2024.1 Day 1 VIVA 3

Peri-operative Medicine

A 62-year-old female has presented to the anaesthetic clinic for review. She is scheduled for a laparoscopic assisted vaginal hysterectomy in 1 month.

The clinic nurse tells you she has rheumatoid arthritis and has requested her medication list be faxed from the local GP.

What specific features from history and exam would you elicit from this patient?

Disease-specific history:

• Duration and severity of RA (years, progression pattern)

• Current disease activity (active flare vs remission)

• Systemic manifestations (cardiac, pulmonary, renal involvement)

• Cervical spine involvement (pain, radicular symptoms, mobility)

• Temporomandibular joint function (opening, pain, limitations)

• Cricoarytenoid involvement (voice changes, stridor, dysphagia)

• Functional capacity (METs assessment, ADLs, mobility aids)

Medication history:

• Current immunosuppressive regimen (specific agents, doses, duration)

• Steroid use (dose, duration, previous stress dosing requirements)

• Disease-modifying agents (DMARDs, biologics, small molecules)

• Pain management (NSAIDs, opioids, adjuncts)

• Previous anaesthetic experiences and complications

Outline your examination, highlight the findings you are expecting.

Systematic examination:

• Airway: Mallampati score, TMJ mobility, neck ROM, cervical stability

• Respiratory: Breath sounds, signs of ILD/pleural effusion

• Cardiovascular: Murmurs (valvulitis), pericardial rub, peripheral pulses

• Musculoskeletal: Hand/wrist deformities (IV access implications), spine assessment

• Neurological: Myelopathy signs, peripheral neuropathy

She reports neck stiffness. How would you evaluate for atlantoaxial instability?"

Clinical evaluation:

• History of neurological symptoms (paresthesia, weakness, incontinence)

• Pain patterns (occipital/suboccipital pain, radiating to shoulders)

• Examine for myelopathy signs (Hoffman's, hyperreflexia, clonus)

• Lhermitte's sign (electric shock with neck flexion)

• Cranial nerve examination (particularly IX-XII)

Imaging assessment:

• Flexion/extension lateral cervical X-rays (anterior atlantodental interval >3mm)

• Review any previous MRI if neurological symptoms present (cord compression, pannus formation)

• CT for bony detail if surgical intervention being considered

• Review most recent imaging (changes over time)

Anaesthetic implications:

• Avoid neck manipulation, particularly hyperextension

• Plan for manual in-line stabilization during intubation

• Consider video laryngoscopy as primary approach

• Awake fiberoptic intubation if severe instability with neurological signs

• Document neck mobility limitations clearly

Her medications include prednisolone 10mg daily, methotrexate, and infliximab. What are your concerns?

Steroid considerations:

• Long-term use (>7.5mg daily for >3 weeks) causes HPA axis suppression

• Risk of perioperative adrenal crisis without stress dosing

• Associated comorbidities: osteoporosis, poor wound healing, hyperglycemia

• Need for perioperative stress-dose steroid protocol

Methotrexate management:

• Hepatotoxicity potential (check LFTs)

• Myelosuppression risk (recent FBC, particularly WCC and platelets)

• Continue perioperatively per current guidelines (ANZCA, BSR recommendations)

• Drug interactions with NSAIDs (↑ methotrexate levels)

Infliximab (anti-TNF) issues:

• Increased infection risk (particularly respiratory)

• Timing of last dose and half-life considerations

• Impaired wound healing potential

• Potential for masking early sepsis signs (reduced inflammatory response)

• Check for TB screening prior to initiation

She reports shortness of breath climbing one flight of stairs. How would you evaluate this?

