Post Opertion Infection

Post Opertion Infection

Introduction

Infection can be a disabling complication of any surgical procedure. Due to the close proximity of the neurological structures, spinal infection can be particularly devastating. It can lead, not only to chronic pain and deformity, but worse to paralysis, and potentially, death. Many factors impact the postoperative occurrence of infection. These factors can be divided into those attributable to the patient, surgical environment, and type of procedure performed. Many factors affect the risk of developing an infection, not the least of which is the health of the patient. Patient weight, glucose regulation, nutritional health, smoking status, and specific disease are all factors that play roles in this complex interplay.

Obese patients present many problems for the surgeon, including an increased risk of postoperative infection.1 Cruse and Foord1 in their study on surgical site infections found a 14% infection rate in their patients defined as obese due to increased exposure necessary to complete the operation and the reduced vascularity of adipose tissue relative to muscle. Obese patients, despite their caloric abundance, may be malnourished as well.2Another factor is fat necrosis, which can occur with the use of self-retaining retractors and electrocautery. Diabetes also leads to an increased risk of postoperative infection. Simpson et al,3compared diabetic to nondiabetic patients undergoing a posterior decompressive procedure and found 95% of the nondiabetics and only 39% of the diabetics obtained excellent or good results. They also found a 24% incidence of superficial wound infection, and 10% incidence of deep infection in the diabetic patients contrasted to no infections in the nondiabetic population.

Diabetes not only increases the rate of infection, but affects the ability to heal the operative incision as well. Polymorphonuclear neutrophil leukocytes, lymphocytes, and macrophage function are abnormal in patients with diabetes.4-6 Diabetes decreases leukocyte adherence, chemotaxis, phagocytosis, and diapedesis. However, physicians can maintain phagocytic activity and bacterial killing by lowering blood glucose levels to normal.7 The long-term consequences of diabetes are micro and macrovascular in nature with a higher incidence of peripheral vascular disease that can lead to decreased wound healing as well.8 The high blood sugar of diabetic patients suppresses their ability to eliminate and remove bacteria. Their relative poor blood supply secondary to their vascular disease also lengthens healing intervals by decreasing the supply of critical factors for cellular function such as oxygen. Poor blood supply also decreases the penetration of antibiotics to their target areas (Cruse, 1973).

Another factor that increases the risk of postoperative infection is malnourishment.2 Klein et al9 found that preoperative nutritional status was a strong predictor of postoperative complications. One hundred fourteen patients undergoing lumbar decompression and fusion were analyzed with respect to serum albumin and total lymphocyte count. Values <3.5 g/dL for serum albumin and <1500 for total lymphocyte count were considered thresholds for malnourishment. Of the 13 postoperative infections, 11 were found to be malnourished. The article also reported on 27 patients treated for vertebral osteomyelitis and found that 24 of the 26 postoperative complications occurred in the malnourished ...