Surgical care

What is the pre assessment patients need to be considered for surgery?

• Height, weight, BP, HR, bloods

• MRSA swab (nose, back of throat, groin)

• Medical and drug history

• Explain options and procedure - pros and cons

• Sign consent forms

• Listing for surgery - can take weeks-years

What are the surgical considerations?

• Medication management in the peri-operative period

• Antibiotic prophylaxis

• Thromboprophylaxis or VTE prophylaxis

• Pain control

• Post operative nausea and vomiting

What is the peri operative period?

The time between the pre op admission to hospital and the post operative discharge back home

What is prophylaxis?

Any medical or health related procedure/medication/treatment designed to prevent diseases, infections or conditions before they happen

What is a NBM period and why is it necessary?

Nil by mouth - no eating or drinking before a surgery

• Risk of aspiration - inhalation of stomach content during surgery as it’s acidic and microbial content can cause infections

  • Pneumonia and lung damage complications

• Reduces post operative nausea

• Clear fluids can be consumed 2 hours before

• No food can be can be consumed up to 6 hours before

How is NBM weighed up against need for medications?

Medication can be given with small sips of water

• Most meds can miss a dose or two

• Prevents a relapse of chronic conditions and avoids effects of drug withdrawal

• Other routes of administration should be considered

• Would the drugs be risky for the surgery?

What drugs can cause an issue for surgical patients?

• Anticoagulants (warfarin/apixaban) - bleeding risk, may need a short acting agent (heparin/enoxaparin)

• Anti-platelets (aspirin/clopidogrel) - bleeding risk, stop a few days before surgery

• NSAIDs - stop a day before, maybe earlier for longer acting drugs

• Contraception/HRTs - VTE risk, stop 4-6 weeks before, risk to benefit is discussed

• Monoamine-oxidase inhibitors - interacts with surgical drugs, management plan with psych and anaesthetist

• Lithium - stop 24 hours before, monitor fluids and electrolytes

• ACEI/ARB - causes severe hypotension with anaesthetics, stop 24 hours before

Why is clopidogrel stopped for longer than aspirin?

Stop to allow platelets to come back and clear the drugs

• Clop is longer as it has a longer half life and more irreversible inhibition of platelet formation

What metabolic changes happen to diabetics during surgery?

Surgery = stress = metabolic changes

• Increased risk of peri-op complications - unable to compensate for hyperglycaemic (affects delayed wound healing) response to stress

• Risk of diabetic ketoacidosis T1 or non-keto hyperosmolar state T2

  • Maintain optimal blood glucose control to reduce this

• Want to reduce risk of hypo and hyperglycaemia

• Continuous variable rate intravenous insulin infusion and close monitoring of BMs and K+

How is cortisol affected from the stress of surgery?

Increased concentration (released by adrenal glands)

• Adrenal insufficiency and long term steroid use will need supplements

  • Patients with this insufficiency can lead to hypo adrenal crisis with can cause shock and circulatory collapse

• Double or triple dose of corticosteroids

  • High dose steroids can impair wound healing and increase infection risk

What changes to medication are necessary for different surgeries?

• Total thyroidectomy - stop anti-thyroid meds, start levothyroxine replacement, Ca supplements as parathyroid glands can be damaged

• Ileostomy - drug absorption is lost as a section of SI is gone, fluid and electrolyte loss, review immunosuppressant therapy (INR testing), short bowel syndrome can occur so give additional loperamide

• Below knee amputation - diabetes control, phantom pain, drug kinetics (decrease VoD)

What is a surgical site infection and risk factors?

Common but avoidable complication of any surgery

• Surgeon skill and environmental factors

• Type of operation

• Number of MOs

• Patient risk factors

How can surgery antibiotic prophylaxis risks be managed?

• MRSA screening

• Antiseptic washes

• Surgical site decontamination

• Prophylactic antibiotics

• Hospital policies

• Theatre cleaning regimen

• Sterilised equipment

• Infection control training

What are the 4 classifications of operation?

What considerations are taken when an antibiotic is indicated?

• Effective against likely agents

• Decreases antibiotic resistance

• Decreases C.difficile infection

• Decreases incidence of post op SSI

• Decreases morbidity

• Decreases mortality because of SSIs → sepsis

• Decreases hospital stay

• Adequate tissue levels

• Cheaper and less side effects

What is Venous thromboembolism (VTE)?

