4 - Preoperative and Intraoperative Care of the Surgical Patient

The selection and preparation of surgical patients require attention to a number of details.

The _________________ of surgical patients require attention to a number of details.

The patient should always receive a complete physical examination, followed by the appropriate laboratory workup.

The patient should always receive a ____________________ , followed by the appropriate ___________.

A thorough history helps determine the extent of the physical and laboratory examinations.

A ____________ helps determine the extent of the physical and laboratory examinations.

Obtaining preoperative information also allows comparison of the animal’s status before and after surgery (e.g., ability to micturate before and after spinal surgery).

Obtaining preoperative information also allows ______________ before and after surgery (e.g., ability to micturate before and after spinal surgery).

General assessment and stabilization of the surgical patient are discussed in this chapter; preoperative considerations for specific diseases are provided throughout the text.

______________________ of the surgical patient are discussed in this chapter; preoperative considerations for specific diseases are provided throughout the text.

3 important factors under preoperative care

1. HISTORY TAKING

2. PHYSICAL EXAMINATION

3. LABORATORY DATA

A thorough history from the owner or caregiver aids in evaluation of the underlying disease process and identification of other abnormalities that might affect the surgical outcome.

A ________________ or caregiver aids in evaluation of the underlying disease process and identification of other abnormalities that might affect the surgical outcome.

1. signalment

2. diet

3. exercise

4. environment

5. past medical problems

6. recent treatments

7. any evidence of infection

   
   

history taking factors

[history taking] recent treatments factors

anti-inflammatory, antimicrobial, and potentially nephrotoxic or hepatotoxic therapy

Before embarking upon a detailed chronology of endless detail, the presenting complaint should be asked

1. When did the current problem start?

2. What did the problem look like when it first began?

3. Has the problem gotten better or worse, and if so, how?

Before embarking upon a detailed chronology of endless detail, the presenting complaint should be asked

1. _______________

2. ______________________

3. __________________________

Questions should be framed to avoid vague responses and to obtain specific information.

Questions should be framed to avoid ______________ and to ________________.

For example, “When was your dog last vaccinated?” is a better question than “Is your dog current on his vaccinations?”

For example, “_________________________” is a better question than “Is your dog current on his vaccinations?”

• Vomiting

• diarrhea

• altered appetite

• exposure to toxins or foreign bodies

• coughing

• exercise intolerance

• other abnormalities

When obtaining specific info, these factors should be noted

Animals with a history of previous drug reactions or seizures must be identified so that certain drugs can be avoided.

Animals with a ______________________________ must be identified so that certain drugs can be avoided.

The animal should be systematically evaluated during a physical examination, in which all body systems are evaluated.

The animal should be systematically evaluated during a physical examination, in which ________________.

1. body condition

2. attitude

3. mental status

animal’s general condition that should be noted

If indicated, animals should have a neurologic examination and an orthopedic examination in addition to evaluation of the respiratory, gastrointestinal, cardiovascular, and urinary systems.

If indicated, animals should have a __________ examination and an ____________ examination in addition to evaluation of the respiratory, gastrointestinal, cardiovascular, and urinary systems.

Emergencies may allow only a cursory examination until the animal has been stabilized.

Emergencies may allow only a _____________ until the animal has been stabilized.

Evaluation of the preanesthetic physical status is a good determinant of the likelihood of cardiopulmonary emergencies during or after surgery.

Evaluation of the preanesthetic physical status is a good determinant of the ____________________ during or after surgery.

the more deteriorated the physical status, the higher the risk of anesthetic and surgical complications.

the more deteriorated the physical status, the ______________________________________

The animal’s physical status and the procedure to be performed dictate the extensiveness of the laboratory workup.

The animal’s _______________________ dictate the extensiveness of the laboratory workup.

Determination of the hematocrit, total protein (TP), blood urea nitrogen or preferably serum creatinine concentration, and urine specific gravity may suffice for young, healthy animals undergoing elective procedures (e.g., ovariohysterectomy and declawing) and in healthy animals with localized disease (e.g., patellar luxation).

Determination of the ________, __________, ___________ or preferably ________________, and ____________ may suffice for young, healthy animals undergoing elective procedures (e.g., ovariohysterectomy and declawing) and in healthy animals with localized disease (e.g., patellar luxation).

Determination of the hematocrit, total protein (TP), blood urea nitrogen or preferably serum creatinine concentration, and urine specific gravity may suffice for young, healthy animals undergoing elective procedures (e.g., ovariohysterectomy and declawing) and in healthy animals with localized disease (e.g., patellar luxation).

