Temperature Measurement Sites Research Articles

Esophageal, Tympanic, Rectal, and Skin Temperatures in Children Undergoing Surgery With General Anesthesia

The purpose of this study was to determine the degrees of agreement between various sites of temperature measurement and examine the trend of body temperature in children during surgery under general anaesthesia. Thirty-six consecutive children who underwent surgery with general anaesthesia, had temperatures measured at the oesophagus, skin, ear canal and rectum at baseline, every 15 minutes for the first hour and every 30 minutes thereafter. Spearman correlation and Bland-Altman analyses were used to compare data and trends of mean differences assessed by line graphs. The median age of the sample was 48 months. There were 575 temperature measurements taken. The inter-method correlation coefficients was highest for the oesophageal vs rectal (r = 0.96) temperature and lowest for rectal vs skin (r = -0.11) temperature. The lowest mean difference (95% CI) in temperature at commencement of surgery was between the oesophageal and rectal sites, -0.03°C (-0.08, -0.01) while the highest mean difference (95% CI) temperature was between oesophageal and skin sites, 3.24°C (2.65, 3.85). The trend in differential temperatures between sites remained throughout the duration of surgery. Bland-Altman plots showed that the least difference (bias) at baseline (0.3°C) was between the oesophageal and tympanic temperatures while at 1 hour (0.13°C ) was between the oesophageal and rectal temperatures. The oesophageal site was the closest to rectal for monitoring core temperature while the skin was the least reliable site in the study population. In the situation where oesophageal probe is not routine or functioning, rectal or tympanic temperatures may be used.

Temperature management of patients with sepsis and inflammation in Australian and New Zealand ICUs: a point prevalence study

The use of pharmacological and physical antipyretic therapies to reduce fever in febrile patients is common in hospital settings. Actual evidence on the frequency of antipyretic use is limited, however, both in general hospital populations and, more specifically, in adult intensive care [1-3]. We undertook a prospective point prevalence study with the aim of identifying the prevalence of physical and pharmacological antipyretic therapies in intensive care patients with sepsis and inflammation. We also recorded the indication for antipyretic therapies, temperature measurement site, and mean temperatures on the study day.

A systematic review of body temperature variations in older people

The purpose of this systematic review was to determine the extent to which the research literature indicates body temperature norms in the geriatric population. The specific questions addressed were to examine normal body temperature values in persons 60 years of age and older; determine differences in temperature values depending on non-invasive measurement site and measurement device used; and, examine the degree and extent of temperature variability according to time of day and time of year. The traditional 'normal' temperature of 98.6 degrees F/37 degrees C may in fact be lower in older people due to the ageing process. Age-associated changes in vasomotor sweating function, skeletal muscle response, temperature perception and physical behaviours may influence the ability to maintain optimum temperature. A systematic literature review. A search of multiple databases yielded 22 papers which met inclusion criteria. Studies were included which focused on temperature measurement, sampled persons 60 years of age and older, collected data from non-invasive temperature measurement sites and which used a prospective study design. Studies were independently appraised using a structured appraisal format. Temperature normal values by site were rectal 98.8 degrees F/37.1 degrees C, ear-based 98.3 degrees F/36.8 degrees C, urine 97.6 degrees F/36.5 degrees C, oral 97.4 degrees F/36.3 degrees C and axillary 97.1 degrees F/36.2 degrees C. Temperature exhibited a 0.7 degrees F/0.4 degrees C diurnal and 0.2 degrees F/0.1 degrees C circannual variation. Synthesis of data indicated that normal body temperature values in older people by sites were rectal 0.7 degrees F/0.4 degrees C, ear-based 0.3 degrees F/0.2 degrees C, oral 1.2 degrees F/0.7 degrees C, axillary 0.6 degrees F/0.3 degrees C lower than adults' acceptable value from those traditionally found in nursing textbooks. Given the fact that normal body temperature values were consistently lower than values reported in the literature, clinicians may need to re-evaluate the point at which interventions for abnormal temperatures are initiated.

