Changes In Cutaneous Temperature Research Articles

Infrared thermographic assessment of cutaneous temperature changes during labour epidural analgesia initiation: An observational pilot study

BackgroundInadequate labour epidural analgesia within 30––45 min of insertion is typically considered primary epidural failure and deemed unsuccessful. Early prediction of analgesic success would have clinical benefit, enabling corrective interventions. Sympathectomy accompanying a successful epidural block can cause foot temperature changes. We sought to evaluate the relationship between foot temperature changes and successful epidural, defined as adequate analgesia in 45 min of epidural administration. For the purpose of this study, we defined primary epidural failure as inadequate analgesia within 45 min of administration. MethodsFollowing ethical committee approval, this observational study was conducted in a tertiary level obstetric centre between January 2021 and March 2024. Patients attending for induction of labour were included; with labour epidural analgesia comprised the epidural study group and without acted as a control group. A FlirT540 infrared thermography camera was used to take bilateral foot images every 5 min for 30 min. Images were taken following epidural administration in the epidural group and at any convenient time once in established labour in the control group. We studied temperature changes over time in the epidural and control groups and compared the temperature changes in patients with successful and failed epidurals. ResultsThirty eight patients were included in the epidural group and eleven in the control group. 29 patients (76.3 %) had successful analgesia and 9 patients (23.7 %) had primary epidural failure. Patients with successful analgesia had a statistically significant rise in temperature after 10 min. The maximum rate of rise was between 5 and 15 min and was 0.5 (0.1)°C per minute on both sides. Primary epidural failure was associated with minimal temperature changes, while all patients who had a 2 °C rise in hallux temperature at 10 min had successful analgesia. ConclusionsSympathetic blockade associated with a successful analgesic epidural block produces cutaneous temperature elevation at the plantar surface of the hallux. These can be detected within ten minutes of instituting an epidural and have a potential role in guiding timely troubleshooting of an epidural.

Characterization of Baseline Temperature Characteristics Using Thermography in The Clinical Setting.

Thermography is a diagnostic method based on the ability to record infrared radiation emitted by the skin and is unique in its ability to accurately show physiological and/or pathological cutaneous temperature changes in a non-invasive way. This method can be used to indirectly assess changes or impairments in cutaneous perfusion. Significant technological advancements have allowed thermography to be more commonly utilized by clinicians, yet a basic consensus of patient characteristics that may affect temperature recordings is not established. We evaluated cutaneous temperature in a cohort of outpatients to understand what factors, including tobacco use and other high-risk characteristics, contribute to cutaneous tissue perfusion as measured by thermography. Participants were prospectively enrolled if they were a combustible cigarette smoker, an electronic cigarette (e-cigarette) user, or a never smoker. Standardized thermographic images of the subject's facial profiles, forearms, and calves were taken and demographic characteristics, medical comorbidities, and tobacco product use were assessed. These variables were statistically tested for associations with temperature at each anatomic site. We found that gender had a significant effect on thermographic temperature that differed by anatomic site, and we found a lack of significant difference in thermographic temperature by race. Our regression analysis did not support significant differences in thermographic temperatures across smoking groups, while there was a trend for decreased perfusion in smokers relative to non-smokers and e-cigarette users relative to non-smokers. Thermographic imaging is a useful tool for clinical and research use with consideration of sex and other perfusion-affecting characteristics.

