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.

Comparing adaptations from blood flow restriction exercise training using regulated or unregulated pressure systems: A systematic review and meta-analysis.

OBJECTIVE: No study has examined outcomes derived from blood flow restriction exercise training interventions using regulated compared with unregulated blood flow restriction pressure systems. Therefore, we used a systematic review and meta-analyses to compare the chronic adaptations to blood flow restriction exercise training achieved with regulated and unregulated blood flow restriction pressure systems. DATA SOURCES: The electronic database search included using the tool EBSCOhost and other online database search engines. The search included Medline, SPORTDiscus, CINAHL, Embase and SpringerLink. METHODS: Included studies utilised chronic blood flow restriction exercise training interventions greater than two weeks duration, where blood flow restriction was applied using a regulated or unregulated blood flow restriction pressure system, and where outcome measures such as muscle strength, muscle size or physical function were measured both pre- and post-training. Studies included in the meta-analyses used an equivalent non-blood flow restriction exercise comparison group. RESULTS: Eighty-one studies were included in the systematic review. Data showed that regulated (n = 47) and unregulated (n = 34) blood flow restriction pressure systems yield similar training adaptations for all outcome measures post-intervention. For muscle strength and muscle size, this was reaffirmed in the included meta-analyses. CONCLUSION: This review indicates that practitioners may achieve comparable training adaptations with blood flow restriction exercise training using either regulated or unregulated blood flow restriction pressure systems. Therefore, additional factors such as device quality, participant comfort and safety, cost and convenience are important factors to consider when deciding on appropriate equipment to use when prescribing blood flow restriction exercise training.

Continuous cuff pressure control on middle-aged and elderly patients undergoing endoscopic submucosal dissection of the esophagus effect of airway injury.

OBJECTIVE: Assessment of the effect of continuous cuff pressure control on airway injury in middle-aged and elderly patients undergoing endoscopic submucosal dissection (ESD). METHOD: A total of 104 eligible middle-aged and elderly patients requiring esophageal ESD from July 2022-September 2023 at the First Affiliated Hospital of Nanchang University were selected and randomly divided into two groups: the group undergoing general anesthesia tracheal intubation with continuous control of cuff pressure after intubation (Group A, n = 51) and the group undergoing general anesthesia tracheal intubation with continuous monitoring without control of cuff pressure (Group B, n = 53). After endotracheal intubation in Group A, under the guidance of an automatic cuff pressure controller, the air was used to inflate the tracheal cuff until the cuff pressure was 25-30cmH2O. The cuff pressure after intubation was recorded, and then the cuff pressure parameters were directly adjusted in the range of 25-30cmH2O until tracheal extubation after the operation. After endotracheal intubation, patients in Group B inflated the tracheal cuff with clinical experience, then monitored and recorded the cuff pressure with a handheld cuff manometer and instructed the cuff not to be loosened after being connected to the handheld cuff manometer-continuous monitoring until the tracheal extubation, but without any cuff pressure regulation. The patients of the two groups performed esophageal ESD. The left recumbent position was taken before the operation, and the cuff's pressure was recorded. Then, insert the gastrointestinal endoscope to find the lesion site and perform appropriate CO2 inflation to display the diseased esophageal wall for surgical operation fully. After determining the location, the cuff pressure of the two groups was recorded when the cuff pressure was stable. After the operation, the upper gastrointestinal endoscope was removed and the cuff pressure of the two groups was recorded. Postoperative airway injury assessment was performed in both groups, and the incidence of sore throat, hoarseness, cough, and blood in sputum was recorded. The incidence of postoperative airway mucosal injury was also observed and recorded in both groups: typical, episodic congestion spots and patchy local congestion. RESULT: The incidence of normal airway mucosa in Group A was higher than that in Group B (P < 0.05). In comparison, the incidence of occasional hyperemia and local plaque congestion in Group A was lower than in Group B (P < 0.05). CONCLUSION: Continuous cuff pressure control during operation can reduce airway injury in patients with esophageal ESD and accelerate their early recovery after the operation.

The knowledge and skills of emergency department registered nursing staff at an academic hospital in South Africa, on endotracheal tube cuff manometry, before and after a training session.

