Core body temperature is a common biological constant, and its monitoring is accessible to everyone. It is systematically considered in numerous diagnostic investigations and patient follow-ups. As a vital health indicator, core temperature influences a wide range of biological processes, including metabolism, immune function and overall physiological homeostasis. Understanding and monitoring it are crucial for diagnostics, evaluating treatment effectiveness and ensuring patient safety, particularly in medical applications and healthcare applications.
Indicator of Health Status
The physiological mechanism that allows humans to maintain a constant temperature regardless of external conditions or internal heat production is called thermoregulation.
This process is controlled by the central nervous system, particularly the hypothalamus, through deep thermoreceptors (located in the viscera and transmitted via the bloodstream) and superficial thermoreceptors (located in the skin and transmitted via nerve pathways).
Thermoregulation is the balance between thermogenesis (heat production by the body) and thermolysis (heat loss by the body). Core body temperature is one of the primary vital signs assessed in clinical settings, alongside heart rate, blood pressure and respiratory rate. An abnormal core body temperature can indicate underlying health issues.
A normal core body temperature is referred to as normothermia. When thermoregulation is disrupted, temperature either rises (hyperthermia) or drops (hypothermia). Hyperthermia can result from increased heat production, high ambient temperatures, or reduced sweating (due to humid environments or inadequate hydration), without any hypothalamic regulation changes.
Fever, on the other hand, involves a shifted regulatory set point where the body maintains an elevated temperature due to decreased thermolysis and increased thermogenesis.
Fever is an abnormal increase in core temperature in response to infection, inflammation, or other pathological processes. Monitoring both the absolute temperature value and its variations over time is crucial for medical applications, enabling rapid and appropriate intervention. Normal resting temperature ranges between 36°C and 37.5°C, with fever generally defined as a temperature exceeding 38°C. Fever signifies the body’s immune response against pathogens.
Conversely, hypothermia, characterized by abnormally low core temperature, can result from cold exposure, medical conditions, or substance abuse and may lead to severe complications if not promptly treated.
Continuous core body temperature monitoring is essential for early detection of disorders, diseases, or complications in a patient’s condition. In emergency medicine, assessing core temperature aids in rapid decision-making regarding diagnosis and treatment. For instance, an elevated core temperature in a patient suspected of sepsis requires immediate interventions, including fluid resuscitation and antibiotic therapy.
Oncology Care
In chronic disease management, monitoring a patient’s core body temperature provides valuable insights into disease progression and treatment effectiveness.
In oncology, early detection of fever spikes is a critical challenge for chemotherapy patients, who are at high risk of febrile conditions such as aplastic anemia or febrile neutropenia. Fever is a frequent side effect of cancer treatments (lung cancer, breast cancer, prostate cancer, pancreatic cancer, etc.), typically caused by infections. Other causes include inflammation, drug reactions, or tumor growth, and sometimes the origin is unknown.
Fever is particularly critical when white blood cell levels are low or expected to decrease. During these periods, the body’s natural defenses are weakened, necessitating immediate evaluation. Fever can also be present in patients undergoing chemotherapy and/or biological therapy.
Real-time, continuous core body temperature monitoring enables early detection of fever spikes, significantly reducing response times for medical personnel.
Understanding and monitoring core body temperature is essential for diagnostics, assessing the effectiveness of treatments and patient safety, particularly in medical applications.
Infectious Diseases
Fever is a key indicator in infectious diseases, signaling the body’s fight against infection. A fever is defined as a core body temperature exceeding 38.3°C, while normal values range between 36.5°C and 37.3°C. Peripheral temperature (e.g., extremities) is typically 2 – 4°C lower than core temperature.
During infectious disease outbreaks, temperature monitoring is crucial, particularly during quarantine phases, allowing for early fever detection. Since fever is a fundamental diagnostic sign, rapid detection is essential for implementing early and appropriate therapy.
Automated, continuous temperature monitoring reduces intervention times, enhances diagnostic accuracy and improves patient comfort and care.
Surgical and Anesthetic Factors
Accidental perioperative hypothermia is a common anesthesia-related complication, increasing the risk of infections, bleeding and cardiovascular events, which can lead to higher perioperative mortality. Despite widespread preventive measures, perioperative hypothermia remains prevalent in France. In response, a panel of experts, under the French Society of Anesthesia and Intensive Care Medicine (Société Française d’Anesthésie et de Réanimation), issued recommendations aimed at improving prevention strategies.
Key expert recommendations include maintaining a core body temperature as close as possible to 36.5°C through appropriate warming techniques. Active skin warming techniques are recommended before and during anesthesia, as well as in post-operative recovery rooms. Additionally, warming intravenous fluids, blood products, and surgical fluids are advised to complement or substitute for external warming when necessary. Experts also emphasize the need to improve perioperative hypothermia detection by standardizing core body temperature monitoring.
Medication Effects and Pharmacokinetics
Core body temperature influences the pharmacokinetics and pharmacodynamics of medications. Temperature affects drug absorption, distribution, metabolism and excretion.
In clinical practice, understanding the relationship between core temperature and drug effects is crucial, particularly in elderly patients or individuals with impaired thermoregulation.
Improving Patient Care
In intensive care, real-time continuous core body temperature monitoring is vital for patientmanagement and immediate decision-making.
For instance, in patients with traumatic injuries or sepsis, accurate temperature tracking informs treatment protocols to stabilize hemodynamics and improve overall outcomes. Temperature monitoring is also crucial in post-operative patients to prevent complications.
Both local and general anesthesia can significantly lower core body temperature, potentially leading to moderate to severe hypothermia, depending on the case. This hypothermia is the result of 3 factors:
- Exposure to a cold environment,
- Suppression of thermoregulation by anesthetic agents,
- Negative heat balance (heat loss exceeding production).
Thermal Therapies and Rehabilitation
In rehabilitation medicine, core body temperature plays a crucial role in thermal therapies, including cryotherapy and hyperthermia treatments. Hyperthermia therapies are applied in cancer treatment to increase tumor sensitivity to radiation and chemotherapy.
Therapeutic heat also enhances collagen fiber elasticity, reduces muscle stiffness, relieves pain, and alleviates muscle spasms. Additionally, heat therapy helps reduce inflammation, swelling and accelerate healing.
By increasing blood flow to affected areas, heat delivers essential proteins, nutrients, and oxygen to facilitate healing. Heat-induced vasodilation improves oxygen and nutrient delivery while expelling carbon dioxide and metabolic waste.
Thermotherapy is used to treat muscle spasms, myalgia, fibromyalgia and cramps. It is also employed in cancer and infection treatment, as many cancer cells and bacteria struggle to withstand heat-induced physiological stress. For example, thermotherapy is used to treat retinoblastoma.
Thermotherapy is also used to treat migraines and headaches. Many people experience headaches combined with muscle pain in the neck and shoulders. By relaxing these muscles, thermotherapy helps reduce migraines. This medical technique is widely applied in aesthetic medicine, functional rehabilitation, sports medicine, and dermatology.
Enhanced core body temperature monitoring allows healthcare professionals to tailor these therapies to each patient’s needs, ensuring optimal effectiveness while minimizing risks.