Pharyngeal Pressure Research Articles

Effect of Lidocaine on Comfort and Swallowing Pressures During Pharyngeal High-Resolution Manometry.

The purpose of this study is to determine the level of patient comfort during pharyngeal high-resolution manometry (HRM) with and without the use of atomized lidocaine. A secondary aim of the study was to explore whether differences in pharyngeal pressure measurements exist between HRM conducted with the use of atomized lidocaine verses HRM conducted without. Twenty-nine participants underwent two HRM procedures under two conditions, 5-7days apart: 2% viscous lidocaine to nares or 0.4mL 4% atomized and 2% viscous lidocaine to nares. During each procedure, participants received six boluses of water. Following catheter removal, participants were asked to rate comfort using a visual analog scale (VAS) and upon completion of both conditions, participants indicated which procedure they preferred. A paired t-test was used to compare pharyngeal pressure measurements at the velopharynx, tongue base region and during upper esophageal sphincter opening. Pharyngeal pressures were categorized as normal or outside of normal limits and compared using a McNemar's test. Twenty-eight of the 29 participants indicated they preferred the use of atomized lidocaine. VAS ratings yielded a significant difference (p = 0.001). No significant difference in pharyngeal pressures were detected between the two groups. Patients prefer atomized lidocaine when undergoing HRM. The use of atomized lidocaine did not affect measurement outcomes.

Pharyngeal Swallowing Pressures in Patients with Radiation-Associated Dysphagia.

Dysphagia associated with radiotherapy for head and neck cancer is complex and can be difficult to treat. Videofluoroscopic swallow studies (VFSS) are the current gold-standard instrumented swallow assessment. High-resolution manometry (HRM) is an additional approach that provides objective measurements of swallowing-related pressures in the pharynx and esophagus. This can provide functional information on the pressure gradients underlying bolus propulsion, and is relevant for this patient population, where radiation-related fibrosis can lead to weakness and impaired pressure generation. The purpose of this preliminary study was to describe pharyngeal swallowing pressures in patients with radiation-associated dysphagia (RAD) and late radiation-associated dysphagia (LRAD) using HRM. RAD occurs during and immediately following treatment, whereas LRAD is a more recently described phenomenon in which the patient experiences an onset of dysphagia at least 5years post-treatment. We performed a retrospective analysis of pharyngeal swallowing pressures from 21 patients with RAD or LRAD and 21 healthy sex/age-matched controls. Patients with RAD or LRAD exhibited decreased swallowing pressure durations throughout the pharynx (p ≤ 0.002), as well as decreased hypopharynx maximum pressure (p = 0.003) and pharyngeal contractile integral ( p < 0.0001). Understanding how pharyngeal pressure generation is altered in patients with a history of radiotherapy can help clinicians form more precise treatment plans.

Adequate Number of Swallows for Pharyngeal Pressure Measurement of a Subject using High-resolution Manometry.

Introduction The number of pressure measurements that need to be recorded using high-resolution manometry (HRM) for the accurate evaluation of pharyngeal function is not well established. Objective The purpose of this study is to clarify the number of swallows required to obtain an accurate pharyngeal manometric profile of a person. Methods Forty healthy adults performed a dry swallow and bolus swallows using 3-, 5-, or 10 ml of water and underwent measurements using the Starlet HRM system. Each subject underwent 10 swallows for each of the four bolus volume conditions. Results The mean of up to seven measurements of maximum pre-swallow upper esophageal sphincter pressure with 10 ml of swallow was close to the mean of up to eight measurements in 95% of the subjects. Similarly, the rate of change of the average for the eighth and ninth measurements and the rate of change for the average of the ninth and tenth measurements were less than 5%. When the other parameters were similarly measured up to the sixth measurement, no major change in the average value was observed even if more measurements were taken. Conclusion A minimum of six measurements are required, and seven swallows are sufficient for evaluating the pharyngeal manometric profile of a single person. This number of measurements can be a useful criterion when performing HRM measurements on individual subjects.

