Cuff Shape Research Articles

The effect of the endotracheal tube cuff shape on post-operative sore throat in surgeries longer than 120 min in supine position

The effect of the endotracheal tube cuff shape on post-operative sore throat in surgeries longer than 120 min in supine position

The Effect of Endotracheal Tube Cuff Shape on Post-extubation Sore Throat in Critically Ill Patients in a Rural Tertiary Care Hospital.

Patients admitted to the critical care unit often require extended periods of mechanical ventilation. After extubation, patients often report discomfort in their throats, coughing, and hoarseness of voice. These symptoms have been linked to the shape of the cuff on the endotracheal tube and are described in terms of the surface area of the cuff in contact with the trachea. During this pilot study, 160 adults receiving intensive primary care were randomly assigned to one of two groups (Gathering A or Gathering B; 80 patients each). Intubated patients were separated into two groups: Group C consisted of those who wore a looser, barrel-shaped sleeve, and Group T consisted of those who wore a more restrictive sleeve. The severity of post-extubation side effects was assessed, including sore throat, dry voice, and hack, and the occurrence of these symptoms was also documented. Neither the number of intubation attempts nor the experience level of the residents who performed them differed significantly between the two groups (p > 0.05). A smaller percentage of patients in Gathering T experienced sore throats in the first, 12th, and 24th hours after extubation compared to patients in Group C at these same time points (p = 0.05). With time passing, fewer people in Group C and Group T experienced hoarseness of voice after extubation. There is a declining trend in the incidence of cough post-extubation in Group T, as compared to an initial increase in the trend for cough post-extubation with a gradual decline as time progressed in Group C. There is an overall decrease in the incidence of post-extubation emergence phenomena with tapered shape cuffed endotracheal tubes when compared with conventional cylindrical type cuffed endotracheal tubes.

Alkalized lidocaine in a tapered cuff suppresses endotracheal tube-induced hemodynamic changes: a randomized controlled trial.

The use of an endotracheal tube (ET) cuff filled with alkalized lidocaine (AL) can suppress ET-induced emergence phenomena, such as hypertension, tachycardia and coughing, and postoperative sore throat (POST) and hoarseness (PH). The efficacy of intracuff lidocaine may vary depending on the cuff shape, but there has been no study on the effects of a tapered cuff filled with AL. We examined whether intracuff AL suppresses ET-induced emergence phenomena, POST and PH. Sixty-two patients were enrolled in this study and the patients were randomly allocated to a group in which the tapered cuff was filled with AL (Group AL) and a group in which the tapered cuff was filled with normal saline (Group S). The primary outcomes of this study were changes in mean blood pressure (MBP) and heart rate (HR) at extubation. MBP, HR and the number of coughs were recorded before and up to 10min after extubation. The degree of POST and the incidences of POST and PH were recorded at 15min, 2h and 24h after extubation. Changes in MBP before extubation and HR before and after extubation were significantly lower in Group AL than in Group S (p < 0.025). The number of coughs at extubation and the incidence of PH at 2h after extubation were significantly lower in Group AL than in Group S (p < 0.0001 and p = 0.014, respectively). AL in a tapered cuff significantly suppresses ET-induced cardiovascular changes in MBP and HR.

S-58-3: HOW COULD CONTINUOUS CUFFLESS AUTOMATED BLOOD PRESSURE MEASUREMENT DEVICES CONTRIBUTE TO HYPERTENSION MANAGEMENT?

