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Severing of the pilot balloon of an endotracheal tube (ETT) results in cuff deflation and may lead to complications including inadequate patient ventilation, increased risk of aspiration and infection, and operating room air pollution with anesthetic gases. In situations where ETT exchange or reintubation may pose a significant risk to the patient, temporary repair of the severed cuff tubing can be helpful until it is safe to address the problem with replacing the ETT. Simple and effective repair methods can be achieved using readily available materials in the operating room, including intravenous cannulas, hypodermic syringes, and epidural clamp connectors. However, choosing which technique or method depends mainly on personal preference, equipment availability, and provider comfort and experience. We present a 12-year-old adolescent who presented for anesthetic care for extensive burn injury. During removal of the dressing around the head and face, the tubing of the pilot balloon of the ETT was inadvertently cut. Options for dealing with such problems are discussed, including techniques to allow for temporary repair and re-inflation of the deflated cuff.

We report a technique that was utilized to manage an intraoperative airway complication occurring during orthognathic surgery wherein the endotracheal tube pilot balloon was inadvertently damaged during the procedure. Readily available operating room materials were used to safely and rapidly repair the damaged endotracheal tube pilot balloon. This allowed the perioperative team to avoid emergent endotracheal tube exchange and potential airway complications.

Introduction: The cuff pressure is measured in industrial equipment, however, be valid in the craft equipment is still questioned. Objective: To evaluate the reliability of the measurement methods of cuff pressure endotracheal tubes with industrialized and handmade equipment. Method: Were analyzed 40 endotracheal tubes, two brands (Solidor and Ruschelit) and different diameter (8,0 mm and 8,5mm), inflated 20mL of air in the pilot balloon with plastic syringe and 20 mL, followed by pressure measurement device with industrial (cmH2 O) and handmade device (mmHg). After the conversion of cmH2O values for mmHg, the reliability and agreement of measurements were performed by intra-class correlation (ICC) and Bland-Altman tests, respectively, using SPSS (version 15.0) and adopting a significance level of 5% for all comparisons. Results: The data showed similarity between the different pressure equipment, brands and diameter, and demonstrated strong correlation and agreement between the methods. Tube Rus8,0mm industrial versus handmade (28.2±5.8 vs 28.4±6.2 mmHg: ICC=0.998; bias=0.20); Tube Solidor8.0mm industrial versus handmade (75.9±1.1 vs 76.4±1.2 mmHg: ICC=0.878; bias=0.40); Tube Rus8.5mm industrial versus handmade (17.1±8.8 vs 17.8±8.9 mmHg: ICC=0.999; bias=0.67); Tube Sol8.5mm industrial versus handmade (78.7±4.7 vs 78.6±4.6 mmHg: ICC=0.996; bias=-0.1). Conclusion: The high reliability and agreement presented in this study suggest that the cuff pressure gauge handmade can be used safely to evaluate the cuff pressure of the endotracheal tube.

Introduction Airway management in patients with panfacial fracture remains a challenge to anesthesiologists and surgeons. Submental intubation is an effective and less invasive alternative to tracheostomy during intraoperative airway management where orotracheal and nasotracheal intubation are not appropriate options. In addition, submental intubation allows proper access to oronasal airways and occlusion during intraoperative management. Methods The descriptive retrospective study was carried out and evaluated the outcomes of submental intubation in the management of panfacial fracture, complex maxillary or mandible fracture associated with nasal bone fracture and naso-orbito-ethmoid (NOE) fracture. The medical records of 23 patients who received submental endotracheal intubation were reviewed at UCMS College of Dental Surgery, Bhairahawa, Rupandehi, Nepal from March 2014 to December 2018. The following parameters were evaluated: mode of trauma, time required for intubation, accidental extubation, accidental perforation of the pilot balloon during its insertion, period of hospital stay, post-operative complications, such as the healing of submental scars both intraorally and extraorally. Results The submental intubation was successfully done in all patients with minimal obvious post-operative complications. The mode of trauma for majority of cases of panfacial fracture who underwent submental intubation was road traffic accident (69.56%). The mean time required for intubation was 8.43 (±0.84) minutes. No accidental extubations occurred. Accidental perforation of the pilot balloon was seen in one patient (4.35%) during tube manipulation which was managed successfully by changing the tube. The healing of submental scars was uneventful intraorally and extraorally in almost every case. The mean period of hospital stay in patients with submental intubation was 7.95 (±1.49) days. Discussion Submental intubation is an effective and safe method as it is not associated with complications of tracheostomy during management of panfacial fracture, NOE fracture and craniofacial fracture. In addition, it does not interfere with IMF during intraoperative period.

Background and objectives: Poor monitoring of tracheal tube cuff pressure may result in patient complications. The objective method of using a manometer is recommended to keep safe cuff pressure values (20‒30 cm H2O). However, as manometers are not readily available, anesthesiologists use subjective methods. We aimed to assess appropriateness of a subjective method for attaining cuff pressure and the expertise level of manometer handling among anesthesiology staff and residents in a university teaching hospital. Methods: Prospective observational study, recruiting participants that performed tracheal intubation and the subjective method for tube cuff inflation. Patients with difficult airway, larynx and trachea anatomic abnormality and emergency procedures were not included. Up to 60 minutes after tracheal intubation, an investigator registered the cuff pressure using an aneroid manometer (AMBU®) connected to the tube pilot balloon. Results: Forty-seven anesthesiologists were included in the study – 24 residents and 23 staff. Mean (SD) and medians (IQR) measured in cmH2O were, respectively, 52.5 (27.1) and 50 (30‒70). We registered 83% of measurements outside the recommended pressure range, with no difference between specialists and residents. The level of expertise with the objective method was also similar in both groups. Pressure adjustments were performed in 76.6% of cases. Conclusion: The subjective method for inflating the tracheal tube cuff resulted in a high rate of inadequate cuff pressures, with no difference in performance between anesthesiology specialists and residents.

