A management option for leaking endotracheal tube cuffs: use of lidocaine jelly.

STUDY OBJECTIVE

To evaluate the effectiveness of methods for sealing a small endotracheal tube cuff perforation.

DESIGN

Randomized evaluation in an in vitro model of mechanical ventilation. In addition, two pertinent cases are reported.

SETTING

Operative anesthesia service in a large tertiary referral center.

INTERVENTIONS

A transparent acrylic "trachea" attached to a rubber breathing bag ("lung") was intubated with an 8.0 mm endotracheal tube. Positive pressure mechanical ventilation was begun and baseline minute ventilation recorded. After equilibrium, the endotracheal tube cuff was perforated in a standard fashion, and one of four "treatments" was applied in random sequence. Group A endotracheal tubes (n = 7) were managed by increasing fresh gas flow and manually injecting air into the cuff. Group B cuffs (n = 8) were insufflated with oxygen to maintain cuff pressure at 25 to 28 mmHg. In Groups C (n = 8) and D (n = 9), an 8 ml mixture of 2% lidocaine hydrochloride jelly (Xylocaine, Astra, Westborough, MA), and saline was injected into the cuff at a dilution of 1:3 and 1:1, respectively.

MEASUREMENTS AND MAIN RESULTS

Measurements included minute ventilation, airway pressure, and intracuff pressure. During the 30-minute observation period after cuff perforation, total exhaled ventilation was assessed and wasted ventilation calculated. Group A wasted ventilation (means +/- SD) was significantly greater (112 +/- 20 liters, p less than 0.01) than Groups B, C, and D (12 +/- 12 liters, 10 +/- 5 liters, and 18 +/- 13 liters, respectively). In Group A, it was impossible to maintain adequate minute ventilation. To remain inflated, Group B cuffs required insufflation at a rate of 10 to 80 ml/min. Groups C and D maintained an excellent cuff seal, but 2 of 9 Group D cuffs could not be deflated, while all Group C cuffs were deflatable. Also reported are two cases of persistent intraoperative endotracheal tube cuff leaks refractory to conventional management. Inflation of the endotracheal tube cuff with a lidocaine jelly-saline mixture successfully eliminated the leak, allowing completion of the procedure without reintubation.

CONCLUSIONS

The authors' in vitro results, in conjunction with the observations from their two cases, suggest that lidocaine jelly mixed with 1 to 3 parts normal saline may be useful in managing certain types of endotracheal tube cuff incompetence.