Sonographers should follow a standard exam protocol for each upper extremity examination. A complete examination includes bilateral non-invasive physiologic studies (segmental pressures, bidirectional Doppler waveforms, and/or segmental volume plethysmography) of 3 or more levels. A limited bilateral noninvasive physiologic study (segmental pressures, bi-directional Doppler waveforms, and/or segmental volume plethysmography) consist of 1-2 levels.

Throughout each examination, the sonographer should:

• Assess and monitor the patient’s physical and mental status, allowing modifications to theprocedure plan according to the patient’s clinical status
• Analyze segmental pressure and waveform findings to ensure that sufficient data is provided to the physician to direct patient management and render a final diagnosis
• Analyze sonographic findings to ensure that sufficient data is provided to the physician to direct patient management and render a final diagnosis

Continuous wave (CW) Doppler signals:

• At least three representative CW Doppler waveforms are recorded from the brachial, radial and ulnar arteries, atan angle which optimizes the visual and audible signal.
  • When waveforms from the brachial level are abnormal, Doppler waveforms from the subclavian and axillary artery are recommended.
• Gain settings are optimized to display waveform characteristics
• Audio interpretation of the CW Doppler signals should attempt to classify the signals as triphasic, biphasic (unidirectional or bidirectional), or monophasic.

Pulse Volume Recordings (PVR):

• Blood pressure cuffs are placed at the mid portion of the arm and forearm and standardized inflation pressure is used in all pulse volume cuffs.
• Three representative waveforms are obtained at both levels
• Gain settings are optimized for appropriate amplitude

Segmental Pressures:

• Blood pressure cuffs are placed at the mid portion of the arm, wrist and/or forearm.
• CW Doppler is used to obtain segmental pressures at each level using the brachial, radial, and ulnar arteries respectively.
• A wrist brachial index (WBI) is calculated by dividing the highest wrist pressure from each limb by the highest brachial pressure.

Digit waveforms and pressures:

Additional information may be obtained to differentiate between large and small vessel disease.

• Digit waveforms and pressures are obtained using photoplethysmography sensors (PPG) and digit cuffs. PPG sensor is placed on the pad of each finger being evaluated.
• At least three representative waveforms should be obtained.
• Gain settings and chart speed should be optimized.
• Additional digit pressures and waveforms may be obtained based on patient’s clinical presentation or per laboratory specific protocol.

Thoracic Outlet Test Method:

• The examination can be performed using CW Doppler tracings from the radial or ulnar arteries, PVR of the arms, or a PPG sensor attached to a finger. When symptoms include the hand or digits, evaluation of these segments may be necessary.
• A resting baseline study followed by provocative maneuvers is performed according to laboratory-specific protocol.
• The protocol may be tailored according to position-related symptoms if not covered by laboratory-specific protocol.

Cold Immersion Test:

• Examination is performed using PPG sensors or VPR (volume pulse recording)
• A baseline study is performed prior to cold immersion. PPG/VPR waveforms and digit pressures are obtained from all digits bilaterally.
  • If the baseline is abnormal, cold immersion may not be necessary. Instead, warming of the affected hands may differentiate between vasospastic disease and occlusive arterial disease.
• Sonographers should follow laboratory-specific protocol in regards to:
  • The length of time for hand immersion
  • The time intervals at which waveform tracings are obtained post-cold immersion. Post-immersion digital pressure measurements may also be obtained in addition to waveforms.
• Waveform tracings and recovery time are monitored following cold immersion.
• Monitoring should continue for a minimum of 10 minutes (or longer per laboratory-specific protocol)for recovery times longer than 5 minutes.