Increase In Cuff Pressure Research Articles

Effect of different patient positions on endotracheal tube cuff pressure in patients undergoing urological procedures: a prospective study.

The endotracheal tube (ETT) contains a cuff that is placed in the trachea to prevent gas leakage and aspiration of secretions and gastric contents. However, patient positioning after intubation may cause ETT displacement and changes in cuff pressure. Evaluate the effect of different patient positions on ETT cuff pressure in patients undergoing urological procedures in supine, prone, lateral flank, and lithotomy positions. Prospective and observational study. A university hospital in Turkey. Patients who underwent surgeries under general anesthesia in different patient positions were involved. After intubation (T0), the cuff pressure was checked with a manometer and adjusted to 25 cmH2O and continuously monitored. The cuff pressure was checked before (T1) and after achieving the final position (T2) and then at 5, (T3), 10, (T4), 15 minutes (T5) of the position, at the end of the procedure (T6) and before extubation (T7). At postoperative 2nd and 12th hours, the patients were interviewed for sore throat, hoarseness, and cough. The effect of different patient positions on the ETT cuff pressure. 200 patients. The cuff pressure increased significantly at T2 in the lithotomy, lateral flank, and prone groups (P<.001 each). The highest increase in cuff pressure occurred in the prone group (34.3 [7.5] cmH2O). Over time, the cuff pressure decreased in all groups during surgery. Postoperative complications at the 2nd postoperative hour were similar in all groups; however, the mean cuff pressure was significantly higher in the patients with postoperative sore throat or cough (sore throat: P=.003; cough: P=.047). ETT cuff pressures are affected by different patient positioning; therefore, regular recording and adjustment of cuff pressure are necessary for patient safety. We used ETT of a single manufacturer. Therefore, our findings may not be applicable to other types of ETT.

Battle of the Gases: How Air and Nitrous Oxide Affect Endotracheal Tube Cuff Pressure During General Anesthesia.

Background Endotracheal tube (ETT) cuff pressure changes during general anesthesia. Endotracheal cuff pressure ideally should be maintained between 20 and 30 cm of H2O. Cuff pressure of less than 25 cm of H2O increases the chances of aspiration while pressure of more than 40 cm of H2O causes tracheal mucosa damage. The study aimed to monitor and compare variations of endotracheal cuff pressure during general anesthesia with oxygen-air or oxygen-nitrous oxide. Methods This prospective, randomized, double-blinded, observational study was conducted on 40 patients. After approval from the institutional ethics subcommittee, 40 patients of either gender, aged 18-60 years, belonging to ASA grades I and II, who were undergoing elective surgery under general anesthesia, were enrolled in this study. The patients were randomly divided into two groups, with 20 in each group. In Group A, oxygen-air and Group N, oxygen-nitrous oxide was used as a gaseous mixture in general anesthesia with ETT. The ETT cuff pressure was recorded with the help of a cuff manometer at intervals of five, 10, 20, 30, 40, 50, 60, 70, 80, and 90 minutes after intubation. If pressure was more than 40 cm of H2O, it was reduced to 25-30 cm of H2O. Data were collected and analyzed using methods described in Primer of Biostatistics by Stanton A. Glantz. Quantitative data were analyzed using the Student's t-test. Qualitative data were analyzed using the chi-square test. Results An increase in cuff pressure was noted more in Group N as compared to Group A. The pressure in the endotracheal cuff started to gradually increase after 30-40 minutes in Group N after intubation, while in Group A, there was no significant increase. The average number of times the cuff deflated was 0.2 ± 0.41 in Group A and 1.55 ± 0.51 in Group N, which was highly significant. Conclusion Changes in endotracheal cuff pressure were observed when using different gas mixtures for inflation. Specifically, cuff pressure increased with oxygen and nitrous oxide compared to oxygen with air. This suggests that anesthetic gas composition can impact cuff pressure, potentially affecting tracheal mucosal perfusion and patient safety. Therefore, regular monitoring and adjustment of cuff pressure is crucial, especially when using nitrous oxide, to prevent complications and ensure optimal patient care.