Determination of the hematocrit, total protein (TP), blood urea nitrogen or preferably serum creatinine concentration, and urine specific gravity may suffice for ______, healthy animals undergoing _____________ (e.g., ovariohysterectomy and declawing) and in _____________________ (e.g., patellar luxation).

• complete blood count

• serum biochemistry profile

• urinalysis

• Venous blood gas analysis

if the animal is:

• older than 5 to 7 years even with a physical status of I or II

• has systemic signs

• if the anticipated surgery time is longer than 1 to 2 hours

what are the laboratory tests that should be done?

if the animal is:

• older than 5 to 7 years even with a physical status of I or II

• has systemic signs

• if the anticipated surgery time is longer than 1 to 2 hours

a complete blood count, serum biochemistry profile, and urinalysis should be done.

if the animal is:

• __________________

• _____________

• __________________________

a complete blood count, serum biochemistry profile, and urinalysis should be done.

• dyspnea

• heart murmur

• anemia

• ruptured bladder

• gastric dilation-volvulus

• shock

• hemorrhage

enumerate the systemic signs

Venous blood gas analysis could also be considered to determine the animal’s acid-base status.

Venous blood gas analysis could also be considered to ______________________________________.

The necessity for additional laboratory data is dictated by the animal’s presenting signs and underlying disease

The necessity for additional laboratory data is dictated by the _________________________________________

Identification of associated or underlying disease influences preoperative management, the surgical procedure performed, the prognosis, and postoperative care.

Identification of associated or underlying disease influences ________________, the __________________, the _________, and ________________.

Animals with neoplasia should be evaluated for metastasis (e.g., thoracic radiographs, abdominal ultrasound, and/or lymph node aspiration)

Animals with neoplasia should be evaluated for _________ (e.g., thoracic radiographs, abdominal ultrasound, and/or lymph node aspiration)

1. thoracic radiograph

2. abdominal ultrasound

3. lymph node aspiration

Metastasis test that should be done

Those with cardiac disease should have thoracic radiographs, cardiac ultrasound scans, and/or electrocardiogram

Those _______________ should have thoracic radiographs, cardiac ultrasound scans, and/or electrocardiogram

In endemic areas, the patient’s heartworm status should be checked before surgery

In endemic areas, the __________________ should be checked before surgery

Traumatized animals should have thoracic radiographs so that the diaphragm, pleural space, and lungs can be evaluated for conditions such as pulmonary contusion, pneumothorax, pleural effusion, or diaphragmatic hernia.

________________ should have thoracic radiographs so that the diaphragm, pleural space, and lungs can be evaluated for conditions such as pulmonary contusion, pneumothorax, pleural effusion, or diaphragmatic hernia.

Traumatized animals should have thoracic radiographs so that the diaphragm, pleural space, and lungs can be evaluated for conditions such as pulmonary contusion, pneumothorax, pleural effusion, or diaphragmatic hernia.

Traumatized animals should have thoracic radiographs so that the diaphragm, pleural space, and lungs can be evaluated for conditions such as ______________________________.

Fullbody sedated computed tomography (CT) exams can also be considered for traumatized animals to assess for unidentified injuries.

Full body sedated computed tomography (CT) exams can also be considered for _________________________________.

Although economic considerations are important, a thorough preoperative examination is cost-effective because it often prevents or predicts costly complications.

Although economic considerations are important, a thorough preoperative examination is ____________ because it often prevents or predicts costly complications.

Although economic considerations are important, a thorough preoperative examination is cost-effective because it often prevents or predicts costly complications.

Although economic considerations are important, a thorough preoperative examination is cost-effective because ____________________________________.

I

II

III

IV

V

Enumerate the Rating of Physical Status in Surgical Patients

Physical status I: Healthy with no discernible disease

Physical status I: __________________________

Physical status II: Healthy with localized disease or mild systemic disease

Physical status II: _______________________________

Physical status III: Severe systemic disease

Physical status III: _________________

Physical status IV: Severe systemic disease that is life threatening

Physical status IV: _______________________________

Physical status V: Moribund; patient not expected to live longer than 24 hours with or without surgery

Physical status V: ___________; patient not expected to live longer than 24 hours ______________________

I

Patient is undergoing an elective procedure (e.g., ovariohysterectomy, declaw, castration)

II

Patellar luxation, skin tumor, cleft palate without aspiration pneumonia

III

Pneumonia, fever, dehydration, heart murmur, anemia

IV

Heart failure, renal failure, hepatic failure, severe hypovolemia, severe hemorrhage

V

Endotoxic shock, multiorgan failure, severe trauma

1. PCV/hematocrit

2. Total solids or proteins

3. Blood glucose

4. Blood urea nitrogen (BUN)

5. Alanine aminotransferase

5 Brief Considerations for Selected Clinical Pathologic Findings

PCV/hematocrit

the percentage of whole blood made up of red blood cells (RBCs).