Swallowing Pressure Variability as a Function of Pharyngeal Region, Bolus Volume, Age, and Sex

Within-individual movement variability occurs in most motor domains. However, it is unknown how pharyngeal swallowing pressure varies in healthy individuals. We hypothesized that: 1) variability would differ among pharyngeal regions; 2) variability would decrease with increased bolus volume; 3) variability would increase with age; and 4) there would be no sex differences. Case series. We used pharyngeal high-resolution manometry to measure swallowing pressure in the following regions: velopharynx, tongue base, hypopharynx, and upper esophageal sphincter. Data were collected from 97 healthy adults (41 male) aged 21 to 89 years during thin liquid swallows: 2 mL, 10 mL, and participant-selected comfortable volume. Pressure variability was measured using coefficient of variation. Repeated measures analysis of variance was used to assess impacts of region, bolus volume, age, and sex on pressure variability. There was a significant region × volume interaction (P < .001) and significant main effect of age (P = .005). Pressures in the hypopharynx region were more variable than all other regions (P ≤ .028), and pressures in the tongue base region were less variable than all other regions (P ≤ .002) except at 2 mL volumes (P = .065). Swallowing pressure variability was significantly different in the velopharynx and upper esophageal sphincter regions, with comfortable volume and 2 mL swallows having greater variability than 10 mL swallows (P ≤ .026). Pressure variability significantly increased with increasing age (P = .002). There were no effects of sex on pressure variability (P ≥ .15). Pharyngeal swallowing pressure variability differs according pharyngeal region, volume, and age but not sex. Abnormal swallowing pressure variability may reflect deviations in motor control in persons with swallowing impairment, and results from this study can be used as normative data for future investigations evaluating swallowing pressure generation. 4 Laryngoscope, 131:E52-E58, 2021.

The value of the pharyngeal airway pressure monitoring test in topodiagnosis of OSA

Objective:To analyses the value of an improved methods of Muller's test, pharyngeal airway pressure monitoring test（PAPMT）, in topodiagnosis of OSA. Method:One hundred and one cases with OSA（AHI≥5 times per hour） and 30 normal adults were included in the study. Under the pressure monitoring, the electronic laryngoscope were stayed at the palatopharyngeal and glossopharyngeum. First, observe the maximum expiratory pressure and the minimum spiratory pressure. And then measure and record changes of pharynx cross-sectional area at palatopharyngeal and glossopharyngeum under the different pressure. At Last, analyses the correlation between changes of Pharynx cross-sectional area with polysomnography（PSG）. Result:①In 101 cases with OSA, the maximal inspiratory pressure of Müller's manerver distribution is between 1 and 8 kPa. ②The changes of pharynx cross-sectional area of OSA at palatopharyngeal and glossopharyngeum is significantly greater than the control group, and there were obvious differences between OSA and the control group. ③In OSA group, the plug rate at palatopharyngea was 96% and the plug rate at glossopharyngeum is 34% at the minimum pressure. There are no cases have pharynx jams at the control group. ④The main cause of the palatopharyngeal obstruction was strictures in left and right（73%）, and the anatomical factors causing obstruction mainly were, thicken of the pharyngeal wall. The main cause of the hypopharyngeal obstruction was strictures in front and back（71%）, and the redundant lymph tissue at tongue base and posterior displacement of the tongue base, and collapse of pharyngeal wall played an important role at tongue-pharyngeal obstruction. ⑤The changes of pharynx cross-sectional area at palatopharyngeal and glossopharyngeum when the pressure is ±4 kPa is greater than when the pressure is ±2 kPa. ⑥When the pressure is ±2 kPa, The changes of pharynx cross-sectional area at palatopharyngeal is greater than at glossopharyngeum. ⑦Diminished pharyngeal apertures and collapsibility were associated with increased rates of apnea and hypopnea index and the suction pressure（P<0.05）. Conclusion:①PAPMT is able to measure and calculate the changes of pharynx cross-sectional area, determine the site of obstruction, and help the treatment. ②The primary site of obstruction is at velopharyngeal in OSA group. ③The changes of pharynx cross-sectional area at palatopharyngeal and glossopharyngeum of patients can reflects the severity of the OSA.

Comparison of delivered distending pressures in the oropharynx in preterm infant on bubble CPAP and on three different nasal interfaces.