Effect of cuff inflation with lidocaine, saline, and air on tracheal tube cuff pressure during laparoscopic resection of colorectal neoplasms: a randomized clinical trial

BackgroundTracheal tube cuff pressure will increase after pneumoperitoneum when the cuff is inflated with air, high pressure can cause tracheal mucosal damage. This prospective trial aimed to assess if inflating with normal saline or lidocaine can prevent increase of tracheal tube cuff pressure and tracheal mucosal damage in laparoscopic surgeries with general anesthesia. Whether changes of tracheal tube cuff transverse diameter (CD) can predict changes of tracheal tube cuff pressure.MethodsNinety patients scheduled for laparoscopic resection of colorectal neoplasms under general anesthesia were randomly assigned to groups air (A), saline (S) or lidocaine (L). Endotracheal tube cuff was inflated with room-temperature air in group A (n = 30), normal saline in group S (n = 30), 2% lidocaine hydrochloride injection in group L (n = 30). After intubation, tracheal tube cuff pressure was monitored by a calibrated pressure transducers, cuff pressure was adjusted to 25 cmH2O (T0.5). Tracheal tube cuff pressure at 15 min after pneumoperitoneum (T1) and 15 min after exsufflation (T2) were accessed. CD were measured by ultrasound at T0.5 and T1, the ability of ΔCD (T1-0.5) to predict cuff pressure was accessed. Tracheal mucous injury at the end of surgery were also recorded.ResultsTracheal tube cuff pressure had no significant difference among the three groups at T1 and T2. ΔCD had prediction value (AUC: 0.92 [95% CI: 0.81–1.02]; sensitivity: 0.99; specificity: 0.82) for cuff pressure. Tracheal mucous injury at the end of surgery were 0 (0, 1.0) in group A, 0 (0, 1.0) in group S, 0 (0, 0) in group L (p = 0.02, group L was lower than group A and S, p = 0.03 and p = 0.04).ConclusionsCompared to inflation with air, normal saline and 2% lidocaine cannot ameliorate the increase of tracheal tube cuff pressure during the pneumoperitoneum period under general anesthesia, but lidocaine can decrease postoperative tracheal mucosa injury. ΔCD measured by ultrasound is a predictor for changes of tracheal tube cuff pressure.Trial registrationChinese Clinical Trial Registry, identifier: ChiCTR2100054089, Date: 08/12/2021.

Inhalation anesthesia in the cat: Development of cuff pressure when using nitrous oxide

During inhalation anesthesia with nitrous oxide in oxygen the pressure in the cuff of the endotracheal tube may increase due to diffusion of nitrous oxide into the cuff. The aim of the study was to investigate the development of cuff pressure during nitrous oxide anesthesia under clinical conditions in feline patients and to identify possible influencing factors such as tube size and gas flow rate. The prospective study included cats scheduled for inhalation anesthesia with nitrous oxide for a minimum duration of 60 minutes at the Department for Small Animals of the University of Leipzig. Cuff pressure was adjusted with a cuff manometer and its development was recorded. In total, the cuff pressure values of 24 cats were recorded. Animals were allocated into groups by tube size (ID 4.0 mm and ID 4.5 mm) and by fresh gas flow rate: low flow rate (0.6 l/min) and high flow rate (3 l/min). During anesthesia, cuff pressure increased over time, with statistical significance occurring from 45 minutes onwards in comparison to the initial cuff pressure (p=0.005). After 60 minutes, there was a mean cuff pressure increase of 3 cmH2O. Despite this moderate mean increase, highly variable pressure values up to 48 cmH2O in individual animals were recorded. No cat reached the termination criterion of 60 cmH2O cuff pressure. Effects of tube size (p=0.63) and flow rate (p=0.334) on the cuff pressure were not evident. After a period of 45 minutes of nitrous oxide administration, a significant increase in cuff pressure occurs in the cat. However, tube size and total gas flow rate do not seem to influence the cuff pressure development. When using nitrous oxide during inhalation anesthesia, regular cuff pressure evaluation and correction are necessary and hence recommended in feline patients. As individual pressure changes may be highly variable, no fixed recommendations for optimal management are possible.

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.

A Comparative Study of Cuff Pressure Changes of Endotracheal Tube with the Use of Air Versus Nitrous Oxide in the Anaesthetic Gas Mixture During Laparoscopic Surgery.

