Chapters 106-114 Preoperative and Postoperative Issues Flashcards
What active cardiac conditions that in surgeries other than emergencies that mandate preoperative evaluation?
unstable angina
decompensated heart failure (systolic or diasystolic)
significant arrhythmias
severe valvular disease
What 5 clinical risk factors are independent risks for poor outcomes postoperatively?
history of ischemic heart disease prior decompenstated heart failure history of stroke OR TIA DM- insulin dependent renal insuffiency (crt >2.0)
According to ACC/AHA guidelines what is the only category of high risk surgery?
vascular surgery (aortic and PVD surgeries)
In terms of oxygen consumption, what is 1 MET?
3-5 mL/kg/min O2 consumption
Look over ACC/AHA guidlines
“patients with poor or indeterminate functional capacity fo intermediate or high risk surgery should have additional evaluation (IF IT WILL CHANGE MANAGEMENT) and if they have >1 risk factor (CAD, CHF, stroke, DM-insulin, CKD
- **need to look at the clinical risk factors to determine this-with only 1 risk factor you can proceed to surgery with heart rate control. 2 risk factors, consider preoperative evaluation IF it will change management and >3 DO IT.
Who should get beta blockers preoperatively?
1) Already on it for treatment of: angina, HTN, arrhythmicas, CHF
2) Patients undergoing vascular surgeries who are at high risk of ischemia (as determined by preop eval)
3) PROBABLY recommended for: patients intermediate to high risk factors undergoing intermediate to high risk surgeries
Time delay for elective procedures after PCI without stent? bare metal stent? DES?
without stent- 2 weeks
BMS- 4-6 weeks after dual-antiplatelet therapy
DES- at least 12 months
In-stent thrombosis mortality rate when you prematurely discontinue dual anti-platelet therapy?
20-45%
What is MOA of cocaine?
Stimulant that stimulates dopaminergic neurons and inhibits norepi reuptake
What is MOA of LSD?
It is a hallucinogen that binds to dopamine and serotonin receptors in the CNS
What is MOA of methamphetamine?
stimulation of Beta and alpha receptors in CNS and periphery with increase catecholamine release and decrease in reuptake
How is EtOH metabolized?
90% through liver, 10% through pulmonary or excreted in secretions (sweat, urine)
What is MOA of EtOH?
At low levels it binds to GABA-A receptors. At higher levels it acts as an antagonist to NMDA receptors.
What are signs and symptoms of DTs and how would you treat it (delirum tremens)
usually 24-72 hours after the last drink,
s/s= tremulousness, disorientation, hallucinations, autonomic hyperactivity (tachycardia/hypertension)
How does disulfuram work? Why is it important in perioperative period?
blocks the acetaladehyde dehydrogenase. This can block the conversion of dopamine to norepi– hypotension.
What are some anesthetic agents to consider in DDx with delayed emergence?
scopolamine/atropine==> central anticholinergic syndrome
opioids==> decrease response to hypercarbia and cause hypoventilation and decrease in clearance of gases
What are some pharmacokinetic/dyanmic factors to consider in DDx for delayed emergence?
- low cardiac output decreases profusion to kidneys/liver
- hypoproteinemia or competition of binding site with other drugs causes higher than expected drug levels
- decreased liver metabolism in extremes of age
- hypothermia causes decrease in drug metabolism and can also cause “cold narcosis” and directly suppress CNS activity
What are some endocrine disorders to consider on DDx for delayed emergence?
hypothyroid, adrenal insuffiency, hypoglycemia
What are some electrolyte abnormalities to consider in DDx of delayed emergence?
hypo-osmolarity and hyponatremia (TURP) or from SIADH
Hypercalcemia/hypocalcemia, hypermagnesium/hypomagnesemia
What are some neurologic problems to consider in DDx of delayed emergence?
global or regional ischemia; hypoxia, increased ICP, cerebral hemorrhage
