https://orcid.org/0000-0002-2757-7104
Abstract
Introduction
Post-stroke dysphagia (PSD) is a widely prevalent and possibly life-threatening consequence that may lead to aspiration pneumonia, malnutrition, dehydration, and higher mortality risk. Recommending thickened fluids (TF) is a longstanding practice in the management of dysphagia. Augmenting liquid viscosity with a xanthan gum-based thickener benefits patients with PSD by aiding in the enhancement of bolus control, facilitating improved coordination in the swallowing mechanism, and lowering the risk of aspiration. Despite the widespread use of TF, limited high-quality evidence supports its benefits in PSD.
Case report
This manuscript presents the clinical experience with four varied cases of PSD. A comprehensive approach to management with TF decreased the risk of aspiration pneumonia and facilitated effective management of dietary recommendations both during hospitalization and after discharge (all Cases). In addition, TF maintained nutrition and hydration in patients with multiple hospital admissions (Case 2), maintained hydration in those unable to engage in swallow rehabilitation due to complex medical conditions (Cases 2, 3, and 4), and those who needed slow and longer recovery due to long-term risk of silent aspiration (Cases 2, 3, and 4). In one case (Case 4), the use of TF was extended for more than two years post-stroke with no reported incidence of chest infection.
Conclusion
In routine clinical practice, a comprehensive management approach with xanthan gum-based TFs reduces the risk of aspiration and aspiration pneumonia in patients with PSD while maintaining nutritional and hydration and improving swallowing function based on formal instrumental assessments. This clinical experience highlights the pivotal role of instrumental assessment, patient education, and informed decision-making to optimize outcomes with TF.
1. Introduction
Post-stroke oropharyngeal dysphagia (PSD) occurs in up to 45% of patients with stroke. Up to 45% of post-stroke individuals endure oropharyngeal dysphagia within the first few days or weeks after the cerebrovascular incidentCitation1,Citation2, and nearly 11-50% of the patients exhibiting symptoms up to six months after the incidentCitation3. PSD affects the coordination, sensation, and strength of muscles used in swallowing, leading to difficulties in oral preparatory and propulsive phases of swallowing, pharyngeal transit, and esophageal motilityCitation4. The consequences of PSD are profound, including increased risks of aspiration pneumonia, pulmonary infection, malnutrition, dehydration and adversely affecting their quality of lifeCitation3,Citation5. PSD is associated with an increased hospital stay and higher mortality rate; previous reports showed that the mortality rate among stroke survivors with PSD is 30%Citation6, especially with severe dysphagia requiring tube placementCitation7. Patients with PSD were also found to have severe impairments in their quality of life (QoL), with 41% of patients experiencing panic or anxiety during eatingCitation8. In addition, PSD significantly increases healthcare resource utilization and overall medical costsCitation9. Three months post-stroke, patients with PSD had poorer outcomes and were less likely to live at homeCitation7.
Effective management of PSD is a cornerstone in the continuum of care after a stroke. In recent years, there has been significant advances in the management of PSDCitation10,Citation11. Speech-language therapists (SLTs) have a crucial role in mitigating and preventing these complications through early intervention strategiesCitation12. Treatment for dysphagia can be broadly categorized into two approaches: compensatory methods, which yield immediate improvements in swallow safety and efficacy, and rehabilitative methods, designed to bring about longer-term changes in swallowing physiologyCitation13. Various rehabilitative methods are employed to improve swallowing function and reduce the risk of complications. These techniques often include prophylactic swallow exercises, such as the Shaker exercise, Chin tuck against resistance (CTAR), and Masako maneuver, designed to strengthen the tongue, improve pharyngeal contraction and laryngeal elevationCitation14. Additionally, neuromuscular electrical stimulation (NMES) and surface electromyography (sEMG) are often used in conjunction with these exercises to provide further muscle stimulation and biofeedback, respectivelyCitation15. Other rehabilitative methods include but are not limited to transcranial direct current stimulation (tDCS), pharyngeal electrical stimulation (PES), rehabilitative oral trials and thermal tactile stimulation (TTS)Citation16.
Management of PSD in clinical settings most often focuses on compensatory methods to enhance patient safety during the period of spontaneous recovery, typically employing techniques such as texture-modified foods, thickened fluids (TF), positioning, and swallowing maneuvers (e.g. effortful swallowing)Citation13,Citation17. In more severe cases, alternative feeding methods like nasogastric tubes (NG) or percutaneous endoscopic gastrostomy (PEG) may be necessaryCitation18. The practice of prescribing TF for patients with PSD is a standard practice among SLTs. Literature evidence shows that 78% of SLTs in the United Kingdom (UK) and IrelandCitation19 and 94.07% of SLTs in Australia recommend TF for patients with dysphagia to reduce the risk of aspirationCitation13. Augmenting liquid viscosity may benefit individuals with PSD by aiding in the enhancement of bolus control, facilitating improved coordination in the swallowing mechanism, and lowering the risk of aspirationCitation20, especially for those with impaired sensory and motor controlCitation21. Recommended drink thickness in the UK is based on the International Dysphagia Diet Standardization Initiative (IDDSI) and can be between Level 1-4 of the IDDSI frameworkCitation22. Typically, the consistency of the TF is tailored to the patient based on swallowing physiology and dysphagia severityCitation23. However, despite the widespread use of TF for patients with dysphagia, there is a lack of international consensus on the standards of their use. In addition, limited high-quality evidence, such as randomized control trials, supports the benefits of TF in PSDCitation24.
