Anesthesiologists must be key participants in the process of reducing surgical site infections, including ensuring that the correct prophylactic antimicrobial therapy is given 30 to 60 minutes before incision.
This is just one of many updated SSI guidelines that were recently published in the Journal of the American College of Surgeons (2017;224:59-74).
“Anesthesiologists need to embrace their role as part of the surgical team, particularly in teaching institutions, instead of relying on the junior-most person to make decisions affecting surgical site infections,” said co-author Therese Duane, MD, MBA, vice chair for quality and safety, and medical director of acute care surgery research, in the Department of Surgery at John Peter Smith (JPS) Health Network, in Fort Worth, Texas.
When anesthesiologists ensure timeliness of appropriate dosing of antibiotics preoperatively, “patient outcomes are improved,” Dr. Duane said. “But when they do not engage actively in the process, results can be negatively impacted.”
Depending on the institution, this critical step can be quite challenging, Dr. Duane noted. “Often, anesthesiologists will wait to ask the surgeon what antibiotic he prefers. However, by that point, it is usually too late because the case has already started. Thus, if you do not have a plan in advance, it interferes with the timing of the antimicrobial.”
To ensure compliance with antimicrobials, Dr. Duane works in conjunction with antimicrobial stewardship partners, which includes an infectious disease–trained physician who directs the program and an infectious disease pharmacist. They review the hospital’s antibiograms to determine which antimicrobials are effective against the pathogens found to be present.
“We essentially set up a system whereby patients who do not necessarily have antibiotics ordered preoperatively are automatically given an antibiotic as they are being wheeled out of preoperative holding and into the operating room,” Dr. Duane said.
It is also important that patients are redosed at appropriate times, based on the drug’s half-life and the amount of blood loss.
At JPS Health Network, anesthesiologists have timers that alert them when it is time to redose.
Avoiding intraoperative hypothermia is another key component of minimizing SSI risk that anesthesiologists can control. “You have a patient who is completely unrobed in an environment with a lot of loss of body temperature,” Dr. Duane said. “Hence, it is important to cover the patient as quickly as possible. Using warming blankets over the patient and applying warming blankets and/or devices under the patient helps maintain normothermia.” Keeping the OR warm is also paramount.
Dr. Duane recommends that anesthesiologists be proactive in assuming that patients will be cold and have the patient covered as much as possible, from head to toe, with the exception of the operative field. “Ideally, one should try to prevent the patient from becoming cool in the first place,” she said. “But this takes a fair amount of vigilance.”
Another way to reduce SSIs is by administering postoperative supplemental oxygen. “There is actually a value in providing more oxygen than previously thought,” Dr. Duane said. “By optimizing oxygenation, oxygen delivery is improved to the tissues. Presumably this maintains cellular function, making wounds more resistant to infection.”
However, the value of supplemental oxygen “has not been studied as much as some of the other measures to reduce infection, and certain studies show mixed results,” Dr. Duane noted.
The revised guidelines recommend administering oxygen at 80% for four hours in the PACU. “The problem, though, is that many patients do not stay in the PACU for a full four hours,” Dr. Duane said.
Moreover, patients transferred from the PACU to the floor encounter nurses “who assume they have to monitor oxygen saturation levels as well, which increases the patient’s level of care,” Dr. Duane noted. “So it is important to convey to the floor nurses that monitoring oxygen saturation is not needed, unless specified for a patient.”
Over the past several years, there has been a focus on achieving good long-term glycemic control preoperatively in patients with diabetes. “Although that is important, some studies demonstrate that perioperative glucose control is just as, if not more, important,” Dr. Duane said.
This finding is significant from an anesthesia standpoint because it is the anesthesiologists who “double-check blood sugars and treat intraoperatively,” Dr. Duane said. “This requires a change in workflow. Regardless of whether the patient is diabetic or not, it is important that blood sugar is checked on the morning of surgery. Also, if elevated, the patient needs to be treated. In essence, there has to be better glucose control throughout the duration of the case, and afterward, to minimize infection risk.”
However, there are often concerns raised by anesthesiologists that glycemic intervention will make the patient hypoglycemic by administering too much insulin, according to Dr. Duane, who is a general surgeon, trauma surgeon and surgical interventionist. “But you are not giving insulin to patients with a normal blood sugar, and you are not giving an excessive amount of insulin to other patients. The goal is to keep the patient in a tighter range of blood glucose levels.”
Another measure to reduce SSIs is foot traffic in and out of the OR. “Although little data exists on this topic, there has been shown an association between the OR traffic and the amount of pathogens found in the OR,” Dr. Duane said.
Anesthesiologists, in particular, can reduce the number of times they walk in and out of the OR. “The less traffic the better,” Dr. Duane said. “Every time you open that door, contaminants can come in.”
Dr. Duane said some institutions also have become more lax in clothing worn by staff, such as form-fitting jackets over scrubs to keep warm. “People should start thinking of clothing as a possible confounder and risk associated with SSIs,” she said.