To compare the level of continuous positive airway pressure (CPAP) delivered by three different CPAP delivery interfaces (RAM cannula system, Hudson prongs, and nasal mask) in preterm neonates with respiratory distress. Preterm neonates with gestation between 28 weeks and 34 weeks and birth weight more than or equal to 1000 g and requiring nasal CPAP for respiratory distress were eligible for the study. During the study period, consecutive infants requiring CPAP were started on Hudson prongs or RAM cannula or nasal mask in that order. We measured the mean oropharyngeal pressure, which approximates the applied CPAP level. Oropharyngeal pressures in the recruited neonates were measured between 24 and 48 hours of postnatal age, when stable and in sleep or quiet awake state. Comparison of the delivered oropharyngeal pressures when on three different nasal interfaces at the same set flow rate and at set CPAP of 5 cm or 6 cm of H2 O was the primary outcome. Data was analyzed from 30 neonates in each group. We found that measured oropharyngeal pressures were less than set CPAP level in all three studied interfaces. Maximum drop in oropharyngeal pressure was observed with use of RAM cannula with measured oropharyngeal pressures being 1.1 and 1.2 cm H2 O less than set CPAP of 5 and 6 cm H2 O respectively. Pharyngeal pressure best correlated to set CPAP level with the use of nasal mask. None of the nasal interfaces delivered oropharyngeal pressure equivalent to the set CPAP. However, nasal mask delivered oropharyngeal pressure best matched to the set CPAP.

Morphine alters respiratory control but not other key obstructive sleep apnoea phenotypes: a randomised trial.

Accidental opioid-related deaths are increasing. These often occur during sleep. Opioids such as morphine may worsen obstructive sleep apnoea (OSA). Thus, people with OSA may be at greater risk of harm from morphine. Possible mechanisms include respiratory depression and reductions in drive to the pharyngeal muscles to increase upper airway collapsibility. However, the effects of morphine on the four key phenotypic causes of OSA (upper airway collapsibility (pharyngeal critical closure pressure; P crit), pharyngeal muscle responsiveness, respiratory arousal threshold and ventilatory control (loop gain) during sleep) are unknown.21 males with OSA (apnoea-hypopnoea index range 7-67 events·h-1) were studied on two nights (1-week washout) according to a double-blind, randomised, cross-over design (ACTRN12613000858796). Participants received 40 mg of MS-Contin on one visit and placebo on the other. Brief reductions in continuous positive airway pressure (CPAP) from the therapeutic level were delivered to induce airflow limitation during non-rapid eye movement (REM) sleep to quantify the four phenotypic traits. Carbon dioxide was delivered via nasal mask on therapeutic CPAP to quantify hypercapnic ventilatory responses during non-REM sleep.Compared to placebo, 40 mg of morphine did not change P crit (-0.1±2.4 versus -0.4±2.2 cmH2O, p=0.58), genioglossus muscle responsiveness (-2.2 (-0.87 to -5.4) versus -1.2 (-0.3 to -3.5) μV·cmH2O-1, p=0.22) or arousal threshold (-16.7±6.8 versus -15.4±6.0 cmH2O, p=0.41), but did reduce loop gain (-10.1±2.6 versus -4.4±2.1, p=0.04) and hypercapnic ventilatory responses (7.3±1.2 versus 6.1±1.5 L·min-1, p=0.006).Concordant with recent clinical findings, 40 mg of MS-Contin does not systematically impair airway collapsibility, pharyngeal muscle responsiveness or the arousal threshold in moderately severe OSA patients. However, consistent with blunted chemosensitivity, ventilatory control is altered.

