Perioperative care Flashcards
Venous thromboembolism:
- Pathophysiology of VTE formation
- Risk factors
- Symptoms
- Investigations
- Management
- What timing does a PE occur after surgery
Thromboprophylaxis:
- Mechanical + contraindications
- Chemical + contraindications
- Conservative measures
- How long to carry on with thromboprophylaxis after
Venous thromboembolism:
- Pathophysiology of VTE formation: venous stasis, endothelial damage, hyper coagulable
- Risk factors: surgery prolonged, immobilisation, preg, cocp, smoking, malignancy
- Symptoms: unilat rubor callor etc, fever
- Investigations: do wells score. if <2 unlikely and do d dimer to rule out. if d dimer high then do uss in 4 hours. if >1 do uss proximal leg in 4 hours
- Management: doac (LMWH if renal <15/cancer)
- What timing does a PE occur after surgery: 10-12 days
Thromboprophylaxis:
- Mechanical + contraindications: compression stockings - not if PAD, cellulitis, oedema
- Chemical + contraindications: lmwh (not if renal impairment)
- Conservative measures: mobilise straight after, hydration, stop prothrombotic drugs
- How long to carry on with thromboprophylaxis after: compression stockings until discharge and if hip doac for 28 (14 if knee, 1 month if fragility fracture)
Anticoagulants - when to stop:
- Clopidogrel
- Antiplatelets
- Warfarin + what does INR need to be before surgery
- LMWH
- DOACs
Anticoagulants - when to stop:
- Clopidogrel: 7 days before surgery
- Antiplatelets: 5 days before
- Warfarin + what does INR need to be before surgery: 5 days before, INR <1.5 (can reverse via vit k), needs lmwh bridging if af/vte/mech hv
- LMWH: 12 hours before
- DOACs: 2 days if high risk surgery, 24 if low risk procedures
Steroids:
- Why is stopping steroids during surgery bad
- Addisonian crisis pathway
- Symptoms of crisis
- Management of steroids in surgery
Steroids:
- Why is stopping steroids during surgery bad: because high dose exogenous steroids means hpa adrenal suppression and increased stress demand during surgery means not enough cortisol so addisonian crisis
- Addisonian crisis pathway: hypoglycemia, low blood pressure, vomiting/diarrhea
- Symptoms of crisis: N+V, sweating, dizzy
- Management of steroids in surgery: so need 100mg iv hydrocortisone (if hypotensive also fludrocortisone)
Antibiotics:
- When to give prophylactic abx
- What dose
Antibiotics:
- When to give prophylactic abx: joint replacements, open fracture, gi, vascular, open urological
- What dose: IV 60 mins before surgery
Diabetes:
- Insulin and sugar during surgery
- What do we do for insulin dependant diabetics
- BGC recommendations during surgery
- Risks of diabetic patients having surgery
- What to do for medication dependant diabetics - metformin, sulphonylureas, gliflozins
Diabetes:
- Insulin and sugar during surgery: hyperglycemia and insulin resistance due to hypermetabolic stress response but then also not eating
- What do we do for insulin dependant diabetics: first in morning, reduce long acting by 20%, switch to variable rate insulin infusion
- BGC recommendations during surgery: 6-10
- Risks of diabetic patients having surgery: delayed wound healing, infection, cvs/stroke, aki, increased morbidity and mortality
- What to do for medication dependant diabetics -
metformin: if lunchtime dose omit (big lactic acidosis risk)
sulphonylureas: omit on day of surgery (or just morning dose)
gliflozins: omit on day of
Long acting insulin: reduce by 20%
Pain:
- Physiology of pain
- Signs of pain
- Complications of pain
- WHO ladder
- Patient controlled analgesia
Pain:
- Physiology of pain
- Signs of pain: inc hr, chest infections, n+v, ileus, agitation
- Complications of pain: decreased mobility, decreased oral intake, shallow breathing causing hap + atelectasis
- WHO ladder
- Patient controlled analgesia
Nutrition:
- Why are nutrition demands higher in surgery
- Complications of malnutrition
- Daily requirements
- Tools
- Nutritional options
- What is refeeding syndrome
Nutrition:
- Why are nutrition demands higher in surgery: because hypermetabolic/catabolic response
- Complications of malnutrition: impaired wound healing, infection weak muscles
