Continuous Cuff Pressure Monitoring Research Articles

Management of adult mechanically ventilated patients: A UK-wide survey.

Mechanical ventilation is a common and often lifesaving intervention that is utilised in intensive care. However, the practices can vary between centres. Through this national survey we aim to gain more information about different strategies adopted across the UK. All adult intensive care units in the UK were approached to participate. The questionnaire was developed with an electronic survey engine and conducted between 09/11/2023 and 01/04/2024 (Survey Monkey®). The survey included questions on ventilator modes, settings, protocols/pathways, rescue strategies, immediate post-extubation period and follow-up. There were 196 responses from 104 hospitals. The most widely adopted start-up ventilation mode was pressure-regulated volume-controlled mode. For acute hypoxaemic respiratory failure (AHRF), most of respondents reported full (39.8%) or partial compliance (58.1%) with the ARDSnet protocol, with PEEP settings being the commonest deviation. Prone positioning (99.0%), followed by recruitment manoeuvres (91.3%) were commonly used rescue measures during AHRF. APRV (55.7%), inhaled (51.3%) and systemic pulmonary vasodilators (44.1%) were also commonly used. Conservative oxygen targets (SaO2 of 88%-92%) were commonly adopted (70.6%). As a care bundle, intermittent ETT cuff pressure monitoring was more common (65.5%) than continuous cuff pressure monitoring (20.0%). Propofol and alfentanil were the most common initial sedative and analgesia (99.5% and 56.9%) respectively. Routine volatile anaesthetic use was rare. Our survey has shown significant variation of practice in common but crucial elements of management of patients receiving mechanical ventilation. We hope the results in our survey highlight potential future areas of research. South-coast Peri-operative Audit and Research Collaborative (SPARC)Severn Trainee Anaesthetic and Critical Care Research group (STAR)Collaborative research in Anaesthesia in the Northeast (CRANE).

Comparison of incidence of sore throat with laryngeal mask airway Protector and laryngeal mask airway ProSeal: A randomised clinical trial.

Postoperative sore throat (POST) can be as high as 42% in supraglottic devices. LMA® Protector™ is a novel second-generation laryngeal mask airway (LMA) with Cuff Pilot™ technology that allows continuous cuff pressure monitoring. Elevated cuff pressure is a risk factor for POST in supraglottic devices, so we conducted this study to determine whether continuous cuff pressure monitoring can alleviate POST. This randomised double-blinded clinical trial compared the incidence of sore throat between LMA® Protector™ and LMA® ProSeal™ and was conducted in 118 patients scheduled for elective short surgical procedures. They were randomised to either LMA® Protector™ (Group PT) or LMA® ProSeal™ (Group P). The airway was secured with either of the two devices. The primary outcome was the incidence of sore throat at 1, 6, and 24 hours postoperatively and compared using the Chi-square test along with other parameters like first attempt success rate and blood staining of the device. The time taken for insertion and oropharyngeal seal pressure were compared using an independent t-test. The incidence of POST was low with Group PT (12%) compared to Group P (28.8%) (P = 0.005). The mean oropharyngeal seal pressure was significantly higher in Group PT than in Group P [33.72 (3.07) versus 27.72 (3.88) cm of H2O], P < 0.005. The first attempt success rate was 81.2% and 100% in LMA® Protector™ versus LMA® ProSeal™. LMA® Protector™ had a reduced incidence of POST compared to LMA ProSeal. However, a longer insertion time and difficult placement may be a concern.

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.

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. 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 24h post-extubation. Secondary outcomes included cough, hoarseness, postoperative nausea and vomiting (PONV) incidence, and post-extubation pain severity. The incidence of sore throat at rest within 24h 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 24h 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 24h post-extubation. 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 24h after tracheal tube removal in gynecological laparoscopic surgery patients. The study was registered at www.chictr.org.cn (ChiCTR2200064792) on 18/10/2022.

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

BackgroundEndotracheal 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.MethodsIn 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.ResultsThe 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).ConclusionSince 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 registrationThe study was registered in the Iranian Registry of Clinical Trial on 23/02/2019 (trial registration number: IRCT20181018041376N1).

Pressure changes in the endotracheal tube cuff in otorhinolaryngologic surgery: a prospective observational study.