The present manuscript presents a real-world clinical experience with the management of PSD, beginning in an acute stroke ward and continued care in the community. The manuscript explored the clinical benefits of TF in patients with PSD, focusing on their impact on reducing the risk of aspiration. In addition, the value of instrumental assessments of patients with PSD was highlighted to understand their swallow physiology before recommending TF.
2. Case report
Verbal consent was obtained from all four participants or next of kin via telephone for the publication of this manuscript. The study was considered a service evaluation based on the UK Policy Framework for Health and Social Care Research decision tool, and the protocol was not classified as research according to the National Health System (NHS) research and development team. Hence, the need for approval from the local ethics committee was waived.
2.1. Case 1: Oropharyngeal dysphagia post-parietal intracranial hemorrhage (ICH)
A 75-year-old female was admitted to the hospital after a collapse at home with reduced consciousness, and a tonic-clonic seizure. The patient was intubated upon admission and underwent an urgent head computed tomography (CT) scan, which revealed a right parietal ICH with potential extension into the subarachnoid and subdural spaces. Prior to admission, the patient was active and living independently. Her past medical history showed hypertension, impaired glucose tolerance, and hypercholesterolemia. The patient weighed 56.8 Kg on admission.
The patient was extubated five days post-stroke and, approximately 24 h post-extubation, was alert for a bedside swallowing assessment by SLT. Her voice was aphonic, indicative of possible laryngeal trauma from endotracheal intubation, with occasional brief vocalizations. Bedside assessment indicated that she remained at risk of aspiration on all oral intake, and an NG tube was inserted to maintain her nutritional needs. Subsequent assessments, at the third- and ninth-day post-stroke, revealed similar findings. The patient continued to show subtle overt signs such as a wet voice with normal fluids and an IDDSI level 4-pureed diet. Such findings suggested suspected silent aspiration and an instrumental assessment was indicated.
While waiting for the instrumental assessment, the patient showed a spontaneous recovery of vocal quality, phonatory strength, and vocal loudness. Thus, a repeated bedside assessment was performed 12 days post-stroke that showed improved swallowing and better tolerance to IDDSI level 4 pureed diet. The patient also expressed a strong intent towards oral intake. Hence, swallow rehabilitation trials of five teaspoons of IDDSI level 4 diet/level 4-extremely thick fluids were started three times a day. During these trials, markers of respiratory and systemic infections were monitored. The patient progressed well with her swallow rehabilitation trials, with no observed signs of respiratory infection.
The patient underwent a video-fluoroscopy (VFS) one month after the stroke, which showed moderate oropharyngeal dysphagia, a reduced tongue base retraction, pharyngeal contraction, laryngeal elevation, and hyoid excursion causing impaired airway closure during the swallow. Although the patient tolerated small quantities of Level 4 Puree, increased intake led to fatigue. Silent penetration into the laryngeal vestibule was noted with IDDSI level 2 (mildly thick fluids) (PAS = 3), level 4 Puree (PAS = 5), and level 5 minced and moist diet (PAS =5) consistencies. The only safe consistency identified was IDDSI level 3 fluids (moderately thick) (PAS = 1) despite the effect of fatigue. The SLT recommended IDDSI level 3 fluids (4.8 g (4 scoops) of ThickenUp® Clear, Nestlé Health Science, per 200 mL) and level 3 liquidized diet alongside behavioral swallow rehabilitation (such as CTAR, Masako, Shakers, and Super-supraglottic swallow) for 15 min, five times daily.
One week after the VFS, the patient had full portions of level 3 meals with good tolerance. The NG tube was removed, and the patient maintained her nutritional needs orally. She was started on an IDDSI level 3 oral nutritional supplement (ONS) by dietetics to supplement oral intake and maintain her weight. Upon discharge, the patient weighed 59 Kg, representing an increase of 2.3 Kg at admission. She continued her behavioral rehabilitation program at home with follow-up from community SLT.
The patient underwent a follow-up VFS one month after discharge, which showed further improvements. She still exhibited reduced pharyngeal contraction, leading to a vallecular residue with the potential for silent aspiration with thinner fluids, necessitating caution when considering a reduction in thickening agents. She returned to a normal diet with the need to continue IDDSI level 2 fluids (2.4 g (2 scoops) ThickenUp® Clear, Nestlé Health Science, per 200 mL). Two weeks after the follow-up VFS, no signs of respiratory or urinary infections were reported while the patient continued the IDDSI level 2 TF. In addition, her weight was maintained at 59 Kg, and the ONS was stopped.
A follow-up VFS was performed seven weeks after prescribing IDDSI level 2 fluids. The assessment showed significant improvement in the swallowing function, with residual mild pharyngeal dysphagia. There were no signs of airway penetration; however, some vallecular residue remained and cleared effectively with repeated clearance swallows. The patient was recommended a normal diet and fluids. At the six-month stroke review, the patient showed complete recovery from the stroke and continued normal diet and fluids with no difficulties.
2.2. Case 2: Oropharyngeal dysphagia post-cerebellar stroke
A previously independent and active 64-year-old male with a history of hypertension, high cholesterol, and chronic obstructive pulmonary disease (COPD) presented to the emergency department (ED) after a fall at home. He experienced acute vertigo, slurred speech, and unsteadiness for two days. Physical examination revealed truncal ataxia, dysdiadokokinesia, and left eye ptosis. CT head showed a large acute infarction in the infero-medial right cerebellar hemisphere, consistent with a right posterior circulation syndrome.
