Cd Pestana 03. Pre-Op And Post-Op Care

Front 1

Cardiac risk for noncardiac operations is high when ejection fraction is what?

Back 1

< 35%; normal EF is 55%.

Front 2

Incidence of perioperative MI and mortality for EF <35%?

Back 2

75-85% MI, 55-90% mortality

Front 3

Points assigned in Goldman's index of cardiac risk?

Back 3

Points:

11 - JVD (evidence of CHF)

10 - recent MI (within 6m)

7 - PVC (5+/m) or non-sinus rhythm

5 - > 70y

4 - emergency surgery

3 - aortic valvular stenosis, poor medical condition, or surgery within the chest or abdomen

Higher point = higher risk of cardiac complications

Front 4

What is the single worst finding predicting high cardiac risk?

Back 4

JVD, which indicates CHF

Front 5

Mgmt CHF

Back 5

ACEIs, b-blockers, digitalis, diuretics before surgery

Front 6

How do you reduce risk of cardiac complications for someone who needs surgery, but had an MI within 6m?

Back 6

1) Defer the surgery. For instance, MI within 3m of procedure has an operative mortality of 40%, but only 6% after 6m.

2) Can't defer surgery, send pt to ICU the day before procedure to "optimize cardiac variables."

Front 7

MCC of increased pulmonary risk?

Back 7

Smoking

Front 8

How does smoking increase pulmonary risk?

Back 8

Compromised ventilation (high PCO2, low FEV1); used air is stuck in alveoli.

Front 9

How to assess pulmonary risk?

Back 9

Evaluate pts who smoke or have COPD by finding FEV1 (then ABGs if FEV1 abnl)

Front 10

How can a smoker prepare for his/her surgery?

Back 10

Stop smoking for 8w and undergo intensive respiratory therapy (physical therapy, expectorants, incentive spirometry, humidified air)

Front 11

What are predictors of mortality due to liver (dys)function?

Back 11

1) Bilirubin (reflects hepatocellular function) > 2; > 4 is severe

2) Serum albumin < 3; < 2 is severe

3) Prothrombin time > 16

4) Ascites

5) Encephalopathy (blood ammonia > 150)

40% mortality if 'mild'

80-85% if severe (3 'milds' or any 'severe' situation)

Front 12

What is severe nutritional depletion?

Back 12

1) Loss of 20% of body weight over a couple of months

2) Serum albumin < 3

4) Anergy to skin antigens

5) Serum transferrin < 200 mg/dL (or combination of above)

Front 13

How do you optimize nutrition status in preparation for surgery?

Back 13

Give 4-5 days of preoperative nutritional support (preferably via the gut). 7-10 days best if surgery can be deferred that long.

Front 14

What is an absolute contraindication to surgery?

Back 14

Diabetic coma.

Front 15

What must be achieved before surgery?*

Back 15

Rehydration, return of urinary output, and at least partial correction of the acidosis and hyperglycemia

*Note that not everything will be correctable if a septic process is present

Front 16

A pt in the hospital has a temperature above 104 pre-op. What likely happened?

Back 16

An anesthetic, such as halothane or succinylcholine, was administered, resulting in malignant hyperthermia

Front 17

Mgmt malignant hyperthermia?

Back 17

Watch for development of myoglobinuria; give dantroline, 100% oxygen, correction of acidosis, and cooling blankets

Front 18

It's 30-40 minutes into a procedure and your pt develops chills and a fever spiking to or exceeding 104. What's going on? What do you do?

Back 18

Bacteremia, do blood Cx x 3 and start empiric Abx

Front 19

It's only been a few hours since surgery and your pt is developing severe wound pain and a very high fever, what might be going on?

Back 19

Gas gangrene in the surgical wound

Primary post-op:

1) infection

2) transfusion

3) malignant hyperthermia

Front 20

What might cause post-op fever in the usual range (101-103)?

