CRT (Capillary Refill Time)
A physical examination assessment measuring the time in seconds it takes for blanched mucous membrane color to return, assessing peripheral perfusion and blood circulation.
💬 In Plain English
CRT stands for "Capillary Refill Time." It is a quick, painless test that every veterinary doctor and technician performs during an exam. The veterinarian gently presses their thumb against your pet’s pink gums for 1 second, briefly blanching the tissue white, and then releases. In a healthy pet with good blood circulation and blood pressure, the healthy pink color rushes back in under 2 seconds (< 2 sec). If the color takes 3 or 4 seconds to return (prolonged CRT), it indicates poor circulation, dehydration, or circulatory shock.
🔬 Clinical & Technical Depth
For Vets & TechniciansFormal Clinical Definition
Physical examination hemodynamic parameter measuring the rate of microvascular capillary bed refilling following manual digital blanching of oral mucous membranes. Normal physiologic interval is < 2.0 seconds.
Why Veterinarians Use It
Veterinarians assess CRT at intake triage to rapidly identify hypovolemic shock, dehydration, vasoconstriction, or heart failure.
Clinical Context Encountered
Checked during every physical exam and recorded on vital sign sheets (e.g., "MM: pink, CRT < 2s").
Clinical Reference Guide (Prescription / Chart Abbreviation)
How many seconds it takes for gums to turn back to healthy pink after gentle pressure.
Where You Encounter It
- Physical exam intake records
- Emergency trauma and shock triage
- Anesthesia patient monitoring logs
- •A prolonged CRT (> 2 to 3 seconds) combined with pale, white, or blue gums indicates cardiovascular shock, internal bleeding, or severe dehydration requiring emergency care.
❓ Questions to Ask Your Veterinarian
Take these actionable questions with you to your next clinic visit or appointment:
- 1What was my pet’s capillary refill time and gum color (mucous membranes)?
- 2How can I safely check my pet’s gum color at home?
Academic & Clinical References
- RECOVER Evidence-Based Veterinary CPR and Triage GuidelinesOrganization: RECOVER Initiative • Accessed: 2026-01-10https://recoverinitiative.org