Indications for Arterial Blood Gas Sample
Evaluate adequacy of ventilation..CO2 and Oxygenation PaO2, Determine pts response to therapy, Monitor severity and progression of disease.
Infants have a higher sensitivity to pain, use anesthetic cream, lidocaine injection or 24% sucrose dipped pacifier and Swaddling
Brachial and Femoral Sites
Usually avoided, because both feed large distal networks. Neither has collateral circulation. Brachial pulse is hard to palpate.Injury to brachial nerve =severe complications.
Used in an emergency only, as a last resort. Too close to the femoral vein, nerve and hip joint...damage to any of these results in severe complications
Preferred site for Arterial Puncture. Good access and collateral circulation, by the ulnar artery.
Dorsalis pedis or posterior tibial artery
Considered for Arterial Puncture IF radial artery shows signs of poor collateral circulation.
an alternative site for preemy or newborns. Access generally good and in these babies, temporal branched, close to the scalp, and is larger than radial artery.
Modified Allen's Test for Foot
Foot elevated, Both arteries compressed, Foot should blanch..Release artery that WONT be punctured, Observe flush ( 5 secs) returning to nail beds and sole of foot.
Baby Arterial Blood Gas Procedure
More difficult, need more patience, time and skill. Best to have a holder. May use transilluminator to locate radial artery. 25 guage needle or preheparinzed butterly.
Arterial Blood Gas Hazords/Complications
Hematoma, Arteriospasm, Air or clotted emboli, Hemmorrhage, Arterial occulsion, vasovagal response, pains and nerve damage
Normal Allen's test blanching time
Arterial Blood Sample... Indications
Evaluate if pt is ventilating (CO2, pH, and Evaluate Oxygenation (PaO2 and SaO2), See if therapy is working, and monitor progressions of disease.
Capillary Blood Gas Sample CBG
Estimates pH, and PaCO2...but does not estimate oxygenation
Capillary Blood Gas Puncture Sites
Postlateral foot, just anterior to the heel. AVOID back of the heel (BONE), Children-palmar ends of middle or ring finger, toes, or earlobes, Avoid cyanotic sites
Capillary Blood Gas Contraindications
Peripheral vasoconstriction, Polycythemia(shorter clotting times), Hypotension
Capillary Blood Gas Equipment
Preheparinized glass capillary tube, cap, lancet(<2.5 mm), gauze, Ice, Gloves, Antiseptic, Warm and moist cloth(42-45degree), Sharps container, Labeling materials
Safest site for heel stick
Postlateral Outer edges of heel... AVOID posterior heel curvature and back of the heel must because lancet could puncture the bone.
Arterial Blood Gas Major Contraindication
Lack of collateral circulation
Capillary Blood Gas Baby postion
Capillary Blood Gas Hazards complication
Infection, Burns(from warming the skin), bone calcification, nerve damage, bruising, scarring, pain, bleeding,
Arterial Catheter Sites
Umbilical arteries(neonates), Peripheral arteries older infants and children(radial, posterior tibial or dorsalis pedis)
Guage needle used for ABG
25, or preheparinized butterfly infusion kit
Capillary Blood Gas Preperation
Apply heel warmer for 5 minutes..Put on gloves..Get lancet ready..Apply antiseptic..DRY WITH STERILE GUAZE
Capillary Blood Gas Procedure
Place lancet on outer portion of plantar surface, depth <2mm, Apply mild pressure, WIPE AWAY FIRST DROP OF BLOOD, Collect sample, Fill capillary tube..Apply pressure to incision until bleeding stops.
What to do if blood stops flowing
Try to wipe away clot with gauze or alcohol wipe. Release pressure and reaply pressure again.
Things to avoid when collecting Capillary Blood Sample
Milking and excessive scooping of blood.
What happens when you put Capillary sample on ICE?
It will increase the PaO2
Handling the sample
Add metalic mixing flea to tube. with both ends sealed, used magnet to slide mixing flea up and down capillary tube for 5 seconds. This will help to prevent clot formation. REMOVE flea before analyzing.
Angle of needle going into to the artery?
Arterial Catheter Sites
Umbilical(neonate), Radial, Posterior tibial or Dorsalis pedis
facing the child...5 and 7 oclock...need to perform cannulation early on before vessels constrict
2 Positions for umbilical artery catheter
High Position (T6-T8, Thoracic vertebrae) and Low Position (L3-L4, Lumbar vertebrae)..May remain in place for days to weeks.
2 ways to place an peripheral arterial line!
Percutaneous (through the skin), and Cut-down (small surgial stoma) CHECK COLLATERAL CIRCULATION FIRST
Peripheral artery catheter size
Neonate 22-24 and Child 20-22
Complications of arterial catheter
INFECTION(>72 hours), Clotting(need to remove), Blood loss(tranfuse if needed)
Continuos Invasive Blood Gas Monitoring
Closed Loop...Designed for pts with low blood volume..monitor in line with catheter, 1.5ml analyzed in line and blood returned back to infant. ALTERNATIVE TO ABG
Calculation of MAP
sytolic + 2(diastolic)/3
MAP is used as an indication of...
Left Ventricular Afterload....resistance left ventricle must pump against.