Pre and Post op care

Question 1

__ __ __ which indicates the presence of CHF, is the worst single finding predicting high cardiac risk.

If at all possible, treatment with ACE inhibitors, BBs digitalis and diuretics should precede ___.

Answer 1

Jugular venous distension which indicates the presence of CHF, is the worst single finding predicting high cardiac risk.

If at all possible, treatment with ACE inhibitors, BBs digitalis and diuretics should precede surgery.

Question 2

___ ____ is the second worst predictor of cardiac complications.

Operative mortality within __ months of the infarct is 40%, but drops to 6% after __ months.

Therefore, delaying surgery longer than 6 months from MI is the best course of the action. If surgery cannot be safely delayed, admission to the ICU before surger is recommended to optimize cardiac performance.

Answer 2

Recent MI is the second next worst predictor of cardiac complications. Operative mortality within 3 months of the infarct is 40%, but drops to 6% after 6 months.

Therefore, delaying surgery longer than 6 months from MI is the best course of the action. If surgery cannot be safely delayed, admission to the ICU before surger is recommended to optimize cardiac performance.

Question 3

____ is by far the most common cause of increased pulmonary risk and the problem is compromised ___ (high PCO2, lowed forced expiratory volume in 1 second (FEV1), rather than compromised O2.

The smoking history of the presence of chronic obstruction pulmonary disease (COPD) should lead to ___.

Start with ____ and if abnormal, obtain an ____.

Cessation of smoking for ____ and intensive respiratory therapy, PT, expectorants, incentive spirometry, humified air) should ___ surgery.

Answer 3

Smoking is by far the most common cause of increased pulmonary risk and the problem is compromised ventilation (high PCO2, lowed forced expiratory volume in 1 second (FEV1), rather than compromised O2.

The smoking history of the presence of chronic obstruction pulmonary disease (COPD) should lead to evaluation.

Start with PFTs and if abnormal, obtain an arterial blood gas.

Cessation of smoking for 8 weeks and intensive respiratory therapy *PT, expectorants, incentive spirometry, humified air) should precede surgery.

Question 4

Predictors of ___ (organ?) risk mortality are stratified by the ___-___ classification system. The contibuting factors can be remembered as the ABCDEs:

A___

B___

C___

D___

E___

Predict surgical mortality as follows:

~40% mortality is predictable with bilirubin >__mg/dL, albumin <__ g/dL, prothrombin time >__ sec or encephalopathy.

80-85% mortality is predictable is 3 of the above are present (close to 100% is all 4 exist) or with either bilirubin alone >_ mg/dL, albumin <_g/dL or blood ammonia concentration >___ mg/dL.

Answer 4

Predictors of hepatic risk mortality are stratified by the Child-Pugue classification system. The contibuting factors can be remembered as the ABCDEs:

Ascites

Bilibruin high

Clotting

Diet (serum albumin)

Encephalopathy

Predict surgical mortality as follows:

~40% mortality is predictable with bilirubin >2mg/dL, albumin <3 g/dL, prothrombin time >16 sec or encephalopathy.

80-85% mortality is predictable is 3 of the above are present (close to 100% is all 4 exist) or with either bilirubin alone >4 mg/dL, albumin <2g/dL or blood ammonia concentration >150mg/dL.

Question 5

Severe nutritional depletion is identified by one or more of the following:

1. Loss of __% of body weight over 6 months
2. Serum albumin <__ g/dL
3. Anergy to skin antigens
4. Serum transferrin level <__mg/dl)

Operative risk is multiplied significantly in those circumstancs. Suprisingly, as few as 4-5 days of ___ nutritonal support (preferably via the ___) can make a big difference, and 7-10 days would be optimal if the surgery can be deferred for that long.

