Delaying surgery

1. Delaying surgery • Pre-operative assessment and investigations

2. Overview • This talk will look at: • Medical conditions whose investigation and optimisation may require a delay of surgery, and the indications for this. • Other factors that may have the same effect (location, timing of surgery, availability of beds). • Options for information gathering and ongoing quality control.

3. Objectives • “Peace in our time”

4. Objectives • Consistency where possible in the perioperative management of medical conditions that have the potential to delay surgery. • An understanding of the risks associated with these conditions in the perioperative period. • Consultation with surgical services on these issues.

5. Importance of adequate preoperative workup • Many conditions, if left uncorrected, pose a serious risk of perioperative morbidity or mortality. • At times this may require a delay or cancellation of surgery for optimisation.

6. AIMS Review • Kluger et al. Inadequate pre-operative evaluation and preparation: a review of 197 reports from the Australian Incident Monitoring Study. Anaesthesia 2000; 55: 1173-1178. • 726 of the first 6271 incidents reported to AIMS • 197 had clear issues with assessment • 10% had not been seen • “Unpreventable” incidents made up only 5% of cases

7. Guiding principles • Patient safety is the primary concern • Often no clear guidelines so need to consider risk vs benefit • Optimisation vs urgency of surgery • Will the investigation or review change management?

8. Medical Conditions that may cause a delay of surgery

9. Overview • Cardiac • Respiratory • Electrolyte disturbances • Anticoagulation • Diabetes • Anaemia and perioperative blood transfusion

10. Cardiac conditions • Ischaemic heart disease: • AHA 2007 “Active Cardiac Conditions for which the patient should undergo evaluation and treatment before elective noncardiac surgery” (Table 2)

11. Cardiac conditions continued • Heart failure: Associated with a substantially increased risk and should be optimised before surgery (AHA 2007). • Perioperative arrhythmias: Should be controlled preoperatively as surgery and anaesthesia can cause marked deterioration • Preoperative pacing indicated for symptomatic 1st degree heart block ; 2nd and 3rd degree heart block; slow rates unresponsive to drugs

12. Valvular disease • AHA Guidelines (2007) • Severe AS poses the greatest risk. Then look at patient’s symptoms: • Asymptomatic: Requires evaluation of valve if none in past 1 year • Symptomatic: Requires valve replacement (delay surgery) • If valve not replaced perioperative mortality approximately 10% • Patients with valve disease severe enough to warrant surgical treatment should have valve surgery before elective noncardiac surgery

13. Pacemakers and implantable defibrillators • Should have been checked in the last 6 months. Make sure all important information is available and documented. • Know type and response to magnets • ECG

14. Pulmonary hypertension • Defined as mean pulmonary artery pressure >25mmHg • >35mmHg = severe • RVF if >50mmHg • Recent patient: 51 year-old male with MPAP >70mmHg • For vascath + bilateral inguinal hernia repairs • Options are: Do at DBH, delay and transfer, or cancel surgery.

15. Hypertension • No absolute contraindications to surgery. • AHA 2007: SBP>180mmHg and DBP>100mmHg are not independent predictors of increased risk of perioperative complications. • Need to consider risk vs. benefit of delaying surgery in these cases • No evidence that it is beneficial to delay surgery if hypertension mild or moderate and no associated metabolic or cardiovascular abnormalities. • RPAH: Ideally want <140/90; consider referral for optimisation if >160/100

16. RPAH Guidelines • “All patients should have their cardiac disease optimised prior to surgery.” • If cardiac history/condition is unclear or are concerned => cardiology referral. • Echo for • Significant uninvestigated murmur • Marked SOBOE (without another explanation) • Incompletely compensated cardiac failure • Stents: No elective surgery for 6-12 weeks after insertion unless continuing on antiplatelet therapy • History of CVA: Asymptomatic with >70% stenosis require intervention. History of stroke => find and correct cause.

17. Respiratory conditions • AHA 2007 • Patients with obstructive or restrictive disease are at increased risk of perioperative complications. • May be justified in investigating if significant pulmonary disease is suspected: functional capacity, response to bronchodilators, CO2 retention (ABG analysis). • Infection = treat with antibiotics.