Evidence that hypertension is the most importat global risk factor for cardiovascular morbidity and mortality, and demonstration of the cardiovascular protection offered by antihypertensive treatment, have been based on upper-arm cuff blood pressure (BP) measurements. This approach is recommended by current hypertension guidelines for BP measurement in clinical practice, as well as for validation of novel BP measuring devices. However, the spot or intermittent BP measurements in static conditions allowed by arm-cuff devices are unable to identify and track the continuous and rapid BP changes characterizing daily life. Moreover, cuff-based BP measurements are exposed to errors related to cuff size, shape and positioning, and cuff inflation may itself induce an alerting response and produce discomfort in the users during daily activities and in particular during sleep, which may modify the measured BP levels. To face these issues, use of continuous recordings techniques, not based on arm-cuff inflation, would be required. This is possible through intra-arterial recordings, which however are not feasible in daily practice because of their invasiveness. An alternative solution is represented by photoplethysmographic volume-clamp method for finger BP monitoring which, however, is difficult to implement in clinical practice because of its cost and complexity. Technological progress is now offering an increasingly large and heterogeneous series of cuffless BP monitors, which estimate BP based on sensors, signal processing and algorithms embedded in wearable devices, smartphones or pocket devices. These cuffless devices might allow for comfortable and continuous BP recordings, detecting rapid BP changes during day and night sleep, thus offering information on both short, mid and long term BP variability. Cuffless devices might also be useful for continuous non invasive BP monitoring in different clinical settings, including ICUs, during anaesthesia, in patients with arrhythmias, hypotension/syncope, and other transient conditions affecting BP levels and variability. Moreover, cuffless BP measurement devices connected to telemonitoring facilities or smartphones apps may improve patients empowerment, adherence to treatment and long-term BP control. In spite of all these potential advantages, however, cuffless BP devices have to face specific accuracy issues, which would need refinement of specific validation protocols aimed at testing the need of individual calibration, the stability of measurements after calibration and the device actual ability to track BP changes before they might be recommended for clinical use.

Pressure changes in tapered and cylindrical shaped cuff after extension of head and neck: A randomized controlled trial.

The proper cuff pressure of endotracheal tube (ET) plays an important role in sealing the airway and preventing airway complications during mechanical ventilation. The ET cuff shape affects the cuff pressure after positional change. To investigate cuff pressure between tapered and cylindrical cuff after extension of head and neck during nasal endotracheal intubation. In a randomized clinical trial, 52 patients were randomized to one of two groups: cylindrical cuff or Tapered cuff. Cuff pressure with 22 cmH2O was applied to patients in the neutral position. After extension of head and neck, the cuff pressure was evaluated again and readjusted to 22 cmH2O. In addition, the extent of cephalad migration of ET tip was assessed and postoperative airway complications such as sore throat, and hoarseness were measured. The cuff pressure was higher in the tapered cuff (28.7 ± 1.0 cmH2O) than in the cylindrical cuff (25.5 ± 0.8 cmH2O) after head and neck extension (P < 0.001). The extent of cephalad migration of tube tip was greater in TaperGuard ET (18.4 ± 2.2 mm) than in conventional ET (15.1 ± 1.2 mm) (P < 0.001). The incidence of postoperative airway complications was comparable between two groups. After head and neck extension, the cuff pressure and the extent of cephalad migration of ET was greater in tapered cuff than in cylindrical cuff during nasal intubation, respectively.

A Tapered Cuff Tracheal Tube Decreases the Need for Cuff Pressure Adjustment After Surgical Retraction During Anterior Cervical Spine Surgery: A Randomized Controlled, Double-Blind Trial.

BackgroundSurgical retraction to expose the vertebrae during anterior cervical spine surgery increases tracheal tube cuff pressure and may worsen postoperative sore throat and dysphonia. This randomized double-blind study investigated the effect of cuff shape on intraoperative cuff pressure and postoperative sore throat and dysphonia.MethodsEighty patients were randomized to tracheal intubation with a tapered cuff or a conventional cylindrical high-volume low-pressure cuff (control) during anesthesia. Intraoperative cuff pressures were compared. The primary outcome was the incidence of pressure adjustment needed when the cuff pressure increased to > 25 mm Hg after surgical retraction. The secondary outcome was the incidence of postoperative sore throat and dysphonia.ResultsThe incidence of pressure adjustment after surgical retraction was significantly lower in the tapered group than in the control group (13% vs. 48%; P = 0.001; relative risk reduction, 74%). The median [interquartile range (IQR)] cuff pressure (mm Hg) was significantly lower for the tapered cuff than for the control cuff before surgical retraction [9 (7–12) vs. 12 (10–15); P < 0.001] and after retraction [18 (15–23) vs. 25 (18–31); P = 0.007]. The median (IQR) postoperative dysphonia score assessed by a single speech-language pathologist was lower in the tapered group than in the control group [4 (3–6) vs. 5.5 (5–7); P = 0.008].ConclusionA tapered cuff tracheal tube decreased the need for the adjustment of cuff pressure after surgical retraction during anterior cervical spine surgery, thereby avoiding intraoperative pressure increase. It also has a better outcome in terms of dysphonia.Clinical Trial Registration[www.clinicaltrials.gov], identifier [NCT04591769].

