It's not just about creating a program for active patient warming. It's also about altering long-held perioperative mindsets.

When Anita Volpe, DNP, APRN, began working at New York-Presbyterian Queens Hospital in Flushing, N.Y., prewarming patients was simply not done. That alarmed her, because she had been tasked with reducing the facility's rate of surgical site infections (SSIs) among colorectal surgery patients, which was a negative outlier compared with other facilities in the state. When she asked OR leaders why they weren't prewarming patients, they essentially told her that patients were warm enough.
That initial response hit Dr. Volpe hard. As the director of surgical outcomes, research and education for the hospital's department of surgery, she was tasked both with properly introducing new warming methods and fighting a cultural battle.
Dr. Volpe offers compelling statistics in support of patient warming: Research shows 70% of surgical patients develop inadvertent perioperative hypothermia (IPH); patients who lose just one degree of body heat are at increased risk of a morbid event; and IPH is associated with an increased incidence of post-op infection. "When it comes to maintaining normothermia, there's simply no excuse for not actively prewarming your patients," she says.
Dr. Volpe collaborated with nursing, surgical and anesthesia leaders to develop a colon bundle for the facility, and active patient warming was a major new component. To ensure staff followed standardized warming protocols, she explicitly laid out the many risk factors of IPH in the policy, and instructed staff to pay extra attention to patients who exhibit them during pre-op screening. Pediatric and geriatric patients are most at risk, she says, with other susceptible patient populations including individuals with BMIs of 17 or below, and those on psychotropics, antidepressants or thyroid supplements. Procedure type and anesthesia technique also play a role.
The policy calls for continued active warming when patients enter the OR. Depending on the situation, staff may also need to increase ambient room temperature or use warmed irrigation solutions. The policy requires continued assessment and monitoring in the PACU to make sure patients' body temperatures remain at or above 36°C for their entire stay.
Dr. Volpe also enforced a single temperature monitoring method, which meant standardizing on either oral or axillary temperature readings. Sometimes both were being performed on the same patient. "These methods simply aren't equitable, and an inconsistent method of temperature-taking could impact the effectiveness of your warming practices," she says. "Pick one and stick with it."
In Dr. Volpe's view, active warming is the only effective method of maintaining normothermia. Her facility's guideline, for example, requires active prewarming for a minimum of 30 minutes for patients scheduled to undergo procedures lasting 30 minutes or more.
"Despite active warming's clear benefits, plenty of surgical facilities still give patients a warmed blanket in pre-op and consider that acceptable," she says. "Cotton blankets might make patients feel warm and comfortable, but research shows the heat they give off lasts for only about 10 minutes and does not impact core body temperature."
Dr. Volpe also notes this passive warming method increases linen costs and inventory, and that staff must dedicate time to loading blanket warming units and reapplying blankets in pre-op. "That's a lot of inefficiency for no gain in clinical outcomes," she says.
Ultimately, says Dr. Volpe, active warming can reduce SSI costs and improve outcomes. "To gain buy-in, consider that you'll be saving money on postoperative morbidity," she says. "Warm patients wake up quicker because they metabolize anesthetics at an increased rate. They're able to fight off infection because their tissue oxygenation levels are higher. They heal better and they're more comfortable."
Today, Dr. Volpe proudly notes her hospital is a positive outlier, with SSI rates well below the state's average. Patient warming was a big part of that reversal. "Your ultimate responsibility is to ensure patients achieve the best possible outcomes," she says. "If you don't have a standardized patient warming protocol in place that includes active prewarming, that responsibility isn't being met."