18. Principles of Preoperative, operative, and postoperative surgery

Day of surgery (intra-op ± immediate recovery)

define the peri-operative period

reduce perioperative morbidity and mortality

what is the primary goal of pre-operative evaluation?

Cardiovascular disease (CAD, CHF, etc)

what is the number one cause of POST-operative death?

<4 METs (can't climb the stairs)

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METs = Metabolic Equivalents of Task

METs	Example activity	Surgical risk
1 MET	Eating, dressing, sitting	Very poor capacity
2–3 METs	Slow walking, light housework	Poor
≥ 4 METs ⭐	Climb 2 flights of stairs, walk uphill	Adequate
> 10 METs	Strenuous sports, running	Excellent

pre-op assessment:

number of METs indicating increased risk for peri/post-operative death

healthy patient

define ASA I patient

mild systemic disease (HTN, controlled DM)

define ASA II patient

severe systemic disease (CHF, COPD)

define an ASA III patient

severe disease that is a constant threat to life

define an ASA IV patient

Moribund, not expected to survive without surgery

define an ASA V pt

brain-dead organ donor

define an ASA VI patient

emergency surgery

An 'E' next to ASA tier indicates

Reduce ileus

Improve pain

Enhance lymphatic flow

Prevent complications (atelectasis, pneumonia)

goals of post-operative OMM

Gentle techniques only

• Myofascial release

• Lymphatic pump

• Counterstrain

OMM techniques utilized post-op

High-risk surgery

Ischemic heart disease

Heart failure

Cerebrovascular disease

Diabetes treated with insulin

Creatinine ≥2.0 mg/dL.

Revised Cardiac Risk Index assigns 1 point for each of the following

>1

an RCRI score of _____ is treated as an elevated risk for surgery

at least 14 days.

After balloon angioplasty without stent, delay elective noncardiac surgery

≥12 months if antiplatelet interruption will be needed.

chronic coronary disease: delay ≥6 months

If surgery is time-sensitive after DES, it may be considered ≥3 months after PCI if waiting is riskier than proceeding.

after stent placement for ACS, delay elective surgery

4 METs, suggests acceptable

being able to climb 2 flights of stairs is equivalent to ____ METs

COPD

Age >60

Higher ASA class

risk factors for postoperative pulmonary complications

dialyze the day before surgery

timing of dialysis in a pt before surgery

Child-Pugh staging

class A is lower risk,

B intermediate,

C very high risk

used to help stage cirrhosis severity

Bilirubin

Albumin

INR

Ascites

Encephalopathy

components of Child-Pugh staging

Continue basal insulin, but usually reduce long-acting basal insulin by about 20–25% the evening before or morning of surgery.

insulin dosing for right before surgery

possible adrenal suppression

higher infection risk

impaired wound healing.

risks of chronic steroid use

<7 g/dL in most stable hospitalized adults

recommend blood transfusion when hemoglobin is

advanced age

baseline cognitive impairment or prior delirium

frailty

sensory impairment

dehydration/electrolyte abnormalities

major risk factors for post-op delirium

hypoalbuminemia

________ is a strong marker of higher postoperative risk, though it also reflects inflammation and illness severity, not just nutrition.

prophylactic antibiotics are most clearly indicated for clean-contaminated procedures and for many clean procedures involving prosthetic material or especially high-consequence infection risk

indications for preoperative antibiotics based on type of surgery

60 minutes before incision

surgical prophylaxis of antibiotics should be given

120 minutes

vancomycin and FQs should be given within _______ of surgery

No entry into respiratory, GI, GU, or biliary tract; no inflammation

define a 'clean' wound

Controlled entry into GI/GU/respiratory/biliary tract without unusual contamination

define a 'clean-contaminated' wound

yes

is prophylaxis indicated for clean-contaminated wounds?

Major break in sterile technique, gross spillage from GI tract, fresh traumatic wounds

define a 'contaminated' wound

Established infection, perforated viscus, devitalized tissue, old traumatic wound

define a dirty/infected wound

reduce gastric volume and aspiration risk during anesthesia

what is the purpose of pre-operative fasting

allows clear liquids up to 2 hours before anesthesia, breast milk up to 4 hours, infant formula/nonhuman milk/light meal up to 6 hours, and heavier or fatty meals need longer

ASA guidlines for foods before surgery

2 hours

you can clear liquids up to ____ before surgery

new hypotension, tachycardia or bradycardia, arrhythmias, ST-segment changes, ischemic wall-motion abnormality on echo, or unexplained hemodynamic collapse

signs of MI under anesthesia

100% oxygen as needed, optimize blood pressure and oxygen delivery, reduce myocardial demand, obtain ECG/TEE if available, treat arrhythmias, and involve anesthesia/cardiology/surgery urgently

immediate management of MI under anesthesia

sudden hypoxemia, abrupt fall in end-tidal CO2, hypotension, tachycardia, bronchospasm-like physiology, right-heart strain, or cardiovascular collapse

clues of intraoperative PE

rapid rise in end-tidal CO2, tachycardia, muscle rigidity, hyperthermia later in the course, acidosis, hyperkalemia, and rhabdomyolysis after exposure to triggering anesthetics or succinylcholine

classic findings of malignant hyperthermia

stop triggering agents, call for help, hyperventilate with 100% oxygen, give IV dantrolene 2.5 mg/kg rapidly and repeat as needed, cool the patient, and treat acidosis/hyperkalemia/arrhythmias

principles of management of malignant hyperthermia

IV dantrolene 2.5 mg/kg

dantrolene dose for malignant hyperthermia

The Universal Protocol

protocol meant to prevent wrong-person, wrong-procedure, and wrong-site surgery

-Pre-procedure verification of patient, procedure, documents, imaging, implants, and consent

-Site marking when appropriate

-A final time-out immediately before starting, with active participation by the team to confirm the correct patient, site, procedure, and positioning

what are the core elements of the universal protocol