Long-term obstructive sleep apnea therapy: a 10-year follow-up of mandibular advancement device and continuous positive airway pressure

Obstructive sleep apnea (OSA) is a sleep-related breathing disorder, commonly managed by either continuous positive airway pressure (CPAP) or a mandibular advancement device (MAD). Long-term follow-up and comparison regarding efficacy of these therapies is scarce. In this study the results of treatment, patient adherence, and satisfaction over a 10-year follow-up of these therapies are reported. This is a longitudinal follow-up study taken from a subset of patients initially enrolled in a randomized controlled clinical trial of 103 patients with OSA (51 and 52 patients randomized for MAD and CPAP, respectively). After a 10-year follow-up period, 14 patients using MAD and 17 patients using CPAP could be evaluated for this longitudinal follow-up study. Data were analyzed at baseline, after 3 months and at 1-, 2-, and 10-year follow-up. All 31 patients with OSA underwent polysomnography and self-reported measurements. Polysomnography results showed a favorable outcome of both therapies at 10-year follow-up. At baseline, included patients in both groups did not significantly differ in apnea-hypopnea index (AHI) values. At 10-year follow-up, both the MAD and CPAP groups showed a significant reduction in AHI. At baseline the mean AHI in the MAD group was 31.7 ± 20.6 events/h whereas in the CPAP group it was 49.2 ± 26.1 events/h. At 10-year follow-up the mean AHI in the MAD group was 9.9 ± 10.3 events/h and in the CPAP group it was 3.4 ± 5.4 events/h. Both therapies resulted in a substantial improvement in self-reported neurobehavioral outcomes at 10-year follow-up. Both CPAP and MAD therapy demonstrate good and stable treatment effects after a 10-year follow-up period. Therefore, when indicated, both therapies are appropriate modalities for the long-term management of OSA. Registry: Netherlands Trial Register; Name: Management of the Obstructive Sleep Apnea-Hypopnea Syndrome: Oral Appliance versus Continuous Positive Airway Pressure Therapy; Identifier: NL75; URL: https://www.trialregister.nl/trial/75.

Twenty years of quantitative instrumental measures of swallowing in children: a systematic review.

Early identification and intervention has shown better health outcomes for children with dysphagia. Instrumental swallowing assessments are vital and have been a focus of dysphagia research in the last two decades. This systematic review explores published quantitative instrumental measures of swallowing in children. Five subject-related databases were searched to identify original scientific articles published in English, using instrumental quantitative measures of swallowing to study swallowing/feeding mechanism in children since 1998. Two thousand two hundred and two articles were found from the initial database search and 36 were included in the final qualitative synthesis following PRISMA guidelines. Selected studies showed great diversity in target population, phase/s of swallowing studied, instrumentation used (n = 10) and quantitative measures reported (n = 144). Videofluoroscopy and manometry have been studied most repeatedly. With less frequency, a variety of other instruments has been used to describe suck-swallow patterns and swallowing-related respiration. High-resolution manometry shows the greatest increase in publications with validated, reliable quantitative measures of pharyngeal and oesophageal pressures and timing. More recently, quantification of videofluoroscopy analysis has been a focus.Conclusion: A diverse range of quantitative measures of swallowing is available for children in the literature. However, further reliability and validity testing is needed. Opportunities for clinical application of these quantitative manometric and videofluoroscopic measures are restricted by limited normative comparisons and vast variability in published measures.What is known?• Instrumental swallowing assessments are reliable and accurate in diagnosing swallowing difficulties in children.• However, subjective interpretation of observational findings often questions the optimal use of instrumentation.What is new?• High-resolution manometry has shown promising progress with the development of quantitative objective swallow measures for children. While attempts to quantify video-fluoroscopic measures have been increased in the recent past.• A vast variety of instruments has been used to obtain quantitative and/or objective swallow measures of children, yet clinical application is still in progress.

How does distraction osteogenesis maxillary expansion (DOME) reduce severity of obstructive sleep apnea?