A Literature Review of Factors Related to Postoperative Sore Throat.

Postoperative sore throat can occur as a complication in patients who have undergone surgery under general anesthesia. The incidence of postoperative sore throat ranges from 12.1% to 70%, and its effects include damage to the epithelium and mucosal cells caused by airway securement, damage to the vocal cords, congestion, blood clots, and factors such as an inappropriately large tube, cuff shape, cuff pressure, and airway securement. Notably, there are individual differences in pain thresholds, and the sensation of pain is affected by mental states, such as anxiety, and varies from person to person. Therefore, we conducted a literature review using PubMed to clarify patient factors related to the development of postoperative sore throat. The extracted keywords were “postoperative sore throat,” “anesthesia,” and “patient factors.” We found 16 articles that met our search criteria. We expanded the search period and retrieved 19 cases from 1990 to 2020. We also included references that were judged to be closely related to the list of citations of the retrieved references. The study designs included were randomized controlled trials, clinical trials, meta-analyses, reviews, and systematic reviews. The results showed that female sex, smoking, and age were the most common patient factors. However, we could not find any literature that studied the relationship between postoperative sore throat and mental states such as anxiety.

Endotracheal tube cuff pressure: An overlooked risk

The endotracheal tube (ETT) cuff's principal function is to implement proper tracheal sealing at a pressure high enough to prevent both gas leak and fluid aspiration, and low enough to maintain tracheal perfusion. Clinicians are often concerned primarily with the volume of air required to inflate an ETT cuff. However, the most important factor is how much pressure will be exerted on the tracheal mucosa when the cuff is properly distended. Cuff over-inflation complications range from sore throat to tracheal ischemia with tracheal rupture and fistula formation. The ideal ETT cuff pressure has not been defined with a high degree of certainty however most anesthesiologists generally recommend a target pressure of 20 to 30 cmH2O. Although trachea-gas sealing can be achieved at ETT cuff pressure of 20 cmH2O, microaspiration can occur at a cuff pressure of 60 cmH2O. Since the introduction of cuffed ETT in the mid- 20th century, several modifications in the cuff's shape and material have been done to address these challenges. It has been proven that the pressure within the inflated cuff is a dynamic process. As such, various clinical factors will significantly impact the pressure reading. Thus, continuous regulation of ETT cuff pressure should be routine practice. Our review included 158 articles that addressed the background into the development of cuffed ETT, function and anatomy of the ETT cuff system, cuff pressure and sealing characteristics, ETT cuff pressure regulation, microaspiration, and factors affecting ETT cuff pressure.&#x0D; Key words: Endotracheal Tube; Cuff pressure; Microaspiration&#x0D; Citation: Al-metwalli RR, Fallatah SM, Alghamdi TM. Endotracheal tube cuff pressure: An overlooked risk. Anaesth. pain intensive care 2021;25(1):88-97;&#x0D; DOI: 10.35975/apic.v25i1.1445&#x0D; Received: 2 November 2020, Reviewed: 24 December 2020, Accepted: 1 January 2021&#x0D;

Investigation of wrist joint cuff material and shape in a new pneumatic-type dynamic splint for wrist joint disease : Using blood flow and electromyography

Investigation of wrist joint cuff material and shape in a new pneumatic-type dynamic splint for wrist joint disease : Using blood flow and electromyography

Clinical Efficacy of Ambu Aura Gain vs Laryngeal Mask Airway Proseal in Paediatric Patients Undergoing Elective Surgery under General Anaesthesia: A Randomised Controlled Trial