Objective:Cuffed endotracheal tube remains the standard of care during laparoscopic surgeries. Nitrous oxide is widely used as a carrier gas in anaesthesia practice. Cuff pressure greater than 30 cm H2O impairs tracheal mucosal perfusion leading to necrosis. This study aimed to compare the endotracheal tube cuff pressure while using air versus nitrous oxide in the anaesthetic gas mixture during laparoscopic surgeries.Methods:Sixty patients aged 18-70 years undergoing laparoscopic surgery were randomized into 2 groups of 30 each. Group 1 patients received air and oxygen in the anaesthetic gas mixture and group 2 patients received nitrous oxide and oxygen. Cuff pressure changes were measured throughout the surgery and perioperative hemodynamic parameters were recorded. The incidence and severity of postoperative sore throat were also evaluated postoperatively for 24 hours.Results:The increase in cuff pressure was more in the group using nitrous oxide (40.80 ± 8.78 cm H2O) when compared to the group using air (26.93 ± 2.69 cm H2O) (P < .001). Trendelenburg position was associated with a significant increase in cuff pressure when compared to other positions. The incidence and severity of postoperative sore throat were more at 2 hours (P = .0099) and 4 hours (P = .0105) postoperatively in the group using nitrous oxide. The hemodynamic parameters were comparable between the 2 groups.Conclusion:The use of nitrous oxide in the anaesthetic gas mixture causes an increase in endotracheal tube cuff pressure and increased severity of postoperative sore throat during laparoscopic surgeries.

Endotracheal Tube Cuff Pressure Changes with Pneumoperitoneum and Steep Head Down Position in Patients Undergoing Robotic Urogynecological Surgeries – A Prospective Observational Study

Background: The abdominal insufflation in the laparoscopic surgery has been reported to result in an increase in endotracheal tube (ETT) cuff pressure (Pcuff). However, the effect of Trendelenburg, lithotomy and pneumoperitoneum on the ETT Pcuff in robotic urogynaecology surgeries are not well established. Aim: Analyse the changes in ETT cuff pressure during robotic urognaecological surgery. Primary Objective: 1. The changes in ETT cuff pressure after creation of pneumoperitoneum. 2. The changes in ETT cuff pressure after change in position of the patient. Secondary Objectives: 1. To correlate the changes in ETT cuff pressure with airway pressure. 2. To correlate the changes in ETT cuff pressure with BMI. Methods: Sixty patients undergoing elective robotic urogynaecology surgeries were enrolled in the study. ETT Pcuff during different time points was measured and analysed. Also, the change in ETT Pcuff was correlated with the airway pressure (Paw). Results: The difference in ETT Pcuff, before and after lithotomy, pneumoperitoneum and the Trendelenburg position were 1.1 ± 0.7 cmH2O, 4.6 ± 1.0 cmH2O and 1.8 ± 0.8 cmH2O respectively and were statistically significant (probability: P &lt; 0.05). Results obtained after reversing patient position from Trendelenburg position to supine, abdominal deflation and from lithotomy to supine respectively were -2.2 ± 1.4 cmH2O, -4.1 ± 1.0 cmH2O and -0.4 ± 0.8 cmH2O respectively (P &lt; 0.05). The Karl Pearson coefficient of correlation (r) between Pcuff and Paw after lithotomy, pneumoperitoneum, and Trendelenburg position respectively were 0.606, 0.661 and 0.309. Freidman's nonparametric repeated-measures analysis of variance (ANOVA) was used to analyze differences between related Pcuff values over different time points. Overall P value was significant (P &lt; 0.00001). Conclusion: An increase in ETT cuff pressure is seen in robotic laparoscopic surgeries after abdominal insufflation, Trendelenburg position and lithotomy position.

A prospective observational study on changes in endo-tracheal tube cuff pressure and its correlation with airway pressures during various stages of robotic pelvic surgeries.