Answer 5

Severe nutritional depletion is identified by one or more of the following:

1. Loss of 20% of body weight over 6 months
2. Serum albumin <3 g/dL
3. Anergy to skin antigens
4. Serum transferrin level <200 mg/dl)

Operative risk is multiplied significantly in those circumstancs. Suprisingly, as few as 4-5 days of preop nutritonal support (preferably via the gut) can make a big difference, and 7-10 days would be optimal if the surgery can be deferred for that long.

Question 6

__ __ (clue: metabolic syndrome)is an absolute contraindication to surgery. Rehydration, return of urinary output and at least partial correction of the ____ and ____ must be achieved before surgery.

Answer 6

Diabetic coma is an absolute contraindication to surgery. Rehydration, return of urinary output and at least partial correction of the acidosis and hyperglycemia must be achieved before surgery.

Question 7

Malignant hyperthermia develops shortly after the onset of the anesthetic (typically attributed to halothane or succinylcholine).

Temp >104 and metabolic ___, ___calcemia and __kalemia also occur.

FH may exist.

Treatment is ____, 100% O2, correction of the acidosis, and cooling blankes.

Monitor postop for _____.

Answer 7

Malignant hyperthermia develops shortly after the onset of the anesthetic (typically attributed to halothane or succinylcholine).

Temp >104 and metabolic acidosis, hypercalcemia and hyperkalemia also occur.

FH may exist.

Treatment is IV dantrolene, 100% O2, correction of the acidosis, and cooling blankes.

Monitor postop for development of myoglobinuria.

Question 8

Bacteremia is seen within ___ - ____ minutes of invasive procedures (instrumentation of the __ __ is a classic example) and presents as chills and temp spike as high as 104.

Draw multiple sets of blood cultures and start empiric abx.

Answer 8

Bacteremia is seen within 30-45 minutes of invasive procedures (instrumentation of the urinary tract is a classic example) and presents as chills and temp spike as high as 104.

Draw multiple sets of blood cultures and start empiric abx.

Question 9

Postoperative fever (101-103) is caused sequentially by:

A

P

U

D

W

A

“Wind, water, walking, wound”

Answer 9

Postoperative fever (101-103) is caused sequentially by:

Atelectasis

Pneumonia

UTI

Deep venous thrombophlebitis

Wound infection

Abscess (deep)

“Wind, water, walking, wound”

Question 10

____ is the most common source of fever post-op.

Assess the risk for the other causes listed above, listen to the lungs, do a CXR, improve ventilation (deep breathing and coughin, postural drainage, incentive spirometry) and perform a bronchoscopy if needed.

Answer 10

Atelectasis is the most common source of fever post-op.

Assess the risk for the other causes listed above, listen to the lungs, do a CXR, improve ventilation (deep breathing and coughin, postural drainage, incentive spirometry) and perform a bronchoscopy if needed.

Question 11

Pneumonia will happen on day ___ if ____ is not resolved. Fever will persist, leukocytosis will be present and CXR will demonstrate ___. Obtain sputum cultures and treat with appropriate abx.

Answer 11

Pneumonia will happen on day 3 if atelectasis is not resolved. Fever will persist, leukocytosis will be present and CXR will demonstrate infiltrates. Obtain sputum cultures and treat with appropriate abx.

Question 12

UTI typically produces fever starting on post-op day __.

Answer 12

3

Question 13

Deep thrombophlebitis typically produces fever starting around post-op day __.

PE is not sensitive for this pathology, so obtain ___ with ___studies of the deep leg and pelvic veins.

Tx?

Answer 13

Deep thrombophlebitis typically produces fever starting around post-op day 5

PE is not sensitive for this pathology, so obtain US with doppler studies of the deep leg and pelvic veins.

Tx is systemic anticoag intially with heparin or unfracctionated LMWH and transitioned to a long term anticoag like warfarin.

Question 14

Wound infection typically begins to produce fever around post-op day _. PE will reveal erythema, warmth, tenderness and fluctuance.

If only cellulitis is present, treat with ____

If an abscess is present or suspected, the wound must be __ and __

If it is unclear, use both __ and __ can to diagnose.

