# 2.4 Perioperative Medicine

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<summary>PO_1.2 Outline the assessment of perioperative risk, taking into consideration the following (in accordance with the ARTS framework)1: <br>• Patient factors <br>• Anaesthesia factors <br>• Surgical factors <br>• Location <br>• Facilities <br>• Available resources <br>• Scope of practice <br>Refer to ANZCA professional document: PG07(A) Guideline on pre-anaesthesia consultation and patient preparation 2017</summary>

**Assessment of Perioperative Risk Using the ARTS Framework**

The ARTS framework provides a structured approach to perioperative risk assessment, ensuring patient safety and optimizing outcomes. This includes evaluation of **Patient Factors, Anaesthesia Factors, Surgical Factors, Location, Facilities, Available Resources, and Scope of Practice**.

### **1. Patient Factors**

Comprehensive assessment of the patient’s **medical, functional, and psychosocial** status is critical.

* **Medical History**: Co-morbidities (cardiovascular, respiratory, renal, hepatic, metabolic), prior anaesthetic complications, medication use, and allergies.
* **Functional Status**: Frailty, mobility, ASA classification.
* **Airway Assessment**: Predictors of difficult intubation, aspiration risk.
* **Psychosocial Factors**: Cognitive impairment, support systems, informed consent considerations.
* **Lifestyle Factors**: Smoking, alcohol, and substance use impact perioperative risk and should be addressed.

### **2. Anaesthesia Factors**

The choice of anaesthetic technique depends on patient status and surgical requirements:

* **Type of Anaesthesia**: General, regional, or sedation.
* **Risk Assessment**: Potential for haemodynamic instability, difficult airway, need for postoperative intensive monitoring.
* **Pre-existing Conditions**: Considerations for chronic pain, obstructive sleep apnoea, or opioid tolerance.
* **Medication Management**: Preoperative fasting, continuation or cessation of anticoagulants and other critical medications.

### **3. Surgical Factors**

Each procedure carries inherent risks influenced by:

* **Surgical Complexity**: Minor vs. major surgery, anticipated blood loss, potential for fluid shifts.
* **Duration**: Longer procedures may increase thrombotic and respiratory risks.
* **Urgency**: Elective vs. emergency surgery influences time available for optimisation.
* **Minimally Invasive vs. Open Surgery**: Implications for recovery time, postoperative pain, and resource requirements.

### **4. Location**

* **Hospital Setting**: Tertiary vs. rural or regional hospital influences available resources and patient selection.
* **Day Surgery vs. Inpatient**: Assessment of suitability for outpatient management based on procedure type and patient risk factors.
* **Transfer and Transport Considerations**: If the procedure is being performed at a facility without ICU backup, ensure appropriate transfer protocols exist.

### **5. Facilities**

* **Preoperative and Postoperative Care Availability**: PACU, HDU, ICU access if required.
* **Monitoring Equipment**: Advanced haemodynamic monitoring for high-risk patients.
* **Pain Management Resources**: Availability of regional anaesthesia, PCA pumps, or acute pain services.

### **6. Available Resources**

* **Personnel**: Appropriately trained anaesthetists, surgeons, and nursing staff.
* **Diagnostic and Laboratory Support**: Access to preoperative investigations, blood products, and imaging.
* **Postoperative Support**: Availability of allied health professionals (physiotherapists, pain specialists) for enhanced recovery programs.

### **7. Scope of Practice**

* **Clinician’s Expertise**: The anaesthetist’s and surgical team’s experience with complex cases.
* **Institutional Capabilities**: Whether the procedure aligns with hospital capabilities and policies.
* **Shared Decision-Making**: Discussing risks and benefits with patients and proceduralists.

#### **Conclusion**

The **ARTS** framework provides a structured and evidence-based approach to perioperative risk assessment, aligning with **ANZCA PG07(A) Guidelines**. Proper patient selection, risk stratification, and facility preparedness optimize surgical outcomes while ensuring patient safety.

