Post-op Complications Flashcards
What is the definition of an MI?
Rise and fall of troponin above 99th percentile plus one of the following: 1) symptoms 2) ECG evidence (st-t change, LBBB, new q waves) 3) imaging showing loss of viable myocardium or wall motion abnormality
What is the difference between a type 1 and 2 MI?
Type 1 - spontaneous due to an unstable coronary plaque
Type 2 - secondary to an extracardiac cause (demand ischemia)
What is the difference between STEMI and NSTEMI?
STEMI - major coronary territory or an area that has insufficient collaterals - requires urgent PCI.
NSTEMI - supplies smaller coronary territories or areas supplied by collaterals, PCI only if hemodynamically unstable or worsening symptoms
What percentage of vascular surgery patients have post-op MI (defined by elevated tropnonin?)
25%
What is unstable angina?
Recurrent or new typical chest pain with no evidence of serum troponin elevation (if trop elevated then its defined as an MI)
What are 3 types of heart failure?
1) Heart failured with reduced EF (systolic heart failure) - usually due to MI
2) Heart fialure with sustained EF (diastolic heart failure) - usually due to prolonged HTN and LVH
3) Right ventricular heart failure - usually due to LV failure and severe mitral valve disease or severe lung disease (cor pulmonale)
Which vascular procedure has the highest risk of cardiac morbidity?
Aortic surgery (EVAR 1%, Open 15%)
What is the cardiac event rate for lower extremity vascular surgery?
Depends on symptoms. CLI = 10% vs claudication 3%
What is the risk of periop cardiac morbidity after carotid surgery?
3% (1.5% with stenting)
What do pathologic q waves on an EKG represent?
Old MI, more leads = wider area of infarct
What does tall R waves and wide QRS complexes (with or without ST changes), and inverted T waves represent?
myocardial hypertrophy or dilation
What is the RCRI?
Revised cardiac risk index - 6 independent risk factors:
1-history of cardiac disease
2- history of chf
3- insulin therapy
4-chronic renal impairment
5-cerebrovascular disease
6-major surgery
According to the ACC/AHA, which patients should undergo noninvasive stress testing?
Patients with limited functional capacity < 4 METS (unable to climb 2 flights of stairs without chest pain or shortness of breath)
What did the CARP trial study?
The benefit of prophylactic PCI/CABG in patients with >70% coronary artery stenoses prior to surgery. There were no differences between patients who underwent coronary revasc compared with patients who did not.
What are 2 major limitations of the CARP trial?
1) Did not rigorously follow ACC/AHA screening and a minority of patients had evidence of severe ischemia on noninvasive testing - underpowered
2) Excluded patients wit left main disease (a population who may benefit from coronary revasc)
Should you give patients with CAD betablockade before periop?
No - POISE showed doubling of post-op strokes and cochrane review showed no clear evidence that periop prophylactic betablockade improved cardiac morbidity.
How long after PCI/stent should you delay elective non cardiac surgery?
30 days afer BMS and optimally 6 months after DES
How do you manage a suspected post-op NSTEMI?
1 - consult cardio
2- control heart rate and blood pressure with beta blockers/calcium channel blockers (if sbp > 100)
3- control pain to avoid tachycardia
4-treat tachyarrythmia (aflutter afib)
5- correct anemia, hypoxemia, follow trop
Name 5 common post-op respiratory complications
1-PE
2-pulmonary edema
3-aspiration pneumonia
4-pleural effusion
5-exacerbation of underlying disease
(ARDS, Bronchitis, resp failure, TRALI)
Name 5 patient related risk factors that put patients at higher risk of pulmonary complications
1-smoking
2-recent resp infection
3-OSA
4-COPD
5-CHF
(Functional dependence, age, ASA 2+, poorly controlled asthma)
Name 5 procedure-related risk factors for post-op pulmonary complications
1-longer than 2h
2-peri-op blood transfusion
3-type of anesthesia (local/general)
4-open surgery (over endo)
5-surgical site (aortic confers highest risk)
6- emergency surgery