No one's ever mistaken a surgical gown for a down jacket, so patients will always appreciate the warm blanket you wrap around them or the active warming method you apply. What they might not realize is that your efforts to keep them comfortable are really aimed at keeping them safe. Warming patients before, during and after surgery limits the risk of post-op infections, improves wound healing and leads to faster recoveries.

Here's a rundown of several patient warming methods you can use to maintain normothermia based on insights from Paul Austin, PhD, CRNA, a professor of nurse anesthesia at Texas Wesleyan University in Fort Worth.

"? Cotton blankets. Patients love being wrapped in warmed blankets, but applying the common comfort measure alone won't prevent hypothermia. Blankets are best used to augment active heating measures and boost patient satisfaction scores.

"? Convective warming. Disposable and lightweight warming gowns help maintain the body's core temperature, but could impede access to the surgical site, meaning full body covers might have to be replaced with smaller coverlets in the OR. The debate about a popular forced-air warming unit's link to surgical site infections is currently playing out in the federal courts (see "Bair Hugger Absolved in Forced-Air Bellwether Trial" on below).

"? Conductive fiber warming. This solution directs heat through blankets and mattresses placed over and under the patient to warm from below and above at the same time. The fabrics on these devices must be covered with a disposable cover or disinfected between uses.

"? Warmed irrigation and IV fluids help maintain normothermia, particularly if the case includes administering large amounts of cold fluid quickly. An important note: Closely follow the directions provided by the manufacturers of fluid warming units that pertain to how long you can safely warm fluid and the maximum allowed temperature to which the fluid can be warmed. AORN suggests you warm IV and irrigation solutions in their own warming units or in units with separate blanket and fluid warming compartments that have independent temperature controls.

"? Thermal reflective blankets, which reflect the patient's radiant body heat to maintain body temperature, have some proven efficacy in preventing hypothermia, but are not as effective as active warming methods and cannot be used during all surgical procedures.

"? Warm circulating water mattresses can be effective in maintaining normothermia, but, depending on the patient's weight and the heat of the mattress, can increase the risk of pressure sores. These devices have largely fallen out of favor due to safety concerns and a lack of efficacy compared with other active warming methods.

"? Electric heating blankets effectively warm patients, but come with concerns of electrical hazards as a result of insufficient insulation, outer sheath breakage or inadvertent cutting of the outer surface by surgical instruments. Patients can suffer burns due to inefficient and uneven heat transfer to the surface area of the blankets.

"? OR temperature. The ambient temperature in the operating room should be kept between 68 ?F and 75 ?F, according to AORN. That can be an issue in many facilities where surgical team members lower the temperature as they work hard while gowned up under warm lights.

Early and often

Pre-warming patients in pre-op prevents hypothermia from setting in when anesthesia is administered. It also eliminates playing catch-up to reestablish normothermia in the OR.

Employing various warming techniques in combination optimizes your efforts to maintain normothermia, according to Dina Velocci, DNP, CRNA, owner of Velocci Anesthesia Services in Nashville, Tenn. "The biggest thing is to not rely on only one method to warm patients," she says.

Maintaining normothermia shouldn't hamper the surgeon's access to the surgical site, points out Dr. Velocci. When deciding which warming method to use, consider the type of case, the position the patient will be in, and the incision size and location. During abdominal cases, for example, it might be best to use forced-air upper-body blankets or a warming underbody mattress.

Says Dr. Velocci, "The more surface area of the patient you can cover and warm, the better outcomes you're going to have in maintaining normothermia." OSM