Case 3.1 – Peri-Operative Management

Preoperative Evaluation – Risk: Benefit Ratio

An accurate and complete preoperative assessment requires:

• Careful history and thorough physical examination
• Estimating ability of patient to respond to the physiologic and metabolic stress of anaesthesia and surgery
• Identify underlying medical conditions:
  • Heart disease
  • Diabetes
  • Pulmonary disease
  • Renal dysfunction
  • Hepatic dysfunction
  • Adrenal dysfunction
• Special populations: The pregnant patient; the geriatric patient
• Preoperative medication management: Anti-platelet agents, heparin, insulin, etc.
• Preoperative screening tests
• Optimising patient's pre-operative health
• Accurately assessing peri-operative risk

Specific Preoperative Management

Medication Management:

Drug Type	Comment	Preoperative	Postoperative
Beta Blocker	Abrupt discontinuation can increase risk of MI	Take as usual with sip of water a few hours before operation	Use parenteral agent postoperatively until taking P.O
Nitrates	Transdermal patches may be poorly absorbed intra-operatively	Take P.O with sip of water a few hours before operation	Use IV agent, or transdermal patches postoperatively until P.O intake resumed
Insulin	5% dextrose solutions should be given IV intra-operatively & postoperatively in patients receiving insulin; these may be run with other IV fluids	Commence an insulin-glucose infusion prior to induction of anaesthesia (or by 1000hrs at the latest)	Continue the insulin-glucose infusion for at least 24 hours postoperatively and until the patient is capable of resuming an adequate oral intake

Obesity (Body Mass Index)

BMI = weight (kg) / [height (m)]²

BMI Range	Weight Classification	Risk of Illness
<18.5	Underweight	Increased
18.5 to 24.9	Ideal weight	Normal
25.0 to 29.9	Overweight	Increased
30 to 39.9	Obese	High/Very high
40 or greater	Severely obese	Extremely high

Obesity increases perioperative risk including wound complications, DVT/PE, and anaesthetic complications.

Cardiac Risk Stratification

Cardiac Risk Score (Points System):

Points	Class (NYHA)	Potentially Fatal Cardiac Complications %	Cardiac Death %
0-6	I	0.7	0.2
6-12	II	5.0	2.0
13-25	III	11	2.0
>26	IV	22	56

Note: Potentially fatal complications include postoperative myocardial infarction, pulmonary oedema, and ventricular tachyarrhythmias

Assessment of Individual Risk Factors

Factor	Point Score
Third heart sound or raised JVP (distension)	11
MI in past 6 months	10
Rhythm other than sinus	7
>5 PVCs/min	7
Age >70	5
Emergency procedure	4
Haemodynamically significant aortic stenosis	3
Aortic, intraabdominal, intrathoracic procedure	3
Poor general health	3
Total	53

Important Considerations

• Stable versus unstable cardiac disease
• Time since cardiac event especially since AMI
• Treatment of AMI: medical vs. stent vs. CABG. Anticoagulation type and required duration
• High risk: AMI less than 2 months ago
• Low risk: AMI 12 months ago or more
• Optimise medical therapy before elective surgery

In This Particular Patient:

Features on history:

• >70 age: 5 points
• Poor health: 3 points

Features on examination: No information provided - examination findings clearly insufficient to accurately assess cardiac risk status.

Required investigations: ECG, CXR, echocardiogram (if indicated), FBC, U&E, glucose

Preoperative Diabetic Evaluation

History:

• Duration of the disease
• Diet - dietary compliance and management
• Degree of glucose control - HbA1C. How often do they check BSLs?
• Insulin requirements - type, dose, frequency
• Last insulin administration
• Peripheral symptoms - ulcers, numbness, extremity pain
• Major complications:
  • Renal (nephropathy)
  • Ocular (retinopathy)
  • Neurologic (neuropathy)
  • Cardiac (coronary artery disease)

Examination - Particular Attention to Feet:

• Minor injuries
• Evidence of poor hygiene
• Inadequate vascular supply (peripheral pulses, capillary refill)
• Ulcers
• Decreased sensory perception (monofilament testing)

Investigations:

• HbA1C - indicates glycaemic control over previous 2-3 months
• Fasting blood glucose
• U&E - assess renal function
• Urinalysis - proteinuria, glucose
• ECG - assess for silent MI or cardiac disease

Target HbA1C: Ideally <7% (53 mmol/mol), but may need to balance tight control with risk of perioperative hypoglycaemia. HbA1C >8.5% may warrant delaying elective surgery to optimise control.

Writing Medical Orders in Patient's Notes

General Considerations:

• Surgical team responsible for patient (name, position, time and date)
• Diagnosis/condition / current assessment
• Immediate plans
• Vital signs/special checks/notification parameters
• Diet/level of activity
• Special nursing care instructions:
  • Positioning
  • Wound care
  • Tubes/drains: management & care
  • Intake/output: frequency
• IV fluids
• Medications: drug, dose, route, frequency
  • Routine medications
  • Special medications
• Laboratory orders
• Special procedures/radiographs
• Miscellaneous

Sample Preoperative Notes

Component	Example for Rita
Diagnosis	Degenerative joint disease (hip)
Proposed surgery	Total Hip Replacement (avoid abbreviations) + side (left/right)
History & physical	Completed (dictated) >70 in age/generally unwell
Laboratory values	FBC (14.5/41.5%/7,500) U+E (140/4.2/26/101/10) Glu (10.5)
Imaging	CXR: NAD ECG: normal
Blood type	Group & hold (in blood bank)
Operative consent	Signed and on chart: risks, rationale, benefits, alternatives explained in detail; patient understands and agrees to proceed with the surgical plans
Signatures	Patient, witness and doctor

Important Principles:

• Write legibly or use electronic systems
• Avoid abbreviations that could be misinterpreted
• Include date, time, and signature on all entries
• Document allergies prominently
• Specify laterality for surgical procedures
• Use standard medication orders (drug, dose, route, frequency)