The effects of measurement site and ambient temperature on body temperature values in healthy older adults: A cross-sectional comparative study

Background Accurate baseline body temperature measurement is essential for assessment. Tympanic membrane temperature (TMT) measurement is popular, but there is no consensus on whether it is as accurate as oral temperature (OT) for use with the elderly at varying ambient temperature levels. Objectives To test agreement between TMT and OT measurement of body temperature among an elderly population; and to explore whether agreement between the two sites depends on ambient temperature. Design A cross-sectional comparison study. Methods Two samples of older community-dwelling adults were recruited from 17 community senior citizen centers in Taipei, Taiwan in winter ( n = 262) and summer ( n = 257) of 2007. TMT and OT were simultaneously measured by electronic infrared ear thermometer and electronic digital thermometer. Ambient temperatures measured by digital thermo-hygrometer of the data collection setting were recorded when body temperature was taken. Results In winter mean TMT was 36.64 °C (S.D. 0.37), and mean OT was 36.74 °C (S.D. 0.18). In summer, the mean TMT was 37.05 °C (S.D. 0.30) and mean OT was 36.85 °C (S.D. 0.22). The relationship between TMT and OT were r = 0.42 ( p < 0.001) in winter and r = 0.57 ( p < 0.001) in summer. The values of OT were used as standard to assess the accuracy of the measurement. The bias between TMT and OT was −0.10 °C (S.D. 0.34) and 95% limits of agreement were 0.57 and −0.77 °C in winter; and bias was 0.20 °C (S.D. 0.25) and 95% limits of agreement were 0.69 and −0.29 °C in summer. The findings of this study demonstrate that the TMT has high variability that may under or over estimate body temperatures. Conclusions There is a lack of agreement in body temperatures values between TMT and OT in community-dwelling elderly in both winter and summer. OT was more stable than TMT regardless of ambient temperature influences. Therefore, the oral cavity is preferable to the TM site for temperature measurement in alert elderly. The limitation of this study is that hospitalized patients who are most likely to need temperature measurement are not included in this study.

Exercise‐induced hyperthermia in childhood: a case report and pilot study

Hyperthermia is characterized by an increase of body core temperature due to exogenous heat exposure and/or endogenous heat production. Contrary to fever the hypothalamic-controlled temperature set point remains unchanged. To demonstrate that exercise-induced hyperthermia is a common phenomenon in childhood. We describe a 5-year-old boy, who attended our outpatient clinic with a 6-month observation period of exercise-induced hyperthermia with rectal temperatures up to 39.0 degrees C. Characteristically temperature dropped to normal values after cessation of exercise. In eight children aged 5-8, tympanic and rectal temperatures were measured before and after exercise. The rectal temperature increases frequently after exercise (p < 0.001), whereas tympanic temperature did not (p = 0.2). Benign hyperthermia should be considered in children with increased body temperature of unknown sources. The site of temperature measurement might be critical in the identification of this condition.

Abstract P136: Tracheal Temperature for Monitoring Core Temperature during Mild Hypothermia in Pigs

Purpose of the stud y: Early out-of-hospital induction of mild hypothermia after cardiac arrest needs an easy to use and accurate core temperature monitoring, which might be achievable with tracheal temperature measurement. The aim of the study was to evaluate which tracheal temperature site (Ttra) reflects best pulmonary artery temperature (Tpa) during the induction of mild hypothermia. Methods: Eight pigs (29 –38 kg) were anesthetized and intubated with a specially designed endotracheal tube with three temperature probes: Ttra1 was attached to the wall of the tube, 1 cm proximal to the cuff-balloon, without contact to the mucosa; Ttra2 and Ttra3 were placed on the cuff-balloon with tight contact to the mucosa, whereas Ttra3 was covered by a plastic tube to protect the mucosa. Core temperature was measured with a pulmonary artery catheter (Tpa). Pigs were cooled with a new surface cooling device (Emcoolspad®, Vienna, Austria). Data are presented as mean (±SD), and mean differences (95% CI). Results: Emcoolspad® decreased Tpa from 38.5°C to 33°C in 31±10 min, which translates into a cooling rate of 11.9±3.8°C/h. Overall mean differences of tracheal temperatures to pulmonary artery temperature (Tpa) are shown in table 1 . Ttra 1 showed the least difference to Tpa, followed by Ttra 2 and Ttra 3. There was a significant difference in temperature differences (Ttra-Tpa) related to temperature measurement site on the tracheal tube (p&lt;0.007). Conclusions: The temperature probe proximal of the cuff (Ttra 1) reflects best pulmonary artery temperature. It seems to be an accurate surrogate for core temperature during the induction of mild hypothermia. The industry is asked to provide a tracheal tube with a temperature sensor for simple temperature monitoring during fast cooling to facilitate the implementation of mild hypothermia after cardiac arrest in the out-of-hospital setting.

