Q6 from Study Guide

Here is the information I collected regarding Question #6. I also posted the same information to the Google Group, so if you got that, no need to duplicate. I also have it in a Word document, so if you would like me to send it to you as an email attachment, just email me at:
shelandlucy@hotmail.com
Also, if you have anything to add, feel free to post it! :)

Lab Values
(Taken from Mosby’s “Manual of Laboratory & Diagnostic Tests”)

BNP “Brain Natriuretic Peptide” = released when ventricular diastolic pressure rises
(p.124 in last paragraph)

Closely related to ANF “Atrial Natriuretic Factor” in function. The protein is stored primarily in the ventricular myocardium. BNP levels are elevated when ventricular hypertrophy, severe hypertension, and CHF.

ESR “Erythrocyte Sedimentation Rate” (aka SED Rate) = to detect illnesses associated with acute and chronic infection, inflammation, advanced neoplasm, and tissue necrosis or infarction.

ESR is a measurement of the rate at which the RBC’s settle in saline solution or plasma over a specific time period. It is nonspecific and therefore not a diagnostic for any particular organ disease or injury.
Values:
Male: up to 15mm/hr
Female: up to 20mm/hr

Hgb “Hemoglobin” = a measure of the total amount of Hgb in the blood
(p. 276)
This test is used as a rapid indirect measurement of the RBC count. Values are slightly decreased in the elderly
Values:
Male: 14-18 g/dl
Female: 12-16g/dl
Critical values: <5.0>20g/dl

Hct “Hematocrit” = a rapid measurement of RBC count
(p.272)
This test is an indirect measurement of RBC number and volume. Values are slightly decreased in the elderly.
Values:
Male: 42%-52%
Female: 37%-47%

PT “Pro-Time”(aka INR “International Normalized Ratio”) = evaluate extrinsic system and common pathways in the clotting mechanism
(p.395-397)
The homeostasis and coagulation system is a homeostatic balance between factors encouraging clotting and the factors encouraging clot dissolution. The first reaction of the body to active bleeding is blood vessel construction. In small vessel injury this may be enough to stop bleeding. In large vessel injury, hemostasis is required to form a clot that will durably plug the hole until healing can occur.
Values:
Normal = 11.0-12.5 seconds; 85%-100%
Full anticoagulant therapy; >1.5-2.0 times control value; 20%-30%
Critical Values = >20 seconds
Full anticoagulant therapy: three times control value
INR
DVT prophylaxis 1.5-2.0
DVT 2.0-3.0
Orthopedic surgery 2.0-3.0
A-Fib related prophylaxis 2.0-3.0
PE 3.0-4.0
Prosthetic valve propylaxis 2.5-3.5

PTT “Partial Thromboplastin Time” (aka aPTT, a = “Activated”) = like the PT, assesses the intrinsic system and common pathway of clot formation, but is primarily used when the pt is taking Heparin.
(p.350)
(see PT for explanation)
Values:
aPTT: >70 seconds
PTT: >100 seconds


Troponin = to determine if pts chest pain is due to cardiac ischemia
(p. 464)
Cardiac markers for eveidence of an ischemic attack and predicting the possibility of future cardiac events.
Values:
Cardiac Troponin T <0.2>

Electrolytes:
K+ 3.5-4.5 mEq/L
Na+ 135-145 mEq/L
Ca++ 4.5-5.5 mEq/L
Mg++ 1.5-2.5 mEq/L