Examining the Data: High Volume Surgical Procedures that Lead to Surgical Site Infection Requiring Patient Oversight After Discharge

  A 43-year old women, referred by an OB/GYN, presented to the wound clinic 35 days post abdominal hysterectomy for evaluation of an abdominal incision recalcitrant to healing. In addition, the patient recently returned to work and she reports having controlled diabetes for 5 years, is positive for family history of heart disease and has a BMI of 28. Post discharge, she had two episodes of a high fever and two visits to her Ob/Gyn for examination. Once visit for a, dressing change to drain the incision site, and another when she experienced vaginal discharge early on; which she reports has recently resolved. She received one course of antibiotics and continues to take pain medication. Today her temperature is 39C, there is a small purulent drainage from her deep abdominal incision, and the skin around the incision is red, warm and tender to the touch. Her main complaint is abdominal pain and the presence of a ‘hard lump’ beneath the abdominal incision. Upon examination, a 1.5-centimeter region of dehiscence is noted approximately 2 centimeters medial and proximal to the incision. A Complete Blood Count (CBC), complete chemistry panel and abdominal MRI are ordered to determine if there is a deep incision infection. The hospital admitting office is contacted in case an inpatient admission is needed.

  This patient has presented with a post surgical site infection (SSI) post abdominal hysterectomy, one of highest volume surgical procedures in the U.S. More than 650,000 hysterectomies are performed each year in the US, with more than 60% from the abdominal approach.¹ With an estimated infection rate of 10-15%, roughly 40,000 to 55,000 women annually may require medical intervention for SSI that progressed to a chronic wound after they being discharged from the hospital.² In 2006, there were approximately 1.6 million cesarean sections performed in the US with 21,124 patients admitted for post partum surgical complications.¹ Given the incidence of SSI of abdominal incisions, this represents a population of 160,000-190,000 women that may require further medical oversight provided in an outpatient wound clinic. An outpatient wound clinic presents a setting where these patients can receive focused follow up care for their SSI and perhaps receive most treatments as outpatients.

  Reaching out to this patient population represents a growth opportunity. The medical staff of the wound clinic working in tandem with the inpatient medical staff could develop surveillance criteria to identify patients at risk for SSI. Upon patient discharge, the wound clinic would be notified of patients found to be at risk for SSI. Personnel from the wound clinic could implement a post discharge patient follow-up program and call the patient to verify recovery is progressing normally. While discussing with the patient, health information could be provided to reiterate signs of SSI requiring medical attention. The post discharge program may include outreach efforts to the community OB/GYNs. Providing this referral source with educational material highlighting the normal progression of a surgical incision and when the patient is best served by a referral to a specialist trained in advanced wound care techniques will result in the most cost effective course of treatment for the patient and reduce risk of SSI.

Prevalence and Severity of SSIs

  Based on extensive epidemiological surveys, it has been estimated that SSI develops in at least 2% of hospitalized patients undergoing operative procedures, although this is likely an underestimate due to incomplete post-discharge data.³ SSIs are an important post operative complication, occurring in 2-5% of patients after clean extra-abdominal surgeries (eg, thoracic and orthopedic surgery) and in up to 20% of patients undergoing intra-abdominal procedures.^4-7 These complications increase morbidity for patients and consume substantial additional resources.⁸

Definition of SSI

  Surgical site infections include superficial incision infections, infections of the deep incision space, or organ space infections. The Centers for Disease Control and Prevention (CDC) consider SSI to be an infection that occurs somewhere in the operative field following a surgical intervention. This includes both incisional SSI and organ space SSI. Incisional SSI is subdivided into superficial and deep SSI. Superficial SSI occurs when the infection is limited to the skin and subcutaneous tissue only. Deep SSI extends into the deeper tissues, such as the fascial and muscular layers of the body wall. Organ/space SSI is an infection that occurs anywhere within the operative field other than where the body wall tissues were incised. Examples include intra-abdominal abscess developing after an abdominal operation, empyema developing after a thoracic operation, and osteomyelitis or joint infection developing after an orthopedic procedure.⁸ The National Healthcare Safety Network (NHSN) of the CDC has developed a series of criteria in an effort to objectively define SSI.⁸ Although these criteria are relatively detailed, it is important to realize that the surgeon’s judgment ultimately determines whether an SSI is present in equivocal cases.

  The CDC’s National Nosocomial Infections Surveillance (NNIS) system, which monitors reported trends in nosocomial infections in participating US acute care hospitals, found:
    1) 38% of all nosocomial infections in surgical patients are SSIs
    2) 4 to 16% of all nosocomial infections among all hospitalized patients are SSIs
    3) 2 to 5% of operated patients will develop SSI
    4) SSI increases length of stay in hospital by an average of 7.5 days
    5) $2,734 to $26,019 extra cost per SSI (1985, US dollars)
    6) $130 million to $845 million per year estimated national costs in the U.S.⁸

Implementing a Post Discharge Surveillance (PDS) Program

  A wound clinic serves an ambulatory population that includes patients recently discharged from the hospital. By instituting a surveillance practice to detect patients requiring medical attention for SSI after discharge, and fostering an outreach program as an extension of the discharge process, the clinic would be providing a needed medical service to the community and to the hospital’s medical staff. Studies using PDS methods have reported higher rates of postoperative infection than when the incidence is measured prior to discharge.⁹ Specifically, abdominal surgical site infections are among the most common complications of elective and emergent surgery and have serious consequences for outcomes and costs. Different risk factors may be involved, including age, sex, nutrition and immunity, prophylactic antibiotics, operation type and duration, type of shaving, and secondary infections.

