Copd clinical cases for anesthesia


Published on

lecture on how can anesthetist deal with Chronic obstructive lung disease during anesthesia.

Published in: Education, Health & Medicine
1 Like
  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Copd clinical cases for anesthesia

  1. 1. Chronic obstructive airways disease Clinical cases Dr Abdullah Alsailamy
  2. 2. A 75-year-old man w ith chronic obstructive airways d isease requires a transurethral resection of the prostate. Out line the advantages and disadvantages of subarachno id anaesthesia for this patient. This question does not require a general generic discussion of the advantages and disadvantages of spinal anaesthesia. You should focus your answer round the fact that the patient h,,15 chronic obstructive pulmonary disease. Both the surgical condi- tion and the medical disease arc common. Introduct ion Transurethral urology lends itself well to regional anaesthesia, but despite this not all urological surgeons share the anaesthetlsts' enthusiasm and if given a choice prefer general anaesthesia. Coexisting pulmonary disease makes the arguments in favour of subarachnoid or extrad ural analgesia more persuasive, although there remain some disadvantages. • In the patient with COPD: main advantages lie in avoidance of general anaesthesia Full control of the airway and breathing. No airway instrumentation with the attendant risk of provoking bronchoconstriction. No risk of barotrauma (pneumothorax) with IPPV. - No respiratory depression. No difficulty in resum ption of adequate spontaneous ventilation. - Lower risk of postoperative chest infection . • Advantages specific for TURP - Earlier and easier detection of the TURP synd rome. • Generic advantages of the technique - Possible lower risk of venous embolism. Good postoperative analgesia (although pain after TURP is not usually severe). • In the patient with COPD the disadvantages of spinal anaesthesia include: Respiratory compromise if the block spreads to involve the intercostal muscles. Patients with COPD may find it difficult to lie flat. Persistent coughing will interfere with surgery. C":I'I1l'riC disadvantages of the technique: I lypotension (in an elderly age group). Unsuitable for the restless or uncooperati ve patient. Stuno suggestion that there is increased fibrinolysis under subarachnoid block (SAIl). Rlsk of postdural puncture headache (small). M rklng points: It helps if th e candidate gives some impression of having i tlrll l l,,, l ,. d th ~. o;p, I"nn n it inn'" Ynlll",jl l nnt n ", ,,,,,, th i o; n l lPd in n Ilnlr..;", un l l f nrl l ( nn
  3. 3. How would you assess a patient with chronic obstructive pulmonary disease (COPO) who presents for laparotomy? What a re the major perioperative risks and how may they be reduced? A patient with severe COPD can present significant anaesthetic challenges, the main one being how to ensure that they may be kept off a ventilator and out of an inten- sive care unit. COPD is a spectrum of disease and the question is assessing your knowledge of the condition and your judgement in its management. Introduction The cardinal feature of chronic obstructive pulmonary d isease is increased airways resistance to flow (hence the alternative title of chronic obstructive airways disease). COPD is characterised by a disease spectrum that ranges from chronic bronchitis which limits activity only mildly, to severe and incapacitating emphysema. Preoperative assessment: history • Exercise tolerance (stair climbing is a more reliable ind icator than walking on the flat). • Dyspnoea (on severe, moderate or minimal exertion, or at rest). • Sputum and cough:chronic, or is there evidence of acute intercurrent infection? • Medication: steroids, bronchodilators, domiciliary oxygen. • Hospital and especially lTV ad missions for exacerbations. • Smoking history. Preoperative assessment: signs • Body habitus: are they barrel-chested, plethoric, asthenic? • Dyspnoea: are they able to talk in sentences at rest? • Respiratory pattern: is there 'fish mouth' breathing. use of accessory muscles? • Auscultation:are there wheezes , crackles, adventitious sounds? • Right heart failu re: is there peripheral oedema, jugu lar venous distension, hepatomegaly? Preoperative assessment: investigations May just confirm the clinical impression gained from history and examination, but may help quantify the problem and assist in pred iction of outcome. • CXR: may show emphysematous bullae, hyperinflation, patchy atelectasis, fibrosis. • fCG: may show right heart strain, low voltage. • FBC: polycythaemia, leucocytosis. • Arterial blood gases on air: evaluation of baseline preoperative status and confirmation of CO2 retention if suspected. • Pulmonary function tests: spirometry typically shows decreased FEV, and decreased FEV, : FVC (forced vital capacity) ratio.A large number 01variables can be defined. Flow- volume loops may be of more use in characterising airway obstruction. An FEV1 : FVC ratio of <50% is associated with increased morbidity and mortality after all forms of body cavity surgery. • Predictors: FEV1 < 1 L. p.C02 > 7 kl'a, FEV! : rvc ratio <50'>:••111 predict n-quin-rm-nt for postoperative ventilatory support (p.trlkul.trly .,fh·r u!'pt.·r . .. 1 ..._1 ... ...1 ... .. ,I.....",·i•. loil l r U I ' r v ).
  4. 4. Perioperative risks: anaest hesia and surgery Anaesthesia • Pulmonary function. Exerts a generally deleterious effect. Decrease in FRC (33%), VC (up to 50%), pulmonary compliance etc. follow all forms of general anaesthesia. Atelectasis, hypoxaemia, hypoventilation are common. • Barotrauma Associated with IFPV and airways resistance. Use of N2 0 in presence of bullae or emphysematous blebs. • Airways reactivity Associated with intubation, airway manipulation. May be provoked by histamine releasing anaesthetic agents (avoid). Surgery • Body cavity surgery is associated with significant morbidity: Thoracic and upper abdominal > lower abdominal. Prolonged surgery in supine position. Diaphragmatic excursion is impaired, restricted respiratory expansion d ue to pain. Risk reduction The key to risk reduction is the optimisation of the patient's perioperativc condition: • Smoking. Cessation is difficult in patients w ith a lifelong habit, but reduction in postoperative respiratory morbidity will result it it can be achieved 2 months prior to surgery. • Pharmacology. Optimise the regimen, particularly if there is a reversible component. Appropriate antibiotic treatment of any intercurrent chest infection. • Physiotherapy. Pre-emptive and with use of techniqu es such as incentive spirometry. • Analgesia. Good postoperative analgesia (i.e. by epidural) will reduce respiratory complications incident upon diaphragmatic splinting and basal atalectasis due to inhibition of deep breathing by pain. • Regional anaesthesia. Use wherever feasible, but must beware anaesthetising the intercostal muscles with high neuraxial blocks, or using techniques which impair phrenic nerve function (interscalene block). • Ambulation. Encourage early mobilisation. Marking points: Clinical experience and judgement is as important as the respiratory numbers in deciding whether or not these patients are going to require postoperative intensive care. You need to emphasise those clinical features as well as outlining an anaesthetic strategy that will minimise that risk. Good preoperative preparation and optimal postoperative analgesia are crucial to that aim.