Endotracheal Tube Cuff Inflation Research Articles

Comparative study of endotracheal tube cuff inflation with air versus alkalinized lidocaine on hemodynamic response during extubation

Comparative study of endotracheal tube cuff inflation with air versus alkalinized lidocaine on hemodynamic response during extubation

A rare case of endotracheal tube cuff leakage with no detectable decrease in cuff pressure.

Common causes of air leakage around an endotracheal tube include insufficient endotracheal tube cuff inflation and damage to the cuff, while damage to the pilot balloon or pilot balloon tubing is relatively rare. A 74-year-old female with vertebral osteomyelitis was scheduled for an extreme lateral interbody fusion followed posterior fixation. A fiber-optic light was utilized as part of the surgical illuminator. A sudden decrease in tidal volume and airway pressure was noted intraoperatively. We suspected leakage around the endotracheal tube cuff; however, no decrease in cuff pressure was detected. Despite the normal cuff pressure, we decided to inject a small amount of air which led to a significant increase in the cuff pressure. Upon careful inspection of the endotracheal tube, we discovered that the pilot balloon tubing was damaged as a result of thermal energy emitted by the fiber-optic light, which had ignited the surgical drape. The pilot balloon tubing was partially severed in which the section proximal to the endotracheal tube cuff was burned and punctured, causing the cuff leak. Meanwhile, the section proximal to the pilot balloon had melted and occluded the lumen, resulting in a falsely normal cuff pressure reading followed by an elevated cuff pressure when a small amount of air was injected into the pilot balloon during troubleshooting. Appropriate ventilation was resumed after extubation and re-intubation with a new endotracheal tube. We experienced an endotracheal tube cuff leakage caused by a damaged pilot balloon tubing due to thermal energy of the fiber-optic light. Our case report emphasizes the importance of suspecting damage to the endotracheal tube cuff and inflation system despite a normal cuff pressure reading, given that the measurement may be falsely elevated depending on the specific location of the damage. In addition, all operating personnel should be familiarized with safety warnings and cautions related to handling.

Alkalized lidocaine in endotracheal tube cuff inflation in patients undergoing thyroidectomy surgery: a clinical trial.

The aim of the study was to compare the postoperative effects of endotracheal tube cuff inflation with alkalized lidocaine in patients undergoing thyroidectomy surgery. This is a randomized, double-blind clinical trial between August 2020 and August 2022 at the Hospital São Domingos, São Luís, Maranhão, Brazil. Patients over 18 years who underwent thyroidectomy of both sexes, American Society of Anesthesiologists (ASA) I or ASA II, were included. Patients with difficult orotracheal intubation, smoking, cuff rupture during orotracheal intubation, heart, lung, or neuropathies, previous surgery of the larynx or trachea, with risk of aspiration of gastric contents, or with the need to use a nasogastric tube were excluded. Patients were randomly selected and divided into the control group, whose cuff was filled with 0.9% saline solution, and the alkalinized lidocaine group, where the cuff was filled with 2% lidocaine and 8.4% sodium bicarbonate. The control group had higher systolic blood pressure [137 (94-183) mmHg] medians after extubation than the alkalinized lidocaine group [127 (82-189) mmHg] (p=0.03). The same was observed in heart rate values [control group: 86 (62-120); alkalinized lidocaine group: 80 (53-120)] (p=0.034). The alkalinized lidocaine group showed a significant increase in the ability to sustain phonation in the 24 h postoperatively, from 82.0 to 98.0% (p=0.031). There was no protective effect of the use of alkalinized lidocaine on the sensation of swallowing and complaints after thyroidectomy surgery. There was a significant improvement in hemodynamic response in the intervention group after extubation.

An innovative method of dilating tracheal stenosis by using endotracheal tube cuff inflation.

An innovative method of dilating tracheal stenosis by using endotracheal tube cuff inflation.

The effect of using personal protective equipment and aerosol box in the emergency department on the intubation times.