Assessment of autonomic response in 6–12-month-old babies during the interaction with robot and avatar by means of thermal infrared imaging

ABSTRACT Since birth, infants have been immersed in a social environment, often surrounded by artificial-intelligent-agents (AIAs). However, there is a paucity of work on infants’ psychophysiological responses, and their related interest, when interacting with AIAs. Here, the infants’ psychophysiological responses during interactions with an embodied robot and a virtual human/avatar presented on a screen are investigated. The experimental paradigm consists of a robot producing socially communicative gestures to babies as compared to a virtual human producing socially communicative gestures and linguistic interactions, such as linguistic nursery rhymes in American Sign Language. Psychophysiological responses were measured using thermal infrared imaging technology that tracks changes in cutaneous temperature, enabling contactless investigation of human autonomic functions. Crucially, it permits first-time inferences about changes in infants’ psychological, attentional, and emotional engagement in relation to agents and events in the world around them. Thermal signals analysis revealed a statistically significant difference in the infants’ physiological response to robot and avatar interactions indicating important differences in each agent’s ability to engage infants. Understanding infants’ psychophysiological responses to AIAs during the first year of life, which is a crucial period for human learning, lays bare how AIAs may impact infants’ emotional, social, and language learning and higher cognitive growth.

Infrared thermographic assessment of spinal anaesthesia-related cutaneous temperature changes during caesarean section

IntroductionAssessment of adequacy of spinal anaesthesia, prior to obstetric surgery is extremely important but can be problematic because currently available clinical assessment methods are indirect and subjective. As the sympathectomy associated with spinal anaesthesia is known to cause vasodilation and heat redistribution, we sought to assess whether spinal anaesthesia led to significant and consistent cutaneous temperature changes as measured by infrared thermography. MethodsFollowing ethics committee approval, this observational study was conducted in a tertiary level obstetric centre. Participants included women undergoing elective caesarean section under spinal anaesthesia. Following consent, a Flir T540 infrared camera captured thermographic images over the feet, patella, buttock, iliac crests, xiphisternum and axilla. Temperature was measured prior to spinal needle insertion (T0) and following clinical assessment when the block was deemed adequate. ResultsThirty patients were included. Baseline temperature varied considerable by site. Spinal anaesthesia altered skin temperature in all areas of interest: right and left hallux (mean of differences (MD) +4.0°C and 5.2°C respectively, P <0.0001), right and left plantar (MD +6.1°C and 6.8°C respectively, P <0.0001), patella (MD −0.33°C, P=0.0445), buttock (MD −0.5°C, P=0.009), iliac crest (MD −0.7°C, P=0.0004), xiphisternum (MD −0.95°C, P <0.0001) and axilla (MD −0.71°C, P=0.0002). ConclusionsFollowing spinal anaesthesia thermographic imaging identified different patterns of skin temperature changes, with pronounced temperature increases measured in the feet and cooling of a lesser amplitude in the thoracic and lumbar dermatomes. Infrared thermography has the potential to provide objective measurement of sympathectomy.

Infrared Thermography Reveals Sex-Specific Responses to Stress in Mice.

Psychogenic hyperthermia is a stress-related condition reported mostly in women. Neuroendocrine responses to stress in females differ from those in males, and these differences cannot be explained solely based on hypothalamic-pituitary-adrenal (HPA) axis activity. Here, we used infrared (IR) thermographic imaging to record changes in cutaneous temperature following two types of stressful experiences in female and male mice. Mice were exposed to either single-session restraint stress or vertical exploration (rearing) deprivation and were monitored for exploratory activity and IR surface thermal changes. Females displayed higher rearing activity than males during the dark phase of the light cycle. Both sexes showed similar plasma corticosterone (CORT) responses after a challenge with restraint and rearing deprivation. However, only females responded to rearing deprivation with increased cutaneous temperature in the head and back, and a reduced thermal response in the tail. Circulating CORT levels were not correlated with the thermal variations. These findings, for the first time, provide evidence for sex-specific cutaneous thermal responses to short-term stress in mice following transient vertical-activity deprivation that may mimic clinical psychogenic hyperthermia.