Background Endotracheal tube cuff (ETTc) inflation pressure is usually not regarded as an important aspect during intubation. In this study, we compared measuring ETTc pressure and pilot balloon palpation method in causing post-operative airway complications. Methods Two hundred and ninety-two surgical patients requiring intubation were recruited into this prospective, double-blind, randomised controlled study. Group A patients had their ETTc initially inflated, checked by a cuff pressure gauge, recorded and then set to 25 cmH2O. Group B patients had their ETTc inflated using the pilot balloon palpation method. Patients were then followed up for post-operative sore throat, hoarseness and cough. Results The overall incidence of post-operative sore throat was 39.0% versus 75.3% (P < 0.001), hoarseness 6.2% versus 15.1% (P < 0.05) and cough 7.5% versus 21.9% (P < 0.05) in Group A and B, respectively. Group A patients experienced a significant reduction in the incidence and severity of sore throat up to 24 h post-operatively (P < 0.001), hoarseness at the first hour (P = 0.004) and cough at first and 12 h post-operatively (P = 0.002). Conclusion Adjusting the ETTc pressure to 25 cmH2O reduces post-operative sore throat, hoarseness and cough compared to pilot balloon palpation method.

BackgroundThe common causes of failure to inflate the lungs after placement of an endotracheal tube include mechanical obstruction of the tube by tight gauzes, tongue blade, tube kinking, patient biting on the tube, obstruction of the lumen by blood or foreign body, bronchospasm, haemothorax, tension pneumothorax or equipment malfunction.Case presentationWe report a case of complete airway obstruction due to herniation of the pilot inflation line into the lumen at the proximal end of a reinforced tube when the tracheal cuff was inflated. Prior to use, the endotracheal tube was tested and functioned normally. The patient was uneventfully reintubated with a new endotracheal tube. With the endotracheal tube, device problems often involve the pilot balloon and cuff assembly and leaks are more common.ConclusionThis case report highlights an unusual cause of complete proximal lumen obstruction due to a manufacturing defect which could have caused a critical incident in the theatre.

Background We evaluated the endotracheal tube cuff pressure (Pcuff) changes during pneumoperitoneum for laparoscopic cholecystectomy and the correlations between body mass index (BMI), pneumoperitoneum time, and Pcuff changes. Methods Total 60 patients undergoing laparoscopic cholecystectomy were allocated to either a study group (BMI ≥ 25 kg/m2) or a control group (BMI < 25 kg/m2). The endotracheal intubation was performed with a high-volume low-pressure cuffed oral endotracheal tube. A manometer was connected to the pilot balloon using a 3-way stopcock and the cuff was inflated. The change in Pcuff was defined as the difference between the pressure just before intra-abdominal CO2 insufflation and the pressure before CO2 desufflation. Results Pcuff increased to 5.3 ± 3.6 cmH2O in the study group and 5.7 ± 5.4 cmH2O in the control group. There was no significant difference between two groups. While BMI was not correlated with change in Pcuff (r = 0.022, p = 0.867), there was a significant correlation between change in Pcuff and the duration of pneumoperitoneum (r = 0.309, p = 0.016). Conclusion The change in Pcuff was not affected by BMI and was significantly correlated with pneumoperitoneum time. We recommend regular measurement and adjustment of Pcuff during laparoscopic surgery.

In the early part of the 20th century, tracking a pilot balloon from the ground with an optical theodolite was one of the few methods that was able to provide information from the upper air. One of the most significant sources of error with this method, however, was involved in calculating the balloon height as a function of time, a calculation dependent on the ascent rate which was traditionally taken to be constant. This study presents a new thermodynamic model which allows us to compute the thermal jump between the surrounding environment and the lifting gas as a function of different parameters such as the atmospheric temperature lapse rate or the physical characteristics of the balloon. The size of the thermal jump and its effect on the ascent rate is discussed for a 30 g pilot balloon, which was the type used at the Ebro Observatory (EO) between 1952 and 1963. The meridional and zonal components of the wind profile from ground level up to 10 km altitude were computed by applying the model using EO digitized data for a sample of this period. The obtained results correlate very well with those obtained from the ERA5 reanalysis. A very small thermal jump with a weak effect on the computed ascent rate was found. This ascent rate is consistent with the values assigned in that period to the balloons filled with hydrogen used at the Ebro Observatory and to the 30 g balloons filled with helium used by the US National Weather Service.

To prevent endotracheal tube-related barotrauma or leakage, the intracuff pressure should be adjusted to 20–30 cm H2O. However, changes in the nasotracheal tube intracuff pressure relative to neck posture are unclear. In this study, we investigated the effect of head and neck positioning on nasotracheal tube intracuff pressure. Fifty adult patients with nasotracheal tubes who were scheduled for surgery under general anesthesia were enrolled. Following intubation, intracuff pressure was measured by connecting the pilot balloon to a device that continuously monitors the intracuff pressure. Subsequently, the intracuff pressure was set to 24.48 cm H2O (=18 mmHg) for the neutral position. We recorded the intracuff pressures based on the patients’ position during head flexion, extension, and rotation. The initial intracuff pressure was 42.2 cm H2O [29.6–73.1] in the neutral position. After pressure adjustment in the neutral position, the intracuff pressure was significantly different from the neutral to flexed (p &lt, 0.001), extended (p = 0.003), or rotated (p &lt, 0.001) positions. Although the median change in intracuff pressure was &lt, 3 cm H2O when each patient’s position was changed, overinflation to &gt, 30 cm H2O occurred in 12% of patients. Therefore, it is necessary to adjust the intracuff pressure after tracheal intubation and each positional change.

Dural sinus stenting is an increasingly recognized intervention for the treatment of lateral sinus stenosis. This procedure can be challenging in tortuous anatomy and in the presence of intraluminal septa because of poor trackability and crossability of long sheath commonly used for stenting. We report a technique using a pilot angioplasty balloon positioned at the distal end of the long sheath that improves its navigability in dural sinuses and facilitated the intervention.

This paper uses rawinsondes and pilot balloon data from the 2004 North American Monsoon (NAM) Experiment, as well as satellite-based products and reanalysis datasets that span 1982 to 2018, to anal...

