LABORATORY AND DIAGNOSTIC PROCEDURES NURSING RESPONSIBILITY

LABORATORY AND DIAGNOSTIC PROCEDURES NURSING RESPONSIBILITY

 

This is a list of some laboratory and diagnostic procedures that I have compiled through the years. I have used it for teaching when I used to work in the academe. 

Here I have summarized the correct preparation, education, and post-test care for patients undergoing diagnostic and laboratory tests in general. Please always follow your hospital protocol.

NERVOUS SYSTEM

Skull and Spinal X-ray

Lumbar Puncture

 CT Scan

 MRI

 

SKULL X-RAY

S-ize

S-hape

S-uture separation

S-ome calcification

S-hows erosion and fracture

 

SPINAL X-RAY

A-bnormal spine and dislocation

B-one degeneration

C-ompression

D-eformed curvature

E-rosion

F-racture

 

SKULL AND SPINAL X-RAY

X-clude metal items from body parts

R-eassure nursing support

A-ccurate documentation if with thick and heavy hair

Y-ou immobilize 

 

LUMBAR PUNCTURE

 Insertion of a spinal needle through the L3-L4  interspace into the lumbar subarachnoid space to obtain cerebrospinal fluid, measure CSF fluid or pressure, or instill air, dye, or medications.

 

LUMBAR PUNCTURE DIAGNOSTIC

 

Suspected meningitis

Subarachnoid hemorrhage

Hydrocephalus

Benign Intracranial hypertension

 

THERAPEUTIC

Spinal anesthesia

Chemotherapy

 

 LUMBAR PUNCTURE CONTRAINDICATIONS

S-coliosis

I-CP unidentified

C-oagulopathy

K-yphosis

 

LUMBAR PUNCTURE PRETEST

Form of informed consent

Free of urine bladder

Fetal position

 

LUMBAR PUNCTURE INTRATEST

S-hrimp or Fetal position

S-pecimens to be collected

S-terile vials- 4 or 5 (Tube 1 - chemistry Tube 2 - stat gram stain and culture (C+S), Tube 3 – cell                                      

          count, Tube 4 - for comparison, Tube 5 (optional) - virology, mycology, cytology, etc.)

S-trict asepsis

 

LUMBAR PUNCTURE POST TEST

F-lat 12-24 hrs

F-or vital signs and LOC monitoring

F-orce fluid unless contraindicated

P-uncture site for bleeding, CSF leakage

P-erform CMS assessment (Circulation, motion, sensation)

 

LUMBAR PUNCTURE COMPLICATION Spinal Headache

F-lat

F-luids

P-ain Management

      (Note: in some cases may need “blood patching” to close off the hole)

 

CT SCAN Scans the following in successive layers by a narrow beam of x-rays:

 

Angiogram of Head

Belly and Pelvic

Chest

D ’ heart

Extremities

CT SCAN PRETEST:

Assess allergies to iodine and seafoods

Be sure to obtain informed consent

Conscious sedation for claustrophobia

Do remove jewelries and hair pins

Explain hot flushed sensation and metallic taste in the mouth when dye is injected

Fluids and hydration

Give instruction to lie supine with small pillow under the head

Hold if pregnant

It takes 20 minutes

 

CT SCAN POSTTEST:

Allergic reaction check

Be sure to replace fluid

CMS (Circulation, motion, sensation)

Distal pulse check

Extremity color check

Find bleeding and hematoma

 

MRI

M-RI is nonivasive

R-eveals types of tissue, tumors and vascular abnormalities

I-s similar to CT scan

 

MRI PRETEST

M -etal objects must be removed

A-ssess for ineligibility and contraindications

G-ive instruction to lie supine with small pillow under the head

N-ormal audible humming, thumbing, grating, or knocking sounds

E-ncourage conscious sedation for claustrophobia

T-akes 45 to 60 minutes

I -nformed consent

C-ompletely enclosed in scanner

 

MRI POSTTEST

Resume normal activities

Fluids and hydration

 

MRI Ineligible to undergo MRI:

Automatic Internal Defibrillator

Cerebral Aneurysm Clip

Cochlear Implant

Hip Replacement

Knee Replacement

Non-removable dental prosthesis

Pacemaker

Prosthetic Valve Replacement

Soldiers

 GI

Hepatobiliary iminodiacetic acid (HIDA) scan is an imaging procedure used to diagnose problems of the liver, gallbladder and bile ducts

 

Before the scan:

Fast for four hours

Stop certain medications and supplements

Have a fat-rich meal six hours before

Remove metal accessories

Inform about claustrophobia

 

During the scan:

Tracer injected into arm vein

May feel pressure or cold

 

After the scan:

Flush toilet three times after urinating

Wash hands thoroughly

Avoid breastfeeding for at least 48 hours

Discard pumped breast milk

CARDIOVASCULAR SYSTEM

Electrolytes Coagulation Studies,  Erythrocyte Studies, White Blood Cell Count, Serum Enzymes and Cardiac Markers, Serum Lipids

 

ELECTROLYTES SODIUM

A –bsorbed from the small intestine and excreted in the urine in amounts dependent on

    dietary intake

S-ustains osmotic pressure and acid base balance

I-s major extracellular cation

N-ormal daily requirement is 15 mEq

SODIUM Nursing Consideration: Drawing blood samples soon after an intravenous infusion of sodium chloride will increase the level, producing an inaccurate result.

ELECTROLYTES POTASSIUM

P-romote cellular water balance, electrical conduction in muscle cells, and acid base balance O-btains K through dietary ingestion and the kidneys preserve or excrete K

T-o evaluate cardiac, renal, and gastrointestinal function

A-major intracellular cation

POTASSIUM Nursing Consideration:

A -ccurate note if the patient is receiving K supplement

B-lood should not be drawn from site where an IV infusion exists

C-lenching and unclenching of hand can increase the level

D-o identify elevated WBC and platelet counts

 

ELECTROLYTES CHLORIDE

H-ighly abundant body anion in the extracellular fluid

C-ounterbalance cations and buffer

L -ets digestion and maintenance of osmotic pressure and water balance

 

CHLORIDE Nursing Consideration:

D-raw blood from an extremity that does not have normal saline infusing into it

D -o not allow the client to clench and unclench his or her hand before drawing blood

D-iarrhea and prolong vomiting will alter chloride results

 

ELECTROLYTES MAGNESIUM

Clotting mechanism

Controls neuromuscular activity
Cofactor that modifies activity of many enzymes

Calcium metabolism

 

MAGNESIUM Nursing Consideration:

P -rolong use of magnesium products will cause increased serum levels

P -arenteral nutrition therapy or excessive loss of body fluids may decrease serum levels

 

ELECTROLYTES CALCIUM

B - one formation

C-onversion of prothrombin to thrombin

T -ransmission of nerve impulse

C-ontraction of skeletal and myocardial muscles

CALCIUM Nursing Consideration: Instruct the client to eat a diet with a normal calcium level (800 mg/day) for 3 days before the test. Instruct the client that fasting may be required for 8 hours before the test .

 

COAGULATION STUDIES

ACTIVATED PARTIAL THROMBOPLASTIN TIME (APTT)

A - mount of time it takes in seconds for recalcified plasma to clot after partial

      thromboplastin is added

P-erformed for patient receiving heparin

T -est for deficiencies and inhibitors of clotting factors

T -ime: 20 to 36 seconds

 

ACTIVATED PARTIAL THROMBOPLASTIN TIME (APTT) Nursing Consideration:

A -spirate blood sample 1 hour before next scheduled heparin dose

P-erform blood exraction from arm into which heparin is not infusing

T -ransport specimen to the laboratory immediately

T -ime: 1.5 to 2.5 times normal if on heparin therapy

 

COAGULATION STUDIES PROTHROMBIN TIME (PT) and INTERNATIONAL NORMALIZED RATIO (INR)

P -rothrombin is a vitamin K dependent glycoprotein produced by the liver for fibrin clot

                       formation

T-o monitor response to warfarin sodium (Coumadin)