Back 20

1) Atelectasis (0-1d)

2) PNA (0-3d)

3) UTI (day 3)

4) Deep venous thrombophlebitis (day 5)

5) Wound infection (day seven)

6) Deep abscess (10-15d)

Front 21

Mgmt atelectasis

Back 21

Rule out other causes of fever, listen to the lungs

Dx CXR

Tx improve ventilation (deep breathing and coughing, postural drainage, incentive spirometry), bronchoscopy

Front 22

Mgmt PNA

Back 22

Dx CXR (infiltrates), sputum Cx

Tx Abx

Front 23

Mgmt UTI

Back 23

Dx Urinalysis, Cx urine

Tx Abx

Front 24

Mgmt deep thrombophlebitis

Back 24

Dx doppler deep leg and pelvic veins

Tx Heparin

Front 25

Mgmt wound infxn

Back 25

Dx PE (erythema, warmth, tenderness); sonogram if can't distinguish bt cellulitis and abscess

Tx Abx (if only cellulitis); I&D (if abscess)

Front 26

Mgmt deep abscess

Back 26

Dx CT of appropriate body cavity

Tx percutaneous radiologically guided drainage

Front 27

What usually triggers perioperative MI?

Back 27

Hypotension

Front 28

How does perioperative MI present?

Back 28

EKG ST depression, T-wave flattening

Front 29

How does an MI present post-op?

Back 29

Usu 2-3 days post-op, 1/3 cases will show chest pain and 2/3 will show complications of MI

Front 30

Mgmt peri-/post- op MI

Back 30

Dx Troponin

Tx complications

Front 31

What should and shouldn't be used to treat MI in the perioperative setting?

Back 31

Yes: emergency angioplasty and coronary stent

No: clot busters

Front 32

Your pt is post-op day 7 and is elderly/immobilized. Watch for what?

Back 32

Pulmonary embolus

Front 33

Sx pulmonary embolus?

Back 33

Sudden onset, pleuritic pain accompanied by SOB

Front 34

How does a PE pt look?

Back 34

Anxious, diaphoretic, and tachycardic with prominent distended veins in the neck and forehead

Front 35

What excludes the Dx of PE

Back 35

Low CVP (because there's fluid back up due to "clogged" artery)

Front 36

Mgmt PE?

Back 36

Dx ABG (hypoxemia, hypocapnia); pulm angiogram (gold standard, but rarely done); spiral CT/CT angio w contrast

Tx Heparin; add IVC filter (Greenfield) if PEs recur while anticoagulated or if anticoagulation is contraindicated

Front 37

How can PEs be prevented?

Back 37

By preventing thromboembolism:

1) Compression devices (if pt doesn't have LE fracture)

2) Anticoagulation (high risk pts)

Front 38

What are risk factors for PE?

Back 38

1) Age >40

2) Pelvic or leg fractures

3) Venous injury

4) Femoral venous catheter

5) Anticipated prolonged immobilization

Front 39

What may ensue aspiration?

Back 39

1) Chemical injury of the the tracheobronchial tree

2) Pulmonary failure

3) Secondary pneumonia

4) Death

Front 40

How can aspiration be prevented?

Back 40

NPO and antacids before induction

Front 41

Tx aspiration?

Back 41

Lavage and removal of acid and particulate matter (with the help of bronchoscopy) followed by bronchodilators and respiratory support

Front 42

Your pt has recent blunt trauma with punctures by broken rips, what can develop if your pt undergoes positive-pressure breathing?

Back 42

Intraoperative tension pneumothorax

Front 43

What happens in intraoperative tension pneumothorax?

Back 43

The pt becomes progressively more difficult to "bag," BP steadily declines, and CVP steadily rises

Front 44

Tx intraoperative tension pneumothorax?

Back 44

Open abdomen: quick decompression through the diaphragm

Closed abdomen: insert needle through the anterior chest wall into the pleural space (sneaking in under the drapes)

Place formal chest tube later

Front 45

Post-op pt gets confused and disoriented. What might be going on? Cause? Mgmt?

Back 45

Suspect sepsis-induced hypoxemia. Check ABGs and provide respiratory support.

