Swallowing with a Trach and Vent in the ICU: Part Two

This content is sponsored by Passy-Muir

Clinicians often have questions about how to manage dysphagia in the ICU. This article is part two of a three-part series, providing information about best practices for patients with tracheostomy tubes and mechanical ventilation. It includes evidence-based information as well as practical suggestions to manage dysphagia in this patient population. Part one (found at https://dysphagiacafe.com/2022/08/28/swallowing-with-a-trach-and-vent-in-the-icu-part-one/) included information on the research regarding dysphagia in patients with tracheostomies and mechanical ventilation, the importance of early intervention for communication and swallowing, and suggestions to increase the involvement of speech-language pathologists (SLP) in the ICU. This article, part two, focuses on assessment considerations, and the upcoming part three article will discuss treatment options, with an emphasis on rehabilitative swallowing therapy for this patient population. 

Let’s get started with some frequently asked questions about assessment. 

Where to start with assessment?

The initial step to assessment is to conduct a thorough review of the medical record and garner information from the medical team to obtain present and past medical history. When conducting a dysphagia assessment in the ICU, Brodsky et al. (2019) described the importance of gathering information related to the following:

• Hospital course and events.
• Body system functioning such as gastrointestinal, neurologic, and pulmonary systems.
• Current medical stability, mental status, and respiratory status.
  • This includes details about mechanical ventilation modes, settings, and weaning plan.
• History of intubation including reason and duration.
• Tracheostomy details, including the reason and timing for the tracheotomy and the tracheostomy tube brand, size, and type.
• Secretion management.

The next step is often a clinical swallowing evaluation (CSE). As discussed in part one of this series, many patients with tracheostomy tubes and mechanical ventilation have dysphagia and a high risk for aspiration, therefore, benefiting from an instrumental swallowing assessment. However, starting with a CSE can yield valuable information and is often a necessary component of the comprehensive dysphagia assessment. During a CSE, the SLP may conduct patient and family interviews; make observations regarding mental, respiratory, and nutritional status; conduct an oral mechanism evaluation; check readiness for an instrumental examination; and determine which instrumental exam is most appropriate. In some cases, oral trials during the CSE are deferred or may only include ice chips after oral care. According to Pisegna et al. (2018), ice chips have several advantages. They are a small controllable amount of approximately 1 ml of melted water when using small pea-sized ice cubes. They provide information about the patient’s oral control, including the ability to execute a volitional swallow, and are relatively benign if aspirated. Since this patient population has a high prevalence of aspiration, other foods and liquids which present a greater threat to the lungs if aspirated, should typically be avoided during the CSE.

To conduct a thorough CSE, airflow to the upper airway is needed. This allows the SLP to assess voice, cough, and speech during the oral mechanism exam and to interpret signs and symptoms of aspiration such as cough and changes in vocal quality. To achieve airflow to the upper airway, the cuff must be fully deflated and, if possible, a Passy-Muir® Valve (PMV) should be placed in-line with mechanical ventilation. Cuff deflation and use of the PMV are not only beneficial for efficiency and safety of swallowing (O’Connor et al., 2019) but also may be helpful in conducting a more comprehensive CSE. Without airflow to the upper airway, the CSE will not yield sufficient information for the SLP to make interpretations and treatment recommendations. In this case, an instrumental exam should be strongly considered before making any treatment decisions. Timing of the instrumental exam is dependent on many factors such as medical stability, mental and respiratory status, and trajectory of illness. 

What about blue dye assessments?

The Modified Evan’s Blue Dye Test (MEBDT), first described in 1995, is a screening tool to detect aspiration of secretions, liquids, and food in patients with tracheostomy tubes (Thompson-Henry & Braddock, 1995). The MEBDT involves adding blue food coloring (typically FD&C Blue No.1) to foods and liquids that are administered during a clinical swallowing evaluation and monitoring tracheal secretions for evidence of blue coloring. These tests have historically been considered pass or fail. If blue material is coughed or suctioned from the tracheostomy tube, the test is considered positive for aspiration. If no blue is detected in the tracheal secretions, the test is considered negative for aspiration. 

