How does perioperative temperature management improve patient outcomes?

In this article we will look at the concepts, the practices, and how effective perioperative temperature management improves patient outcomes. Moreover, we introduce some of the tools and solutions that can be applied in perioperative care routines to effectively manage temperature.

Temperature and its importance to health

Body temperature is one of our vital signs that are used to measure basic bodily functions. Keeping an eye on the vital signs can help detect and monitor medical problems. Body temperature is affected by a variety of parameters: It differs depending on e.g., age, gender, activity, surrounding temperature, and time of day. Conditions such as stress, infection, dehydration, sunburn and hormonal changes can also have an impact on body temperature.

The normothermic body temperature range is 36 to 37,5 °C. Hypothermia occurs when the body loses heat and the temperature drops below 35 °C. The opposite condition, hyperthermia, is an abnormally high body temperature. Forms of hyperthermia include heat fatigue, heat cramps and heat stroke. Both hypothermia and hyperthermia can be dangerous and potentially fatal conditions.

Perioperative temperature management

Perioperative temperature management refers to managing the patient’s body temperature throughout the perioperative phase, i.e. before, during and after surgery. Working with temperature management in relation to surgery is important, because anesthetics make the body lose heat and redistribute heat to peripheral parts of the body. This means there is a risk that the patient may become hypothermic. Hypothermia is a very common complication of surgery. Depending on the type of anesthetic agent used, as much as 50% of patients become hypothermic. For some patients however, fever can also be a risk factor that should be monitored and prevented, for example when it comes to patients with traumatic brain injury.

Preventing perioperative hypothermia is the main purpose of perioperative temperature management. Perioperative hypothermia is defined as a body temperature lower than 36 °C. It has several consequences including increased blood loss and increased risk of surgical site infections. Moreover, perioperative hypothermia delays the discharge from the post-anesthesia care unit. This means the patient cannot move on in the continuum of care and the hospital stay is extended.

From the perspective of the patient, perioperative temperature management has an additional purpose: Patients feel more comfortable when the temperature is comfortable. A study has found that when the patient’s needs for a comfortable temperature are met, then it increases the sense of calmness and well-being, and the patient feels more secure.

Three ways perioperative temperature management improves patient outcomes

Building on the above, we have summarized the results of effective perioperative temperature management in a top three: Increased patient comfort, improved healing of wounds, and faster recovery and discharge.

Increased patient comfort
It might sound obvious: Patients do not feel comfortable when they are freezing or feeling too warm. But there is more to it than that. Perioperative hypothermia can cause shivering which may increase post-operative pain. One of the aforementioned studies suggests that patients suffer in silence, when they are not able to influence their own temperature comfort. It also showed that coldness and warmth in connection with surgery was related to feelings of confidence about receiving the best care. There are more studies that support the general impact of temperature on patient comfort: One study suggests that the physical environment, including temperature, is a crucial factor related to patient comfort in the hospital. Put in other words, a comfortable temperature increases patient comfort.

Improved healing of wounds
Many factors can interfere with the healing of wounds. Perioperative hypothermia is one of them. It is a risk factor for wound infections, and it affects the immune system, reduces blood flow to the surgical site and impairs tissue oxygenation. All of which ultimately impair wound healing and prolong the hospital stay. On the other hand, a study has shown that significantly more collagen is deposited near the wound in normothermic patients after surgery compared to hypothermic patients. The normothermic patients in this same study also tolerated food and had sutures removed a day earlier than patients who suffered from perioperative hypothermia. To put it briefly, keeping patients normothermic helps them to heal better.

Faster recovery and discharge
When patients heal well, you can mobilize them quicker. This in turn means that they can get home faster, which is a win-win for both the patients and the hospital: Patients can leave the hospital setting, which for many people is an unfamiliar setting, and return sooner to the comfort of home. A well and fit patient is of course also the goal for healthcare personnel. Plus, hospitalizations come with costs, so a fast recovery and discharge also means reduced costs.

Solutions for managing and monitoring temperature

If you are looking to improve your perioperative temperature management practice with new workflows and tools, there are many to choose from for use both before, during, and after surgery.

The timing of temperature management
A study suggests that measures to prevent perioperative hypothermia should be initiated 1-2 hours before the anesthesia takes effect. Jessica Nilsson, Sales Manager at Medidyne, explains: “It is much easier and more effective to maintain normothermia than to treat hypothermia”. She continues: “Therefore, temperature management is very much a preventive practice that starts before the patient is sedated. When it comes to prewarming the patient, this should start at least 20-30 minutes before surgery.”

Methods and tools for warming
Overall, there are two methods for warming patients: Active and passive warming. Active warming is adding external heat to the patient. Passive warming is retaining the heat of the patient. Solutions for active warming include forced air warmers, heat mats, water mattresses, and radiant warmers. Solutions for passive warming include cotton blankets and reflective blankets and suits. Large volumes of intravenous and irrigation fluids may typically be used during surgery. Warming these can also help keep the patient warm. For burn patients esophageal or intravascular catheter solutions can be beneficial. The reason being that they warm the patient from the inside and out and hence do not get in contact with the burns.

Some of the solutions on the market can be used for both perioperative temperature management and targeted temperature management, which is also referred to as therapeutic hypothermia. Targeted temperature management is mainly used for cardiac arrest patients and patients with traumatic brain injury. For this application, a solution that can prevent shivering is valuable, as shivering can have a negative impact on the outcome.

Continuous monitoring
In order to know how to manage the patient’s temperature, you must monitor the patient’s temperature. A study suggests that proactive temperature monitoring should be applied in all phases of the perioperative care to enhance patient safety outcomes. There are different types of sensor solutions in the market that enable you to monitor body temperature from pre-operation to postanesthetic care unit.

What devices and solutions that are right for you and your department varies from another. But we have some general pieces of advice if you are looking to update your tools and practices in perioperative temperature management. Jessica says: “First and foremost, when it comes to temperature monitoring devices, is important to use the same device throughout the entire perioperative period. If you switch tools in the process, you cannot compare results.” She continues: “Generally you can say that it is important to measure and monitor temperature throughout the perioperative phase. Also, prewarming patients is important, and if you are giving fluid, it is very important that the fluid is warmed.”

Conclusion

Hypothermia is a common complication of surgery that can slow the patient’s healing and extend the hospital stay. Therefore, effective perioperative temperature management can be very beneficial to both patients and personnel: It increases patient comfort, improves the healing of wounds, and ultimately speeds up recovery and discharge from hospital.

There are a variety of methods and tools that can be applied in perioperative temperature management: You can use e.g. active or passive warming, and invasive or non-invasive methods. Plus, you can add a solution for temperature monitoring to check that the patient responds to the treatment and the body temperature stays within the desired range.