P R O F E S S O R & H O D : D R G A D W A L K A R S R I K A N T R

M O D E R A T O R S : D R R A V I S H A N K A R

D R V I S H W A N A T H H U G G I

P R E S E N T E R : D R D H A R A N I S H A R A D H Y A B C

FITNESS FOR NON CARDIAC SURGERY

INTRODUCTION

Fitness for non cardiac surgery requires preoperative evaluation.

Preoperative evaluation should try to answer the following questions:

1. What are the risks of surgery & general anesthesia?

2. What are the predictors of those risks?

3. Can they be reduced by preoperative measures?

4. What are the anticipated intraoperative and post operative complications?

5. What are the measures in the event of these complications?

GRADATION OF RISK OF COMMON NON CARDIAC SURGICAL PROCEDURES

Higher • Emergent major operations, especially elderly• Aortic and other non carotid major vascular surgery• Prolonged surgery associated large fluid shift and / or blood loss

Intermediate • Major thoracic surgery• Major abdominal surgery• Carotid endarterectomy• Head /neck surgery• Orthopedic surgery• Prostate surgery

Lower • Eye, skin & superficial surgery• Endoscopic procedures

EVALUATION OF ASYMPTOMATIC PATIENT

Patients without significant medical problems-especially those under age 5o- are at very low risk for perioperative complications.

Their preoperative evaluation should include a history and physical examination.

Special emphasis is placed on the assessment of functional status, exercise tolerance and cardiopulmonary symptoms and signs in an effort to reveal previously unrecognised disease that may require further evaluation prior to surgery.

A directed bleeding history should be taken to uncover coagulopathy.

Routine preoperative testing of asymptomatic healthy patients under age 50 has not been found to help predict or prevent complications.

Patients who are older than 50 years and those with risk factors for coronary artery disease should have a 12 lead ECG because evidence of clinically silent coronary artery disease should prompt further cardiac evaluation before surgery.

Patients undergoing minor or minimally invasive procedures (such as cataract surgery) may not require any routine preoperative tests.

AMERICAN SOCIETY OF ANAESTHESIOLOGIST PHYSICAL SCALE AND MORTALITY PREDICTION IN THE PERIOPERATIVE PERIOD

Class Description Mortality rate

1 Healthy individual 0.1%

2 Mild systemic disease 0.2%

3 Severe systemic disease 1.8%

4 Incapacitating systemicdisease, which is a constant threat to life

7.8%

5 Moribund patients who is likely to die with or without surgery

9.4%

CARDIAC RISK ASSESSMENT AND REDUCTION

Cardiac complications of non cardiac surgery are a major cause of perioperative morbidity and mortality

Diabetes mellitus, especially if treated with insulin, is considered a cardiovascular disease equivalent and has been shown to increase the risk of cardiac complications.

Emergency operations are also associated with greater cardiac risk.

However, emergency operations should not be delayed by extensive cardiac evaluation. Instead , patients facing emergency surgery should be medically optimized for surgery as quickly as possible and closely monitored for cardiac complications.

REVISED CARDIAC RISK INDEX

Independent Predictors of Post Operative cardiac complications

1. Intrathoracic, intraperitoneal, or infrainguinal vascular surgery

2. History of ischemic heart disease

3. History of congestive heart failure

4.Insulin treatment for diabetes mellitus

5. Serum creatinine level > 2mg/dL

6. History of cerebrovascular disease

Scoring (no. of predictors present)

Risk of major cardiac complications

None 0.4%

One 0.9%

Two 7.0%

More than two 11%

ALGORITHM FOR CARDIAC RISK ASSESSMENT

PERIOPERATIVE MEDICAL PREVENTIVE THERAPIES

β- blockers

HMG-CoA reductase inhibitors (statins)

Aspirin

Have goal of reducing perioperative adrenergic

stimulation, ischemia and inflammation which are

triggered during the perioperative period

THANK YOU

INDICATIONS FOR PROPHYLACTIC PERIOPERATIVE β BLOCADE

Strong indications Patients already taking β blocker to treat

ischemia, arrhythmia, or hypertension

Possible indications Patients with coronary artery diseaseundergoing vascular or other major surgeyPatients with multiple clinical predictors(heart failure, CKD, DM, or cerebrovascular disease) undergoing vascular or other major surgery

PREOPERATIVE PULMONARY ASSESSMENT

The guidelines from the American College of Physicians recommend the following:

1.All patients undergoing noncardiac surgery should be assessed for risk of pulmonary complications.

2.Patients undergoing emergency or prolonged (>3h) surgery; aortic aneurysm repair; vascular surgery; major abdominal, thoracic, neuro, head, or neck surgery; general anesthesia should be considered to be at higher risk for postoperative pulmonary complications.

3.Patients at higher risk of pulmonary complications should receive deep breathing exercises and/or incentive spirometry as well as selective use of nasogastric tube for postoperative nausea, vomiting, or symptomatic abdominal distension to reduce postoperative risk.

4.Routine preoperative spirometry and chest radiography are less helpful for predicting risk of postoperative pulmonary complications, but may be appropriate for patients with COPD or asthma.

