Duan et al developed the HACOR score for evaluating a hypoxic patient placed on noninvasive ventilation. This can help to identify a patient failing this form of respiratory support. The authors are from the First Affiliated Hospital of Chongqing Medical University in China.
Patient selection: hypoxic patient
Outcome: NIV failure (resulting in need for intubation)
Parameters:
(1) heart rate (H), in beats per minute
(2) acidosis (A), based on arterial pH
(3) conciousness (C), based on the Glasgow Coma Score (GCS)
(4) oxygenation (O), based on the PaO2 to FIO2 ratio
(5) respiratory rate (R), in breaths per minute
|
Parameter
|
Finding
|
Points
|
|
heart rate
|
<= 120 beats per minute
|
0
|
|
|
> 120 beats per minute
|
1
|
|
pH
|
>= 7.35
|
0
|
|
|
7.30 to 7.34
|
2
|
|
|
7.25 to 7.29
|
3
|
|
|
< 7.25
|
4
|
|
Glasgow Coma Score
|
15
|
0
|
|
|
13 or 14
|
2
|
|
|
11 or 12
|
5
|
|
|
3 to 10
|
10
|
|
PaO2 to FIO2 ratio
|
>= 201
|
0
|
|
|
176 to 200
|
2
|
|
|
151 to 175
|
3
|
|
|
126 to 150
|
4
|
|
|
101 to 125
|
5
|
|
|
<= 100
|
6
|
|
respiratory rate
|
<= 30 breaths per minute
|
0
|
|
|
31 to 35
|
1
|
|
|
36 to 40
|
2
|
|
|
41 to 45
|
3
|
|
|
>= 46
|
4
|
total score =
= SUM(points for all 5 parameters)
Interpretation:
• minimum score: 0
• maximum score: 25
• The higher the score the greater the risk of NIV ventilation failure.
• The score performed at 1, 12, 24 and 48 hours after starting NIV correlated with failure.
|
Score at 1 Hour
|
NIV Failure
|
|
0 or 1
|
8%
|
|
2 or 3
|
17%
|
|
4 or 5
|
32%
|
|
6 or 7
|
74%
|
|
8 or 9
|
91%
|
|
10 or 11
|
96%
|
|
12 to 25
|
100%
|
Performance:
• A score > 5 at 1 hour after starting NIV was 82-86% accurate for NIV failure.
• The area under the ROC curve for the score at 1 hour was 0.88 to 0.91.