Implementation of Wavelet Analysis on Thermal Images for Affective States Recognition of Children With Autism Spectrum Disorder

Children with Autism Spectrum Disorder are identified as a group of people who has difficulties in socio-emotional interaction. Most of them lack the proper context in producing social response through facial expression and speech. Since emotion is the key for effective social interaction, it is justifiably vital for them to comprehend the correct emotion expressions and recognitions. Emotion is a type of affective states and can be detected through physical reaction and physiological signals. In general, recognition of affective states from physical reaction such as facial expression and speech for autistic children is often unpredictable. Hence, an alternative method of identifying the affective states through physiological signals is proposed. Though considered non-invasive, most of the current recognition methods require sensors to be patched on to the skin body to measure the signals. This would most likely cause discomfort to the children and mask their “true” affective states. The study proposed the use of thermal imaging modality as a passive medium to analyze the physiological signals associated with the affective states nonobtrusively. The study hypothesized that, the impact of cutaneous temperature changes due to the pulsating blood flow in the blood vessels at the frontal face area measured from the modality could have a direct impact to the different affective states of autistic children. A structured experimental setup was designed to measure thermal imaging data generated from different affective state expressions induced using different sets of audio-video stimuli. A wavelet-based technique for pattern detection in time series was deployed to spot the changes measured from the region of interest. In the study, the affective state model for typical developing children aged between 5 and 9 years old was used as the baseline to evaluate the performance of the affective state classifier for autistic children. The results from the classifier showed the efficacy of the technique and accorded good performance of classification accuracy at 88% in identifying the affective states of autistic children. The results were momentous in distinguishing basic affective states and the information could provide a more effective response towards improving social-emotion interaction amongst the autistic children.

Post-mastectomy pain syndrome after mamma reduction plasty, an unusual case report

CRPS (complex regional pain syndrome) is well documented as a reflex sympathetic dystrophy. It mostly has been reported to occur in the extremities and has only been mentioned anecdotally in the breast after breast surgery or trauma of the chest wall. Recent literature describes a post-mastectomy pain syndrome (PMPS), which mimics CRPS symptoms and, despite the nomenclature, is not only limited to mastectomy procedures but also any other surgical procedure involving breast parenchyma. We report PMPS in a 39-year-old patient after revision operation of breast reduction surgery. Postoperatively, the patient showed symptoms of severe persistent pain, swelling, cutaneous temperature changes, and hyperhidrosis in the affected breast. Subcutaneous infiltration with triamcinolone acetonide and prilocaine only relieved the symptoms temporarily. Botox injections did not relieve her symptoms of sweating either. Two intercostal nerve branches were identified with ultrasonography and dissected in general anesthesia. This procedure relieved her symptoms. Surgeons should consider CRPS and PMPS as differential diagnosis of chronic disproportionate pain after breast surgery. Early identification and treatment will help alleviate persistent CRPS symptoms and avoid chronic soft tissue changes. Level of evidence: Level IV, diagnostic/therapeutic study.

INTRAOPERATIVE DIAGNOSIS OF NEUROLOGICAL COMPLICATIONS IN SURGERY OF SEVERE SCOLIOSIS: REPORT OF CLINICAL CASES

Clinical observations of 13- and 15-year-old patients with severe (118° and 133°) idiopathic scoliosis, subjected to operative correction with the use of segmental instrumentation are presented. Intraoperative monitoring of the spinal cord function was performed by recording motor potentials of the brain and skin thermometry from the lower limbs (authors’ technique). During the operation, there was a gradual decrease in potentials in one case and sharp in another, with no changes in cutaneous temperature. Based on the data of skin thermometry, surgeons decided not to remove the implant and to bring the operation to completion in both cases. In the postoperative period, neurological complications were not revealed. The conclusion is made about the advisability of including the skin thermometry in a complex of intraoperative monitoring of spinal cord function in patients with spine deformities.