Endotracheal intubation is a procedure commonly performed in the emergency department (ED). Endotracheal intubation poses a risk of exposure to infectious aerosol droplets. The present study aims to test the effect of using an aerosol box (AB) and personal protective equipment (PPE) on the intubation time while performing endotracheal intubation manikin. The study participants (11 emergency specialists, 11 emergency physicians, and 11 general practitioners) performed endotracheal intubation on a training manikin in three different airway simulations. Simulation 1 had neither PPE nor AB, simulation 2 had PPE, and simulation 3 had both PPE and AB. The intubation times, the number of intubation attempts, and the discomfort caused by the AB were recorded. There was no significant difference in the number of intubation attempts between the physicians according to their position and airway simulations (p > 0.05). There was a significant difference at all time points except for the time to endotracheal tube cuff inflation in three different airway simulations using PPE and an AB (p < 0.05). The median intubation times were longer using PPE and an AB. The use of PPE and an AB significantly increases the total intubation time.

Endotracheal tube cuff inflation pressure varieties and response to education among anesthetists

ABSTRACT Background This study aimed to evaluate endotracheal tube (ETT) cuff inflation pressure (CIP) applied by anesthetists as well as the effect of an interview and feedback on their CIP accuracy. Methods This single-blind, controlled trial involved two series of CIP measurements in intubated patients before and after an interview and feedback of the participating anesthetists who were asked to inflate the cuffs for all intubated patients as per their clinical judgment. The cuff pressures were measured using a manometer and accordingly adjusted to 25 cm H2O by the researchers. For each anesthetist, 3 measurements were recorded, and the mean pressure values were calculated for each setting. The anesthetists were initially blinded, then they were informed about the pressure values and the adjustments. The primary outcome was the anesthetists’ accuracy regarding ETT inflation following the feedback. The secondary outcomes were pressure values in senior and junior anesthetists as well as in scheduled and emergency operations. Results The study enrolled 28 anesthetists; six registrars or senior registrars and 22 residents. Interview and feedback significantly lowered the mean pressure applied by the anesthetists. The cuff inflation pressure decreased from 33.8 ± 1.95 to 30.8 ± 3.24 and from 32.9 ± 2.38 to 29.9 ± 3.44 for emergency and scheduled surgeries, respectively. Furthermore, the frequency of safe CIP increased significantly for both emergency and scheduled surgeries. However, the senior staff showed no significant increase in safety CIP. Conclusion Anesthetists improved their accuracy of CIP after educational feedback. ETT cuff pressures should be routinely measured in intubated patients under general anesthesia.

Methods Used for Endotracheal Tube Cuff Inflation and Pressure Verification in Veterinary Medicine: A Questionnaire on Current Practice.

Endotracheal intubation is a routine procedure in veterinary anaesthesia, yet no consensus guidelines exist for endotracheal tube (ETT) cuff inflation and pressure measurement. The aim of this study was to assess current practice of ETT cuff inflation and seal verification in veterinary medicine. An online questionnaire was distributed among veterinary professionals who administer anaesthesia, comprising six demographic and twelve ETT cuff-related questions per species. N = 348 questionnaires were completed. Cuff pressure was measured by 30% of respondents in cats, 32% in dogs and 9% in both farm animals and horses. Anaesthesia diplomates were not more likely to measure cuff pressure than others, except in cats (OR: 1.8; 95% CI: 1.1-2.9). The most frequently selected recommended range of cuff pressure was 20-30 cm H2O, regardless of species, although &gt;30 cm H2O was selected significantly more often in horses compared to dogs, cats and farm animals. The preferred technique to verify cuff seal was minimal occlusive volume in dogs, cats and farm animals, whereas in horses, the preferred method was verification of normal capnogram waveform. ETT cuff pressure measurement remains uncommon in veterinary anaesthesia. The development of consensus recommendations for cuff inflation, including evidence-based target cuff pressure ranges for various species and different ETT models or materials, can help to improve practice.