Inflation of the endotracheal tube cuff is needed for providing ventilation. Cuff pressure should be maintained inside the appropriate range to prevent critical airway complications. The purpose of this study is to evaluate the pressure changes in the endotracheal tube cuff during otorhinolaryngologic surgery. This single-center observational study was conducted at Severance Hospital in Korea between April 2020 and November 2020. Patients aged >20 years scheduled to undergo otorhinolaryngological surgical procedures were enrolled. Patients undergoing planned tracheostomy and those who were slated for uncuffed endotracheal tube use were excluded. Intubation was performed after the induction of general anesthesia. A pressure transducer was connected to the pilot balloon of the endotracheal tube, and cuff pressure was continuously monitored until extubation. If the cuff pressure was not appropriate for more than 5 min, it was adjusted to the appropriate range by injecting or removing air. The percentage of time for which the cuff pressure remained within the appropriate range was calculated and defined as the time in the therapeutic range (TTR). The presumed cause for the rise or fall in cuff pressure was identified. In total 199 patients, alterations in cuff pressure outside the appropriate range occurred in 191 patients (96.0%). The mean TTR was 79.7% (SD 25.0%), and head and neck surgery had the lowest mean TTR of 69.0% compared to ear and nose surgeries (94.2 and 82.1%, respectively). Sixty-eight patients (34.2%) demonstrated inadequate endotracheal tube cuff pressure for more than 20% of the total anesthesia time. Twenty-six patients (13.1%) demonstrated optimal endotracheal tube cuff pressure for less than 50% of the total anesthesia time. The causative factors inducing inappropriate cuff pressure were found to vary, including positional changes, surgical procedure, anatomical manipulation, and anesthetic procedure. In otorhinolaryngologic surgery, cuff pressure increased or decreased outside the appropriate range due to various factors. Therefore, we suggest close continuous monitoring of cuff pressure during anesthesia for otorhinolaryngologic surgery. clinicaltrials.gov, identifier NCT03938493.

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

BackgroundPostoperative sore throat (POST) is a common postoperative complication after endotracheal tube removal. There are still no effective preventive methods for POST. The aim of this trial is to confirm whether maintaining intraoperative cuff pressure below the tracheal capillary perfusion pressure could effectively reduce the incidence of POST among patients undergoing gynecological laparoscopic surgery.MethodsThis study is a single-center, randomized, parallel-controlled, superiority trial with a 1:1 allocation ratio. Sixty patients whose age is between 18 and 65 years and scheduled for gynecological laparoscopic surgery will be randomized to the cuff pressure measurement and adjustment (CPMA) group and the only cuff pressure measurement without adjustment group (control group). The primary endpoint is the incidence of sore throat at rest within 24 h after extubation. The secondary endpoints include the incidence of cough, the incidence of hoarseness, the incidence of postoperative nausea and vomiting (PONV), POST, and pain intensity within 24 h after extubation. Blocked randomization will be conducted with a computer-generated central randomization online service. The blind method will be applied to subjects, data collectors, outcome evaluators, and statisticians. Outcome assessments will be performed at 0 h and 24 h post-extubation.DiscussionThis randomized controlled study hypothesizes that cuff pressure is the primary influencing factor of POST. By continuous monitoring of endotracheal tube cuff pressure and maintaining it within the range of 18–22 mmHg compared with only continuous measurement without adjustment, it aims to prove that continuous measurement and adjustment of endotracheal tube cuff pressure could be effective in reducing the incidence of POST in gynecological laparoscopic surgery patients. The result of this study could be used as a reference for future multicenter studies to confirm the effect of cuff pressure on POST and provides a scientific theoretical basis for preventing POST to further support comfort medicine.Trial registrationChinese Clinical Trial Registry ChiCTR2200064792. Registered on 18 October 2022. This protocol (version 1.0, 16 March 2022) was approved by the Ethics Committee of Beijing Chaoyang Hospital.

Intermittent versus continuous control of tracheal cuff pressure in patients undergoing mechanical ventilation: Asystematic review and meta-analysis.