Introduction: Accurate management of endotracheal tube cuff pressure is essential to prevent patient morbidity and mortality. Due to increased length of stay of critically ill patients in emergency departments, it has become an increasingly important skill among Emergency Department nurses. Methods: This prospective longitudinal interventional study was performed among registered nurses at the emergency departments in a Johannesburg Academic Hospital. The study aimed to determine their current knowledge and practical skills on endotracheal tube cuff manometry and assess the effectiveness of a training program. The training program was provided once, in the form of a narrated PowerPoint presentation developed by the researchers and involved theoretical and practical components. The participants' theoretical knowledge and practical skills were measured by using questionnaires and skill assessments. The theoretical and practical scores were compared pre- and post-training. Results: Of the 63 registered nurses employed in the emergency departments, 95 % (60) participated in this study. 86 % reported having never received any formal training on endotracheal tube cuff manometry. Only 38.9 % used cuff manometry as standard practice and only 12.8 % checked it at appropriate 12-hourly intervals. The pre-training median score on theory was 4.5 (IQR=3.0) and improved to 7.0 (IQR=3.0) post-training. The maximum achievable score was 11 with a pre-training average of 41.8 % and post-training of 64.5 % (p = 0.001).The practical pre-training median score was 1.0 (IQR=8.0) and improved to 12.0 (IQR=2.0) post-training. The maximum achievable score was 12 with a pre-training average of 29.1 % and a post-training average of 93.3 % (p = 0.001). Conclusion: This study showed inadequate knowledge and skills on endotracheal cuff pressure manometry among registered nurses in the emergency department. It also correlates with other evidence that supports the need for ongoing training programs. Our training program led to significant improvement among participants in both knowledge and practical skills. This training program was well received by participants and deemed to be practice changing. The recommendation after this study will be for South African emergency units to consider using this study and training material as a guide for annual in-service training.

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

BACKGROUND: Tracheal 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. METHODS: Ninety 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. RESULTS: Tracheal 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). CONCLUSIONS: Compared 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 REGISTRATION: Chinese Clinical Trial Registry, identifier: ChiCTR2100054089, Date: 08/12/2021.

Risk factor evaluation of cuff pressure of >30 cmH2O to stop air leakage during mechanical ventilation: A prospective observational study.

AIM: The commonly recommended endotracheal tube cuff pressure is 20-30 cmH2O. However, some patients require a cuff pressure of >30 cmH2O to prevent air leakage. The study aims to determine the risk factors that contribute to the endotracheal tube cuff pressure of >30 cmH2O to prevent air leakage. DESIGN: A multi-centre prospective observational study. METHODS: Eligible patients undergoing mechanical ventilation in the intensive care unit of three hospitals between March 2020 and July 2022 were included. The endotracheal tube cuff pressure to prevent air leakage was determined using the minimal occlusive volume technique. The patient demographics and clinical information were collected. RESULTS: A total of 284 patients were included. Among these patients, 55 (19.37%) patients required a cuff pressure of >30 cmH2O to prevent air leakage. The multivariate logistic regression results revealed that the surgical operation (odds ratio [OR]: 8.485, 95% confidence interval [CI]: 1.066-67.525, p = 0.043) was inversely associated with the endotracheal tube cuff pressure of >30 cmH2O, while the oral intubation route (OR: 0.127, 95% CI: 0.022-0.750, p = 0.023) and cuff inner diameter minus tracheal area (OR: 0.949, 95% CI: 0.933-0.966, p < 0.001) were negatively associated with the endotracheal tube cuff pressure of >30 cmH2O. Therefore, a significant number of patients require an endotracheal tube cuff pressure of ＞30 cmH2O to prevent air leakage. Several factors, including the surgical operation, intubation route, and difference between the cuff inner diameter and tracheal area at the T3 vertebra, should be considered when determining the appropriate cuff pressure during mechanical ventilation.

Effect of continuous measurement and adjustment of endotracheal tube cuff pressure on postoperative sore throat in patients undergoing gynecological laparoscopic surgery: a randomized controlled trial.

