Neurovascular Assessment · What Is It, Why It’s Performed, and More

A neurovascular assessment is a systematic test used by clinicians to assess neurovascular compromise, impaired blood flow to the extremities, and damage to the peripheral nerves. 

Clinicians would perform a neurovascular assessment any time there is suspicion of compromised blood flow or nerve damage, as neurovascular compromise can lead to permanent injury (e.g., loss of a limb or even death). Compromised blood flow can occur as a result of compartment syndrome, a painful condition that occurs when pressure in the muscle increases to dangerous levels due to internal bleeding or swelling of tissues. As a result, necessary nutrients are no longer able to reach the muscles and nerves. Compartment syndrome is most commonly due to injuries such as musculoskeletal trauma to the extremities, fracture of a bone, and crush injuries. Other situations predisposing the individual to compartment syndrome and subsequently warranting a neurovascular assessment include orthopedic injury to an extremity (e.g., a Colles fracture), orthopedic surgery, spinal surgery, plastic surgery of the extremities, or following application of restrictive dressings, such as a plaster cast. 

The 6 P’s of a neurovascular assessment are pain, poikilothermia, paresthesia, paralysis, pulselessness, and pallor. When the clinician is assessing for pain, pain should only be felt at the site of the injury. Poikilothermia is the ability to regulate one's core body temperature; generally, the affected limb or area of the body should be the same temperature as the rest of the body. If the affected area is significantly cooler, this might be a sign of compromised blood flow. Paresthesias, or the feeling of numbness and tingling, can occur after an injury or post-surgery if a nerve is damaged. Testing for paralysis, or an inability to move part or all of the body, is another component of the neurovascular assessment. This involves assessing the ability to extend and bend the foot, hands, fingers, and toes and testing for muscle strength. Pulselessness refers to the absence of the radial, dorsalis pedis, and posterior tibialis pulses, or the pulses on the wrist, top of the foot, and back of the foot, respectively. When examining the pulses to assess for pulselessness, comparisons should be made from one side of the body to the other to ensure the pulses are present with symmetrical strength on both sides. Lastly, pallor, which refers to pale skin, may be indicative of compartment syndrome. In contrast, purple or blue discoloration in the skin may indicate poor venous return of blood. 

To perform a neurovascular assessment, a clinician would initially assess the 6 Ps. They would typically ask the person to note the location and severity of pain as well as whether it radiates, or spreads from the point of injury. The pain level should be proportional to the injury; otherwise, it may raise suspicion for compartment syndrome. If the individual is sedated or unable to speak, clinicians should consider non-verbal pain cues, such as grimacing or guarding (i.e., an involuntary response to protect an area of pain). Paraesthesia can be assessed by applying light touch to the extremities or pricking the area with the end of a pen cap. The clinician can grade pulses using a 0 to 3+ point scale with 0 signifying absent pulses and a 3+ indicating strong and bounding, or forceful, pulses. If the pulse is very faint or difficult to find, a Doppler scan, which utilizes sound waves to assess blood flow, can be used. Pallor can present differently in various skin tones but can be assessed by comparing the color of the skin on both sides of the body and looking for unusually pale or purplish discoloration of the skin. To assess temperature, the back of the clinician's hands should be placed on the individual’s extremities, bilaterally. Lastly, the range of motion should be tested by asking the person to perform certain movements with their arms and legs. 

A neurovascular assessment is employed any time there is suspicion of compromised blood flow or compromised neurological function, or in cases of recent injury or trauma that increase the likelihood of developing compartment syndrome. Neurovascular assessments evaluate the 6Ps which include pain, poikilothermia, paresthesia, paralysis, pulselessness, and pallor. The assessment is performed by a clinician and involves noting the severity of pain, feeling the skin for abnormalities in temperature, assessing for discoloration of the skin, checking for a pulse, and ensuring proper range of motion.