Please enable JavaScript.

Coggle requires JavaScript to display documents.

Perioperative Medicine - Coggle Diagram

- - - - ETOH
      - NASH (diabetes/obesity)
      - Viral hepatitis B & C
    - - Autoimmune
        
        PBC
        
        PSC
      - Metabolic
        
        Wilson's
        
        Haemachromatosis
        
        Alpha 1 antitrypsin
      - Toxins/drugs
      - Right heart failure
  - - - Risk of reflux due to raised intra-abdo pressure from ascities
    - - Diaphragmatic splinting, redcued FRC, V/Q mismatch
      - Effusions
      - Hepatopulmonary syndrome
        
        Pulmonary AV malformations cause R to L shunt causes platypnoea (SoB better when flat) and orthodeoxia (reduced sats sitting up)
    - - Hyperdynamic circulation
        
        High CO
        
        Low SVR
        
        Low BP
      - Portopulmonary HTN
      - Cirrhotic cardiomyopathy
      - Pericardial effusion
    - - Hepatic encephalopathy
        
        Worsened by GIB, infection, sedative drugs, hypoglycaemia, high protein intake
      - Wernicke's encephalopathy
        
        Thiamine deficiency with ETOH liver disease
    - - Delayed gastric emptying
      - Risk of varicies and erosions
    - - Anaemia
        
        Chronic blood loss from GIT
        
        Hypersplenism causing haemolysis
        
        Chronic illness
        
        Malnutrition
      - Coagulopathy
        
        Reduced factor production
      - Thrombocytopaenia and platelet dysfunction
    - - Reduced function
    - - Hepatorenal syndrome
        
        Renal dysfunction due to poor perfusion as low SVR in comparison to circulating volume
        
        Renal artery vasoconstriction via renin system and sympathetic system but perfusion remains inadequate
      - Secondary hyperaldosteronism gives ascities, effusions & oedema
    - - Depletes hepatic and muscle glycogen stores which leads to hypoglycaemia
  - - - Bilirubin
      - Albumin
      - Prothrombin time
      - Encephalopathy
      - Ascities
    - - A 100%
      - B 80%
      - C 45%
- - - - Reduce benzos/barbituates/Propofol doses
      - Reduce LAs by 25%
    - - Penicillin, cephlasporin, neostigmine, salicylates
    - - Leads to accumulation of active metabolites (m-6-g) & sedation/resp depression
    - - Prolonged block with repeat or large doses
    - - ACEis/ARBs/gentamicin/NSAIDs/contrast media
- - - - Surgical
        
        Senior team
        
        Staged surgery (laparoscopic)
        
        Meticulous haemostatsis
        
        Biological haemostasis (cellulose/fibrin glue)
        
        Cell salvage (+ leucocyte depletion filter if malignancy)
      - Anaesthetic
        
        Senior team
        
        Avoid venous congestion - relaxation/avoid high pressures/avoid hypercapnia
        
        Warming - avoid coagulopathy
        
        Flow monitoring - optimise tissue O2 delivery
        
        Regional
        
        ?Hypotensive anaesthesia
        
        POCT coagulation monitoring
      - Pharmacological
        
        Recombinant factors (VIII, IX, VIIa)
        
        Antifibrinolytics (TXA)
        
        Desmopressin (promotes vW factor release)
  - - - Advanced decision
        
        Full private discussion (no family coersion)
        
        What products can be used
        
        Own blood?
        
        Can change mind etc
      - Haem advice
        
        Epo
        
        IV iron
        
        Folate & B12
      - Stop anticoagulants & antiplatelets
      - Plan for senior teams
      - Post op plan
        
        HDU/ITU
        
        Oxygen
        
        Careful monitoring to optimise CO
        
        ?Hyperbaric O2 if Hb very low and facilities
    - - Low Reticulocyte
        
        Normocytic
        
        Renal anaemia, Anaemia of chronic disesase, Dimorphic anaemia
        
        Vitamin B12
        Folate
        LFTs
        
        Ferritin
        Transferritin
        Inflamm markers
        U&Es
        
        Macrocytic
        
        Vitamin deficiency, thyroid disease, ETOH abuse, Liver disease
        
        Microcytic
        
        IDA
      - High Reticulocyte
        
        Haemolysis
        
        Non haemolytic
        
        LDH
        Serum iron
        Free Hb
        Haptoglobin
    - - Oral iron takes 6 weeks to restore Hb
        
