Up Cervical Auscultation The McKaigs Stethoscopes The Swallow Current Research 

Welcome to McKaigNet.com

T. Neil McKaig MS. CCC/SLP

    The term cervical auscultation (CA) refers to the technique of auscultation or listening with a stethoscope or other amplifying device to the sounds of a bolus passes through the hypopharynx, thus cervical for the location, (the level of the 4th through the 6th cervical vertebrae) and auscultation or to listen. This technique was first suggested in the early part of the 20th century. Through the last two decades there has been a renewed interest in adding this non-invasive procedure, as an > inexpensive clinical adjunct to fluoroscopy the current standard of practice.
    However, to date the problem has been how to actually demonstrate any direct correlation between the sounds associated with swallowing with the myomechanical actions further, so as to determine whether in fact a trained clinician could identify aspiration and/or other events, which place the patient’s pulmonary system in jeopardy. If this could be demonstrated then a simple low cost clinical procedure could possibly identify patients at risk more quickly so that costs could be contained through shorter hospitalizations, more effective use of fluoroscopic and other instrumented procedure equipment.
    For the last 9 years I have been investigating this technique realizing that the only way in which this procedure could be validated and developed was to “bench mark” these sounds through simultaneously recording of they dynamic swallow using the video fluoroscopic technique and a synchronized recording of the sound. Once this was accomplished, a database of normal subjects would need to be established as a reference against which includes swallows for different ages, body mass, sexes, and different medical histories. Once there has been a sufficient number of simultaneous VFSS/A studies that can demonstrate what myomechanical actions coincide with the acoustic various acoustic signals, perhaps inferences could be made with a significant degree confidence. In pilot studies I have observed that there is a significant “normal” variation in functional swallows leading me to believe that for statistical analysis to be meaningful the samples will have to be very large and although drawn from as heterogeneous population as possible, while acquiring sufficient data of body type and personal/family medical history that homogeneous statistical inferences might be possible.
    Therefore to accomplish my goals two separate yet concurrent studies need to be embarked upon. For sake of brevity I will refer to the isolated samples for initial establishment of the acoustic database as the isolated samples study or the ISS and the capture and simultaneous capturing of Video fluoroscopic image and acoustic signal as VFSS/A. Although separate projects in and of their selves the VFSS/A will be used as iatrical part of the final dissertation to demonstrate the how the sound relates to the acoustic signal, identifying the temporal relationships of the acoustic signal developed in the ISS project to the myomechanical actions of normal swallowing.

 

The ISS:

Procedure

The proposed research project will entail the gathering of sufficient non-dysphagic (normal) individuals so as to initiate a database against which persons with swallowing disorders may be measured.  This database will include such data and be arranged so as to take into consideration the various factors and history that may lead to dysphagia subsequent to neurological insult.  Participating individuals will be given the Bedside Assessment of Swallowing Safety© including the 10-milliliter thin liquid (water) test swallow.  A current family and personal health history will be obtained for later database inquiries.  The test swallow will be analyzed and measured and these measurements included in the database.  The actual swallow will be archived for possible additional research in the future.

The swallow will be captured using a Meditron® electronic stethoscope coupled to a laptop computer and captured using the Sound Forge XP® or other comparable recording software with a sample rate of 44,100 KB at 16-bit.  These files will be matched with the individual’s initials and date of birth, and upon entry to database assigned a random number and the original record destroyed.  Medical history will be entered using the standard ICD9 coding.   

* NOTE - Procedure Change:

The inclusion of two consistencies so as to better generalize the data has been instituted.  Rather than 3 simple water swallows, the subject will be asked to swallow: 3 presentations 10 ml of water, 3 presentations 10 ml of honey consistency liquids, and 3 presentations 10 ml of puree consistency (apple sauce).  The multiple consistency trials will proceed to an n of 500 is obtained. The 3 presentations 10 water only will continue at least until the initial n of 1,000 subjects is reached.

Population:

          The target n for the initial pool will be 1,000 heterogeneous individuals between 18 and 100 years of age.  Approximately evenly distributed male/female and age grouped roughly:

18 to 29     125
30 to 39     125
40 to 49     125
50 to 59     125
60 to 69     125
70 to 79     125
80 to 89     125
90 plus      125


Goals:

  1.     Develop database of non-dysphagic (normal) swallowing sounds. 

  2.     Prepare abstract for presentation.  

  3.     Deliver paper to Acoustic Society of America in December 2001.  

  4.     Submit for publication findings in peer reviewed international journal.

 

The VFSS/A:

Procedure:

 The proposed research project will entail the gathering of sufficient non-dysphagic (normal) individuals so as to initiate a database against which persons with swallowing disorders may be measured.  This database will include such data and be arranged so as to take into consideration the various factors and history that may lead to dysphagia subsequent to neurological insult.  Participating individuals will be given the Bedside Assessment of Swallowing Safety© including the 10-milliliter thin liquid (barium) test swallow.  A current family and personal health history will be obtained for later database inquiries.  The test swallow will be analyzed and measured and these measurements included in the database.  The actual swallow will be archived for further additional research.

The swallow will be captured using a McKaig Auscultation Collar© with a specially prepared radiolucent stethoscope head and available fluoroscopic table (to be later designated) coupled to a high quality S-VHS recorder (to be later designated) and subsequently digitized using a Studio 10 plus® video capture card. 

Once digitized these images will be analyzed using the Sound Forge XP® These files will be matched with the individual’s initials and date of birth, and upon entry to database assigned a random number and the original record destroyed.  Medical history will be entered using the standard ICD9 coding. 

Individuals involved in obtaining samples will be minimally a master’s level speech language pathologist trained to follow protocol as described.

Population:

A heterogeneous group of patients who would be tested with VFSS as part of their general healthcare.  This population will be predominantly geriatric in makeup as the population with dysphagia tends to fall into this group as dysphagia most commonly occurring in progressive neurological disorders and cerebral vascular accidents which are most common in the population over 60 years of age.

Goals:

  1. Develop initial database & library of simultaneously recorded VFSS/A.  

  2. Prepare Dissertation University of Stuttgart, Stuttgart, Germany 

  3. Deliver and defend dissertation University of Stuttgart, Stuttgart, Germany  

  4. Submit for publication findings in peer reviewed international journal.

It should be noted that both of these library databases will continue to expand beyond the initial completion of data to eventually perform the function of a reference library.


I would appreciate any suggestions to enhance and improve these research proposals.
The complete protocol with data points will be posted when it is available.