What must the systolic blood pressure be valued at for adequate mean arterial pressure if the diastolic pressure is 75? (Assume resting conditions)
A. at least 90
B. at least 95
C. at least 100
D. at least 105
E. at least 110
F. at least 115
G. at least 120
To calculate the mean arterial pressure (MAP), we need to know both the systolic blood pressure (SBP) and the diastolic blood pressure (DBP). The formula to calculate MAP is:
MAP = DBP + 1/3(SBP - DBP)
Given that the diastolic pressure (DBP) is 75, we can plug in the values and solve for the minimum systolic pressure required for an adequate MAP.
MAP = 75 + 1/3(SBP - 75)
Now, let's evaluate the options:
A. at least 90
B. at least 95
C. at least 100
D. at least 105
E. at least 110
F. at least 115
G. at least 120
Starting with option A:
MAP = 75 + 1/3(90 - 75) = 75 + 1/3(15) = 75 + 5 = 80
Since MAP needs to be at least 80, option A is not correct. We need to check the remaining options.
Analyzing the remaining options in a similar way, we find:
Option B:
MAP = 75 + 1/3(95 - 75) = 75 + 1/3(20) = 75 + 20/3 = 75 + 6.67 = 81.67
Option C:
MAP = 75 + 1/3(100 - 75) = 75 + 1/3(25) = 75 + 25/3 = 75 + 8.33 = 83.33
Option D:
MAP = 75 + 1/3(105 - 75) = 75 + 1/3(30) = 75 + 30/3 = 75 + 10 = 85
Option E:
MAP = 75 + 1/3(110 - 75) = 75 + 1/3(35) = 75 + 35/3 = 75 + 11.67 = 86.67
Option F:
MAP = 75 + 1/3(115 - 75) = 75 + 1/3(40) = 75 + 40/3 = 75 + 13.33 = 88.33
Option G:
MAP = 75 + 1/3(120 - 75) = 75 + 1/3(45) = 75 + 45/3 = 75 + 15 = 90
From the calculations, we can determine that the minimum systolic pressure needed for an adequate mean arterial pressure (MAP) is at least 105. Therefore, the correct answer is option D.