Background The use of cuffed endotracheal tubes (ETTs) in paediatric critical care has become widespread with the development of high volume – low pressure cuffs which require significantly lower sealing pressure than traditional ETTS. There remains a risk of over inflation which can impair tracheal capillary perfusion causing pressure necrosis of the surrounding fragile epithelium potentially resulting in permanent upper airway damage such as sub-glottic stenosis. Cuff pressure can vary over time therefore careful monitoring is vital to ensure the pressure remains within a safe range. Objectives Connecting a manometer to the pilot balloon is one method to monitor cuff pressure. A prior study demonstrated that connecting a manometer caused a drop in pressure giving a falsely low readings. We hypothesised that pre-pressuring the manometer would result in accurate cuff pressure readings enabling detection of dangerously high pressures. Methods An airway model was intubated with Halyard size 3.0 micro-cuff ETT. Using a commercially available manometer, a three way tap and syringe the cuff was inflated to a set pressure in increments of 1 cm H2O between 0 and 40 cm H2O. The manometer was then connected to the pilot balloon to check the pressure using 3 methods: Control 1) Manometer connected directly to the pilot balloon (no tubing used therefore pressure in the system = 0 cm H2O) Control 2) Manometer connected to the pilot balloon via extension tubing with 3 way tap and syringe in circuit (pressure in tubing and manometer system = 0 cm H2O) Test 3) Manometer connected to the pilot balloon via extension cable with 3 way tap and syringe in circuit with the entire circuit pre-pressurised to 20 cmH2O before connecting Set-up 2) was used as a control to show how the tubing and 3 way tap affected the readings. For each method three measurements were performed at every 1 cm H2O increment and the average reading was taken. Results Using method 1 the average manometer reading was significantly lower than the pre-set cuff pressure for example pre-set pressures of 20 & 40 cm H2O read only 5.3 and 8 cm H2O respectively. Using method 2 the average readings dropped even further from the pre-set pressure. Using method 3 with the manometer pre-pressurised to 20 cm H2O the reading dropped if the cuff pressure was ≤19 cm H2O and increased if the cuff pressure was ≥21 cm H2O. A pre-set pressure of 0 gave a reading of 11 cm H2O, 10 read as 17.7 cm H2O, 30 read as 20 cm H2O and 40 read as 21.3 cm H2O. Conclusions The results indicate that the intervention of connecting a manometer renders the reading inaccurate. This disparity is due to the dead space in the manometer and also the tubing as shown by the lower readings from method 2. The hypothesis of filling the dead space by pre-pressurising the manometer system did not result in more accurate readings as the pressure merely equalised across the system. Therefore the only way to ensure cuff pressures are not dangerously high is to deflate the cuff and use the 3-way tap system or cuff inflator to inflate to a safe pressure.

BACKGROUND Sore throat is a common complication after Laryngeal Mask Airway Supreme (SLMA) insertion. OBJECTIVE The aim of this study was to determine whether a new SLMA insertion technique (not removing the pilot tube blocker before insertion) lowers the incidence of sore throat in the postanaesthesia care unit (PACU). DESIGN A prospective, single-centre, parallel randomised controlled trial. SETTING Operating room and PACU at a hospital in China from June to September 2019. PATIENTS Four hundred and eight patients aged 18 to 65 years with American Society of Anaesthesiologists physical status class I or II who were scheduled for elective surgery requiring anaesthesia and SLMA insertion. INTERVENTIONS Leaving the blocker at the end of the pilot tube in situ (this blocker keeps the valve open and the balloon remains partially inflated but will deflate with pressure) or removing the blocker and actively deflating the cuff before SLMA insertion. MAIN OUTCOME MEASURES The primary outcome was the incidence of postoperative sore throat in the PACU. The secondary outcomes included sore throat severity (Prince Henry Hospital Pain Score), first-attempt success rate, ease of insertion, time to successful SLMA insertion, oropharyngeal leak pressure, grade of view on fibreoptic bronchoscopy (indicating the accuracy of SLMA positioning) and adverse events. RESULTS The incidence of sore throat was 33/204 (16.2%) in the nonremoval group, and 65/204 (31.9%) in the removal group (P

Objective To present a novel urethral catheter design with a pilot balloon to reduce intraurethral retention balloon inflation pressures and to provide a visual alert during catheter placement. Methods We manufactured our pilot balloon prototype from both molded and extruded silicone components. Various pilot balloon thicknesses were tested in order to determine the ideal compliance. We studied the filling pressures of the retention balloon of our prototype in a mechanical urethral model. The prototype catheter was then tested in ex-vivo human penis specimens obtained from gender affirming surgery and changes in the size of the retention balloon were measured under fluoroscopy. Results The thickness of the pilot balloon was directly related to the inflation pressure of the retention balloon in the mechanical urethral model. The thickness chosen for the pilot balloon in our prototype was based on a retention balloon pressure of 70 kPa. In the ex-vivo human penis model, the presence of the pilot balloon resulted in a 40% reduction in the cross-sectional area of the retention balloon compared to a standard urinary catheter. Conclusion The prototype urinary catheter appears to decrease the filling pressure and size of an improperly positioned retention balloon inside a urethra. This can potentially reduce the risk of iatrogenic urethral catheter injuries. In addition, the prototype urinary catheter may act as a visual warning sign for the healthcare practitioner.

The Integrated Global Radiosonde Archive (IGRA) is a collection of historical and near-real-time radiosonde and pilot balloon observations from around the globe. Consisting of a foundational dataset of individual soundings, a set of sounding-derived parameters, and monthly means, the collection is maintained and distributed by the National Oceanic and Atmospheric Administration’s National Centers for Environmental Information (NCEI). It has been used in a variety of applications, including reanalysis projects, assessments of tropospheric and stratospheric temperature and moisture trends, a wide range of studies of atmospheric processes and structures, and as validation of observations from other observing platforms. In 2016, NCEI released version 2 of the dataset, IGRA 2, which incorporates data from a considerably greater number of data sources, thus increasing the data volume by 30%, extending the data back in time to as early as 1905, and improving the spatial coverage. To create IGRA 2, 40 data sources were converted into a common data format and merged into one coherent dataset using a newly designed suite of algorithms. Then, an overhauled version of the IGRA 1 quality-assurance system was applied to the integrated data. Last, monthly means and sounding-by-sounding moisture and stability parameters were derived from the new dataset. All of these components are updated on a regular basis and made available for download free of charge on the NCEI website.

