Preoperative Risk Factors

Optimize your patients' preoperative risk factors to reduce postoperative complications and improve outcomes.

Lower number of healthy red blood cells can decrease the body’s ability to transport adequate levels of oxygen to vital organs. 

There are many forms of anemia with various causes. Some forms are temporary and some are chronic. Anemia of chronic disease can occur when patients have a long-standing history of various diseases. Symptoms include fatigue, arrhythmias, weakness, shortness of breath, dizziness, along with others.


  • Optimizing anemic patients is important to avoid post-operative complications including, transfusion, hypovolemia, surgical site infection, and possible end organ damage. 
  • Patients with chronic disease can have a slightly lower hemoglobin and hematocrit than threshold values.

Surgeon Tools/Recommendations

  • Determination of the cause of anemia in a patient will drive management options.
  • Optimize patients prior to surgery if they are identified as being anemic.
Anemia Laboratory Values & Recommendations
Iron < 45 microg/DL Ferrous Sulfate: 325mg gD
Transferrin < 200 mg/DL Referral to PCP
Complete Blood Count (CBC) with Differential
-Hemoglobin: <12
-Hematocrit: <36
-Hemoglobin: <13
-Hematocrit: <39
Referral to PCP

Healthy eating, exercise, proper supplementation, avoiding harmful products/substances and managing chronic diseases (obesity, diabetes, anemia, inflammatory conditions, depression, etc.) can help to improve and sustain good nutritional status.

Studies have shown that a high percentage of patients with a (BMI) >30 are malnourished.


Patients that have been identified as obese and/or malnourished have a significantly higher complication rate, including;

  • i nfection
  • hematoma formation
  • renal 
  • cardiac complications

Surgeon Tools/Recommendations

Understanding possible treatment options is useful for collaborative efforts to optimize patient's nutritional status. Certain aspects of a patient's nutritional status can be assessed through routine blood work. 

Laboratory Parameter/Threshold for Malnutrition:
Albumin  <3.5 g/dL
Prealbumin <18 mg/dL
Total Protein <6.0 g/dL
Total Lymphocyte Count <1,500 Cells/mm3 
Iron <45 microg/dL 
Serum Transferrin <200 mg/dL
25-OH Vitamin D <30 mg/dL
Calcium <9 mg/dL
Zinc <0.66 mcg/mL

- Malnourished patients should start receiving supplementation of identified deficiencies at least 14 days prior to surgery, particularly Vitamin D and protein supplementation.

- Collaborative efforts are encouraged, including a nutritional screening checklist. 

Obesity is associated with increased risks and potential complications associated with surgery.

Accepted threshold for elective safe surgery is: (BMI) <40.


  • Poor patient outcomes
  • Major complications after surgery, include: infection, poor wound healing, difficulty breathing, deep vein thrombosis, pulmonary embolism and higher readmission rates (especially within 30-90 days of surgery).

Surgeon Tools/Recommendations

  • Establish a BMI target in your practice that can be used to help patients meet their goal.
  • Set patient-specific goals between surgeon and patient.
  • Recommend nutritional counseling and encouraging appropriate activities in elective surgical setting (see nutritional assessment)
  • Propose verbal or written contracts between patient and physician for achieving weight loss goals.

Obstructive Sleep Apnea (OSA) is the  most common type of apnea that occurs at nighttime while individuals are sleeping. OSA does not allow for normal air movement in and out of the lungs because of repeated airway collapse, which results in decreased oxygenation. 


Increases a patient’s risk of perioperative complications, especially pulmonary and cardiac complications.

Worsens chronic health conditions, including:

  • high blood pressure
  • coronary artery disease
  • congestive heart failure
  • arrhythmias
  • difficulty controlling blood sugar.

Surgeon Tools/Recommendations

Patients should undergo a sleep study prior to elective surgical procedures to further evaluate the condition and determine treatment options if there is concern for sleep apnea. 

Potential Treatment Options:

  • continue Positive Airway Pressure (CPAP)
  • oral Appliances
  • lifestyle Changes
  • weight loss
  • avoidance of alcohol and certain medications
  • quit Smoking
  • positional therapy
  • surgery

Smoking causes lung disease and contributes to fracture nonunions, wound healing, higher rates of infection and many other side effects.


Increases a person’s risk for orthopaedic injuries and diseases, such as fractures and osteoporosis.

Reduces blood supply to bones, slows production of bone-forming cells, and decreases the body’s ability to absorb calcium from the diet

Increases a patient’s risk for pulmonary complications after receiving general anesthesia

Complications include: 

  • decreased pulmonary function
  • poor tissue oxygenation
  • infection 
  • wound healing
  • cardiovascular events

Surgeon Tools/Recommendations

  • Testing patients on the day of surgery for evidence of smoking with the nicotine blood test. (i.e. cotinine test).
    • Nicotine metabolized to cotinine in liver and may remain present for up to 10 days after nicotine usage.
  • Utilize the Smoking Cessation Checklist that documents whether the patient is a current smoker or former smoker.
  • Recommend patients to quit smoking at least 4-6 weeks prior to elective surgical procedures and least 6 weeks following the surgery. 
  • Provide patients with the Quit Smoking Before Your Operation, for patients to develop an action plan to quit.

If you have any questions, please contact Meghan Eigenbrod, and Isabel S. Montoya,