5.Pulmonary artery catheterization, TPN, and Total enteral nutrition are not encouraged .

PREDISPOSING RISK FACTORS FOR PULMONARY COMPLICATIONS

1.Upper respiratory tract infection: cough, dyspnea

2.Age > 60 years

3.COPD

4. ASA Class ≥2

5.Functionally dependent

6.Congestive Heart Failure

7.Serum albumin less than 3.5g/dL

8.FEV1 less than 2L

9.MVV less than 50% of predicted

10. PEF less than 100L or 50% of predicted value

11.Pco2≥45 mmHg

12.Po2≤50 mmHg

RISK MODIFICATIONS TO REDUCE PERIOPERATIVE PULMONARY COMPLICATIONS

EVALUATION OF PATIENTS WITH LIVER DISEASE

In patients with cirrhosis, post operative complication rate correlete with the severity of liver dysfunction.

A conservative approach would be to avoid elective surgery in patients with Child- Turcotte-Pugh class C cirrhosis and pursue it with great caution in class B patients.

When surgery is elective it is prudent to attempt to reduce the severity of ascites, encephalopathy, and coagulopathy preoperatively .

FITNESS IN DIABETES MELLITUS

Many patients with DM have significant symptomatic or asymptomatic CAD and many have silent myocardial ischemia due to autonomic dysfunction.

Evidence supports intensive perioperative glycemic control to achieve near-normal glucose levels (90-110 md/dL) versus moderate glycemic control (120-200 mg/dL), using insulin infusion.

Oral hypoglycemic agents should be held on the morning of operation

Perioperative Hyperglycemia should be treated with intravenous infusion of short-acting insulin or subcutaneous sliding-scale insulin.

Patients who are diet controlled may proceed to surgery with close postoperative monitoring.

PREOPERATIVE HEMATOLOGIC EVALUATION

No data exist to identify a specific preoperative hemoglobin level that should prompt transfusion prior to surgery.

Determination of the need for preoperative transfusion in an individual patient must consider factors other than the absolute hemoglobin level, including the presence of cardiopulmonary disease, the type of surgery, and the likely severity of surgical blood loss.

Patients receiving long term oral anticoagulation are at risk of thromboembolic complication when an operation requires interruption of this therapy.

There are insufficient data to determine the excess risk incurred by holding warfarin therapy or whether this risk is mitigated by “bridging” anticoagulation, where unfractionated or low molecular heparin is administered parenterally while oral anticoagulants are held until just prior to surgery.

RECOMMENDATIONS FOR PERIOPERATIVE ANTICOAGULATION MANAGEMENT

Thromboembolic risk without Anticoagulation Recommendations

Low 1. Stop oral anticoagulation 4-5 days before surgery2. Measure INR the day before surgery to confirm

that it is less than 1.63. Resume oral anticoagulation the night of surgery, if

possible4. No bridging with parenteral anticoagulants before

or after surgery

High 1. Stop oral anticoagulation 4-5 days before surgery2. Begin therapeutic dose UFH or LMWH 2 days

after stopping oral anticoagualtion, and discontinue it 12-24 hours before surgery

3. Measure INR the day before surgery to confirm that it is less than 1.6

4. Resume oral anticoagulation the night of surgery, if possible.

5. If procedure has a low risk of bleeding, consider therapeutic dose UFH or LMWH beginning 24- 48 hours after surgery & continuing until the INR is therapeutic

NEUROLOGICAL EVALUATION

Delirium occurs in 10-15% of patients over the age of 50 years and is particularly common after hip fracture repair and aortic surgery, occurring in 30-60% of such patients.

Postoperative delirium has been associated with higher rates cardiac and pulmonary complications, poor functional recovery, an increased length of hospital stay, and an increased risk of subsequent dementia and functional decline, and increased mortality.

RISK FACTORS FOR THE DEVELOPMENT OF POSTOPERATIVE DELIRIUM

Preoperative factors

Age > 70 years

Alcohol abuse

Cognitive impairment

Poor physical function status

Markedly abnormal serum sodium, potassium, or glucose level

Aortic, thoracic, hip fracture surgery, or emergency surgery

Postoperative factors

Use of meperidine or benzodiazepines, anticholinergics, antihistaminicPostoperative hematocrit less than 30%Use of urinary catheters

FITNESS IN KIDNEY DISEASE

Although the mortality in rate for elective major surgery is low (1-4%) in patient with dialysis dependent chronic kidney disease, the risk of perioperative complications including post operative hyperkalemia, pneumonia, fluid overload and bleeding , is substantially increased.

Patients should undergo dialysis preoperatively within 24 hours before surgery and their serum electrolyte level should be measured just prior to surgery and monitored closely during the post operative period.

REFERENCES

1.Current Medical Diagnosis & Treatment- 2014

2.Harrison’s Principles of Internal Medicine-18th

edition

3. API Text Book of Medicine-9th edition

4. 2014 ACC/AHA Guidelines on Perioperative Cardiovascular evaluation and management of patients undergoing non cardiac surgery.

5. The Washington Manual of Medical Therapeutics, 34th edition