Elevated Average Maximum Intrabolus Pressure on High-Resolution Manometry is Associated with Esophageal Dysmotility and Delayed Esophageal Emptying on Timed Barium Esophagram

Background Intrabolus pressure (IBP) recorded by high-resolution manometry (HRM) portrays the compartmentalized force on a bolus during esophageal peristalsis. HRM may be a reliable screening tool for esophageal dysmotility in patients with elevated average maximum IBP (AM-IBP). Timed barium esophagram (TBE) is a validated measure of esophageal emptying disorders, such as esophagogastric junction outflow obstruction and achalasia. This study aimed to determine if an elevated AM-IBP correlates with esophageal dysmotility on HRM and/or delayed esophageal emptying on TBE. Methods A retrospective analysis of all HRM (unweighted sample n=155) performed at a tertiary referral center from 09/2015-03/2017 yielded a case group (n=114) with abnormal AM-IBP and a control group (n=41) with a normal AM-IBP (pressure<17mmHg) as consistent with Chicago Classification 3. All patients received a standardized TBE, with abnormalities classified as greater than 1 cm of retained residual liquid barium in the esophagus at 1 and 5 minutes or as tablet retention after 5 minutes. Results AM-IBP was significantly related to liquid barium retention (p=0.003) and tablet arrest on timed barium esophagram (p=0.011). A logistic regression model correctly predicted tablet arrest in 63% of cases. Tablet arrest on AM-IBP correlated with an optimal prediction point at 20.1 mmHg on HRM. Patients with elevated AM-IBP were more likely to have underlying esophageal dysmotility (95.6% vs. 70.7% respectively; p<0.001), particularly esophagogastric junction outflow obstruction disorders. Elevated AM-IBP was associated with incomplete liquid bolus transit on impedance analysis (p=0.002). Conclusions Our findings demonstrate that an elevated AM-IBP is associated with abnormal TBE findings of esophageal tablet retention and/or bolus stasis. An abnormal AM-IBP (greater than 20.1 mm Hg) was associated with a higher probability of retaining liquid bolus or barium tablet arrest on TBE and esophageal dysmotility on HRM. This finding supports the recent incorporation of IBP in Chicago Classification v4.0.

Physiologic Effects of Instilled and Aerosolized Surfactant Using a Breath-Synchronized Nebulizer on Surfactant-Deficient Rabbits

Surfactant administration incorporates liquid bolus instillation via endotracheal tube catheter and use of a mechanical ventilator. Aerosolized surfactant has generated interest and conflicting data related to dose requirements and efficacy. We hypothesized that aerosolized surfactant with a novel breath-actuated vibrating mesh nebulizer would have similar efficacy and safety as instilled surfactant. Juvenile rabbits (1.50 ± 0.20 kg, n = 17) were sedated, anesthetized, intubated, and surfactant was depleted via lung lavage on mechanical ventilation. Subjects were randomized to receive standard dose liquid instillation via catheter (n = 5); low dose surfactant (n = 5) and standard dose surfactant (n = 5) via aerosol; and descriptive controls (no treatment, n = 2). Peridosing events, disease severity and gas exchange, were recorded every 30 min for 3 h following surfactant administration. Direct-Instillation group had higher incidence for peridosing events than aerosol. Standard dose liquid and aerosol groups had greater PaO2 from pre-treatment baseline following surfactant (p < 0.05) with greater ventilation efficiency with aerosol (p < 0.05). Our study showed similar improvement in oxygenation response with greater ventilation efficiency with aerosol than liquid bolus administration at the same dose with fewer peridosing events. Breath-synchronized aerosol via nebulizer has potential as a safe, effective, and economical alternative to bolus liquid surfactant instillation.