Introduction: Laryngeal Mask Airway ProSeal (LMA-P) is considered a gold standard among second generation supra glottis airway devices as an effective, safe and reusable ventilatory device. Ambu Aura Gain (AAG) is a newer single use second generation airway device with a soft inflatable cuff and preformed shape. Aim: To compare the clinical effectiveness and oral pharyngeal seal pressures between LMA ProSeal and AAG in children receiving controlled ventilation. Materials and Methods: This study was conducted in 100 paediatric patients in age group of 1 to 12 years, weighing 5 to 30 kg, fulfilling the criteria of American Society of Anaesthesiologists (ASA) Physical Status I and II and undergoing elective surgical procedures. Patients were randomised into two groups. Secondary objective was to compare the ease, success and total time for achieving effective ventilation and ease of placement of gastric tube and fibreoptic visualisation of glottis view in both the groups. Quantitative variables were compared using Independent t-test/Mann-Whitney Test and qualitative variables were compared using Chi-Square test/Fisher’s-Exact test. Results: The median (IQR) Oropharyngeal Seal Pressure (OSP) was much higher with AAG 22 cm (21-23) of water as compared to LMA ProSeal 21 cm (20-22) of water and the difference was statistically significant (p-value &lt;0.0001). Time taken for achieving effective ventilation {median (IQR)} was significantly less with AAG {18 (17-19) seconds} as compared to that with LMA ProSeal {19 (18-20) seconds} (p=0.0005). The two devices were comparable in terms of success and ease of insertion of device, ease of placement of gastric tube and fibreoptic visualisation of glottis view. Conclusion: The study suggests that AAG, a single use device, is a useful substitute to LMA ProSeal to ventilate paediatric patients undergoing elective surgical procedures.

Correlation of patient characteristics with arm and finger measurements in Asian parturients: a preliminary study

BackgroundAccurate blood pressure (BP) measurement depends on appropriate cuff size and shape in relation to the arm. Arm dimensions outside the recommended range of cuff sizes or trunco-conical arms may result in inaccurate BP measurements. Measuring BP using finger cuffs is a potential solution. Arm cuff size is based on mid-arm circumference (MAC), and trunco-conicity is quantified by conicity index. We aimed to determine the correlation of MAC, body mass index (BMI), and weight with conicity index.MethodsA prospective cohort study was conducted in the KK Women’s and Children’s Hospital where third trimester parturients scheduled for cesarean delivery were recruited after obtaining informed consent. Parturients were asked to rate their experience with time taken to obtain BP readings, cuff popping off during measurement, need to move the cuff from the upper arm to lower arm or leg, and need to change to a different cuff. Our primary outcome was the correlation between MAC and conicity index, calculated using Pearson’s correlation. The correlation between BMI and weight with conicity index was also determined.ResultsWe enrolled 300 parturients. Moderate correlation was found between left MAC and left conicity index (r = 0.41, 95% CI 0.32 to 0.51), and right MAC and right conicity index (r = 0.39, 95% CI 0.29 to 0.48). Weight (r = 0.35 to 0.39) and BMI (r = 0.41 to 0.43) correlated with conicity index in this study. MAC of 1 parturient fell outside the recommended range for arm cuffs, but all parturients fit into available finger cuffs. Obese parturients had increased problems with arm cuffs popping off and needing a change of cuff.ConclusionsBMI better correlated with conicity index compared to MAC or weight. Standard finger cuffs were suitable for all parturients studied and may be a suitable alternative.Trial registrationClinicaltrials.gov NCT04012151. Registered 9 Jul 2019

Implementation of the TaperGuard\u2122 endotracheal tube in an unselected surgical population to reduce postoperative pneumonia

