Periop med Flashcards
What are the 6 components of the Revised cardiac risk index (Lee Index)
High risk surgery (intraperitoneal, intrathoracic, suprainguinal vascular)
History of IHD
History of CHF
History of cerebrovascular disease (CVA or TIA)
IDDM
Pre-operative serum creat >172
Minor surgical stress (cardiac risk
Endoscopic procedures Superficial procedure Cataract Breast Ambulatory
Moderate surgical stress (cardiac risk 1-5%) includes
Intraperitoneal and intrathoracic surgery Carotid endarterectomy Head and neck surgery Orthopedic Prostate
Major surgical stress (cardiac risk >5%) includes
Aortic and other major vascular surgery
Peripheral vascular surgery
Indications for per-operative EKG
Look at number of clinical risk factors and risk of surgery;
- 1 RF + Vascular surgery OR intermediate risk
- 0 RF + vascular surgery
- Known CHD, PAD, CVA + intermediate risk procedure
- pre-op and post-op EKGs not indicated in asymptomatic ppl undergoing low risk surgery
Indications for non invasive stress testing (treadmill, Dobu stress echo, Dip Mibi)
-indicated in pts 3+ clinical risk factors AND
Risk stratification for period medicine
Emergency: life or limb threatened 1-6 weeks to allow for an evaluation
Elective procedure: delayed for up to 1 year
Clinical Risk factors
CAD
Heart Failure
CAD and perioperative mortality
- major adverse cardiac events after non cardiac surgery often associated with prior CAD
- postoperative MI rate decreased substantially as length of time from MI to operation increased; 60 days (magic number) should elapse after MI before non cardiac surgery in absence of a coronary intervention
- recent MI defined as having occurred within 6 months of non cardiac surgery was found to be independent risk factor for perioperative stroke which was associated with 8fold increase in perioperative mortality rate
- age increases risk of CAD, and thus cardiac risk period; >55
- age >65 undergoing noncardiac surgery had increase risk of stroke
- history of CVA predicts perioperative major adverse cardiac event
Heart Failure
- have higher risk of post-operative death than CAD (although emphasis often placed on CAD)
- Survival after surgery for pts with EF 30%
- it is inappropriate to assess ventricular function in pts without signs or symptoms of CV disease in preop setting (although some data to suggest that pts with a/symptomatic decr EF have increased risk of 30 day cardiovascular event rate
Indications for pre-operative ECHO
-If clinically suspect (hear murmur) moderate or greater degrees of valvular stenosis or regurgitation if
=> no ECHO within 1 year
=> significant change in clinical status or physical exam since last evaluation
Concern re AS
Does increase perioperative (30 day) mortality which increases as degree of AS increases
Consider AVR vs TAVR if eligible
If not, can proceed with surgery but ensure appropriate hemodynamic monitoring (ICU) post op
Concern re MS
Ensure appropriate hemodynamic monitoring post op
Arrhythmias (VT periop)
Ventricular premature beats and NSVT are risk factors for development of intraoperative and post op arrhythmias, not associated with increases of nonfatal MI or cardiac death in perioperative period
HOWEVER; these pts do require referral to cardiologists for further evaluation, including assessment of Ventricular function and screening for CAD
Conduction disease
- High grade conduction blocks can increase risk of complete AVB which if unanticipated may increase surgical risk and necessity temporary or permanent transvenous pacing
- pts with AV delays ex LBBB or RBBB but no history of advanced heart block or symptoms, rarely progress to complete AVB perioperatively
- presence of pre-existing conduction disorders like sinus node dysfunction and AVB requires caution of perioperative beta blockers being considered
- periop BBB and bifasciular block do not contraindicate use of bb
Perioperative arrhythmia differential
Ongoing Ischemia
Underlying cardiopulmonary disease
Drug toxicity
Metabolic derangements
Pulmonary vascular disease during perioperative period (pulmonary hypertension)
- Continue pulmonary vascular targeted therapy (PDE5 inhibitors…) unless contraindicated or not tolerated in pts with pulmonary htn undergoing non cardiac surgery
- unless the risks of delay outweight benefits of preoperative evaluation by pulmonary htn specialists before noncardiac surgery, can be beneficial to have specialists in PH come see, especially n pts with features of increased perioperative risk
MACE (what does this mean)
MI Pulmonary edema Vfib Primary cardiac arrest Complete heart block
Low risk based on RCRI score
0-1 RF LOW risk of MACE
>2 (inclusive) elevated risk MACE
minimum requirement of glucose perop to prevent catabolism
5g of glucose/hour = 100 cc D5W
When to hold Sulfonylurea pre surgery
**be aware of long half lives
HOLD AM for surgery for all
Hold 24-48 hours pre-op for long acting agents (glyburide, glimepiride, glipizide)
Note that half life increases with liver/kidney dysfunction
How to manage pts with insulin pump peri-op
Continue basal dose
How to manage pts on long acting peakless insulin peri-op (ex lantus)
Day before surgery
-decrease dose by 30%
Day of surgery
-give 70% of AM dose
How to manage pts on Intermediate acting insulin periop
Day before
-reduce night dose by 30%
Day surgery
-give 50-60% AM dose
How to manage pts on fixed combination insulin doses
Day before
-no change
Day of usrgery
-50-60% AM dose of NPH
Optimal glycemic control in hospitalized patients peri op
8-11
How to manage insulin when pt on MDI regimen (RRRN)
Calculate Total daily dose insulin (TDD)
divide by 4
Divide that dose into BID NPH
How to manage insulin when pt on mixed insulins
Calculate NPH dose given AM and PM
Give 1/2 AM NPH and 1/2 PM NPH dose
Unfractionated heparin dosing
consult thrombosis if weight >120 kg
Prophylaxis 5000 increases to Q8 if obese >120 kg