BACKGROUND: Postoperative sore throat (POST) is a common complication following endotracheal tube removal, and effective preventive strategies remain elusive. This trial aimed to determine whether actively regulating intraoperative cuff pressure below the tracheal capillary perfusion pressure threshold could effectively reduce POST incidence in patients undergoing gynecological laparoscopic procedures. METHODS: This single-center, randomized controlled superiority trial allocated 60 patients scheduled for elective gynecological laparoscopic procedures into two groups: one designated for cuff pressure measurement and adjustment (CPMA) group, and a control group where only cuff pressure measurement was conducted without any subsequent adjustments. The primary outcome was POST incidence at rest within 24 h post-extubation. Secondary outcomes included cough, hoarseness, postoperative nausea and vomiting (PONV) incidence, and post-extubation pain severity. RESULTS: The incidence of sore throat at rest within 24 h after extubation in the CPMA group was lower than in the control group, meeting the criteria for statistically significant superiority based on a one-sided test (3.3% vs. 26.7%, P < 0.025). No statistically significant differences were observed in cough, hoarseness, or pain scores within 24 h post-extubation between the two groups. However, the CPMA group had a higher incidence of PONV compared to the control group. Additionally, the control group reported higher sore throat severity scores within 24 h post-extubation. CONCLUSIONS: Continuous monitoring and maintenance of tracheal tube cuff pressure at 18 mmHg were superior to merely monitoring without adjustment, effectively reducing the incidence of POST during quiet within 24 h after tracheal tube removal in gynecological laparoscopic surgery patients. TRIAL REGISTRATION: The study was registered at www.chictr.org.cn (ChiCTR2200064792) on 18/10/2022.

Associations between cognitive test scores and pain tolerance: The Tromsø study.

OBJECTIVES: Previous studies have suggested that experimental pain sensitivity is associated with cognitive function. The aim of this study is to assess this relationship in a large population-based sample. METHODS: We included 5,753 participants (aged 40-84 years) from the seventh wave of the population-based Tromsø Study who had been examined with cognitive tests and experimental pain assessments, and for whom information on covariates were available. Cox regression models were fitted using standardized scores on cognitive tests (12-word immediate recall test, digit symbol coding test, and Mini-Mental State Examination [MMS-E]) as the independent variable and cold pressor or cuff pressure pain tolerance as the dependent variables. Statistical adjustment was made for putative confounders, namely, age, sex, education, smoking, exercise, systolic blood pressure, body mass index, symptoms indicating anxiety or depression, analgesic use, and chronic pain. RESULTS: In multivariate analysis, cold pressor tolerance time was significantly associated with test scores on the 12-word immediate recall test (hazard ratio [HR] 0.93, 95% confidence interval [CI] 0.90-0.97, p < 0.001), the digit symbol coding test (HR 0.94, 95% CI 0.89-0.98, p = 0.004), and the MMS-E (HR 0.93, 95% CI 0.90-0.96 p < 0.001). Tolerance to cuff pressure algometry was significantly associated with 12-word immediate recall (HR 0.94-0.97, p < 0.001) and Digit Symbol Coding test scores (HR 0.93, 95% CI 0.89-0.96, p < 0.001) while there was no significant association with Mini Mental State Examination test score (HR 0.98, 95% CI 0.95-1.00, p = 0.082). CONCLUSION: Lower pain tolerance was associated with poorer performance on cognitive tests.

The effect of different endotracheal tube cuff pressure monitoring systems on postoperative sore throat in patients undergoing tracheal intubation: a randomized clinical trial.

BACKGROUND: Postoperative sore throat (POST) is an unpleasant outcome that can occur as a result of tracheal intubation in adults. Increased pressure from the endotracheal tube (ETT) cuff often leads to local mucosal injury, resulting in sore throat. The purpose of this study was to compare the effect of two different ETT cuff pressure monitoring systems vs. no cuff pressure monitoring on the incidence and severity of POST in adults. METHODS: One hundred and fourteen ASA I-III patients of either gender, aged 18-65 years, and undergoing surgery requiring endotracheal intubation were included in this study. Patients were randomized into three groups: control (C), cuff pressure gauge (G), and automated cuff controller (A). The ETT cuff pressure was not monitored intraoperatively in group C but was monitored using a cuff pressure gauge and an automated cuff controller in groups G and A, respectively. Postoperatively, patients were assessed at 2, 24, and 48 h for the presence and severity of POST, hoarseness and cough. RESULTS: One hundred and eleven patients completed the study. POST occurred in 40.5% of the patients in group G (n = 37) (p = 0.013) and 23.7% of the patients in group A (n = 38) (p < 0.001) within 48 h after surgery, compared to 69.4% in group C (n = 36). There were no significant differences in hoarseness, coughing, and dysphagia across the groups at any time. When comparing groups A and C, individuals in group A exhibited a lower occurrence of significant (grade ≥ 2) POST and hoarseness (10.5% vs. 41.7%, p = 0.002; 26.3% vs. 58.3%, p = 0.005). The incidence of significant cough and dysphagia did not differ substantially across the patient groups within 48 h after surgery. POST scores in group A at 2, 24 h postoperatively were both 0 (0-0), which was significantly lower than those in group C (1 (0-2) at 2 h, p < 0.001 ; 1 (0-1) at 24 h, p = 0.001). POST in group G at 2 h postoperatively was graded as 0 (0-1.5) which was milder than group C (P = 0.024). The severity of hoarseness in group A with scores of 0 (0-2) was superior to that in group C (2 (0-2), p = 0.006) at 2 h postoperatively. CONCLUSIONS: In conclusion, the findings of this study indicated that the occurrence of POST can be reduced by using either the cuff pressure gauge approach or the automated cuff controller method. The automated cuff controller monitoring can potentially decrease the severity of POST and hoarseness. TRIAL REGISTRATION: Chinese Clinical Trial Registry, identifier: ChiCTR2100054089, Date: 08/12/2021.