Effect on Cuff Pressure of Various Endotracheal Tube Cuff Inflation Methods

Objective: To compare mean endotracheal tube cuff pressures generated using two endotracheal tube cuff inflation methods;just-Seal versus Stethoscope-Guided in patients undergoing elective surgery under general Anaesthesia.&#x0D; Study Design: Quasi-experimental study.&#x0D; Place and Duration of Study: Anesthesia Department, Combined Military Hospital, Rawalpindi Pakistan, from Jan to Jul 2021.&#x0D; Methodology: A total of 100 patients undergoing elective surgery under general endotracheal tube anaesthesia between 18–60 years of age of either gender were included. Patients were equally allocated (n=50 each) to two Groups, A (Just Seal Group) and B (Stethoscope Guided Group). In the Group-A method, the air was injected until no air leak could be heard. The pressure was measured using a “Portex cuff pressure manometer”. In the Group-B method, a stethoscope bell was placed on the thyroid lamina, and harsh breath sounds were auscultated during ventilation. Cuff was inflated till the sounds changed to smooth sounds. The pressure was measured and then noted down. &#x0D; Results: Among 100 patients, 39 % were males, and 61 % were females. The mean endotracheal cuff pressure in Group-A was 39.90±3.19 centimetres of water and 28.42±3.52 centimetres of water, with Group-B (p-value of 0.001).&#x0D; Conclusion: Post-intubation cuff pressure measured in patients undergoing elective surgery under general anaesthesia of the just seal group is higher than that in the stethoscope-guided group.&#x0D; Keywords: Cuff pressure, Stethoscope-guided, Tracheal intubation.&#x0D;

The impact of esophageal device insertion on cuff pressure of endotracheal tube: a literature review and meta-analysis

The impact of intraoperative esophageal device insertion (EDI) on endotracheal tube (ET) cuff inflation pressure remains unclear. Electronic databases including Medline, Embase, Google scholar, Web of Science™ and Cochrane Central Register of Controlled Trials were searched for studies involving EDI after placement of ETs from inception to July 7, 2022. The primary outcome was risk of high cuff pressure, while the secondary outcomes were increases in cuff pressure following EDI. Difference between adults and children was investigated with subgroup analysis. There were ten eligible studies (observation study, n = 9, randomized controlled study, n = 1) involving a total of 468 participants. EDI notably increased the risk of high cuff pressure (n = 7, risk ratio: 12.82, 95% confidence interval: 4.9 to 33.52, subgroup analysis: p = 0.008). There were significant elevations in cuff pressure in adults and children both during (13.42 and 7.88 cmH2O, respectively, subgroup analysis: p = 0.15) and after (10.09 and 3.99 cmH2O, respectively, subgroup analysis: p = 0.0003) EDI. Our results revealed an over 12-fold increase in the risk of high endotracheal tube cuff pressure in patients, especially adults, receiving EDI under endotracheal anesthesia. There were significant increases in both adults and children despite a higher increase in the former after device insertion.

Endotracheal Tube Cuff Inflation Pressure awareness and response to education among anesthesia technicians

Objective: Cuffed endotracheal tubes are used to ensure ventilator compliance and prevent pulmonary aspiration in mechanically ventilated patients. At cuff pressures greater than 40 cmH2O, mucosal irritation, ulceration, hemorrhage, tracheal stenosis, and tracheoesophageal fistula can occur due to increased perfusion pressure of the tracheal mucosa and submucosa. In this study, we compare the awareness of cuff pressure among anesthesia technicians working in the operating room. Materials and Methods: All anesthesia technicians received a seminar on cuff pressure. An attempt was made to determine the difference between cuff pressures measured before and after the seminar. Results: A positive correlation was found when the cuff pressure measurement was compared with the first measurement after the training (Cor. Coef.= 0.376). At the first measurement, the mean cuff pressure was 82 cmH20, the lowest pressure was 27, and the highest was 223. At the measurement after completion of the training, the mean pressure was 50, the lowest pressure was 26, and the highest pressure was 105. The difference between the two measurements was statistically significant (p=0.000). Before training, only four technicians (7.40%) inflated below the recommended confidence interval (30 cm H2O), while the remaining 50 technicians (92.6%) inflated above this limit. After training, 11 technicians could inflate below the confidence interval. A statistically significant increase was observed (p &lt; 0.05). Conclusion: Measuring the cuff pressure of the endotracheal tube was essential to avoid possible complications. Educational seminars on this topic and the provision of cuff meters can avoid these problems.

