Neonatal Sepsis Risk Calculator

Calculator inputs

Use all clinically available details. Leave only nonessential identifiers blank. The form is arranged in responsive columns: three on large screens, two on medium screens, and one on mobile.

Patient name

Record number

Age at assessment (hours)

Gestational age (weeks)

Birth weight (g)

Rupture of membranes duration (hours)

Highest maternal intrapartum temperature (°C)

Current neonatal temperature (°C)

This tool weights temperatures below 36 or above 38.

Base deficit (mmol/L)

A value of 10 or greater adds risk weight.

Maternal GBS or current pregnancy bacteriuria/infection

Intrapartum antibiotics

Blood culture status

CRP or inflammatory marker summary

CBC or differential summary

Other local infection marker

Example data table

Scenario	Gestation	ROM	Maternal factors	Neonatal indicators	Illustrative score	Band
Stable term newborn	39 weeks	8 h	GBS negative, no fever	No symptoms, normal temperature	0	Low
Preterm exposure with symptoms	35 weeks	22 h	Maternal fever, prolonged ROM	Respiratory distress, poor feeding	7	High
Red-flag presentation	38 weeks	10 h	Chorioamnionitis	Apnoea and shock	Critical trigger	Critical

Formula used

This calculator combines a red-flag screen with a transparent weighted score. It is an educational triage aid, not a validated probability engine and not a substitute for institutional neonatal sepsis protocols.

Step 1: Red-flag rule. Any red-flag maternal context, critical neonatal indicator, or confirmed bloodstream infection moves the result to the highest concern band regardless of the subtotal.

Step 2: Weighted subtotal. Maternal and birth factors, observed neonatal indicators, and supportive laboratory abnormalities each add points. Adequate intrapartum antibiotics can reduce one point when maternal GBS risk is documented.

Step 3: Risk band. Low = 0 to 2, Moderate = 3 to 5, High = 6 to 8, Critical = red flag present or total 9 and above.

Scoring expression: Total Score = Maternal Score + Clinical Score + Laboratory Score − Protective Adjustment. Relative Index = min(100, round(Total Score ÷ 12 × 100)).

The page emphasizes guideline-aligned factors such as maternal GBS exposure, prolonged rupture of membranes, intrapartum fever, chorioamnionitis, apnoea, seizures, shock, temperature abnormality, and metabolic acidosis.

How to use this calculator

Enter gestational age, birth weight, neonatal age, rupture duration, and both temperatures.
Select maternal GBS status, intrapartum antibiotic status, and any supportive laboratory summaries available.
Tick all neonatal signs that are present at assessment, including red flags and other concerning findings.
Submit the form to generate the subtotal breakdown, risk band, and concise interpretation note.
Use the CSV or PDF buttons to save the case summary for audit, handoff, or discussion.
Always reconcile the output with cultures, serial examinations, blood gas data, and local newborn infection guidance.

Clinical notes

Neonatal sepsis can evolve quickly. A low score does not safely rule it out, especially when the newborn is preterm, clinically unstable, or showing change over time.

This page is intended for supervised clinical discussion, education, and documentation support. It should not be used by caregivers at home to delay emergency evaluation.

FAQs

1. Does this calculator diagnose neonatal sepsis?

No. It structures risk review and highlights important warning signs. Diagnosis still depends on examination, cultures, serial observations, and the treating team's protocol.

2. Is the output a validated probability percentage?

No. The result is a transparent educational score band, not a calibrated probability. It is useful for documentation and triage conversations, but not for replacing validated local tools.

3. Why are red flags handled separately?

Red flags indicate conditions that demand urgent attention regardless of any subtotal. A newborn with apnoea, seizures, shock, or confirmed infection should never be reassured by a low point count.

4. Why can intrapartum antibiotics lower the score?

Adequate intrapartum prophylaxis can reduce early group B streptococcal transmission risk. The adjustment is intentionally small because antibiotics do not remove every other infectious concern.

5. Should I enter normal lab values?

You can, but the score only changes when a supportive laboratory result is marked abnormal. Normal tests should still be interpreted alongside the clinical picture and specimen timing.

6. Can this be used for late-onset neonatal sepsis?

Not ideally. The calculator mainly reflects early-onset screening logic around birth and the first 72 hours. Late-onset cases need device exposure, nursery factors, and other pathogen risks.

7. Why is temperature weighted automatically?

Unexplained neonatal temperature below 36°C or above 38°C is a recognized concern signal. The form calculates that contribution directly from the entered temperature.

8. When should the result be escalated immediately?

Escalate immediately when a red flag is present, the baby is unstable, cultures are positive, or the overall pattern worsens. Clinical deterioration outranks any saved report or prior score.

Reference basis

NICE neonatal infection guidance and visual summary for early-onset risk factors and clinical indicators.
American Academy of Pediatrics review of major early-onset sepsis risk factors, especially preterm birth, GBS exposure, prolonged rupture of membranes, and maternal infection signs.
CDC and related systematic evidence showing maternal GBS colonisation is an important early-onset risk factor and intrapartum antibiotics reduce early group B streptococcal disease risk.