Achieving a Safe Endotracheal Tube Cuff Pressure in the Prehospital Setting: Is It Time to Revise the Standard Cuff Inflation Practice?

Abstract

Numerous studies have reported unsafe endotracheal tube (ETT) cuff pressures (CP) in the prehospital environment. The purpose of this study was to identify an optimal cuff inflation volume (CIV) to achieve a safe CP (20-30 cmH2O). This observational study utilized 30 recently harvested ovine tracheae, which were warmed from refrigeration in a water bath at 85°F prior to testing. Each trachea was intubated with five different ETT sizes (6.0-8.0 mm), and each size tube was tested with six cuff inflation volumes (5-10 cc). The order of ETT size for each trachea and CIV for each size ETT was randomly pre-assigned. Data were descriptively summarized and categorized before mixed-effects logistic regression was used to determine optimal CIV. Only 113 CP measurements (12.6%, N = 900) were within the optimal range (M = 54.75 cmH2O, SD = 38.52), all of which resulted from a CIV 6 or 7 cc (61% and 39%, respectively). CIVs of 5 cc (n = 150) resulted in underinflation (<20 cmH2O) in all instances, while CIVs of 8, 9, or 10 cc (n = 150 each) resulted in overinflation (>30 cmH2O) in all instances, regardless of ETT size. The odds of achieving a safe CP were greater with CIV of 6 cc for tube sizes 6.0 (OR = 15.9, 95% CI = 3.85-65.58, p < 0.01) and 6.5 mm (OR = 3.16, 95% CI = 1.06-9.39, p = 0.039); however, there was no significant difference in the odds of achieving a safe CP between CIV of 6 and 7 cc for tube sizes 7.0, 7.5, or 8.0 mm. Neither trachea circumference (M = 7.11 cm, SD = 0.40), nor tissue temperature (M = 81.32°F, SD = 0.93) were found to be significant predictors of CP (p = 0.20 and 0.81, respectively). Our study showed a high frequency of CP measurements outside of the desired norms. The CIV range of 6-7 cc resulted in the highest likelihood of achieving the desired cuff pressure range, while cuffs inflated with 8-10 cc resulted in dangerously high CPs in all instances. In the absence of a more ideal solution, the results of this study suggest that narrowing the recommended CIV from 5-10 cc to 6-7 cc might be a reasonable target for any tube size.

Frequent Versus Infrequent Monitoring of Endotracheal Tube Cuff Pressures

“…Many hospitals perform frequent routine monitoring of cuff pressures despite the absence of an audible leak or a loss of tidal volume. 1,13,14 If the results of our study can be confirmed by other centers, then these data could instill confidence in clinicians to change this practice and only monitor cuff pressures after intubation, after manipulation or adjustment of the endotracheal tube, and when clinically indicated for an air leak or a loss of tidal volume. The era of performing frequent routine assessments of cuff pressures may be coming to an end, as has been suggested for the assessment of frequent gastric residual volumes, due to the lack of observed clinical benefit of routine monitoring.…”

“…Currently there is no accepted standard for the frequency of monitoring endotracheal tube cuff pressure, and widely different strategies are reported to include continuous monitoring. 1 The implied goal of endotracheal tube cuff pressure monitoring is to maintain the cuff pressures between 20 -30 cm H 2 O to minimize air leaks and loss of tidal volume due to underfilling the cuff and to prevent injury to the tracheal mucosa due to overfilling the cuff. It is known that 20 -30% of cuff pressure measurements may deviate above or below this threshold.…”

“…It is known that 20 -30% of cuff pressure measurements may deviate above or below this threshold. 1 However, the impact of such deviation on clinical outcomes is not well described in the medical literature. 2 The 2 most common methods for assessing cuff pressures are using a manometer for direct measurement and performing a minimal leak, with the former being the most accepted method.…”

Comparison of tracheal tube cuff pressure with two technique: fixed volume and minimal leak test techniques

“…In the absence of a more ideal solution, the results of this study suggest that narrowing the recommended cuff inflation volume from 5-10 mL to 6-7 mL might be a reasonable target for any tube size. 20 Based on the different methods and various results, we designed a trial to compare the tracheal cuff pressure measurement by two methods: fixed volume and MLT.…”

Do we know how to properly seal the supraglottic airway devices cuff? Pilot data

“…In the worldwide scientific literature, we can find a large number of confirmations of the significant influence of pressure in the cuff sealing the intubation tube or supraglottic ventilation devices on the rate of complications related to airway devices [7][8][9]. They indicate how important a parameter in patient care is to maintain the correct pressure range in the sealing cuff.…”