OBJECTIVE: Gas leakage around the cuff of a tracheal tube may frequently occur after tracheal intubation and inflation of the cuff. We assessed if the SmartCuff (Smiths Medical Japan, Tokyo, Japan), an automatic cuff pressure controller, would effectively prevent gas leakage.
METHODS: Seventy adult patients were allocated randomly to one of two groups. After induction of general anesthesia and tracheal intubation, in one group (Syringe group), a syringe was used to inflate the cuff, until there was no audible gas leakage, at the airway pressure at 20 cmH2O. In the other group (SmartCuff group), the SmartCuff was used to maintain the cuff pressure to be 20 cmH2O. The mechanical ventilation (tidal volume of 8 ml.kg-1 and 12 breaths per min) was started. The incidence and percentage of gas leakage, and the proportion of adequate seal (defined as gas leakage of < 10%) between the groups were compared.
RESULTS: The incidence of audible gas leakage was significantly higher in the Syringe group (10 of 35 patients (28%)) than in the SmartCuff group (none of 35 patients (0%)) (P = 0.00046, 95%CI for difference: 15-43%), and the proportion of adequate seal was significantly lower in the Syringe group (19 of 35 patients (54%)) than in the Smart cuff group (33 of 35 patients (94%)) (P = 0.0001, 95% CI for difference: 20-58%).
CONCLUSIONS: Gas leakage may frequently occur after tracheal intubation, and the use of the SmartCuff can effectively maintain the sealing effect of the cuff.

The laryngeal mask airway (LMA) is commonly used for airway management. Cuff hyperinflation has been associated with complications, poor ventilation and increased risk of gastric insufflation. This study was designed to determine the best cuff inflation method of AuraOnce™ LMA during bronchoscopy and EBUS (Endobronquial Ultrasound Bronchoscopy) procedure. We designed a Randomized controlled, doble-blind, clinical trial to compare the efficacy and safety of three cuff inflation methods of AuraOnce™ LMA. 210 consenting patients scheduled for EBUS procedure under general anesthesia, using AuraOnce™ LMA were randomized into three groups depending on cuff insufflation: residual volume (RV), half of the maximum volume (MV), unchanged volume (NV). Parameters regarding intracuff pressure (IP), airway leak pressure (OLP), leakage volume (LV) were assessed, as well as postoperative complications (PC). 201 (95.7%) patients completed the study. Mean IP differed between groups (MV: 59.4 ± 32.4 cm H2O; RV: 75.1 ± 21.1 cm H2O; NV: 83.1 ± 25.5 cmH20; P < 0.01). The incidence of IP > 60 cmH2O was lower in the MV group compared to the other two (MV: 20/65(30.8%); RV:47/69 (68.1%); NV 48/67 (71.6%); p < 0.01). The insertion success rate was 89,6% (180/201) at first attempt, with no difference between groups (p = 0.38). No difference between groups was found either for OLP (p = 0.53), LV (p = 0.26) and PC (p = 0.16). When a cuff manometer is not available, a partial inflation of AuraOnce™ LMA cuff using MV method allows to control intracuff pressure, with no significant changes of OLP and LV compared to RV and NV insufflation method.Registration clinical trial: NCT04769791.

UNASSIGNED: During esophagogastroduodenoscopy (EGD), general anesthesia (GA) may be provided using a laryngeal mask airway (LMA) with the endoscope inserted behind the cuff of the LMA into the esophagus. Passage of the endoscope may increase the intracuff of the LMA. We evaluated a newly designed LMA (LMA® Gastro™ Airway) which has an internal channel exiting from its distal end to facilitate EGD. The current study compared the change of LMA cuff pressure between this new LMA and a standard clinical LMA (Ambu® AuraOnce™) during EGD.
UNASSIGNED: Patients less than 21 years of age and weighing more than 30 kg were randomized to receive airway management with one of the two LMAs during EGD. After anesthetic induction and successful LMA placement, the intracuff pressure of the LMAs was continuously monitored during the procedure. The primary outcome was the change of intracuff pressure of the LMAs.
UNASSIGNED: The study cohort included 200 patients (mean age 13.6 years and weight 56.6 kg) who were randomized to the LMA® Gastro™ Airway (n=100) or the Ambu® AuraOnce™ LMA (n=100). Average intracuff pressures during the study period (before and after endoscope insertion) were not different between the two LMAs. Ease of the procedure was slightly improved with the LMA® Gastro™ Airway (p<0.001).
UNASSIGNED: The LMA® Gastro™ Airway blunted, but did not prevent an increase in intracuff pressure during EGD when compared to the Ambu® AuraOnce™ LMA. Throat soreness was generally low, and complications were infrequent in both groups. The ease of the procedure was slightly improved with the LMA® Gastro™ Airway compared to the Ambu® AuraOnce™ LMA.