Relationship of Endotracheal Tube Cuff Pressures with Changes in Body Positions of Critically Ill Patients on Mechanical Ventilation: An Observational Study.

Aims and background: Endotracheal tube cuff pressure (ETCP) is an important factor to determine the development of complications associated with invasive mechanical ventilation. To avoid preventable complications arising out of immobilization, frequent changes in body positioning are necessary. Such variations in body position can affect ETCP in critically ill patients who are on mechanical ventilation. So, our study aimed to assess the effect of changes in body position on ETCP in patients who are on mechanical ventilation. Materials and methods: This prospective observational study included 31 critically ill intubated patients. Each study subject was first placed in a neutral starting position with a 30º head elevation. Then, they were subjected to a sequential change in body position based on the 16 most used positions as part of the critical care unit's (CCUs) daily routine. Endotracheal tube cuff pressure was measured after each position change. Data were analyzed using standard statistical tests. Results: Statistically significant difference in ETCP was observed during anteflexion of neck, hyperextension of neck, left lateral flexion of neck, right lateral flexion of neck, left lateral rotation of neck, right lateral rotation of neck, 10o recumbent position, supine position, Trendelenburg position, and right lateral 30° and 45° positions. Maximum increase in ETCP was seen during anteflexion of neck (31 ± 4.5; 22-42 cm H2O). Conclusion: Our study demonstrates significant deviations in ETCP from the recommended range following changes in the body position of mechanically ventilated patients, highlighting the need for the measurement of ETCP after each position change and maintenance of the same within the target range. How to cite this article: Roy O, Dasgupta S, Chandra A, Biswas P, Choudhury A, Ghosh S, et al. Relationship of Endotracheal Tube Cuff Pressures with Changes in Body Positions of Critically Ill Patients on Mechanical Ventilation: An Observational Study. Indian J Crit Care Med 2024;28(1):36-40.

Endotracheal Cuff-pressure Monitoring in ICU: A Standard of Care Yet to be Standardized, and Often Neglected.

How to cite this article: Kumar AKA. Endotracheal Cuff-pressure Monitoring in ICU: A Standard of Care Yet to be Standardized, and Often Neglected. Indian J Crit Care Med 2024;28(1):8-10.

The Effect of Topical Benzydamine Hydrochloride and Cuff Pressure Monitorization on Postoperative Sore Throat Due to Intubation.

OBJECTIVE: Postoperative sore throat (POST) is the most common discomfort after endotracheal intubation. Damage to the tracheal mucosa caused by inappropriate endotracheal tube (ETT) cuff pressure has been shown as the major factor. Monitoring the ETT cuff pressure at a certain value reduces this damage. Benzydamine hydrochloride (BH) has proven to be effective on sore throat and studies have shown that it is also effective on POST. In this study, the efficacy of BH and ETT cuff pressure monitoring on POST was evaluated. MATERIALS AND METHODS: After ethics committee approval 210 patients in the ASA (American Society of Anesthesiologists) I-III risk group undergoing elective surgery were included in the study. Routine anesthesia monitoring, induction, and maintenance were provided. Patients were randomly divided into three groups. Thirty minutes before surgery, the posterior pharyngeal wall was sprayed with BH in group 1 and distilled water in groups 2 and 3. Intraoperatively, the first and second groups were monitored to keep the ETT cuff pressure between 22 and 26 cmH2O, while no intervention was performed in the third group. The incidence and severity of postoperative dysphagia, hoarseness, and POST were questioned. RESULTS: There was no difference between demographic data, and gender was not associated with POST. There was a statistically significant difference between the first and second groups and the third group in terms of all three symptoms questioned (p<0.01). No difference was observed between the first and second groups. Side effect rates were similar. Smoking was not found to be associated with symptoms. CONCLUSION: The incidence and severity of POST, dysphagia, and hoarseness are reduced when the ETT cuff is inflated with a pressure of 22-26 cmH2O after intubation with a manometer and maintained at this pressure range throughout the operation. There was no beneficial effect of BH.

