Transcript File
pH
7.35 to 7.45
PaCO2
35 to 45 mm Hg
HCO3ˉ
19 to 25 mEq/L
PaO2
80 to 100 mm Hg
Oxygen
Base
saturation >90-95%
excess/deficit
±5mEq/L
Normal
plasma pH is 7.35 to 7.45
PH is an indicator for H+ concentration.
Homeostatic mechanisms consist of : buffer system, the
kidney, and the lung
Major extracellular fluid buffer system; bicarbonatecarbonic acid buffer system
Kidneys regulate bicarbonate in ECF
Lungs
under the control of the medulla regulate CO2 and,
therefore, carbonic acid in ECF
Other
buffer systems
ECF:
ICF:
inorganic phosphates and plasma proteins
proteins, organic and inorganic phosphates
Hemoglobin
Low
pH <7.35
Low bicarbonate <22 mEq/L
Most commonly due to early renal failure, diarrhea and
diuretic use (Diamox and K- Sparing )
Manifestations:
headache, confusion, drowsiness, increased
respiratory rate and depth, decreased blood pressure,
decreased cardiac output (when PH<7), dysrhythmias,
shock; if decrease is slow, patient may be asymptomatic
until bicarbonate is 15 mEq/L or less, cold skin
Diagnostic
Finding:
• ABG’s ( PH<7.35, HCO3 <22mEq\L) cardinal feature.
• Increase K
• Hyperventilation (decrease Paco2)
• ECG ( flat P wave and peaked T wave)
Medical Management:
- Correct the underlying problem.
- Administer bicarbonate if PH<7.1 and HCO3 < 10mEq\L
- Monitor S.K level
- Dialysis
- Serum calcium levels may be low with chronic metabolic
acidosis and must be corrected before treating the acidosis
High
pH >7.45
High
bicarbonate >26 mEq/L
Causes:
due to vomiting or gastric suction (common cause);
pyloric stenosis, may also be caused by medications
(especially long-term diuretic use as loop diuretic and
thiazide), administration of NaHco3 in CPR), causes of
hypokalemia, hyperaldostronism
Clinical
manifestation: symptoms related to decreased
calcium (tingling, hypertonic muscle), respiratory
depression, tachycardia, and symptoms of hypokalemia,
decrease intestinal motility
Diagnostic
finding:
- ABG’s (PH>7.45, HCO3 >26mEq\L)
-
Paco2 increase (hypoventilation)
-
Decrease S.K level
Medical
Management:
Correct underlying disorder, supply chloride to allow
excretion of excess bicarbonate, and restore fluid volume
with sodium chloride solutions, I&O, KCl, H2receptors
antagonist (cimetidine)
Low
pH <7.35
PaCO2 >42 mm Hg
Always due to a respiratory problem with
inadequate excretion of CO2 and inadequate
ventilation.
Other causes: PE, atelectasis, MG,
pneumothorax, aspiration of foreign object,
pneumonia.
C\M: increase (P,RR, BP), mental cloudiness,
increase ICP, hyperkalemia, feeling of fullness
in the head
Diagnostic
-
Finding:
ABG’s ( PH< 7.35, PaCo2 >42mmHg )
S.electrolyte level
Chest X-ray.
Medical
Management: Treatment is aimed at
improving ventilation, adequate hydration, place pt in
semi fowler position
High
pH >7.45
PaCO2
<38 mm Hg
Always
due to hyperventilation
Other
causes: anxiety, hypoxemia, inappropriate
ventilator setting
C\M:
lightheadedness, inability to concentrate,
numbness and tingling, and sometimes loss of
consciousness, tachycardia.
Medical
management:
- Treat the underlying cause.
- Instruct pt to breath more slowly
into close system if the cause is
anxiety.
A normal
PH in the presence of changes in Paco2 and
Hco3 concentration
Respiratory
acidosis and respiratory alkalosis is the only
mixed disorder can’t occur at the same time
Mr. x admitted to the hospital His ABG’s as
follows (PH = 7.5, HCO3ˉ = 30, PaCo2= 40)
what is your interpretation?
Metabolic Alkalosis
Mr. Y admitted to the hospital His ABG’s as
follows (PH = 7.2, HCO3ˉ = 13, PaCo2= 50)
what is your interpretation?
Metabolic & Respiratory Acidosis.
Purpose:
-
Provide water, electrolyte, and nutrients to
meet body requirements
Replace water and correct electrolyte deficit
Administer medication
Types
-
of IVF:
Isotonic
Hypotonic
hypertonic
Total
osmolality close to that of ECF
Do not affect cell
Expand ECF volume
(1L expand the ECF by 1L, and expand plasma
by only o.25L)
E.g
- D5W.
- NS 0.9 % (used to correct EC volume deficit),
- RL (contain K & Ca + NaCl), used to correct
dehydration, Na depletion and GI losses
Used
to replace cellular fluid
Provide free water for excretion of body wastes
Treat hypernatremia
E.g half strength saline(0.45%NaCl)
Excessive infusion lead to IVF depletion,
decrease BP, cellular edema and cell damage
Cell in a hypotonic solution
Administered
by central veins
Draw water from the ICF to the ECF lead to
cell shrinkage
Can cause ECF excess in rapid administration
E.g G\S, N/S 3%, GW 25% or 50%.
Cell in a hypertonic solution
Choosing
intravenous
site
Fluid Overload:
- Due to excess IVF, renal, hepatic or cardiac disease.
- S&S: crackles, edema, Wt gain, dyspnea, rapid shallow
breathing
- Rx: decrease IV rate, monitor V\S, assess BS, high fowler’s
position, inform doctor
- Complication can occur: HF, PE.
Air Embolism:
- Associated with cannulation of central veins
- S&S: dyspnea, cyanosis, hypotension, chest, shoulder and LBP.
- RX: clamping cannula immediately, put pt on the left side on
trendelenburg position, assess V\S and breathing sound, O2,
- Complication: shock and death.
Septicemia and Infection:
- Induced by pyrogenic substances
- S&S: elevated T, backache, headache, increase
P&RR, N, V, D, chills and shaking, general malaise.
- Causes: contamination of IV product, break in sterility
- RX: symptomatic, culturing IV cannula, tubing, or
solution.
Infiltration
-
-
-
and extravasations:
Infiltration: administration of fluid into surrounding tissue
S&S: edema around insertion site, coolness, discomfort, decrease
flow rate.
If infusion continue despite the blocking of venous flow this
indicate infiltration.
Rx: stop infusion, apply warm compress
Phlebitis:
-
Inflammation of the vein
Can develop from poor hand hygiene, lack of aseptic technique
S&S: redness, warmth, pain or tenderness, swelling
Rx: D\C IV, apply warm compress.
Hematoma:
-
-
Blood leak to the surrounding tissue
S&S: ecchymosis, immediate swelling, leakage of blood at
the insertion site.
Rx: remove needle and cannula, apply light pressure with
sterile dressing, ice for 24hr’s, elevate the extremity.
Clotting
and obstruction
- Due to kinked IV tube, very slow flow rate, empty
IV bag
- S&S : decrease flow rate, blood back in to IV tubing
- Rx: D\C IV line, avoid milking or irrigating the
tube, neither the infusion rate nor the container
should be raised.
Thrombophelibitis.