The Comparison of Inflation of Cuff with 1% Propofol, 4% Lignocaine, or 0.9% Saline on Laryngotracheal Morbidity.

While administering general anesthesia requiring endotracheal intubation, it is a common practice to inflate the cuff with air. Continuous pressure exerted by cuff on mucosa may lead to postoperative complaints such as sore throat, cough, and dysphagia, which are very disturbing to the patient. Hence, we hypothesized that inflation of cuff with propofol may reduce the incidence of these complications as a result of cushioning effect as well as non-diffusion of nitrous oxide into it. Our aim was to compare the effects of inflation of endotracheal tube cuff with 0.9% saline, 4% lignocaine, and 1% propofol on the incidence of postoperative morbidity in terms of cough, sore throat, dysphonia, and dysphagia with general anesthesia using nitrous oxide. Patients scheduled for elective surgery under general anesthesia were randomly allocated into four equal groups of thirty each as per cuff inflation media: air (Group A), 0.9% saline (Group S), 4% lidocaine (Group L), and 1% propofol (Group P). The incidence of cough was noted at 15, 30 and 60 min after extubating. The occurrence and severity of postoperative sore throat (POST) was evaluated at 2, 6, and 24 h after extubating. The incidence of cough was maximum in Group A and minimum in Group P (P < 0.05). The occurrence of POST was highest in Group A, followed by Group S and Group L, and least in Group P. The hemodynamic parameters were comparable with no statistical difference in all the four groups (P < 0.05). The intracuff 1% propofol is superior to 4% xylocaine and normal saline in the prevention of cough and sore throat postoperatively, whereas inflation of cuff with air leads to maximum incidence of these complications.

Comparative evaluation of three methods of endotracheal tube cuff inflation for adequacy of seal.

Intubation with cuffed endotracheal tube (ETT) is common in operation rooms, critical care, and emergency rooms. The pressure exerted by the cuff on the tracheal mucosa can lead to a reduction in blood flow to the tracheal wall and result in mucosal ischemia. There are many methods for ETT cuff inflation. Aim of the study was to compare the cuff pressures and volumes between the three methods of ETT cuff inflation. One hundred and twenty patients were randomized into three groups: Group SG (stethescope guided), group AL (audible leak), and group P (palpation). In group SG, the cuff was inflated by auscultating with the bell of the stethoscope over the thyroid cartilage for leak around cuff. In group AL, the cuff was inflated by listening for an audible leak around the cuff with observer's ear 5 cm away from the mouth of the patient. In group P, the cuff was inflated by palpating for a leak over the cricoid and trachea. The adequacy of the cuff seal was compared between the groups by assessing the volumes of additional air needed to stop the leak around the cuff as confirmed by supraglottic capnometry. The initial volumes needed to inflate the cuff were significantly more in the stethoscope (SG) and hearing (AL) groups than in the palpation (P) group (SG = 5.1 ± 1.4 ml, AL = 4.6 ± 1.6 ml, P = 3.1 ± 0.9 ml; SG and AL vs. P, P < 0.001). Additional cuff volumes required to achieve zero leak around cuff by supraglottic capnometry were 0.85 ± 1 ml in group SG, 1.3 ± 1.1 ml in group AL, and 2.237 ± 0.8 ml in group P (SG vs. P and AL vs. P; P < 0.001). Out of the auscultation-guided, audible leak-guided, and palpation-guided methods of ETT cuff inflation, the auscultation-guided and audible leak-guided methods achieve significantly better tracheal seal than the palpation-guided method.