Answer 14

Wound infection typically begins to produce fever around post-op day 7. PE will reveal erythema, warmth, tenderness and fluctuance.

If only cellulitis is present, treat with Abx.

If an abscess is present or suspected, the wound must be opened and drained

If it is unclear, use both US and CT scan to diagnose.

Question 15

Deep abscesses start producing fever around post-op days __ - ___. __ scan of the appropriate body cavity is diagnostic.

__ __-__ drainage is therapeutic.

Answer 15

Deep abscesses start producing fever around post-op days 10-15. CT scan of the appropriate body cavity is diagnostic.

Percutaneous image-guided drainage is therapeutic.

Question 16

Peri-operative MI may occur during the operation (triggered most commonly by ____) in which case it is detected by the ECG monitor (ST ____, T-wave ____). When it happens, post-op, it is typically within the first 2-3 days, presenting as chest pain in 1/3 of patients and with the complications of the MI in the rest. The most reliable diagnostic test is ____. Mortality is 50-90% and greatly exceeds that of MI not associated with surgery.

Tx: directed at the complications. ___ cannot be used in perioperative setting, but emergecny __ and coronary ___ can be life saving.

Answer 16

Peri-operative MI may occur during the operation (triggered most commonly by HoTN) in which case it is detected by the ECG monitor (ST depression, T-wave flattening). When it happens, post-op, it is typically within the first 2-3 days, presenting as chest pain in 1/3 of patients and with the complications of the MI in the rest. The most reliable diagnostic test is serum troponin-I levels. Mortality is 50-90% and greatly exceeds that of MI not associated with surgery.

Tx: directed at the complications. Thrombolysis cannot be used in perioperative setting, but emergency angioplasty caand coronary stenting can be life saving.

Question 17

Pulmonary embolism typically occurs around Post-op day ___ in elderly or immobilized patients.

Pain is pleuritic, sudden onset, and is accompanied by SOB.

Patient is anxious, diaphoretic, and tachycardic, with prominent distended veins in the neck and forehead (a low CVP virtually excludes the diagnoses).

ABG demonstrate hypoxemia and often hypocapnia.

Diagnosis is with CT angiogram, which is a __ ___ with a large___ ___ bolus timed to pulmonary artery filling.

Answer 17

Pulmonary embolism typically occurs around Post-op day 7 in elderly or immobilized patients.

Pain is pleuritic, sudden onset, and is accompanied by SOB.

Patient is anxious, diaphoretic, and tachycardic, with prominent distended veins in the neck and forehead (a low CVP virtually excludes the diagnoses).

ABG demonstrate hypoxemia and often hypocapnia.

Diagnosis is with CT angiogram, which is a spiral CT with a large IV contrast bolus timed to pulmonary artery filling.

Question 18

Treatment of PE?

Systemic ___ with ___ and should be started immediately after diagnosis.

In decompensated patients with high index of suspicion, consider starting treatment even __ to confirming the diagnosis.

If a PE recurs while anticoagulated or if anticoagulation is contraindicated, place an IVC filter to prevent further embolization from lower extremity DVT.

Answer 18

Systemic anticoagulation with heparin and should be started immediately after diagnosis.

In decompensated patients with high index of suspicion, consider starting treatment even prior to confirming the diagnosis,.

If a PE recurs while anticoagulated or if anticoagulation is contraindicated, place an IVC filter to prevent further embolization from lower extremity DVT.

Question 19

Aspiration is a distinct hazard in awake intubation in combative patients with full stomachs. It can be lethal right away or lead to a ___ injury of the tracheobronchial tree and subsequent pulmonary failure and/or pnuemonia.

Prevention includes strict ____ of oral intake prior to surgery and ____ before induction.

Therapy starts with ____ lavage and removal of acid and particulate matter followed by bronchodilators and respiratory support.

Steroids usually ___ help and so are not necessarily indicated.

___ are only indicated if a patient demonstrates evidence of resultant pneumonia (i.e. luekocytosis, ___ production and culture, and focal ___of CXR).

