BMP Flashcards Preview

Lab Medicine > BMP > Flashcards

Flashcards in BMP Deck (70)
Loading flashcards...
1

When do you order a BMP?

- Hospital Admission
- Fluid Status in Doubt
- Pt on a medication that effects electrolytes (i.e. diuretics)

2

Components of the BMP

- Na+
- K+
- Cl-
- HCO3-
- BUN
- Cr
- Ca2+
- Glucose

3

This is the most common electrolyte disorder counting for 5% of hospitalized elderly patients.

Hyponatremia

4

Common Cause of Hyponatremia

Excess Fluid Build Up

5

Symptoms of Hyponatremia

- Headache
- Lethargy
- Confusion
- Seizure

Depends on the rapidity of onset

6

Classification of Hyponatremia

1. Calculate Serum Osmolality
2. Measure Urine Osmolality to eliminate pyschogenic polydipsia
3. Assessment of ECF Volume

7

How do you calculate serum osmolality?

Osmolality = 2(Na+) + (Glucose/18) + (BUN/2.8)

8

Normal Range of Serum Osmolality of Sodium

285-295

9

What is the most common type of Hyponatremia?

Low Osmolality Hyponatremia

10

What are the causes of hyponatremia with high extracellular volume?

- Heart Failure
- Renal Failure
- Liver Failure/Cirrhosis

11

What are the causes of hyponatremia with normal extracellular volume?

- SIADH
- Hypothyroidism
- Adrenal Insufficiency

12

What are the causes of hyponatremia with low extracellular volume?

- Vomiting
- Renal Sodium Wasting (Intrinsic vs. Extrinsic/Diuretics)

13

Goals of Therapy for Hyponatremic Patient

1. Restrict H2O intake or Promote H2O loss

2. Replace Sodium if needed (rare)

3. Correct the underlying cause

14

How is Hyponatremia Treated?

Passively

- For heart, kidney, liver failure, the hyponatremia is usually mild and fluid restriction of approx. 1200 cc of fluid per day is all that is needed.

- Diuretics can be used with caution for faster response or if fluid restriction can't be adhered to.

15

How is Severe Hyponatremia Treated?

Actively

- Coma: Sz related to Hyponatremia
- Can give Saline to Correct
- Need to remember not to correct too quickly
- Rate of correction should be 0.5 mmol per hour (no more than 12 mmol in a day)

16

What is the condition precipitated by correcting hyponatremia too quickly?

Central Pontine Myelinolysis

*Manifests by confusion, paralysis, CN deficits (Locked-In Syndrome)

17

Condition where there is excess Anti-Diuretic Hormone causing Hyponatremia

SIADH

Syndrome of Inappropriate Anti-Diuretic Hormone Release

18

Function of ADH

Promotes Water Retention in the Renal Tubules

19

Hyponatremia is defined by what level of Sodium?

< 135

20

Hypernatremia is defined by what level of Sodium?

> 145

21

Cause of Hypernatremia

- Not enough water in
OR
- Too much water out

*Extremely rare to raise sodium by giving too much sodium

22

Causes of "Not Enough Water In" Based Hypernatremia

Impaired Thirst

- Can be caused by Tumor or Stroke in Hypothalamus (Osmolality Center)
- No access to water (Common)

23

Causes of "Too Much Water Out" Based Hypernatremia

- Dehydration from Heat, Burns, Diarrhea
- Renal Water Loss from Diabetes Insipidus
- Essentially the opposite of SIADH
- Water not absorbed in distal tubule and is wasted in excess sodium

24

Symptoms of Hypernatremia

- Thirst
- Hypotension
- Muscle Weakness, Irritability
- Confusion
- Coma, Sz

25

Total Body Water Per Body Weight in Men?

In Women?

60% of Weight Men

50% of Weight Women

26

What is the treatment of Hypernatremia?

Calculate a Water Deficit and Replace over 24 Hours

27

How do you Calculate Water Deficit in Men?

WD = [(Plasma Na+ - 140) x TBW] / 140

28

This is primarily an intracellular cation and can increase when there is lysis of the cells.

Potassium

29

Normal Range for Potassium

3.5-5.2 mEq/L

30

T/F: Potassium Levels 3.5 to 2.0 are usually well tolerated.

False.

K+ Levels 3.5-3.0 are usually well tolerated