 

PROTHROMBIN TIME (PT) and INTERNATIONAL NORMALIZED RATIO (INR) Normal Values: PT: 9.6 to 11.8 secs (male)

                  9.5 to 11.3 secs (female)

          INR: 2.0 to 3.0 (standard warfarin tx) 3.0 to 4.5 (high dose warfarin tx)

 

PROTHROMBIN TIME (PT) and INTERNATIONAL NORMALIZED RATIO (INR) Nursing Considerations:

A- baseline PT should be drawn before anticoagulation therapy

B-e sure to apply direct pressure to the venipuncture site

C-oncurrent warfarin therapy with heparin therapy can lengthen the PT

D -iets high in green leafy vegetables can shorten PT

E-xpect 1.5 to 2 times longer PT if on anticoagulation therapy

F-or PT greater than 30 secs, initiate bleeding precautions

 

COAGULATION STUDIES CLOTTING TIME

C -lient should not receive heparin 3 hours before specimen collection

L-onger if pt on any anticoagulation therapy

O –r has thrombocytopenia

T-ime: 8 to 15 minutes

 

COAGULATION STUDIES PLATELET COUNT

Plug formation

Clot retraction

Coagulation factor activation

 

PLATELET COUNT 150T – 400T cells/mm3

<PLT – thrombocytopenia (risk for bleeding)

>PLT – thrombocytosis (risk for clot) – prophylaxis by Anticoagulant - Lovenox

 

PLATELET COUNT Nursing Considerations:

B -leeding precautions should be instituted in clients with low platelet

M -onitor venipuncture site

C -hronic cold weather, high altitudes, and exercise increase platelet count

 

ERYTHROCYTE STUDIES ERYTHROCYTE SEDIMENTATION RATE (ESR)- 0 to 30 mm/hr

I ndirectly measures how much inflammation is in the body.

Special preparations not needed, but fatty meal may cause plasma alterations

Rate at which erythrocytes settle out of anticoagulated blood in 1 hour

 

ERYTHROCYTE STUDIES RED BLOOD CELLS

R -esults in the delivery of oxygen to the body tissues

B -lood diseases diagnosis

C-irculate for 120 days and are removed from the blood via the liver, spleen, and bone marrow

S-pecial preparation not needed

 

RED BLOOD CELLS 4.5-5.5 million/mm3

 <RBC – Anemia (Fatigue, SOB)

>RBC – Polycythemia (erythrocytosis) – management phlebotomy

 

ERYTHROCYTE STUDIES HEMOGLOBIN and HEMATOCRIT

Hemoglobin is the main component of erythrocytes and serves as the vehicle for transporting O2 and CO2

Normal Values: 14 to 16.5 g/dl (male) 12 to 15 g/dl (female)

Hematocrit represents red blood cell mass and is an important measurement in the identification of anemia or polycythemia

Normal Values: 42% to 52% (male) 35% to 47% (female)

 

WHITE BLOOD CELL COUNT

 WHITE BLOOD CELL Immune defense system of the body

WBC 5,000-10,000 cells/mm3

 <WBC – leukopenia (risk for infection)

>WBC – leukocytosis (infection/inflammation)

>100,000 – incapable of phagocytosis (leukemia)

 

CARDIAC MARKERS CREATINE KINASE (CK) Found in:

CK-MB (Cardiac)--- 0% to 5%

CK-BB (Brain)--- 0%

CK-MM (Muscles)--- 95% to 100%

 

CREATINE KINASE (CK)

Onset: 6 hours

Peak: 18 hours

Return to Normal: 2 to 3 days

 

CREATINE KINASE (CK) Nursing Considerations: CK-MM:

Avoid strenuous physical activity for 24 hours before the test

Avoid ingestion of alcohol for 24 hours before the test

Avoid invasive procedures and intramuscular injection:  may falsely elevate CK levels

 

CARDIAC MARKERS LACTASE DEHYDROGENASE (LDH)

Onset: 24 hours

Peak: 48 to 72 hours

Return to Normal: 7 to 14 days

 