Front 46

Pt with stormy, complicated post-op course may have what? Caused by?

Back 46

Adult respiratory distress syndrome (ARDS) causd by sepsis

Front 47

Findings in adult respiratory distress syndrome?

Back 47

Bilateral pulmonary infiltrates and hypoxia with no evidence of CHF

Front 48

Tx ARDS?

Back 48

Positive end-expiratory pressure (PEEP), but not too much volume. Also, explore for sepsis and treat if necessary.

Front 49

What may result from excessive ventilatory volumes?

Back 49

Barotrauma

Front 50

An alcoholic suddenly has to stop drinking to undergo surgery. What may ensue?

Back 50

Delirium tremens.

Front 51

On the second or third post-op day, how may a chronic alcoholic who's suddenly stopped drinking present?

Back 51

Confused, have hallucinations, and become combative

Front 52

Tx delirium tremens?

Back 52

IV benzos (but IV alcohol, 5% in 5% dextrose) still preferred by some in surgical community)

Front 53

A pt has confusion, convulsions, and is bridging to coma post-operatively; what may have happened?

Back 53

1) Hyponatremia/"water intoxication;" sodium-free IV fluids (like D5W) were likely quickly introduced and the pt probably has high ADH levels bc he was post-op

2) Hypernatremia through rapid, large, unreplaced water loss

Front 54

Why does a post-op pt have high levels of ADH

Back 54

Trauma induces high levels

Front 55

Charts/labs for this confused and convulsing pt?

Back 55

Large fluid intake, quick weight gain, and rapidly lowering serum sodium concentration (in a matter of hours); hyponatremia

Front 56

How can this confused and convulsing pt's condition be prevented?

Back 56

Including sodium in the IV fluids; some people use small amounts of hypertonic saline (aliquots of 100 mL of 5% or 500 mL of 3%); they may also add osmotic diuretics

Front 57

Two key inciting factors that may lead to hypernatremia?

Back 57

1) Surgical damage to the posterior pituitary with unrecognized diabetes

2) Unrecognized osmotic diuresis

Front 58

Charts hypernatremia

Back 58

Large, unreplaced urinary output, rapid weight loss, and rapidly rising serum sodium concentration

Front 59

Tx unreplaced urinary output, rapid weight loss, and rapidly rising serum sodium concentration?

Back 59

Rapid fluid replacement, but with D5.5 or 5.33 NS rather than D5W

Front 60

A pt w cirrhosis with bleeding esophageal varices undergoes a portocaval shunt. He falls into a coma. What likely happened?

Back 60

Ammonium intoxication; MCC coma in this type of pt

Front 61

Pt feels the need to void, but can't do it. What's going on?

Back 61

Post-op urinary retention.

Front 62

When do pts typically have post-op urinary retention?

Back 62

Typically after surgery in the lower abdomen, pelvis, perineum, or groin

Front 63

Tx need to void post-op but can't?

Back 63

In-and-out bladder catheterization at 6h post-op if no spontaneous voiding has occurred. Foley (indwelling) catheter is inddicated at the second/third consecutive catheterization.

Front 64

A pt is not having any urinary output. What may be going on?

Back 64

Mechanical problem, like a plugged or kinked catheter

Front 65

A pt has low urinary output (less than 0.5 mL/kg/h) in the presence of normal perfusing pressure. What may this be indicative of?

Back 65

Fluid deficit or acute renal failure

Front 66

Mgmt low urinary output?

Back 66

Dx fluid challenge ( bolus 500 mL IV fluid infused over 10-20 min)

1) Dehydration - will increase output (response)

2) Renal failure - still low (no response)

or measure urinary sodium

1) dehydrated pt, good kidneys - < 10-20 mEq/L

2) renal failure - > 40 mEq/L

Or FENa >1 = renal failure

Front 67

A few days after abdominal surgery, a pt presents with absent bowel sounds and no flatulence. There is some abdominal distension, but no pain. What's going on?

Back 67

Paralytic ileus

Front 68

What prolongs paralytic ileus?