There are several limitations with the MEBDT. First, if the test is positive, the SLP only knows the patient aspirated, but does not have information regarding when or why the aspiration occurred. Second, if the tracheostomy cuff is inflated, material that is aspirated may not be immediately visualized as it takes time to seep around the cuff into the lower airway. Third, there are numerous reports of false negatives (Brady et al., 1999; Donzelli et al., 2001; Belafsky et al., 2003), so aspiration may be missed. However, it is important to mention that more recent research has reported the MEBDT to have good specificity, thus no false positives, and sensitivity for identifying aspiration (Béchet et al., 2016; Fiorelli et al., 2016). In general, the MEBDT should not be considered a diagnostic test, but as an adjunctive screening tool to the CSE for patients with tracheostomies. 

The CSE, with or without the use of blue dye, is an important part of the swallowing evaluation for patients with tracheostomies and mechanical ventilation. However, it should not be the only assessment tool.  A Videofluoroscopic Swallowing Study (VFSS) or Flexible (Fiberoptic) Endoscopic Evaluation of Swallowing (FEES) should be strongly considered in this patient population since these exams provide more objective information about swallowing function. 

Which instrumental exam is best for this patient population?

The VFSS and FEES provide important information for the SLP to interpret swallow function and make treatment recommendations. Brady and Donzelli (2013) reviewed the standard of care for FEES and VFSS and reported that both instrumental examinations are valuable and show good diagnostic agreement for aspiration, penetration, residue, diet level, and compensatory strategy recommendations. The authors stated that both exams should be considered gold standards for evaluating swallow function. 

VFSS vs. FEES considerations include:

• Patient preference.
• Specific areas of interest or concern. 
• Contraindications for either exam.
• How soon the instrumental assessment can be completed.
• Clinical swallow evaluation results.
• Hospital personnel and resources.

Some advantages of FEES in the ICU for patients with tracheostomies and mechanical ventilation include:

• Visualization of mucosa, structures, and vocal folds. This can be particularly useful to assess for evidence of intubation trauma.
• Potential for longer duration of exam. This is beneficial, especially if assessing the patient in various conditions such as cuff inflated, cuff deflated, and in-line PMV which requires extra time. 
• Portability. Conducting a FEES in the patient’s room, rather than transporting the patient to radiology for a VFSS is often easier and less fatiguing for the patient. Additionally, the portability of FEES allows the medical staff to remain in the ICU rather than leaving the floor to accompany the patient to radiology for a VFSS. 
• Visualization of secretion management.
• May be repeated with more frequency.

Although FEES is often the preferred instrumental assessment for patients in the ICU, there are certainly instances when the VFSS is warranted (i.e., FEES is contraindicated, SLP needs to garner information about the oral stage of swallowing, scanning the esophagus, or visualizing sub-mucosal structures).  

Should the cuff be deflated and the PMV in-line during the instrumental swallowing assessment? 

The exam should be performed in the patient’s potential meal-time conditions. For instance, a patient may have an in-line PMV placed in the ICU, but that may not be the patient’s condition throughout the entire day. Therefore, the SLP often needs to assess the patient in multiple conditions –  cuff inflated, cuff deflated, and cuff deflated with in-line PMV. Since the respiratory therapist (RT) will need to be present for in-line PMV placement, RT and SLP coordination and teamwork are needed. If swallowing efficiency and safety differences are noted based on the cuff and PMV status, recommendations should reflect those findings. 

As mentioned in part one, while there may be a positive impact on swallowing for some patients with use of an in-line PMV, cuff deflation and PMV use should not be a prerequisite for dysphagia assessment. Thorough assessment and individual decision-making are essential. For more information about cuff status, use of the PMV, and timing of dysphagia assessments, please see part one in this series. 

If repeat instrumental exams are needed, should the same examination be performed?

Kelly et al. (2006) and Kelly et al. (2007) investigated whether the type of dysphagia exam (FEES or VFSS) influences perception of pharyngeal residue and the scoring of penetration and aspiration, respectively.  Patients underwent simultaneous FEES and VFSS and independent raters interpreted the exams. The authors reported that residue and the Penetration Aspiration Scale scores were significantly higher when rating FEES than VFSS. The authors summarized that using instrumental exams interchangeably may misrepresent a patient’s swallowing function as improving or worsening when changes may in fact be attributable to using a different examination. This research was not specific to patients with tracheostomies and mechanical ventilation; however, these findings should be considered for all patient populations when making instrumental exam selections.