Within the first 24 h, bedside SLT assessment identified severe oropharyngeal dysphagia and poor secretion management. An NG tube was inserted for nutritional needs. A fiber-optic endoscopic evaluation of swallow (FEES) on the fifth day revealed impaired pharyngeal and laryngeal sensation, reduced epiglottic deflection, and diminished upper esophageal sphincter opening, resulting in significant pharyngeal residue, silent airway penetration, and aspiration. A diagnosis of severe pharyngeal dysphagia with a high aspiration risk was established with a PAS score of 8 across consistencies, recommending continued NG feeding.
After the FEES, the patient was initiated on a CTAR rehabilitation program for two weeks. CTAR was performed 5 times per day for 10 mins (5 trials of 60 s resistance with 60 s of break). Due to increasing anxiety about his dysphagia and having distressing thoughts, the patient was referred to clinical psychology and received continuous psychological support during his hospitalization.
On the follow-up FEES assessment 20 days post-stroke, significant improvements were noted in the observed impairments. The patient was recommended IDDSI level 2 fluids (2.4 g (2 scoops) ThickenUp® Clear, Nestlé Health Science, per 200 mL) and IDDSI level 6-soft and bite-sized diet (PAS score of 1 on both these consistencies). CTAR rehabilitation program was continued using the same regimen. The initiation of the oral intake led to significant improvement in the psychological well-being of the patient based on the psychologist’s assessment. The patient was able to fulfil his nutritional needs on a modified diet and fluids, and the NG tube was removed 3 days after the FEES. A follow-up FEES a week later revealed no notable improvement, with continued silent aspiration (PAS = 8) on Level 0 and 1 fluids, and Level 7 diet. He was discharged a month post-stroke and exhibited no signs of chest infections, dehydration, or issues related to the prescribed dietary modifications.
Unfortunately, within a month of discharge, the patient experienced an out-of-hospital cardiac arrest and was admitted to the cardiac care unit in the hospital. The patient was placed on NG feeding and intravenous (IV) antibiotics due to reduced alertness and aspiration pneumonia. A FEES assessment two weeks after cardiac arrest indicated improvements in swallowing, and the patient was again commenced on IDDSI level 2 fluids and level 6 diet. Due to fatigue and medical status, the patient was unable to eat full portions of meals and needed supplemental NG feeding. One and a half months after his cardiac arrest, the patient was able to meet his nutritional needs orally, and the NG was removed. He was offered behavioral rehabilitation for his swallow through his admission; however, he declined again owing to ongoing low mood and psychological difficulties. Further psychological support was provided to the patient whilst he was an inpatient.
The patient then underwent a valve replacement surgery two months after his cardiac arrest, around 4 months after his initial stroke. A VFS was conducted after recovery from surgery and showed ongoing silent aspiration with normal fluids and IDDSI level 1 fluids; however, he was able to start on normal diet textures. He was, therefore, recommended to continue IDDSI level 2 fluids and discharged from the hospital.
Due to an unpleasant sensory experience with TF, eating and drinking with acknowledged risk was discussed as an option with the patient, providing him with the choice of returning to normal fluids. The risks of silent aspiration and aspiration pneumonia were explained to the patient, and he made the informed decision to continue level 2 fluids. Two months after his discharge, the patient’s psychological well-being improved, and he expressed his willingness to start rehabilitation. He was offered a block of expiratory muscle strength training (EMST) for six weeks to increase muscle strength and improve airway protection. Once the EMST block was completed, a follow-up VFS showed improved pharyngeal functioning and no significant airway penetration with thin fluids. The patient successfully returned to the pre-stroke baseline normal diet, fluids, and daily activities 6 months after his stroke.
2.3. Case 3: Oropharyngeal dysphagia post-large left cerebral hemorrhage
A 74-year-old female was admitted to the hospital with right-sided weakness, dysarthria, and dysphasia. The MRI scan identified a large left cerebral hemorrhage with ventricular extension and significant mass effect. The patient was treated with conservative approaches.
The initial bedside swallow assessment revealed a high risk of aspiration on all oral intake, indicative of severe oropharyngeal dysphagia, and commenced on NG feeding for all nutritional intake. The speech and language assessment also revealed severe receptive and expressive aphasia, with verbal communication limited to occasional single-word production. In addition, the patient demonstrated variable levels of alertness and fatigue throughout the initial few days of recovery from the stroke and was treated with antibiotics for two episodes of aspiration pneumonia.
The patient’s level of alertness and fatigue continued to fluctuate a month after the stroke. A FEES assessment was performed one and a half months post-stroke to determine if there were any safe textures that the patient could have for pleasure when she was less fatigued and alert to engage. The assessment showed moderately-impaired pharyngeal swallow exacerbated by fatigue. Aspiration was observed with IDDSI level 0 fluid (PAS = 8) and airway penetration with IDDSI 4 (PAS = 3), but she tolerated Level 2 fluids (PAS = 1). The patient did not respond to penetrated or aspirated material, which suggested sensory impairment and risk of silent aspiration; however, she was able to clear penetration with level 4 with additional spontaneous clearing swallows. She was commenced on oral trials up to 10 teaspoons of IDDSI level 2 fluids (2.4 g (2 scoops) ThickenUp® Clear, Nestlé Health Science, per 200 mL of fluids) or IDDSI Level 4 pureed diet, up to 5 times a day for swallow rehabilitation and for pleasure when awake and alert.
Since the patient was unlikely to meet her nutritional needs orally, a long-term nutritional plan was implemented, and a PEG was inserted. The patient continued her oral trials for clinical, psychological, and quality of life benefits and was discharged two months post-stroke. She continued to receive feed via the PEG according to the regime recommended by the dietician to meet her nutritional requirements. Despite extensive speech and language rehabilitation, she continued to have significant dysphasia, which limited her active participation in direct behavioral therapy for swallow.
