What Are Surgical Criteria? Why You Must Meet Them Before Going Under the Knife | CMCS

Introduction: "Your Surgery Has Been Postponed"

Few phrases cause more anxiety for patients than being told their surgery must be delayed because they have not yet met the required "surgical criteria" (手术指标). For patients who have waited weeks or months for an operation, this can feel like an obstacle or even a sign that something has gone wrong.

In reality, the opposite is true. Surgical criteria — the set of physiological, biochemical, and clinical standards a patient must meet before undergoing an operation — exist for one reason: to protect you. Understanding what these criteria are, why they matter, and how to achieve them is an essential part of being an informed surgical patient.

What Are Surgical Criteria?

Surgical criteria (also called surgical indications and contraindications, or preoperative requirements) are the specific medical standards that a patient's body must meet for surgery to be performed safely. They fall into two broad categories:

1. Surgical Indications (手术适应证)

Indications are the clinical conditions that justify performing surgery in the first place. A patient must have a clear indication — meaning the expected benefit of surgery outweighs the risks. Examples include:

• A tumor that is resectable and surgery offers the best chance of cure
• A fractured hip that requires fixation to restore mobility
• Aortic root dilation ≥50 mm in a Marfan syndrome patient, where the risk of dissection without surgery exceeds the surgical risk
• Cervical myelopathy with progressive neurological deficits requiring urgent decompression

2. Surgical Contraindications and Preoperative Requirements (手术禁忌证 / 术前指标)

Contraindications are conditions that make surgery unsafe at a given point in time. Some are absolute (surgery cannot proceed under any circumstances until resolved) and some are relative (surgery may proceed with additional precautions or after optimization). Preoperative requirements are the specific measurable targets that must be achieved before the surgical team will proceed.

Why Do Surgical Criteria Exist? The Science of Surgical Risk

Surgery is a controlled physiological stress. Even a routine operation places significant demands on the body:

• General anesthesia suppresses breathing, blood pressure regulation, and consciousness
• Surgical incisions trigger an inflammatory response and blood loss
• The body must maintain adequate oxygen delivery to all organs throughout the procedure
• The healing process after surgery requires robust immune function, adequate nutrition, and good blood flow

When a patient's body is not in optimal condition — when blood pressure is uncontrolled, blood sugar is dangerously high, the heart is not pumping efficiently, or blood is too thin to clot — the risk of life-threatening complications during or after surgery increases dramatically. Surgical criteria exist to ensure that the patient's body can safely withstand this stress and recover effectively.

Common Surgical Criteria: What Surgeons Check

Cardiovascular (Heart and Blood Vessels)

• Blood pressure (血压): Must be controlled before elective surgery. Severely elevated blood pressure (typically >180/110 mmHg) increases the risk of stroke, heart attack, and bleeding during surgery. Target: generally <140/90 mmHg for most surgeries; stricter targets for cardiac and vascular procedures
• Heart rhythm: Uncontrolled atrial fibrillation or other arrhythmias must be managed before surgery to reduce the risk of stroke and hemodynamic instability under anesthesia
• Cardiac function (ejection fraction): Severely impaired heart function (ejection fraction <30–35%) significantly increases surgical risk; may require cardiac optimization or alternative treatment approaches
• Recent myocardial infarction (heart attack): Elective surgery is generally deferred for at least 60 days (preferably 6 months) after a heart attack, as the risk of perioperative cardiac events is markedly elevated in this window
• Anticoagulation management: Blood thinners (warfarin, NOACs, aspirin, clopidogrel) must be carefully managed before surgery — stopped far enough in advance to allow clotting, but not so far in advance as to increase clot risk in high-risk patients

Blood Sugar and Diabetes (血糖)