The vexatious problem of the variation of the phyllochron in wheat

Measurements of the thermal phyllochron in wheat using air temperature show a systematic variation with sowing date, with long phyllochrons for crops sown in autumn and winter, but shorter phyllochrons for sowings outside that range. Based on the hypothesis that the phyllochron is constant, two sources of error for the apparent variation in phyllochron are investigated, namely the site of temperature measurement (air or soil) and the implicit assumption that leaf appearance rate responds linearly to temperature. Measurements of the phyllochron from three sowings per annum for 6 years, from controlled environments, and from a sequence of sowings through an annual cycle are presented. The field results show similar systematic variation to that found elsewhere. However, for the annual cycle, calculations of the phyllochron based on soil temperature at 2 cm depth were much more stable than those based on air temperature. In addition, leaf appearance rate was linearly related to 2 cm soil temperatures across all environments, with a 0 °C intercept, and the optimum temperature was still not reached in the highest temperature treatment (30.9 °C soil temperature). Following earlier published work, we then show that the assumption that the phyllochron is constant, but that the controlling temperature at the apex is different from air temperature, requires a correction of less than 1 °C when sowing dates do not stray too much outside the range of normal practice. We show that the correction to air temperature is systematically related to sowing date, and a suitable correction can be made by using daylength some time after emergence as a predictive surrogate for seasonal variation in the air–apex temperature difference. We suggest that a model using such a predictor will improve predictions of leaf appearance rate over earlier functional models. However, we suggest that the observed response is caused by the physics of the system rather than the biology.

Documentation of Uncertainties and Biases Associated with Surface Temperature Measurement Sites for Climate Change Assessment

The objective of this research is to determine whether poorly sited long-term surface temperature monitoring sites have been adjusted in order to provide spatially representative independent data for use in regional and global surface temperature analyses. We present detailed analyses that demonstrate the lack of independence of the poorly sited data when they are adjusted using the homogenization procedures employed in past studies, as well as discuss the uncertainties associated with undocumented station moves. We use simulation and mathematics to determine the effect of trend on station adjustments and the associated effect of trend in the reference series on the trend of the adjusted station. We also compare data before and after adjustment to the reanalysis data, and we discuss the effect of land use changes on the uncertainty of measurement. A major conclusion of our analysis is that there are large uncertainties associated with the surface temperature trends from the poorly sited stations. Moreover, rather than providing additional independent information, the use of the data from poorly sited stations provides a false sense of confidence in the robustness of the surface temperature trend assessments.

Interrelationship between thermal imaging data and dairy traits in red-and-white cows

The aim of the research was the thermal imaging comparative analysis of milk production traits such as: CFU (number of micro-organism forming colonies ?1 cm-3 of milk), somatic cells count - SCC, content (%) of fat, protein, lactose, DM, no fat dry matter - NFDM and urea (mg?100 cm-3) and the skin temperature at the selected sites on a cow?s body. The research was conducted on 32 cows of Red-and-White breed, with an average milk yield 6797 kg per cow. On two sides of the body (left and right) two fixed temperature measurement sites on the joints (ankle joint, carpal joint) and 3 sites on the mammary glands (fore quarter teat cistern, hind quarter teat cistern and central ligament) were chosen as well as isotherm was drawn for the temperature distribution along the oblique body axis to record the minimal and maximal skin temperatures. Two sessions of thermal imaging photography 4 to 5 hours after morning milking were completed. An analysis demonstrated that the minimum temperatures along oblique body axis of clinically healthy cows measured on left body side relate with SCC (r = - .788; P? 0.05) and milk fat and DM contents (r = +.428 and r = +.450; P? 0.05). Temperature of the skin covering udder central ligament was related negatively with % content of milk fat and protein (r = -.438 and r = -.442; P?0.05 - for the left body side).