Measurements of Electrodermal Activity, Tissue Oxygen Saturation, and Visual Analog Scale for Different Cuff Pressures.

The quantification of comfort in binding parts, essential human-machine interfaces (HMI) for the functioning of rehabilitation robots, is necessary to reduce physical strain on the user despite great achievements in their structure and control. This study aims to investigate the physiological impacts of binding parts by measuring electrodermal activity (EDA) and tissue oxygen saturation (StO2). In Experiment 1, EDA was measured from 13 healthy subjects under three different pressure conditions (10, 20, and 30 kPa) for 1 min using a pneumatic cuff on the right thigh. In Experiment 2, EDA and StO2 were measured from 10 healthy subjects for 5 min. To analyze the correlation between EDA parameters and the decrease in StO2, a survey using the visual analog scale (VAS) was conducted to assess the level of discomfort at each pressure. The EDA signal was decomposed into phasic and tonic components, and the EDA parameters were extracted from these two components. RM ANOVA and a post hoc paired t-test were used to determine significant differences in parameters as the pressure increased. The results showed that EDA parameters and the decrease in StO2 significantly increased with the pressure increase. Among the extracted parameters, the decrease in StO2 and the mean SCL proved to be effective indicators. Such analysis outcomes would be highly beneficial for studies focusing on the comfort assessment of the binding parts of rehabilitation robots.

Continuous Versus Intermittent Control Cuff Pressure for Preventing Ventilator-Associated Pneumonia: An Updated Meta-Analysis.

OBJECTIVE: This study aimed to evaluate the effect of continuous control cuff pressure (CCCP) versus intermittent control cuff pressure (ICCP) for the prevention of ventilator-associated pneumonia (VAP) in critically ill patients. METHODS: Relevant literature was searched in several databases, including PubMed, Embase, Web of Science, ProQuest, the Cochrane Library, Wanfang Database and China National Knowledge Infrastructure between inception and September 2022. Randomized controlled trials were considered eligible if they compared CCCP with ICCP for the prevention of VAP in critically ill patients. This meta-analysis was performed using the RevMan 5.3 and Trial Sequential Analysis 0.9 software packages. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework was used to assess the level of evidence. RESULTS: We identified 14 randomized control trials with a total of 2080 patients. Meta-analysis revealed that CCCP was associated with a significantly lower incidence of VAP compared with ICCP (relative risk [RR] = 0.52; 95% confidence interval [CI]: 0.37-0.74; P < 0.001), although considerable heterogeneity was observed (I2 = 71%). Conducting trial sequential analysis confirmed the finding, and the GRADE level was moderate. Subgroup analysis demonstrated that CCCP combined with subglottic secretion drainage (SSD) had a more significant effect on reducing VAP (RR = 0.39; 95% CI = 0.29-0.52; P < 0.001). The effect of CCCP on ventilator-associated respiratory infection (VARI) incidence was uncertain (RR = 0.81; 95% CI = 0.53-1.24; P = 0.34; I2 = 61%). Additionally, CCCP significantly reduced the duration of mechanical ventilation (MV) (mean difference [MD] = -2.42 days; 95% CI = -4.71-0.12; P = 0.04; I2 = 87%). Descriptive analysis showed that CCCP improved the qualified rate of cuff pressure. However, no significant differences were found in the length of intensive care unit (ICU) stay (MD = 2.42 days; 95% CI = -1.84-6.68; P = 0.27) and ICU mortality (RR = 0.86; 95% CI = 0.74-1.00; P = 0.05). CONCLUSION: Our findings suggest that the combination of CCCP and SSD can reduce the incidence of VAP and the duration of MV and maintain the stability of cuff pressure. A combination of CCCP and SSD applications is suggested for preventing VAP.

Usefulness of an automatic cuff pressure controller (SmartCuff) in inhibiting gasleakage around the cuff after tracheal intubation: a randomized controlled study.

