Pre Op Jill Flashcards
goals of prep assessment
- detect unrecognized disease and risk factors
2. optimize preoperative medical condition
ASA 1 health status
healthy, non smoking
no or minimal alcohol use
ASA 2 health status
mild systemic disease (well controlled HTN, DM, stable asthma)
w/o functional limitation
social drinker, prego, obese, current smoker
ASA 3 health status
severe systemic dz/functional limitation
hx of cardiac complication COPD active hepatitis, alcohol dependence/abuse ESRD + dialysis premature infant BMI >40
ASA 4 health status
severe systemic disease w/constant threat to life
recent MI, CVA, TIA, CAD Ongoing ischemia or valve dysfunction sepsis dic ards esrd - dialysis
ASA 5 health status
moribund, not expected to survive w.o operation
ruptured aortic aneurysm
massive trauma
intracranial bleed w/mass effect
ischemic bowel in face of significant pathology
ASA 6 health status
brain dead, just going in to harvest organs
risk assessment - RCRI
6 primary indicators of cardiac complications
- high risk surgery (vascular, open peritoneal, intrathoracic procedure)
- hx of heart disease (MI, postive stress Tess, pathologic Q waves, nitrate use)
- Hx of compensated or prior HF
- hx of CVA
- DM tx with insulin
- CKD w. Cr >2 mg/dl
factors to take into account preoperative risk assessment
- exercise capacity
- age
- medications used
- obesity
- obstructive sleep apnea
- alcohol misuse
- smoking
- personal/fh of anesthetic complications
exercise functional capacity to consider pre op
poor exercise capacity = inability to perform >4 METS
strong predictor of all cause mortality, more than RCRI
age pre-op
not a significant risk factor for cardiac complications
should not be a SOLE eliminator of surgery
obstructive sleep apnea pre-op
OSA increases risk for post-operative pulmonary applications
most pts are undiagnosed
STOP BANG, high obese pts
alcohol use in pre op considerations
misuse increases risk of post op complications (esp. surgical site infection, cardiopulmonary infection)
also at risk for seizure and delirium tremens
assessing alcohol use pre op
emergent or urgent surgery will req. treatment to prevent symptoms of withdrawal
should stop drinking at least 4 weeks before physiologic abnormalities occur
AUDIT-C, CAGE, SBIRT
smoking use pre op
increased risk of ICU admission and mortality
cessation preoperatively should reduce post op issues BUT increased risk if stop <8 weeks prior to surgery
if they are current smokers at time of sx, nicotine patch should be given
when is ideal time to stop smoking prior to sx?
ideally cessation should be done months prior to surgery and not within a few weeks of tx
rare complication of anesthesia
malignant hyperthermia
must asses for family hx
occurs when pts are exposed to succinylcholine or volatile anesthetic
malignant hyperthermia epidemiology
autosomal dominant
2x more common in males (half of rxns are <19 yrs of age)
malignant hyperthermia patho
calcium accumulation occurs causing sustained muscle contraction (generates heat, consuming O2, depleting ATP)
once energy stores depleted = rhabdomyolysis of muscle = hyperkalemia and spilling myoglobin in blood
leads to CO2 production and DIC
malignant hyperthermia Clinical Presentation:
- Sustained muscular contraction, rhabdomyolysis, anaerobic metabolism and mixed metabolic and respiratory acidosis
- Early hypercarbia not amenable to increased minute volume
- Sinus tachycardia
- Masseter or generalized muscle rigidity
malignant hyperthermia management
Optimize oxygenation, end surgery
Dantrolene
ICU management, Pt counseling
Dantrolene
blocks accumulation of calcium
tx malignant hyperthermia
Indications of Preoperative Diagnostic Testing
HgB/Hct
pts age >65 undergoing major surgery
younger patients going for surgery where large blood loss is expected
Indications of Preoperative Diagnostic Testing
Cr/Chem Panel
Pts > 50, undergoing intermediate or high risk surgery
Young patients with suspected renal disease or nephrotoxic drug use
