The Score for Neonatal Acute Physiology (SNAP) is a illness severity measure which can be used to compare outcomes of care in different neonatal intensive care units. It scores the worst physiologic derangement in each organ system for the first 24 hours after admission to the NICU.
|
|
1 point |
3 point |
5 point |
|---|---|---|---|
|
mean blood pressure, maximum, in mm Hg |
66-80 |
81-100 |
> 100 |
|
mean blood pressure, minimum, in mm Hg |
30-35 |
20-29 |
< 20 |
|
heart rate, maximum, in beats per minute |
180-200 |
201-250 |
> 250 |
|
heart rate, minimum, in beats per minute |
80-90 |
40-79 |
< 40 |
|
respiratory rate, in breaths per minute |
60-100 |
> 100 |
|
|
temperature in °F |
95-96 |
92-94.9 |
< 92 |
|
PaO2 in mm Hg |
50-65 |
30-50 |
< 30 |
|
PaO2/FIO2, with FIO2 as a percent |
2.5-3.5 |
0.3-2.49 |
< 0.3 |
|
PaCO2 in mm Hg |
50-65 |
66-90 |
> 90 |
|
oxygenation index |
0.07-0.20 |
0.21-0.40 |
> 0.40 |
|
hematocrit, maximum, as percent |
66-70 |
> 70 |
|
|
hematocrit, minimum, as percent |
30-35 |
20-29 |
< 20 |
|
white blood cell count, per µL |
2,000 - 5,000 |
< 2,000 |
|
|
immature-to- total neutrophil ratio |
> 0.21 |
|
|
|
absolute neutrophil count (percent neutrophils * WBC) |
500-999 |
< 500 |
|
|
platelet count, per µL |
30,000 - 100,000 |
< 30,000 |
|
|
blood urea nitrogen, in mg/dL |
40-80 |
> 80 |
|
|
creatinine, in mg/dL |
1.2-2.4 |
2.5-4.0 |
> 4.0 |
|
urine output in mL per kilogram per hour |
0.5-0.9 |
0.1-0.49 |
< 0.1 |
|
indirect bilirubin in mg/dL if birthweight > 2 kg |
15-20 |
> 20 |
|
|
indirect bilirubin in mg/dL/kg if birthweight <= 2 kg |
5-10 |
> 10 |
|
|
direct bilirubin, in mg/dL |
>= 2.0 |
|
|
|
sodium, maximum, in mEq/L |
150-160 |
161-180 |
> 180 |
|
sodium, minimum, in mEq/L |
120-130 |
< 120 |
|
|
potassium, maximum, in mEq/L |
6.6-7.5 |
7.6-9.0 |
> 9.0 |
|
potassium, minimum, in mEq/L |
2.0-2.9 |
< 2.0 |
|
|
total calcium, maximum, in mg/dL |
>= 12 |
|
|
|
total calcium, minimum, in mg/dL |
5.0-6.9 |
< 5.0 |
|
|
ionized calcium, maximum, in mg/dL |
>= 1.4 |
|
|
|
ionized calcium, minimum, in mg/dL |
0.8-1.0 |
< 0.8 |
|
|
glucose, maximum, in mg/dL |
150-250 |
>= 250 |
|
|
glucose, minimum, in mg/dL |
30-40 |
< 30 |
|
|
serum bicarbonate, maximum, in mEq/L |
>= 33 |
|
|
|
serum bicarbonate, minimum, in mEq/L |
11-15 |
<= 10 |
|
|
serum pH |
7.20-7.30 |
7.10-7.19 |
< 7.10 |
|
seizures |
single |
multiple |
|
|
apnea |
responsive to stimulation |
unrespon-sive to stimulation |
complete apnea |
|
stool guiac |
positive |
|
|
where:
• mean blood pressure = ((systolic blood pressure) + (2 * (diastolic blood pressure))) / 3
• immature-to-total neutrophil ratio is the (summation of promyelocytes + myelocytes + metamyelocytes + bands-stabs) divided by (total neutrophils)
• for indirect bilirubin, only one value is entered based on body weight
• for total calcium and ionized calcium, only one value is returned for high or low (total and ionized "mutually exclusive")
• oxygenation index = ((mean airway pressure) * (FIO2) * 100) / (PaO2)
Limitations:
• The immature-to-total neutrophil ratio assumes that the findings are consequent to a left shift in neutrophilia and that there is no leukemia.
Interpretation:
• maximum score 127 (16 at 5 points, 14 at 3 points, and 5 at 1 point)
• since 9 of the parameters involve high range (total 29) and low range (total 33), and since most patients will normally meet one of these extremes, the practical maximum score is around 103 (maximum value for each parameter pair)
Specialty: Critical Care, Emergency Medicine, Pedatrics