The vagaries of ear temperature assessment

There have been a growing number of reports suggesting that ear temperature measurement is unreliable and by implication so is the device. Examination of the measurement site, the tympanic membrane (eardrum) and the walls of the external auditory meatus (ear canal) reveals that at least some of the unreliability might derive from poor aiming of the infrared thermometer: the ear canal walls have a lower temperature than the eardrum. Additionally, anatomical properties of the ear canal may increase the difficulty of aiming the thermometer at the eardrum. Furthermore, the rich vascularization, innervation and variations in skin properties (thickness, oil secretion and hair) along the length of the ear canal affect the black body-like nature of the structure. It is concluded that such factors are more likely underlying reasons for the difficulties in reliably reproducing temperatures from this site. We conclude that concerns should extend beyond the reliability of the device and there should be greater study of the measurement site. The argument extends to all sites chosen for clinical assessment of the patient, as previous studies of the alternative temperature measurement sites are also unfortunately few and tend to be lacking in scientific rigour.

Cochlear temperature correlates with both temporalis muscle and rectal temperatures. Application for testing the otoprotective effect of hypothermia

Conclusions. During systemic hypothermia, the internal temperature of the rat cochlea correlates best with the temporalis muscle and rectal temperatures. These positive correlations will be used in future studies to assess the efficacy of mild and moderate hypothermia to protect hearing against the progressive loss caused by electrode insertion in a clinically relevant model of cochlear implantation trauma. Objective. To monitor the internal temperature of the cochlea during induced systemic hypothermia using a reference tissue instead of an internal cochlear temperature probe. Material and methods. The temperatures of the cochlea, brain, temporalis muscle and rectum were determined during periods of normothermia (37°C), mild (33°C) and moderate (30°C) hypothermia and slow rewarming in anesthetized adult Fisher rats. These values were compared using statistical analysis to establish the best correlations between the temperature of the cochlea and the temperature at the three other temperature measurement sites. Results. The strongest correlations with the internal temperature of the cochlea during the induction of mild-to-moderate hypothermia were obtained for the temperatures of the ipsilateral temporalis muscle and rectum.

Rectal Temperature Correction Overestimates the Frequency of Exercise-Induced Hypoxemia

Exercise-induced hypoxemia (EIH) occurs in an uncertain proportion of endurance trained athletes. Whereas blood gas measurements must be corrected for core temperature at the time of sampling, the commonly used rectal temperature readings may not be the most appropriate. Ten males [mean peak oxygen uptake, (.-)VO(2peak), 65.4 +/- 7.0 mL x kg x min] performed incremental treadmill exercise from rest to exhaustion with radial artery blood samples collected at the end of each 2-min workload for gas analysis. The thermogenic effect of exercise was monitored with rectal, arterial blood, and esophageal temperature probes, and the values obtained at all three sites, simultaneous with blood sampling, were used to correct the standard blood gas measurements made at 37 +/- C. The mean increase in rectal temperature across exercise (1.4 +/- 0.4 +/- C) was approximately half that recorded in radial arterial blood (2.3 +/- 0.5+/- C) and the esophagus (2.4 +/- 0.5 degrees C). In consequence, the uncorrected fall in PaO2 across exercise of 15.4 +/- 8.2 mm Hg was reduced to 8.4 +/- 7.7 mm Hg when corrected for rectal temperature, and to 2.9 +/- 7.4 and 2.1 +/- 8.8 mm Hg when corrected for arterial blood and esophageal temperatures. Using a fall of > or = 10 mm Hg as the index of EIH, the proportion in the 10 subjects in the present study fell from 80% (uncorrected) through 50% (rectal correction) to 20% (arterial blood and esophageal corrections). When correcting arterial blood gas values for the thermogenic effects of exercise, the proportion of athletes meeting the definition of EIH depends on the site of core temperature measurement.

Validation of Ear Canal Temperature Prediction Model for Core Temperature Monitoring