Refractory septic shock (Part 1)

Refractory septic shock develops in 6–7% of sepsis patients with short-term lethality rate of more than 50%. It is necessary to assess the effectiveness of intensive therapy methods used in this case.The objective of the review: to analyze publications on the intensive care of refractory septic shock.Results. 56 studies published in the period from January 1, 1990 to September 1, 2020 were analysed, they reflect the effectiveness of some methods used for management of refractory septic shock (treatment of the underlying disease, liquid bolus, the use of norepinephrine, adjuvant therapy, management of metabolic acidosis). The second part of this article will reflect the evaluation of the effectiveness of other approaches to the treatment of this complication.

Jaw kinematics and tongue protraction-retraction during Chewing and drinking in the pig

Mastication and drinking are rhythmic and cyclic oral behaviors that require interactions between the tongue, jaw, and a food or liquid bolus, respectively. During mastication, the tongue transports and positions the bolus for breakdown between the teeth. During drinking, the tongue aids in ingestion and then transports the bolus to the oropharynx. The objective of this study is to compare jaw and tongue kinematics during chewing and drinking in pigs. We hypothesize there will be differences in jaw gape cycle dynamics and tongue protraction-retraction between behaviors. Mastication cycles had an extended slow-close phase, reflecting tooth-food-tooth contact, whereas drinking cycles had an extended slow-open phase, corresponding to tongue protrusion into the liquid. Compared to chewing, drinking jaw movements were of lower magnitude for all degrees of freedom examined (jaw protraction, yaw, and pitch), and were bilaterally symmetrical with virtually no yaw. The magnitude of tongue protraction-retraction (Txt), relative to a mandibular coordinate system, was greater during mastication than drinking, but there were minimal differences in the timing of maximum and minimum Txt relative to the jaw gape cycle between behaviors. However, during drinking, the tongue tip is often located outside the oral cavity for the entire cycle, leading to differences between behaviors in the timing of anterior marker maximum Txt. This demonstrates that there is variation in tongue-jaw coordination between behaviors. These results show that jaw and tongue movements vary significantly between mastication and drinking, which hint at differences in the central control of these behaviors.

Investigation of Embodied Language Processing on Command-Swallow Performance in Healthy Participants

Purpose During videofluoroscopic examination of swallowing, patients commonly are instructed to hold a bolus in their mouth until they hear a verbal instruction to swallow, which usually consists of the word swallow and is commonly referred to as the command swallow condition. The language-induced motor facilitation theory suggests that linguistic processes associated with the verbal command to swallow should facilitate the voluntary component of swallowing. As such, the purpose of the study was to examine the linguistic influences of the verbal command on swallowing. Method Twenty healthy young adult participants held a 5-ml liquid bolus in their mouth and swallowed the bolus after hearing one of five acoustic stimuli presented randomly: congruent action word ( swallow ), incongruent action word ( cough ), congruent pseudoword ( spallow ), incongruent pseudoword ( pough ), and nonverbal stimulus (1000-Hz pure tone). Suprahyoid muscle activity during swallowing was measured via surface electromyography (sEMG). Results The onset and peak sEMG latencies following the congruent action word swallow were shorter than latencies following the pure tone and pseudowords but were not different from the incongruent action word. The lack of difference between swallow and cough did not negate the positive impact of real words on timing. In contrast to expectations, sEMG activity duration and rise time were longer following the word swallow than the pure tone and pseudowords but were not different from cough . No differences were observed for peak suprahyoid muscle activity amplitude and fall times. Conclusions Language facilitation was observed in swallowing. The clinical utility of the information obtained in the study may depend on the purposes for using the command swallow and the type of patient being assessed. However, linguistic processing under the command swallow condition may alter swallow behaviors and suggests that linguistic inducement could be useful as a compensatory technique for patients with difficulty initiating oropharyngeal swallows.