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<summary>PO_1.3 Discuss the common conditions identified in a preoperative assessment that may require further investigation, optimisation and/or referral to a tertiary hospital for specialist anaesthetic care, for example: <br>Cardiovascular <span data-gb-custom-inline data-tag="emoji" data-code="1f393">🎓</span><a href="../../markdown/lecture-notes/fitness-for-surgery">(Notes)</a><br>• Ischaemic heart disease <br>• Hypertension <br>• Congestive cardiac failure <br>• Aortic stenosis <br>• Abnormal preoperative ECG <br>• Pacemakers/AICDs <br><br>Respiratory <br>• Chronic obstructive pulmonary disease <br>• Asthma <br>• Upper respiratory tract infection <br>• Obstructive sleep apnoea <br>• Chronic smoking Metabolic <br>• Obesity (including morbid obesity) <br><br>Endocrine <br>• Diabetes <br>• Electrolyte abnormalities <br>• Acid base abnormalities <br>• Steroid dependence</summary>

Common Preoperative Conditions Requiring Further Investigation, Optimisation, or Specialist Referral

A thorough preoperative assessment identifies conditions that may increase anaesthetic or surgical risk. Appropriate management ensures safety and improves perioperative outcomes. Below is a discussion of common conditions across various systems that may require additional care.

***

#### **1. Cardiovascular Conditions**

**A. Ischaemic Heart Disease (IHD)**

* **Concerns**: Increased risk of perioperative myocardial infarction or ischemia.
* **Management**:
  * Optimize medical therapy (e.g., beta-blockers, statins).
  * Investigate if symptomatic or high-risk (e.g., stress testing, angiography).
  * Elective surgery may require deferral for coronary revascularization.

**B. Hypertension**

* **Concerns**: Increased risk of stroke, myocardial infarction, and hemodynamic instability.
* **Management**:
  * Ensure BP is controlled (target <140/90 mmHg in most cases).
  * Postpone surgery for severe, uncontrolled hypertension (>180/110 mmHg).

**C. Congestive Cardiac Failure (CCF)**

* **Concerns**: Decompensation and fluid overload.
* **Management**:
  * Stabilize with diuretics, ACE inhibitors, and beta-blockers.
  * Assess functional status and consider echocardiography.
  * Refer severe cases to a specialist.

**D. Aortic Stenosis**

* **Concerns**: Fixed cardiac output with high risk of perioperative mortality.
* **Management**:
  * Assess severity (echocardiography).
  * Consider deferring non-urgent surgery for valve replacement if severe.

**E. Abnormal Preoperative ECG**

* **Concerns**: May indicate underlying pathology (e.g., arrhythmias, ischemia, or cardiomyopathy).
* **Management**:
  * Investigate with echocardiography or cardiology consultation.
  * Evaluate and manage arrhythmias.

**F. Pacemakers/AICDs**

* **Concerns**: Interaction with diathermy and perioperative malfunction.
* **Perioperative Assessment (** 🎓Notes)

- **Management**:
  * Identify device type and obtain device interrogation preoperatively.
  * Intraoperative programming and defibrillator deactivation as needed.

***

#### **2. Respiratory Conditions**

**A. Chronic Obstructive Pulmonary Disease (COPD)**

* **Concerns**: Risk of postoperative pulmonary complications.
* **Management**:
  * Optimize bronchodilator and steroid therapy.
  * Smoking cessation at least 4–6 weeks preoperatively.
  * Consider preoperative pulmonary function tests (PFTs).

**B. Asthma**

* **Concerns**: Perioperative bronchospasm.
* **Management**:
  * Ensure asthma is well-controlled.
  * Administer bronchodilators and steroids if needed.

**C. Upper Respiratory Tract Infection (URTI)**

* **Concerns**: Increased risk of airway reactivity and complications.
* **Management**:
  * Postpone elective surgery if febrile or symptomatic.
  * Proceed cautiously for urgent procedures.

#### **D. Obstructive Sleep Apnoea (OSA)**

* **Concerns**: Airway management difficulties and postoperative hypoventilation.
* **Management**:

  * Evaluate with STOP-BANG questionnaire or sleep study. This consists of eight yes/no questions represented by the acronym STOP-BANG:
    * **S** - **Snoring**: Do you snore loudly (loud enough to be heard through closed doors or your bed-partner elbows you for snoring at night)?
    * **T** - **Tired**: Do you often feel tired, fatigued, or sleepy during the daytime (such as falling asleep during driving or talking to someone)?
    * **O** - **Observed**: Has anyone observed you stop breathing or choking/gasping during your sleep?
    * **P** - **Pressure**: Do you have or are being treated for high blood pressure?
    * **B** - **BMI**: Body Mass Index more than 35 kg/m²?
    * **A** - **Age**: Age over 50 years old?
    * **N** - **Neck**: Neck circumference greater than 40 cm (measured around the Adam's apple)?
    * **G** - **Gender**: Male gender?

