Calligaro et al identified a number of factors associated with pulmonary complications following elective surgery on the abdominal aorta. These can help to decide if surgery should be deferred because of excessive risk to the patient. The authors are from the University of Pennsylvania.
Examples of elective surgeries on the abdominal aorta:
(1) small aortic aneurysms
(2) aortoiliac occlusive disease (AIOD)
Pulmonary complications include:
(1) pneumonia
(2) prolonged intubation following surgery
(3) reintubation for pulmonary insufficiency
(4) respiratory failure with death
Parameters:
(1) ASA class
(2) age in years
(3) body weight
(4) forced vital capacity (FVC) as percent of predicted
(5) forced midexpiratory flow rate (FEF 25-75%) as percent of predicted
(6) volume of crystalloid replacement
(7) total operative time
|
Parameter
|
Finding
|
Points
|
|
ASA class
|
1, 2 or 3
|
0
|
|
|
4
|
1
|
|
age in years
|
<= 70 years
|
0
|
|
|
> 70 years
|
1
|
|
body weight
|
<= 1.5 times ideal body weight
|
0
|
|
|
> 1.5 times ideal body weight
|
1
|
|
FVC
|
> 80% of predicted
|
0
|
|
|
<= 80% of predicted
|
1
|
|
FEF 25-75%
|
> 60% of predicted
|
0
|
|
|
<= 60% of predicted
|
1
|
|
volume of crystalloid replacement
|
<= 6 liters
|
0
|
|
|
> 6 liters
|
1
|
|
total operative time
|
<= 5 hours
|
0
|
|
|
> 5 hours
|
1
|
where:
• Elective surgery would not be considered for a patient with an ASA class V.
• A patient with ASA class III would be expected to be at greater risk for complications.
total risk score =
= SUM(points for all 7 parameters)
Interpretation:
• minimum number of risk factors: 0
• maximum number of risk factors: 7
• The risk of pulmonary complications increases with the number of risk factors.
• A patient with pre-existing pulmonary disease would be expected to be at greater risk. This would be reflected in the FVC and FEF 25-75%.