Three and a half months post-stroke, the patient started to show some intolerance to PEG feeds and had severe vomiting on several occasions. Due to noted issues with feed tolerance, the patient’s family was keen that the patient eat more orally and continued to encourage oral intake. Full portions of a texture-modified diet (IDDSI level 4) and TF (IDDSI level 2) with overnight feeding through PEG to achieve nutritional needs were prescribed. Four and half months post-stroke, the patient continued to have 2 small meals per day of IDDSI level 4 pureed meals and level 2 fluids without any signs of aspiration or worsening of chest symptoms and without any sign of dehydration and malnutrition. The patient was upgraded to IDDSI level 5 minced and moist diet six months post-stroke to provide her with more options of texture. To maintain her nutritional status, she still received overnight feeding and nutritional supplements via her PEG.
The patient’s health and severity of difficulties meant that her oral intake always remained variable several months post-stroke. The dieticians slowly tapered the amount of nutrition provided through the PEG until 10 months post-stroke. A repeat VFS at this stage revealed that the patient could now tolerate normal diet textures without any difficulties; however, due to delayed initiation of swallow and delayed epiglottic deflection, she was still at risk of silent aspiration with thin fluids. The patient was upgraded to IDDSI level 1 fluids (1.2 g (1 scoop) ThickenUp® Clear per 200 mL) and level 7 regular diet. Her PEG feeds were stopped four months after her repeat VFS once she was able to fulfil her nutritional needs orally. Her PEG was removed 15 months post-stroke, and she continues to tolerate Level 1 fluids and a normal diet without any difficulties, awaiting a further follow up VFS.
2.4. Case 4: Oropharyngeal dysphagia post-left lacunar infarct
A 92-year-old female was admitted to the hospital with dysarthria and right facial droop. CT head revealed a left lacunar infarct. She had a complex past medical history of atrial fibrillation, hypertension, osteoarthritis, hypercholesterolemia, abdominal aortic aneurysm, chronic kidney disease (CKD) stage 3, gall bladder stones, hiatus hernia, and registered blindness. She also had significant cognitive difficulties and severe hearing impairment. She was living in a care home and was housebound.
On initial bedside swallow assessment, the patient was diagnosed with moderate oropharyngeal dysphagia with observed coughing with thinner fluids and difficulties with mastication of chewier diet textures. She tolerated IDDSI level 2 fluids (2.4 g ThickenUp® Clear, Nestlé Health Science per 200 mL) and IDDSI level 5 diet. A repeated bedside assessment four days post-stroke showed no notable change in swallowing. One-week post-stroke, the patient was discharged from the hospital with sustained swallowing difficulties as she could not engage in any formal swallow rehabilitation due to her age, cognitive difficulties, and complex medical history. A repeated assessment after discharge, at 1.5 months and 2 months, showed no changes in the swallowing functions. Notably, the patient maintained her weight according to the care home, and there were no reports of chest infections or dehydration.
Four months post-stroke, carers reported a reduction in fluid intake due to the patient reporting an unpleasant taste of TF. SLT trialed thinner fluids to assess for safety, and the patient appeared safe on small quantities of level 1 fluids (1.2 g (1 scoop) ThickenUp® Clear per 200 mL) controlled sips with supervision via a spouted beaker. One week after the upgrade, a re-assessment revealed subtle signs of aspiration, such as a wet voice post-swallow. Thus, the SLT downgraded the patient to Level 2 fluids again, and the patient was referred for a VFS to identify safe diet and fluid consistencies. Care home staff were asked to regularly encourage TF by providing flavored drinks of the patient’s choice and cold drinks for a pleasant experience.
The VFS, conducted six months post-stroke, showed moderate oropharyngeal dysphagia characterized by a delayed swallow trigger, reduced laryngeal excursion, and residue post-swallow. The patient was still at risk of silent aspiration on IDDSI levels 0 and 1 fluids (PAS = 8). She was recommended to continue level 2 fluids (2.4 g ThickenUp® Clear, Nestlé Health Science per 200 mL). During the examination, she appeared to manage IDDSI level 6 (PAS = 2) without aspiration, and she was recommended to try a careful upgrade to this consistency. Due to concerns about reduced fluid intake, eating and drinking with acknowledge risk was discussed with the family. The family chose for the patient to continue with Level 2 fluids and agreed to attempt and encourage fluid intake with other flavored drinks, naturally thick fluids, and water-rich food items.
The patient continued on IDDSI level 6 diet and level 2 fluids safely, without any chest infections or issues with tolerance of thickener. She was monitored by the community SLT for a month after the VFS and was then discharged from the service. The patient was re-referred one year and nine months post-stroke again for a re-assessment, and a repeat video-fluoroscopy assessment revealed that her swallow remained the same with no significant improvement from baseline. Thus, she continued on IDDSI level 2 fluids and a level 6 soft and bite-sized diet.
3. Discussion
This case report described four cases from clinical practice with the most commonly used compensatory treatment for PSD which is the prescription of thickened fluids. However, there is limited literature evidence that suggests that TFs reduce the risk of aspiration in PSDCitation25 due to the lack of well-designed trials evaluating TF outcomes in patients with dysphagiaCitation24,Citation26. Thus, real-world clinical experiences are crucial to understanding TF's benefits and its limitations in routine practice.
