Pre-Op Risk Assessment - pg 4
CHF-HTN-VHD-Arr-PM-CKD-CVA-PAH
Pre-op 1
Testing
Pre-op 3
Treatment
Pre-op 2
Treatment
Pre-op 4
Specifics
CHF
Goldman & Detsky peri-operative risk calculators in CHF
-Anti-hypertensive medications should be continued upto the morning of surgery (given) and restarted promptly
in the post-operative period.
-In patients with grade 3 hypertension (SBP>180 mmHg and/or DBP>110 mmHg), the potential benefits of
delaying surgery to optimize the pharmacological therapy should be weighed against the risk of delaying Sx.
HTN
-In 2008, a study showed that elderly patients with CHF have higher peri-operative mortality risks and risk of
readmission than other patients including those with stable IHD admitted for same procedure. Long term outcome
of CHF with preserved EF is thought to be the same as decreased EF.
-Recommendations: use of peri-operative ASA, BB, ACE-I, Statins (and spironolactone in NYHA III)
-Aortic Stenosis:
Severe AS (<1 cm2 or <0.6 cm2/m2 of BSA) increases
peri-operative mortality. In the case of elective surgery,
the
presence of symtpoms is the key factor.
Symptoms = AVR before elective surgery
If asymptomatic going to high grade surgery,
more clinical assessment vs AVR is necessary.

-Mitral Stenosis:
No risk for non cardiac surgery if MVA>1.5 cm2
or MVA<1.5 cm2 but asymptomatic and PASP<50 mmHg
Control of heart rate is essential to avoid tachycardia which may cause pulmonary edema.



-Ventricular Arrhythmias:
.There is no evidence that PVCs and NSVT are associated with a worse post-operative prognosis.
.
Unstable SMVT should be treated with DC CV.
.
Stable SMVT can be treated with i.v amiodarone (150)
.
Unstable SPVT should be treated with DC CV. In refractory cases, BB can be helpful especially if ischemia is
suspected.
Amiodarone is reasonable in SPVT when there is no LQTS.
.
Torsade de Pointe and bradycardia, Magnesium sulfate + BB + pacing
.Isoproterenol
is recommended in patients with recurrent pause-dependent Torsades de Pointes who do
not have congenital LQTS.

-AF:
For perioperative AF, the goal of management is ventricular rate control. BB and non-dihydropyridine CCB
(
diltiazem and verapamil) are the drugs of choice for the rate control in AF. Digoxin may be used as a
1st-line drug only in patients with chronic heart failure, since it is not effective in high adrenergic states such as
surgery. BB have been shown to accelerate the conversion of AF to sinus rhythm after non-cardiac surgery.
-PM / ICD:
The electrical stimulus from electrocautery may inhibit demand PM or may reprogramme the pacemaker. It is
recommended setting the pacemaker in an
asynchronous or non-sensing mode in patients
who are pacemaker dependent and whose underlying rhythm is unreliable, and
interrogating the device
before and after surgery
to ensure appropriate programming and sensing pacing thresholds.

Interference with
ICD function can also occur during non-cardiac surgery as a result of electrical
current generated by electrocautery. The
ICD should be turned off during surgery and switched on in the
recovery phase before discharge to the ward.
Valvular Heart Disease
Arrhythmias
CKD
CVA / TIA
(antiplatelets, HTN, hyperlipidemia and glucose control)
-Contrary to common belief,
most strokes are not
related to hypoperfusion
, but occur mainly in the
presence of an intact cerebral autoregulation.
Ischaemic and embolic mechanisms are far more
common than haemodynamic compromise.
Delayed
stroke
is mainly attributed to various sources of cardiac
embolism, followed by hypercoagulability and increased
risk of thrombogenic events.

-
A review of the literature from 1970 to 2000
showed that patients with significant asympt
carotid stenosis are at high risk for fatal and
nonfatal cardiac events (8%/year), but not for
stroke (1–2%/year).




Mean PAP >25 mmHg at rest with PCWP <15 mmHg
-A mean pre-op PAP> 30 is an independent predictor
of mortality. Other predictors:
NYHA =and> II
Intermediate to high risk surgery
RV function
Duration of anesthesia

Specific drug therapy for PAH includes
CCB (only for the
few patients who are responders to the acute
vasoreactivity test),
prostanoids, endothelin
receptor antagonists, and phosphodiesterase type-
5 inhibitors.
Ideally, patients with PAH should have an
optimized treatment regimen before any surgical
intervention. It is recommended also that PAH-specific
drug therapy is
not withheld for >12 h due to
the perioperative fasting state. If progression of right
heart failure in the post-operative period, it is recomm
that the
diuretic dose be optimized and, if necessary,
that
inotropic support with dobutamine be initiated.

In the case of severe right heart failure, not responsive
to supportive therapy, the administration of temporary
inhaled
NO or i.v. epoprostenol may be indicated.