Mac Definition; Age-Dependent Mac Values - Dräger Apollo Instructions For Use Manual

Monitoring

MAC definition

1 MAC is the anesthetic gas concentration in the
blood at 760 mmHg (1013 hPa), at which 50% of
patients no longer respond to a skin incision with
movement.
The integrated MAC algorithm is based on the MAC
values as indicated on the list. These values are
merely guideline values. It is the information on the
slip accompanying the anesthetic agents which is
binding.
1 MAC corresponds to:
(in 100 % O
Halothane 0.77 Vol.%
Enflurane 1.7 Vol.%
Isoflurane 1.15 Vol.%
Desflurane 6.0 Vol.%
Sevoflurane 2.1 Vol.%
N O 105 Vol.%
2
The MAC values are dependent on the age of the
patient. The values indicated in the table relate to an
age of 40 years.

Age-dependent MAC values

The MAC values used in Apollo are corrected for
age. Therefore make sure that the age of the patient
is entered correctly. Calculation follows the equation
from W.W. Mapleson (British Journal of Anaesthesia
1996, P. 179-185). The equation applies to patients
older than 1 year of age.
MAC = MAC 40 x 10
age-corrected
The formula shows the reciprocal relationship
existing between MAC and age.
Apollo automatically adjusts the MAC calculation
according to the ambient pressure.
Note:
The age "1" is used when the age is set to
"<1". Special attention is required for patients
younger than one year.
166
)
2
(-0.00269 x (age - 40))
Figure 87. Influence of Age on MAC
Influence of age on the MAC value
Age (years)
Instructions for Use Apollo SW 4.5n
Desflurane
0.2*N2O
Sevoflurane
Enflurane
Isoflurane
Halothane