Back 68

Pain

Front 69

A patient continues to lack bowel sounds and flatulence and have painless, mild abdominal distension into days 5, 6, and 7 post-op. What's probably going on?

Back 69

Adhesions causing early mechanical bowel obstruction

Front 70

Mgmt adhesions

Back 70

Dx

1) XR (dilated loops of small bowel and air-fluid levels)

2)confirm with CT (transition point bt proximal dilated bowel and distal collapsed bowel at the site of obstruction)

Tx surgery

Front 71

An sedentary old lady who has Alzheimer's and lives in a nursing home can't walk due to a broken hip (prostatic surgery for men; essentially pt is immobilized). What may ensue?

Back 71

She may develop a large, tense (but nontender) abdominal distension, a "paralytic ileus of the colon" known as Ogilvie syndrome.

Front 72

Mgmt Ogilvie syndrome?

Back 72

Dx XR massively dilated colon

Tx 1) fluid and electrolyte correction

2) R/O obstruction (XR/endoscopy)

3) IV neostigmine (restore colonic motility)

Front 73

What do you look for on post-op day 5 of an open laparotomy? What is it and what does it indicate?

Back 73

Pink, "salmon-colored" fluid soaking through the dressings, which is peritoneal fluid- indicative of wound dehiscence.

Front 74

Mgmt pink, soaking "salmon-colored" fluid?

Back 74

For this pink fluid (wound dehiscence), Tx:

1) Tape wound securely

2) Bind abdomen

3) Plan for prompt reoperation to prevent evisceration now or ventral hernia later on

Front 75

You're rounding on a pt around s/p a laparoscopic procedure post-op day 5 and the skin lining her wound suddenly opens up and her abdominal contents rush out! What is this called and when does it typically occur?

Back 75

Called evisceration, it is a compliation of wound dehiscence that typically occurs when a pt coughs, strains, or gets out of bed.

Front 76

Mgmt evisceration?

Back 76

Tx 1) Keep the pt in bed

2) Cover the bowel with large sterile dressings soaked with warm saline

3) Do emergency abdominal closure

Front 77

You're rounding on a pt who's post-op day 7. What are you looking for?

Back 77

Fever; wound erythema, warmth, and tenderness; wound infection.

Front 78

You're rounding on a pt and see bowel contents leaking through a wound or drain site. What's going on?

Back 78

You're witnessing the result of a fistula of the GI tract!

Front 79

You're rounding on a pt and you notice that he has brown stuff leaking through a wound or drain site. This pt also has sepsis. What happened?

Back 79

The pt likely developed a GI fistula in which the bowel contents leak into a "cesspool" that then leaks out (rather than emptying directly and completely to the outside)

Front 80

In a pt who is afebrile, is without peritoneal irritation, and has bowel contents leaking through a wound or drainage site, what are potential problems?

Back 80

1) Fluid and electrolyte loss

2) Nutritional depletion

3) Erosion and digestion of the belly wall

Front 81

What determines whether the complications of a GI fistula in an afebrile pt without peritoneal irritation occur?

Back 81

The location and volume of the fistula:

Chance of complications are -

1) Nonexistent in the distal colon

2) Manageable in low-volume (up to 200-300 mL/d) high GI fistulas (stomach, duodenum, upper jejunum)

3) High in high-volume (several liters per day) fistulas high in the GI tract

Front 82

Tx GI fistula?

Back 82

Tx goal keep the pt alive until nature heals the fistula

1) Fluid and electrolyte replacement

2) Nutritional support (preferrably elemental diets delivered beyond the fistula)

3) Compulsive protection of the abdominal wall (suction tubes, "ostomy"bags)

Front 83

Your patient has a GI fistula. Check for what to maximize healing

Back 83

Don't be FETI3D:
1) Foreign body
2) Epithelialization
3) Tumor
4) Infection
5) Irradiated tissue
6) IBD
7) distal obstruction

Front 84

Your patient has a GI fistula and it's not healing. Check for what on the meds list?

