The Use of Diluted Povidone Iodine Irrigation in Spine Surgery

We had very low recruitment rates that would have resulted in several years being added to the study to achieve an appropriate sample size.

The purpose of the study is to determine whether diluted Povidone Iodine solution used to irrigate surgical wounds during spine surgery decreases the incidence of surgical site infections.

Post-operative infections in spine surgery have been extensively investigated in the literature. These investigations focus on the efficacy of using peri-operative antibiotics, Povidone Iodine skin preparations, the effects of shaving around the surgical sit, and the use of intra-operative diluted Povidone Iodine wound irrigation in preventing post-operative infections. Povidone-iodine is a complex of polyvinyl pyrrolidine and tri-iodine ions widely used as an antiseptic agent. It has bactericidal activity against a wide spectrum of pathogens, including methicillin-resistant Staphylococcus aureus (MRSA). The safety of its use intra-operatively has been evaluated in animal studies and also supported through Randomized Controlled Trials in spinal surgery and in other surgical subspecialties. The purpose of this study is to evaluate the efficacy of the intra-operative use of diluted Povidone Iodine solution in reducing post-operative infections when used for irrigating surgical incisions during spinal surgery compared with 0.9% Sodium Chloride Irrigation Solution (i.e. normal saline solution). The primary outcome measure will be seen as a reduction in the number of post-operative infections. As a result and although not directly measured, it is suspected that a reduction in post-operative infections may result in quicker healing with fewer complications and pain.

Subjects in the treatment group will receive 3.5% diluted Povidone Iodine solution in the surgical incision in a quantity sufficient to fill the wound to the level of the skin. The Povidone Iodine solution will be maintained in the incision for 3 minutes, after which it will be flushed from the wound with normal saline solution.

Subjects in the Placebo Comparator group will receive normal saline solution in a quantity sufficient to fill the wound to the level of the skin. The saline solution will be maintained in the incision for 3 minutes, after which it will be flushed from the wound with additional saline solution to replicate the saline wash procedure followed in the Treatment group.

The Centers for Disease Control (CDC)definition of surgical site infections (SSI)will be used for this study.This definition addresses both superficial and deep surgical site infections. Outcome will be determined by the number of superficial, deep, and total (superficial plus deep) wound infections for each group.

Inclusion Criteria: Age of 18-75 Undergoing posterior surgical spinal procedure for degenerative spine disease, extra-dural tumors, trauma, or spinal deformity No obvious potential infective focus Patient willing to enroll Exclusion Criteria: Age <18 or >75 Identified infective focus in the body, including furuncles,or acne at surgical incision site Patient with discitis or spinal osteomyelitis Dural tear Potential use of Bone Morphogenic Protein (BMP) Iodine hypersensitivity Out of province patients due to difficulty in arranging follow up visits Minimal invasive spine surgical procedure (MISS) due to difficulty of having diluted Betadine solution contact soft tissue with the use if MISS retractors Pregnancy Inability to provide informed consent

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