Reviewed September 30, 2026 by the editorial team. Educational content; follow your facility's protocols.
What capillary refill time measures
When you press on the skin you push blood out of the small surface capillaries and the area turns pale. Once you release, blood flows back in. How fast the color returns reflects peripheral perfusion: how well the heart, blood volume and small vessels are delivering blood to the tissues.
CRT is fast, free and needs no equipment, which is why it appears in pediatric assessment, trauma triage and sepsis screening. It is a screening sign, not a diagnosis. Read it together with heart rate, blood pressure, skin temperature, mental status and urine output.
Normal capillary refill time
The 2-second rule is widely taught, but the evidence behind it is thin. In a study of 304 healthy volunteers, Schriger and Baraff found that CRT rises with age and is longer in women. Applying a 2-second limit labeled 29% of healthy older adults as abnormal.
| Group | Commonly used upper limit | Evidence note |
|---|---|---|
| Infants and children | 2 seconds | Median about 0.7-0.8 s in healthy children |
| Adult men | 2 seconds | Median about 1.0 s |
| Adult women | Up to 2.9 seconds | Proposed by Schriger and Baraff, 1988 |
| Older adults | Up to 4.5 seconds | Proposed by Schriger and Baraff, 1988 |
| General reference | Under 3 seconds | Upper limit cited by StatPearls |
Use the cut-off in your facility's protocol or early warning tool. Many pediatric and sepsis pathways treat 3 seconds or more as abnormal.
How to check capillary refill step by step
There is no single standardized technique. The steps below reflect common practice and the factors known to change the result.
- Make sure the room and the patient's hand are warm. Cold skin prolongs refill.
- Choose a site: the pad of a finger or toe, or the nail bed. The skin over the sternum can serve as a central site when the hands and feet are cold.
- Hold the limb at or slightly above the level of the heart.
- Press firmly until the skin blanches, then hold the pressure for several seconds (StatPearls describes holding for up to 10 seconds; many pediatric protocols use 5).
- Release and count the seconds until the color returns to match the surrounding skin. Counting aloud or using a watch improves accuracy.
- Document the time, the site and the conditions, for example: "CRT 2 s, right index finger, warm room".
Causes of delayed capillary refill
A refill time longer than the expected limit means blood is reaching the skin slowly. The most important causes are the ones that reduce circulating volume or cardiac output.
- Dehydration from vomiting, diarrhea or poor intake
- Hemorrhage and hypovolemic shock
- Sepsis and septic shock
- Burns with large fluid losses
- Cardiogenic shock or severe heart failure
- Peripheral arterial disease or local arterial obstruction (usually one limb only)
- Hypothermia or a cold environment
- Vasoconstricting drugs
Delayed CRT with a fast heart rate, cool mottled skin, confusion or low urine output is a warning sign of shock. Escalate per your facility's protocol.
Limitations of capillary refill
CRT is simple but noisy. Know what can mislead you before acting on a single reading.
- Ambient temperature: in one study, cool rooms produced a CRT of 2.39 s versus 0.85 s in warm conditions
- Age and sex: older adults and women have longer normal times
- Observer variation: two nurses may count different times on the same patient
- Skin pigmentation, nail polish and artificial nails make the color change harder to see
- Lighting: dim light makes blanching and refill hard to judge
- Pressure and duration are not standardized, so technique differences change the result
Capillary refill in children and sepsis screening
In children, CRT is part of the circulation assessment because blood pressure often stays normal until late in shock. A prolonged refill with tachycardia is an early clue that a child is compensating.
In adults with septic shock, CRT has been studied as a bedside target during resuscitation. Its role in any specific pathway depends on your hospital's sepsis protocol.
Scales that go with this guide
Frequently asked questions
What is a normal capillary refill time?
The commonly used limit is 2 seconds or less in children and adults. StatPearls gives an upper limit of normal under 3 seconds, and research suggests healthy older adults may take up to 4.5 seconds.
What does a capillary refill of more than 3 seconds mean?
It suggests reduced peripheral perfusion, for example from dehydration, blood loss, sepsis or shock. Check the other vital signs, warm the site and repeat, and report it if it persists.
Where should you check capillary refill?
The finger pad or nail bed is most common. The skin over the sternum is sometimes used as a central site, for example when the patient's hands and feet are cold.
Why is capillary refill longer in older adults?
Normal CRT increases with age. Schriger and Baraff measured median times of 1.5 s in older women and 1.8 s in older men and proposed 4.5 seconds as the upper limit for the elderly.
Does a cold room affect capillary refill?
Yes. Cold skin constricts the small vessels and lengthens CRT. In the same 1988 study, one minute of cold water immersion raised the median CRT from 1.3 to 2.9 seconds.
More guides and tools
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Sources: Capillary Refill Time - StatPearls, NCBI Bookshelf · Schriger DL, Baraff L. Defining normal capillary refill: variation with age, sex, and temperature. Ann Emerg Med, 1988 · What Is Capillary Refill Time? - Cleveland Clinic. Text written by our editorial team. Reviewed September 30, 2026.