Raphe obscurus neurons participate in thermoregulation in rats

In mammalian, several evidences suggest that central serotonin participates in thermoregulation. Nucleus raphe obscurus (NRO), a serotonergic nucleus, has been recognized to be the source of generation of various hemodynamic patterns in different behavioral conditions, but its involvement in thermoregulation is unclear. In the present study, extracellular action potentials of NRO neurons were recorded in anesthetized rats, which were submitted to cold and warm stimuli in the tail. The firing rate of the neurons was compared before and after each stimulation. It was found that 59% of the neurons submitted to a cold stimulus trial had a significant increase in their firing frequency, while 48% of the neurons submitted to warm stimulation trial were inhibited. The opposite responses in neuronal activity of NRO units to cooling or heating suggest that these cells are involved in producing the homoeothermic vascular adaptations secondary to changes in cutaneous temperature in the rat tail.

The application of infrared thermography in evaluation of patients at high risk for lower extremity peripheral arterial disease

We investigated the usefulness of infrared thermography in evaluating patients at high risk for lower extremity peripheral arterial disease (PAD), including severity, functional capacity, and quality of life. A total of 51 patients (23 males; age 70 ± 9.8 years) were recruited. They completed three PAD-associated questionnaires, including walking impairment, vascular quality of life, and 7-day physical activity recall questionnaires before a 6-minute walking test (6MWT). Ankle-brachial index (ABI) and segmental pressure were analyzed for PAD diagnosis and stenotic level assessment. The cutaneous temperature at shin and sole were recorded by infrared thermography before and after the walk test. Detailed demographic information and medication list were obtained. Twenty-eight subjects had abnormal ABI (ABI <1), while PAD was diagnosed in 20. No subjects had non-compressible artery (ABI >1.3). Demographic profiles and clinical parameters in PAD and non-PAD patients were similar, except for age, smoking history, and hyperlipidemia. PAD patients walked shorter distances (356 ± 102 m vs 218 ± 92 m; P < .001). Claudication occurred in 14 patients, while seven failed in completing the 6MWT. The rest temperatures were similar in PAD and non-PAD patients. However, the post-exercise temperature dropped in the lower extremities with arterial stenosis, but was maintained or elevated slightly in the extremities with patent arteries (temperature changes at sole in PAD vs non-PAD patients: -1.25 vs -0.15°C; P < .001). The exercise-induced temperature changes at the sole were not only positively correlated with the 6MWD (Spearman correlation coefficient = 0.31, P = .03), but was also correlated with ABI (Spearman correlation coefficient = 0.48, P < .001) and 7-day physical activity recall scores (Spearman correlation coefficient = 0.30, P = .033). By detecting cutaneous temperature changes in the lower extremities, infrared thermography offers another non-invasive, contrast-free option in PAD evaluation and functional assessment.

"MOOD RINGS": A NEW METHOD OF OBJECTIVE CLINICAL ASSESSMENT OF PERIPHERAL NERVE INJURIES

The clinical assessment of patients with peripheral nerve injury is primarily dependent on subjective clinical examination. We aimed to assess whether a thermotropic liquid crystal ring (TLC-ring) could provide the basis for an objective assessment of peripheral nerve injury by detecting temperature changes in the digits innervated by the damaged nerve. A group of patients with known median, ulnar or both digital nerve injuries were compared against a control group. TLC-rings, marketed to the general public as "mood rings", were applied to the affected and unaffected digits and the colour change recorded. Areas with nerve damage showed a statistically significant difference in colour response to those without damage. This study establishes the ability of TLCs to detect cutaneous temperature changes associated with peripheral nerve injuries. Further studies and improvements are needed to refine TLC as an acute assessment tool for peripheral nerve injuries.