According to McCurtin et al. the majority of SLT respondents hold core underlying beliefs regarding the use of TL, which are primarily grounded in evidence from clinical practice. Factor analysis suggests that respondents perceive TL as the most effective treatment for aspiration and believe in its efficacy, stating that "it works”Citation27. In keeping with this belief, in all four presented patients, there were no reported incidences of chest infections while receiving TF. Patients who need more time to recover due to multiple admissions (Case 2) or long-term risk of silent aspiration and more severe dysphagia (Case 3) maintained their chest status and did not show any signs of chest infections in acute settings or when discharged into the community. Although patients in Case 2 and 4, both experienced an unpleasant taste with TF, the patient and family made an informed decision to continue TF to mitigate the risk of aspiration and prioritizing chest safety. In patient 4 (Case 4), the use of TF was extended for more than two years post-stroke, with no reported incidence of chest infection. This observation aligns with a growing body of research indicating the effectiveness of xanthan gum-based thickener in reducing the risk of aspiration in a viscosity-dependent mannerCitation28,Citation29. Recently, a pooled analysis of two large datasets (n = 11592 bolus from 855 adults) demonstrated that xanthan-gum or scratch TF was associated with a lower risk of penetration-aspiration compared to thin liquids. The Penetration-Aspiration Scale (PAS) scores were consistently higher in the thin liquids group compared to mildly, moderately, and extremely thick consistenciesCitation30.
Silent aspiration poses a significant risk in patients with PSD due to the absence of cough response or visible signs of swallowing difficulty and accounts for nearly 20% of the deaths in post-stroke patientsCitation31,Citation32. In a study that evaluated 42 PSD patients, the predominant anomaly observed in this examination was an abnormal cough reflex, noted in 77.1% of casesCitation33. Silent aspiration has been reported in over 40% of dysphagic patients, highlighting its prevalenceCitation34. All four presented patients showed signs of silent aspiration on one or more consistencies of diet or fluid. This evidence underscores the necessity of instrumental assessments, such as VFS and FEES, which play a crucial role in dysphagia management by providing a dynamic assessment of the swallowing process to detect silent aspirationCitation35 and ensuring that the increased liquid viscosity does not impede the swallowing process or lead to other complications. VFS shows high accuracy in detecting silent aspirationCitation31,Citation32, and FEES is particularly useful for identifying pharyngeal residue and assessing laryngeal sensitivity in patientsCitation36. Overly thickened liquids, though intended to reduce aspiration risk, can paradoxically lead to complications as they may increase oral and pharyngeal residue, lead to difficulties with bolus transfer due to reduced tongue or pharyngeal strength, and make it difficult to expel aspirated materialCitation37. Despite the need for instrumental assessments, recent reports highlighted that SLTs mainly rely on clinical findings to recommend TF without instrumental assessmentCitation27; this is likely due to the lack of access to instrumental assessments or the capacity to complete these assessments in clinical time. In the presented four cases, all patients waited a significant time to receive an initial instrumental assessment or a repeated assessment due to acute and community waitlists. These constraints are common in clinical settings.
All four patients presented were placed ‘Nil by mouth’ on initial assessment by SLT due to their severity of dysphagia and commenced on tube feeding. Prolonged tube feeding in patients with PSD can introduce several challenges, including an increased risk of aspiration leading to chest infections and a higher risk of mortalityCitation7,Citation38. It is also suggested that NG tube placement elevates pneumonia risk by inducing the growth of pathogenic bacteria in the oropharynxCitation39,Citation40. Additionally, tube feeding can cause negative psychological impacts on patients due to perceived regression or lack of progressCitation41,Citation42. Moreover, this early phase of being nil by mouth may restrict the opportunity for recruitment and remodeling of neural networks in contralateral brain areas, as well as access to neural adaptability. When thin liquids and solid foods pose significant risk of aspiration, TL and modified diets may be provided as an alternative to being nil by mouth with tube feeding increasing the feasibility of oral trials in the PSD population for early rehabilitation. According to literature evidence, 'swallow trials’ are advised 'often or always’ by 73% of SLTs involved in stroke rehabilitationCitation43. In cases 1 and 2, swallow trials of modified diet textures and TFs were used as a form of rehabilitation. In case 3, the patient also had periods where she could not tolerate PEG feeding in the community and needed oral feeding to maintain nutrition and hydration when PEG feeding needed stopping. This was only achieved safely using TF and modified diet textures. By providing a consistent method of nutritional support, TFs ensure that patients receive adequate nutrition without the complications of alternative feeding methods.
PSD rehabilitation aims to enhance swallowing function and enable safer oral intake. However, there is a significant gap in comprehensive evidence supporting these therapiesCitation44. The current evidence base around rehabilitative approaches such as oral trials, NMES, tDCS, PES, and sEMG for PSD is still developing; there is a lack of well-designed, large scale studies assessing the most appropriate treatment for specific patients, including the optimal dosage and intensity of each therapy approachCitation45. This uncertainty complicates the implementation of rehabilitative therapies in clinical practice and the decision-making process for SLTCitation45, and it remains unclear how clinicians weigh different factors in their treatment decisions for PSD. Additionally, in routine practice, several barriers can be faced when initiating rehabilitative methods, such as overall health conditions, cognitive impairments, variability in clinical decision-making, and financial constraints within the healthcare systemCitation46. In the current clinical experience, three patients were not able to engage in swallow rehabilitation due to psychological reasons (Case 2), severe receptive and expressive aphasia (Case 3), or age and associated comorbidities (Case 4). This ambiguity in current clinical practice underscores the necessity of using TFs as part of PSD management.