Background: The importance of monitoring and controlling endotracheal tube cuff (ETTc) pressure in reducing larynge-otracheal injuries and intubation-related respiratory compli-cations has been previously investigated by several authors. However, little is known about the role of controlling ETT cuff pressure in minimizing transient voice changes following endotracheal intubation.Aim of the Study: The aim of this study was to investigate the importance of monitoring and controlling ETTc pressure in reducing voice disorders after endotracheal intubation.Patients and Methods: Fifty patients in the age between 18-50 years, undergoing middle ear surgery were enrolled into the study. Patients were randomized by means of individ-ually prepared envelopes to either the control group (n=25), without measuring ETTc pressure, or the study group (n=25), with ETTc pressure measurement. All patients were examined pre-operatively to determine baseline values, 24 hours after surgery and 1 week post-operatively. Phoniatric examination included auditory perceptual assessment, videolaryngoscopy and acoustic analysis of voice. Statistical analysis included the arithmetic mean, Standard Deviation (SD), standard error, hypothesis student's "t" and Spearman's rank-order correlation tests. p-values

BACKGROUND Endotracheal tube (ETT) cuffs are designed to seal the lower airway for precise ventilation and to protect against ingress of pathogens from the pharyngeal space. Therefore, a minimal continuous cuff pressure must be maintained. Aim of this study was to analyse the course of cuff pressure in an in-vitro model during manual cuff pressure control manoeuvres. METHODS An artificial trachea was intubated with an appropriately sized ETT and cuff pressure set to 20 cm H O. Thirty-two experienced ICU nurses each performed six cuff pressure control manoeuvres (three times in two different ETTs) using a manual cuff pressure manometer. Course of cuff pressure from connecting the manometer to disconnecting it from the cuff pilot balloon was recorded using a pressure transducer. RESULTS There were 190 cuff pressure control manoeuvres suitable for analysis. In all control manoeuvres a cuff pressure below 20 cm H O was noted. In 20.0% of the control manoeuvres the cuff pressure dropped below 10 cm H O. Cuff pressure drops were mainly caused by initially connecting the manometer to the pilot balloon, less frequently by manipulating the pressure gauge of the manometer. Disconnecting the manometer after the control manoeuvre caused a cuff pressure drop in 78.1% of cases, contributing to a final cuff pressure below 20 cm H O in 31.3% of control manoeuvres. CONCLUSION Routine manual cuff pressure control manoeuvres in ETT cuffs result in considerable cuff pressure drops. This may have an impact on silent aspiration of pharyngeal contents passing along the cuff into the lower airway.

The pilot balloon palpation (or 'finger-pressure') method is still widely used to assess the endotracheal tube cuff inflation, despite consistent evidence of its poor sensitivity in recognizing cuff overinflation. It was recently speculated that this may be related to the lower wall tension (due to the smaller radius) of the pilot balloon as compared with the cuff, according to Laplace's law. To verify this hypothesis and, secondarily, to assess whether the use of a 'large' pilot balloon (identical to the cuff) increases the reliability of this technique, 62 anesthetists (41 experienced anesthesiologists and 21 residents) were asked to estimate the pressure of a cuff inflated to 88 mmHg into a simulated trachea by feeling both a usual and a modified 'large' pilot balloon. A similar test was repeated at 40 mmHg. After palpation of the usual pilot balloon, only 35% of participants (49% of experienced anesthesiologists and 10% of residents) recognized considerable overinflation (88 mmHg), as compared with 87% of participants (95% of experienced anesthesiologists and 71% of residents) after palpation of the 'large' pilot balloon. Moreover, 89% of participants (85% of experienced anesthesiologists and 95% of residents) believed that pressure was higher in the 'large' balloon than in the normal one. However, only 32% of participants (51% of experienced anesthesiologists and none of residents) recognized slight overinflation (40 mmHg) after feeling the 'large' balloon. The pilot balloon size affects the sensitivity of the 'finger-pressure' technique, but it remains poorly reliable with a larger pilot balloon.

Introduction: Filling tracheal tube cuff (TTC) after intubation is necessary to provide a safe airway in intubated patients. On the other hand, excessive increase or decrease in the pressure of TTC’s balloon leads into the dangerous complications such as necrosis and/or aspiration. Accordingly, in the present study, we tried to evaluate the most two common fixed volume and pilot balloon palpitation methods to control TTC pressure. Methods: In a prospective cross-sectional study that was carried out in the emergency department of Tabriz Imam Reza hospital upon 194 patients who needed intubation and from April 2015 to June 2016. The patients were randomly allocated into two equal groups. For the first the Pilot Balloon Palpation technique and for the second group 10 cc fixed volume cuff filling technique was assigned. After that, the pressure was checked with manometer and data were analyzed using SPSS software. Results: TTC pressure average in fixed volume group was 44.96±21.77 cmH2O and for palpation group, it was 118.15±22.15 cmH2O. There was a meaningful difference between two groups in terms of cuff inside pressure (P value

Context: Since the first sterling tracheostomy cannula was developed, in the late 1800's, and some modernization has occurred, there have been several reports on flaws surrounding their care. Objetive: Provide a comprehensive review about tracheostomy cannulas. Methods: A systematic search of the PubMed and Medline databases was conducted on closed drainage system using the following keyword combination: tracheostomy AND cannula. Results: From eight hundred eight-three articles retrieved after our preliminary search, 17 articles were chosen for final analysis. Representative schemes were drawn to better understanding of the three distinguished materials types and ten different components (faceplate, cannula, radiopaque line in the cannula, inner cannula, universal hub 15mm, pressure line, pilot balloon, cuff, subglottic aspiration system, obturator), as well as their concerns. Conclusions: Knowing and understanding tracheostomy cannulas. particularities may imply in a better approach to the patients, and in minimizing institutional costs.

Tracheostomy is a weaning technique in patients requiring prolonged ventilation. During this period, complications like tube blockage, fracture of the tracheostomy tube, or cuff rupture can occur. Fracture of the tracheostomy tube can result in the distal end of the tube being dislodged further down the trachea, leading to airway obstruction and hypoxia. We report fracture of a tracheostomy tube in which the distal end was removed, using the inflation line of the pilot balloon to pull out the broken end of the tracheostomy tube.

Submental intubation is the preferred type of intubation in patients with complex maxillofacial fractures where oral or nasal intubation cannot be performed. It is also less invasive than tracheostomy in securing the airways. We report a case where an inadvertent strangulation of inflation line of the pilot balloon resulted in inadequate ventilation during submental intubation.