Background and Aims:Robotic surgeries often require a relatively long duration of pneumo-peritoneum and trendelenburg position which may accentuate changes in endo-tracheal tube (ETT) cuff pressure leading to pressure related complications. The aim of this study was to analyze changes in ETT cuff pressures during various stages of pneumo-peritoneum and surgical positioning and its correlation with airway pressure changes.Material and Methods:A prospective observational study was planned after approval of institutional review board on 60 patients undergoing elective robotic pelvic surgery requiring head down position. Baseline cuff pressure was adjusted to 25 cm H2O. ETT cuff pressure, peak airway pressure and end tidal CO2 (ETCO2) was measured at various time intervals before and after pneumo-peritoneum and head down. Ventilatory parameters were kept fixed after baseline setting. Those requiring any change were excluded. Pearson’s coefficient was used for correlation and ANOVA for trend of parameters at different time intervals (P value <0.05 was considered significant).Results:Baseline cuff pressure after manual inflation was 46.2 ± 17.4 cm H2O. Significant correlation was observed between change in cuff pressure and increase in peak airway pressure at the end of the surgery (r = 0.4, P < 0.05). Serial measurements of ETT cuff pressure, peak airway pressure and ETCO2 were significantly increased compared to baseline (P < 0.05).Conclusion:Significant increases in ETT cuff pressure may be seen in robotic surgeries, with a positive correlation between change in cuff pressure and increase in airway pressures. Objective adjusted measurement of cuff pressure and airway pressures is recommended for such surgeries.

ЗМІНИ ГЕМОДИНАМІКИ ПРИ ДІЇ ОБ’ЄМНОГО ПНЕВМОПРЕСИНГУ НА ЛІМФАТИЧНУ СИСТЕМУ

Introduction.High prevalence of cardiovascular diseases, [1] implies continuous improvement of noninvasive physical techniques particularly perfectioning of compression therapy techniques, [3]. Intermittent pneumatic compression (IPC)widely used thought multipurpose physical rehabilitation in vascular surgery, dermatologic surgery, and sport medicine. Compressiontherapy (CT) is an established treatment method with very low rate of complicationsin research various facets of vascular and skeletal muscle physiology, [4].Purpose.The study was aimed to evaluate of intermittent pneumatic compression hemodynamic effects on the lower extremities and identify the effectiveness external pressure parameter of value 40 mm Hg.Methods.The study was included healthy 25 volunteers, 17+ years of age. The research shows that the mean physiological pressure in the superficial lymphatic vessel in the lower limb is 10–12 mmHg, then the external pressure (on skin) is 30–40 mmHg. Therefore, only greater external pressure can stimulate lymph drainage. In our research, used average pressures of 40 mmHg, and the procedure time limit at 20 minutes were applied. Outcome was considered succeed if blood pressure was dropped during and after procedure by increasing the expelled blood volume flow during a given period. To investigate the hemodynamic parameters after IPC, impedance cardio-vasography (ICVG) was implied.Results.A summary of the 20-minute testing with IPC of 40 mm hg pressure indicators in the chambers led to the following outcomes. Indications diastolic pressure significant were decrease for about 5-10 min of the procedure (p˂0,05) and by 15-20 minutes in recovery period, (p˂0,01). This phenomen may be attributted in changing the physiological milieu of the lymphatic system through compression application, a mechanism necessary to promote fluid uptake and alleviate limb swelling. However, there is evidence to suggest tissue fluid transport is not associated with transport of macromolecules (i.e., protein) from the interstitial tissue, [12,13,14]. Data suggest that the reactivity of blood pressure under the action IPC on the lower extremities with an intensity of 40 mm Hg maximizes endothelial shear stress. Rapid inflation stimulates the endothelium to release nitric oxide, which in turn inhibits platelet aggregation and platelet and monocyte adhesion. This indicates that the shear stress produced by IPC induces changes in endothelial cell function producing adaptation of blood vessels, resulting in clinical effects that can be measured, including improved arterial perfusion. Would be assumed that, depending on the compression parameters, the procedure time also depends if it was supposed to achieve an effect on the central hemodynamics. In case study, the recommended is that with an increase in cuff pressure, the recommended time should within 20 minutes or less. And vice versa - to achieve a lesser effect on central hemodynamics - the compression in the cuffs should be reduced to values less than 40 mm Hg and, accordingly, the procedure time should be increased.61 ISSN 2076-5835. Вісник Черкаського університету. 2022. No1Originality.To identify the effectiveness external pressure parameter of value 40 mm Hg.Conclusion.Applying IPC devices for hypertension prevention is gradually becoming a standard second-order therapy, particularly for patients with a high risk bleeding. However, a number of questions remain with regard for determining a more accurate time of inflation and deflation in the chambers of IPC devices are required and pressure parameters to its optimal use. The literature overview suggests that IPC improved hematologic and hemodynamic effects, maximizes endothelial shear stress and emptying of venous blood from the lower extremities are likely major contributors.Key words: timing; hemodynamics; lower extremity; intermittent pneumatic compression; cardio-vasography impedance; parameters.