18. Respiratory Conditions • Oxford Handbook • If surgery does not involve the abdominal or chest cavities, even patients with severe respiratory disease are at low risk for serious postoperative pulmonary complications • Spirometry does not predict pulmonary complications even in patients with COPD. “No spirometric values should be viewed as prohibitive for surgery.” • Respiratory tract infections: Patients with RTIs causing fever and cough (with or without chest signs on lung auscultation) should not undergo elective surgery under GA due to increased risk of postoperative pulmonary complications. • Simple coryza does not equal increased risk of postoperative complications unless pre-existing respiratory disease or are undergoing major abdominal or thoracic surgery • Children with recent or acute RTIs are more likely to suffer transient postoperative hypoxaemia (especially if intubated)

19. Electrolyte disturbances • Consider causes • Consider implications of deranged levels • Rate of change is often more significant than absolute level in determining urgency of correction

20. Sodium • Hyponatraemia: Postpone elective surgery if Na<120mmol/L or symptomatic • Rapid correction carries risk of central pontine demyelinosis • Optimum rate of correction unknown but around 0.5-2 mmol/hr suggested • Hypernatraemia: Postpone elective surgery if Na>150mmol/L

21. Potassium • Hypokalaemia • Arrhythmias, myocardial dysfunction, muscle weakness (case reports of respiratory failure) rhabdomyolysis, renal i.e. can cause dysfunction in many organ systems. • Chronic mild hypo (3-3.5) without ECG changes does not appear to substantially increase anaesthetic risk • Hyperkalaemia: Always treat if >6-6.5 or ECG changes • Oxford Handbook: “Do not consider elective surgery.”

22. Diabetes • AHA 2007 • Raised intraoperative BSL is an important predictor of morbidity and mortality. • Stroke, MI, death increased by 3-4x if pre-op BSL >11.1mmol/L (study was in patients undergoing carotid endarterectomy, i.e. known disease) • Exact target unclear but say <8.3mmol/L is satisfactory. • American College of Endocrinology 2003 • BSL not greater than 10

23. Anticoagulation • The Perioperative Management of Antithrombotic Therapy. American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest 2008; 133:299 –339S. • Recommend INR be managed to <1.5 before surgery • For urgent surgery: If surgery can be delayed by 18-24h, 2.5-5mg of vitamin K can be effective. If more urgent (<12h), recommend FFP (or other prothrombin concentrate) in addition to vitamin K.

24. Anaemia and perioperative blood transfusion • Lack of clear guidelines but transfusion thresholds probably lower than those used. • AHA 2007: “A conservative approach to transfusion is warranted.” • Consider cause of anaemia

25. Other sources • Oxford Handbook: “There is no absolute level of haemoglobin at which transfusion of red cells is appropriate for all patients.” • Classifies by loss of circulating blood volume (15-30%: Unlikely unless indicated by comorbidities; >30%: transfusion probably required) • Suggests Hb<100 is not an indication but Hb<70 almost always is. • British Journal of Haematology 2001: Guidelines for the clinical use of red cell transfusions • Source used for Oxford Handbook guidelines • No definite Hb level; no transfusion back to “normal” pre-operative Hb • No clear guidelines for Hb between 70 and 100

26. Other factors that may lead to delay of surgery

27. Location of surgery • Patients with stents (especially DES): Given the high risk of reinfarction if antiplatelet drugs are stopped, should the surgery be performed in a centre where a new stent can be inserted if they infarct? • Other indications for tertiary referral: CPB, neurological, some paediatric surgery, PAH.

28. Bed availability • Availability of ICU/HDU beds: Patient may need transfer for this reason alone. • Paediatric ICU: None at DBH so will need transfer.

29. Social and geographical issues • Does the patient have somewhere appropriate to go after discharge? • Availability of doctors in remote areas for follow-up of these patients.

30. AwAITING INFORMATION • Awaiting old notes • Awaiting relevant blood results • This issue exacerbated by lack of electronic records. Electronic record keeping can contain: • Previous discharge summaries • Clinic letters and investigations (e.g. echo reports) • Anaesthetic clinic letters

31. Information gathering and quality control

32. Communication with surgical teams • Cosgrove et al. Decreasing delays in urgent and expedited surgery in a university teaching hospital through audit and communication between peri-operative and surgical directorates. Anaesthesia 2008;63(6):599-603. • Prospective audit over a 5 month period. Looked at reasons for delay in surgery. • Results communicated to all concerned and then re-audited. No other intervention.

33. Fin