Answer 19

Aspiration is a distinct hazard in awake intubation in combative patients with full stomachs. It can be lethal right away or lead to a chemical injury of the tracheobronchial tree and subsequent pulmonary failure and/or pnuemonia.

Prevention includes strict restriction of oral intake prior to surgery and antacids before induction.

Therapy starts with bronchoscopic lavage and removal of acid and particulate matter followed by bronchodilators and respiratory support.

Steroids usually don’t help and so are not necessarily indicated.

Abx are only indicated if a patient demonstrates evidence of resultant pneumonia (i.e. luekocytosis, sputum production and culture, and focal consolidation of CXR).

Question 20

Intraoperative tension pneumothorax can develop in patients with traumatized lungs once they are subjected to ___-___ breathing.

They become progressively more ___ to ventilate with rising airway pressure, BP steadily declines and CVP steadily rises.

If the ___ is open, quick ____ can be achieved through the diaphragm but this is not recommended.

A better approach is to place a ___ through the ___ ___ ___ into the pleural spcae.

____ chest tube has to be plcaed following acute decompression.

Answer 20

Intraoperative tension pneumothorax can develop in patients with traumatized lungs once they are subjected to positive-pressure breathing.

They become progressively more difficult to ventilate with rising airway pressure, BP steadily declines and CVP steadily rises.

If the abdomen is open, quick decompression can be achieved through the diaphragm but this is not recommended.

A better approach is to place a needle through the anterior chest wall into the pleural spcae. Formal chest tube has to be plcaed following acute decompression.

Question 21

___ is the first suspected when a post-op patient becomes confused and disoriented. Sepsis is another prime cause. Check ___ and provide ___ support is airway protection is threatened.

ARDs is seen in patients with a complicated post-op course, often complicated by ___ as the precipitating event. There are __ pulmonary infiltrates and ___, with no evidence of CHF. The enterpiece of therapy is __ with low volume ventilation as excessive ventilatory volumes have been demonstrated to result in barotrauma. A source of sepsis must be sought and corrected.

Answer 21

Hypoxia is the first suspected when a post-op patient becomes confused and disoriented. Sepsis is another prime cause. Check ABG and provide respiratory support is airway protection is threatened.

ARDs is seen in patients with a complicated post-op course, often complicated by sepsis as the precipitating event. There are bilateral pulmonary infiltrates and hypoxia, with no evidence of CHF. The enterpiece of therapy is PEEP with low volume ventilation as excessive ventilatory volumes have been demonstrated to result in barotrauma. A source of sepsis must be sought and corrected.

Question 22

__ __ - very common in the alcoholic whose drinking is suddenly interupted by surgery. During post-op day 2 or 3, the pt gets confused, has hallucinations, and becomes combative.

IV ___ are the standard therapy, but oral alcohol is available at most hospitals for this indication.

Answer 22

DT - very common in the alcoholic whose drinking is suddenly interupted by surgery. During post-op day 2 or 3, the pt gets confused, has hallucinations, and becomes combative.

IV benzos are the standard therapy, but oral alcohol is available at most hospitals for this indication.

Question 23

Acute hyponatremia can produce confusion, convulsions and eventually coma, and even death (water intoxication).

This can be inadvertently induced by the liberal administration of __-___ IV fluids (like ___) in a post-op patient with high levels of ___ hormone (triggered by the response of trauma).

Answer 23

Acute hyponatremia can produce confusion, convulsions and eventually coma, and even death (water intoxication).

This can be inadvertently induced by the liberal administration of sodium-free IV fluids (like D5W) in a post-op patient with high levels of ADH hormone (triggered by the response of trauma).

Question 24

____ can also be a source of confusion, lethargy, and potentially coma, and rapidly induced by large, unreplaced water loss.

Surgical damage to the ___ ___ with unrecognized diabetes insipidous is a good example.

Unrecognized ___ diuresis can also do it.