Introduction Mishandled endotracheal cuff pressure may either make ventilation difficult or cause damage to the airway. Therefore, the aim of this audit was to assess the knowledge about endotracheal cuff pressure monitoring with a manometer and manual palpation of pilot balloon among critical care providers. Methods This audit includes 150 critical care providers having experience of handling endotracheal tube (ETT) cuff at critical care area of National Institute of Cardiovascular Diseases (NICVD), Karachi from April 2017 to June 2017. Knowledge about endotracheal cuff pressure monitoring with the manometer and deleterious effects of mishandled ETT cuff was assessed using a self-reported questionnaire. Enrolled healthcare providers were asked to palpate the patient and cuff pressure was recorded and categorized. Results Out of 150 participants, 66 (44.0%) were doctors. Only 46 (30.67%) participants had prior knowledge about ETT cuff manometer and 110 (73.33%) had never used a manometer. Similarly only 42 (28.0%) had knowledge of hazardous effects of mishandled ETT cuff. Kappa coefficient of 0.155 with p=0.015 showed significant yet low agreement between participant prediction and the actual amount of air in cuff balloon. Agreement level was comparatively higher for staff as compared to doctors with a Kappa coefficient of 0.210 (p=0.018) vs. 0.133 (p=0.099). Conclusion In this study of knowledge and practice of ETT tube cuff pressure monitoring, we observed low levels of knowledge (30.67%), poor adherence to standard practice (73.33%) and were able to demonstrate poor agreement (Kappa coefficient 0.155; p=0.015) between the palpation method and cuff manometer measurements for assessing cuff pressure.

Continuous insufflation of oxygen into the pilot balloon of an endotracheal tube has been documented as a viable method to fix an incompetent endotracheal tube cuff. We present a case of a large iatrogenic tracheal injury resulting from an improvised cuff leak management device. Valuable lessons are discussed to prevent similar incidents.

This study compared two methods of controlling the intracuff pressure in laryngeal mask airways. One hundred and eighty patients were randomly assigned into two groups. In the first group (n = 90), after training, the intracuff pressure was controlled using digital palpation of the pilot balloon. In the second group (n = 90), continuous manometry was used to control the intracuff pressure. An upper pressure limit of 60 cmH2 O was set. The median (IQR [range]) intracuff pressure in the palpation group was 130 (125-130 [120-130]) cmH2 O compared with 29 (20-39 [5-60]) cmH2 O in the manometry group (p < 0.001). In the palpation group, 37% of patients experienced pharyngolaryngeal complications vs. 12% in the manometry group (p < 0.001). We conclude that the digital palpation technique is not a suitable alternative to manometry in controlling the intracuff pressure in laryngeal mask airways.

Aimed at wind measurement requirement of pilot balloon observation, the double-theodolite base-line method will be discussed mainly. Then based on GJB6076-2007 and GJB 6556.3-2008, the formulas of wind vector were given and the error propagation model of double-theodolite wind measurement was founded. At last, the system and random errors of some wind measurement data were calculated and analyzed. The results showed that, the error of the double-theodolite method was mainly caused by the elevation and the azimuth angles, including measurement error and tracking error. It increases rapidly with time and height increase, and can be remarkably reduced if the error of balloon tracking is removed.

We report an unusual case of endotracheal tube failure. It was due to a manufacturing defect in the internal white plastic piece that is normally depressed by the luer-lock syringe within the blue pilot balloon. Prior to use, the endotracheal tube was tested and functioned normally. A 64-year-old patient in the intensive care unit with a history of hypertension was being mechanically ventilated after uneventful abdominal surgery. After several hours in the intensive care unit, he was noted to be suddenly no longer receiving adequate tidal volumes from the ventilator. It was found that the cuff on the endotracheal tube was not retaining air when it was filled with air from a syringe. This lead to a large “leak” around the endotracheal tube such that the intended tidal volumes set on the ventilator were not delivered to the patient. The patient was uneventfully reintubated and did well. Subsequent investigation revealed the cause to be a manufacturing defect in the internal white plastic piece that is normally depressed by the luer-lock syringe within the blue pilot balloon. Other mechanisms of cuff failure are reviewed in this case report. This case is an unusual reason for cuff failure. Illustrations supplied alert the reader how to identify the appearance of this manufacturing defect in a pilot balloon. This case illustrates the potential device malfunctions that can develop during a procedure, even when the equipment has been tested and previously functioned well. Even small defects developing in well-engineered products can lead to critical patient care emergencies.

Background Overinflation of the laryngeal mask airway (LMA) cuff may cause many of the complications associated with the use of the LMA. There is no clinically acceptable (cost effective and practical) method to ensure cuff pressure is maintained below the manufacturer's recommended maximum value of 60 cm H2O (44 mmHg). We studied the use of the intrinsic recoil of the LMA inflating syringe as an effective and practical way to limit cuff pressures at or below the manufacturer's recommended values. Methods We enrolled 332 patients into three separate groups: LMAs inserted and inflated per standard practice at the institution with only manual palpation of the pilot balloon; LMA cuff pressures measured by a pressure transducer and reduced to < 60 cm H2O (44 mmHg); and LMA intra-cuff pressure managed by the intrinsic recoil of the syringe. Results There were no statistically significant differences between the pressure transducer group and the syringe recoil group for initial cuff pressure or cuff pressure 1 hour after surgery. Both the syringe recoil group and pressure transducer group were less likely than the standard practice group to have sore throat and dysphagia 1 hour after surgery. These differences remained 24 hours after surgery. Conclusions Syringe recoil provides an efficient and reproducible method similar to manometry in preventing overinflation of the LMA cuff and decreasing the incidence of postoperative laryngopharyngeal complications.

