Chapter 3 - Pre-Op and Post-Op Care Flashcards
Ejection fraction under ___% (normal is 55%) poses prohibitive cardiac risk for non-cardiac operations. Incidence of perioperative MI is very high, with mortality for such an event between ___%.
35; 55-90
___, which dates from 1977, is no longer the preferred method of assessing cardiac risk. What is more commonly used now?
Goldman’s index of cardiac risk; functional status based on the ability to cope with life’s demands
While Goldman’s index of cardiac risk is no longer the preferred method of assessing cardiac risk, it remains useful for listing all the findings that predict trouble - list them in descending order of importance.
JVD Recent MI PVCs or any rhythm other than sinus >70 y/o Emergency surgery Aortic valvular stenosis Poor medical condition Surgery within the chest or abdomen
JVD, which indicates the presence of ___, is the worst single finding predicting high cardiac risk. If at all possible, treatment with what medications should precede surgery?
CHF; ACEIs, beta-blockers, digitalis, and diuretics
Recent transmural or subendocardial MI is the next worst predictor of cardiac complications. Operative mortality within 3 months of the infarct is ___%, but drops to ___% after 6 months. Thus, deferring surgery until then is the best course of action. If surgery is imperative sooner, what should be done?
40; 6; admission to the ICU the day before to “optimize cardiac variables”
What is the most common cause of increased pulmonary risk and why?
Smoking; compromised ventilation (high PCO2, low FEV1) NOT compromised oxygenation
What factors should lead to evaluation of pulmonary risk before surgery? What evaluation should be done?
Smoking history; presence of COPD
Start with FEV1 - if abnormal, follow with blood gases.
What should be done to mitigate pulmonary risk before surgery?
Cessation of smoking for 8 weeks and intensive respiratory therapy (PT, expectorants, IS, humidified air)
Two clinical findings and three lab values are used to predict operative mortality in patients with liver disease - what are they?
Encephalopathy and ascites; serum albumin, prothrombin time (INR), and bilirubin (only as it reflects hepatocyte function)
What is the current favorite system for predicting operative mortality in patients with liver disease and how is it stratified?
Child class
Class A - 10% mortality
Class B- 30% mortality
Class C - 80% mortality
Severe nutritional depletion is identified by what clinical factors?
Loss of 20% of body weight over a couple of months
Serum albumin <3
Anergy to skin antigens
Serum transferrin level<200 mg/dL
Discuss operative risk and pre-op support in the setting of severe nutritional depletion.
Operative risk is multiplied manyfold. As few as 4 or 5 days of pre-op nutritional support (preferably via the gut) can make a big difference. 7-10 days would be optimal if surgery can be deferred that long.
Diabetic coma is an absolute contraindication to surgery - what must be done before surgery?
Rehydration, return of urinary output, at least partial correction of the acidosis and hyperglycemia
If the indication for surgery is a septic process, complete correction of all variables will be impossible as long as the septic process is present.
Timing of onset of malignant hyperthermia in the setting of surgery? Presentation?
Develops shortly after the onset of the anesthetic (halothane or succinylcholine)
Temp >104 F
Metabolic acidosis and hypercalcemia may occur
Possible family Hx
Rx malignant hyperthermia?
IV dantrolene 100% oxygen Correction of acidosis Cooling blankets Watch for myoglobinuria
Timing of onset of fever 2/2 bacteremia in the setting of surgery? Presentation?
Seen within 30-45 minutes of invasive procedures (instrumentation of the urinary tract is classic)
Chills and temp spikes to 104+ F
Manage bacteremia s/p surgery?
Blood cultures 3x, start empiric ABX
Although rare, severe wound pain and very high fever within hours of surgery should alert you to the possibility of ___ in the surgical wound.
Gas gangrene
Post-operative fever in the usual range (___ F) is caused sequentially in time by what 6 complications?
101-103; atelectasis -> pneumonia -> UTI -> deep vein thrombophlebitis -> wound infection -> deep abscesses
What is the most common source of post-op fever on the first PO day?
Atelectasis
Management of suspected atelectasis post-op?
Rule out the other causes of fever, listen to the lungs, do a CXR, improve ventilation (deep breathing and coughing, postural drainage, IS)
Ultimate therapy if needed is bronchoscopy
Pneumonia will happen in about ___ days if atelectasis does not resolve. Presentation and management?
3; fever will persist, CXR will show infiltrates. Sputum Cx, Rx with ABX
UTI typically produces fever starting on POD ___. Work-up and Rx?
3; UA and UCx. Rx with ABX
Deep thrombophlebitis typically produces fever starting on POD ___ or thereabouts. Work-up and Rx?
5; Doppler studies of deep leg and pelvic veins is the best diagnostic modality (exam is worthless); anticoagulate with heparin, transition to warfarin