Ultimately, a patient-centered approach is recommended to ensure shared and informed decision-making; through this approach, the SLT should supply patients with PSD with accurate information about TF benefits and potential issuesCitation27,Citation47. The altered consistency of fluid using thickening agents can be less appealing and less enjoyable to drink than natural drinks, affecting the taste perception depending on the thickening agent usedCitation48. Additionally, TF (IDDSI Level 3 and Level 4) are often taken with a spoon, which deviates from the usual or normal practice of drinking it freely. The confluence of these factors can lead to patient aversion towards the consumption of thickened liquids and poor adherenceCitation49, reduced intake, dehydration, malnutrition, and impaired QoLCitation47. Two cases (Cases 2 and 4) initially developed an aversion towards drinking due to the unpleasant sensations associated with the use of TF. However, after a detailed session with an SLT explaining the rationale for the treatment along with the benefits and issues of thickened drinks, the potential risk of silent aspiration, and ensuring a process of shared decision-making, the patient and their families agreed to continue with the recommended TF. In addition, patients and families were educated on using different recipes and flavors that can improve the palatability of TF. It is also recommended that a thickening agent be prescribed that exerts minimal impact on the taste, odor, and color of the thickened beverage.
This approach aims to enhance patient compliance and optimize the desired therapeutic outcomes. Xanthan gum-based thickener, which has been used in the four cases, is an acceptable and appealing thickening agent compared to other agentsCitation50,Citation51. Other studies also showed that the xanthan gum-based thickener is associated with a high degree of satisfaction and good compliance due to its excellent gastrointestinal tolerance, wide versatility in use with different beverages, and more transparency than the other thickeners, making it a more appealing optionCitation52,Citation53. In the current clinical experience, all patients were able to efficiently manage their dietary recommendations as recommended by the SLT and dietitian, both in the hospital and when discharged home. There were no reported issues with dehydration among the four patients as well. In one patient (Case 1), there was even an increase in body weight by 2.3 Kg at discharge, and the patient maintained her weight during the follow-up visits whilst on Level 3 liquidized diet and Level 3 fluids. Such findings highlight the importance of patient education and shared decision-making.
Despite the benefits of TF for PSD management, several gaps exist in treating this condition that warrant further research. One significant gap is the lack of standardized TF protocols for PSD patients, balancing the benefits and potential risks of TF intervention. Additionally, most SLTs rely on clinical findings rather than instrumental assessments to recommend TFCitation27. There is also a lack of objective measures to evaluate the success of TF intervention, and future research should aim to develop standardized tools, such as physiological measures and patient-reported outcomes, for evaluating TF outcomes. The immediate and prolonged impacts of thickened fluids on significant clinical outcomes, including mortality, morbidity, and health-related quality of life, as perceived by patients in terms of their well-being, functional abilities, and overall survival, need to be evaluated furtherCitation54. Although the current clinical experience supports the clinical benefits of TF, it is limited by being a retrospective chart review and only of a small number of patients. The retrospective nature of the study also hinders the utilization of patient-reported measures to assess patient experience with TF.
4. Conclusion
In routine clinical practice, a comprehensive management approach with a xanthan gum-based TF reduces the risk of aspiration and aspiration pneumonia among patients with PSD and improves swallowing function when prescribed based on formal instrumental assessments. Clinical and/or instrumental assessments, as well as patient education regarding the benefits of treatment adherence, play a crucial role in optimizing the outcomes of PSD. Furthermore, the empowerment of patients through informed decision-making is vital to optimize outcomes related to TFs. Further research is required to obtain patient’s self-reported quality-of-life measures concerning the use of TFs for dysphagia management in PSD.
Transparency
Declaration of funding
Declaration of financial/other relationships
SV received honoraria from Nestlé Health Science for the development of the present manuscript. The author was sponsored by Nestlé Health Science to attend the 2023 ESSD conference in France. Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.
Author contributions
SV was involved in the writing of clinical cases, discussion, and conclusion. They also contributed to patient care.
Acknowledgments
The author acknowledges the patients and their families and the healthcare professionals at the affiliation center. Medical writing and editorial support in preparing this paper were provided by Content Ed Net Switzerland.
Additional information
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References
- Takizawa C, Gemmell E, Kenworthy J, et al. A systematic review of the prevalence of oropharyngeal dysphagia in stroke, parkinson’s disease, alzheimer’s disease, head injury, and pneumonia. Dysphagia. 2016;31(3):434–441. doi:10.1007/s00455-016-9695-9.
- Singh S, Hamdy S. Dysphagia in stroke patients. Postgrad Med J. 2006;82(968):383–391. https://academic.oup.com/pmj/article/82/968/383/7045298.
- Cohen DL, Roffe C, Beavan J, et al. Post-stroke dysphagia: a review and design considerations for future trials. Int J Stroke. 2016;11(4):399–411. doi:10.1177/1747493016639057.
- González-Fernández M, Ottenstein L, Atanelov L, et al. Dysphagia after stroke: an overview. Curr Phys Med Rehabil Rep. 2013;1(3):187–196. doi:10.1007/s40141-013-0017-y.
- Clavé P, Shaker R. Dysphagia: current reality and scope of the problem. Nat Rev Gastroenterol Hepatol. 2015;12(5):259–270. doi:10.1038/nrgastro.2015.49.
- Smithard DG, O'Neill PA, Parks C, et al. Complications and outcome after acute stroke: does dysphagia matter? Stroke. 1996;27(7):1200–1204. doi:10.1161/01.str.27.7.1200.
- Arnold M, Liesirova K, Broeg-Morvay A, et al. Dysphagia in acute stroke: incidence, burden and impact on clinical outcome. PLoS One. 2016;11(2):e0148424. doi:10.1371/journal.pone.0148424.