The Influence of Surface Electromyography Visual and Clinician Verbal Feedback on Swallow Effort Ratio at Different Bolus Volumes in a Healthy Population

<b><i>Background/Aims:</i></b> The effortful swallow is a common treatment intervention requiring increased intensity to facilitate adaptations and modify swallow kinematics. The type of feedback and bolus volume provided may influence the intensity of the effortful swallow. To determine the increased effortful swallow intensity, a clinician can collect the peak amplitude of an effortful swallow and a typical swallow and compute a “swallow effort ratio” (SER). Dividing the effortful swallow surface electromyography (sEMG) peak amplitude by the typical swallow sEMG peak amplitude derives the SER. A higher SER suggests increased intensity. An increase in the SER may have clinical relevance in swallowing therapy as a threshold of intensity is required to elicit neuroplastic change. The purpose of this investigation was to determine whether sEMG visual and clinician verbal feedback increases the SER. Additionally, the investigation examined whether the SER is influenced by different liquid bolus volumes. <b><i>Methods:</i></b> Eighty-two nondysphagic, healthy adults were assigned at random to 2 groups. One group received no feedback, and the other received verbal and visual feedback while performing typical and effortful swallows at 3 liquid volumes. <b><i>Results:</i></b> An analysis of covariance compared the typical and effortful peak swallow amplitudes among 3 volumes in the 2 feedback groups. There was a significant effect on the peak amplitude values by feedback group <i>F</i>(2, 79) = 22.82, <i>p</i> &#x3c; 0.001. There were no differences in peak amplitude by volume regardless of feedback <i>F</i>(2, 78) = 0.413, <i>p</i> = 0.663. <b><i>Conclusion:</i></b> It appears that sEMG visual and clinician verbal feedback increases the SER, which may be a surrogate for intensity. An increased SER may have a positive effect on swallow intervention as intensity is known to influence outcomes of exercise and elicit neuroplastic change.

Jaw Kinematics and Tongue Protraction-Retraction during Chewing and Drinking in the Pig

ABSTRACTMastication and drinking are rhythmic and cyclic oral behaviors that require interactions between the tongue, jaw, and a food or liquid bolus, respectively. During mastication, the tongue transports and positions the bolus for breakdown between the teeth. During drinking, the tongue aids in ingestion and then transports the bolus to the oropharynx. The objective of this study is to compare jaw and tongue kinematics during chewing and drinking in pigs. We hypothesize there will be differences in jaw gape cycle dynamics and tongue protraction-retraction between behaviors. Mastication cycles had an extended slow-close phase, reflecting tooth-food-tooth contact, whereas drinking cycles had an extended slow-open phase, corresponding to tongue protrusion into the liquid. Drinking jaw movements were of lower magnitude for all degrees of freedom examined (jaw protraction, yaw, and pitch), and were bilaterally symmetrical with virtually no yaw. The magnitude of tongue protraction-retraction (Tx) was greater during mastication than drinking, but there were minimal differences in the timing of maximum and minimum tongue Tx relative to the jaw gape cycle between behaviors. However, during drinking, the tongue tip is often located outside the oral cavity for the entire cycle, leading to differences in behaviors in the timing of anterior marker maximum tongue Tx. This demonstrates that there is variation in tongue-jaw coordination between behaviors. These results show that jaw and tongue movements vary significantly between mastication and drinking, which hint at differences in the central control of these behaviors.Summary statementDifferences in the magnitude and timing of tongue and jaw movements and the anteroposterior positioning of the tongue during chewing and drinking demonstrate key differences in coordination of these behaviors.

Textural Changes by Mastication and Proper Food Texture for Patients with Oropharyngeal Dysphagia

Bolus texture is a key factor for safe swallowing in patients with dysphagia since an improper texture may result in aspiration and/or pharyngeal residue. This article discusses swallowing bolus texture from two key aspects: the textural change of solid food by mastication and the current standardized definition of food texture in Japan. When swallowing a liquid bolus, the texture is mostly maintained from ingestion to swallow onset. For solid food, however, the food is crushed by chewing and mixed with saliva before swallowing; the texture of the ingested food is modified to an easily swallowable form at swallow onset by mastication. Understanding the mechanism of mastication and its assessment are therefore important in deciding the proper diet for dysphagic patients. As standardized criteria for classifying the texture of food and liquid are essential as well, this report also describes the Japanese Dysphagia Diet 2013 that is commonly used as the standardized index for dysphagic diets in Japan.