Rapid replacement of the fluid deficit is needed, but to “cushion” the impact on tonicity, many prefer to use ___ or ___ normal saline (NS), rather than ___.

Answer 24

Hypernatremia can also be a source of confusion, lethargy, and potentially coma, and rapidly induced by large, unreplaced water loss.

Surgical damage to the posterior pit. with unrecognized diabetes insipidous is a good example.

Unrecognized osmotic diuresis can also do it.

Rapid replacement of the fluid deficit is needed, but to “cushion” the impact on tonicity many prefer to use D51/2 or D51/3 normal saline (NS), rather than D5W.

Question 25

Ammonium intoxication is a common source of coma in the ___ patient with bleeding __ __ who undergoes a __ shunt

Answer 25

Ammonium intoxication is a common source of coma in the cirrhotic patient with bleeding esophageal varices who undergoes a portocaval shunt.

Question 26

Post-op urinary retention is extremely common, particularly after surgery in the lower abdomen, pelvis, perineum or groin.

The patient feels the need to void, but cannot do it.

Bladder catheterization should be performed __-__ hours post-op, if no spontaneous ___ has occurred.

Indwelling (Foley) catheter placement is indicated at the second (some say third) consecutive catheterization.

Answer 26

Post-op urinary retention is extremely common, particularly after surgery in the lower abdomen, pelvis, perineum or groin.

The patient feels the need to void, but cannot do it.

Bladder catheterization should be performed 6-8 hours post-op if no spontaneous voiding has occurred.

Indwelling (Foley) catheter placement is indicated at the second (some say third) consecutive catheterization.

Question 27

Zero urinary output typically is caused by a mechanical problem, rather than a biologic one. Look for a plugged or kinked ____, and flush the tubing to dislodge any __ that may have formed.

Answer 27

Zero urinary output typically is caused by a mechanical problem, rather than a biologic one. Look for a plugged or kinked catheter, and flush the tubing to dislodge any clot that may have formed.

Question 28

Low urinary output (<__ mL/kg/hr) in the presence of normal perfusing pressure (i.e. not because of shock) represents either __ __ or __ __ injury.

A low tech diagnostic test is a ___ challenge. A bolus of ___ mL of IV fluid infused over __-__ minutes.

Dehydrated patients will respond with a temporary increase in urinary output, whereas those in ___ ___ will not do so.

A more scientific test is to measure urinary sodium. It will be <___ or <___ mEq/L in the dehydrated patient with normally functional kidneys, while it will exceed ___ mEq/L in cases of renal failure.

A more scientific test is to calculate the fractional excretion of sodium, or FeNa. In order to calculate the FeNa, plasma and urinary sodium and creatinine, must be measured. In acute kidney injury, the ratio is >2; in hypovolemia it is <1.

Answer 28

Low urinary output (<__ mL/kg/hr) in the presence of normal perfusing pressure (i.e. not because of shock) represents either __ __ or __ __ injury.

A low tech diagnostic test is a ___ challenge. A bolus of ___ mL of IV fluid infused over __-__ minutes.

Dehydrated patients will respond with a temporary increase in urinary output, whereas those in ___ ___ will not do so.

A more scientific test is to measure urinary sodium. It will be <10 or <20 mEq/L in the dehydrated patient with normally functional kidneys, while it will exceed 40 mEq/L in cases of renal failure.

A more scientific test is to calculate the fractional excretion of sodium, or FeNa. In order to calculate the FeNa, plasma and urinary sodium and creatinine, must be measured. In acute kidney injury, the ratio is >2; in hypovolemia it is <1.

Question 29

Paralytical ileus is to be expected in the first few days after __ __. Bowel sounds are absent or ___active and there is no passage of gas. There may be mild distension, but there is no pain. Paralytic ileus is prolonged by ___kalemia.

Answer 29

Paralytical ileus is to be expected in the first few days after abdominal surgery. Bowel sounds are absent or hypoactive and there is no passage of gas. There may be mild distension, but there is no pain. Paralytic ileus is prolonged by hypokalemia.