Differential diagnosis:

• RA-associated pulmonary disease:

  • Interstitial lung disease (most common)

  • Pleural effusion/thickening

  • Bronchiolitis

  • Pulmonary nodules

• Cardiac involvement (pericarditis, myocarditis, valvular disease)

• Anaemia (chronic disease and/or menorrhagia)

• Deconditioning from reduced mobility

• Drug-induced (methotrexate pneumonitis)

• Targeted investigations:

  • Baseline: CXR, spirometry, ECG, arterial blood gas

  • Advanced: DLCO (diffusion capacity), 6-minute walk test

  • HRCT chest if ILD suspected

  • Echocardiogram for cardiac evaluation

  • Complete blood count with iron studies

  • BNP if heart failure suspected

• Risk stratification:

  • Quantify functional capacity (METs)

  • Assess for supplemental oxygen requirement

  • Consider respiratory medicine consultation

  • Optimize pulmonary function preoperatively

The surgeon anticipates significant bleeding. What preparations would you make?

Preoperative preparation:

• Full blood count with platelets

• Coagulation profile including fibrinogen

• Group and save (consider crossmatch 2 units)

• Iron studies and optimisation if anaemic

• Consider postponing if platelets <80 or significant coagulopathy or transfer to a location with increased transfusion capabilities

Intraoperative strategy:

• Two large-bore IV access (16G minimum)

• Consider arterial line for beat-to-beat BP monitoring

• Tranexamic acid 1g IV at induction

• Cell salvage setup if available

• Point-of-care testing (Hb, coagulation) availability

• Blood warmer and fluid warmer preparation

Blood conservation techniques:

• Controlled hypotension if appropriate

• Careful positioning to reduce venous pressure

• Communication with surgical team about hemostasis

• Restrictive transfusion threshold (Hb <70g/L)

• Active warming to prevent hypothermia-induced coagulopathy

Detail your peri-operative management plan for this patient's medications.

Steroid management:

• Continue baseline prednisolone (10mg) on morning of surgery

• Supplemental dosing: hydrocortisone 50mg IV at induction

• Intraoperative: hydrocortisone 50mg IV q8h

• Postoperative tapering: • Day 1: hydrocortisone 50mg IV/PO TDS • Day 2: hydrocortisone 25mg TDS • Day 3: return to usual prednisolone dose

Immunomodulators:

• Methotrexate:

  • Continue weekly dosing without interruption

  • Time surgical date ideally 2-3 days from last dose

  • Monitor LFTs and FBC postoperatively

  • Ensure folate supplementation maintained

• Infliximab (anti-TNF):

  • Document date of last infusion

  • If within 2 weeks of surgery, monitor closely for infection

  • Restart postoperatively when wound healing established

  • Coordinate with rheumatologist for optimal timing

• Analgesics:

  • Discontinue NSAIDs 5 days preoperatively

  • Multimodal non-NSAID regimen:

    • Paracetamol scheduled

    • Regional anaesthesia when possible

    • Short-acting opioids as needed

• Perioperative additions:

  • VTE prophylaxis (mechanical + chemical)

  • Stress ulcer prophylaxis (PPI)

  • Continuation of essential medications (antihypertensives, etc.)

She takes regular ibuprofen 400mg TDS for joint pain. When would you stop it and why?

Cessation timing:

• Discontinue 5 days before surgery

• Resume no earlier than 24 hours post-op, guided by renal function and bleeding risk

Rationale for discontinuation:

• Reversible platelet dysfunction (inhibits thromboxane A2)

• Increased surgical bleeding risk (particularly problematic in laparoscopy)

• Potential interaction with methotrexate (increases methotrexate levels)

• Impaired renal function risk with surgical stress

• Potential interference with prostaglandin-mediated bone healing

Alternative pain management:

• Scheduled paracetamol 1g QID

• Low-dose tramadol if needed

• Topical NSAIDs for accessible joints

• Consider pregabalin 75mg BD for neuropathic component

Her preoperative Hb is 95 g/L. How would you manage this?