BACKGROUND: The cuff of an endotracheal tube seals the airway to facilitate positive-pressure ventilation and reduce subglottic secretion aspiration. However, an increase or decrease in endotracheal tube intracuff pressure can lead to many morbidities.
OBJECTIVE: The main purpose of this study is to investigate the effect of different head and neck positions on endotracheal tube intracuff pressure during ear and head and neck surgeries.
METHODS: A total of 90 patients undergoing elective right ear (Group 1: n=30), left ear (Group 2: n=30) or head and neck (Group 3: n=30) surgery were involved in the study. A standardized general anesthetic was given and cuffed endotracheal tubes by the assistance of video laryngoscope were placed in all patients. The pilot balloon of each endotracheal tube was connected to the pressure transducer and standard invasive pressure monitoring was set to measure intracuff pressure values continuously. The first intracuff pressure value was adjusted to 18.4mmHg (25cm H2O) at supine and neutral neck position. The patients then were given appropriate head and neck positions before related-surgery started. These positions were left rotation, right rotation and extension by under-shoulder pillow with left/right rotation for Groups 1, 2 and 3, respectively. The intracuff pressures were measured and noted after each position, at 15th, 30th, 60th, 90th minutes and before the extubation. If intracuff pressure deviated from the targeted value of 20-30cm H2O at anytime, it was set to 25cm H2O again.
RESULTS: The intracuff pressure values were increased from 25 to 26.73 (25-28.61) cm H2O after left neck rotation (p=0.009) and from 25 to 27.20 (25.52-28.67) cm H2O after right neck rotation (p=0.012) in Groups 1 and 2, respectively. In Group 3, intracuff pressure values at the neutral position, after extension by under-shoulder pillow and left or right rotation were 25, 29.41 (27.02-36.94) and 34.55 (28.43-37.31) cm H2O, respectively. There were significant differences between the neutral position and extension by under-shoulder pillow (p<0.001), and also between neutral position and rotation after extension (p<0.001). However, there was no statistically significant increase of intracuff pressure between extension by under-shoulder pillow and neck rotation after extension positions (p=0.033).
CONCLUSIONS: Accessing the continuous intracuff pressure value measurements before and during ear and head and neck surgeries is beneficial to avoid possible adverse effects/complications of surgical position-related pressure changes.

Hyperinflation of laryngeal mask cuffs may carry the risk of airway complications. The manufacturer recommends inflating cuff until the intracuff pressure reaches 60 cmH2O, or inflate with the volume of air to not exceed the maximum recommended volume. We prospectively assessed the correlation of cuff inflating volumes and pressures, and the appropriated the cuff inflating volumes to generate an intracuff pressure of 60 cmH2O in the adult laryngeal masks from different manufacturers.
Two groups of 80 patients requiring laryngeal mask size 3 and 4 during general anesthesia were randomized into 4 subgroups for each size of the laryngeal mask: Soft Seal® (Portex®), AuraOnce™ (Ambu®), LMA-Classic™ (Teleflex®) and LMA-ProSeal™ (Teleflex®). After insertion, the cuff was inflated with 5-ml increments of air up to the maximum recommended volume. After each 5-ml intracuff pressure was measured, the volume of air that generated the intracuff pressure of 60 cmH2O was recorded.
Mean (SD) volume of air required to achieve the intracuff pressure of 60 cmH2O in Soft Seal®, AuraOnce™, LMA-Classic™, LMA-ProSeal™ laryngeal mask size 3 were 11.80(1.88), 9.20(1.88), 8.95(1.50) and 13.50(2.48) ml, respectively, and these volumes in laryngeal mask size 4 were 14.45(4.12), 12.55(1.85), 11.30(1.95) and 18.20(3.47) ml, respectively. The maximum recommended volume resulted in high intracuff pressures (> 60 cmH2O) in all laryngeal mask types and sizes studied.
Pressure-volume curves of adult laryngeal masks are all in sigmoidal shape. Cuff designs and materials can effect pressure and volume correlation. Approximately half of the maximum recommended volume is required to achieve the intracuff pressure of 60 cmH2O except LMA-ProSeal™ which required two-thirds of the maximum recommended volume.
Thai Clinical Trials Registry, TCTR20150602001, May 28, 2015.

BACKGROUND: Endotracheal intubation (ETI) for mechanical ventilation has a central role in the Intensive Care Unit (ICU). ETI is one of the main risk factors for the development of ventilator-associated pneumonia (VAP) as its presence reduces the natural defences of the upper airway and allows the micro-suction of secretions in the airways. In order to minimise such complications, it is fundamental to maintain a suitable pressure inside the tube cuff.
OBJECTIVE: The main objective of the present study is to evaluate the effectiveness and reliability of palpation method, performed with the operators fingers, for detecting the tube cuff pressure.
RESULTS: The study was performed using a manikin to test the pressure of the ETT cuff, on a sample constituted by nurses employed in three Italian ICU from two different Umbrian hospitals. From a total of 68 participants, detection by palpation method revealed to be not correct in 68% of cases; in particular, only 10% of respondents can correctly detect a pressure in the recommended range (20-30cmH2O) using palpation. Moreover it was possible to highlight that the participation in emergency courses has a positive effect on the correct measurement of cuff pressure using the palpation method (V=0.501).
CONCLUSIONS: The study, in agreement with the literature, confirms the thesis that the palpation method is inadequate to determine an estimate of the pressure existing inside the cuff.