{"id":14719,"date":"2026-05-13T18:07:47","date_gmt":"2026-05-13T18:07:47","guid":{"rendered":"https:\/\/diamondlaw.ca\/?p=14719"},"modified":"2026-05-13T18:07:47","modified_gmt":"2026-05-13T18:07:47","slug":"what-is-the-sarnat-staging-score","status":"publish","type":"post","link":"https:\/\/diamondlaw.ca\/what-is-the-sarnat-staging-score\/","title":{"rendered":"What Is the Sarnat Staging Score?"},"content":{"rendered":"

When a baby shows signs of brain injury after a difficult birth, one of the first questions doctors try to answer is: how severe is it? The Sarnat staging score is the clinical tool most often used to answer that question. It helps neonatal teams grade the severity of hypoxic-ischemic encephalopathy (HIE), a brain injury caused by a lack of oxygen and blood flow around the time of delivery, and decide what treatment a newborn needs.<\/span><\/p>\n

Sarnat staging also matters well beyond the delivery room. The score that a baby receives in the hours after birth often becomes a key piece of evidence in birth injury and medical malpractice cases involving HIE, cerebral palsy, and other long-term outcomes.<\/span><\/p>\n

Where the Sarnat Score Comes From<\/b><\/h2>\n

The score was first published in 1976 by Drs. Harvey B. Sarnat and Margaret S. Sarnat. Their original study looked at 21 newborns who had experienced fetal distress, and described a structured way to grade the sequential changes in clinical signs and electroencephalogram (EEG) findings that followed.<\/span><\/p>\n

The original purpose was to give clinicians a consistent way to describe how a newborn’s neurological condition was evolving and to help predict outcomes. Almost five decades later, the Sarnat score is one of the most widely used bedside tools for assessing newborns with suspected HIE, and a modified version is now part of the standard criteria used to identify babies who may benefit from therapeutic hypothermia (cooling) treatment.<\/span><\/p>\n

The Three Stages of HIE<\/b><\/h2>\n

Sarnat staging classifies neonatal encephalopathy into three stages of increasing severity. The categories are based on a structured neurological examination of the baby, usually performed within the first six hours of life and repeated as the clinical picture develops.<\/span><\/p>\n

Stage 1: Mild<\/b><\/h3>\n

Babies in Stage 1 are typically hyperalert, may show exaggerated reflexes, and have increased sympathetic responses such as a fast heart rate or dilated pupils. Muscle tone is generally normal, seizures are not usually present, and the EEG is typically normal. Stage 1 features often resolve within the first 24 hours after birth, and most babies who do not progress beyond this stage have favourable neurodevelopmental outcomes.<\/span><\/p>\n

Stage 2: Moderate<\/b><\/h3>\n

Babies in Stage 2 are lethargic or obtunded \u2014 less responsive than expected \u2014 and may show low muscle tone (hypotonia), abnormal reflexes, and a flexed posture. Seizures are common in this stage. Autonomic signs tend to shift to a parasympathetic pattern, with a slower heart rate, smaller pupils, and increased secretions. The EEG is often abnormal. Stage 2 can last for several days. Outcomes vary depending on how long the moderate stage persists, the response to treatment, and the imaging findings that follow.<\/span><\/p>\n

Stage 3: Severe<\/b><\/h3>\n

Babies in Stage 3 are stuporous or comatose, with very low (flaccid) muscle tone, suppressed or absent brainstem reflexes, and depressed autonomic function. The EEG can be severely abnormal, including periodic, low-voltage, or isoelectric tracings. Severe HIE carries a high risk of death and a high risk of significant long-term neurological impairment among survivors, including cerebral palsy, seizure disorders, and cognitive disability.<\/span><\/p>\n

What the Examination Looks At<\/b><\/h2>\n

The Modified Sarnat exam in common use today evaluates six categories. A trained examiner looks at each category and scores it as normal, mild, moderate, or severe:<\/span><\/p>\n