Distraction osteogenesis maxillary expansion (DOME) is a reliable method to expand the nasal floor and hard palatal vault in adults with obstructive sleep apnea (OSA). DOME results in a reduction in the apnea-hypopnea index (AHI) and subjective report of improved nasal breathing. Using rhinomanometry augmented computational fluid dynamic (CFD) modeling, we propose a mechanism of how DOME reduces upper airway pharyngeal collapse in adults with OSA. A retrospective cohort with 20 subjects and mean age of 29.6 ± 8 years who completed DOME at Stanford University from September 2014 to April 2016. Subjects were included if polysomnography, airway morphology, and rhinomanometry were available for use. From the CBCT data, 3D nasal and pharyngeal airway model were generated. Numeric CFD simulation of the airway models were analyzed under the following conditions: (1) the volume of air was flowing at a velocity of 300 cm3/s, (2) the wall surface was not slippery, and (3) the simulations were repeated 1000 times to calculate mean values. Statistical analyses using SPSS v24 software included paired t tests, nonparametric Wilcoxon rank test, Friedman test with Bonferroni correction, and Spearman's correlation coefficients (p < 0.05). Mean AHI improved from 17.8 ± 17.6 to 7.8 ± 7.1 events per hour (p < 0.001). Mean lowest oxygen saturation improved from 88.2 ± 7.2 to 90.9 ± 4.2% (p < 0.05). Mean airflow velocity within the nasal airway decreased from 15.6 ± 7.3 to 7.4 ± 2.1 m/s (p < 0.001) after DOME. Mean negative pressure of the nasal airway, retropalatal airway, oropharyngeal airway, and hypopharyngeal airway is reduced from - 158.4 ± 115.3 to - 48.6 ± 28.7 Pa, from - 174.8 ± 119.9 to - 52.5 ± 31.3 Pa, from - 177.0 ± 118.4 to - 54.9 ± 31.8 Pa and from - 177.9 ± 117.9 to - 56.9 ± 32.1 Pa (p < 0.001), respectively. AHI positively correlated with nasal flow velocity (p < 0.05) and negatively correlated with pharyngeal airway pressure (p < 0.05). ODI was positively correlated with nasal velocity (p < 0.05) and negatively correlated with nasal airway pressure (p < 0.05), retropalatal airway pressure (p < 0.001), oropharyngeal airway pressure (p < 0.001), and hypopharyngeal airway pressure (p < 0.05). Anatomic expansion of the nasal floor with widening of the hard palatal vault from DOME is associated with reduction of nasal airflow velocity and downstream reduction of negative pressure in the pharyngeal airway. This dynamic interaction correlates with a reduction in the apnea-hypopnea index (AHI) and Oxygen Desaturation Index (ODI).

Pharyngeal swallowing mechanics associated with upper esophageal sphincter pressure wave.

Opening of the upper esophageal sphincter (UES) is a critical element of swallowing. Understanding the functional pharyngeal anatomy during UES opening would be clinically useful for dysphagia evaluation and treatment. Simultaneous high-resolution pharyngeal manometry and videofluoroscopy (VFS) videos for 18 nondysphagic subjects were evaluated. UES pressure readings were segmented into six pressure phases, including a poorly understood pre-relaxation contraction. Anatomic landmarks were tracked in VFS imaging and evaluated morphometrically to determine the movement of key swallowing structures within each UES pressure phase. There were significant differences in pharyngeal mechanics by UES pressure stage (range of D-values = 1.7-2.2, P < .0001). The soft palate maximally elevates during the pre-relaxation contraction of the UES. Early during UES relaxation, the hyolaryngeal complex and pharyngeal structures maximally elevate and pharyngeal structures constrict around the bolus. The mechanics underlying the UES pressure wave suggest generation of a sealed pharyngeal cavity, possibly integral to pharyngeal pressure generation and bolus propulsion.

AGE-RELATED FUNCTIONAL RESERVE DECLINE IS NOT SEEN IN PHARYNGEAL SWALLOWING PRESSURES

Age-related decline in functional reserve has been described in tongue strength: tongue pressure during swallowing does not change with age, but maximal-effort isometric tongue pressure decreases with age. Healthy persons show a slight increase in pharyngeal swallowing pressure with age, but it is unknown if there is a similar decline in functional reserve. Fifty-six healthy adults (n=38 60 years) underwent pharyngeal high-resolution manometry during effortful and normal-effort thin liquid swallows. Repeated measures ANOVAs were performed on maximum pressures, pharyngeal contractile integral (PCI), pharyngeal pressure gradients, and upper esophageal sphincter minimum pressures. We hypothesized that older individuals would generate a less-robust pressure increase with effortful swallowing than younger individuals. Maximum pressures, PCI, and gradients increase during effortful swallowing (p<0.001), but there was no interaction effect with age, suggesting a lack of age-related functional reserve decline. Older individuals had greater UES minimum pressures than younger individuals in the effortful swallowing task (p=0.03), which may stem from reduced muscular compliance in this area. These findings do not align with those reported in tongue pressures, suggesting that muscle properties and pressure generation may be fundamentally different between the pharynx and the oral tongue. Alternatively, the effortful swallowing task may not elicit maximum contractility of the pharyngeal musculature. The preserved ability to increase pharyngeal pressure during effortful swallowing may support the use of the effortful swallow exercise in older adults with swallowing disorders.