        Check @ 4 weeks
      - Urgent with IDA or failed oral iron
        
        IV iron
        
        Takes ~ 2 weeks to improve Hb
      - Ix cause
      - If ferritin <30
        
        IDA
        
        Give oral iron and assess
      - If ferritin 30-100 & transferrin saturation <20% or CRP >5
        
        Anaemia of chronic inflammation + IDA
        
        IV iron
      - If ferritin >100, transferrin sats <20% or CRP >5
        
        Anaemia of chronic inflamm
        
        IV iron
  - - - Reduced SvO2
      - Brain and heart cannot increase extraction
  - - - <130g/L for both sexes
      - Elective target Hb>130
  - - - B12
      - Folate
      - Iron
    - - Renal anaemia, anaemia of chronic inflammation (disease)
- - - - Minimise time
      - Avoid drains
      - Laparoscopic/minilap (colorectal)
- - - - Can make positioning for RA difficult
    - - Reduced mouth opening ?need FOI
    - - Hoarseness
        
        High risk of post op oedema & obstruction
    - - Assess RoM and symptoms when patient awake
        
        ?AFOI
    - - Limited neck extension
        
        Difficult airway
    - - Restrictive lung deficit
    - - ?Unable to use PCA
  - - - Above reasons
    - - Fibrosing alveolitis (restrictive pattern)
      - Nodules
      - Costochondral disease (reduced chest wall compliance)
    - - Pericarditis & pericardial effusions
        
        Tamponade
      - Rheumatoid nodules in heart
        
        Damage valve function
        
        Conduction issues
    - - Peripheral neuropathy
        
        Nerve entrapment
        
        Mononeuritis
        
        Drug treatment
    - - Chronic steroid use
        
        Effects glucose tolerance
        
        Immune function
        
        Fragile skin
    - - Anaemia of chronic disease
      - IDA (gastric loss from NSAIDs)
      - Thrombocytosis (inflammation)
      - DMARDs cause bone marrow suppression
    - - Friable skin
      - Fixed joint deformities
    - - Amyloidosis
      - Drug induced CKD
      - Altered drug metabolism
    - - Methotrexate induced cirrhosis
  - - - Neutropenia
      - Anaemia
        
        Should define which and correct is able
      - Platelets
        
        ?neuroaxial technique
    - - Raised U & Cr, reduced eGFR
    - - Raised Transaminases and ALP
      - Global derangement due to cirrhosis (methotrexate)
    - - Conduction disorders
      - LVH
      - 24h tape
        
        If palpitations that cannot be diagnosed on resting ECG
    - - Pleural effusions/infection/fibrotic lung disease/nodules
    - - If respiratory Sx
        
        Likely restrictive
    - - If murmur or signs/Sx of poor function
    - - If preoperative hoarseness or indication of airway issue
    - - If patient has pain or neuro Sx on flex/ext of neck
- - - - Delayed gastric emptying and pharyngeal muscle weakness
        
        ?RSI
    - - Restrictive lung defect (due to spinal deformity)
      - Central and OSA
        
        PPV
      - Aspiration and pneumonia risk
      - Exaggerated resp depressant effects of opiates & IV anaesthetics
    - - Conduction defects (risk of sudden death)
      - Cardiomyopathy
      - Hypotensive & myocardial depressant effects of anaesthetic agents increased
    - - Reduced intelligence
      - Cataracts
      - Myotonia results from shivering or sux
    - - T2DM
      - Hypothyroidism
    - - Sux causes myotonia which can make intubation difficult
      - Non depolarising agents may have prolonged action
        
        Reversal may cause myotonia
    - - Delayed stomach emptying
    - - Muscle wasting
- - - - Reduced HR reserve
      - Rapid rise in HR (especially @ low levels of work)
      - Reduced peak
      - Altered ECG with exercise
      - Reduced BP with exercise
    - - Raised ventilatory equivalent for carbon dioxide or oxygen
      - Spirometry abnormalities (reduced FVC, FEV1 or both)
      - Significantly reduced O2 sats @ peak exercise
  - - - Duker Activity Status Index
- - - - Arrhythmia
        