  Each "yes" answer is scored as one point. A total score of 3 or more points indicates a high risk of OSA, while fewer points suggest a low risk.

  * Use CPAP perioperatively if applicable.

**E. Chronic Smoking**

* **Concerns**: Increased pulmonary and cardiovascular risks.
* **Management**:
  * Encourage cessation 4–6 weeks preoperatively.
  * Provide nicotine replacement therapy if needed.

***

#### **3. Metabolic Conditions**

**A. Obesity (Including Morbid Obesity)**

* **Concerns**: Difficult airway, increased OSA risk, and cardiovascular strain.
* **Management**:
  * Optimize weight loss preoperatively if time allows.
  * Assess for OSA, diabetes, and cardiac function.

***

#### **4. Endocrine Conditions**

**A. Diabetes Mellitus**

* **Concerns**: Perioperative hyperglycemia, hypoglycemia, and infection risk.
* **Management**:
  * Ensure glycemic control (HbA1c <8%).
  * Adjust insulin and oral hypoglycemics perioperatively.

**B. Electrolyte Abnormalities**

* **Concerns**: Risk of arrhythmias and neuromuscular dysfunction.
* **Management**:
  * Correct potassium, sodium, calcium, and magnesium abnormalities.

**C. Acid-Base Abnormalities**

* **Concerns**: Risk of hemodynamic instability and respiratory compromise.
* **Management**:
  * Identify underlying causes (e.g., metabolic acidosis in sepsis).
  * Correct preoperatively if possible.

**D. Steroid Dependence**

* **Concerns**: Risk of adrenal insufficiency and perioperative hypotension.
* **Management**:
  * Administer stress-dose steroids perioperatively.
  * Ensure careful hemodynamic monitoring.

***

#### **Conclusion**

Preoperative conditions identified during assessment require a tailored approach to investigation, optimisation, and potential referral to specialists. Careful planning and multidisciplinary collaboration ensure perioperative safety and optimal patient outcomes.

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<summary>PO_1.4 Discuss the role of the primary care physician in optimising patients perioperatively, in their hometown, in preparation for major surgery in a larger centre.</summary>

Role of the Primary Care Physician in Perioperative Optimization for Major Surgery

The primary care physician (PCP) plays a crucial role in preparing patients for major surgery at larger centres, particularly in rural or remote settings. Their involvement ensures patients are optimised, complications are minimised, and the transition to tertiary care is seamless.

***

#### **1. Preoperative Assessment**

**A. Comprehensive Medical Evaluation**

* Identify comorbidities (e.g., diabetes, hypertension, cardiovascular or respiratory conditions).
* Conduct a thorough review of systems and physical examination.
* Assess functional status and frailty, particularly in elderly patients.

**B. Risk Stratification**

* Use validated tools (e.g., ASA classification, METs, or frailty indices) to assess perioperative risk.
* Recognize high-risk patients who may benefit from early specialist referral.

**C. Laboratory and Diagnostic Tests**

* Coordinate initial investigations as per surgical or anaesthetic recommendations:
  * Blood tests (e.g., FBC, U\&E, HbA1c).
  * ECG or echocardiography for cardiovascular evaluation.
  * Pulmonary function tests if respiratory pathology is present.

***

#### **2. Optimization of Medical Conditions**

**A. Cardiovascular Disease**

* Optimize blood pressure and heart failure management.
* Adjust anticoagulant or antiplatelet therapy in consultation with specialists.
* Address arrhythmias and refer for further testing if significant ischemic disease is suspected.

**B. Respiratory Disease**

* Improve lung function in COPD or asthma patients with bronchodilators, steroids, or smoking cessation.
* Identify and manage obstructive sleep apnoea (OSA) with CPAP therapy.

**C. Metabolic and Endocrine Disorders**

* Achieve glycemic control in diabetic patients (HbA1c < 8%).
* Correct electrolyte or acid-base imbalances.
* Address thyroid dysfunction or adrenal insufficiency.

**D. Nutritional and Functional Status**

* Initiate nutritional support for malnourished patients.
* Encourage prehabilitation, including physical activity and physiotherapy.