Objectives To determine the endotracheal tube cuff pressure produced with two inflation techniques, in two brands of endotracheal tube in cats. To determine the inspiratory pressure which produces an audible leak when the intracuff pressure is 30 cmH2O. Study design Prospective, clinical, randomized study. Animals A total of 40 client-owned healthy adult cats. Methods Following induction of anaesthesia, endotracheal intubation was performed with a Parker Flex-Tip PFLP (Parker; n = 20) or Flexicare VentiSeal (Flexicare; n = 20) endotracheal tube. For each cat, the endotracheal tube cuff was inflated using two methods, minimum occlusive volume (MOV) and pilot balloon palpation (PBP). Intracuff pressure was recorded. Cuff pressure was then set at 30 cmH2O and the pressure within the breathing system when a manual breath first caused an audible leak was measured. Results PBP pressure was lower for Parker (36 ± 13 cmH2O) compared with Flexicare (45 ± 13 cmH2O, p = 0.048). MOV pressure was not different between tube types (56 ± 28 versus 66 ± 25 cmH2O for Parker and Flexicare, respectively, p = 0.247). MOV produced a higher pressure than PBP for Parker (56 ± 28 versus 36 ± 13 cmH2O, p = 0.001) and Flexicare (66 ± 25 versus 45 ± 13 cmH2O, p = 0.007). When intracuff pressure was set at 30 cmH2O, 95% of cats did not develop an audible leak until the inspiratory pressure was greater than 10 and 12 cmH2O for Parker and Flexicare tubes, respectively. Conclusions PBP produced lower cuff pressures than MOV, although both techniques produced a cuff pressure above that at which mucosal blood flow is believed to be restricted. A cuff pressure of 30 cmH2O may be sufficient to prevent audible leak in most cats if respiratory pressures are kept at 10–12 cmH2O or below. Clinical relevance To ensure a safe endotracheal tube cuff pressure, use of a specifically designed pressure gauge is recommended.

We report kinking of the pilot line of an endotracheal tube (ETT). The anesthesiologist found it difficult to deflate the ETT cuff after performing test inflation with air before intubation. We subsequently filled the pilot line with red dye and examined it from the connection with the pilot balloon to the site of entry into the ETT wall. This examination revealed stenosis of the pilot line at the entry into the ETT, making it too narrow for air to flow freely during cuff deflation. The present case emphasizes that preanesthetic checking of the ETT cuff is very important.

Despite the frequent use of endotracheal tubes in daily practice of emergency medicine, not much emphasis has been put on the measurement of cuff pressure. We attempted to conduct a case series study of prospectively recruited patients to illustrate the risk of inappropriate cuff inflation without manometry. It was found that the pilot balloon palpation was an inaccurate method to estimate cuff under- or over-inflation, with large discrepancies when compared with an objective measure. Such discrepancies might be independent of doctors' and nurses' working experience in airway management. Use of an aneroid manometer remains an economical and cost-effective way to obtain an instantaneous yet reasonably reliable result and should become a routine in emergency departments.

PURPOSE Supraglottic airway devices (SGAs) can be used as conduits for intubation, but data and manufacturers' recommendations for pediatric SGA are incomplete and sometimes misleading. This situation can result in the use of incompatible combinations of SGAs and endotracheal tubes (ETTs). To address this mismatch possibility, we performed an in vitro study to establish an overview of possible combinations of SGAs and ETTs. METHODS We tested the passage of ETTs through SGAs in vitro and subsequent SGA removal with eight pediatric SGAs and six ETTs of different sizes in vitro. Results were compared with manufacturers' recommendations. Outcome parameters were the feasibility of passing the ETT through the SGA and then removing the SGA over the ETT. RESULTS The Air-Q® and the Air-Q®sp™ SGAs showed the best compatibility with ETTs across all sizes. Whenever intubation was possible, removal was possible for all SGAs with uncuffed ETTs. With many cuffed ETTs, however, SGA removal was impossible because the ETT cuff's pilot balloon was larger than the inner diameter of the SGA. Thus, although intubation was possible, removal of the SGA was not. The manufacturers' booklets do not warn of this limitation. CONCLUSIONS The use of combinations of SGA and ETTs with a size mismatch can lead to airway complications during intubation or to accidental extubation and tearing of the cuff pilot balloon line when removing the SGA. To avoid these problems, we devised a table that simplifies the choice of an appropriate SGA and ETT combination.

Background: Manual inflation of tracheal tube cuff after intubation is necessary to provide a safe airway in intubated patients. An increase or decrease in the pressure of cuff balloon leads to serious complications such as mucosal necrosis and micro aspiration. The aim of the study was to compare the endotracheal tube cuff pressure measurements before and after selected nursing care in emergency patients underwent pilot balloon palpation during cuff inflation. Methods: A prospective cross-sectional design was utilized in the emergency department at Al Manial University Hospital upon a convenient sample of 100 mechanically ventilated patients from April 2016 to June 2017. Demographic and medical data were collected. Later, the endotracheal cuff pressure was checked with manometer before and 15 minutes after each nursing intervention and data were analyzed using SPSS software version 20. Results: The majority of the studied sample was male with mean age 47.09 ± 15. Significant differences were detected regarding Endotracheal suctioning (t=16.99, p=0.000), Changing body position (t=2.76, p=0.026) and sedating patients (t=3.951, P ≤ 0.0001). As changing patients’ body position to lateral sides, performing endotracheal and applying sedation caused a significant decrease in cuff pressure 15 minutes after. Conclusion: ETT cuff pressure was affected significantly with medical and nursing procedures and the pilot balloon palpation volume method was not suitable to estimate cuff pressure during intubation and the cuff pressure must be monitored and controlled by the manometers.

Background With the introduction of redesigned cuffed endotracheal tubes (ETTs), there has been an increasing trend toward their use in pediatric patients. Despite improvements in design, an unintended and prolonged hyperinflation of the cuff can compromise tracheal mucosal perfusion. The current study prospectively monitors changes in intracuff pressure continuously in pediatric patients undergoing prolonged surgical procedures. Methods The study was conducted on pediatric patients who were scheduled to undergo prolonged surgical procedures (more than 4 h) with a cuffed ETT. After placement of the cuffed ETT, the cuff was inflated using the air-leak test with a CPAP of 20 cmH2O in the anesthesia circuit. After inflation, the inflating port of the pilot balloon was connected to the transducer of the invasive pressure monitoring device using our previously described technique to continuously measure the intracuff pressure. Measurements were recorded every 15 min for the first 1 h, and then every 30 min throughout the surgical procedure. Results The study cohort included 30 patients who ranged in age from 1.2 to 17.6 years and in weight from 9.4 to 113.4 kg. There were 16 boys and 14 girls. The size of the cuffed ETT ranged from 3.5 mm to 8.0 mm ID. The baseline intracuff pressure at the time of inflation was 17.6 ± 8.8 cmH2O. The absolute change in the intraoperative intracuff pressure when compared to the baseline intracuff pressure ranged from −25.8 to +16.3 cmH2O. In 9 patients (30%), the decrease of the intracuff pressure was ≥10 cmH2O. In 6 patients (20%), the increase of the intracuff pressure was ≥10 cmH2O. In 5 of 30 patients (17%), the absolute intracuff pressure was greater than 30 cmH2O at least once intraoperatively. In no patient, did the intracuff pressure remain the same as the baseline throughout the procedure. Conclusion We noted significant variations in the intracuff pressure during prolonged surgical procedures. These unintended changes, both increases and decreases, may impact the perioperative course of patients. Our study suggests the need for continuously monitoring intracuff pressure if a cuffed ETT is used in children for prolonged surgical procedures.

