Detsky Cardiac Risk Calculator In Noncardiac Surgery

How does this Detsky cardiac risk calculator in noncardiac surgery work?

This health tool evaluates the risk of cardiovascular events in patients who undergo noncardiac surgery, a risk which is related to patient and surgery characteristic and is highly influenced by the existence of underlying cardiac conditions.

The Detsky cardiac risk calculator in noncardiac surgery comprises of 8 risk factors and their presence is in turn analyzed:

■ Personal history of myocardial infarction – if present, important to delineate whether it was within the latest 6 months or beyond;

■ Canadian Cardiovascular Society Angina – if angina is present, what class is it diagnosed in or whether unstable angina persisted for the past 3 months;

■ Existence of pulmonary edema in patient history – PE is one of the main post operative cardiovascular factors;

■ Diagnosis of valvular disease and possible aortic stenosis;

■ Presence of arrhythmias  – abnormal heart rhythm with premature atrial beats;

■ Assessment of general medical condition  – if any of the following dysfunctionalities is present:

PO₂ <60; PCO₂ >50; K <3; HCO₃ <20; BUN (Blood urea nitrogen) >50; Creatinine >3; elevated SGOT; chronic liver disease;

■ Type of operation  – if the surgery is elective or emergency;

■ Patient age – the cut off for increased risk is established at the age of 70 years.

Other clinical factors which are not included in the score but might prove of use during the assessment include atrial fibrillation, obsesity, diabetes mellitus or history of cerebrovascular disease.

The earlier the identification of increased risk patient groups, the better the understanding of benefits and risks of surgery. Scores such as Detsky’s allow a better cardiac risk management, especially in the perioperative evaluation and management of heart failure and myocardial infarction.

Some of the most common underlying cardiovascular diseases which pose risks in non cardiac surgeries include:

■ Peripheral artery disease;

■ Stroke;

■ Atherosclerosis;

■ Coronary artery disease.

Current medical guidelines advise the use of a preoperative risk assessment in most patients, because in some cases, undiagnosed conditions might be discovered before surgery. These assessments include personal history, physical examination and if necessary laboratory testing.

Detsky score interpretation

In order to evaluate the cardiac risk, each of the 8 items needs to be assessed and as the answers are awarded a specific number of points, a sum of points will result as score. The score range is between 0 and 85 with scores closer to 0 suggesting a lower risk and scores closer to 85.

The very high risk patients are those diagnosed with unstable angina, decompensated heart failure, high grade arrhythmias or that have had a recent myocardial infarction.

The following table presents the 4 risk groups as per the Detsky score and the associated complication risk:

References

1) Detsky AS, Abrams HB, McLaughlin JR, Drucker DJ, Sasson Z, Johnston N, Scott JG, Forbath N, Hilliard JR. (1986) Predicting cardiac complications in patients undergoing non-cardiac surgery. J Gen Intern Med; 1(4):211-9.

2) Schouten O, Bax J, Poldermans D. (2006) Assessment of cardiac risk before non‐cardiac general surgery. Heart; 92(12): 1866–1872.

3) Detsky AS, Abrams HB, Forbath N, Scott JG, Hilliard JR. (1986) Cardiac assessment for patients undergoing noncardiac surgery. A multifactorial clinical risk index. Arch Intern Med; 146(11):2131-4.

4)Goldman L, Caldera DL, Nussbaum SR, Southwick FS, Krogstad D, Murray B, Burke DS, O'Malley TA, Goroll AH, Caplan CH, Nolan J, Carabello B, Slater EE. (1977) Multifactorial index of cardiac risk in noncardiac surgical procedures. N Engl J Med; 297(16):845-50.