Upper Airway Collapsibility during Dexmedetomidine and Propofol Sedation in Healthy Volunteers: A Nonblinded Randomized Crossover Study.

Dexmedetomidine is a sedative promoted as having minimal impact on ventilatory drive or upper airway muscle activity. However, a trial recently demonstrated impaired ventilatory drive and induction of apneas in sedated volunteers. The present study measured upper airway collapsibility during dexmedetomidine sedation and related it to propofol. Twelve volunteers (seven female) entered this nonblinded, randomized crossover study. Upper airway collapsibility (pharyngeal critical pressure) was measured during low and moderate infusion rates of propofol or dexmedetomidine. A bolus dose was followed by low (0.5 μg · kg · h or 42 μg · kg · min) and moderate (1.5 μg · kg · h or 83 μg · kg · min) rates of infusion of dexmedetomidine and propofol, respectively. Complete data sets were obtained from nine volunteers (median age [range], 46 [23 to 66] yr; body mass index, 25.4 [20.3 to 32.4] kg/m). The Bispectral Index score at time of pharyngeal critical pressure measurements was 74 ± 10 and 65 ± 13 (mean difference, 9; 95% CI, 3 to 16; P = 0.011) during low infusion rates versus 57 ± 16 and 39 ± 12 (mean difference, 18; 95% CI, 8 to 28; P = 0.003) during moderate infusion rates of dexmedetomidine and propofol, respectively. A difference in pharyngeal critical pressure during sedation with dexmedetomidine or propofol could not be shown at either the low or moderate infusion rate. Median (interquartile range) pharyngeal critical pressure was -2.0 (less than -15 to 2.3) and 0.9 (less than -15 to 1.5) cm H2O (mean difference, 0.9; 95% CI, -4.7 to 3.1) during low infusion rates (P = 0. 595) versus 0.3 (-9.2 to 1.4) and -0.6 (-7.7 to 1.3) cm H2O (mean difference, 0.0; 95% CI, -2.1 to 2.1; P = 0.980) during moderate infusion of dexmedetomidine and propofol, respectively. A strong linear relationship between pharyngeal critical pressure during dexmedetomidine and propofol sedation was evident at low (r = 0.82; P = 0.007) and moderate (r = 0.90; P < 0.001) infusion rates. These observations suggest that dexmedetomidine sedation does not inherently protect against upper airway obstruction.

Deglutition in Patients With Hypernasality Associated With Unilateral Cleft Lip and Palate Evaluated With High-Resolution Manometry.

To evaluate pharyngeal pressure profiles during swallowing in patients with unilateral cleft lip and palate (UCLP) and identify compensation mechanisms. Prospective experimental study. University Hospital and Medical School. Ten volunteers and 10 patients with nonsyndromic repaired UCLP with hypernasality (age: 19-27 years, 5 females and 5 males per group) were included. All participants swallowed 2 and 10 mL of water and underwent high-resolution manometry (HRM). Pharyngeal and upper esophageal sphincter (UES) parameters were measured using HRM. Student t test was used for statistical intergroup comparisons. Additionally, the Sydney Swallowing Questionnaire (SSQ) was used as a subjective measure. Patients exhibited reduced velopharyngeal closing pressure and velopharyngeal and tongue base (TB) region contraction times, compared to volunteers (P < .05). The UES opening and closing functions did not change. The SSQ revealed nasal regurgitation in some patients. In patients with UCLP, velopharyngeal region alterations are caused by impaired muscle force and function. The reduced TB contraction time may be a compensation mechanism allowing bolus transportation without nasal regurgitation. However, deglutition is not completely altered since UES function remains normal. Future studies will need to reveal at which point a decrease in velopharyngeal closing pressure will result in velopharyngeal insufficiency.