2146 Personal heat strain monitoring would be useful in preventing heat injuries due to uncompensable heat stress that occur during exercise in the heat. Ear canal temperature (Tec) can be used as a surrogate measure of core temperature (Tc) in occupational or military settings when the use of other temperature measurement sites is less appropriate. A personal heat strain monitor device has been developed for continuous telemetric measurement of Tc through the ear canal. In an earlier study, Tec measured during exercise in the heat were compared against rectal temperature (Tre), gastrointestinal temperature (Tgi), and a commercial ear temperature (Tac) probe. Preliminary results showed Tec to be a good indicator of Tc. Correction factors were then developed to predict Tc from Tec. PURPOSE: To validate the temperature prediction model developed in an earlier study. METHODS: N = 8 volunteers performed a heat stress protocol consisting of treadmill walking (4 km·h−1, 5% gradient) in a climatic chamber (35°C dry bulb, 70% rH, 600 W·m−2 simulated solar radiation, and 2 m·s−1). Tec and Tgi were measured continuously throughout the exercise. Participants exercised for an hour or until Tgi reached 39°C, whichever was earlier. RESULTS: The mean peak temperatures recorded were Tgi = 39.06°C ± 0.17°C, and Tec = 37.97°C ± 0.32°C. The recorded Tec showed a strong positive correlation with Tgi (r = 0.72) during exercise. When the two linear prediction equations developed in the earlier study were applied: Tc = Tec + 0.81°C, and Tc = 0.795Tphm + 8.507, the mean difference between Tgi and Tec was reduced to 0.07°C and 0.02°C respectively. CONCLUSIONS: Tec and Tgi had a linear relationship, and can be used as a good indicator of Tc during exercise. Although there is a mean error between recorded Tec and Tgi due to the difference in measurement sites, a linear correction would give readings in the range that clinicians and physiologists are familiar with interpreting.

Modeling Nutrient Upwelling in Lake Malawi/Nyasa

In response to a need for improved understanding of the nutrient budget for an African Great Lake, a field investigation of the physical and chemical limnology in Lake Malawi/Nyasa was undertaken. Continuous water temperature profiles at two stations along the longitudinal axis in the southern portion of the lake, shore-based winds, and frequent nutrient profiles at one of the temperature measurement sites provide the basis for a simple time dependent mathematical model of the vertical fluxes of six key nutrient species. Two components of nutrient flux are simulated, namely, the turbulent and the upwelling flux. Due to persistent southerly winds, vertically directed currents known as upwelling flows dominate the transport except near the surface where turbulent transport plays a role. On four occasions from May to August, 1997, AVHRR thermal imagery, nearshore winds, and longitudinal temperature transects demonstrated upwelling in the southern extremity of the lake. Thus, upwelling is responsible for the bulk of nutrient transport into the photic zone in the area studied. These results represent the first quantification of nutrient upwelling for a large African lake.

Monitoring Bladder Temperatures in the OR

Temperature monitoring via the urinary bladder has become common in the OR, often replacing monitoring at the rectal site. A systematic, integrated review and synthesis of the literature was undertaken to assess the validity of using the urinary bladder as a site for temperature measurement in the OR. During steady thermal states, bladder temperature performed well, providing temperatures similar to those of core sites. In contrast, poor performance was demonstrated during rapid thermal changes, such as during the rapid cooling and rewarming phases of cardiopulmonary bypass. At such times, a significant lag in response rate at the bladder site was noted by multiple investigators. This delayed responsiveness during thermally dynamic states, however, may provide information regarding the adequacy of rewarming during bypass at sites intermediate between the core and periphery. Limited research indicates that urinary bladder temperature may be influenced by urine flow rate, and additional research is required in this area. The cost effectiveness of this method of temperature measurement requires investigation as well.

The effects of phase control materials on hand skin temperature within gloves of soccer goalkeepers

In soccer, goalkeepers routinely wear gloves that may restrict heat loss from the hands and cause thermal discomfort. In order to alleviate this problem phase control materials (PCMs) have been incorporated into gloves to reduce heat load inside the glove, thereby maintaining a comfortable temperature. The aim of this study was to assess the efficacy of these materials during a simulation of goalkeeping activities. Seven subjects carried out two sessions of goalkeeperspecific exercise on a non-motorized treadmill, one session with a PCM glove and one session with a normal foam material glove (NFM). All sites of skin temperature measurement, except mean whole-body skin temperature, showed uniformly that the PCM glove caused a greater increase in skin temperature of the hand compared to the NFM glove. These results suggest that this particular specification of PCM promotes heat gain rather than heat loss and is therefore inappropriate to enhance thermal comfort in this setting.

Evaluation of mean skin temperature formulas by infrared thermography.

