Preventing cardiac and vascular damage
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Preventing cardiovascular damage — VASCASSIST: The revolutionary multifunctional tool
VASCASSIST:
The ability to “read out” a patient’s pulse wave in detail puts any cardiovascular diagnostics on the inside track. Both arterial and cardiac parameters determined with the help of Model-based Pulse Wave Analysis guarantee a clear advance in knowledge compared to the often inaccurate and error-prone standard diagnostics. Working with the VASCASSIST device enables physicians to offer prevention, diagnosis, and treatment of cardiovascular diseases at an entirely new level of insight. Put to use both on time and regularly for follow-up purposes, VASCASSIST helps to effectively protect the heart and arteries with its variety of parameters and meaningful measurement data, using the globally unique Model-based Pulse Wave Analysis (mbPWA) as a differential diagnostic “allround man” tool.
The diagnostic principle relies on oscillometric blood pressure measurement employing cuffs placed on the upper arms, wrists, and ankles. Both peripheral and aortic values are determined. The algorithm-based measurement method of Model-based Pulse Wave Analysis (mbPWA) opens up a wide range of diagnostic options — including, in particular, the detection of rare cardiovascular diseases. In addition, those diseases can be localized and diagnosed much earlier than possible with conventional methods.
General notes on operation
The operation of VASCASSIST is intuitive and, therefore, easy to learn and delegate. In addition, the user guide, which requires only a few button clicks, is designed to be easily performed by medical assistants.
The operator must apply cuffs to the patient, which are connected to the device via tubes. Inflation happens entirely automatically. Depending on the selected measurement method, either two cuffs are applied to the upper arms and wrists or the upper arms and ankles. It is possible to “deselect” individual limbs at the click of a button on the VASCASSIST display and thus exclude them from a measurement, e.g., in patients with amputated or injured limbs or with vascular accesses (shunts).
The application of the cuffs
When putting on the cuffs on the upper arms, wrists, and ankles, there are a few points to keep in mind:
- Illustrations, labels, and color codes are attached or printed on the cuffs to avoid side swaps. Among other things, an “arterial man” in a pictogram still clearly indicates the correct measurement location of the cuff. Each cuff must be applied according to its marking on the right arm/wrist or the right ankle side.
- Apply the cuffs tightly, but not too tightly, analogous to a blood pressure measurement. However, a highly exact alignment of the arteries is optional because it is an oscillometric measurement method. Here, the pulse pressures are recorded over the entire cuff. Nevertheless, it is still helpful to ensure that the marking with the inscription “Artery” is located as close as possible to the corresponding arteries — ideally, the printed arrow points vertically exactly to the artery. This alignment favors a measurement under standardized conditions. Do not place the cuffs on clothing, but always on bare skin. In particular, bulky garments such as thick sweaters or jackets distort the recorded pulse pressure curves and, consequently, the measurement results.
- In this context, also ensure that garments do not cause congestion at the extremities when pushed up while putting on the cuffs.
Settings on the device before starting the measurement
Provided all cuffs are tight (but not too close!) and correctly positioned on the right sides of the body, with the arrow pointing to the artery as well as possible. The next step is to make a few critical settings on the device: Before starting a measurement, the operator has to determine the patient’s initials (ID). Since body size plays a role in the ABI calculation, this information must be set before a peripheral measurement. Furthermore, determine a pre-rest period. A rest period of about 5–10 minutes before the actual start of the measurement effectively helps to relax the patient. Letting patients rest makes the measured values more reliable and reproducible — the pre-rest period is therefore essential.
Procedure of the measurements
After selecting the desired measurement procedure by pressing a button, VASCASSIST starts with a short cuff test and then proceeds automatically to the actual measurement. During this time, the device does not require any further “supervision” from the medical assistant. Thus, if desired, it is possible to leave the room while the patient is lying relaxed while being measured from “head to toe.” Some patients often find this moment of complete rest without further observation pleasant. Not being present during measurement usually positively affects the measurement results and helps avoid the so-called “white coat effect.” This effect can occur in the presence of a physician or medical staff and lead to an undesirable measurement-falsifying excitement or nervousness.
VASCASSIST indicates the end of the measurement with a beep. Repeat the measurements for ankle-brachial index (ABI) and pulse wave velocity (PWV) several times at intervals of a few minutes, and compare the measurement results. The more the measured values of the respective individual measurements agree, the more reliable they are.
PAVD screening: the ABI measurement
First, place two cuffs on each patient’s upper arms and ankles according to the description above. Once the patient has assumed a comfortable lying position, check that the angle of inclination of the couch is at most 10%.
Assign a patient ID on the unit via the keypad, define the body height, and set the pre-rest time. Then select the “Mode” selection menu on the device by clicking the button and using the arrow keys to select “Peripheral measurement” as the measurement mode. Then start the measurement cycle by clicking on “OK.”
First, VASCASSIST automatically measures the blood pressures on the upper arm and ankle of the right side, then those on the left side of the body. All blood pressure values, pulse rates, and the calculated ABI values of the left and right halves of the body are immediately available to you on the device’s display after the measurement has ended.
Afterward, you can also have the pulse wave velocities of the left and right halves of the body determined by pressing a button while the cuffs remain. This measurement also takes only a few minutes and ends with the display of the measured values.
Tracking down cardiovascular diseases: the central measurement
You can also perform a central measurement directly after an ABI measurement. In this case, exchange the ankle cuffs for wrist cuffs; the upper arm cuffs remain. The same rules apply to the application of these cuffs in terms of alignment with the arterial markings and placement on the right side of the body. The pre-resting time is omitted if the central measurement is taken after the ABI measurement. Confirm the device’s acceptance of the same patient ID and body size and select “Central measurement” in the menu area using the arrow keys. Confirm with “OK.” VASCASSIST now measures the pulse wave velocities of the left and right halves of the body in the same way as the ABI measurement. This measurement also takes only a few minutes and ends after a signal tone with the display of the measured values.
Performing a pure central measurement without prior peripheral measurement is also possible. To do this, place a wrist cuff and an upper arm cuff on each arm, select “Central measurement” as the preset mode on display and start the measurement by pressing “OK.”
