Parameters:
(1) congenital cardiac defects
(2) renal failure
(3) initial PaO2 in mm Hg
(4) initial PaCO2 in mm Hg
|
Parameter
|
Finding
|
Points
|
|
congenital cardiac defects
|
absent
|
0
|
|
|
present
|
1
|
|
renal failure
|
absent
|
0
|
|
|
present
|
1
|
|
initial PaO2
|
< 40 mm Hg
|
1
|
|
|
>= 40 mm Hg
|
0
|
|
initial PaCO2
|
<= 50 mm Hg
|
0
|
|
|
> 50 mm Hg
|
1
|
where:
• Cardiac defects were not specified and probably indicate significant anomalies.
• The timing of the initial blood gases is unclear. It appears that these were the first ones taken after admission to the neonatal ICU and following placement of an arterial line in the radial artery.
• According to page 822 the mortality increases 1% for each increase in the PaCO2 above 50 mm Hg and for each decrease in PaO2 below 40 mm Hg. The use of a single point at the cutoffs is simple but may overestimate risk near the cutoff and underestimate risk for values away from the cutoffs.
total number of risk factors =
= SUM(points for all 4 parameters)
Interpretation:
• minimum risk score: 0
• maximum risk score: 4
• The higher the risk score the lower the survival.
• Timing of surgery (early vs late if before or after 48 hours after delivery) did not influence survival. Therefore optimizing the patient's preoperative condition should be the management goal.