BackgroundEndotracheal tube (ETT) designs to decrease the risk of ventilator associated pneumonia (VAP) include supraglottic suctioning, and/or modifications of the cuff shape. The TaperGuard™ ETT has a tapered, polyvinylchloride cuff designed to reduce microaspiration around channels that form with a standard barrel-shaped cuff. We compared risk of postoperative pneumonia using the TaperGuard™ ETT and the standard ETT in surgical patients requiring general anesthesia with endotracheal intubation.MethodsWe used an interrupted time-series design to compare endotracheal intubation using the TaperGuard™ ETT (intervention cohort), and a historic cohort using the standard ETT (baseline cohort), among surgical patients requiring hospital admission. We compared the incidence of postoperative pneumonia in the intervention and baseline cohorts. Data were collected from the electronic health record and linked to patient-level data from National Surgical Quality Improvement Project. Additionally, we performed secondary analyses in a subgroup of patients at high risk of postoperative pneumonia.Results15,388 subjects were included; 6351 in the intervention cohort and 9037 in the baseline cohort. There was no significant difference in the incidence of postoperative pneumonia between the intervention cohort (1.62%) and the baseline cohort (1.79%). The unadjusted odds ratio (OR) of postoperative pneumonia was 0.90 (95% CI: 0.70, 1.16; p = 0.423) and the OR adjusted for patient characteristics and potential confounders was 0.90 (95% CI: 0.69, 1.19; p = 0.469), comparing the intervention and baseline cohorts. There was no a priori selected subgroup of patients for whom the use of the TaperGuard™ ETT was associated with decreased odds of postoperative pneumonia relative to the standard ETT. Hospital mortality was higher in the intervention cohort (1.5%) compared with the baseline cohort (1.0%; OR 1.46, 95% CI: 1.09, 1.95; p = 0.010).ConclusionsThe broad implementation of the use of the TaperGuard™ ETT for intubation of surgical patients was not associated with a reduction in the risk of postoperative pneumonia. In the setting of a low underlying postoperative pneumonia risk and the use of recommended preventative VAP bundles, further risk reduction may not be achievable by simply modifying the ETT cuff design in unselected or high-risk populations undergoing inpatient surgery.Trial registrationClinicalTrials.gov, ID NCT02450929.

Pathogenesis-Targeted Preventive Strategies for Multidrug Resistant Ventilator-Associated Pneumonia: A Narrative Review.

Ventilator-associated pneumonia (VAP) is the most common hospital-acquired infection in the intensive care unit (ICU), accounting for relevant morbidity and mortality among critically ill patients, especially when caused by multidrug resistant (MDR) organisms. The rising problem of MDR etiologies, which has led to a reduction in treatment options, have increased clinician’s attention to the employment of effective prevention strategies. In this narrative review we summarized the evidence resulting from 27 original articles that were identified through a systematic database search of the last 15 years, focusing on several pathogenesis-targeted strategies which could help preventing MDR-VAP. Oral hygiene with Chlorhexidine (CHX), CHX body washing, selective oral decontamination (SOD) and/or digestive decontamination (SDD), multiple decontamination regimens, probiotics, subglottic secretions drainage (SSD), special cuff material and shape, silver-coated endotracheal tubes (ETTs), universal use of gloves and contact isolation, alcohol-based hand gel, vaporized hydrogen peroxide, and bundles of care have been addressed. The most convincing evidence came from interventions directly addressed against the key factors of MDR-VAP pathogenesis, especially when they are jointly implemented into bundles. Further research, however, is warranted to identify the most effective combination.

Non-Pharmacological Interventions to Prevent Ventilator-Associated Pneumonia: A Literature Review.

Ventilator-associated pneumonia (VAP) is a well-known complication of invasive mechanical ventilation in critically ill patients. The presence of an endotracheal tube (ETT) is one of the major culprits for VAP development: air flow moves pathogens toward the distal airways, while clearance of the trachea is blunted due to reduced tracheal ciliary movement and impaired cough. Several measures are recognized as being useful to prevent VAP, and these are usually grouped in a VAP bundle (ie, avoiding intubation or re-intubation whenever possible; head of bed elevation; hand hygiene; shortening ventilation through sedation interruptions, spontaneous breathing trials, or thromboembolic prophylaxis). However, other interventions have been proposed to reduce VAP rate; some of these interventions have been reported in large clinical trials to be effective, some have been evaluated in small observational studies, and still others at a pre-clinical stage. Some strategies aim to improve the ETT design via a subglottic drainage system, with treatment of the ETT surface to reduce pathogen activity, or by modification of the cuff shape or cuff material to provide a better seal. Another proposed strategy is improving airway care through control of cuff pressure, cleaning the ETT, or use of closed suction systems. Other interventions target a patient's position in the bed to reduce aspiration of digestive content in the airways, or the use of probiotics to modulate gastric flora. Some of these measures are supported by strong evidence, but the impact on relevant outcomes such as duration of ventilation or mortality, as well as cost-benefit ratio, is still unclear, resulting in lack of widespread use.