Genioglossus reflex responses to brief pulses of negative pharyngeal pressure in people with multiple sclerosis

Genioglossus reflex responses to brief pulses of negative pharyngeal pressure in people with multiple sclerosis

A computational fluid dynamics simulation of liquid swallowing by impaired pharyngeal motion: bolus pathway and pharyngeal residue.

Common practices to improve the ability to swallow include modifying physical properties of foods and changing the posture of patients. Here, we quantified the effects of the viscosity of a liquid bolus and patient posture on the bolus pathway and pharyngeal residue using a computational fluid dynamics simulation. We developed a computational model of an impaired pharyngeal motion with a low pharyngeal pressure and no pharyngeal adaptation. We varied viscosities from 0.002 to 1 Pa·s and postures from -15° to 30° (from nearly vertical to forward leaning). In the absence of pharyngeal adaptation, a honey-like liquid bolus caused pharyngeal residue, particularly in the case of forward-leaning postures. Although the bolus speed was different among viscosities, the final pathway was only slightly different. The shape, location, and tilting of the epiglottis effectively invited a bolus to two lateral pathways, suggesting a high robustness of the swallowing process.NEW & NOTEWORTHY Thickening agents are often used for patients with dysphagia. An increase in bolus viscosity not only reduces the risk of aspiration but also can cause a residual volume in the pharynx. Because information obtained from videofluoroscopic swallowing studies is only two-dimensional, measurement of pharyngeal residue is experimentally difficult. We successfully quantified the three-dimensional bolus pathway and the pharyngeal residual volume using computational modeling and simulation.

Lateral pharyngeal flap with a double pedicle for repair of unilateral velopharyngeal insufficiency

ObjectivesConventional pharyngeal flap surgery, which closes the median portion of the velopharynx, has been performed for dysarthria patients with velopharyngeal insufficiency (VPI). However, for VPI due to unilateral pharyngeal paralysis, median closing disrupts pharyngeal contraction of the unaffected side and allows pharyngeal pressure to escape through the nose at the lateral portion of the affected side during speech and swallowing. The purpose of this study was to evaluate the effectiveness of lateral pharyngeal flap (LPF) surgery for unilateral VPI. MethodsSeven patients with unilateral VPI (five males and two females with an average age of 54 years) underwent LPF surgery combined with other transoral surgeries for dysphagia. The LPF surgical technique was as follows: after the laterocaudal-based pedicle flap of the soft palate and cranial-based pedicle flap of the posterior pharyngeal wall on the affected side were transorally elevated, each mucosal pedicle flap was sutured together. Functional oral intake scale (FOIS) scores and swallowing pressure before and after surgery were compared. ResultsUnilateral velopharyngeal closure preserved nasal breathing after LPF surgery in all patients. Rhinolalia aperta improved postoperatively in all patients except one. The mean FOIS scores were 2.3 preoperatively and 3.7, 5.3, and 5.9 at 2 weeks, 1 month, and 6 months postoperatively, respectively. The mean pressures significantly increased at the velopharynx (from 49±30mmHg to 92±45mmHg) and oropharynx (from 48±18mmHg to 66±15mmHg) six months after the surgery. ConclusionLPF surgery leaving the unaffected side intact can be an effective surgical procedure for patients with unilateral VPI.