To evaluate the effects and safety of intermittent versus continuous control of cuff pressure in patients with mechanical ventilation. Tracheal cuff pressure management is vital to the prognosis of patients with mechanical ventilation. A meta-analysis. This meta-analysis was conducted and reported according to the PRISMA checklist. We searched Pubmed, Embase, The Cochrane Library, BMJ Best Practice, Web of Science, ProQuest Dissertations, as well as the Chinese Biomedical Literature Database, Wanfang, and China national knowledge infrastructure databases up to 5 August 2022 for randomised controlled trials (RCTs) on the intermittent versus continuous control of cuff pressure. Review Manager 5.3 software was used for relevant data analysis. A total of 18 RCTs involving 1998 patients with mechanical ventilation were included. The synthesised outcomes indicated that continuous control of cuff pressure is beneficial to reduce the incidence of ventilator-associated pneumonia (VAP) [RR=0.41, 95%CI (0.35, 0.49)], aspiration [RR=0.36, 95%CI (0.21, 0.63)], duration of mechanical ventilation [MD=-3.23, 95%CI (-4.66, -1.79)], length of ICU stay [MD=-4.12, 95%CI (-5.40, -2.83)], and increase the volume of subglottic drainage [MD=18.54, 95%CI (16.50, 20.58)]. There was no significant difference in the mortality between two groups [RR=1.01, 95%CI (0.84, 1.21)]. Egger regression analyses showed that there were no obvious publication biases in the synthesised results (all p > .05). Existing evidence shows that compared with intermittent monitoring of cuff pressure, continuous monitoring of cuff pressure can reduce the occurrence of aspiration and VAP, shorten the patient's duration of mechanical ventilation and length of ICU stay. Continuous monitoring of cuff pressure is more beneficial and should be promoted in clinical nursing care of patients undergoing mechanical ventilation.

Comparison of Normal Saline and Alkalinized 2% Lignocaine to Reduce Emergence Phenomenon and Post-Intubation Morbidities: A Prospective, Double-Blind, Randomized Study.

Endotracheal intubation for airway management in general anesthesia is associated with post-intubation morbidities due to tracheal mucosa injury caused by endotracheal tube (ETT) cuff. Nitrous oxide (N2O) diffuses into tracheal tube cuffs filled with air. The rate of diffusion of N2O through the membrane is proportional to its concentration gradient. High-volume low-pressure cuffs expand with only a slight increase in pressure until fully inflated. At this point, owing to the inelasticity of the material, the cuff pressure rises rapidly. This increased pressure can damage the tracheal mucosa. This phenomenon can be avoided, if we inflate the cuff with either a liquid or a gas mixture identical to the inspired gas and monitor the cuff pressure and volume at regular intervals. When lignocaine is used to inflate the ETT cuff, it diffuses to the underlying tracheal mucosa. Thus reducing local irritation and inflammation of the airway through its local anesthetic action. Alkalinization of lignocaine increases its rate of diffusion across the ETT cuff. It also reduces the dose of local anesthetic required to achieve the desired result. We sought to determine the benefits of filling the ETT cuff with alkalinized lignocaine 2% over normal saline, to prevent ETT-induced emergence phenomenon and reduce the incidence of post-intubation morbidities like sore throat, hoarseness, and nausea. This prospective, randomized, double-blind, and comparative study was done at a multispecialty hospital. A total of 120 individuals ofAmerican Society of Anesthesiologists (ASA) physical status 1 and 2, posted for surgery under general anesthesia, were randomly selected and divided into two groups: alkalinized 2% lignocaine group (group L) and normal saline group (group S). After induction of general anesthesia, the airway was secured with appropriate-sized ETT. The ETT cuff was inflated with either of the study media. Continuous cuff pressure monitoring was done to keep cuff pressure below 30 centimeters of water (cm of H2O), at all times. At extubation, the response was evaluated in terms of percentage change in heart rate (HR) and blood pressure from baseline, coughing, bucking, and restlessness. All the surgeries lasted more than two hours. Post-operatively, the patients were evaluated for sore throat and hoarseness, at regular intervals of up to 24 hours. ETT cuff pressure was initially less in group S, which rose to a significantly higher level at extubation, compared to group L (p <0.001). At extubation, there was a significant increase in HR and systolic blood pressure (SBP) from baseline, in group S than in group L (p <0.001 and p=0.001, respectively).The incidence of cough and restlessness was less in group L, compared to group S (p<0.001 and p=0.002, respectively). Mean extubation time and emergence time was more in group S than in group L (p<0.001). Post-operatively, the incidence and severity of sore throat were significantly higher in group S than in group L (p<0.001). Meanwhile, the incidence of hoarseness and nausea was comparable in the two groups. Continuous ETT cuff pressure monitoring helps to keep cuff pressure below tracheal mucosa capillary occlusion pressure. Filling the ETT cuff with alkalinized lignocaine further reduces extubation response and post-intubation morbidities.

