1. Surgical Site Infections: The Foundation

2. What Are We Doing Together Over the Next Two Months Talk about ways to prevent surgical site infections and venous thromboembolism in surgical patients. Webinars every two-weeks where we will discuss methods that appear in the literature and that are “low-hanging fruit”. The topics that we discuss are things that: –will make the most difference to your patients –have clear evidence –are things that you can put into place in your ORs

3. We Will Not Go Into Step-By Step Instructions On How To Put These Methods Into Place

4. Today’s Topics Brief History of Infection Prevention Techniques Prophylactic Antibiotic Administration Weight Based Dosing Re-dosing Discontinuing Antibiotics

5. Common Sense Science Bacteria cause infection Bacteria are everywhere It is a battle against the bacteria

6. Ignaz Semmelweiss Joseph Lister Louis Pasteur Brief History of Infection Prevention

7. Surgery – 1969 Postoperative Wound Infection: A Prospective Study of Determinant Factors and Prevention Polk HC Jr, Lopez-Mayor JF

8. Surgical Technique, Prophylactic Antibiotics and SSI Polk. Surgery 1969;66:97-103

9. Different Ways of Preventing SSI’s Pre-operative screenings Proper Hair Removal Skin Prep Hair Prep Hand Hygiene Prophylactic Antibiotics Surgical Technique Glucose Control Hyperoxia OR Traffic Bowel Prep Temperature Control Transfusion Maintenance of hemostasis and perfusion Wound Protectors Communication Teamwork

10. Preventing SSI’s Pre-IncisionIncision/SurgeryPost Op Patient Basics of Skin Prep Showers Skin Wipes Hair Removal Weight Based Dosing MRSA Screening Glucose Control Hyperoxia Wound care Dressings Operation Antibiotic Bowel Prep Re-dosing Operating Time Use of Tourniquet Surgical Technique Wound protectors Environment Basics of Sterility Instrument Sterility Hand Hygiene Temperature Control Teamwork Culture Basics of Sterility Instrument Sterility Hand Hygiene OR Traffic Temperature Control Teamwork Culture Discontinue antibiotics Teamwork Culture

11. Rates of Surgical Site Infection and Benefit From Prophylactic Antibiotics Operation Antibiotic Yes Antibiotic No Number Needed to Treat Colon4-12%24-48% 3-5 Other (mixed) GI4-6%15-29% 4-9 Vascular1- 4%7-17% 10-17 Cardiac3-9%44-49%2-3 Hysterectomy1-16%18-38%3-6 Craniotomy0.5-3%4-12%9-29 Spinal Operation2.2%5.9%27 Total Joint Replacement 0.5-1%2-9% 12-100 Breast & Hernia Operation 3.5%5.2%58 Dellinger, Patchen 2013. Hospital Engagement Network

12. Common Sense Science: Timing of Antibiotics In order for antibiotics to be effective they need to be in the tissue at the time that the incision is made. It can take more time to reach some tissues than others. Antibiotics can’t get to tissue that has no blood flow.

13. Classen. NEJM. 1992;328:281. Perioperative Prophylactic Antibiotics Timing of Administration Infections (%) Hours From Incision 14/369 5/699 5/1009 2/180 1/81 1/41 1/47 15/441

14. Common Sense Science: Weight Based Dosing Larger patients have more tissue and larger blood volumes. Standard antibiotics doses given to larger patients will result in lower blood and tissue levels of antibiotics. The dose of prophylactic antibiotic should be adjusted for larger patients.

15. Obesity Map

16. Prophylactic Antibiotics: Size of Patient and Size of Dose Morbidly obese patients having bariatric surgery have higher infection rates. Cefazolin levels are lower in obese patients than in non-obese patients at same dose. Cefazolin dose changed from 1 g to 2 g: –Infection rate at 1g: 16.5% –Infection rate at 2g: 5.6% Forse RA. Surgery 1989;106:750

17. Ancef Pediatric Dosing: – 25 – 50 mg/kg/day divided into three doses 70kg x 50 = 3500 3500/3 = ~1000 or 1 gram 100kg x 50 = 5000 5000/3 = ~ 1700 or 2 grams

18. Recommended Adult Dosing < 80 kg -------- 1 gram > 80 kg -------- 2 grams

19. Common Sense Science: Antibiotic Re-dosing The blood level of all antibiotics decreases with time. When the level falls enough, the infections “fighting power” of the antibiotic is no longer effective. A second [or third] dose of antibiotics should be given to prevent surgical site infection.

20. Results When You Re-Dose Antibiotics

21. How Long Between Re-Dosing? It turns out that if antibiotics are re-dosed they can remain clinically effective. There is probably some variability in this [different surgical procedures can change drug metabolism]. Other factors can decrease this interval.

22. Common Sense Science: Discontinuing Prophylactic Antibiotics The primary effect of giving antibiotics during surgery comes from the initial dose given before the incision and additional doses given while the incision is open. That is when most of the bacteria contamination occurs. Additional doses of antibiotics given after the wound is closed have minimal or no effect on the development of surgical site infections.

23. Antibiotic Resistance is a Big Problem NEJM: Pallares et al. Vol. 333:474-480.

24. Staphylococcus Aureus Emerging Infectious Diseases: Vol.7 No. 2. Chambers, H.F.

25. Vancomycin

26. Take Home Messages This is hard. The GREATER GOOD. My patient.

27. ? ? Questions

28. Upcoming Calls Thursday, May 16 th 2:00-2:45: The Impact of Communication, Teamwork, and Culture on SSI’s. Thursday, May 30 th 2:00-2:45: Preventing SSI’s When Preparing Our Patients for Surgery

29. Office Hours: Wednesday 2:00-3:00

30. Resources Website: www.safesurgery2015.org Email: safesurgery2015@hsph.harvard.edu