ACLS in the CTICU
Back to topBypass Types
Hypothermic Cardiopulmonary Bypass
Venous cannula in right atria, cannula is aorta. Heart is cooled down, once proper tem is reached, the aorta is cross clamped and cardioplegia is achieved by injection. The blood is pumped from the right atria to a reservoir where blood suctioned from the field also goes to. It is pumped through a heat exchanger and an oxygenator. Anticoagulation with heparin which is reversed with protamine at the completion of the procedure.
Warm Bypass
Total circulatory Arrest with Whole Body Hypothermia
Phenobarb is given to slow cerebral metabolism; the patient may remain unresponsive for 24-48 hours post procedure
Off Pump Bypass
uses cardiac stabilizers to allow the heart to keep beating during surgery
Back to topPost-Operative Care
Post Op platelets may drop to <40000 and may have qualitative defects Hypothermic patients are vasoconstricted with high SVR and low CO Protamine Reactions
- Hypotension
- Anaphylaxis
- Thromboxane release from capillary bed can cause right heart failure
- Give Steroids and Antihistamines
Hypotension
hypovolemia is the most common cause Card. tamponade, MI, Ischemia, Tension Pneumo, Valve Fx Give empiric volume replacement and consider dopamine ? of relative deficiency of vasopressin
Perioperative MI
Trop >5 Sensitivity of 91%, Specificity of 82% (Parrillo)
Postoperative Hypertension
30-60% of patients will develop Increased risk of graft bleeding and aortic dissection Start with nitroprusside, move to ACEI
Atrial / Ventricular Arrhythmias
Heart Block
Post-Op Bleeding
Protamine’s half life is shorter than heparins
Respiratory Complications
Diaphragmatic dysfunction secondary to cold injury of phrenic nerve Have patient sniff while examining diaphragms with UTS or fluoroscopy Pleural Effusions and ARDS
GI
GI bleeding Can have increased billi from RBC breakdown
Neurologic
Post Pump Syndrome-persistent personality changes which can last for years Aortic cross clamping can cause embolization and post-op strokes
Normal Postoperative Care
Most patients will have two mediastinal drainage tubes Pacing wires to the right of midline are usually atrial and to the left are ventricular In uncomplicated cases, patients can be extubated soon post-op, ~7hrs, use t-tube trial Remove tubes/wires as soon as possible Give a-fib prophylaxis with b-blockers Agents to decrease post-op bleeding such as Aprotinin, EACA, or DDAVP ASA and SC heparin Arterial graft spasm proph with Ca-Blockers Patients may need ventricular assist devices(VAD) The post-op cardiac heart is noncompliant, therefore PAOP and CVP may be artificially high; the patient may need volume in the face of these high seemingly high filling pressures. If the heart was chronically volume overloaded from valve insufficiency,
then immediately post-op this same degree of volume should be maintained. Tachycardia is horrible for the stiff heart as adequate filling times are lost. | | |
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