Capillary refill time (CRT) is defined as the time taken for color to return to an external capillary bed after pressure is applied to cause blanching.[3] It can be measured by holding a hand higher than heart-level and pressing the soft pad of a finger or fingernail until it turns white, then taking note of the time needed for the color to return once pressure is released.[4] In humans, CRT of more than three seconds indicates decreased peripheral perfusion and may indicate cardiovascular or respiratory dysfunction.[5] The most reliable and applicable site for CRT testing is the finger pulp (not at the fingernail), and the cut-off value for the normal CRT should be 3 seconds, not 2 seconds.[2]
Assessment
editIn adults
editCRT can be measured by applying pressure to the pad of a finger or toe for 5–10 seconds.[6] It became popularized in the 1980s when Champion et al. proposed a CRT of less than 2 seconds be deemed normal and included CRT in the Trauma Score.[7] The value of 2 seconds for a normal CRT that was proposed by Dr Champion had been arbitrarily chosen by his nurse, and no evidence supporting that value has subsequently been found.[8] CRT has been shown to be influenced by ambient temperature, age, sex, and the anatomical testing and lighting conditions.[9][10] The most reliable and applicable site for CRT testing is the finger pulp (not at the fingernail), and the cut-off value for the normal CRT should be 3 seconds, not 2 seconds.[2]
To assess shock, central CRT, which is done by assessing capillary refill time at the sternum, rather than finger CRT, is more useful.[6]
In infants
editIn newborn infants, capillary refill time can be measured by pressing on the sternum for five seconds with a finger or thumb, and noting the time needed for the color to return once the pressure is released (central CRT). The upper normal limit for capillary refill in newborns is 3 seconds.[11] A prolonged capillary refill time may be a sign of shock and can also indicate dehydration and may be a sign of dengue hemorrhagic fever and decreased peripheral perfusion.[12] Prolonged capillary refill time may also suggest peripheral artery disease.[4] It is generally accepted that the test is affected by many different external factors and therefore should not be relied upon as a universal diagnostic measure.[3]
In animals
editCapillary refill time is also used in veterinary medicine. An animal should have a capillary refill time of less than 1 to 1 3/4 of a second. Because animals have fur, the gums are typically used to test capillary refill time.[13]
Use
editCapillary refill time is a quick and cheap way to indicate decreased peripheral perfusion and may indicate cardiovascular or respiratory dysfunction.[5] It has also been used to assess or diagnose diseases of the peripheral circulatory system such as Raynaud's syndrome and hand–arm vibration syndrome.[6] There is disagreement as to whether the test is useful, however, and it is poorly standardised.[14][6] Poor finger or toe capillary refill time is a contraindication for the use of compressive techniques to treat peripheral oedema. Capillary refill time is traditionally used as a clinical indicator of tissue vascularity either after limb injury or after revascularization[15] and the most reliable and applicable site for CRT testing is the finger pulp (not at the fingernail), and the cut-off value for the normal CRT should be 3 seconds, not 2 seconds.[2]
In veterinary medicine, poor gum CRT may be an contraindication for use of anaesthesia, as the likelihood of anaesthesia being fatal is higher if there is an underlying heart or lung problem. Gum CRT also used to monitor health during anaesthesia.[16]
See also
editReferences
edit- ^ Doyle, Glynda Rees; McCutcheon, Jodie Anita (2015-11-23). "2.7 Focused Assessments". Clinical Procedures for Safer Patient Care.
- ^ a b c d Monteerarat, Yuwarat; Limthongthang, Roongsak; Laohaprasitiporn, Panai; Vathana, Torpon (April 2022). "Reliability of capillary refill time for evaluation of tissue perfusion in simulated vascular occluded limbs". European Journal of Trauma and Emergency Surgery. 48 (2): 1231–1237. doi:10.1007/s00068-020-01594-9. ISSN 1863-9933. PMID 33475776. S2CID 231665460.
- ^ a b King, D; Morton, R; Bevan, C (Nov 13, 2013). "How to use capillary refill time". Archives of Disease in Childhood: Education and Practice Edition. 99 (3): 111–116. doi:10.1136/archdischild-2013-305198. PMID 24227793. S2CID 12252412.
- ^ a b "Capillary nail refill test". Archived from the original on 2015-09-24. Retrieved 2014-12-21.
- ^ a b Doyle, Glynda Rees; McCutcheon, Jodie Anita (2015-11-23). "Appendix 1: Glossary". Clinical Procedures for Safer Patient Care.
- ^ a b c d Cooke, R. (2014-07-01). "The Lewis-Prusik test. Time to say goodbye to an old friend?". Occupational Medicine. 64 (5): 312–313. doi:10.1093/occmed/kqu055. ISSN 0962-7480. PMID 25005540.
- ^ Champion HR, Sacco WJ, Hannan DS, Lepper RL, Atzinger ES, Copes WS, Prall RH. Assessment of injury severity: the triage index. Crit Care Med. 1980 Apr;8(4):201-8. doi: 10.1097/00003246-198004000-00001. PMID 7357873.
- ^ Baraff LJ. Capillary refill: is it a useful clinical sign? Pediatrics. 1993 Nov;92(5):723-4. PMID 8414865.
- ^ Schriger DL, Baraff L. Defining normal capillary refill: variation with age, sex, and temperature. Ann Emerg Med. 1988;17(9):932-5.
- ^ Anderson B, Kelly AM, Kerr D, Clooney M, Jolley D. Impact of patient and environmental factors on capillary refill time in adults. Am J Emerg Med. 2008;26(1):62-5.
- ^ Krzysztof S Strozik; Clarissa H Pieper; Jacques Roller (1997-01-13). "Capillary refilling time in newborn babies: normal values". Archives of Disease in Childhood: Fetal and Neonatal Edition. 76 (3): F193–F196. doi:10.1136/fn.76.3.F193. PMC 1720653. PMID 9175951.
- ^ David C. Dugdale, III, MD (2009-05-07). "Capillary nail refill test". Retrieved 2010-11-27.
{{cite web}}: CS1 maint: multiple names: authors list (link) - ^ Stephen J. Hernandez-Divers, BVetMed (2015-03-30). "World Small Animal Veterinary Association World Congress Proceedings, 2005". VIN.com.
- ^ Pickard, Amelia; Karlen, Walter; Ansermino, J. Mark (July 2011). "Capillary refill time: is it still a useful clinical sign?". Anesthesia and Analgesia. 113 (1): 120–123. doi:10.1213/ANE.0b013e31821569f9. ISSN 1526-7598. PMID 21519051. S2CID 32622801.
- ^ Monteerarat, Yuwarat. "Is Capillary Refill Time Still A Reliable And Useful Test For Evaluating Tissue Perfusion In Injured Limb". meeting.handsurgery.org/. Retrieved June 25, 2023.
- ^ Warne, L. N.; Bauquier, S. H.; Pengelly, J.; Neck, D.; Swinney, G. (2018). "STANDARDS OF CARE Anaesthesia guidelines for dogs and cats". Australian Veterinary Journal. 96 (11): 413–427. doi:10.1111/avj.12762. hdl:11343/284701. ISSN 1751-0813. PMID 30370594. S2CID 53097101.