Effect of diffusion of anaesthetic gases on fibre-optic view change of laryngeal mask airway and post-operative laryngo-pharyngeal morbidity in children - A randomised controlled trial.

Background and Aims:The diffusion of nitrous oxide (N2O) into the air-filled cuff of the classic laryngeal mask airway (LMA) may lead to an increase in cuff pressure (CP) and displacement of LMA affecting its performance. This study was conducted to evaluate the change in optimal position of LMA by fibre-optic bronchoscope, the changes in cuff pressure and oropharyngeal leak pressure (OLP), and post-operative laryngo-pharyngeal morbidity during N2O–oxygen (O2) anaesthesia in children.Methods:After ethics committee approval and written informed consent, 84 children, aged 2 to 8 years undergoing lower abdominal surgery using LMA were included. Anaesthesia was induced with sevoflurane and maintained with either 33% O2 in air (Group 1) or with 33% O2 in 67% N2O (Group 2) along with sevoflurane. The position of LMA using fibre-optic bronchoscope, CP and OLP were recorded at 30, 60 and 90 minutes and at the end of surgery. The incidence of post-operative sore throat, hoarseness of voice and dysphagia was assessed for 24 hours.Results:A mild (Grade 1) change in fibre-optic position of LMA was observed in 6 out of 42 children maintained with N2O–O2 anaesthesia. The cuff pressure was higher than baseline in group 2 at all three time points with the maximum at 90 minutes (93.23 ± 14.86 cm H2O vs. 39.78 ± 7.75 cm H2O; P < 0.05). The OLP was comparable between the groups during the initial 60 minutes and then increased in group 2. The incidence of post-operative sore throat was significantly higher in group 2 (P = 0.008).Conclusion:The diffusion of anaesthetic gases into the air-filled cuff does not change the fibre-optic position of the LMA significantly but increases the cuff pressure and incidence of post-operative laryngo-pharyngeal complications in children.

Examination of the frequency of upward and downward fluctuations in the pressure obtained from the cuff pressure-time curve by continuous measurement of endotracheal tube cuff pressure during thyroid surgery: a case series

BackgroundFew studies examined time-to-time changes of cuff pressure of an endotracheal tube during surgery. We retrospectively analyzed the changes of cuff pressure during thyroid surgery and examined its relationships with postoperative airway complications.Case presentationCuff pressure was initially adjusted at 26 cmH2O and continuously measured in 61 patients. The cuff pressure-time curve dynamically fluctuated, and exceeded 30 cmH2O in all patients, whereas decreased to ≤ 20 cmH20 in 42 (69%) patients. Ratio of the period with such an increase and decrease of cuff pressure to the total duration of surgery were 40% (28–66%) and 9% (0–21%), respectively (median, interquartile range). No patients showed symptoms of airway stenosis requiring treatment except one who developed recurrent laryngeal nerve palsy. No patients had lower respiratory tract infection.ConclusionsCuff pressure dynamically fluctuated during thyroid surgery. Preventing an increase as well as decrease of cuff pressure is required.

Endotracheal Tube Intracuff Pressure Changes in Patients Transported by a Helicopter Emergency Medical Service: A Prospective Observational Study

ObjectiveThe pressure within an endotracheal tube cuff is of particular importance in helicopter emergency medical services (HEMS) transport because the unpressurized cabin is subjected to decreases in atmospheric pressure. This can cause the cuff to overinflate and may be associated with clinical complications. We sought to evaluate endotracheal tube cuff pressure changes among intubated patients during HEMS transport. MethodsA prospective observational study was performed including adult patients who were intubated and transported by helicopter between April 2017 and October 2018. Cuff pressures were measured before, during, and after HEMS transport with a commercial manometer. ResultsA total of 208 patients were included. The median maximum flight altitude was 3,000 (interquartile range [IQR], 2,000-5,000) ft. The median initial cuff pressure before takeoff was 35 (IQR, 24-50) cm H2O, which increased to 50 (IQR, 35-70) cm H2O at maximum altitude. A total of 169 (81.3%) patients had a cuff pressure > 30 cm H2O at maximum altitude. There was a moderate correlation between altitude and cuff pressure (r = 0.532, P < .001). ConclusionsCuff pressure increased during HEMS transport, demonstrating the need for routine cuff pressure monitoring during flight. Further research is required to determine if exposure to transient increases in cuff pressure for short durations is clinically significant.