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.

Relationship of the Shape of Subacromial Spur and Rotator Cuff Partial Thickness Tear.

BackgroundThe present study was undertaken to evaluate the relationship between location of the rotator cuff tear and shape of the subacromial spur.MethodsTotally, 80 consecutive patients who underwent arthroscopic repair for partial thickness rotator cuff tear were enrolled for the study. Bigliani’s type of the acromion, type of subacromial spur, and location of partial thickness tear of the rotator cuff were evaluated using plain X-ray and magnetic resonance imaging. We then compared the groups of no spur with spur, and heel with traction spur.ResultsOf the 80 cases, 25 cases comprised the no spur group, and 55 cases comprised the spur group. There was a significant difference in type of tear (p=0.0004) between these two groups. Bursal side tears were significantly greater (odds ratio=6.000, p=0.0007) in the spur group. Subjects belonging to the spur group were further divided into heel (38 cases) and traction spur (17 cases). Comparing these two groups revealed significant differences only in the type of tear (p=0.0001). Furthermore, the heel spur had significantly greater bursal side tear (odds ratio=29.521, p=0.0005) as compared to traction spur.ConclusionsThe heel spur is more associated to bursal side tear than the traction spur, whereas the traction spur associates greater to the articular side tear.

Perioperative Noninvasive Blood Pressure Monitoring.

The most commonly monitored variable for perioperative hemodynamic management is blood pressure. Several indirect noninvasive blood pressure monitoring techniques have been developed over the last century, including intermittent techniques such as auscultation (Riva-Rocci and Korotkoff) and oscillometry (Marey) and continuous techniques. With the introduction of automated noninvasive blood pressure devices in the 1970s, the oscillometric technique quickly became and remains the standard for automated, intermittent blood pressure measurement. It tends to estimate more extreme high and low blood pressures closer to normal than what invasive measurements indicate. The accuracy of the oscillometric maximum amplitude algorithm for estimating mean arterial pressure is affected by multiple factors, including the cuff size and shape, the shape of the arterial compliance curve and arterial pressure pulse, and pulse pressure itself. Additionally, the technique typically assumes a consistent arterial compliance and arterial pressure pulse, thus changes in arterial compliance and arrhythmias that lead to variation in the pressure pulse can affect accuracy. Volume clamping, based on the Penaz principle, and arterial tonometry provide continuous tracking of the arterial pressure pulse. The ubiquitous use of blood pressure monitoring is in contrast with the lack of evidence for optimal perioperative blood pressure targets.

Modification of Tracheal Cuff Shape and Continuous Cuff Pressure Control to Prevent Microaspiration in an Ex Vivo Pig Tracheal Two-Lung Model.

Microaspiration of subglottic secretions plays a pivotal role in ventilator-associated pneumonia. Impact of endotracheal tube cuff material and shape on tracheal sealing performance remains debated. The primary objective was to compare the tracheal sealing performance of polyvinyl chloride tapered, cylindrical and spherical cuffs. Secondary objectives were to determine the impact of continuous cuff pressure control on sealing performance and pressure variability. Prospective randomized ex vivo animal study. French research laboratory. Seventy-two ex vivo pig tracheal two-lung blocks. Blocks were randomly intubated with cylindrical (n = 26), tapered (n = 24), or spherical (n = 22) polyvinyl chloride endotracheal tube cuffs. Two milliliter of methylene blue were instilled above the cuff to quantify microaspirations, and lungs were ventilated for 2 hours. Continuous cuff pressure control was implemented in 33 blocks. Cuff pressures were continuously recorded, and after 2 hours, a microaspiration score was calculated. Tapered cuffs improved cuff sealing performance compared with spherical cuffs with or without continuous cuff pressure control. Compared with spherical cuffs, tapered cuffs reduced the microaspiration score without and with continuous pressure control by 65% and 72%, respectively. Continuous cuff pressure control did not impact sealing performance. Tapered cuffs generated higher cuff pressures and increased the time spent with overinflation compared with spherical cuffs (median [interquartile range], 77.9% [0-99.8] vs. 0% [0-0.5]; p = 0.03). Continuous cuff pressure control reduced the variability of tapered and spherical cuffs likewise the time spent with overinflation of tapered and cylindrical cuffs. Polyvinyl chloride tapered cuffs sealing enhanced performance at the cost of an increase in cuff pressure and in time spent with overinflation. Continuous cuff pressure control reduced the variability and normalized cuff pressures without impacting sealing performance.

