1. Predicting & Preventing Postoperative Pulmonary Complication Wael A Batobara FRCPC Internal Med,Pulmonary & Critical care medicine ABIM Internal Med,Pulmonary & Critical care medicine

2. Case Scenarios A.65y male septoplasty Asthma B.45y female Lung resection COPD C.55y male Lap chole Pulmonary fibrosis D.50y male CABG heavy smoker

3. By the end of the talk Incidence & importance of postoperative pulmonary complication PPC Risk factors  Patient Vs procedure related Prediction tools & their efficiency Available guidelines Preventive measures

4. Incidence & Importance As common as postoperative cardiac complication Variable reported incidence  Definitions of PPC have varied widely + differences in the selection of patients Lawrence VA, J Gen Intern Med 1995

5. Incidence & Importance Recently only complications that either prolongs the hospital stay or to contribute to morbidity and mortality were reported. I - Pneumonia II- Underlying chronic lung disease exacerbation III- Respiratory failure with prolonged Mechanical Ventilation

6. Disease Severity Predicting Mortality in CABG Fuster et al Euro Jr Cardiothorac 2006

7. Patient related risk factors Age Studies suggesting an increased risk of PPC with older age have not generally controlled for coexisting conditions. When data were stratified according to the ASA  overall perioperative mortality for classes II through V is the same in all age groups. JAMA 1979; Anesthesiology 1973

8. Patient related risk factors Obesity Potential Difficult airway Restrictive disease which is accentuated postoperatively Obstructive sleep apnea & associated Pulmonary HTN Obesity hypoventilation Few review article didn’t find that obesity is associated with increased risk of PPC in abdominal Sx or lap chole Smetana, Chest 1999 Phillips,AJRCC 1994

9. Patient related risk factors Smoking Prospective study 489 ambulatory pt elective sx Smoker had a higher incidence of wound infections odds ratio 1.71 respiratory complications odds ratio 16.3 Myles Anesthesiology. 2002 Oct

10. Patient related risk factors Quitting smoking Randomized prospective trial 120 pts Counseling & nicotine replacement 6-8 weeks before Sx Smoker Quitter All complications 52% 18% Wound complications 31% 5% 2 nd Sx 15% 4% LOS 13 d 11 d Muller Lancet Jan 2002

11. Patient related risk factors The timing of quitting ?!!! 200 pts CABG post operative pulmonary complications Non smoker 11.9% Quit > 8 weeks 14.5% quit < 8 weeks 57% Active smoker 33% It takes few weeks for an improvement in ciliary and small airway function & a decrease in sputum production to happen. Abrupt absence of the irritant effect of cigarette inhibits coughing  secretions retention &small airway obstruction. Warner Mayo Clin Proc 1989

12. Patient related risk factors The timing of quitting ?!! 300 patients with Lung Ca going for thoracotomy 21% Non smokers 62% Past quitters ( more than 2 months) 13% recent quitters ( less than 2 months ) 4% ongoing smokers Barrera chest 2005

13. Quitting Timing in Thoracotomy Barrera chest 2005

14. Patient related risk factors COPD / Asthma Optimal control should be achieved before SX  bronchodilators, inhaled & systemic steroids potential adrenal insufficiency should be suspected RCT 40 pt with COPD FEV1 57% CABG & similar EF 55% Oral prednisolone 20 mg po od for 10 days Steroid Placebo FEV1 63% 57% Reintubation 0 4 ICU stay 2 5 Hospital stay 9 13 No difference in wound dehiscence or infection Hakan Jr Card Sx 2005

15. Obstructive Sleep Apnea American academy of Sleep Medicine 2008

17. Procedures related risk factors Anesthesia Effect on Respiratory physiology Central drive loss  blunted response to hypoxia & hypercapnia Reduction of respiratory muscle efficacy Reduced TV & RR  reduced Minute Ventilation  hypercapnia Atelectasis  V/Q mismatch & shunts  hypoxia

18. Procedures related risk factors Thoracic & Abd Sx effect on Respiratory physiology Reduced vital capacity 50% & FRC 30% Effect may last weeks Diaphragm function loss Diminished cough & mucocilliary clearance induced by anesthetic & analgesic  atelectaisis & pneumonia

19. Procedure Related risk factors Surgical site Thoracic sx 19-59%  Upper abd sx 17-76%  lower abd sx 0-5% Lap chole FVC reduction 23% Vs 50% with laparotomy Surgery Duration 3-4 hours PPC 40% Anesthesia Type Although inconsistent result postoperative regional anesthesia had less rate of PPC than general especially high risk pts

20. Epidural local Anas Vs Systemic Opioids Ballantyne et al Anasth Analg 1998

21. Epidural Opioids Vs Systemic Opioids Ballantyne et al Anasth Analg 1998

22. Sematana NEJM 2007