LACTASE DEHYDROGENASE (LDH) Nursing Considerations: LDH isoenzyme levels should be interpreted in view of the clinical findings

Testing should be repeated on 3 consecutive days

 

CARDIAC MARKERS TROPONIN

T - and I

R-egulatory protein found in striated muscle AND

O-n bloodstream when an infarction causes damage to the myocardium

 

TROPONIN I

 >1.5 ng/ml… MI

Onset: 3 hours

Returns to Normal: 7 to 10 days

 

 TROPONIN T

 >0.1 to 0.2 ng/ml… MI

Onset: 3 hours

Returns to Normal: 7 to 14 days

 

TROPONIN Nursing Considerations: Testing is repeated  q 8 hours X 3.

 Rotate venipuncture sites.

 

CARDIAC MARKERS MYOGLOBIN Oxygen-binding protein found in striated muscle that releases oxygen at very low tensions

Injury to skeletal muscle will cause a release of myoglobin into the blood

 

MYOGLOBIN

 >90 mcg/L… MI

Onset: 1 to 2 hours

Peak: 4 to 6 hours

Return to Normal: 24 to 36 hours

           

SERUM LIPIDS

Total Cholesterol--- 140 to 199 mg/dl

 Low Density Lipoprotein (LDL)--- <130 mg/dl

High Density Lipoprotein (HDL)--- 30 to 70 mg/dl

Triglycerides--- < 200 mg/dl

SERUM LIPIDS Nursing Considerations:

No oral contraceptives

NPO except water for 12 to 14 hours

No alcohol for 24 hours

No high cholesterol foods the evening meal before the test

 

RESPIRATORY SYSTEM

Chest X-ray, Sputum Specimen, ABG Analysis, Peak Flow Meter

 

CHEST X-RAY

 A-natomy

A-ppearance

 

CHEST X-RAY PREPROCEDURE:

Remove all jewelry and other metal objects from the chest area

Assess the client’s ability to inhale and hold his or her breath

You question women regarding pregnancy or possibility of pregnancy

 

CHEST X-RAY POSTPROCEDURE: Help the client get dressed

 

SPUTUM SPECIMEN

Specimen thru expectoration

Suctioning of the trachea

Sputum amount: 15 ml

 

SPUTUM SPECIMEN PREPROCEDURE:

A-lways collect the specimen before antibiotic therapy

B-e sure that the client rinse mouth with water

C-lient to take several deep breaths and then cough deeply

 

SPUTUM SPECIMEN POSTPROCEDURE:

If a culture of sputum is prescribed, transport the specimen to the laboratory immediately

Assist the client with mouth care

 

ABG ANALYSIS Measurement Oxygen Carbon dioxide Arterial blood Acid base state

 

ABG ANALYSIS PREPROCEDURE:

A- llen’s test before drawing radial artery specimens

B-efore specimen collection, client to rest for 30 minutes

G-iving suction before drawing ABG sample is avoided

 

ABG ANALYSIS POSTPROCEDURE:

Place the specimen on ice

Note the client’s temperature on the laboratory form

Note the oxygen and type of ventilation that the client is receiving on the laboratory form

 

Apply pressure to the puncture site for 5 to 10 minutes or longer if the client is taking anticoagulant therapy or has a bleeding disorder

Transport the specimen to the laboratory within 15 minutes

 

ABG ANALYSIS Normal Arterial Blood Gas Values:

 pH          7.35 to 7.45

PCO2       35 to 45 mmHg

HCO3     22 to 26 mmHg

PO2        80 to 100 mmHg

O2 sat    96% to 100 %

 

ABG ANALYSIS

 R - espiratory

O - pposite

M - etabolic

E - qual

 

PEAK FLOW METER determines the effectivity of bronchodilator for asthmatic patients

PEAK FLOW METER Management:

1.Diary

2.Weeks period that the child is well

3.Blows

Results: GREEN: 80 to 100%... Very Good

             YELLOW: 50 to 80%... Beginning Attack

             RED: <50%... Bring to ER