***

#### **3. Psychological and Social Support**

**A. Psychological Preparation**

* Address anxiety and fears related to surgery.
* Refer to counselling or mental health services if required.

**B. Social Considerations**

* Assess transportation needs and logistical arrangements for travel to the surgical centre.
* Coordinate with caregivers or family to ensure postoperative support.

***

#### **4. Coordination with Tertiary Centres**

**A. Referral Pathways**

* Ensure timely referrals with comprehensive clinical summaries, including:
  * Medical history, medications, and investigation results.
  * Details of comorbidities and optimisation measures taken.

**B. Communication with Specialists**

* Liaise with surgeons, anaesthetists, and preoperative clinics to align patient preparation with perioperative needs.

**C. Postoperative Planning**

* Facilitate discharge planning and coordinate postoperative care upon the patient’s return to the community.

***

#### **5. Health Promotion and Risk Reduction**

**A. Smoking and Alcohol**

* Counsel patients on smoking cessation (at least 4–6 weeks preoperatively).
* Address alcohol dependence or reduce intake where applicable.

**B. Medication Management**

* Review and rationalize medications:
  * Adjust dosages of anticoagulants, antihypertensives, and insulin.
  * Highlight any drug allergies or adverse reactions.

***

#### **6. Benefits of PCP Involvement**

**A. Improved Outcomes**

* Optimized patients are less likely to experience perioperative complications.
* Early detection and management of comorbidities reduce surgical cancellations and delays.

**B. Enhanced Continuity of Care**

* The PCP bridges the gap between the patient’s home environment and tertiary care, ensuring consistent medical oversight.

**C. Patient-Centered Care**

* Close patient-PCP relationships foster trust, better communication, and adherence to medical recommendations.

***

#### **7. Challenges and Strategies**

**A. Limited Resources**

* Leverage telemedicine to facilitate specialist consultations.
* Access community-based allied health services for prehabilitation and nutritional support.

**B. Geographic Barriers**

* Collaborate with health networks to coordinate transportation and accommodation near surgical centres.

***

#### **Conclusion**

The primary care physician is integral to perioperative optimization, particularly for patients in rural or remote areas. By managing comorbidities, coordinating referrals, and supporting patients holistically, PCPs ensure safer surgery and better long-term outcomes.

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<summary>PO_1.7 Discuss the continuation, cessation or recommencement of patients’ usual medications in the perioperative period</summary>

**Perioperative Management of Usual Medications**

**Continuation of Usual Medications**

* **Essential Medications to Continue**:
  * **Cardiovascular Medications**:
    * Beta-blockers: Prevent withdrawal and maintain hemodynamic stability.
    * Calcium channel blockers: Maintain blood pressure control.
    * Anti-arrhythmics (e.g., amiodarone): Avoid rebound arrhythmias.
  * **Respiratory Medications**:
    * Inhalers for asthma/COPD: Optimize lung function.
  * **Neurological Medications**:
    * Antiepileptics: Prevent seizures.
    * Anti-Parkinson’s drugs: Prevent symptom exacerbation.
  * **Hormonal Therapy**:
    * Levothyroxine: Maintain euthyroid status.
    * Insulin (modified): Prevent hyperglycemia/diabetic ketoacidosis.
  * **Psychiatric Medications**:
    * Selective serotonin reuptake inhibitors (SSRIs): Avoid withdrawal.
* **Considerations for Modification**:
  * Adjust dose/timing for medications with fasting requirements (e.g., oral hypoglycemics).
  * Switch to IV alternatives for essential medications if oral intake is restricted.

***

**Cessation of Usual Medications**

* **Medications to Stop Before Surgery**:
  * **Anticoagulants/Antiplatelets**:
    * Warfarin, DOACs, clopidogrel: Cease to reduce bleeding risk; timing depends on half-life and procedure type.
    * Exceptions: Continue in high-risk patients (e.g., mechanical valves, recent stents) with bridging therapy if necessary.
  * **Diuretics**:
    * Cease loop diuretics (e.g., furosemide) on the day of surgery to avoid hypovolemia.
  * **Non-essential Supplements**:
    * Herbal remedies, vitamins: Risk of drug interactions or bleeding (e.g., ginseng, garlic).
  * **Hypoglycemics**:
    * Cease SGLT2 inhibitors (e.g., dapagliflozin) 2–3 days preoperatively to avoid ketoacidosis risk.
* **Special Considerations**:
  * Discuss with specialists for high-risk medications (e.g., immunosuppressants, chemotherapy agents).
  * Plan cessation based on pharmacodynamics and procedure-related risks.