Inner Lumen Tracheostomy Tube Capable of Continuous Monitoring of Cuff Pressure.

Tracheostomy is one of the most important airway management procedures in patients with respiratory problems. This procedure might be the only option for patients with airway and respiratory problems, who are not able to have an appropriate ventilation and oxygenation. For this purpose, tracheostomy tubes are used with different applications. One of these types of tubes is the cuffed tracheostomy tube, used for fixation, positive pressure ventilation and aspiration prevention. Nevertheless, there are two common problems with using these regular tracheostomy tubes. First, these tracheostomy tubes do not have a unique cuff pressure monitoring system. Although there are portable monitoring devices for such purpose in intensive care units (ICU), they are shared among several patients, increasing the risk of infection transmission. Second, due to the presence of the patient’s thick secretions, the tracheostomy tube becomes obstructed and inefficient. The pathway does not get open even through suction and thus the tracheostomy tube must be replaced. In order to resolve these problems, the inner lumen tracheostomy tube capable of continuous monitoring of cuff pressure has been invented with two techniques, which set it apart from other related tools. The invented optimized tracheostomy tube has been developed with different techniques through creating a disposable monometer system attached to it as well as a removable inner lumen embedded in it.

Study on mechanical ventilation pressure under continuous cuff pressure monitoring in critical patients

To explore the effective pressure range under continuous cuff pressure monitoring in critical patients with mechanical ventilation, so as to achieve the goal of ensuring ventilation quality and reducing mucosal injury without increasing the incidence of endotracheal catheter displacement and aspiration. Ninety critically ill patients with non-pulmonary diseases admitted to the department of intensive care unit (ICU) of Airport Hospital of Tianjin Medical University from June 2017 to June 2019 were enrolled, and divided into three groups according to the random number table, with 30 patients in each group. For all patients in the three groups , the head of the bed was raised by 30 degree angleand the balloon was measured continuously. Cuff pressure in the three groups were maintained at 20, 25 and 30 cmH2O (1 cmH2O = 0.098 kPa) respectively. The patient's air leakage, oxygen saturation, tracheal tube displacement of each group were recorded every hour when the patients were calm. Fiberbronchoscope was used to aspirate sputum during extubation to check for mucosal damage. Chest X-ray examination was used to evaluate pulmonary infection and sputum bacteria culture examination was conducted at the same time. There was no significant difference in gender, age and critical condition among the three groups. The number of patients with airway mucosal injury in the 30 cmH2O group was significantly higher than that in the 20 cmH2O group (cases: 8 vs. 4, P < 0.05). There was no significant difference in airway mucosal injury between Group 20 cmH2O and Group 25, Group 25 cmH2O and Group 30 cmH2O. When the balloon pressure was 20, 25, and 30 cmH2O, there was no significant difference in air bag leakage (cases: 14, 10, 12), trachea catheter displacement (cases: 18, 11, 16), ventilator-associated pneumonia (cases: 3, 4, 3), all P > 0.05, and there was no significant difference in mechanical ventilation time and the hospitalization time [mechanical ventilation time (hours): 77.07±65.34, 80.80±70.20, 77.60±65.23; the length of ICU stay (days): 5.70±3.74, 5.30±4.57, 6.23±3.51, all P > 0.05]. The cuff pressure of 20 cmH2O will not increase the mechanical ventilation time and hospitalization time of patients, while 20 cmH2O is much safer in airway mucosal injury.

The Changes of Endotracheal Tube Cuff Pressure during Manual and Intermittent Controlling in Intensive Care Units.