• Poorly controlled diabetes significantly impairs wound healing, increases infection risk, and worsens outcomes after surgery
• HbA1c target: Most surgical teams require HbA1c <8.0–8.5% (some require <7.5%) before elective surgery; very high HbA1c (>10%) is associated with dramatically increased complication rates
• Perioperative blood glucose: Target blood glucose during and after surgery is typically 6–10 mmol/L (108–180 mg/dL); both hypoglycemia and hyperglycemia are dangerous in the surgical setting
• Patients with poorly controlled diabetes may need insulin optimization, dietary adjustment, or a period of intensive glucose management before surgery can proceed

Blood Tests: The Preoperative Panel (术前血常规)

A standard preoperative blood panel assesses multiple organ systems simultaneously:

• Complete blood count (CBC 血常规):
  • Hemoglobin/hematocrit: Anemia must be corrected before major surgery; severely anemic patients cannot deliver adequate oxygen to tissues during the stress of surgery. Target hemoglobin is typically ≥80–90 g/L for most surgeries, higher for cardiac surgery (≥100 g/L)
  • White blood cell count: Active infection (elevated WBC) is a contraindication to elective surgery; the infection must be treated first
  • Platelet count: Adequate platelets are required for blood clotting; very low platelets (<50,000/μL) increase bleeding risk
• Coagulation studies (PT/INR, APTT 凝血功能): Assess the blood's ability to clot; abnormal coagulation must be corrected before surgery to prevent uncontrolled bleeding
• Liver function tests (LFTs 肝功能): The liver produces clotting factors and metabolizes anesthetic drugs; severely impaired liver function increases bleeding risk and affects drug metabolism
• Kidney function (creatinine, eGFR 肆功能): The kidneys clear anesthetic drugs and manage fluid balance; impaired kidney function requires dose adjustments and careful fluid management
• Electrolytes (sodium, potassium 电解质): Abnormal potassium levels (hypo- or hyperkalemia) can cause dangerous cardiac arrhythmias under anesthesia; must be corrected before surgery
• Albumin (白蛋白): A marker of nutritional status; low albumin indicates malnutrition, which impairs wound healing and immune function; nutritional optimization may be required before major surgery

Respiratory Function (呼吸功能)

• Patients with severe COPD, asthma, or other lung disease may require pulmonary function testing (PFTs) before major thoracic or abdominal surgery
• Active respiratory infection (pneumonia, bronchitis) is a contraindication to elective surgery; must be fully resolved first
• Smoking cessation: Ideally at least 4–8 weeks before surgery; smoking impairs wound healing, increases infection risk, and worsens respiratory function under anesthesia

Infection Control (感染控制)

• Any active infection — whether at the surgical site or elsewhere in the body — is a contraindication to elective surgery
• Introducing surgical instruments into a body with active infection dramatically increases the risk of spreading infection to the surgical site, implants (if used), or bloodstream (sepsis)
• For joint replacement surgery, even a dental infection or urinary tract infection must be treated before proceeding
• Preoperative screening for MRSA and other resistant organisms is standard at many centers

Nutritional Status (营养状态)

• Malnutrition significantly impairs wound healing, immune function, and recovery after surgery
• Severely malnourished patients (low albumin, significant unintentional weight loss) may require a period of nutritional support (oral supplements, enteral feeding, or parenteral nutrition) before major surgery
• For cancer patients who have lost significant weight due to their disease, nutritional optimization before surgery can meaningfully improve outcomes

Medication Management

• Anticoagulants and antiplatelets: Must be stopped or bridged according to specific protocols based on the drug, the surgery, and the patient's clot risk
• Diabetes medications: Metformin is typically stopped 24–48 hours before surgery (risk of lactic acidosis); insulin regimens are adjusted
• Steroids: Patients on long-term steroids require "stress dosing" to prevent adrenal crisis during surgery
• Herbal supplements: Many herbal products (ginkgo, garlic, ginseng, fish oil) affect bleeding and must be stopped 1–2 weeks before surgery

Specialty-Specific Criteria: Examples

Cardiac Surgery

Cardiac surgery has among the most stringent preoperative requirements, reflecting the high physiological demands of open-heart procedures:

• Comprehensive cardiac assessment including echocardiogram, coronary angiography, and pulmonary function
• Renal function optimization (cardiac surgery carries high risk of acute kidney injury)
• Carotid artery assessment (to reduce stroke risk during cardiopulmonary bypass)
• Dental clearance (oral bacteria can infect prosthetic valves)
• Hemoglobin optimization (cardiac surgery requires adequate oxygen-carrying capacity)

Liver Surgery

Liver resection requires careful assessment of the remaining liver's functional reserve:

• Child-Pugh score and MELD score assess overall liver function
• Future liver remnant (FLR) volume calculated from CT volumetry; must be adequate to sustain life after resection
• Portal vein embolization may be performed to stimulate growth of the future remnant before major resection
• Coagulation optimization (the liver produces clotting factors)

Orthopedic / Joint Replacement Surgery

• BMI optimization (obesity significantly increases complication rates for joint replacement)
• Skin condition assessment (skin breakdown near the surgical site increases infection risk)
• Urinary tract infection screening and treatment
• Dental clearance
• Hemoglobin optimization (joint replacement involves significant blood loss)

What Happens If Surgery Proceeds Without Meeting Criteria?

The consequences of proceeding with surgery in a patient who has not met preoperative criteria can be severe:

• Intraoperative complications: Uncontrolled bleeding, cardiac arrest, stroke, dangerous arrhythmias, respiratory failure under anesthesia
• Postoperative complications: Wound infection, poor healing, anastomotic leak (in bowel surgery), pneumonia, deep vein thrombosis, pulmonary embolism
• Organ failure: Acute kidney injury, liver failure, respiratory failure requiring prolonged ICU care
• Death: In the most severe cases, proceeding with surgery in a patient who is not ready can be fatal

This is why experienced surgical teams are firm about preoperative criteria — not to create obstacles, but to protect their patients.

How to Achieve Surgical Criteria: A Patient's Action Plan

If your surgery has been postponed because you have not yet met certain criteria, here is how to approach the optimization process:

1. Understand exactly what needs to be achieved: Ask your surgical team for specific targets — not just "your blood pressure needs to be better" but "your blood pressure needs to be below 140/90 mmHg consistently"
2. Work with the right specialists: Blood pressure optimization requires a cardiologist or internist; blood sugar control requires an endocrinologist; anemia may require a hematologist or nutritionist
3. Set a realistic timeline: Some criteria can be achieved in days (correcting electrolytes); others take weeks or months (improving HbA1c, building up hemoglobin, losing weight)
4. Follow up regularly: Repeat blood tests and assessments to confirm that targets have been reached
5. Do not stop medications without guidance: Never stop blood thinners, blood pressure medications, or other drugs without explicit instructions from your surgical team
6. Optimize lifestyle factors: Quit smoking, improve nutrition, increase physical activity within your limitations — all of these improve surgical outcomes

How CMCS Helps International Patients Navigate Surgical Criteria

For international patients traveling to Shanghai for surgery, understanding and meeting surgical criteria can be particularly challenging — especially when medical records are in a different language, when local physicians are not familiar with Chinese hospital requirements, or when the patient needs to optimize their condition before traveling.

China Medical Concierge Shanghai (CMCS) provides end-to-end support:

• Pre-arrival assessment: We review your current medical status against the specific preoperative requirements of your planned procedure and surgical team at Ruijin Hospital, Zhongshan Hospital, or other leading centers
• Gap identification: We identify which criteria you have not yet met and what needs to be done before you travel
• Specialist coordination: If optimization is needed in Shanghai (e.g., blood pressure management, anemia treatment, nutritional support), we coordinate the relevant specialist consultations
• Timeline planning: We help you plan a realistic timeline for optimization and surgery, minimizing unnecessary time away from home
• Communication bridge: We translate and communicate your preoperative requirements clearly between your home physicians and the Shanghai surgical team

For more information on how we support patients through the surgical process, see our guide: How to Get a Second Medical Opinion in Shanghai.

To discuss your case or request a consultation, contact us:

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