Transmission of Oral Pressure Compromises Oronasal CPAP Efficacy in the Treatment of OSA

An oronasal mask is frequently used to treat OSA. In contrast to nasal CPAP, the effectiveness of oronasal CPAP varies by unknown mechanisms. We hypothesized that oral breathing and pressure transmission through the mouth compromises oronasal CPAP efficacy. Thirteen patients with OSA, well adapted to oronasal CPAP, were monitored by full polysomnography, pharyngeal pressure catheter, and nasoendoscope. Patients slept with low doses of midazolam, using an oronasal mask with sealed nasal and oral compartments. CPAP was titrated during administration by the oronasal and nasal routes, and was then reduced to induce stable flow limitation and abruptly switched to the alternate route. In addition, tape sealing the mouth was used to block pressure transmission to the oral cavity. Best titrated CPAP was significantly higher by the oronasal route rather than the nasal route (P= .005), and patients with > 25%oral breathing (n= 5) failed to achieve stable breathing during oronasal CPAP. During stable flow limitation, inspiratory peak flow was lower, driving pressure was higher, upper airway inspiratory resistance was higher, and retropalatal and retroglossal area were smaller by the oronasal rather than nasal route (P< .05 for all comparisons). Differences were observed even among patients with no oral flow and were abolished when tape sealing the mouth was used (n= 6). Oral breathing and transmission of positive pressure through the mouth compromise oronasal CPAP.

The effect of a chin-down maneuver after esophagectomy on oropharyngeal swallowing pressure measured using high-resolution manometry

ObjectiveTo elucidate the effects of a chin-down maneuver using high-resolution manometry (HRM) to measure pharyngeal swallowing pressure (SP) after esophagectomy. MethodsWe evaluated 9 of 16 patients who underwent esophagectomy featuring gastric tube reconstruction and three-field lymph node dissection (3FL) in our Department of Gastroenterological Surgery from September 2015 to June 2016. We compared all parameters of the neutral and chin-down positions using HRM to measure the maximum SP at the velopharynx, meso-hypopharynx, and upper esophageal sphincter (UES) and the duration of lowered SP at the UES, the distance from nostrils to the boundary between hypopharynx and UES and to derive SP and SP propagation curves at various distances from the nostrils. ResultsCompared to that at the neutral position, the maximum SP at the velopharynx was significantly lower in the chin-down position (p<0.05); however, SP at the meso-hypopharynx and UES did not differ significantly. The duration of lowered SP at the UES was significantly prolonged in the chin-down position and the distance from nostrils to the boundary between hypopharynx and UES was significantly shortened representing the elevation of the larynx, respectively (p<0.05, p<0.01). On the SP propagation curve for males, the times to SP peaks at 13, 16, 17, and 18cm from the nostrils were significantly prolonged (all p<0.05) in the chin-down position. ConclusionChin-down positioning after esophagectomy/3FL may improve bolus passage by prolonging the duration of lowered SP at the UES, possibly by enhancing laryngeal elevation.

High-Resolution Pharyngeal Manometry and Impedance: Protocols and Metrics-Recommendations of a High-Resolution Pharyngeal Manometry International Working Group.

High-resolution manometry has traditionally been utilized in gastroenterology diagnostic clinical and research applications. Recently, it is also finding new and important applications in speech pathology and laryngology practices. A High-Resolution Pharyngeal Manometry International Working Group was formed as a grass roots effort to establish a consensus on methodology, protocol, and outcome metrics for high-resolution pharyngeal manometry (HRPM) with consideration of impedance as an adjunct modality. The Working Group undertook three tasks (1) survey what experts were currently doing in their clinical and/or research practice; (2) perform a review of the literature underpinning the value of particular HRPM metrics for understanding swallowing physiology and pathophysiology; and (3) establish a core outcomes set of HRPM metrics via a Delphi consensus process. Expert survey results were used to create a recommended HRPM protocol addressing system configuration, catheter insertion, and bolus administration. Ninety two articles were included in the final literature review resulting in categorization of 22 HRPM-impedance metrics into three classes: pharyngeal lumen occlusive pressures, hypopharyngeal intrabolus pressures, and upper esophageal sphincter (UES) function. A stable Delphi consensus was achieved for 8 HRPM-Impedance metrics: pharyngeal contractile integral (CI), velopharyngeal CI, hypopharyngeal CI, hypopharyngeal pressure at nadir impedance, UES integrated relaxation pressure, relaxation time, and maximum admittance. While some important unanswered questions remain, our work represents the first step in standardization of high-resolution pharyngeal manometry acquisition, measurement, and reporting. This could potentially inform future proposals for an HRPM-based classification system specifically for pharyngeal swallowing disorders.