PURPOSE: 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%). CONCLUSION: Gas leakage may frequently occur after tracheal intubation, and the use of the SmartCuff can effectively maintain the sealing effect of the cuff.

Tonic cuff pressure pain sensitivity in chronic pain patients and its relation to self-reported physical activity.

OBJECTIVES: Physical inactivity is a global health concern and a significant problem among chronic pain patients. They often experience pain flare-ups when they try to increase their physical activity level. Most research on the relationship between pain sensitivity and physical activity has been on healthy participants. Data on chronic pain patients are lacking. Using cuff pressure algometry, this study investigated tonic cuff pressure pain sensitivity and its associations to self-reported physical activity and other patient-reported outcomes in chronic pain patients. METHODS: Chronic pain patients (n=78) were compared to healthy controls (n=98). Multivariate data analysis was used to investigate the associations between tonic cuff pressure pain sensitivity, physical activity, and other patient-reported outcome measures. RESULTS: The three most important variables for group discrimination were perceived health status (EQVAS: p(corr)=-0.85, i.e., lower in patients), depression (HADS-D: p(corr)=0.81, i.e., higher in patients), and the tonic cuff pressure pain sensitivity variable maximum pain intensity (VAS-peak-arm: p(corr)=0.75, i.e., higher in patients). In patients, the most important predictors for high VAS-peak-arm were female sex (p(corr)=-0.75), higher number of painful regions (p(corr)=0.72), higher pain intensity (p(corr)=0.55), followed by lower level of self-reported physical activity (p(corr)=-0.39). VAS-peak-arm in patients correlated negatively with self-reported physical activity (rho=-0.28, p=0.018). CONCLUSIONS: Physical activity may be the most important patient-changeable variable correlating to pain sensitivity. This study highlights the importance of more research to further understand how increased physical activity may decrease pain sensitivity in chronic pain patients.

A Prospective Randomized Controlled Trial of the Effect of Maintenance of Continuous Cuff Pressures (20 cmH2O vs 30 cmH2O) on Postoperative Airway Symptoms in Laparoscopic Surgeries.

INTRODUCTION: Recently, laparoscopic surgery has been used in many fields of surgery. It has been reported that cuff pressure becomes high during laparoscopic surgery. Increased cuff pressure may cause postoperative sore throat and hoarseness. Considering previous reports, we hypothesized that maintenance of a fixed low cuff pressure during laparoscopic surgery might be associated with low grades of postoperative sore throat and hoarseness. METHODS: The participants were 100 patients between 20 and 80 years of age who were scheduled to undergo laparoscopic surgery lasting over 2 hours. Patients were randomly allocated to two groups with endotracheal tube cuff pressures fixed at 20 cmH2O (low-pressure group; LPG) and 30 cmH2O (high-pressure group; HPG). We evaluated mainly sore throat and hoarseness on postoperative day 1 using a visual analog scale (VAS; 0-10 cm). Statistical comparisons of values were performed using the unpaired t-test, Mann-Whitney U-test, and chi-square test with values of p < 0.05 considered statistically significant. RESULTS: There were no significant differences in background characteristics between the two groups. Median postoperative scores for the LPG and HPG were 1 (interquartile range, 0-3) and 0 (0-2; p = 0.560) for sore throat and 2 (0-4) and 1 (0-3; p = 0.311) for hoarseness, respectively, and the differences were not significant. CONCLUSION: The effects of maintenance of a fixed low cuff pressure and a fixed high cuff pressure on the degrees of postoperative sore throat and hoarseness after laparoscopic surgery were the same and the grades were low.

Tourniquet Practice Among Orthopaedic Surgeons in Saudi Arabia.

