Transcript Document

High-Resolution Manometry &
24-hour Reflux Testing
Swallowing: One Bite At A Time
-or-
Don’t Bite Off More Than You Can Chew
Presented by
Ron Turner, CRCP, Clinical Educator
Swallowing Disorder Diagnostics
[email protected]
GuideWare™ Copyright Ron Turner, CRCP
ManoScan™ , ManoView ™ , AccuView ™ screen captures courtesy & copyright
Sierra Scientific/Given Imaging, Inc.
What is Esophageal Motility?
The Ability of Esophageal Swallowing Pressures
to Effectively Transport Swallowed Substances
from the Pharynx to the Stomach
Why We Do What We Do:
Endoscopic Photograph of Barrett’s Esophagus, the
Road to Esophageal Cancer
GI Motility online (May 2006) | doi:10.1038/gimo44
Figure 2 Anatomic radiographic landmarks of the lower esophageal sphincter
(LES).
GI Motility online (May 2006) | doi:10.1038/gimo3
Treatment of Esophageal Motility Disorders
Achalasia:
Progressive Endoscopic Dilation, Botox injection, Heller Myotomy
Weak and Ineffective Esophageal Motility (IEM):
Bethanechol (muscle contractor) and new pro-motility meds
Spasm (DES, Jackhammer Esophagus), & Hypertensive LES:
Meds
(calcium
channel
blockers,
botox,
nitrates,
tricyclic
antidepressants), progressive dilatation, esophageal wall myotomy
Scleroderma:
Anti-inflammatory and anti-fibrotic medications
Hyptotensive LES (with qualifying GERD):
Laparoscopic Fundoplication*
Choice of Half (Toupet) or Full (Nissen) Anti-Reflux Wrap
*Qualified by pre-surgical reflux testing and manometric assessment to
determine (a) the presence of hypotensive LES residual pressure with or
without hiatal hernia, and (b) the confirmation of sufficient esophageal
contraction amplitudes necessary to overcome a surgically-tightened
LES.
What is Manometry?
Manometry is the measurement of PRESSURE. Just
like blood pressure measures the force that blood
exerts on the walls of blood vessels, esophageal
manometry measures the pressures exerted by the
esophageal muscles and valves in the esophagus that
cause motility.
So, what is Esophageal Manometry?
An esophageal manometry test (or an esophageal motility test)
measures the pressures exerted by the esophageal muscles and
valves
within
the
esophagus
during
swallowing
contractions. Contractions occur as pressure waves that carry the
food or liquid from the throat to the stomach. This carriage of food is
called motility. The pressure of the esophageal muscles and valves is
the “motor” that drives motility. Esophageal manometry measures
this motor (muscle) function, and thus, motility.
The Physics of Bolus Transit
Normal esophageal bolus transit is the movement of any swallowed substance in a
proximal-to-distal squeezing (peristaltic) direction within the functional swallowing
anatomy that spans from the pharynx to the stomach. This normal peristaltic
movement is called motility, and is caused by pressure differences, or gradients,
within the esophagus. A pressure gradient is the difference in pressure between any
two given physical locations at any given point in time. Normal antegrade (forward)
esophageal bolus transit occurs when the pressure in any given location in the
esophagus exceeds the pressure that is distal to (below) that specific location.
Conversely, retrograde (backward) bolus movement occurs when the pressure in any
given location in the esophagus exceeds the pressure that is proximal to (above) that
specific location.
The Direction of Bolus Transit
In short, substances move from a location of higher pressure to a location of lower
pressure. Just like squeezing a tube of toothpaste, proximal pressures that
occlude the esophageal lumen must occur to create peristaltic movement distally.
This is what causes the either downward or upward direction in the movement of
swallowed substances within the esophagus.