Further investigation:

• Iron studies (ferritin, transferrin saturation, TIBC)

• B12 and folate levels

• Reticulocyte count

• Assess for occult bleeding (menorrhagia history, fecal occult blood)

• Consider inflammatory markers (ESR/CRP) to assess disease activity

Treatment approach:

• If iron deficient: IV iron (ferric carboxymaltose 1000mg)

• If functional iron deficiency: EPO 40,000 units weekly + IV iron

• Timeline assessment: ideally treat 3-4 weeks before surgery

• Patient Blood Management principles:

  • Single Hb trigger insufficient for transfusion decision

  • Consider symptoms, comorbidities, expected blood loss

Intraoperative considerations:

• Cell salvage unavailable

• Tranexamic acid administration

• Restrictive transfusion threshold (Hb <70g/L if asymptomatic)

• Monitor for signs of tissue hypoxia (lactate, base deficit)

Postoperatively she becomes hypotensive (BP 85/40). What's your approach?

Immediate assessment:

• Full vital signs including temperature

• Clinical examination (bleeding, capillary refill, urine output)

• Assess fluid status (JVP, lung auscultation)

• Check surgical drain output

• Review recent medications

Differential diagnosis:

• Hypovolemia:

  • Surgical bleeding (most common)

  • Inadequate fluid replacement

• Adrenal crisis (missed steroid supplementation)

• Anaphylaxis (late presentation)

• Sepsis (immunocompromised status increases risk)

• Cardiac event (RA patients have increased CV risk)

• Pulmonary embolism

Initial management:

• Fluid challenge (250-500ml crystalloid)

• Hydrocortisone 100mg IV if adrenal crisis suspected

• Urgent Hb check (point-of-care)

• Surgical team review

• Vasopressors if no response to initial measures

Further investigations:

• Arterial blood gas (lactate, base deficit)

• 12-lead ECG

• Urgent FBC, coagulation studies

• Blood cultures if temperature >38°C

• Consider CT if PE suspected

The surgeon wants to delay restarting infliximab for 6 weeks. What's your advice?

Evidence-based guidance:

• ACR/BSR guidelines suggest restarting when wound healing established

• Typical delay: 10-14 days post-surgery if uncomplicated

• Six weeks is excessive and risks disease flare

Risk assessment:

• Infection risks with early restart:

  • Wound complications

  • Delayed healing

  • Masked sepsis symptoms

• Disease flare risks with prolonged withholding:

  • Increased joint damage

  • Steroid requirement increase

  • Pain management challenges

  • Reduced mobility and rehabilitation

• Recommended approach:

  • Individualised decision with rheumatologist input

  • Assess wound healing at 2 weeks post-op

  • Resume when surgical site shows good healing (typically 2-3 weeks)

  • Monitor closely for infection signs after restarting

  • Consider bridging with prednisolone increase if symptoms worsen

What specific risks does this RA patient face during positioning for laparoscopic hysterectomy?

Cervical spine risks:

• Atlantoaxial instability during positioning

• Risk of cord compression with hyperextension

• Exacerbation of pre-existing myelopathy

• Need for neutral neck position with manual stabilization

Joint-specific concerns:

• Potential for joint subluxation with manipulation

• Limited ROM causing positioning challenges

• Deformities creating pressure points (ulnar deviation, swan neck)

• Fixed flexion contractures limiting positioning options

Trendelenburg position challenges:

• Respiratory compromise (reduced FRC, already restricted lungs)

• Increased intracranial pressure with cervical spine disease

• Difficult IV access maintenance with hand deformities

• Shoulder braces potentially damaging vulnerable joints

• Lithotomy component stressing hip/knee joints

Pressure injury risks:

• Reduced tissue padding over bony prominences

• Steroid-induced skin fragility

• Peripheral neuropathy reducing sensation

• Longer positioning time due to technical challenges

Preventive measures:

• Pre-positioning joint assessment

• Additional padding at pressure points

• Careful documentation of pre-existing limitations

• Regular position checks during lengthy procedures

• Consider pressure-reducing mattress

She develops bronchospasm during pneumoperitoneum establishment. How would you manage this?