Prevention of deep vein thrombosis and pulmonary embolism

• DVT - clot forms in deep vein of legs (can be in arms). Can be asymptomatic until too late (shortness of breath)

• PE - artery in lung is blocked by a clot

What are the risk factors of Venous thromboembolism (VTE)?

• Hydration

• Anaesthetic choice

• Positioning during surgery

• Length of surgery

• Immobility post op

• Drugs - OCP/HRT

• Obesity

• Previous history of DVT/PE

• Other medical conditions

How much of a risk is not having any prophylaxis?

VTE would happen in these percentages of surgery

• 20% of major general surgery

• 40% of major orthopedic surgery

• 44% of elective hip surgery

• 10-20% of medical patients

Need to consider patient risk factors and surgical risk to decide appropriate thromboprophylaxis. Has to balance against risk of bleeding

How is VTE risk managed?

• Mechanical prophylaxis - graduated elastic compression socks, reduce venous stasis

• Pharmacological prophylaxis - injections of heparin/fondaparinux, oral anticoagulants, aspirin, side effects and contraindications

• Mobilisations/leg exercises

• Hydration

What surgical factors influence pain?

• Intraoperative pain management

• Nature and duration of surgery

• Site and size of infusion

• Extent of surgical trauma

• Patient factors

How is it known which analgesic to pick?

• Mild to moderate pain - strong opioid ± nonopioid ± adjuvant

• Moderate to severe pain - weak opioid and/or nonopioid codeine/tramadol ± adjuvant

• Severe pain - non opioid codeine/tramadol/NSAID ± adjuvant

What are the opioids, adjuvants and others to choose from?

• Opioids - morphine, oxycodone or dihydrocodeine

• Adjuvants - paracetamol regularly ± NSAID

• Other - PCA, epidural, nerve blockers, ketamine, gabapenguin

What is patient controlled analgesia (PCA) and how does it work?

Intravenous opiate - morphine in infusion pump

• Patient titrates analgesia for breakthrough pain

• Limits set for dose and lockout to prevent overdose

• Can set continuous background if necessary

• Records 24 hour opiate use

• As pain decreases can switch to oral, stop oral opioids if still on PCA

• Monitor opiate toxicity (sedation, respiratory depression, pinpoint pupils) and pain score

How does the epidural work?

• Local anaesthetic ± opiate in the space outside the dura (eg bupivacaine + fentanyl)

• Drugs can selectively block sensation without shutting off motor function entirely

• Level of analgesia depends on where the catheter is inserted

• Bonus with continuous background or as a PCA

What are the potential side effects of epidural analgesia?

• Individual drug side effects

• Hypotension

• Bradycardia

• Haematoma risk with heparins - note timings

What are the consequences of post op nausea and vomiting?

• Potential for aspiration of vomit

• Delayed administration of opiates

• Would disruption after abdominal surgery

• Dehydration/electrolyte disturbances

• Delay in mobilisation and recovery

• Patient discomfort, distress and fear

20-30% of patients experience it

What are the risk factors of PONV?

• Patient - age, gender, anxiety, history of PONV

• Surgery - GI surgery, long surgeries

• Anaesthestic - general has a higher risk than local

• Post op

Cyclosine are first line agents used

What advice are patients given to prepare for knee replacement surgery?

• Losing weight, watching her diet to reduce strain

• Moving ankle, leg, knee exercises for circulation, pain and discomfort

• Making sure home environment is easy to live in after surgery

• Remember to bring in medication

For a patient having knee replacement surgery what does NICE say about reducing venous thromboembolism risk?

• Offer VTE prophylaxis to people undergoing elective knee replacement surgery whose VTE risk outweighs their risk of bleeding

  • Aspirin (75 mg or 150 mg) for 14 days.

  • LMWH (Low molecular weight heparin) for 14 days combined with anti-embolism stockings until discharge.

  • Rivaroxaban

What is a common LMWH given to reduce VTE risk?, include dose

Enoxaparin sodium

• 40mg injection to be given 12 hours before surgery then 40mg every 24 hours

How can pain be managed after knee surgery?

Manage pain so she’s not in bed all day - reduces risk of VTE

• Oral medications

• Paracetamol

• NSAIDs

• Opioids for moderate to severe pain

What surgery/medication side effects can happen and how can it be fixed?

• Side effect of opioids is constipation - prescribe laxative

• Respiratory depression as well - prescribe naloxone

• Post op nausea - prescribe cyclizine

• Infections after surgery - prescribe antibiotics