***

**Recommencement of Usual Medications**

* **Postoperative Timing**:
  * Resume most medications as soon as oral intake is safe.
  * Delay recommencement of anticoagulants/antiplatelets until hemostasis is assured.
  * Restart diuretics cautiously, considering fluid status.
* **Monitoring Requirements**:
  * Monitor glucose closely when restarting insulin/oral hypoglycemics.
  * Observe for bleeding or thromboembolic events when resuming anticoagulants.
* **Special Cases**:
  * Corticosteroids: Use stress-dose steroids perioperatively for patients on long-term therapy to prevent adrenal crisis.
  * Psychiatric Medications: Restart cautiously, especially if interacting with anesthetic agents.

***

**Multidisciplinary Approach**

* Collaborate with surgeons, anesthetists, and the patient’s primary physician.
* Balance risks of stopping medications (e.g., withdrawal, disease exacerbation) against perioperative risks (e.g., bleeding, hemodynamic instability).
* Individualize plans based on procedure, comorbidities, and medication profile.

This structured approach ensures optimal outcomes while minimizing perioperative risks.

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<summary>PO_1.8 Explain how emergency surgery differs from elective surgery in terms of patient pathophysiology, psychology, and preparation</summary>

**Differences Between Emergency and Elective Surgery**

**1. Pathophysiology**

* **Emergency Surgery**:
  * **Acute or Critical Illness**: Patients often present with unstable or life-threatening conditions (e.g., sepsis, trauma, ischemia).
  * **Hemodynamic Instability**: Hypovolemia, shock, or arrhythmias may be present, requiring immediate stabilization.
  * **Inflammatory Response**: Heightened systemic inflammation (e.g., cytokine storm in infection or trauma) increases perioperative risk.
  * **Coagulopathy**: Higher incidence of bleeding disorders or thrombosis due to underlying pathology or anticoagulant therapy.
* **Elective Surgery**:
  * **Chronic or Well-Controlled Conditions**: Optimised before surgery to reduce perioperative complications.
  * **Stable Physiology**: No acute derangements; better fluid, electrolyte, and metabolic balance.
  * **Planned Interventions**: Patients can undergo preoperative optimisation (e.g., anaemia correction, smoking cessation).

***

**2. Psychology**

* **Emergency Surgery**:
  * **High Anxiety and Fear**: Patients may experience shock, confusion, or fear due to sudden illness or injury.
  * **Limited Informed Consent**: Less time for discussion; decisions often made under stress or by surrogates.
  * **Psychological Trauma**: Acute stress related to the emergency and potential outcomes (e.g., disfigurement, disability).
* **Elective Surgery**:
  * **Prepared Mindset**: Patients usually have time to process and plan for surgery, reducing anxiety.
  * **Informed Consent**: Adequate time for discussion of risks, benefits, and alternatives.
  * **Preoperative Counselling**: Opportunity to address concerns, expectations, and postoperative recovery.

***

**3. Preparation**

* **Emergency Surgery**:
  * **Time Constraints**: Minimal time for preoperative optimisation; interventions are often life-saving and immediate.
  * **Limited Investigations**: Only essential tests (e.g., blood gas, hemoglobin, ECG) performed due to urgency.
  * **Intraoperative Risk Mitigation**: Focus on managing acute issues intraoperatively (e.g., fluid resuscitation, hemodynamic support).
  * **Medication Management**: Rapid cessation or adjustment of medications (e.g., anticoagulants) as needed.
* **Elective Surgery**:
  * **Comprehensive Preoperative Workup**: Detailed investigations to assess comorbidities and anaesthetic risk.
  * **Optimisation**: Time to optimise chronic conditions (e.g., hypertension, diabetes) and address modifiable risks.
  * **Preoperative Fasting and Instructions**: Adherence to guidelines for enhanced recovery protocols.
  * **Planned Resources**: Availability of specialised equipment or personnel based on the patient’s needs.

***

#### **Summary**

Emergency surgery is characterised by acute instability, urgent decision-making, and limited preparation, while elective surgery allows for optimisation, planning, and psychological readiness. The differences necessitate a tailored approach to anaesthetic and peri-operative management in each scenario.

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