Comparison of saline versus air for identifying endotracheal intubation with ultrasound

IntroductionAfter intubation has been performed, it is important to rapidly confirm the correct location of the endotracheal tube (ETT). Multiple techniques have been described, each with different limitations. Ultrasound has been increasingly recognized as an alternate modality for identifying the ETT location. However, it can be challenging to visualize the air-filled ETT cuff. Saline insufflation of the ETT cuff has been suggested to improve visualization of the ETT but data are limited. Our study sought to compare the diagnostic accuracy of air versus saline ETT cuff inflation on the diagnostic accuracy of intubation. MethodsThis was a randomized trial comparing air versus saline cuff inflation using a cadaver model. Adult cadavers were intubated in a random sequence with respect to both the location of intubation (i.e., tracheal vs esophageal) and air versus saline. Blinded sonographers assessed the location of the ETT using the static technique. Outcomes included accuracy of sonographer identification, time to identification, and operator confidence. Results480 total assessments were performed. When using air, ultrasound was 95.8% sensitive (95% CI 90.5% to 98.6%) and 100% specific (95% CI 97.0% to 100%) with a mean time to confirmation of 8.5 s (95% CI 7.6 s to 9.4 s) and a mean operator confidence of 4.32/5.0 (95% CI 4.21 to 4.42). When using saline, ultrasound was 100% sensitive (95% CI 97.0% to 100%) and 100% specific (95% CI 97.0% to 100%) with a mean time to confirmation of 6.3 s (95% CI 5.9 s to 6.8 s) and a mean operator confidence of 4.52/5.0 (95% CI 4.44 to 4.60). ConclusionThere was no statistically significant difference between air versus saline for intubation confirmation. However, saline was associated with fewer false negatives. Additionally, time to confirmation was faster and operator confidence was higher with the saline group. Further studies should determine if the outcomes would change with more novice sonographers or in specific patient populations.

A randomised controlled trial of intracuff lidocaine and alkalised lidocaine for sedation and analgesia requirements in mechanically ventilated patients.

Background Airway irritation caused by prolonged inflation of endotracheal tube (ETT) cuff results in post-intubation morbidities. Objectives We aimed to study intracuff lidocaine and alkalised lidocaine on sedation or analgesia requirements of patients undergoing mechanical ventilation in the intensive care unit (ICU). The primary outcome was to calculate the total dose of propofol and fentanyl required to obtund the unwanted airway and circulatory reflexes. Secondary outcomes were to determine the frequency and severity of cough and haemodynamic parameters. Methods It was a double-blinded, randomised controlled study in the ICU after emergency laparotomy, in patients aged 20 - 55 years, and classified as American Society of Anesthesiologists (ASA) classes 1E and 2E with tube in situ. Exclusion criteria were patients with body mass index >30 kg/m² , haemodynamic instability, requiring positive end-expiratory pressure ≥7 cm H2O, and a history of chronic obstructive pulmonary disease. After ethics clearance and written consent, patients were randomly assigned into two groups (36 in each), Group L (ETT cuff inflated with lidocaine 2%) and Group AL (cuff inflated with a mixture of lidocaine 2% and sodium bicarbonate 1:1). Results Mean dose of propofol consumed in Group AL was significantly less than that in Group L (p<0.001). The mean standard deviation (SD) fentanyl utilisation in Group AL was 1 323.61 (187.27) µg, and that in Group L was 1433.09 (42.58) µg (p=0.040). Group L patients had a significantly higher incidence of cough than those in Group AL (p=0.01). There was no significant difference in the mean arterial pressure (p=0.22), although heart rate was significantly higher in Group L (p<0.001). Conclusion Alkalised lidocaine reduces the requirement of sedation, analgesia, and the incidence of cough in intubated patients maintaining haemodynamic stability when compared with lidocaine. Contributions of the study Alkalised lidocaine when used in endotracheal tube cuff inflation reduces the need for sedation and analgesia in mechanically-ventilated patients, and improves haemodynamic stability.

Endotracheal intubation of the dog and cat

Endotracheal intubation is performed for general anaesthesia, critical care, and emergency situations. As the veterinary surgeon often performs this procedure, it may be under-developed, or minimally practiced by veterinary nurses (VNs) despite being legal to perform in several countries. As an emergency skill, and as the role of VNs grows, this article aims to act as a resource for VNs wanting to learn to perform endotracheal intubation correctly. This article will only review the purpose of endotracheal intubation, the relevant anatomy and physiology, equipment, techniques, and troubleshooting. It will not offer a detailed comparison of endotracheal intubation versus laryngeal mask airway, nor will it discuss the technique for endotracheal tube cuff inflation as the full scope of published data, experiences and opinions could not be given due justice: moreover, this is an area of the skill VNs are already familiar with. Maintenance of the in-situ tube and extubation are also excluded and all of these subjects warrant further discussion in a separate article.