Background:Usually, the endotracheal tube cuff pressure is controlled by cuff pressure monitoring. However, the intermittent pilot-manometer connection and disconnection may cause a change in the adjusted pressure. This study aimed to investigate changes in the endotracheal tube cuff pressure using both manual and intermittent controls.Materials and Methods:A semi-experimental within-subject design was conducted. Fifty-nine intubated patients in the Mazandaran Intensive Care Units (ICUs) participated through convenience sampling in 2018. In the control condition, first, the cuff pressure was adjusted in 25 cm H2O then it was measured without manometer-pilot disconnection at 1 and 5 min intervals. In the intervention condition, cuff pressure was immediately adjusted in 25 cm H2O then it was measured with manometer-pilot disconnection in the 1st and 5th minutes. Data analysis was performed using Independent t-test, Chi-square test, and Phi coefficient.Results:The mean and Standard Deviation (SD) change of cuff pressure after 1 minute, from 25 cm H2O, in the intervention condition was 20.22 (3.53) cm H2O. The mean (SD) of this change in the control condition was 25.22 (3.39) cm H2O. This difference was significant (t116 = 7.83, p < 0.001, d = 1.44). The mean (SD) change of cuff pressure after 5 minutes, from 25 cm H2O, in the intervention condition was 19.11 (2.98) cm H2O. The mean (SD) of this change in the control condition was 25.47 (4.53) cm H2O. This difference was significant (t116 = 9.24, p < 0.001, d = 1.70).Conclusions:The tracheal tube cuff pressure has been significantly reduced during manual intermittent measuring. Therefore, it is suggested that continuous cuff pressure monitoring and regulation should be used.

A Literature Review on Strategies Preventing Ventilator-Associated Pneumonia: Role of Endotracheal Cuff Pressure, Cuff Material, and Cuff Shape

ObjectivesTo provide an overview of existing literature regarding the effects of ETT cuff pressure, cuff material, and cuff shape on VAP prevention in adult ventilated patients.BackgroundVentilated patients are at risk of ventilator-associated pneumonia (VAP), which can result in many adverse consequences, such as increased length of stay, mortality, and hospital cost. Endotracheal tube (ETT) insertion is a commonly used measure for mechanical ventilation. However, ETT cuff pressure, special cuff material, and special cuff shape may affect the occurrence of VAP in ventilated patients, but the evidence for their effects on VAP prevention has not been synthesized.MethodsA literature review was conducted.FindingsTwenty-two studies involving 8,809 patients were included in this literature review. The reviewed studies showed inconsistent findings of the effects of continuous ETT cuff pressure monitoring (compared with intermittent pressure monitoring), polyurethane ultrathin tracheal tube (compared with polyvinyl chloride tracheal tube), and taper-shaped cuff (compared with conical-shaped cuff) on the prevention of VAP. Two studies reported consistent findings that silver-coated ETT significantly reduced bacterial load and incidence of VAP compared with uncoated ETT, but the evidence level was relatively weak.ConclusionThis literature review provides an initial and brief overview of the effects of ETT cuff pressure, cuff material, and cuff shape on preventing VAP. However, the effectiveness of these interventions remains inconclusive due to the inadequate evidence and low quality of previous studies. The intervention effects should be synthesized using a quantitative method and laboratory studies with rigorous design are needed to provide more solid evidence.

Prevention of Ventilator-Associated and Early Postoperative Pneumonia Through Tapered Endotracheal Tube Cuffs: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Microaspiration of subglottic secretions is considered a major pathogenic mechanism of hospital-acquired pneumonia, either early postoperative or ventilator-associated pneumonia. Tapered endotracheal tube cuffs have been proposed to provide a better seal of the extraluminal airway, thereby preventing microaspiration and possibly hospital-acquired pneumonia. We performed a systematic review and meta-analysis to assess the value of endotracheal tubes with tapered cuffs in the prevention of hospital-acquired pneumonia. A systematic search of MEDLINE, EMBASE, CENTRAL/CCTR, ClinicalTrials.gov, and ICTRP was conducted up to March 2017. Eligible trials were randomized controlled clinical trials comparing the impact of tapered cuffs versus standard cuffs on hospital-acquired pneumonia. Random-effects meta-analysis calculated odds ratio and 95% CI for hospital-acquired pneumonia occurrence rate between groups. Secondary outcome measures included mortality, duration of mechanical ventilation, length of hospital and ICU stay, and cuff underinflation. Six randomized controlled clinical trials with 1,324 patients from intensive care and postoperative wards were included. Only two studies concomitantly applied subglottic secretion drainage, and no trial performed continuous cuff pressure monitoring. No significant difference in hospital-acquired pneumonia incidence per patient was found when tapered cuffs were compared with standard cuffs (odds ratio, 0.97; 95% CI, [0.73-1.28]; p = 0.81). There were likewise no differences in secondary outcomes. Application of tapered endotracheal tube cuffs did not reduce hospital-acquired pneumonia incidence among ICU and postoperative patients. Further research should examine the impact of concomitant use of tapered cuffs with continuous cuff pressure monitoring and subglottic secretion drainage.

