Preo-op testing Flashcards
1
Q
joint commission requires all surgical pts to have what within 30 days of surgery?
A
- documented History and physical
2
Q
Why are preop evals so impt?
A
- 3-10% of pts undergoing surgical procedures experience serious morbidity, most of which results from cardiac, pulm, or infectious complications
3
Q
What are the goals of the preop eval?
A
- clearly defining the pt’s medical conditions
- eval the severity and stability of these conditions
- ID unrecognized comorbid disease and RFs for medical complications of surgery
- optimizing all medical conditions
- recommending periop measures to reduce the risk
- key is careful H and P (90% and 10%)
4
Q
Are routine preop tests recommended?
A
- no, overall risk of surgery is low in healthy individuals
- routine tests often lead to: false positive results, extra cost, possible delay of surgery, and medico-legal liability
- don’t perform tests unless there is a clear clinical indication
- what you order is dependent on hosp requirements and pt hx and risk of procedure
- when lab tests are felt to be necessary, it is reasonable to use results that were performed and were normal w/in the past 4 months, unless there has been a change in clinical status
5
Q
Tests recommended in certain pop groups?
A
- screening questionnaire and complete H and P
- H and H isn’t indicated unless major surgery, if older than 65, or in younger pts if significant blood loss is expected
- serum creatinine only needed if:
over 50 w/ intermediate or high risk surgery, younger w/ anticipated hypotension or nephrotoxic drugs - pregnancy testing in all women of reproductive age
- lytes, blood glucose, liver enzymes hemostasis, UA are not needed
- ECGs not needed for pts w/ low risk procedures
- CXR and PFTs not neeed unless over 50 w/ upper abdominal or thoracic surgery
6
Q
When is a preop CBC recommended?
A
- anemia is only seen in 1% of asx pts
- unanticipated WBC and platelet abnormalities are quite rare
- Hb and Hct where major blood loss is expected
- all pts older than 65 having major surgery
7
Q
What are the kidney fxn tests? When are these indicated preop? What is renal insufficiency a major predictor for?
A
- renal insufficiency is an independent RF for postop pulmonary complications and a major predictor of postop mortality
- serum creatinine most sensitive for kidney fxn (increased cardiac risk if creatinine greater than 2 mg/dL)
- rarely elevated in asx pts (0.2%), prevalence increases w/ age (9.8% ages 46-60)
- Order for pts older than 50 w/:
moderate risk surgery
anticipated hypotension
possible use of nephrotoxic med
8
Q
What is hypernatremia assoc w/? When is lytes testing routeinely recommended?
A
- unexpected abnormalities occur in less than 1%
- hypernatremia is assoc w/ an increase in periop 30 day morbidity and mortality, although the relationship b/t most lyte derangements and operative morbidity isn’t clear
- since clinicians can predict most abnormalities based on hx - lytes are NOT routinely recommended unless: on diuretics, ACEI, ARB or has known renal disease
9
Q
Blood glucose and correleation w/ surgical complications? Testing of blood glucose?
A
- not routinely recommended for healthy pts
- 25% of pts over 60 have abnormal values
- asx hyperglycemia doesn’t increase complications
- the revised cardiac risk index ID diabetes as a RF for post op cardiac complications, however only pts w/ insulin tx diabetes were at risk
- surgical pts w/ diabetes do better if glucose well controlled
10
Q
When are LFTs recommendd?
A
- not routinely recommended
- unexpected liver enzyme abnormalities are quite rare, 0.3%
- pts w/ cirrhosis and acute liver failure have more M/M - pts will have signs and sxs picked up on H and P
- pts w/ mild abnormals and no known liver disease do fine
- in Hepatitis: ALT is always greater than AST
- in cirrhosis: AST is always greater thanALT
11
Q
When is routine platelet count, PT/INR required preop?
A
- not recommended if hx, PE, and family hx don’t suggest presence of a bleeding disorder
- incidence of bleeding disorders quite rare, even so, Hx more sensitive than PT or PTT in predicting complications
- required for pts on anticoagulants and neurosurgery
- PTT = intrinsic pathway
- PT = extrinsic pathway
12
Q
When is a UA recommended?
A
- not routinely
- looking for renal disease or infection: a serum creatinine levels are more sensitive for renal disease
- UTIs have the potential to cause bacteremia and post-surgical wound infections, particularly w/ prosthetic surgery
so pts w/ positive UA and culture are tx w/ abx and proceed w/ surgery w/o delay but it is unclear whether a positive preop UA and culutre w/ subsequent abx tx prevent post-surgical infection
13
Q
When is preganncy testing recommended?
A
- for all women of reproductive age, hx not reliable
- knowledge that a woman is preg substantially changes periop management
14
Q
When is an EKG reqd preop?
A
- not routinely recommended, as it is rarely useful in absence of known cardiac disease
- abnormalities increase w/ age, rare under 45
- detecting recent MIs impt, increased M/M
- reqd for pts w/:
CAD, CHF, arrhythmias, structural heart disease, PAD or CVD, diabetes - can be considered for asx pts undergoing surgery w/ elevated risk (risk of major adverse cardiac event greater than 1%), maybe obesity
15
Q
Cardiac testing risk stratification?
A
- Cardiac risk in noncardiac surgery can approach 1% mortality: CV events leading cause of periop mortality
- multiple guidelines issued by ACC and AHA: address RFs and not recommended work-up
- eval fxnl status: Metabolic equivalents
- Revised cardiac risk index (Lee index) - 1 pt each:
high risk surgery
hx ischemic heart disease
CVD
insulin dep diabetes
Creatinine greater than 2 - resting EKG: increased risk w/ presence of Q waves or significant ST segment elevation or depression
- if serious concerns - refer to cardiologist (may need stress testing, echo, revascularization)
