Page 129 - Critical Care Notes

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■ Administer morphine to manage pain and anxiety.
■ Administer inotropic agents if heart failure present.
■ Prevention:
■ Enoxaparin (Lovenox) 30–40 mg daily
■ Dalteparin (Fragmin) 2,500–5,000 units preoperatively and postoperatively
■ Heparin 5,000 units every 8 hr
■ Fondaparinux (Arixtra)
■ Tinzaparin (Innohep)
■ Progression to warfarin (Coumadin) once patient is well anticoagulated
■ Leg exercises: dorsiflexion of the feet
■ Frequent position changes, ambulation
■ Intermittent pneumonic leg compression devices and antiembolism
stockings
Carbon Monoxide (CO) Toxicity
CO poisoning or toxicity is defined as an abnormal level of CO in the blood-
stream. Normal carboxyhemoglobin (COHgb) level for nonsmokers is <2%; for
smokers it is 5% but may be as high as 13%.
COHgb level >60% → cardiac toxicity, neurotoxicity, systemic acidosis, respi-
ratory arrest, death.
Pathophysiology
CO affinity for Hgb is 200–300 times that of O 2 . CO binds with Hgb →↓ O 2 bind-
ing sites → more CO binds → carboxyhemoglobin forms → CO changes struc-
ture of Hgb molecules → more difficult for O 2 to bind →↓ O 2 to tissues → tissue
ischemia and hypoxemia → acute respiratory failure, ARDS, cerebral hypoxia,
end-organ dysfunction and death.
CO as an inflammatory mediator → tissue damage with ↑ capillary leakage
and edema → tracheal and bronchial constriction.
CO →↓ activity of nitric oxide → (1) peripheral vasodilation →↓ cerebral blood
flow and systemic hypotension; (2) formation of free radicals → endothelial dam-
age and oxidative damage to brain; myocardial depression and arrhythmias →
↓ cardiac output → impaired tissue perfusion.
Clinical Presentation
Early signs: patient may appear intoxicated:
■ COHgb saturation of ≤10% possible with no symptoms
■ Headache, nausea, and vomiting with COHgb of ≥20%
■ Diarrhea
■ General fatigue, weakness
■ Difficulty staying focused, dizziness
■ Flu-like symptoms

RESP