Background. Both under- and overinflation of endotracheal tube cuffs can result in significant harm to the patient. The optimal technique for establishing and maintaining safe cuff pressures (20–30 cmH2O) is the cuff pressure manometer, but this is not widely available, especially in resource-limited settings where its use is limited by cost of acquisition and maintenance. Therefore, anesthesia providers commonly rely on subjective methods to estimate safe endotracheal cuff pressure. This study set out to determine the efficacy of the loss of resistance syringe method at estimating endotracheal cuff pressures. Methods. This was a randomized clinical trial. We enrolled adult patients scheduled to undergo general anesthesia for elective surgery at Mulago Hospital, Uganda. Study participants were randomized to have their endotracheal cuff pressures estimated by either loss of resistance syringe or pilot balloon palpation. The pressures measured were recorded. Results. One hundred seventy-eight patients were analyzed. 66.3% (59/89) of patients in the loss of resistance group had cuff pressures in the recommended range compared with 22.5% (20/89) from the pilot balloon palpation method. This was statistically significant. Conclusion. The loss of resistance syringe method was superior to pilot balloon palpation at administering pressures in the recommended range. This method provides a viable option to cuff inflation.

To evaluate the clinical outcomes of alternative techniques of intubation in patients sustaining maxillofacial injuries, where nasotracheal intubation (NTI) is best avoided. Alternative techniques to standard naso-tracheal intubation like submental intubation, orotracheal intubation-retrotuberosity/retromolar and missing dentition were used and variables of clinical outcome recorded. Submental intubation provides an unobstructed intraoral surgical field, avoids intraoperative and postoperative complications of tracheostomy, and overcomes the disadvantages of NTI. In our experience with submental intubation (6 cases), we only had complication related to tube apparatus like damage to pilot balloon. With retrotuberosity intubation (5 cases) we did not encounter any complications and the only limitations were bulbous maxillary tuberosity. Retromolar intubation (4 cases) a safe noninvasive technique has disadvantages like tube interference within the surgical field and not feasible in case of limited retromolar space. Orotracheal-missing dentition intubation (4 cases) is of great advantage i.e. it can be used in cases where NTI is contraindicated, no specialized skill required, no added cost, avoids the need for tracheostomy, no extra-oral procedures required and does not interfere with occlusion/MMF; with disadvantage of occasional tube interference within the surgical field. Preferred techniques of securing an airway like orotracheal, nasotracheal may not always be applicable, thus a trauma surgeon-anesthesist team should always have alternative techniques in their armamentarium to reduce the morbidity associated with these patients without interference with occlusion, which is prime goal in jaw fracture reduction. We have used these techniques in a country with limited resources and found them equally effective and convenient to use.

The consequences of endotracheal tube (ETT) cuff leak may range from a bubbling noise to a life-threatening ventilatory failure. Although the definitive solution is ETT replacement, this is often neither needed nor safe to perform. Frequently, the leak is not caused by a structural defect in the ETT. Cuff underinflation, cephalad migration of the ETT (partial tracheal extubation), misplaced orogastric or nasogastric tubes, wide discrepancy between ETT and tracheal diameters, or increased peak airway pressure can cause leaks around intact cuffs. Correction of these problems will stop the leak without ETT replacement. Alternatively, ETT cuff, pilot balloon, and inflation system damage due to inadvertent trauma or manufacturing defects may be responsible. Conservative management ideas (management without ETT replacement) were previously published to solve the problem. However, when a large structural defect is identified or conservative measures fail, ETT replacement becomes necessary. This can be performed with direct laryngoscopy if laryngeal visualization is adequate. A difficult exchange with possible airway loss should be anticipated, and prepared for, when there are signs and/or history of difficult intubation. A risk/benefit analysis of each individual situation is warranted before decisions are made on how best to proceed. Alternative back-up ventilation plans should be preformulated and the necessary equipment ready before the exchange. In this review, various management concerns and plans are discussed, and a simple algorithm to manage leaky ETT cuff situations is presented.

Solar balloons, in which solar radiation is used to heat directly the air in a hot-air flying balloon, can be used as a mixed power system that exploits both solar radiation and high-altitude winds. If the balloon is heated at ground level and then released, the upward drift due to solar energy and the lateral drift due to wind can both be used to generate energy. At high altitude, the balloon is completely deflated (except for a small Helium-filled chamber, which prevents the balloon from falling) and pulled to the ground: the aerodynamical drag is now strongly reduced with respect to the ascent. A production cycle is simulated for balloons of different sizes and in different working conditions, assessing the feasibility of such a system, calculating the energy output and the solar/wind proportion of the produced energy. Simulation results show that such a system can produce energy with non-negligible solar-to-electricity efficiency (up to 5%). Moreover, while this is primarily a solar-based system, wind can yield a significant amount of additional energy for wind velocities greater than 15. m/s. © 2012 Elsevier Ltd.