- Daily requirements: 2000F, 2500M
- Tools: MUST
- Nutritional options
- What is refeeding syndrome: sudden insulin surge causes hypophosphataemia, hypokalaemia, hypomagnesia
Fluids:
- Body inputs vs outputs
- Reasons for fluid prescription (3)
- Requirements
- How to assess fluid status
- Types IV fluids
- Maintenance fluids + precautions
- Resus fluids
- Replacement fluids
Fluids:
- Body inputs vs outputs
- Reasons for fluid prescription (3): replacement, maintenance, resus
- Requirements: 25-30ml/kg/day, 50-100g glucose day, 1mmol/kg/day na/k/cl
- How to assess fluid status: skin tugor, mucus mems, urine output, bp, sunken eyes, peripheries
- Types IV fluids
- Maintenance fluids + precautions: 3 bags of 1L dextose saline + 20mmol/l kcl
- Resus fluids: 500ml bolus nacl 0.9% over 15 mins
- Replacement fluids
General anaesthetics:
- Risks
- Pre-oxygenation
- Induction steps + triad of agents
- Maintenance
- Minimum alveolar concentration + guedels signs
- Emergence
- Malignant hyperthermia
General anaesthetics:
- Risks: teeth damage, anaphylaxis, waking up, cvs events, malignant hyperthermia
- Pre-oxygenation: 3 mins to remove nitrogen so oxygen preserve in lung increasing hypoxia apnoea if difficult airway
- Induction steps + triad of agents: hypnotic agent, muscle relaxant (help intubation), analgesia (reduces dose anaesthesia needed)
- Maintenance: monitor bp, hr, oxy, capnography, eeg, mac
- Minimum alveolar concentration + guedels signs
- Emergence
- Malig hyperthermia: excessive ca release causes hyperpyrexia + muscle rigidity. Caused by suxamethonium, halothane and antipsychotics. CK in. Needs dantrolene
Regional anaesthetics:
- Advantages
- Spinal anaesthesia
- Epidural anaesthesia
- Peripheral nerve blocks
Regional anaesthetics:
- Advantages: miss GA risks, faster recovery, decreased stress response, reduced blood loss
- Spinal anaesthesia: 24G into subarach space, good for lower extremity surrgery
- Epidural anaesthesia: wider needle into epidural space, provides even prolonged relief
- Peripheral nerve blocks
Airway management:
- Oro/nasopharngeal: if reduced gcs/seizures + short procedures or to bridge for definitive airway. No nasal if basal skull fractures
- Laryngeal (igel): poor control against gastric contents. Good for day surgeries
- Endotracheal
Wound healing:
- Classifications of wounds
- Stages of wound healing (4)
- First intention vs second healing
- Factors affecting wound healing
- Complications of fibrous repair
- stages: haemostasis (platelet plug), inflammation (1-5 days, fibroblasts), regeneration/proliferation (7-56 days collagen network via fibroblasts + angiogenesis), remodelling (6 weeks-1yr, myofibroblasts)
- factors affecting healing: infection, blood supply, size, movement, malnutrition/diabetes, smoking
- complications: keloid, adhesions, wound dihiscence, loss function
Post-operative complications:
- SOB - DD + ix
- Fever - DD (4)
- Poor urine output - DD (3)
- Abdominal pain - DD (4)
- Nausea and vomiting - DD (3)
- Confusion - DD
Post-operative complications:
- SOB - atelectasis, pneumonia, pe, fat embolism ards, resp depression, mi/arrhythmia, overload - fbc/crp, abg, ecg, cxr, sputum cultures
- Fever - chest infection, cut wound infection ssi, catheter uti, collection, calves dvt, cannula infection, central line infection
day 1-2 : resp source
day 3–5: resp, uti
day 5-7: ssi, or collection
- Poor urine output: prerenal (hypovol, sepsis), aki, retention, uti, ATN (nephrotoxins) - check u+es esp hyperkal
- Abdominal pain: dishisence, ileus, ssi
- Nausea and vomiting: ileus, poor pain control
- confusion: pain, lack sleep, drugs, sepsis, renal failure, metabolic, cva
National early warning score: Monitor this post op!!
- What’s in qSOFA score
- important a-e in post op
qsofa: if equal or over 2 then sepsis (rr >21, altered mental state, sys bp <100), NEWS2 >4
a-e:
a/b- oxygen!!
c - fluids!!
e: wound, drains, catheter, pcas/epidural, tpn
Pre-operative assessment:
- When does this happen + definition
- History what to ask
- Examination
- What is ASA grading
- Investigations
- Consent
