro study: The traditional cuff pressure measurement method (the cuff pressure gauge before measurement shows 0 cm H₂O) and the modified cuff pressure measurement method (the cuff pressure before measurement shows 25 cm H₂O, 28 cm H₂O, 30 cm H₂O or 32 cm H₂O) were used to measure cylindrical and tapered cuffs, and the effect of different inflation volume on cuff pressure was analyzed statistically. Clinical study: patients with the artificial airway established by orotracheal intubation or tracheotomy in Neuro-ICU were prospectively selected as subjects, and the measurement procedure was the same as in vitro study. In vitro study showed that the pressure loss values of cylindrical cuff and tapered cuff using the traditional cuff pressure measurement method were (3.75 ± 0.31) cm H₂O and (4.92 ± 0.44) cm H₂O, respectively, and clinical study showed that the pressure loss values were (5.07 ± 0.83) cm H₂O and (5.17 ± 0.93) cm H₂O, respectively. The actual measured values measured by the traditional cuff pressure measurement method of the two cuff shapes were compared with the corrected target value of 28 cm H₂O, and the differences were statistically significant (P < 0.000). Both in vitro and clinical study had shown that all differences between the actual measured value and the corrected target value using the modified cuff pressure measurement method (measured with 25 cm H₂O, 30 cm H₂O, 32 cm H₂O) were statistically significant (P < 0.000), and the range of overall differences was (0-1.23 ± 0.25) cm H₂O. In vitro study had shown that the pressure variation coefficient (CV) of the tapered cuff was greater than that of the cylindrical cuff, and the difference was statistically significant (3.08 ± 0.25 VS 2.41 ± 0.21, P < 0.000). The traditional cuff pressure measurement method can directly lead to the cuff pressure drop, which is easy to cause the leakage of secretions on the cuffs and the misjudgment of the cuff pressure by medical personnel. However, the modified cuff pressure measurement method can effectively reduce cuff pressure loss, and taking the actual cuff pressure value as the inflation volume is the highest measurement accuracy.The tapered cuff is more susceptible to air volume, so it is necessary to pay attention to its measurement and correction in clinical practice.

Effect of Tracheal Suctioning on Cuff Pressure in Mechanically Ventilated Patients: a Quasi-Experimental Study

BACKGROUND

Endotracheal tube cuff pressure must be kept in an optimal range, but it might change during some nursing procedures. If the cuff pressure gets outside the normal range, it can cause mucosal damage, insufficient ventilation, and microaspiration. This study aimed to determine the effect of endotracheal suctioning on cuff pressure in patients during mechanical ventilation.

MATERIALS AND METHODS

This is a quasi-experimental study utilizing repeated measures with a within-subject design. Using a simple convenience sampling method, 61 patients were studied during intubation on mechanical ventilation. Baseline cuff pressure was adjusted to 25 cm H ₂ O. Then, at 15, 30, and 60 minutes' intervals, cuff pressures were measured once without suctioning and again after suctioning.

RESULTS

The results showed a significant change in the mean endotracheal tube cuff pressure during suctioning (p<0.001, d=7.47). During suctioning, cuff pressure exceeded the normal range in 64% of the patients. After suctioning, although endotracheal tube cuff pressure decreased in both conditions, it decreased more significantly (F (2.17, 260.55)=238.19, p<0.001, ν=0.665, d=1.37) in the suctioning condition.

CONCLUSION

The results suggest that endotracheal tube cuff pressure increases suddenly and briefly during suctioning, but within 60 minutes after suctioning, it becomes more reduced in suctioning conditions than without suctioning. Therefore, patients are at risk of mucosal damage and microaspiration after and during suctioning, respectively. It is suggested that nurses use continuous cuff pressure regulation methods to prevent potential risks.