Immediate actions (0-2 minutes):

• Inform surgical team and request temporary procedure pause

• Increase FiO₂ to 100%

• Deepen anesthesia (propofol bolus 0.5mg/kg)

• Manual ventilation to assess compliance and confirm diagnosis

• Auscultate to confirm wheeze pattern/distribution

Differential diagnosis:

• Anaphylaxis (check for other signs: rash, hypotension)

• ETT malposition (endobronchial/kinked)

• Aspiration

• Pneumothorax (particularly with high airway pressures)

• Pulmonary edema

• True bronchospasm (RA-associated bronchiolitis)

Pharmacological management:

• Salbutamol 8-10 puffs via circuit MDI adaptor

• IV salbutamol 250μg slow bolus if severe

• Magnesium sulfate 50mg/kg if persistent

• Hydrocortisone 100mg IV (already part of steroid protocol)

• Consider ketamine 10-20mg if refractory

Ventilation adjustments:

• Increase I:E ratio (1:3 or 1:4)

• Reduce respiratory rate

• Accept permissive hypercapnia

• Consider requesting reduced pneumoperitoneum pressure

How would you prevent and monitor for intraoperative awareness in this patient?

Risk assessment:

• RA patients may have altered pharmacokinetics

• Cardiovascular instability may limit anesthetic depth

• Polypharmacy may affect drug metabolism

• Trendelenburg position affects drug distribution

Preventive measures:

• Adequate pre-medication (anxiolysis)

• Sufficient induction dose accounting for cardiac status

• Maintain age-adjusted MAC >0.7-0.8

• Avoid unnecessary neuromuscular blockade

• Anticipate reduced anesthetic requirements with age

• Maintain normothermia (affects drug metabolism)

Monitoring approaches:

• Processed EEG monitoring (BIS target 40-60)

• End-tidal anesthetic gas monitoring

• Clinical signs: autonomic responses

• Consider isolated forearm technique if high risk

• AEP monitoring if available for difficult cases

Documentation and follow-up:

• Detailed anesthetic record of all agents

• Record of any periods of light anesthesia

• Post-operative interview using Brice questions

• Clear explanation of monitoring used to patient

Post-op she complains of right arm numbness. What's your approach?

Immediate assessment:

• Specific distribution pattern (dermatome/peripheral nerve)

• Motor vs. sensory predominance

• Temporality (immediate vs. delayed)

• Pre-existing symptoms vs. new onset

• Associated pain characteristics

Focused examination:

• Motor testing (specific muscle groups)

• Sensory testing (light touch, pinprick, proprioception)

• Reflexes (particularly biceps, triceps)

• Vascular assessment (pulses, capillary refill)

• Comparison with contralateral side and baseline function

Likely causes in RA patient:

• Positioning-related:

  • Brachial plexus traction (especially with shoulder braces)

  • Ulnar nerve compression at elbow

  • Radial nerve compression against arm board

• Disease-related:

  • Exacerbation of pre-existing neuropathy

  • Cervical radiculopathy triggered by positioning

  • Rheumatoid vasculitis affecting vasa nervorum

• Management plan:

  • Documentation of findings

  • Distinguish surgical vs. anesthetic etiology

  • Early neurology referral if significant motor involvement

  • Expected timeframe for resolution (4-6 weeks typically)

  • Physiotherapy referral

  • EMG/NCS after 3-4 weeks if persistent

The surgeon requests deeper neuromuscular blockade for better surgical exposure. How would you respond?

RA-specific considerations:

• Potential increased sensitivity to NMBs

• Disease-associated myopathy risk

• Steroid-induced myopathy

• Drug interactions with immunosuppressants

Assessment before deepening blockade:

• Current surgical conditions (actual need vs. preference)

• Patient factors (respiratory status, anticipated emergence)

• Available monitoring (quantitative TOF)

• Reversal agent availability

Implementation approach:

• Quantitative neuromuscular monitoring mandatory

• Rocuronium preferred (reliable reversal with sugammadex)

• Titrate to PTC 1-2 for deep block

• Avoid bolus doses (incremental titration)

• Consider alternative approaches:

  • Increase pneumoperitoneum pressure slightly

  • Deepen anesthesia temporarily

  • Optimise patient position

• Reversal planning:

  • Calculate appropriate sugammadex dose (4mg/kg for deep block)

  • Ensure availability before administering additional NMBA

  • Plan for potential prolonged emergence

  • Document TOF ratio >0.9 before extubation