A design and study of a novel electronic device for cuff-pressure monitoring

To design a novel electronic device for measuring the pressure in the cuff of the artificial airway; and to study the advantage of this device on continuous and intermittent cuff pressure monitoring. (1) a portable electronic device for cuff pressure measurement was invented, which could turn pressure signal into electrical signal through a pressure transducer. Meantime, it was possible to avoid pressure leak from the joint and the inside of the apparatus by modified Luer taper and sophisticated design. If the cuff pressure was out of the normal range, the apparatus could release a sound and light alarm. (2) Six traditional mechanical manometers were used to determine the cuff pressure in 6 tracheal tubes. The cuff pressure was maintain at 30 cmH2O (1 cmH2O = 0.098 kPa) by the manometer first, and repeated every 30 seconds for 4 times. (3) Study of continuous cuff pressure monitoring: We used a random number generator to randomize 6 tracheal tubes, 6 mechanical manometers and 6 our products by number 1-6, which has the same number of a group. Every group was further randomized into two balanced groups, one group used the mechanical manometer first, and the other used our product first. The baseline pressure was 30 cmH2O, measurement was performed every 4 hours for 6 times. When traditional mechanical manometer was used for cuff pressure monitoring, cuff pressure was decreased by an average of 2.9 cmH2O for each measurement (F = 728.2, P = 0.000). In study of continually monitoring, at each monitoring point, the pressure measured by electronic manometer was higher than the mechanical manometer. All the pressures measured by mechanical manometer were dropped below 20 cmH2O at 8th hour, and there was no pressure decrease below 20 cmH2O measured by electronic manometer in 24 hours by contrast. In study of intermittent monitoring, the same result was found. The pressure was dropped significantly with time when measured by mechanical manometer (F = 61.795, P = 0.000), the drops below 20 cmH2O began at 8th hour; but when measured by electronic manometer, all the value stayed unchanged around the baseline in 24 hours (F = 0.511, P = 0.796). Compared with traditional mechanical manometer, cuff pressures monitored by our novel electronic manometer were steadier in both continuous and intermittent monitoring. The device is compact and convenient, and can provide a good solution for continuously monitor of the tracheal cuff pressure.

Effects of continuous artificial airway cuff pressure monitoring in preventing ventilator-associated pneumonia

Objective To investigate the effects of different control methods in cuff pressure (Pcuff) on the incidence of ventilator associated pneumonia (VAP) for the patient receiving mechanical ventilation with implication of artificial airway by oral endotracheal intubation. Methods A total of 80 patients receiving mechanical ventilation with oral endotracheal were numbered according to the order of using mechanical ventilation. Patients with odd numbers were recruited into intervention group (40 cases) , while patients with even numbers were included in control group (40 cases) . Patients in intervention group used Arto continuous air pressure control device to continuously control the cuff pressure, while the control group used German VBM airbags pressure gauge to measure and regulate cuff pressure three times a day. Sputum specimens of patients were taken and pepsin levels were tested at tracheal intubation, 48 h and 96 h post mechanical ventilation. Pcuff, pepsin levels in sputum specimens and the incidence of VAP were compared between two groups. Results At 96 h post mechanical ventilation, Pcuff of patients in intervention group were in the ideal range (20~30cmH2O) for 479 times, and in control group the number were 389 times. The difference was statistically significant (χ2=124.830, P<0.01) . The pepsin levels of sputum specimens in intervention group were (617.32±67.13) and (653.13±71.32) ng/ml at 48 h and 96 h post mechanical ventilation, both of which were significantly lower than those in control group (t=-11.217, -14.500; P<0.01) . The incidences of VAP were 25.0% and 47.5% in intervention and control group respectively, with statistically significant difference between two groups (χ2=4.381, P<0.05) . Conclusions The continuous air pressure control device can better keep the air pressure in the ideal range and reduce gastric contents aspiration of the patients with mechanical ventilation so as to reduce the incidence of VAP. Key words: Ventilator-associated pneumonia; Pepsin; Misaspiration; Continuous artificial airway; Cuff pressure