Question 30

Early mechanical bowel obstruction because of adhesions can happen during pregnancy during the postop period. What was probably assumed to be __ __ not resvoling after 5-7 days is most likely an early mechanical bowel obstruction.

Xray will show ___ loops of ___ bowel and air fluid levels.

Dx is confirmed with an ___ ____ scan that demonstrates a transition point between proximal dilated bowel and distal ___ bowel at the site of the obstruction. Surgical intervention is needed to correct the problem.

Answer 30

Early mechanical bowel obstruction because of adhesions can happen during pregnancy during the postop period. What was probably assumed to be paralytic ileus not resvoling after 5-7 days is most likely an early mechanical bowel obstruction.

Xray will show dilated loops of small bowel and air fluid levels.

Dx is confirmed with an abdominal CT scan that demonstrates a transition point between proximal dilated bowel and distal collapsed bowel at the site of the obstruction. Surgical intervention is needed to correct the problem.

Question 31

___ ___ or pseudo-obstruction is a poorly understood (but very common) conditions that could be described as a “__ __ of the colon”

It does not follow abdominal surgery but is classically seen in elderly sedentary patients (Alzheimers, nursing home) who have become further immobilized, owing to surgery elsewhere (broken hip, prostatic surgery).

Patients develop abdominal distention without tenderness, and Xray shows a massively dilated colon.

After fluid and electrolyte correction, it is imperative that mechanical obstruction be ruled out radiologically or by endoscopy, before giving IV ____ to restore colonic motility. A long rectal tube is also commonly used.

Answer 31

Ogilvie Syndrome or pseudo-obstruction is a poorly understood (but very common) conditions that could be described as a “paralytic ileus of the colon”

It does not follow abdominal surgery but is classically seen in elderly sedentary patients (Alzheimers, nursing home) who have become further immobilized, owing to surgery elsewhere (broken hip, prostatic surgery).

Patients develop abdominal distention without tenderness, and Xray shows a massively dilated colon.

After fluid and electrolyte correction, it is imperative that mechanical obstruction be ruled out radiologically or by endoscopy, before giving IV neostigmine to restoire colonic motility. A long rectal tube is also commonly used.

Question 32

Wound dehiscence is typically seen around post op day ___ after open lap. The wound looks intact, but large amounts of pink “____ colored” fluid are noted to be soaking the dressing; this is peritoneal fluid. Reopration is needed to avoid peritonitis and evisceration.

Answer 32

Wound dehiscence is typically seen around post op day ___ after open lap. The wound looks intact, but large amounts of pink “salmon-colored” fluid are noted to be soaking the dressing; this is peritoneal fluid. Reopration is needed to avoid peritonitis and evisceration.

Question 33

____ is a catatrophic complication of wound dehiscence, where the skin itself opens up and the __ contents rush out.

It typically happens when the patient (who may not have been recognized as having dehiscence) coughs, strains, or gets out of bed.

The patient must be kept in bed and the towel covered with large sterile dressings soaked with warm saline. Emergency abdominal closure is required.

Answer 33

Evisceration is a catatrophic complication of wound dehiscence, where the skin itself opens up and the abdominal contents rush out.

It typically happens when the patient (who may not have been recognized as having dehiscence) coughs, strains, or gets out of bed.

The patient must be kept in bed and the towel covered with large sterile dressings soaked with warm saline. Emergency abdominal closure is required.

Question 34

Fistula of the GI tract is recognized because bowel contents leak out through a wound or drainsite. It may harm the patient in a number ways:

1. If it does not empty completely to the outside but leaks into a cavity which then leaks out, an ___ may develop and lead to sepsis; complete drainage is the required treatment.
2. If it drains freely, ____ is not encountered (patient is typically afebrile with no signs of peritoneal irritation) though there are 3 other potential problems:
   - Fluid and electrolye loss
   - Nutritonal depletion
   - Erosion and digestion of the abdominal wall.