The Effect of Transesophageal Echocardiography Probe Insertion in Endotracheal Tube Cuff Pressure in Adult Cardiac Surgical Patients.

Background and Aims: Insertion of transesophageal echocardiography probe in cardiac surgical patient is a routine practice for surgical planning and decision making. However it may increase the endotracheal tube cuff pressure as it lies adjacent to the posterior wall of trachea. The aim of this study is to evaluate the changes in cuff pressure after insertion of the transesophageal echocardiography probe and after completion of initial manipulation of the transesophageal echocardiography probe during various examinations in adult cardiac surgical patients.&#x0D; Methods: Thirty six patients undergoing elective cardiac surgery requiring Transesophageal Echocardiography (TEE) monitoring were enrolled in the study. After induction of general anesthesia and endotracheal intubation cuff pressure were measured at 3 points of time; just after intubation (T1), after transesophageal probe insertion (T2) and after initial completion of TEE study (T3). The mean increase in cuff pressure at various point of time were compared.&#x0D; Results: The cuff pressure (mean±SD) at T1, T2 and T3 were 24.61±2.72, 30.22±5.61 and 32.25±4.45 cm of H2O respectively.The cuff pressure increased significantly from T1 to T2 (p&lt;0.001) and from T1 to T3 (p&lt;0.001). The cuff pressure was &gt; 30 cm of H2O in 18 (50%) of patients at T3 which was readjusted back to 25-30 cm of H2O by with drawing air from the cuff.&#x0D; Conclusion: Endotracheal tube cuff pressure should be routinely monitored either intermittently or continuously after transesophageal echocardiography probe insertion till it is in situ and pressure should be readjusted to avoid unwanted complications.

Transesophageal echocardiography-associated tracheal microaspiration and ventilator-associated pneumonia in intubated critically ill patients: a multicenter prospective observational study

BackgroundMicroaspiration of gastric and oropharyngeal secretions is the main causative mechanism of ventilator-associated pneumonia (VAP). Transesophageal echocardiography (TEE) is a routine investigation tool in intensive care unit and could enhance microaspiration. This study aimed at evaluating the impact of TEE on microaspiration and VAP in intubated critically ill adult patients.MethodsIt is a four-center prospective observational study. Microaspiration biomarkers (pepsin and salivary amylase) concentrations were quantitatively measured on tracheal aspirates drawn before and after TEE. The primary endpoint was the percentage of patients with TEE-associated microaspiration, defined as: (1) ≥ 50% increase in biomarker concentration between pre-TEE and post-TEE samples, and (2) a significant post-TEE biomarker concentration (> 200 μg/L for pepsin and/or > 1685 IU/L for salivary amylase). Secondary endpoints included the development of VAP within three days after TEE and the evolution of tracheal cuff pressure throughout TEE.ResultsWe enrolled 100 patients (35 females), with a median age of 64 (53–72) years. Of the 74 patients analyzed for biomarkers, 17 (23%) got TEE-associated microaspiration. However, overall, pepsin and salivary amylase levels were not significantly different between before and after TEE, with wide interindividual variability. VAP occurred in 19 patients (19%) within 3 days following TEE. VAP patients had a larger tracheal tube size and endured more attempts of TEE probe introduction than their counterparts but showed similar aspiration biomarker concentrations. TEE induced an increase in tracheal cuff pressure, especially during insertion and removal of the probe.ConclusionsWe could not find any association between TEE-associated microaspiration and the development of VAP during the three days following TEE in intubated critically ill patients. However, our study cannot formally rule out a role for TEE because of the high rate of VAP observed after TEE and the limitations of our methods.