- Ekberg O, Hamdy S, Woisard V, et al. Social and psychological burden of dysphagia: its impact on diagnosis and treatment. Dysphagia. 2002;17(2):139–146. doi:10.1007/s00455-001-0113-5.
- Labeit B, Kremer A, Muhle P, et al. Costs of post-stroke dysphagia during acute hospitalization from a health-insurance perspective. Eur Stroke J. 2023;8(1):361–369. doi:10.1177/23969873221147740.
- Alamer A, Melese H, Nigussie F. Effectiveness of neuromuscular electrical stimulation on post-stroke dysphagia: a systematic review of randomized controlled trials. Clin Interv Aging. 2020;15:1521–1531. doi:10.2147/CIA.S262596.
- Diéguez-Pérez I, Leirós-Rodríguez R. Effectiveness of different application parameters of neuromuscular electrical stimulation for the treatment of dysphagia after a stroke: a systematic review. J Clin Med. 2020;9(8):1–19.
- Carnaby G, Hankey GJ, Pizzi J. Behavioural intervention for dysphagia in acute stroke: a randomised controlled trial. Lancet Neurol. 2006;5(1):31–37. doi:10.1016/S1474-4422(05)70252-0.
- Jones O, Cartwright J, Whitworth A, et al. Dysphagia therapy post stroke: an exploration of the practices and clinical decision-making of speech-language pathologists in Australia. Int J Speech Lang Pathol. 2018;20(2):226–237. doi:10.1080/17549507.2016.1265588.
- Krekeler BN, Rowe LM, Connor NP. Dose in exercise-based dysphagia therapies: a scoping review. Dysphagia. 2021;36(1):1–32. doi:10.1007/s00455-020-10104-3.
- Tarihci Cakmak E, Sen EI, Doruk C, et al. The effects of neuromuscular electrical stimulation on swallowing functions in post-stroke dysphagia: a randomized controlled trial. Dysphagia. 2023;38(3):874–885. doi:10.1007/s00455-022-10512-7.
- Wirth R, Dziewas R, Beck AM, et al. Oropharyngeal dysphagia in older persons – from pathophysiology to adequate intervention: a review and summary of an international expert meeting. Clin Interv Aging. 2016;11:189–208. doi:10.2147/CIA.S97481.
- Bath PM, Lee HS, Everton LF. Swallowing therapy for dysphagia in acute and subacute stroke. Cochrane Database Syst. Rev. 2018.
- Dennis MS, Lewis SC, Warlow C, FOOD Trial Collaboration. Effect of timing and method of enteral tube feeding for dysphagic stroke patients (FOOD): a multicentre randomised controlled trial. Lancet. 2005;365(9461):764–772. doi:10.1016/S0140-6736(05)17983-5.
- McCurtin A, Healy C. Why do clinicians choose the therapies and techniques they do? Exploring clinical decision-making via treatment selections in dysphagia practice. Int J Speech Lang Pathol. 2017;19(1):69–76. doi:10.3109/17549507.2016.1159333.
- Dantas RO, Kern MK, Massey BT, et al. Effect of swallowed bolus variables on oral and pharyngeal phases of swallowing. Am J Physiol Gastrointest Liver Physiol. 1990;258:G675–G681.
- Clavé P, De Kraa M, Arreola V, et al. The effect of bolus viscosity on swallowing function in neurogenic dysphagia. Aliment Pharmacol Ther. 2006;24(9):1385–1394. doi:10.1111/j.1365-2036.2006.03118.x.
- Cichero JAY, Lam P, Steele CM, et al. Development of international terminology and definitions for texture-modified foods and thickened fluids used in dysphagia management: the IDDSI framework. Dysphagia. 2017;32(2):293–314. doi:10.1007/s00455-016-9758-y.
- Cichero JAY. Thickening agents used for dysphagia management: effect on bioavailability of water, medication and feelings of satiety. Nutr J. 2013;12(1):54. doi:10.1186/1475-2891-12-54.
- Hansen T, Beck AM, Kjaersgaard A, et al. Second update of a systematic review and evidence-based recommendations on texture modified foods and thickened liquids for adults (above 17 years) with oropharyngeal dysphagia. Clin Nutr ESPEN. 2022;49:551–555. doi:10.1016/j.clnesp.2022.03.039.
- Newman R, Vilardell N, Clavé P, et al. Effect of bolus viscosity on the safety and efficacy of swallowing and the kinematics of the swallow response in patients with oropharyngeal dysphagia: white paper by the European Society for Swallowing Disorders (ESSD). Dysphagia. 2016;31(2):232–249. doi:10.1007/s00455-016-9696-8.
- Lazenby-Paterson T. Thickened liquids: do they still have a place in the dysphagia toolkit? Curr Opin Otolaryngol Head Neck Surg. 2020;28(3):145–154. doi:10.1097/MOO.0000000000000622.
- McCurtin A, Byrne H, Collins L, et al. Alterations and preservations: practices and perspectives of speech-language pathologists regarding the intervention of thickened liquids for swallowing problems. Am J Speech Lang Pathol. 2023;33(1):117–134. http://pubs.asha.org/doi/10.1044/2023_AJSLP-23-00226. doi:10.1044/2023_AJSLP-23-00226.
- Bolivar-Prados M, Rofes L, Arreola V, et al. Effect of a gum-based thickener on the safety of swallowing in patients with poststroke oropharyngeal dysphagia. Neurogastroenterol Motil. 2019;31(11):e13695. doi:10.1111/nmo.13695.
- Bolivar-Prados M, Hayakawa Y, Tomsen N, et al. Shear-viscosity-dependent effect of a gum-based thickening product on the safety of swallowing in older patients with severe oropharyngeal dysphagia. Nutrients. 2023;15(14):15. doi:10.3390/nu15143279.