These problems are related to location and volume of the fistula:

• non-existent in the distal colon
• present but manageable in low-volume fistula (up to 200-300 ml/day).
• upper GI fistulas (stomach, duodenum, upper jejunum)
• daunting in high-volume (several liters per day) fistulas in upper GI tract

Answer 34

Fistula of the GI tract is recognized because bowel contents leak out through a wound or drainsite. It may harm the patient in a number ways:

1. If it does not empty completely to the outside but leaks into a cavity which then leaks out, an abscess may develop and lead to sepsis; complete drainage is the required treatment.
2. If it drains freely, sepsis is not encountered (patient is typically afebrile with no signs of peritoneal irritation) though there are 3 other potential problems:
   - Fluid and electrolye loss
   - Nutritonal depletion
   - Erosion and digestion of the abdominal wall.

These problems are related to location and volume of the fistula:

• non-existent in the distal colon
• present but manageable in low-volume fistula (up to 200-300 ml/day).
• upper GI fistulas (stomach, duodenum, upper jejunum)
• daunting in high-volume (several liters per day) fistulas in upper GI tract

Question 35

Fistula of the GI tract

Fluid and electrolyte replacement, nutritonal support (preferably elemental diets delivered beyond the fistula), and compulsive protection of the abdominal wall (frequent dressing changes, suction tubes, “ostomy” bags) are done to keep the patient alive until nature heals the fistula. Nature will do so if none of the following are present to prevent wound healing (mnemonic FRIENDS).

Answer 35

Fistula of the GI tract

Fluid and electrolyte replacement, nutritonal support (preferably elemtnay diets delivered beyond the fistula), and compulsive protection of the abdominal wall (frequent dressing changes, suction tubes, “ostomy” bags) are done to keep the patient alive until nature heals the fistula. Nature will do so if none of the following are present to prevent wound healing (mnemonic FRIENDS)

F-foreign body

R-radiation injury

I-infection or inflammatory bowel disease

E-epitheliazation

N-neoplasm

D-distal obstruction

S-steroids

Question 36

Hypernatremia invariably means that the patients has lost water (or other hypotonic fluids) and has developed hypertonicity. Every 3 mEq/L that the serum sodium concentration is >___ represents roughly _ L of water lost.

140/3 - 1

Answer 36

Hypernatremia invariably means that the patients has lost water (or other hypotonic fluids) and has developed hypertonicity. Every 3 mEq/L that the serum sodium concentration is >140 represents roughly 1 L of water lost.

Question 37

Treatment of hypernatremia requires volume repletion, but done in such a way that volume is corrected rapidly (in a matter of hours) while tonicity is only gently “nudged” in the right direction (and goes back to normal in a matter of days). This is achieved by using D5____ rather than D5W.

If the hypernatremia develops rapidly, it will produce CNS symptoms (the brain has not had time to adapt) and correction can be safely done with more diluted fluid (D51/3 NS, or even D5W).

Answer 37

Treatment of hypernatremia requires volume repletion, but done in such a way that volume is corrected rapidly (in a matter of hours) while tonicity is only gently “nudged” in the right direction (and goes back to normal in a matter of days). This is achieved by using D51/2NS rather than D5W.

If the hypernatremia develops rapidly, it will produce CNS symptoms (the brain has not had time to adapt) and correction can be safely done with more diluted fluid (D51/3 NS, or even D5W).

Question 38

Hyponatremia means that water has been retained and hypotonicity has developed, but there are 2 different scenarios (easily distinguishible by the clinical circumstances).

In one scenario, a patient who starts with normal fluid volume adds to it by retaining water because of the presence of inappropriate amounts of __ (post op water intoxication or inappropriate ___ secreted by tumors).

In the other scenario, a patient who is losing large amounts of isotonic fluids (typically from the GI tract) is forced to ____ water if he has not received appropriate replacement with isotonic fluids.