PCV/hematocrit is the percentage of whole blood made up of red blood cells (RBCs).

PCV/hematocrit is the percentage of _____________________________ (RBCs).

PCV/hematocrit mechanixm

1. Whole blood is centrifuged to pellet the red blood cells.

2. Plasma remains at the top.

3. The fraction of packed blood is the hematocrit, read as a percentage.

PCV/hematocrit mechanixm

1. ________________________

2. ___________________________

3. ____________________________

• Decreased RBC production

• Decreased RBC life span

• Blood loss

Causes of Low PCV

Decreased RBC production

example: chronic renal failure

Decreased RBC production

example: _________________

Decreased RBC life span

example: autoimmune diseases, parasite infections

Decreased RBC life span

example: ______________________

Blood loss

example: secondary to trauma, blood-clotting disorders, or gastric ulcers

Blood loss

example:_________________, ______________ or ___________

Causes of Increased PCV

1. Dehydration (common)

2. Absolute polycythemia (rare)

   
   

Causes of Increased PCV

1. ________ (common)

2. ______________ (rare)

   
   

Normal PCV Reference Ranges

• Canine: 37% to 54%

• Feline: 27% to 48%

Normal PCV Reference Ranges

• Canine: _____________

• Feline: _____________

Plasma Proteins & Total Solids (TS) provide information on an animal's plasma protein levels.

______________________ provide information on an animal's plasma protein levels.

Three Major Plasma Proteins

1. Albumin

2. Globulin

3. Fibrinogen

Three Major Plasma Proteins

1. _______

2. _____

3. _________

Elevated Plasma Proteins & Total Solids (TS) values associated with:

• Dehydration

• Malignancies

• Infections

  
  

Elevated Plasma Proteins & Total Solids (TS) values associated with:

• _________

• ________

• _________

  
  

Decreased Plasma Proteins & Total Solids (TS) values associated with:

• Inadequate production (albumin is made in the liver)

• Inadequate intake (starvation)

• Increased loss

• Inadequate absorption from the GIT

Decreased Plasma Proteins & Total Solids (TS) values associated with:

• ________________ (albumin is made in the liver)

• ______________ (starvation)

• ___________

• ____________________

[decreased TS] Increased loss

example: renal disease, blood loss, parasites

[decreased TS] Increased loss

example: __________, ________, _________

[decreased TS] Inadequate absorption from the GIT

example: pancreatic disease, inflammatory bowel disease

[decreased TS] Inadequate absorption from the GIT

example: _____________, _________________

Plasma protein levels directly affect serum oncotic pressure.

Plasma protein levels directly affect ______________.

Low TP value $\rightarrow$ Low oncotic pressure: Fluid accumulates in the interstitium, resulting in edema.

Low TP value $\rightarrow$ Low oncotic pressure: _________________, resulting in edema.

High oncotic pressure: Fluid shifts out of the interstitium back into the vasculature (blood vessels).

High oncotic pressure: Fluid shifts out of the interstitium ______________________________.

Some anesthetics (barbiturates) are highly bound to plasma proteins.

Some _________________ are highly bound to plasma proteins.

In hypoproteinemic patients, more free drug is available, effectively increasing the anesthetic dose.

In _____________ patients, more free drug is available, effectively _____________________________.

Always note protein levels when selecting an anesthetic.

Always note protein levels when ________________

Normal Total Solids Reference Ranges

• Canine: 5.5 to 7.5 g/dL

• Feline: 6.5 to 8.2 g/dL

Normal Total Solids Reference Ranges

• Canine: ___________

• Feline: ___________

Blood Glucose (BG) indicates carbohydrate (CHO) metabolism and measures the endocrine function of the pancreas.

_____________ indicates carbohydrate (CHO) metabolism and measures the endocrine function of the pancreas.

Blood Glucose (BG) indicates carbohydrate (CHO) metabolism and measures the endocrine function of the pancreas.

Blood Glucose (BG) indicates ___________________ and measures the ________________________.

Eating raises BG levels; fasting lowers them.

________ raises BG levels; _________ lowers them.

Stress elevates BG in cats.