  The incidence of SSI diagnosed prior to discharge is difficult to track and underestimates the true incidence that will be seen in a wound clinic or by the patient’s internal medicine physician or Ob/Gyn. In the Netherlands a study was undertaken to determine the most effective PDS to monitor SSIs after discharge. The Dutch National Nosocomial Network collected data on 131,798 surgical procedures performed in 64 of the 98 Dutch hospitals. The PDS most effective included a registration card in the patient’s chart to be completed upon their routine follow up visit to the outpatient clinic. The PDS reported an incidence of 79% SSI of appendectomy operations, 64% of knee prosthesis surgeries, 61% of mastectomy, 53% of femoropopliteal or femorotibial bypass surgery, and 53% of abdominal hysterectomy procedures.⁹

  It has been hypothesized that laparoscopic surgery as opposed to open surgery may result in fewer SSIs. A team of researchers from the University of California, San Francisco, monitored 1,662 admissions from 22 hospitals using a The Nosocomial Infection Marker (NIM™, patent pending). They were able to provide estimates of nosocomial infection risks associated with laparoscopic as compared to open surgery in three procedures: cholecystectomy, appendectomy, and hysterectomy. As compared to open surgery, laparoscopic cholecystectomy and hysterectomy were associated with statistically significantly lower risks for nosocomial infections.¹⁰

  Nevertheless, moving toward laparoscopic techniques will not eliminate the incidence of SSI. Less invasive laparoscopic myomectomy and myomectomy performed robotically using the daVinci robotic surgical system, reported SSI requiring further wound care treatments of 6.5%. Using 6.5% as an estimate of SSI resulting in a non healing superficial or deep tissue post surgery complication, equates to roughly 42,250 women across the U.S. that may present at a clinic requiring evaluation and treatment.^11,12

Incidence of Patients at Risk for SSI Identified Post Discharge

  Table 1. This represents the number of patients admitted to US hospitals with a diagnosis directly related to wound care of a surgical complication. An analysis of all discharges from US hospitals in 2006 identified 1,944,413 (5%) patients admitted for medical care following a complication of an implant, or an infection from a surgical intervention requiring further treatment. If clinicians were referred for focused wound care treatment to an outpatient wound clinic, with medical specialists using advanced techniques. This patient population may be managed more cost effectively and perhaps reduce the higher cost of inpatient admissions.

If Physicians Referred Patients to an Outpatient Wound Clinic

  Due to the frequency and clinical significance of SSI, rates are of interest to regulatory agencies and to the public at large. Public reporting of SSI rates by healthcare entities is increasingly required, and this mandate is being extended to individual surgeons. Further, a number of regulatory programs have been implemented that apply both financial incentives for following best practices in preventing SSI as well as financial penalties when such infections occur. Starting in 2009, Centers for Medicare and Medicaid Services (CMS) will stop reimbursing hospitals for certain complications, including surgical-site infections, catheter-associated urinary tract infections, and central-line associated bloodstream infections.¹³ Given the incidence of SSI, it is imperative that the wound clinic medical personnel work in tandem with the inpatient surgical services to be:
    A) Implement risk criteria stratification to identify patients at a high risk for SSI after discharge.
    B) Train the outpatient wound clinic staff to recognize patients presenting with SSI.
    C) Have a protocol in place for the management of SSI, focused on cost effective outpatient treatments, followed by inpatient admission policies and procedures to streamline the patient’s inpatient services and therefore minimize the costs and enhance the probability of a positive outcome.

  Support materials to initiate this program may be found at the CDC. The CDC has a risk factor classification scheme to identify types of surgery more likely to result in SSI. Further to better recognize those patients at a higher risk for SSI, it is important to identify patient specific risk factors such as age, presence of remote infection, diabetes, peripheral vascular disease, delayed administration of antibiotics, nutritional status, and discharge status.^14-17

  Leah Amir, MS, MHA has published on the importance of outcome measures and the need to improve the practice of wound care worldwide by applying scientific rigor to clinical trials to measure the effects of wound care mtreatments. Email her at LeahAmir@VantageView.com.

  The author would like to thank Dr. John P. Kirby for his assistance in developing this article.

References

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2. A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)

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10. Brill A, Ghosh K, Gunnarsson C, et al. The effects of laparoscopic cholecystectomy, hysterectomy, and appendectomy on nosocomial infection risks. Surg Endosc. 2008;22(4):1112–1118.

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12. Advincula AP, Song A, Burke W, Reynolds RK. Preliminary experience with robot-assisted laparoscopic myomectomy. J Am Assoc Gynecol Laparosc. 2004;11(4):511-8.

13. Federal Register / Vol. 73, No. 161 / Tuesday, August 19, 2008 / Rules and Regulations: 48471-48472.

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15. Garner JS. CDC guideline for prevention of surgical wound infections, 1985. Supersedes guideline for prevention of surgical wound infections published in 1982. (Originally published in November 1985). Infect Control. 1986;7(3):193-200.

16. Mangram AJ, Horan TC, Pearson ML, Silver LC, Jarvic WR. Guideline for prevention of surgical site infection, 1999. Hospital Infection control Practices Advisory Committee. Infect Control Hosp Epidemiol. 1999;20(4):250-278.