Pre-op/Post-op Flashcards
Under what ejection fraction is surgery contraindicated
EF < 35%
What is single most predictive risk factor for preoperative heart complications
Jugular vein distension
Give ACEIs, beta-blockers, digitalis and diuretics before operating
What is the approach to pt with recent transmural or subendocardial MI
Non-emergent: delay surgery 6 months
Emergent: admit to SICU day before surgery
What causes increased pulmonary risk, how is it approached
Smoking
Cessation 8 weeks pre-op, intensive respiratory therapy
Hepatic risk factors for mortality
Increased bilirubin
Decreased albumin
Increased PT
ascites, encephalopathy
For how long must nutritional depletion be corrected before surgery
Ideally 7 days via the gut
What components of diabetic coma must be corrected before surgery
Rehydration
Return of urinary output
Acidosis
Hyperglycemia
Tx for malignant hyperthermia
IV dantrolene
100% O2
Correction of acidosis
Cooling blankets
Tx for intraoperative bacteremia (45 mins into surgery temp spikes to 104 with chills)
Blood cultures x 3
Empiric antibiotics
Post-op fever day 1 and tx
Atelectasis
Bronchoscopy
Post-op fever day 3 with infiltrates on CXR
Pneumonia
Post-op fever day 3 with negative CXR
UTI
order urine cultures and UA
Post-op fever day 5 and tx
Deep thrombophlebitis
Anticoagulate with heparin
Dx by deep leg and pelvic doppler
Post-op fever day 7 and tx
Wound infection
antibiotics if cellulitis, I&D if abscess
Dx best by ultrasound
Post-op fever day 10-15 and tx
Deep abscess
Percutaneous radiographically guided drainage
Dx by CT
Cause of peri- and post-operative MI and tx
Peri: hypotension
Most commonly 2-3 days postop
Tx includes angioplasty and stents
Acute shortness of breath post-op day 7
Tx?
Pulmonary embolism
Heparinization, IVC filter if recurrent or if anticoagulation is contraindicated
Tx for aspiration
Bronchoscopic lavage, bronchodilators and respiratory support
Tx of intraoperative tension pneumothorax
Decompression through diaphragm or anterior chest wall
Chest tube
Can occur while bagging pt with lung trauma
Seen in patients with difficult post-op course
Precipitating event usually sepsis
ARDS
Tx for ARDS
PEEP without excessive volume
Correct sepsis
Post-op day 2-3 confusion, combativeness and hallucinations
Tx?
Delirium tremens
IV benzodiazepines
Confusion, convulsions, coma, death in a pt who received D5W and had high levels of ADH
Tx?
Hyponatremia/water intoxication
Can give small amounts of hypertonic saline and osmotic diuretics but this is controversial
Large unreplaced urinary losses
Rapid weight loss
Rising serum sodium in pt with confusion, lethargy, coma
Tx?
Hypernatremia
Tx is D5 with 1/2 or 1/3 NS
Etiology of hypernatremia
Unrecognized surgical damage to posterior pituitary (iatrogenic diabetes insipidus)
Unrecognized osmotic diuresis
Coma in a cirrhotic patient with bleeding esophageal varices who undergoes portocaval shunt
Ammonium intoxication
Cause of zero urine output
Usually plugged or kinked catheter
Cause of low urine output (< 0.5mL/kg/h)
Dehydration
Acute renal failure
How do you differentiate causes of low urine output
Measure fractional excretion of sodium
>1 is renal failure
Painless abdomen, mild distension
No bowel sounds, no passage of gas
Paralytic ileus
Ileus after post-op day 5, 6, 7
CT shows transition point between dilated proximal bowel and distal collapsed bowel
Early mechanical bowel obstruction
Due to adhesions
What is Ogilvie syndrome
Paralytic ileus of the colon
In sedentary elderly patients who have become further immobilized
Dx and tx of Ogilvie syndrome
Massively dilated colon on Xray or endoscopy and rule out obstruction
tx with IV neostigmine or long rectal tube
Salmon-colored fluid soaking dressings after post-op day 5 of open laparotomy
Wound dehiscence
Tx of evisceration (complication of wound dehiscence)
Bed rest, cover bowel with large sterile saline-soaked dressings, emergency abdominal closure
Tx for GI fistulas
Fluid and electrolyte replacement
Nutritional support
Protection of the abdominal wall while fistula heals naturally
Etiology and tx of hypokalemia
Loss from GI and urinary fluids (slowly)
Correction of DKA (rapidly)
Potassium replacement 10 mEq/h
Etiology and tx of hyperkalemia
Renal failure (slowly) Crushing injuries, acidosis (rapidly)
IV calcium, exchange resins, NG suction, insulin and glucose, eventual dialysis
Etiology of metabolic acidosis
DKA, lactic acidosis, loss of buffers from GI, renal failure
In what acidotic state is anion gap unchanged
Loss of buffers from GI tract
Tx of metabolic acidosis
Correct underlying problem
Potassium replacement
Tx for metabolic alkalosis
KCl 5-10 mEq/h
NH4Cl rarely needed
Tx for respiratory alkalosis and acidosis
Improve ventilation in acidosis
Reduce ventilation in alkalosis
How long should aspirin be withheld before surgery?
NSAIDs
Aspirin 7-10 days
NSAIDs 2 days
Preop management of obese patient
ABG, PFTs with bronchodilators
Epidural anesthesia aggressive postoperative pulmonary care
How does CABG affect preop cardiac risk
<5 years will decrease risk
At 10 years 50% are again occluded and no benefit is achieved
