Alarms don't sound and paramedics aren't called when a patient's core body temperature dips below 36 ?C, but the hidden consequences are no less serious than a life-threatening emergency. Warming patients properly prevents hypothermia, which helps reduce surgical site infections, the risk of impaired coagulation at the surgical site, hypertension and cardiac irritability. Here's a review of patient warming protocols.

Proactive approach
As a rule, you should start warming patients immediately in pre-op to avoid having to play catch-up later. Keeping patients warm throughout their stay is much easier than trying to raise the temperature of a shivering patient after a procedure.

When our patients enter pre-op, they sit on a chair covered by an already warmed blanket. Another warmed blanket is draped over their torso and lower extremities. After they enter the surgery suite, we wrap them in a third warmed blanket. For cases lasting longer than 30 minutes, we apply forced-air warming. After surgery, we reapply warmed blankets to patients as they recover.

Recognize patients who are at greater risk for becoming hypothermic and adjust your warming practices accordingly. Heavier patients tend to retain body heat thanks to their additional insulation, while slender patients, the very young or the elderly are particularly susceptible to becoming hypothermic because they lack that natural insulation.

Take a baseline temperature reading as soon as patients are settled in pre-op, monitor their temperatures in the OR and record a post-op reading in PACU. The SCIP Infection 10 measure mandates that all patients undergoing surgical procedures under general or spinal anesthesia be warmed using active warming and requires you to document at least 1 normothermic (36 ?C) temperature reading within 30 minutes prior to the delivery of anesthesia or 15 minutes after anesthesia administration has stopped.

In the OR, surgical teams draped in impervious gowns, masks and caps like to cool the rooms to offset the heat emitted from their bodies, the surgical equipment and lights. So maintaining patients' normothermia while they're anesthetized in cool surgical suites is just as important as doing so when they're able to complain about being cold. Forced-air warming is a popular and effective means for staving off hypothermia during surgery. The specialized blankets and gowns are easy to apply, allow for easy access to the surgical site and deliver consistent warming as they remain on patients throughout their perioperative stays.

While forced-air warming is largely safe to use, there are some inherent dangers associated with using the technology improperly. After applying a warming blanket or gown, make sure nothing rigid is applying pressure on the patient as this could cause the skin to blister. This should go without saying, but never use the hose of a forced-air warming unit without directing the heat through the system's specially designed gowns or blankets. Placing the hose underneath the patient's sheet — a dangerous practice called "free hosing" — can cause severe burns and is never an acceptable practice.

Forced-air warming systems are designed to deliver a constant flow of warmed air over the patient. The air that's blown by the heat pump through the system's hose and into the gown or drape must be allowed to escape after it passes over the patient. Look to see that the gown or blanket is inflated evenly throughout the procedure; areas that have flattened out are indications that air is not flowing through the system as it should. (A quick note: Be sure to place the heat pump where it or its cords won't pose as tripping hazards for the OR team. For us, situating the unit at the patient's head or foot on the opposite side of where the surgeon is standing works best.)

Read and react
Slight fluctuations between a patient's baseline temperature before surgery and the post-op reading are normal, but differences of more than a couple degrees (higher or lower) should be cause for concern.

In addition to the official temperature readings, don't ignore your instincts and what you see or feel as you're caring for patients. Touch a patient's neck or cheek as you're starting IVs before surgery or helping them dress in post-op. Are patients shivering or are their extremities cold? Oftentimes our "mom-o-meters" and nursing instincts work just as well as the latest temperature-taking technologies.

Keeping patients warm throughout their perioperative stay eases their anxieties, can reduce post-op pain perceptions and promotes faster, more efficient discharges. In the unlikely event that a patient becomes hypothermic, immediately and aggressively begin active warming techniques and closely monitor the patient's temperature until it reaches normothermia.