Changes in cutaneous and body temperature during and after conditioned fear to context in the rat

Infrared thermography was used to image changes in cutaneous temperature during a conditioned fear response to context. Changes in heart rate, arterial pressure, activity and body (i.p.) temperature were recorded at the same time by radio-telemetry, in addition to freezing immobility. A marked drop in tail and paws temperature (-5.3 and -7.5 degrees C, respectively, down to room temperature), which lasted for the entire duration of the response (30 min), was observed in fear-conditioned rats. In sham-conditioned rats, the drop was on average half the magnitude and duration. In contrast, temperature of the eye, head and back increased (between + 0.8 and + 1.5 degrees C), with no difference between the two groups of rats. There was a similar increase in body temperature although it was slightly higher and delayed in the fear-conditioned animals. Finally, ending of the fear response was associated with a gradual decrease in body temperature and a rebound increase in the temperature of the tail (+ 3.3 degrees C above baseline). This study shows that fear, and to some extent arousal, evokes a strong cutaneous vasoconstriction that is restricted to the tail and paws. This regionally specific reduction in blood flow may be part of a preparatory response to a possible fight and flight to reduce blood loss in the most exposed parts of the rat's body in case of injury. The data also show that the tail is the main part of the body used for dissipating internal heat accumulated during fear once the animal has returned to a safe environment.

Sleep propensity is modulated by circadian and behavior-induced changes in cutaneous temperature

A close relation between sleep and body temperature has been noted already for a long time. Although a correlation is indisputable, there is at present hardly evidence for a causal involvement of sleep in changes in body temperature. Concerning the reverse, a causal involvement of body temperature in sleep has been demonstrated: if core or skin temperature changes activate thermoregulatory processes aimed at heat loss or heat preservation, sleep is usually disrupted. We have recently proposed that sleep propensity is also affected by more subtle changes in skin temperature, within the thermoneutral range (Van Someren (2000). Chronobiol. Int. 17, 313–354). These changes are likely to modulate the firing properties of thermosensitive neurons in brain areas involved in sleep regulation. Subtle changes in skin temperature occur daily under control of the circadian timing system. They could provide this system with an additional signal pathway to support its neuronal and neurohormonal signals to enforce circadian modulation of sleep propensity. Subtle changes in skin temperature also result from behavior, and could contribute to the changes in sleep propensity resulting from these behaviors. The present review summarizes the neurobiological background and correlational physiological and behavioral data in support of the involvement of skin temperature in the modulation of sleep propensity. It moreover points out the type of experimental investigations needed to support or refute the hypothesis.

Assessment of sympathetic blocks

Sympathetic nervous system blockade provides both diagnostic and therapeutic potentials in certain chronic pain states. Sympathetically maintained pain associated with complex regional pain syndrome and chronic intractable abdominal or pelvic pain are perfect examples for such conditions. Because pain relief is a subjective phenomenon, it is important to establish an objective way of assessing the success of the sympathetic blockade. This report will discuss various tests of sympathetic function that could be used in clinical practice. Special emphasis in this report will be on changes in cutaneous temperature, blood flow, provocative sweat tests, and electrical skin conduction as indicators of sympathetic function. Copyright © 2001 by W.B. Saunders Company

Comparison of lower extremity cutaneous temperature changes in patients receiving lumbar sympathetic ganglion blocks versus epidural anesthesia

Study Objective: To investigate if paravertebral lumbar sympathetic ganglion block and lumbar epidural anesthesia result in comparable cutaneous temperature changes in the lower extremity. Design: Nonrandomized comparison study. Setting: Operating rooms and pain clinic procedure rooms in a tertiary care hospital. Patients and Interventions: 18 patients undergoing lumbar sympathetic ganglion blocks for the diagnosis and/or treatment of chronic pain, and 13 patients undergoing lumbar epidural anesthesia for radical prostatectomy. Measurements: Cutaneous temperatures were measured over the great toe, calf, and thigh in all patients. Mean maximum temperature (Tmax), rate of change of skin temperature (from 5% to 95% of maximum temperature change), and mean time to 1°C increase, and 50% and 95% of maximum temperature change for each group were compared. Temperature changes for the epidural and lumbar sympathetic block patients were compared. Main Results: Epidural and lumbar sympathetic block resulted in similar Tmax (34.1 ± 0.2 and 33.8 ± 0.9°C, respectively, mean ± SEM; p = 0.18) and rate of temperature change (0.64 ± 0.09 and 0.49 ± 0.07°C/min; p = 0.2) in the great toe. The onset of cutaneous temperature change after lumbar sympathetic block was slower than after epidural anesthesia (1°C increase: 17 and 11 min, respectively, 50% of Tmax: 25 and 17 min, respectively, and 95% of Tmax: 40 and 31 min, respectively; p < 0.05 for each). Conclusions: The similar rate and magnitude of cutaneous temperature change in the distal lower extremity suggests the degree of sympathetic blockade is similar with lumbar sympathetic blockade and epidural anesthesia. Either technique should provide adequate sympathectomy for treating sympathetically maintained pain once the diagnosis has been confirmed using selective sympathetic blockade.