Effect of Endotracheal Tube Cuff Shape on Postoperative Sore Throat After Endotracheal Intubation.

Although minor, a sore throat after endotracheal intubation can adversely affect patient satisfaction and postoperative function. We compared the effects of 2 endotracheal tube cuff shapes on postoperative sore throat. One hundred ninety-one adult patients were included in the study. After induction of anesthesia, patients were randomized to endotracheal intubation with a conventional cylindrical-shaped cuff (Group C, n = 95) or a tapered-shaped cuff (Group T, n = 96). The number of intubation attempts, time to achieve endotracheal intubation, and duration of intubation were recorded. Postoperative sore throat and hoarseness were assessed at 1, 6, and 24 hours after surgery. A 0- to 100-mm visual analog scale was used to evaluate sore throat severity. The primary outcome of this study was the overall cumulative incidence of postoperative sore throat in the 24-hour evaluation period in the 2 groups. The overall incidence of postoperative sore throat was lower in Group T than in Group C (32% vs 54%; relative risk = 0.60, 95% confidence interval: 0.43-0.85; P= .003). At 6 hours after surgery, the incidence and severity of postoperative sore throat were lower in Group T compared with Group C (Bonferroni-corrected P< .05). Postoperative hoarseness also occurred less frequently in Group T compared with Group C (19% vs 37%; P= .006). Group T had lower incidence of hoarseness at 1 and 6 hours after surgery than Group C (Bonferroni-corrected P< .05), but the incidence of hoarseness at 24 hours after surgery did not differ between groups. Intubation using an endotracheal tube with a tapered cuff reduced the incidence and severity of postoperative sore throat and the incidence of hoarseness after surgery when compared with an endotracheal tube with a cylindrical cuff.

Efficacy and safety of a new elastic tourniquet cuff in total knee arthroplasty: a prospective randomized controlled study

BackgroundThe effects of cuff shape, timing of tourniquet application, and automated systems using limb occlusion pressure (LOP) have been reported to minimize the appropriate tourniquet pressure. However, studies on the raw material of the cuff itself to reduce the complications related to the tourniquet have been very rarely reported. The purpose of this study is to report the efficacy and safety of a tourniquet system with a new elastic cuff in which pressure is set with LOP in total knee arthroplasty (TKA).MethodsA total of 63 patients who underwent primary TKA for osteoarthritis were enrolled from July to December 2015. Thirty-one patients were allocated to the new elastic cuff group and 32 in the conventional cuff group. Bloodless surgical field, pain visual analog scale (VAS) on the thigh, thigh circumference, range of motion, incidence of deep vein thrombosis, and muscle enzyme level after surgery were checked and compared between the 2 groups.ResultsOnly 1 of the 31 patients in the elastic cuff group required more pressure for obtaining a bloodless surgical field, whereas 4 of the 32 patients in the conventional cuff group required more pressure to complete surgery without being disturbed by sustained bleeding. Two patients in the conventional cuff group needed treatment for blisters and bullae at the tourniquet application site. There was no difference in pain VAS score, thigh circumference, range of motion, incidence of deep vein thrombosis, and level of muscle enzyme.ConclusionsA new elastic tourniquet cuff provided a more proper bloodless surgical field with less adjustment of tourniquet pressure despite a similar level of tourniquet pressure compared to the conventional cuff and had a low incidence of skin complications on the site of tourniquet application in TKA. These benefits make it an effective and safe medical device for orthopedic surgery requiring a tourniquet, such as TKA.