BACKGROUND An intact pilot balloon assembly is crucial to the proper function of a cuffed tracheal tube. Disruption of the pilot balloon, transection of the inflation line, or valve incompetence results in cuff deflation, which may lead to inadequate ventilation and aspiration of secretions. Such failures typically result in tracheal tube replacement, but this may be a safety risk if a difficult reintubation is anticipated. We recently encountered such a patient who remained intubated postoperatively and in whom the inflation line was transected, causing a large leak. We describe a method to reconstitute the inflation line and report on the structural integrity of the repair. We hypothesized that the repaired assembly would maintain cuff pressure not statistically different from an intact device, but that the inflation line would be weaker. METHODS The distal (tapered) portion of a 22-gauge intravenous (IV) catheter was partially inserted into the severed end of the inflation line. A new pilot balloon was cut from an intact tracheal tube with the tubing attached, the end of which had been dilated using a 22-gauge IV catheter. The new tubing was then guided over the protruding portion of the catheter, creating an internal stent. We measured the drop in cuff pressure after 8 hours in an artificial trachea for repaired and intact tracheal tubes. We tested the integrity of the repaired segments, underwater, to high-pressure inflation. We measured the static tensile strength of the inflation line from intact and repaired tracheal tubes. Data are presented as the mean ± standard error. Differences were assessed using the unpaired, 2-sided Student t test, with P < .05 required to claim statistical significance. RESULTS Eight-hour interval measurements in 10 intact versus 10 repaired tracheal tubes demonstrated no significant difference in pressure drop (mean difference = 0.5 cm H2O; 95% confidence interval, -2.2 to 1.2 cm H2O; P = .54). There was no visible air leak from 10 repaired inflation line segments when the cuff was inflated to 120 mm Hg. The force needed to break the repaired inflation line was lower than for the intact tubing (n = 7 of each; mean difference = -21.9 N; 95% confidence interval, -25.7 to -18.1 N; P < 10). Repairs to tracheal tubes from various manufacturers with inner diameters ranging from 3.0 to 8.0 mm were successful. CONCLUSIONS Repairing a disrupted pilot balloon assembly using an IV catheter as a stent inside the inflation line is an effective temporizing measure in situations where ventilation is impaired and where tracheal tube replacement may present an excessive patient risk.

The Ambu® Aura40™ reusable laryngeal mask airway (LMA) is a supraglottic airway device that features a built-in curve replicating the natural human anatomy, facilitating correct insertion. In addition, it has a reinforced tip, extra soft cuff, colour-coded pilot balloon and convenient depth marks. Although, the manufacturer’s recommendations state that it can be steam autoclaved up to 40 times for sterilisation prior to reuse, its safety regarding continuing usage is determined by its ability to pass the pre-use test rather than the specific number of times it has been used (1).

If tracheal intubation is not possible using direct laryngoscopy, one option is to use a laryngeal mask airway (LMA) through which an endotracheal tube (ETT) can be passed. In children, however, the size of an uncuffed ETT that can pass through the lumen of an LMA is sometimes too small for the trachea, resulting in gas leakage around the ETT. Using a cuffed ETT may reduce the gas leak but withdrawal of the LMA is then prevented by the pilot balloon. In this study, the largest sizes of cuffed and uncuffed Mallinckrodt™ ETTs that could pass with ease through various sizes of paediatric Classic™ and ProSeal™ LMAs were documented. For cuffed ETTs, withdrawal of the LMA was made possible by simply cutting off the pilot balloon. The ETT cuff-inflating mechanism was then repaired by passing a 20 or 22 gauge cannula into the cut end of the inflating tubing. The proximal end of the cannula was then connected to a one-way valve or a three-way stopcock. This technique of cutting off the pilot balloon of the cuffed ETT made it possible to use paediatric cuffed ETTs in exchange for the LMAs tested. The task was easy to perform. Subsequent repair of the cuff-inflation tubing was effective and could withstand high pressures. These findings indicate that it is possible to pass cuffed ETTs through paediatric LMA lumens, which can provide ventilation without gas leaks, unlike uncuffed ETTs.

We studied the effect of pilot balloon design on the ability of experienced anaesthetists to assess and inflate tracheal tube cuffs to safe pressures. A model trachea was designed, incorporating a degree of compliance and an air leak, to evaluate six different pilot balloons grafted onto identical tracheal tubes. Pilot balloons were inflated to one of four pressures and anaesthetists were asked to estimate whether the pressure was acceptable, too low or too high. Anaesthetists were then asked to inflate the cuff of each tube. Overall, 103 (42.9%) of anaesthetists' assessments of tracheal tube cuff pressures were correct (33% correct would be expected by chance, p = 0.002). Pressures generated by anaesthetists inflating tracheal tube cuffs were very variable. Median (IQR [range]) pressures for each pilot balloon ranged from 29 (17-43 [9-56]) cmH(2)O to 74 (49-114 [4-140]) cmH(2)O (p < 0.001). The design of the pilot balloon significantly affects anaesthetists' ability to inflate tracheal tube cuffs to safe pressures.

When a pilot balloon fails or is an impediment to an intubation, such as via a pediatric laryngeal mask, options are generally limited to a tracheal tube exchange. Simple and effective solutions are described to replace a pilot balloon in a variety of clinical situations by using equipment that is readily available in operating rooms. Equipment such as intravenous catheters or epidural clamp connectors provides reliable, light weight, and streamlined substitutions for pilot balloons when connected to the pilot-cuff inflation line.

Background: High cuff pressure of tracheal tube (TT) may cause tracheal damage. Maintaining an optimal cuff pressure is important in tracheal intubation. This study aimed to examine whether inexperienced anesthetists or airway care providers, after training and practice, demonstrate more expertise in the determination of optimal cuff pressure by feeling the pilot balloon with their fingers. Methods: One hundred participants were asked to inflate the TT cuff with an air volume that they believe to be correct based on their previous experience. The cuff pressure after inflation was measured by a manometer. Then, the cuff of a standard adult TT was inflated with air until the pressure reached 25 cm H2O, and each participant was instructed to palpate the pilot balloon to feel the pressure, until s/he became accustomed to the feeling. After training, the same procedure was performed immediately, and repeated 1 week and 1 month later. We compared the pre-training data with the post-training data, and the differences between seniority of employment and age. Results: A total of 98 examinees completed the study. Before training, the mean cuff pressure they determined to be correct was actually 29.3±19.49 cmH2O; 32.7% of the examinees had over-inflated the cuff. The cuff pressures they inflated immediately, 1 week and 1 month after training were significantly different from those found before training (p=0.009, p=0.038 and p=0.045, respectively). Before training, the performance of the participants who were of middle seniority (5-10 years of experience) and middle age (30-45 years old) was significantly better than that of the less experienced (＜ 5 years of experience; p =0.007) and younger participants (＜30 years old; p=0.002). Conclusion: The anesthesia trainers in this study are capable of teaching TT cuff inflation correctly. After practical training, the airway care providers, irrespective of seniority or age, can roughly determine an optimal TT cuff pressure non-instrumentally.