Comparison of the performance of the self-pressurized air-Q intubating laryngeal airway with the LMA–ProSeal in pediatric patients under general anesthesia: a randomized controlled trial

Background Self-pressurized air-Q intubating laryngeal airway (air-Q SP) is a supraglottic airway device with a noninflatable cuff that does not need continuous monitoring of the cuff pressure. As the ProSeal laryngeal mask airway (PLMA) is considered the ‘state-of-the-art’ supraglottic device, we conducted this randomized trial to evaluate the safety and efficacy of air-Q SP compared with that of PLMA in pediatric patients. Patients and methods The study included 70 pediatric patients aged from 4 to 15 years undergoing elective surgery under general anesthesia who were randomized to either the air-Q SP group or the PLMA group. The primary outcome parameter in this study was the oropharyngeal leak pressure, and the secondary outcome parameters were ease of insertion, time of insertion, first attempt insertion success rate, number of gastric insufflations, fiberoptic glottic view, and complications related to the supraglottic airway device use. Results There was no significant difference between air-Q SP and PLMA regarding first insertion success rate, ease of insertion, oropharyngeal leak pressure, number of gastric insufflations, number of manipulations required to adjust the airway, and complications. Time to insert the air-Q SP was significantly shorter than that of PLMA (13.2±4.2 vs. 17.5±4.8 s, P=0.03). The fiberoptic view was significantly better with air-Q SP than with PLMA (P=0.018). Conclusion The performance of air-Q SP is comparable to that of PLMA as a primary airway device during general anesthesia in pediatric patients, with a shorter insertion time and better fiberoptic view for air-Q SP.

Bougie Effects on Endotracheal Cuff Pressure and Sore Throat in Bariatric Surgery

Purpose: The purpose of this study was to evaluate the effects of a bougie insertion on the endotracheal cuff pressure and incidence of sore throat in sleeve gastrectomies. Materials and Methods: In this study, 40 patients scheduled for sleeve gastrectomies were enrolled and randomly allocated into two groups. The endotracheal tube (ETT) cuff pressures were set to 25 mmHg after intubation and the pressures were continuously monitored. In Group 1, the ETT cuff pressure was adjusted to 25 mmHg after the insertion of the bougie device, whereas in Group 2, the cuff pressure was not manipulated after the insertion of the bougie. The peak airway pressures and cuff pressures were recorded every 5 min in both groups, and the bougie insertion time, bougie duration, laryngoscopic and bougie complications, and surgery durations were noted. The incidence of postoperative sore throat was assessed and classified as none, mild, moderate, and severe. Results: There were no differences between the groups in the demographic variables, duration of surgery, peak airway pressure, or duration of bougie use. The bougie insertion time was at 28 ± 9 and 30 ± 10 min into the surgery in Groups 1 and 2, respectively. The cuff pressures were significantly higher in Group 2 at 20, 25, 30, and 35 min (p < 0.05), and the endotracheal cuff pressures exceeded 30 mmH2O in nine patients in Group 2. The postoperative sore throat scores were significantly higher in Group 2 at the 30th minute and at the 2nd and 24th hours. Conclusion: The insertion of a bougie may increase the cuff pressure and exacerbate a postoperative sore throat. Continuous cuff pressure monitoring and readjusting the cuff pressure after the bougie insertion procedure may alleviate a postoperative sore throat in bariatric surgery.

Reduced Endotracheal Tube Cuff Pressure to Assess Dysphagia After Anterior Cervical Spine Surgery.