前庭自律神経反射及び体性自律神経反射系のＡｄａｐｔａｔｉｏｎについて

Cutaneous temperature changes and subjective sensations concomitant with repeated caloric and metopic cooling stimuli were studied quantitatively in order to observe the adaptation of the vestibular autonomic reflex system and the somatic autonomic system response.The subjects were 17 healthy adults. Stimuli were applied three times at intervals of 6 minutes. The caloric stimulus consisted of exposing the right ear at 50°C for 60 seconds, while the metopic cooling stimulus consisted of applying an ice pack to the metopic region for 30 seconds. Subjective sensation was quantified during caloric stimulation by scoring vertigo and nausea on a six-grade scale and emesis on a two-grade scale. These scores were then totaled. During metopic cooling, stimulation by scoring cold sensations in the metopic region was on a six-grade scale.When caloric stimulation was applied, lowered sensory scores were associated with significantly decreased cutaneous temperature variation and slow-phase velocity. Conversely, no significant changes in either cutaneous temperature variations or sensory scores were recognized when metopic cooling stimulation was applied.These results indicate that the loci of central adaptation mechanisms, including the vomiting centers, are largely involved as sites responsible for adaptation in the vestibular autonomic reflex system.

Correlation of hippocampal theta rhythm with changes in cutaneous temperature.

Investigation of the possibility that the hippocampus performs the function of alerting an animal to changes in cutaneous temperature, using unanesthetized, loosely restrained rabbits. The results indicate that the hippocampal theta rhythm, which appears to be evoked by changes in cutaneous temperature, can be related to a specific type of hyppocampal neuron which is, in turn, connected with other areas of the brain involved in temperature regulation.

Spinal neurons specifically excited by noxious or thermal stimuli: marginal zone of the dorsal horn.

HIGH-THRESHOLD MECHANORECEPTORS and their centrally projecting myelinated fibers make up a functionally distinct group of cutaneous sensory units that have been suggested as part of the afferent apparatus for pain resulting from mechanical damage to the skin (3, 17). The argument for their relation to pain was based on two points: 1) the ability of such afferent elements, unique among those with medullated fibers, to provide signals differentiating noxious from innocuous mechanical events affecting the skin; and 2) the well-established correlation between pain and activity in thin myelinated afferent fibers

Cord cells responding to touch, damage, and temperature of skin.

Cord cells responding to touch, damage, and temperature of skin.

An evaluation of the ability of priscoline, regitine, and roniacol to overcome vasospasm in normal man; estimation of the probable clinical efficacy of these drugs in vasospastic peripheral vascular disease.

This paper is a study of the comparative efficacy of Priscoline, Regitine, and Roniacol in relaxing vasospasm in the extremities of normal human subjects. A total of 60 studies were performed on 14 subjects. Severe cutaneous vasospasm was induced by exposure of the lightly clad subject to an environmental temperature of 20 C. for one hour or more. In half the tests the severe vasospasm was reduced to moderate vasospasm by application of heat to the torso of the chilled subjects. The effectiveness of the drugs was tested by giving them by intravenous infusion after the appropriate state of vasospasm had been obtained. The degree of relaxation of vasospasm was estimated from the resulting changes in cutaneous temperature recorded with thermocouples.