Summary

Whenever possible, dysphagia assessment should begin in the ICU. Although a CSE followed by a FEES is often ideal, there is not a cookie-cutter approach to dysphagia assessment for patients with tracheostomies and mechanical ventilation. Critical thinking, individual patient decisions, and teamwork are needed to adequately assess swallowing function in the ICU. 

References:

Brady, S., & Donzelli, J. (2013). The modified barium swallow and the functional endoscopic evaluation of swallowing. Otolaryngologic Clinics of North America, 46(6), 1009–1022. https://doi.org/10.1016/j.otc.2013.08.001

Brady, S. L., Hildner, C. D., & Hutchins, B. F. (1999). Simultaneous videofluoroscopic swallow study and modified Evans blue dye procedure: An evaluation of blue dye visualization in cases of known aspiration. Dysphagia, 14(3), 146–149. https://doi.org/10.1007/PL00009596

Béchet, S., Hill, F., Gilheaney, Ó., & Walshe, M. (2016). Diagnostic accuracy of the Modified Evan’s Blue Dye Test in detecting aspiration in patients with tracheostomy: A systematic review of the evidence. Dysphagia, 31(6), 721–729. https://doi.org/10.1007/s00455-016-9737-3

Belafsky, P. C., Blumenfeld, L., LePage, A., & Nahrstedt, K. (2003). The accuracy of the modified Evan’s blue dye test in predicting aspiration. The Laryngoscope, 113(11), 1969–1972. https://doi.org/10.1097/00005537-200311000-00021

Brodsky, M. B., Mayfield, E. B., & Gross, R. D. (2019). Clinical decision making in the ICU: Dysphagia screening, assessment, and treatment. Seminars in Speech and Language, 40(3), 170–187. https://doi.org/10.1055/s-0039-1688980

Donzelli, J., Brady, S., Wesling, M., & Craney, M. (2001). Simultaneous modified Evans blue dye procedure and video nasal endoscopic evaluation of the swallow. The Laryngoscope, 111(10), 1746–1750. https://doi.org/10.1097/00005537-200110000-00015

Fiorelli, A., Ferraro, F., Nagar, F., Fusco, P., Mazzone, S., Costa, G., Di Natale, D., Serra, N., & Santini, M. (2017). A New Modified Evans Blue Dye Test as screening test for aspiration in tracheostomized patients. Journal of Cardiothoracic and Vascular Anesthesia, 31(2), 441–445. https://doi.org/10.1053/j.jvca.2016.07.031

Kelly, A. M., Leslie, P., Beale, T., Payten, C., & Drinnan, M. J. (2006). Fibreoptic endoscopic evaluation of swallowing and videofluoroscopy: does examination type influence perception of pharyngeal residue severity?. Clinical Otolaryngology, 31(5), 425–432. https://doi.org/10.1111/j.1749-4486.2006.01292.x

Kelly, A. M., Drinnan, M. J., & Leslie, P. (2007). Assessing penetration and aspiration: how do videofluoroscopy and fiberoptic endoscopic evaluation of swallowing compare? The Laryngoscope, 117(10), 1723–1727. https://doi.org/10.1097/MLG.0b013e318123ee6a

O’Connor, L., Morris, N., Paratz, J. (2019). Physiological and clinical outcomes associated with use of one-way speaking valves on tracheostomised patients: A systematic review. Heart and Lung, 8(4), 356-364. https://doi:10.1016/j.hrtlng.2018.11.006

Pisegna, J. M., & Langmore, S. E. (2018). The Ice Chip Protocol: A description of the protocol and case reports. Perspectives of the ASHA Special Interest Groups, 3(13).

Thompson-Henry, S., Braddock, B. (1995). The modified Evan’s blue dye procedure fails to detect aspiration in the tracheostomized patient: Five case reports. Dysphagia, 10, 172–174. https://doi.org/10.1007/BF00260973