PRE-OP Flashcards
(17 cards)
An elderly male arrives at the preoperative clinic for evaluation before a total knee arthroplasty. Which of the following exam findings might indicate the need for delay of his surgery for further investigation?
A. New heart murmur
B. Seasonal allergy symptoms
C. History of loud snoring from the patient
D. Severe allergic reaction in the past to morphine
A. New heart murmur
Which of the following factors indicate the need for preoperative EKG before undergoing a surgical procedure?
A. Otherwise healthy 72 year old female undergoing knee replacement secondary to degenerative arthritis
B. 70 year old male with history of controlled hypertension, DM type 2, and mild peripheral neuropathy undergoing cataract surgery
C. Otherwise healthy 50 year old man with a known systolic heart murmur and recent unchanged echocardiogram
D. 48 year old man with a 40 pack year history of smoking and mild shortness of breath after shoveling his driveway yesterday undergoing cholecystectomy
Option D presents the most compelling indication for a preoperative EKG. The new onset or worsening of a cardiac symptom (dyspnea on exertion) in a patient with significant cardiovascular risk factors (smoking history) warrants immediate cardiac evaluation, which would include an EKG, before proceeding with elective surgery. The other options have risk factors, but option D describes an unstable or new symptom that demands investigation.
To hold or not to hold on the day of surgery: Oral hypoglycemic agents
HOLD
Oral hypoglycemic agents: These are generally held on the day of surgery to avoid hypoglycemia (low blood sugar) during the perioperative period.
To hold or not to hold on the day of surgery: Beta-blockers
CONTINUE!
Beta-blockers: These are typically continued on the day of surgery. Abrupt discontinuation can lead to rebound hypertension, tachycardia, and even myocardial ischemia, especially in patients with coronary artery disease.
To hold or not to hold on the day of surgery: ACE inhibitors
HOLD!
ACE inhibitors: There’s some debate, but current guidelines often recommend holding ACE inhibitors on the day of surgery, if feasible. Continuing them can increase the risk of intraoperative hypotension (low blood pressure), particularly during induction of anesthesia.
To hold or not to hold on the day of surgery: Loop diuretics
HOLD!
Loop diuretics: These are usually held on the day of surgery to avoid excessive diuresis (fluid loss) and electrolyte imbalances, which can complicate anesthesia.
51 y/o man is scheduled for a ventral hernia repair but has an MI the week before surgery. In general, when should his surgery be performed?
a) 6 months after the MI
b) 3 months after the MI
c) 6 weeks after the MI
d) 48 to 72 hours after the MI
A. 6 months
A 60 yr old male with controlled hypertension and strangulated inguinal hernia has ASA status:
*
a) II
b) III
c) II E
d) III E
II E, E is for emergent
Describe an ASA I patient.
A normal healthy patient.
Examples: Non-smoking, no or minimal alcohol use, no systemic disease.
Describe an ASA II patient.
Examples: Mild diseases only without substantive functional limitations. Current smoker, social alcohol drinker, pregnancy, obesity (BMI 30-40 kg/m²), well-controlled diabetes mellitus or hypertension, mild lung disease.
Describe an ASA III patient.
A patient with severe systemic disease.
Examples: Substantive functional limitations; one or more moderate to severe diseases. Poorly controlled diabetes or hypertension, morbid obesity (BMI $\geq$40 kg/m²), active hepatitis, alcohol dependence/abuse, implanted pacemaker, moderate reduction of ejection fraction, end-stage renal disease (ESRD) undergoing regularly scheduled dialysis, history (>3 months) of MI, CVA, TIA, or CAD/stents.
Describe an ASA IV patient.
A patient with severe systemic disease that is a constant threat to life.
Examples: Recent (<3 months) MI, CVA, TIA, or CAD/stents, ongoing cardiac ischemia or severe valve dysfunction, severe reduction of ejection fraction, shock, sepsis, disseminated intravascular coagulation (DIC), acute respiratory distress syndrome (ARDS), or ESRD not undergoing regularly scheduled dialysis.
Describe an ASA V patient.
Describe an ASA V patient.
Back:
A moribund patient who is not expected to survive without the operation.
Examples: Ruptured abdominal/thoracic aneurysm, massive trauma, intracranial hemorrhage with mass effect, ischemic bowel in the face of significant cardiac pathology or multiple organ/system dysfunction.
Describe an ASA VI patient.
A declared brain-dead patient whose organs are being removed for donor purposes.
What does the “E” modifier mean in the ASA classification (e.g., ASA II E)?
The “E” stands for Emergency. It is appended to any ASA classification (I-VI) when the surgical procedure is an emergency. An emergency is defined as a situation where delay in treatment would significantly increase the threat to the patient’s life or body part.
When doing a routine machine check, you find that the gauge for the oxygen cylinder reads 800 p.s.i. approximately how much oxygen is in the cylinder?
ABOUT 250L
Let’s use a common example, the “E” cylinder, which is frequently used in medical settings and often has a full pressure of around 2200 p.s.i. and a full capacity of approximately 660 liters of oxygen.
Here’s how to calculate the approximate remaining volume:
Determine the percentage of oxygen remaining based on pressure:
Percentage remaining = (Current Pressure / Full Pressure) x 100%
Percentage remaining = (800 p.s.i. / 2200 p.s.i.) x 100%
Percentage remaining ≈ 0.3636 x 100% ≈ 36.4%
Calculate the approximate remaining volume in liters:
Remaining Volume = Percentage remaining (as a decimal) x Full Cylinder Volume
Remaining Volume = 0.364 x 660 liters
Remaining Volume ≈ 240 liters
So, if it’s a standard “E” cylinder that’s full at 2200 p.s.i., approximately 240 liters of oxygen would remain.
What are the speifications for a regular oxygen tank
the “E” cylinder, which is frequently used in medical settings and often has a full pressure of around 2200 p.s.i. and a full capacity of approximately 660 liters of oxygen.