Introduction This study aimed to evaluate the knowledge of tourniquet use among orthopedic surgeons in Saudi Arabia and assess the practical aspects of their use of tourniquets and the complications they have experienced in their practices. Materials and methods This cross-sectional study was conducted from December 2022 to February 2023. An online questionnaire was distributed among orthopedic surgeons and trainees in Saudi Arabia, and the surgeons' knowledge of tourniquet use was assessed using 17 questions. To investigate tourniquet usage, the participants were divided into three groups: orthopedic residents, specialists, and consultants. An upper limb cuff pressure (CP) of 200 mmHg and a lower limb CP of 250 mmHg were chosen as the cut-off values, and the doctors' choices were compared against literature recommendations using these measures. Result A total of 205 participants filled out the questionnaires; 130 residents, 15 consultants, and 60 specialists, with more males (175/205) than females responding. One hundred and twenty-one surgeons placed the cuff on patients by themselves, while 50 (24.3%) surgeons asked nurses for aid; 135 (65.6%) of them work in teaching hospitals, while 50 (24.3%) work in community hospitals. The incidence of post-tourniquet syndrome was unrelated to expertise (p=0.12). Conclusion When applied properly, tourniquets prevent excessive bleeding and keep the operative field clean during limb surgeries. This study aims to inspire the orthopedic community to reconsider long-held practices, especially regarding tourniquet pressure. The addition of ligature safety education to orthopedics training and outlining the settings and procedures for applying pressure should also be considered. The orthopedic community should set CP and process criteria to avoid complications. This study showed the importance of modifying the training of orthopedic residents to raise awareness and prevent unpleasant events from occurring.

Effect of transesophageal echocardiography probe on tracheal perfusion pressure and ventilatory parameters in pediatric patients undergoing cardiac surgery using cardiopulmonary bypass: A prospective observational study.

Background: Overinflation of cuffed endotracheal tubes and transesophageal echocardiography (TEE) probe causes increased intracuff pressure (CP) compromising tracheal perfusion pressure (TPP). Primary objective of the study was to assess CP, TPP on TEE probe insertion and examination during pediatric cardiac surgeries. Secondary objectives were to evaluate the effect of the probe on peak airway pressures (Ppeak), mean airway pressures (Pmean) and to monitor CP, TPP on cardiopulmonary bypass (CPB). Materials and Methods: This prospective observational study included fifty patients, aged 1-5 years undergoing cardiac surgeries using CPB. Following induction, TEE probe was introduced. CP, TPP, Ppeak, Pmean were measured before insertion of TEE probe (T1), during probe insertion (T2) and examination at mid-esophageal (T3), transgastric level (T4), and on removing probe (T6). CP, TPP were monitored on CPB (T5). Statistical analysis was done using paired t-test. Results: CP, Ppeak and Pmean increased significantly, while TPP decreased significantly from T1 to T2, T3, T4 (P < 0.001). CP, TPP decreased significantly at T5 in comparison to T6 (P < 0.001). In 48% of the patients CP increased above 30 cm H2O at T2. Conclusion: TEE probe causes an increase in CP and decreases TPP. Constant monitoring and maintaining CP, TPP in optimum range is recommended.

Comparison of the effect of pressure control and volume control ventilation on endotracheal tube cuff pressure in patients undergoing general anesthesia and mechanical ventilation: a parallel randomized clinical trial.

BACKGROUND: Endotracheal intubation and mechanical ventilation are prevalent interventions in the operating room and intensive care unit. Recently, the complications of endotracheal tube cuff pressure have been a topic of interest. Therefore, this study compared the effect of pressure control and volume control ventilation modes on the endotracheal cuff pressure rate in patients undergoing general anesthesia and mechanical ventilation. METHODS: In this triple-blinded randomized clinical trial, 50 patients undergoing open limb surgery and inguinal hernia were allocated to two groups of 25 based on inclusion criteria. After intubation, one group underwent ventilation on the pressure control ventilation mode, and the other underwent ventilation on the volume control ventilation mode. In both groups, using a manometer, the cuff's pressure was first adjusted in the range of 25-30 cm of water. Then, the cuff pressure was measured at 10, 20, and 30 min intervals. The data were statistically analyzed using independent t-test, and two-way repeated measures ANOVA. RESULTS: The present study's findings showed that cuff pressure has significantly decreased over time in both study groups (F = 117.7, P < 0.001). However, a repeated measures ANOVA with a Greenhouse-Geisser correction showed no interaction between time and groups (F = 0.019, P = 0.98). The two groups had no significant difference in cuff pressure (F = 0.56, P = 0.458). CONCLUSION: Since the cuff pressure has been significantly reduced in both groups over time, continuous monitoring of endotracheal tube cuff pressure in patients undergoing mechanical ventilation is essential. Therefore, it is suggested to keep the cuff pressure within the recommended range to prevent complications resulting from cuff pressure reduction, such as aspiration and ventilation decrease. TRIAL REGISTRATION: The study was registered in the Iranian Registry of Clinical Trial on 23/02/2019 (trial registration number: IRCT20181018041376N1).