Rapidly developing hyponatremia (water intoxication) produces CNS symptoms (the brain has not had time to adapt), and requires careful use of hypertonic saline (3% or 5%).

In ___ developing hyponatremia from inappropriate ADH, the brain has time to adapt and therapy should be water restriction.

In the case of the hypovolemic, dehydrated patient losing GI fluids and forced to retain water, volume restoration with isotonic fluids (__ or ___) will provide prompt correction of the hypovolemia and allow the body to slowly and safely unload the retained water and return the tonicity to normal.

Answer 38

Hyponatremia means that water has been retained and hypotonicity has developed, but there are 2 different scenarios (easily distinguishible by the clinical circumstances).

In one scenario, a patient who starts with normal fluid volume adds to it by retaining water because of the presence of inappropriate amounts of ADH (post op water intoxication or inappropriate ADH secreted by tumors).

In the other scenario, a patient who is 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,

Rapidly developing hyponatremia (water intoxication) produces CNS symptoms (the brain has not had time to adapt), and requires careful use of hypertonic saline (3% or 5%).

In slowly developing hyponatremia from inappropriate ADH, the brain has time to adapt and therapy should be water restriction.

In the case of the hypovolemic, dehydrated patient losing GI fluids and forced to retain water, volume restoration with isotonic fluids (NS or LR) will provide prompt correction of the hypovoelmia and allow the body to slowly and safely unload the retained water and return the tonicity to normal.

Question 39

Hypokalemia develops slowly (over days) when K+ is lost in the ___ or in the urine and not replaced. Hypokalemia develops rapidly (over hours) when K+ moves into cells, most notably during ___ ___. Therapy is obviously K+ replacement. Remember that the safe “speed limit” of IV K+ administration is __ mEq/hr.

Answer 39

Hypokalemia develops slowly (over days) when K+ is lost in the GI tract or in the urine and not replaced. Hypokalemia develops rapidly (over hours) when K+ moves into cells, most notably during diabetic ketoacidosis. Therapy is obviously K+ replacement. Remember that the safe “speed limit” of IV K+ administration is 10 mEq/hr.

Question 40

Hyperkalemia occurs slowly if the kidney cannot excrete K+ (renal failure, aldosterone antagonists) and it will occur rapidly if K+ is being dumped from the cells into the blood (crushing injuries, dead tissue, acidossi). The ultimate therapy is ____ but while waiting, we can push K+ into cells by giving ___% ___ and ___ sucking itout of the GI tract (NG suction, exchange resins such as ____ if the pts bowels are working), or neutrlizing its affects on cellular memrbane (IV ___).

Answer 40

Hyperkalemia occurs slowly if the kidney cannot excrete K+ (renal failure, aldosterone antagonists) and it will occur rapidly if K+ is being dumped from the cells into the blood (crushing injuries, dead tissue, acidossi). The ultimate therapy is hemodialysis but while waiting, we can push K+ into cells by giving 50% dextrose and insulin, sucking it out of the GI tract (NG suction, exchange resins such as Kayexelate if the pts bowels are working), or neutrlizing its affects on cellular memrbane (IV calcium).

Question 41

__ __ can occur from any of the following:

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)

Tx: directed at the underlying cause, though in all cases, administration of bicarb would temporarily help correct pH. Bicarb therapy, however, is ideal only when the initial problem is bicarb loss (it corrects pH and it addresses the underlying problem). In other cases, it risks producing a rebound ___ once the underlying prob is corrected. Thus, correction of the underlying problem–rather than bicarb administration–is the preferred therapy.

Answer 41

Metabolic acidosis can occur from any of the following:

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)

Tx: directed at the underlying cause, though in all cases, administration of bicarb would temporarily help correct pH. Bicarb therapy, however, is ideal only when the initial problem is bicarb loss (it corrects pH and it addresses the underlying problem). In other cases, it risks producing a rebound alkalosis once the underlying prob is corrected. Thus, correction of the underlying problem–rather than bicarb administration–is the preferred therapy.