This was a prospective, randomized control pilot study. The aim of this study was to determine whether continuous monitoring and adjustment of the endotracheal tube cuff pressure (ETTCP) to 15 mm Hg during ACSS would alter the incidence of postoperative dysphagia. Postoperative dysphagia is a recognized potential complication of anterior cervical spine surgery (ACSS). Recent findings on preventive measures suggest that certain intraoperative practices may minimize this complication. Fifty patients undergoing ACSS, arthroplasty, or fusion, completed routine lateral cervical preoperative plain films and questionnaires [Dysphagia Disability Index (DDI), Bazaz-Yoo Dysphagia Score (BYDS), and Short Form (36) Health Survey]. Patients were randomized into 2 groups: treatment group with ETTCP maintained at 15 mm Hg and control group with cuff pressure monitored without manipulation. Radiographs and questionnaires were obtained at 24 hours, 6 weeks, and 3 and 6 months postsurgery to assess soft tissue thickness and rates of dysphagia. There were no significant differences between the groups in the soft tissue thickness or questionnaire scores at any timepoint (P>0.05). Within-group analysis revealed treatment and control groups had a significantly higher 24-hour postoperative soft tissue thickness and questionnaire scores compared with follow-up measurements (P<0.05). In the pooled group (n=50), the 24-hour postoperative DDI, BYDS, and soft tissue thickness were significantly higher compared with all other timepoints (P<0.01). DDI scores ≥10 related to dysphagia were in 59% of patients at 24 hours, 35% at 6 weeks, 24% at 3 months, and 18% at 6 months. This study suggests decreased ETTCP has no effect on the prevalence of dysphagia. The incidence of dysphagia decreases over time and normalizes by 6 months postsurgery.

Continuous monitoring of endotracheal tube cuff pressure: best practice in intensive care unit

The endotracheal tube cuff pressure must be maintained within an optimal range of 20-30 cmH2O, which ensures ventilation, prevents aspiration of secretions and guarantees a good tracheal perfusion. To describe changes in the endotracheal tube cuff pressure over time through a continuous monitoring device, and assess the number of nursing actions. Observation of 72 patients admitted to a general ICU and monitored for 12 hours, with a continuos monitoring device of endotracheal tube cuff pressure (PressureEasy(®)). During the first four hours 4 cases (5.6%) of underinflated cuff were observed, and 5 (6.9%) of overinflation. From the fifth to the eighth hour 7 (9.7%) patients showed a pressure <20 cmH2O, and 3 (4.2%) >30 cmH2O. During the last four hours 22 cases (30.5%) of underinflated cuff, and 4 (5.6%) of overinflation were observed. More than half of the patients (n=38, 52.8%) did not require any intervention of inflation or deflation of the cuff, 25 (34.7%) only one and 7 (9.7%) patients two, and twe patients, three. The majority of patients required the inflation of the cuff. Our study supports the need of continuous endotracheal tube cuff pressure monitoring to promptly identify deviations from the pressure ranges, allowing their rapid correction.

Significant reduction in ventilator-associated pneumonia with the Venner-PneuX System in high-risk patients undergoing cardiac surgery: the Low Ventilator-Associated-Pneumonia study.

This study assessed whether the Venner-PneuX endotracheal tube (ET) system, which has sub-glottic suction as well as irrigation ports and continuous cuff-pressure monitoring, is associated with a reduction in ventilator-associated pneumonia (VAP) when compared with the standard ET in high-risk patients undergoing cardiac surgery. This was a single-institution, prospective, randomized control trial. Patients were categorized as either Group A (Venner-PneuX ET tube, n = 120) or Group B (Standard ET tube, n = 120). Inclusion criteria included patients over the age of 70 years and/or impaired left ventricular function (LVEF <50%) undergoing cardiac surgery. Patients were monitored for VAP for up to 48 h post extubation and the diagnosis of VAP was according to the centres for disease control definition. There were no significant differences in the patients' demographics. The mean (SD) ages for the two groups were 72.4 (8.2) and 72.1 (7.4) years (P = 0.6), respectively. The mean EuroSCORE was 6.39 (2.2) for Group A and 6.48 (2.6) for Group B (P = 0.9). The median intubation times were 14.7 (7.3, 2927.2) h and 13 (2.5, 528.7) h, respectively. VAP incidence was significantly lower in the Venner-PneuX ET group, being 10.8% when compared with 21% in the standard ET group (P = 0.03). There was no significant difference between the two groups in terms of intensive care unit stay (P = 0.2) and in-hospital mortality (P = 0.2). A binary logistic regression analysis (type of ET tube, age, LVEF, history of lung disease, smoking history, surgical procedure, EuroSCORE, cardiopulmonary bypass time, blood transfusion, intubation duration among others) confirmed that the Venner-PneuX ET tube was associated with significant VAP reduction (Odds ratio 0.45, P = 0.03). The Venner-PneuX VAP prevention system is associated with a significant reduction in VAP. This can potentially lead to significant cost reductions and should be implemented as part of the VAP reduction bundle.