        Other than sinus or sinus + PACs - 5 points
        
        5 premature ventricular beats - 5 points
      - Angina
        
        Mild exertion - 10 points
        
        Any level - 20 points
      - MI
        
        Within 6m - 10 points
        
        6 months - 5 points
      - Pul oedema
        
        W/i 1 week - 10 points
        
        Any time - 5 points
      - Age>70 - 5points
      - AS
        
        <0.7cm2 - 20 points
      - Risk stratification
        
        Class 2
        
        15-30 points
        
        Intermediate risk
        
        Class 3
        
        30 points
        
        High risk
        
        Class 1
        
        0-15 points
        
        Low risk
      - Emergency surgery
        
        10 points
      - Poor general medical status
        
        5 points
- - - - Major or intermediate surgery
      - Risk of CVS cimplications
      - Combined GA and RA
      - Preop temp <36
      - ASA 2-V
- - - - 360ul whole blood n 2 heated (37degrees) cups
      - Pin attached to torsion wire immereses in each cups and rotates as blood clots
      - Transducer converts torsion of pin into TEG tracing
      - R (reaction) time
        
        Time for initiation of fibrin formation
        
        Indicates conc of soluble clotting factors in plasma
      - K time
        
        Time for amplitude of tracing to increase from 2mm to 20mm
        
        Measurement of clot kinetics
      - alpha angle
        
        Angle between tangets to tracing @ 2mm amplitude and horizontal midline
        
        Rapidity of fibrin build up and cross linking
      - MA (max amplitude)
        
        Greatest vertical width achieved (reflects strength)
        
        Number and function of platelets and fibrinogen conc
      - CL30 and CL60
        
        % reduction after 30/60min
        
        Clot stability
    - - 300ul
      - Similar heated system but pin is slowly impeeded by clotting of blood
      - CT (clotting time)
        
        Time for initiation of fibrin formation
        
        Indicates conc of soluble clotting factors in plasma
      - CFT (clot form time)
        
        Time period for the amplitude of the tracing to increase from 2 to 20 mm
        
        Measurement of clot kinetics
      - Alpha angle
        
        Angle between a tangent to the tracing at 2 mm amplitude and the horizontal midline
        
        Rapidity of fibrin build up and cross-linking
      - MCF (Max clot firmness)
        
        Greatest vertical width achieved by the tracing reflecting maximum clot strength
        
        Number and function of platelets and fibrinogen concentration
      - LY30/LY60
    - - Thrombocytopaenia
        
        K/CFT is prolonged
        
        MA/MCF is decreased
        
        R/CT value normal
      - Hypercoaguable state
        
        Decreased K time
        
        Increased alpha angle
        
        Decreased R time
        
        Increased MA
      - Blood clotting factor deficiency
        
        Increased K/CFT time
        
        Decreased alpha angle
        
        Prolonged R/CT time
        
        Decreased MA/MCF
      - Thrombolysis
        
        Normal K time
        
        Increased alpha angle
        
        Normal R time
        
        Continuously decreasing MA
- - - - Weakness (hand grip)
      - Weight loss
      - Slow performance (walk speed)
      - Low physical activity
      - Exhaustion
    - - Age related biologic vulnerability to stressors and decreased physiological reserve
      - Deficits in energy metabolism, especially the neuromuscular system
    - - Phenotype (based on physical decline)
      - Frailty index (numerous domains inc comorbidities)
    - - Clinical frailty index
        
        Electronic frailty index via systemone
      - Clinical frailty scale
        
        Edmunton fraile scale/NELA scale
      - ASA score
      - 'Tot up comorbidities'
      - First impressions - 'End of bed test' pretty good correlation
      - Colorectal - can assess sarcopenia on CTs
    - - Score can be used as screening tool
      - Higher morbidity & mortality
  - - - Reduced TBW and increased adipose -> altered Vd of drugs
      - Reduced plasma proteins affects binding
      - Increased sensitivity to CNS depressants
    - - Reduced GFR - reduced glomeruli and renal perf
    - - Cerebrovasc disease, dementia
      - Visual and hearing impairment
    - - Reduced BMR & reduced muscle mass - poorer thermoreg control
      - Increased incidence of diabetes
    - - Reduced vessel compliance -> raised SVR and LVH
      - Reduced CO (increased arm-brain time)
      - Reduced conducting cells so increased arrhythmias
      - Reduced B adrenergic Rs so reduced catecholamine response
      - Increased IHD, valvular issues
    - - Arthritis, thin skin
    - - Reduced TLC, FVC, FEV1
      - Increased RV
      - 65yrs - CC encroaches normal TV -> V/Q mismatch and reduced arterial O2 tension
    - - Edentulous, arthritis means reduced CS flexibility
- - - - Postoperative cognitive decline
    - - Delayed neurocognitive recovery
    - - Neurocognitive decline
  - - - Strong association with hypotension (aim MAP 55mmHg)