Back 84

Steroids; they prevent healing

Front 85

How can hyponatremia occur?

Back 85

1) Patient starts with normal fluid volume, but has high ADH, so accumulates too much water. Excessive ADH may result from post-op water intoxication or tumor-related SIADH.

2) Pt losing large amounts of isotonic fluids (typically from the GI tract) is forced to retain water if he has not received appropriate replacement with isotonic fluids

Front 86

Tx rapidly developing hyponatremia?

Back 86

Careful use of hypertonic saline (3% or 5%)

Front 87

Tx slowly developing hyponatremia?

Back 87

Water restriction (brain has time to adapt)

Front 88

A hypovolemic, dehydrated pt is losing GI fluids and fored to retain water; how do you treat? What does this do?

Back 88

Volume restoration with isotonic fluids (NS or Ringer lactate); allows prompt correction of the hypovolemia and for the body to slowly and safely unload the retained water and return the tonicity to normal

Front 89

What should be watched for during the correction of diabetic ketoacidosis? Tx?

Back 89

Potassium moves into cells, resulting in rapid development of hypokalemia (hours); Tx by potassium replacement

Front 90

How can hypokalemia develop?

Back 90

1) Loss from GI tract (all GI fluids have lots of K)

2) Loss through urine (loop diuretics, aldosterone)

Front 91

Tx hypokalemia?

Back 91

Potassium replacement (10 mEq/h max; only exceed if you know what you're doing)

Front 92

A pt has renal failure and is taking an aldosterone antagonist (smart move -_-). What's likely to occur?

Back 92

Hyperkalemia

Front 93

What else can cause hyperkalemia?

Back 93

Potassium is dumped from the cells into the blood (eg crush injuries, dead tissue, acidosis)

Front 94

Tx hyperkalemia

Back 94

Early:

1) Push potassium into cells (50% dextrose and insulin)

2) Sucking it out of GI tract (NG suction, exchange resins)

3) Neutralizing effect on the cellular membrane (IV calcium)

Later (best):

Hemodialysis

Front 95

How can metabolic acidosis occur?

Back 95

1) Excessive production of fixed acids (diabetic ketoacidosis, lactic acidosis, low-flow states)

2) Loss of buffers (loss of bicarb-rich fluids from the GI tract)

3) Inability of the kidney to eliminate fixed acids (renal failure)

Front 96

Labs in metabolic acidosis?

Back 96

1) pH < 7.4

2) Low HCO3 <25

3) Anion gap > 10 or 15 (when abnormal acids are piling up in blood)

Front 97

Tx metabolic acidosis (all causes)

Back 97

1) Treat underlying cause* impt!!

2) Administer bicarb (or bicarb precursors, like lactate or acetate) to correct pH IF bicarb loss was the initial problem

3) Replace K if necessary (usu in long-standing acidosis; kidney loses K)

Front 98

When is bicarbonate used as therapy for metabolic acidosis? What happens if it is used in other cases?

Back 98

When the initial problem is bicarbonate loss (it corrects the pH and addresses the underlying problem). If the initial problem is otherwise and bicarbonate is used, "rebound alkalosis" can result

Front 99

A pt loses gastric juices and has excessive administration of bicarb, what's likely to follow?

Back 99

Metabolic alkalosis

Front 100

Labs metabolic alkalosis?

Back 100

pH > 7.4

HCO3 > 25

Excess base

Front 101

Tx metabolic alkalosis

Back 101

Abundant KCl intake (bt 5 to 10 mEq/h; rarely need ammonium chloride or 0.1 N HCl)

Front 102

Impaired or abnormal hyperventilation lead to what?

Back 102

Impaired - respiratory acidosis

Abnormal - respiratory alkalosis

Front 103

Labs respiratory acidosis/alkalosis

Back 103

Abnl PCO2 (low in alk, high in acidosis)

Abnl blood pH

Front 104

Tx respiratory acidosis or alkalosis

Back 104

Acidosis - improve ventilation

Alkalosis - decrease ventilation