The Mechanics of Bolus Transit
For complete bolus clearance to occur in the esophagus, the squeeze pressure
in the esophageal body must exceed and overcome the esophagogastric
junction pressure (EGJ) (the residual pressure in the LES plus intragastric
pressure), during any given swallow. When this occurs, this pressure gradient
causes flow from the esophagus to pass down through the EGJ and empty
into the stomach. Much like the physics of a weakened dam, when the
pressure behind the dam exceeds the barrier strength of the dam, the dam
breaks and the water flows. Conversely, when esophageal body pressure
cannot overcome EGJ pressure, antegrade flow through the LES cannot occur.
If the dam is stronger than the pressure of the water, the water stays behind
the dam. Even patients with a poor relaxing LES or a hypertensive LES will
have effective swallows as long as the esophageal body pressures are
sufficient to overcome the EGJ barrier pressure during the swallow.
Effective Bolus Transit Means
Effective Swallowing
Again, effective swallowing is a simple function of esophageal pressure
gradients between proximal and distal locations, not merely the physical
state of the LES. And although the overall EGJ barrier pressure of the LES
includes the external pressure from the physical diaphragm pressing upon
the LES, effective bolus clearance is still fundamentally accomplished when
this overall combined LES/diaphragmatic barrier pressure is overcome by
higher distal esophageal pressure. Bottom line: The effectiveness and
direction of any given swallow is primarily determined by the esophageal
and EGJ pressure gradients that exists during that swallow.
Comparing Conventional Manometry with High-Resolution Manometry
Conventional Solid-State Catheter: 4 Pressure Channels, Spaced 5 cm Apart
Conventional Esophageal Manometry:
40-minutes, 30+ swallows,
13 catheter repositionings
LES
Four sensors spaced at 5 cm intervals; the distal sensor is
positioned in the LES with 4 radial sensors evenly spaced at
90-degrees at that same level; the other three
unidirectional sensors are thus positioned in the esophagus,
spanning a non-contiguous 15 cm above the LES
Conventional Manometry Is Difficult to Standardize:
Measures 4 Pressures Only, and Cannot Measure the Flow of Swallowed Liquid
(1) The catheter has only 4 measuring sensors and must be repeatedly repositioned in an
attempt to chase the constantly moving swallowing anatomy during the 45-minute study.
(2) This sensor is supposed to be inside the lower valve, but this drop in pressure is very
often simply due to the valve moving off the sensor, but it is impossible to know for sure
because the sensors do not span the entire swallowing anatomy.
1
2
High-Resolution Impedance Manometry (HRMZ) Catheter:
36 Pressure Sensors (432 circumferential pressures) Spaced 1 cm Apart
+ 18 Impedance Channels (which display the transit of swallowed liquid)
At the Same Time, All the Time
UES
LES
HRMZ is 100% standardized
because the circumferential
pressure-impedance catheter
simultaneously spans the
entire swallowing anatomy
from pharynx to stomach to
simultaneously
assess & calculate
uninterrupted 360-degree
circumferential
motor function & bolus
transit of the entire
swallowing anatomy. The
catheter NEVER has to be
repositioned because it
captures ALL real-time
anatomical movement of the
UES, esophagus, and LES.
What is High-Resolution
Pressure/Impedance Manometry?
The Combined Visualization and Measurement of the
Real-Time Pressures (Muscle Function) & Resulting
Transport of Swallowed Liquids (Bolus Transit)
of the Entire Swallowing Anatomy,
from Pharynx to Stomach
It is literally
THE LIVING ESOPHAGUS™
displayed as a real-time, full-color movie,
using blue-to-red (cold-to-hot) color to identify pressure
and magenta color to identify bolus presence and transit
The Basics of High-Resolution Manometry:
Hot in Daytona Beach, Cold in Tampa
Hot=
High Pressure
Hot
Cold
Cold=
Low Pressure
The Key to High-Resolution Manometry (HRM) is PATTERN RECOGNITION:
The average esophagus is 18-22 cm long. The HRM catheter (1) spans the entire swallowing anatomy,
from pharynx to stomach, with 36 cm of uninterrupted circumferential measurement.
As the anatomy tightens and loosens its grip on the catheter during swallowing, these low-to-high
pressure changes are reflected as cool-to-hot color changes.
Pharynx
UES
Esophagus
LES
Stomach
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