Neonatal sepsis is a serious infection occurring in a newborn baby. To help identify infants at risk, healthcare professionals use a standardized tool known as a neonatal sepsis score. This scoring system provides an objective assessment of a newborn’s condition, helping to guide decisions about further testing and treatment. It systematically evaluates subtle signs and symptoms that might indicate an underlying infection, allowing for prompt medical intervention.
The Purpose of a Neonatal Sepsis Score
The primary function of a neonatal sepsis score is to enable early detection and risk stratification for infection in newborns. It offers a data-driven approach that complements a clinician’s direct observations. By quantifying specific risk factors and clinical signs, the score helps medical staff decide on the urgency of intervention, ensuring that high-risk infants receive immediate attention.
Certain circumstances prompt the use of a sepsis score. If a mother had an infection, such as Group B Streptococcus, during pregnancy or delivery, the newborn is at an increased risk. Other factors include premature birth before 37 weeks of gestation, or if the amniotic sac ruptured for an extended period before birth, more than 18 to 24 hours. These situations alert the medical team to use the sepsis score to assess the infant’s risk and standardize the assessment across different caregivers.
Components of the Neonatal Sepsis Score
Different scoring systems exist, and while the specific point values may vary, they evaluate a similar set of clinical and laboratory indicators. These systems combine observable signs with results from blood tests to generate a score that corresponds to the likelihood of sepsis.
Clinical Signs
A significant part of the score is based on the physical assessment of the baby. Clinicians look for multiple signs, including:
- Respiratory distress, which can include rapid breathing, grunting sounds, or visible pulling in of the chest muscles.
- Temperature instability, which can manifest as either a fever (higher than 38°C or 100.4°F) or an unusually low body temperature (below 36°C or 96.8°F).
- Poor perfusion, which refers to inadequate blood flow that can make the skin appear pale, mottled, or bluish (cyanosis).
- Changes in heart rate, such as an unusually fast heart rate (tachycardia) or a slow one (bradycardia).
- Neurological signs, including lethargy, where the baby is difficult to arouse, or excessive irritability.
- Feeding difficulties, like a refusal to eat or vomiting.
Laboratory Parameters
In addition to physical signs, several laboratory tests are used to assess for infection. A blood sample is taken to measure specific markers that can indicate inflammation or infection. These include:
- C-reactive protein (CRP), a substance produced by the liver in response to inflammation. A high or rising CRP level can suggest an ongoing infection.
- The complete blood count (CBC), which provides information about blood cells. A high or low white blood cell (WBC) count can be a sign of infection.
- The immature-to-total neutrophil ratio (I/T ratio), which compares young white blood cells to the total number of neutrophils. A high I/T ratio suggests the body is rapidly producing new white blood cells to fight an infection.
- Platelet counts, as low platelet levels can be associated with severe infections.
Interpreting the Score and Subsequent Actions
The final number generated by the sepsis score helps clinicians categorize an infant’s risk level and determine the appropriate course of action. A low score suggests that sepsis is unlikely, and the response is continued routine observation. This involves monitoring the baby’s vital signs and overall condition to ensure they remain stable.
A moderate or equivocal score places the infant in an intermediate-risk category. This result indicates a need for heightened surveillance. The baby will be monitored more frequently, and additional tests, such as a repeat CRP level, may be ordered. The medical team might decide to start antibiotics while awaiting further results.
A high score strongly suggests the presence of an infection and prompts immediate medical intervention. The infant will be started on empiric antibiotics without delay. A blood culture will be performed to confirm the infection and identify the causative organism, but waiting for the results, which can take 24 to 48 hours, is not safe when sepsis is highly suspected.
The Role of Clinical Judgment Beyond the Score
While the neonatal sepsis score is a useful instrument, it does not provide a definitive diagnosis on its own. It is a tool designed to support, not replace, the comprehensive assessment of a healthcare professional. Experienced neonatologists and pediatricians use the score in conjunction with their clinical judgment, informed by the mother’s medical history, delivery details, and their direct observation of the infant.
The overall clinical picture is always considered. For example, a clinician might decide to treat a baby for sepsis even with a low score if the infant appears unwell based on their experience. Conversely, a baby with a higher score might be closely observed without immediate antibiotics if there is a strong alternative explanation for their symptoms, such as a temporary breathing problem.