COMPARISON OF “JUST SEAL” VS “STETHOSCOPE GUIDED” CUFF INFLATION METHOD OF ENDOTRACHEAL TUBE CUFF FOR REDUCTION OF POST OPERATIVE SORE THROAT

Objective: To compare the efficacy of “Just seal” method of endotracheal tube cuff inflation versus “stethoscope guided”method for reduction of frequency of post operative sore throat.&#x0D; Study Design: Prospective observation study.&#x0D; Place and Duration of study: This study was conducted in Main operation theatre, CMH Kohat from 1st September 2018 to 30th November 2018.&#x0D; Patients and methods: 44 patients divided in two groups of 22 each were made, Group JS and Group SG. Inj Propofol and atracurium was used for induction of general anaesthesia, and Inj Nalbuphine was used as analgesic. Endotracheal intubation with 7.5 internal diameter ETT, was done after 3 minutes of injecting atracurium. In group JS, ETT cuff was inflated gradually till no leakage was heard. In group SG, ETT cuff was inflated slowly and stethoscope bell was placed over thyroid lamina till harsh sounds stopped. Age, volume used to inflate cuff, cuff pressure generated and complain of sore throat 02 hours after extubation were noted.&#x0D; Results: Mean age was 30.22 ±4.7 years and 30.13± 4.2 years for Group JS and SG respectively (p=0.946). Mean volume used was 6.81±0.41 ml and 4.95±0.29 ml for Group JS and SG respectively (p=0.000). Mean pressure generated was 34.90±4.48 cmH2O and 28.91±2.37 cmH2O (p=0.000). Frequency of Post operative sore throat was 54.55% (12/22) in JS group and 18.18 % (4/22) in SG group (p= 0.012).&#x0D; Conclusion: Stethoscope guided technique for inflation of ETT cuff is more effective in reducing frequency of post operative sore throat.

Effect of Air versus 1% Lignocaine used for Endotracheal Tube Cuff Inflation on Laryngotracheal Morbidity after Laparoscopic Surgery- A Randomised Clinical Study

Introduction: Endotracheal intubation in general anaesthesia is associated with post intubation morbidity due to prolonged inflation of Endotracheal Tube (ETT) cuff with air. During laparoscopic surgery their incidence increases further. Lignocaine is likely to diffuse through ETT cuff when instilled into it. As a result, it decreases coughing, sore throat and hoarseness by reducing local irritation and inflammation of the airway. Aim: To compare the effect of air and 1% lignocaine used for ETT cuff inflation on postoperative sore throat, hoarseness of voice and coughing in patients undergoing laparoscopic surgeries. Materials and Methods: This double-blinded randomised clinical study was conducted at Shree Krishna Hospital, Karamsad, Gujarat, India, between September 2021 to March 2022. Total of 54 patients were randomly divided into two groups with 27 in each; group A (air) and group X (1% lignocaine= 2% lignocaine and equal volume of normal saline). Postextubation patients were assessed for Postoperative Sore Throat (POST), hoarseness and coughing at 2 hours and 18-24 hours. Fisher’s-exact test was used to find association between categorical variables in both the groups. A p-value &lt;0.05 was considered statistically significant. Results: The mean age in group A was 46.04±10.26 years, and in group X was 48.59±10.92 years. At 2 hours, in group X 11% (n=3) of patients had postoperative sore throat as compared to group A where nine patients (33%) reported postoperative sore throat (p-value=0.099). Group X showed a significantly reduced incidence of postoperative sore throat at 18-24 hours, hoarseness of voice, coughing at 2 hours and at 18-24 hours as compared to group A. Conclusion: The use of 1% lignocaine for ETT cuff inflation in laparoscopic surgeries was associated with reduced incidence of postoperative sore throat, hoarseness of voice and coughing as compared to air.

Intra-tracheal multiplexed sensing of contact pressure and perfusion.