_______ elevates BG in cats.

Check BG intraoperatively and postoperatively in juvenile and diabetic patients during long procedures.

Check BG intraoperatively and postoperatively in _________________ during ____ procedures.

Hypoglycemia Alert: BG values $< 40\text{ mg/dL}$ indicate hypoglycemia in both dogs and cats.

Hypoglycemia Alert: BG values ______________ indicate hypoglycemia in both dogs and cats.

Normal Blood Glucose Reference Ranges

• Canine: 80 to 130 mg/dL

• Feline: 70 to 180 mg/dL

Normal Blood Glucose Reference Ranges

• Canine: _____________

• Feline: _____________

Urea is a nitrogenous compound produced from amino acid breakdown in the liver.

Urea is a nitrogenous compound produced from ________________________________

Urea used to evaluate the kidneys' ability to remove nitrogenous waste.

Urea used to evaluate the kidneys' ability to _________________.

If kidneys function poorly, insufficient urea is cleared, increasing BUN levels.

If kidneys function poorly, _______________, increasing BUN levels.

BUN

Excretion pathway: Excreted by kidneys ($40\%$ reabsorbed); $<10\%$ excreted via GIT and skin.

BUN

Excretion pathway: Excreted by kidneys (_____________); _______________ via GIT and skin.

BUN concentration depends on:

1. Renal function

2. Dietary intake

3. Protein catabolism rate

BUN concentration depends on:

1. ___________

2. ___________

3. ____________

Some anesthetics are primarily metabolized by the kidneys.

Some __________ are primarily metabolized by the _______.

If renal function is questionable, select drugs not primarily metabolized by kidneys and order additional tests (e.g., urinalysis).

If renal function is questionable, select drugs not primarily metabolized by kidneys and ______________ (e.g., __________).

Normal BUN Reference Ranges

• Canine: 5 to 35 mg/dL

• Feline: 5 to 35 mg/dL

Normal BUN Reference Ranges

• Canine: ____________

• Feline: ___________

Alanine Aminotransferase (ALT) an enzyme found in high concentrations in liver cells of dogs, cats, and primates.

Alanine Aminotransferase (ALT) an enzyme found in ___________________________ of dogs, cats, and primates.

Alanine Aminotransferase (ALT)

An enzyme found in high concentrations in liver cells of dogs, cats, and primates.

Hepatocyte damage elevates blood ALT levels.

________________ elevates blood ALT levels.

Drugs like anticonvulsants and corticosteroids can also raise ALT levels.

Drugs like __________ and __________ can also raise ALT levels.

[Alanine Aminotransferase (ALT)] Used as a general hepatic screening tool (measured in U/L), though not specific to a single liver disease.

[Alanine Aminotransferase (ALT)] Used as a _____________________ (measured in U/L), though not specific to a single liver disease.

Signs of Liver Disease in Dogs

• Jaundice

• Loss of appetite

• Lethargy

• Fever

Signs of Liver Disease in Dogs

• __________

• ____________

• ________

• _______

Normal ALT Reference Ranges

• Canine: 8.2 to 109 U/L

• Feline: 25 to 97 U/L

Normal ALT Reference Ranges

• Canine: _________

• Feline: _________

Once the history, physical examination, and laboratory tests have been completed, the surgical risk can be estimated and a prognosis given

Once the _______, _____________, and__________ have been completed, the __________ can be estimated and a _________ given

An excellent prognosis should be given if the potential for complications is minimal and there is a high probability that the patient will return to normal after surgery.

An excellent prognosis should be given if the potential for ___________________ and there is a high probability that the patient will _____________________.

If there is a high probability of a good outcome but some potential for complications, a good prognosis is warranted

If there is a ___________________ but some _____________, a good prognosis is warranted

If serious complications are possible but uncommon, if recovery may be prolonged, or if the animal may not return to its presurgical function, a fair prognosis is warranted.

If serious complications are _______________, if recovery may be ________, or if the animal may not return to its presurgical function, a fair prognosis is warranted.

If the underlying disease or the surgical procedure is associated with many or severe complications (or both), if recovery is expected to be prolonged, if the likelihood of death during or after the procedure is high, or if the animal is unlikely to return to its presurgical function, a poor prognosis should be given.

If the underlying disease or the surgical procedure is associated with____________________ (or both), if recovery is expected to be prolonged, if the _____________________________, or if the animal is unlikely to return to its presurgical function, a poor prognosis should be given.

A guarded prognosis is often given when the outcome is highly variable or unknown

A guarded prognosis is often given when the __________________________