Changes in endotracheal tube cuff pressure during the open and laparoscopic surgery

Endotracheal tube is an airway catheter inserted in the trachea to assure patency of the upper airway. ETT cuff seals the trachea to facilitating positive-pressure ventilation and to prevent aspiration. The cuff pressure of an endotracheal tube depends on various patient-related factors like obesity, old age, environmental circumstances and therapeutic interventions. Physiological changes in laparoscopic surgery under general anesthesia, due to pneumoperitoneum and change in patient position can affect ETT cuff pressure. These changes in ETT cuff pressure can lead to significant peri-operative adverse outcome.To evaluate the changes in ETT cuff pressure between open and laparoscopic cholecystectomy under general anesthesia.80 ASA grade I/II patients, aged 20-50 years, undergoing laparoscopic or open cholecystectomy, under GA were included in this prospective observational study. Patients were divided in two equal sized groups (N=40) for laparoscopic and open cholecystectomy. ETT cuff pressures were recorded with ETT manometer, at 5 min intervals until extubation. Patients were followed 6 hourly, for 24 hours to record any postoperative complications.The changes in hemodynamic parameters were more in laparoscopic surgery than open surgery. Abdominal insufflation in laparoscopic surgery causes significant increase in cuff pressure due to altered thoracic compliance. Change in position, during laparoscopic surgery, also affects endotracheal tube cuff pressure.The pneumo-peritoneum and positional changes during laparoscopic surgery cause significant increase in endotracheal tube cuff pressure and thus associated with an increased incidence of post-operative complications.

Effect of endotracheal tube lubrication on cuff pressure increase during nitrous oxide exposure: a laboratory and prospective randomized controlled trial

BackgroundWe previously demonstrated that lubrication of an endotracheal tube (ETT) cuff with K-Y™ jelly strongly and significantly inhibited the increase in cuff pressure during nitrous oxide (N2O) exposure in vitro. However, in our previous study, we identified critical differences between some influential factors, such as the amount of lubricant retained on the cuff, and studied temperature differences between laboratory and clinical conditions. Therefore, it remained unclear whether this effect holds true in clinical settings.MethodsWe first sought to study how changes in the amount of K-Y™ jelly and temperature influence the inhibitory effects of the lubricant on the increase in N2O-induced cuff pressure in vitro. Furthermore, we aimed to determine whether the application of K-Y™ jelly inhibits the increase in ETT cuff pressure during general anesthesia using N2O in adult patients.ResultsIn the laboratory studies, we found that K-Y™ jelly inhibited the cuff pressure increase dose-dependently when the dose of K-Y™ jelly was varied (P = 0.02), and that such an inhibitory effect decreased with an increase in the studied temperature (P = 0.019). In the clinical study, lubrication with K-Y™ jelly slightly, but significantly, delayed the increase in ETT cuff pressure during general anesthesia with N2O (P = 0.029). However, the inhibitory effect in the clinical settings was smaller than that in vitro.ConclusionsLubrication of the ETT cuff with K-Y™ jelly may delay the increase in cuff pressure during general anaesthesia with N2O. However, the clinical significance of this effect may be limited.Trial registrationUMIN Clinical Trials Registry: UMIN000031377 on March 1, 2019.

The shear modulus of lower-leg muscles correlates to intramuscular pressure

Shear wave elastography (SWE) is emerging as an innovative tool to evaluate muscle properties and function. It has been shown to correlate with both passive and active muscle forces, and is sensitive to physiological processes and pathological conditions. Similarly, intramuscular pressure (IMP) is an important parameter that changes with passive and active muscle contraction, body position, exercise, blood pressure, and several pathologies. Therefore, the objective of this study was to quantify the dependency of shear modulus within the lower-leg muscles on IMP in healthy individuals. Nineteen healthy individuals (age: Mean age ± SD, 23.84 ± 6.64 years) were recruited. Shear modulus was measured using ultrasound SWE on the tibialis anterior (TA) and peroneus longus (PL) muscles using pressure cuff inflation around the thigh at 40 mmHg, 80 mmHg, and 120 mmHg. Changes in IMP were verified using a catheter connected to a blood pressure monitor. It was found that IMP was correlated to TA and PL shear modulus (spearman's rank correlation = 0.99 and 0.99, respectively). Applying a gradual increase of cuff pressure from 0 to 120 mmHg increased the shear modulus of the TA and PL muscles from 15.83 (2.46) kPa to 21.88 (4.33) kPa and from 9.64 (1.97) kPa to 12.88 (5.99) kPa, respectively. These results demonstrate that changes of muscle mechanical properties are dependent on IMP. This observation is important to improve interpretation of ultrasound elastograms and to potentially use it as a biomarker for more accurate diagnosis of pathologies related to increased IMP.

Effect of intracuff alkalinized 2% lidocaine on endotracheal tube cuff pressure and postoperative throat symptoms in anaesthesia maintained by nitrous oxide.