- Borders JC, Steele CM. The effect of liquid consistency on penetration-aspiration: a Bayesian analysis of two large datasets. Front Rehabil Sci. 2024;5:1337971. https://www.frontiersin.org/articles/10.3389/fresc.2024.1337971/full. doi:10.3389/fresc.2024.1337971.
- Giraldo-Cadavid LF, Leal-Leaño LR, Leon-Basantes GA, et al. Accuracy of endoscopic and videofluoroscopic evaluations of swallowing for oropharyngeal dysphagia. Laryngoscope. 2017;127(9):2002–2010. doi:10.1002/lary.26419.
- Carucci LR, Ann Turner M. Dysphagia revisited: common and unusual causes. Radiographics. 2015;35(1):105–122. doi:10.1148/rg.351130150.
- Tamin S, Marpaung D, Sitorus F. Increasing risk of silent aspiration in stroke patients. J Exp Clin Med. 2023;40(2):364–369.
- Leder SB, Cohn SM, Moller BA. Fiberoptic endoscopic documentation of the high incidence of aspiration following extubation in critically ill trauma patients. Dysphagia. 1998;13(4):208–212. doi:10.1007/PL00009573.
- Helliwell K, Hughes VJ, Bennion CM, et al. The use of videofluoroscopy (VFS) and fibreoptic endoscopic evaluation of swallowing (FEES) in the investigation of oropharyngeal dysphagia in stroke patients: a narrative review. Radiography. 2023;29(2):284–290. doi:10.1016/j.radi.2022.12.007.
- Fattori B, Giusti P, Mancini V, et al. Comparison between videofluoroscopy, fiberoptic endoscopy and scintigraphy for diagnosis of oro-pharyngeal dysphagia. Acta Otorhinolaryngol Ital. 2016;36(5):395–402. doi:10.14639/0392-100X-829.
- Steele CM, Alsanei WA, Ayanikalath S, et al. The Influence of Food Texture and Liquid Consistency Modification on Swallowing Physiology and Function: A Systematic Review. Dysphagia. 2015;30(2):272–273. doi:10.1007/s00455-014-9578-x.
- Langdon PC, Lee AH, Binns CW. High incidence of respiratory infections in “Nil by Mouth” tube-fed acute ischemic stroke patients. Neuroepidemiology. 2009;32(2):107–113. doi:10.1159/000177036.
- Langmore SE, Skarupski KA, Park PS, et al. Predictors of aspiration pneumonia in nursing home residents. Dysphagia. 2002;17(4):298–307. doi:10.1007/s00455-002-0072-5.
- Langmore SE, Terpenning MS, Schork A, et al. Predictors of aspiration pneumonia: how important is dysphagia? Dysphagia. 1998;13(2):69–81. doi:10.1007/PL00009559.
- Kang JH, Baik HW, Chung HK. Trace element deficiencies in long-term tube fed patients. Espen J. 2014;9(2):E63–E68.
- Umrania R, Patel D, Patel B, et al. Survey of psychosocial issues of nasogastric tube feeding in head-and-neck cancer patients. Indian J Palliat Care. 2021;27(1):113–117.
- Archer SK, Wellwood I, Smith CH, et al. Dysphagia therapy in stroke: A survey of speech and language therapists. Int J Lang Commun Disord. 2013;48(3):283–296. doi:10.1111/1460-6984.12006.
- Langmore SE, Pisegna JM. Efficacy of exercises to rehabilitate dysphagia: A critique of the literature. Int J Speech Lang Pathol. 2015;17(3):222–229. doi:10.3109/17549507.2015.1024171.
- Geeganage C, Beavan J, Ellender S, et al. Interventions for dysphagia and nutritional support in acute and subacute stroke. Cochrane Database Syst Rev. 2012;10: CD000323. doi:10.1002/14651858.CD000323.pub2.
- Krekeler BN, Vitale K, Yee J, et al. Adherence to dysphagia treatment recommendations: A conceptual model. J Speech, Lang Hear Res. 2020;63:1641–1657.
- Steele SJ, Ennis SL, Dobler CC. Treatment burden associated with the intake of thickened fluids. Breathe (Sheff). 2021;17(1):210003. doi:10.1183/20734735.0003-2021.
- Masuda H, Ueha R, Sato T, et al. Risk Factors for Aspiration Pneumonia After Receiving Liquid-Thickening Recommendations. Otolaryngol Head Neck Surg. 2022;167:125–132.
- King JM, Ligman K. Patient noncompliance with swallowing recommendations: reports from speech-language pathologists. Contemp Issues Commun Sci Disord. 2011;38:53–60.
- Herentry K. Performance-based preference for a novel xanthan gum-based thickener among clinicians treating dysphagia patients. Eur Geriatr Med. 2011;2:S24–S206.
- Schulz S, Scholz V, Lehnert B. Tasteless thickening agents? A competitive comparison. HNO. 2022;70(8):588–594. doi:10.1007/s00106-022-01161-1.
- Hibberd J. Acceptance, compliance, and tolerance of a novel xanthan gum-based thickener on oropharyngeal dysphagia patients. Dysphagia. 2011;26:432–475.
- Hadde EK, Chen J. Shear and extensional rheological characterization of thickened fluid for dysphagia management. J Food Eng. 2019;245:18–23.
- RCSLT. Position statement on the use of thickened fluids in the management of people with swallowing difficulties. 2024. https://www.rcslt.org/wp-content/uploads/2024/01/Thickened-fluids-position-paper.pdf