Prevalence and Associated Factors of Perioperative Hypothermia among Surgical Patients at a Regional Referral Hospital in Eastern Uganda

When a person goes to the operating room, their body faces a silent challenge that has nothing to do with the disease being treated or the skill of the surgeon. Inside the operating theater, the complex machinery of human temperature control often shuts down. Anesthesia, the medicine that keeps patients asleep and pain-free, acts like a dimmer switch on the body's internal thermostat. It stops the brain from sensing cold and prevents the body from shivering or narrowing its blood vessels to hold in heat. At the same time, the surgery itself exposes warm internal organs to the cool air of the room, and the open skin acts as a window for heat to escape. This combination can cause a patient's core body temperature to drop, a condition known as perioperative hypothermia. While a slight chill might seem harmless, this drop in temperature is a serious medical concern because it can slow down healing, increase the risk of infection, and make it harder for the body to stop bleeding. In many parts of the world, especially in hospitals with limited resources, this preventable complication happens frequently, yet it is often overlooked because the tools to measure and fix it are not always available.

A team of researchers set out to understand exactly how often this happens and why, focusing their attention on a large regional hospital in eastern Uganda. They wanted to see the full picture of what occurs from the moment a patient enters the operating room until they wake up in the recovery area. The study took place at Mbale Regional Referral Hospital, a facility that serves millions of people and performs thousands of surgeries every year, ranging from emergency procedures to planned operations. At the time of the study, the hospital did not have a standard routine for checking patient temperatures, and the equipment to actively warm patients was scarce. The operating rooms were not air-conditioned, and the staff relied mostly on blankets provided by the patients' families to keep them warm after surgery. To get a clear view of the problem, the researchers followed 358 patients who were scheduled for surgery. They used a specialized thermometer that measures temperature through the ear canal, taking readings before the anesthesia started, during the operation, and immediately after the surgery ended. They defined hypothermia as any reading below 36.0 degrees Celsius, a threshold that marks the point where the body's safety systems begin to struggle.

The results revealed that this silent cooling was a common occurrence, affecting more than one-third of all the patients in the study. Specifically, 33.8 percent of the surgical patients developed hypothermia at some point during their care. The timing of the temperature drop was telling. While a small number of patients arrived at the hospital already slightly cool, the situation worsened significantly once the anesthesia took effect. The highest rate of hypothermia was observed one hour after the anesthesia was administered, when nearly one in five patients had dropped below the safe temperature limit. By the time patients reached the recovery area, the numbers had shifted, but the issue remained present for many. The researchers found that the risk was not spread evenly across all patients; instead, it was tied to specific characteristics of the person and the procedure. Older patients were more likely to become cold, as were those who underwent longer surgeries. The type of anesthesia also played a major role. Patients who received general anesthesia, which puts them fully to sleep, were much more likely to develop hypothermia than those who received regional anesthesia, which numbs only a specific part of the body while the patient remains awake.

Beyond the patient and the anesthesia, the environment and the length of the operation mattered greatly. The study showed that surgeries lasting longer than two hours carried a higher risk of causing hypothermia, likely because the body loses heat continuously over time. Interestingly, the temperature of the operating room itself was a factor. Surprisingly, the researchers found that patients were less likely to become hypothermic when the operating room was warmer, specifically above 30 degrees Celsius. This suggests that in a setting where active warming machines are rare, simply keeping the room temperature high could offer some protection. Conversely, the use of regional anesthesia was a strong protective factor, associated with a significantly lower chance of the body temperature dropping. The study also noted that very few patients received warmed intravenous fluids or were covered with active warming devices, highlighting a gap in the standard care available at the facility.

The findings from this hospital in Uganda paint a clear picture of a preventable problem that affects a large portion of surgical patients. The data suggests that the risk is highest for older adults, for those undergoing long procedures, and for those who are put under general anesthesia. While the study did not test specific treatments, it points toward practical steps that could be taken to improve safety. The researchers concluded that simply checking a patient's temperature before, during, and after surgery could help identify those at risk early. Prioritizing warming strategies for older patients and those having long operations could make a significant difference. The study also implies that in resource-limited settings, choosing regional anesthesia when medically appropriate might be a natural way to reduce the risk of hypothermia. Ultimately, the work underscores that keeping a surgical patient warm is not just a matter of comfort, but a critical part of safe medical care that can be managed with careful monitoring and simple, context-appropriate interventions.