Aim To compare the effects of endotracheal tube cuff inflation media, air, saline and alkalinized 2% lidocaine on increase of cuff pressure (CP) during nitrous oxide maintained anaesthesia and on incidence of postoperative throat symptoms (PTS), and to evaluate the incidence of postoperative throat mucosal injuries (PTMI) depending on cuff inflation medium. Methods Ninety patients who had undergone elective surgery were randomly allocated into 3 equal groups per cuff inflation media: air (group A), saline (group S) and alkalinized 2% lidocaine (group L). The CP was monitored immediately after cuff inflation and further 5, 15, 30, 60 and 90 minutes after intubation. The incidence and intensity of PTS, sore throat, hoarseness, dysphagia and cough were evaluated 2, 6 and 24 hours after extubation. The incidence and intensity of PTMI were evaluated 24 hours after exubation using indirect laryngoscopy examination. Results The highest increase of mean CP was recorded in the group A (18.7±4.9), it was significantly lower (6.4±1.1) in the group S, while it remained stable in the group L (0.7±0.7). All PTS occurred less frequently in the group L: sore throat (p<0.001), hoarseness and dysphagia (p<0.05), but the incidence of cough was not significantly different between the groups. The lowest incidence of PTMI was in the group L (p< 0.001). Conclusion The increase of CP contributed to incidence of PTS. The intracuff alkalinized 2% lidocaine was superior to saline and air in the prevention of an increase of CP and reduction of the PTS incidence. There was a strong correlation between the incidence of PTS and PTMI.

K-Y\u2122 jelly inhibits increase in endotracheal tube cuff pressure during nitrous oxide exposure in vitro

BackgroundThe increase in endotracheal tube cuff pressure due to nitrous oxide diffusion is a well-known risk during general anesthesia using nitrous oxide. We hypothesized that lubricating endotracheal tube cuffs with K-Y™ Jelly might inhibit the increase in cuff pressure that occurs during exposure to nitrous oxide.MethodsWe used two types of endotracheal tube cuffs: one made from ultrathin polyurethane (PU) and another made from conventional polyvinyl chloride (PVC). Using a pediatric trachea model, which consisted of an acrylic cylinder with an internal diameter of 12 mm, we measured changes in the cuff pressure during nitrous oxide exposure in size 5.0-mm internal diameter endotracheal tubes with each type of cuff, with and without lubrication with K-Y™ Jelly.ResultsDuring nitrous oxide exposure, the increase in cuff pressure was significantly lower in the lubricated cuffs than in the non-lubricated cuffs in both types of cuffs (PVC, P < 0.0001; PU, P < 0.0001). However, the cuff compliance in the trachea model was unaffected by lubrication in both types of cuffs.ConclusionsLubrication of endotracheal tube cuffs with K-Y™ Jelly may effectively delay the increase in cuff pressure that occurs during general anesthesia using nitrous oxide.

Comparison of endotracheal tube cuff pressure changes using air versus nitrous oxide in anesthetic gases during laparoscopic abdominal surgeries

The purpose of this study was to compare the endotracheal tube cuff pressure changes during laparoscopic surgeries using air versus nitrous-oxide in anesthetic gas mixture; and to observe the incidences of postoperative sore throat, hoarseness and dysphagia. Total 100 patients scheduled for elective laparoscopic abdominal surgery were allocated into two groups. Group A (n=50) received air while Group N (n=50) received nitrous-oxide in anesthetic gas mixture. After endotracheal intubation, cuff was inflated with air to achieve sealing pressure. Cuff pressure at baseline (sealing pressure), 30min, 60min and 90min was recorded with a manometer. Incidence of sore throat, hoarseness and dysphagia was noted at the time of discharge from post-anesthesia care unit and 24h after extubation. Cuff pressure increased from baseline in both the groups. The increase in cuff pressure in Group N was greater than that in Group A at all time points studied (p<0.001). Within Group A, cuff pressure increased more at 90min than at 30min (p<0.05). Within Group N, increase in cuff pressure was more at each time point (30, 60 and 90min) than its previous time point (p<0.05). The incidence of sore throat in post-anesthesia care unit was higher in Group N than in Group A. Use of nitrous-oxide during laparoscopy increases cuff pressure resulting in increased incidence of postoperative sore throat. Cuff pressure should be monitored routinely during laparoscopy with nitrous-oxide anesthesia.