To study the reliability of formulas for calculating mean skin temperature (Tsk), values were computed by 18 different techniques and were compared with the mean of 10,841 skin temperatures measured by infrared thermography. One hundred whole-body infrared thermograms were scanned in ten resting males while changing the air temperature from 40 degrees C to 4 degrees C. Local, regional average and mean skin temperatures were obtained using an image processing system. The agreement frequency, defined as the percentage of the calculated Tsk values which agreed with the corresponding infrared thermographic Tsk within +/- 0.2 degree C, ranged for with the various formulas from 7% to 80%. In many sites, the local skin temperature did not coincide with the regional average skin temperature. When the local skin temperatures which showed the highest percentage similarity to the regional average skin temperature within +/- 0.4 degree C were applied to the formula, the agreement frequency was markedly improved for all formulas. However, the agreement frequency was not affected by changing the weighting factors from specific constants to individually measured values of regional surface area. By applying the physiologically reliable accuracy range of +/- 0.2 degree C in the moderate and +/- 0.4 degree C in the cool condition, agreement frequencies of at least 95% were observed in formulas involving seven or more skin temperature measurement sites, including the hand and foot. We conclude that calculation of a reliable mean skin temperature must involve more than seven skin temperature measurement sites regardless of ambient temperature. Optimal sites for skin temperature measurement are proposed for various formulas.

Inspired anaesthetic gas humidification improves thermal uniformity during canine whole body hyperthermia.

Supplying warmed saturated water vapour in anaesthetic gases during whole body hyperthermia (WBH) could potentially improve thermal uniformity in the trachea and esophagus. Four normal dogs were anaesthetized for WBH at 42 degrees C. A Puritan Bennett Cascade humidifier was used to supply anaesthetic gases saturated with water vapour at an average airway temperature of either 42 degrees C or 38 degrees C. Esophageal temperature was monitored at the thoracic inlet and 5 cm cephalad. Thermal dose was estimated by calculating equivalent minutes for an isoeffect at 43 degrees C (CEM 43 degrees Tx, where Tx is the site of temperature measurement). Endotracheal mucociliary transport velocity (MCTV) was determined before and 48 h following WBH by 99mTc-MAA scintigraphy. Compared to the 38 degrees C humidified gas group, dogs receiving 42 degrees C humidified gas reached 42 degrees C faster (p = 0.02) and had CEM 43 degrees T(esophageal) values equivalent to the target CEM 43 degrees T(rectal). Endotracheal MCTV with 42 degrees C humidified gas, however, was reduced 53% from baseline 48 h following WBH (p = 0.02). With 38 degrees C humidified gas, endotracheal mucociliary transport velocity was unchanged from baseline 48 h post WBH. Tracheal histology was examined using light and electron microscopy in four additional dogs euthanatized following 90 min of 42 degrees C humidified gas combined with WBH. There was no histological evidence of tracheal or lung thermal damage with 42 degrees C humidified gas in these four dogs. However, a moderate increase in tracheal goblet cell secretory granule staining was observed. This change could imply temporary heat-induced ciliary microtubule dysfunction, rather than decreased mucus production, as the likely mechanism of reduced mucociliary transport velocity 48 h following WBH. Administration of 42 degrees C humidified anaesthetic gases with WBH improves heating rate and esophageal thermal uniformity but temporarily depresses tracheal mucociliary transport velocity.

Ground temperature measurements in mountain permafrost, Jotunheimen, southern Norway

AbstractGround temperatures have been measured over a 5 year period of between −1.8 °C and −2.3 °C at 10m depth on a mountain plateau, 1851 m a.s.l. in Jotunheimen, southern Norway (61°40′N, 8°20′E). On the basis of additional shallow ground temperature measurements at different altitudes, the change in ground temperature with altitude is estimated to be 0.57 °C/100 m. This estimate, combined with the measured mean annual ground temperature, indicates the lower limit of discontinuous permafrost in the area to be at 1450–1500 m a.s.l. The mean annual ground temperature above 2200 m a.s.l. is below −4 °C. These values are representative for flat or slightly convex areas. Owing to strong winds, there is little snow until late April at the ground temperature measurement site. Maximum snow depth in May is 0.5 m.

The use of either the nose or outer ear as a means of determining the postmortem period of a human corpse

Presented in this paper are the initial results involving the use of the nose or outer ear as temperature measurement sites to determine the postmortem period of the human corpse. Simple mathematical models for both sites are developed based on cooling curves of five corpses. Analysis of errors between actual and calculated postmortem intervals suggest that in its present form, the described methods would not be suitable for use in accurately determining the time since death of human corpses.