Incorrect endotracheal tube (ETT) cuff inflation pressure causes significant problems for intubated patients. The technical development and first in vivo use of a smart ETT for measurements at the cuff-trachea interface during mechanical ventilation are described. The intra-tracheal multiplexed sensing (iTraXS) ETT contains integrated optical fibre sensors to measure contact pressure and blood perfusion. The device is tested during mechanical ventilation in a porcine model (N=6). For contact pressure, signals were obtained in all 30 measurements. For perfusion, data could be obtained in all 33 measurements. In the 3 cases where the cuff was inflated to an artificially high-level, blood occlusion is observed.

A comparison of intubating conditions for nasotracheal intubation with standard direct Macintosh laryngoscope versus C-MAC® video laryngoscope employing cuff inflation technique in adult patients.

Background and Aims:While performing laryngoscopy during nasotracheal intubation (NTI), the tip of the advancing endotracheal tube (ETT) generally lies along the posterior pharyngeal wall. The inflation of the ETT cuff brings it anterior towards the glottis. The present study was planned to compare the intubating conditions for NTI with standard direct Macintosh laryngoscope versus C-MAC® video laryngoscope (VL) employing ETT cuff inflation technique.Methods:This prospective randomised study was carried out on 50 patients, American Society of Anesthesiologists physical status I–II, age 18–60 years of either sex with an indication for NTI under general anaesthesia. They were randomly divided into two groups: group VL (n = 25): C-MAC® VL and group ML (n = 25): Macintosh laryngoscope. The primary outcome was to compare the total duration of NTI (T), while the secondary outcomes were to compare the need for cuff inflation or assistance with Magill forceps for successful NTI, the total number of attempts to achieve successful NTI, haemodynamic effects and complications.Results:T was significantly higher in group ML than group VL (P < 0.001). The intubation was successful with cuff inflation in all the patients in group VL, however, six patients of group ML required assistance with Magill forceps (P = 0.022). The haemodynamic parameters were all significantly higher at 3 min in group ML in comparison to group VL.Conclusion:The cuff inflation technique when used along with C-MAC® VL had more success rate, required lesser time and had minimal postoperative complications in comparison to the Macintosh laryngoscope.

Assessing the accuracy of ultrasound measurements of tracheal diameter: an in vitro experimental study

BackgroundRecent studies indicate that ultrasound can detect changes in tracheal diameter during endotracheal tube (ETT) cuff inflation. We sought to assess the accuracy of ultrasound measurement of tracheal diameter, and to determine the relationship between tracheal wall pressure (TWP), cuff inflation volume (CIV), and the degree of tracheal deformation.MethodsOur study comprised two parts: the first included 45 porcine tracheas, the second 41 porcine tracheas. Each trachea was intubated with a cuffed ETT, which was connected to an injector and the manometer via a three-way tap. The cuff was inflated and the cuff pressure recorded before and after intubation. The tracheal diameter was measured using ultrasound. This included three separate measurements: outer transverse diameter (OTD), internal transverse diameter (ITD), and anterior tracheal wall thicknesses (ATWT). A precision electronic Vernier caliper was also used to measure tracheal diameter. We calculated TWP and the percentage change of tracheal diameter. The Bland–Altman method, linear regression, and locally weighted regression (LOESS) were used to analyze the data.ResultsThere were strong correlation and agreement for OTD (r = 0.97, P < 0.001) and ITD (r = 0.90, P < 0.001) as measured by ultrasound and by precision electronic Vernier caliper, but a poor correlation for ATWT (r = 0.58, P < 0.001). There was a strong correlation between the percentage change of OTD (OTD%, r = 0.75, P < 0.001) and CIV, the percentage change of ITD (ITD%, r = 0.77, P < 0.001) and CIV, TWP (r = 0.75, P < 0.001) and CIV. And a strong correlation was also found between TWP and OTD% (r = 0.84, P < 0.001), TWP and ITD% (r = 0.84, P < 0.001).ConclusionsUse of ultrasound to measure OTD and ITD is accurate, but is less accurate for ATWT. There is a close correlation between OTD%, ITD%, CIV and TWP.