Hand Surgery Source

Capillary Refill

Test, Exam and Signs

Historical Overview

Historically, physicians have used manual capillary refill measurements to help diagnose moderate to severe illnesses. In the future, these manual measurements may be aided by digital videography and modified oxygen saturation probes.1

Description

  • The capillary refill test, also called the nail blanch test, measures changes in peripheral perfusion.1 Delayed capillary refill shows insufficient perfusion.2  
  • There is limited information on the capillary refill test; therefore its success depends mainly on the skill and experience of the physician.

Pathophysiology

  • The capillary refill test can help to diagnose Colles’ fracture, scaphoid fractures, paronychia finger, felon finger, distal radius growth plate fracture, and compartment syndrome.1
  • Colles’ fracture and scaphoid fractures may be caused by a fall on the outstretched hand (FOOSH).2

Instructions

  1. Obtain an accurate and complete patient history. Ask the patient to rate on a scale from 1-10 how much pain s/he usually experiences in the affected hand and/or wrist.
  2. Remove nail polish if necessary.
  3. Apply light pressure to the fingernail.
  4. Measure the time it takes for color to return to the fingernail.
  5. Examine a finger of the contralateral hand.

Variations

  • To evaluate adequate capillary refill, move the tip of a pen across the digital pulp.2

Related Signs and Tests

  • Fracture crepitus
  • Allen test2
  • Neurovascular exam
  • Cold stress test
  • Radiographs
  • Magnetic resonance imaging (MRI)

Diagnostic Performance Characteristics

  • If the capillary refill test is positive, this does not rule out arterial injury.3
  • If a felon finger is suspected, use radiographs and/or MRI to improve the reliability of the diagnosis.
Presentation Photos and Related Diagrams
  • To Assess capillary refill first compress the nail bed,
    To Assess capillary refill first compress the nail bed,
  • slide your finger distally on the fingernail while maintaining the pressure
    slide your finger distally on the fingernail while maintaining the pressure
  • and then remove the pressure and observe how briskly the blood returns under the nail.
    and then remove the pressure and observe how briskly the blood returns under the nail.
Definition of Positive Result

Capillary refill or the return of "pink" in the nail bed ooccurs within 2-3 seconds for normal skin perfusion.

Definition of Negative Result

Capillary refill or the return of "pink" in the nail bed is delayed greater than 3 seconds for poor skin perfusion.

Comments and Pearls
  • Should not be used as an isolated indicator of tisue perfussion but used as part of a complete vascular examination.
  • Capillary refill can also help assess tissue hydration
  • An injured extremity should always be compared to the uninjured extremity
  • Capillary refill is also called the nail blanch test
  • Remove nail polish before assessing capillary refill
Diagnoses Associated with Tests, Exams and Signs
Video
Capillary refill assessment
References

Cited References:

  1. Pickard A, Karlen W, Ansermino JM. Capillary refill time: is it still a useful clinical sign? Anesth Analg 2011:113(1):120-3. PMID: 21519051
  2. Culp R, Jacoby S. Musculoskeletal Examination of the Elbow, Wrist and Hand: Making the Complex Simple. New Jersey: SLACK Incorporated, 2012
  3. Rayan G, Akelman E. The Hand: Anatomy, Examination and Diagnosis. Philadelphia: Lippincott Williams & Wilkins, 2012
  4. Crook J, Taylor RM. The agreement of fingertip and sternum capillary refill time in children. Arch Dis Child 2013;98(4):265-8. PMID: 23396679
  5. Pandey, A., & John, B. M. (2013). Capillary refill time. Is it time to fill the gaps?Medical Journal, Armed Forces India, 69(1), 97–98. doi:10.1016/j.mjafi.2012.09.005