Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “SHIVERING”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 829 records · Page 46Linked to original sources

Side effects of oral misoprostol during the first 24 hours after administration in the third stage of labour.

OBJECTIVE: To evaluate the side effects of 600 microg misoprostol orally during the first 24 hours after administration in the third stage of labour. DESIGN: Double blind randomised controlled trial. SETTING: Tertiary care hospitals in Nigeria and Thailand. SAMPLE: All women participating in the WHO Misoprostol trial in these two hospitals between January 1, 1999 and June 17, 1999. METHODS: All women were followed up during the first 24 hours postpartum to evaluate the occurrence of shivering, nausea, vomiting, diarrhoea and other misoprostol-related side effects. MAIN OUTCOME MEASURES: Rates of shivering, nausea, vomiting, diarrhoea and pyrexia within 1 hour and in the intervals 2-6, 7-12, 13-18 and 19-24 hours after delivery. RESULTS: A total of 1686 women were enrolled. Women who received misoprostol had higher incidence than the oxytocin group of 'any' shivering in the first hour (RR 6.4, 95% CI 3.9 to 10.4) and the period covering 2-6 hours following delivery (RR 4.7, 95% CI 1.9 to 11.2). Pyrexia was also more common in the misoprostol group in both the same time intervals (RR 2.8, 95% CI 1.4 to 5.3 and RR 6.3, 95% CI 3.7 to 10.8, respectively). Diarrhoea was not present in the first hour in either group but appeared in the second time period (2-6 hours) and third time period (7-12 hours) more frequently in the misoprostol group than with oxytocin. CONCLUSION: The increased incidence of shivering and pyrexia that occurs with postpartum use of misoprostol persists up to 6 hours following delivery. Approximately 5% of women experience diarrhoea that starts after 1 hour and subsides within 12 hours.

Administration, Oral↗

Active warming during cesarean delivery.

UNLABELLED: We tested the hypothesis that 15 min of forced-air prewarming, combined with intraoperative warming, prevents hypothermia and shivering in patients undergoing elective cesarean delivery. We simultaneously tested the hypothesis that maintaining maternal normothermia increases newborn temperature, umbilical vein pH, and Apgar scores. Thirty patients undergoing elective cesarean delivery were randomly assigned to forced-air warming or to passive insulation. Warming started 15 min before the induction of epidural anesthesia. Core temperature was measured at the tympanic membrane, and shivering was graded by visual inspection. Patients evaluated their thermal sensation with visual analog scales. Rectal temperature and umbilical pH were measured in the infants after birth. Results were compared with unpaired, two-tailed Student's t-tests and chi(2) tests. Core temperatures after 2 h of anesthesia were greater in the actively warmed (37.1 degrees C +/- 0.4 degrees C) than in the unwarmed (36.0 degrees C +/- 0.5 degrees C; P < 0.01) patients. Shivering was observed in 2 of 15 warmed and 9 of 15 unwarmed mothers (P < 0.05). Babies of warmed mothers had significantly greater core temperatures (37.1 degrees C +/- 0.5 degrees C vs 36.2 degrees C +/- 0.6 degrees C) and umbilical vein pH (7.32 +/- 0.07 vs 7.24 +/- 0.07). IMPLICATIONS: Perioperative forced-air warming of women undergoing cesarean delivery with epidural anesthesia prevents maternal and fetal hypothermia, reduces maternal shivering, and improves umbilical vein pH.

Adult↗

Effect of 5-hydroxytryptophan acting from the cerebral ventricles on 5-hydroxytryptamine output and body temperature.

1. In cats anaesthetized with intraperitoneal pentobarbitone sodium the third ventricle, the anterior or inferior horn of the left lateral ventricle, was perfused with 5-hydroxytryptophan (5-HTP) in different concentrations, and the effluent assayed for 5-hydroxytryptamine (5-HT) on the rat stomach strip preparation of Vane (1957).2. On perfusion of the third ventricle with 5-HTP the output of 5-HT in effluent increased, the increase depending on the 5-HTP concentration: with 1/50,000 it increased 44-69 times (mean 55), with 1/25,000, 81-83 times (mean 82) and with 1/10,000, 71-200 times (mean 128). The 5-HT output depended also on the initial output during the preceding perfusion with artificial c.s.f. The greater this initial output the greater was the maximum output reached during the 5-HTP perfusion.3. The increase in 5-HT output during perfusion of the third ventricle with 5-HTP was usually associated with shivering and a rise in rectal temperature. This association, however, was not invariably obtained, probably because of a central depressant effect of 5-HTP itself.4. On perfusion of the anterior or inferior horn of the left lateral ventricle with 5-HTP, the output of 5-HT in the effluent also increased, but to a lesser extent than in the effluent from the third ventricle. There was no association with shivering nor with a rise in rectal temperature.5. An injection of 1 or 2 mg 5-HTP into the cerebral ventricles of unanaesthetized cats produced a biphasic rise in temperature, shivering, constriction of the skin vessels followed by vasodilatation, tachypnoea, wiping and scratching movements, miaowing and long lasting sleep.6. The biphasic rise in temperature is explained as the result of two opposing effects: increased formation of 5-HT which would raise body temperature, and a central depressant effect of 5-HTP itself or of one of its metabolites which would lower body temperature.7. The initial rise in temperature and the shivering in response to an intraventricular injection of 5-HTP varied from cat to cat. In those in which these effects were strong the 5-HT output during a subsequent perfusion of the third ventricle with artificial c.s.f. was higher, and the maximum 5-HT output reached on perfusion with 5-HTP was greater than in those in which these effects had been weak.

5-Hydroxytryptophan↗

Experimental study of convective heat transfer coefficient for the human body in water.

The steady-state convective heat transfer coefficient in water has been determined by partitional calorimetry for 17 nude subjects. Four water velocities were investigated: 0, 0.05, 0.10, and 0.25 m-s-1; and the water temperature ranged from 33.7 to 18 degrees C. In still water, hc varied from 43 W-m-2-degrees C-1 in thermoneutral conditions and a shivering rate less than 90 W-m-2 to 54 W-m-2-degrees C-1 in cold water with a shiver rate greater than 110 W-m-2. The equation, hc=0.09 (Gr-Pr)0.275, give a good approximation of this coefficient. In stirred water and for the same limits of shivering, hc can be expressed as a power function of the velocity: hc = 272.9 v0.5 and hc = 497.1 v0.65, respectively. These equations show that the flow is laminar in thermoneutral conditions and intermediate between laminar and turbulent in cold water. A study of the influence of skinfold on the magnitude of hc shows that higher values of this coefficient were obtained for thin subjects than for fat ones, concomitant with more intense shivering. The utilization of a theoretical physical model for computations of hc gave excessively high values because such methods do not embody the body shape factor and reduction of water flow adjacent to the skin.

Adipose Tissue↗

Thermogenic control during exercise in a cold environment.

To determine whether the voluntary contractions of exercise interfere with involuntary shivering contractions, four male subjects were each exposed to a 10 degrees C environment for 60 min of rest followed by either another rest period or 30 min of cycleergometer exercise. On different days exercise was performed at zero load, light load, and moderate load. Each experiment was performed twice, resulting in a minimum of eight experiments for each subject. Esophageal temperature (Tes), eight skin temperatures (Tsk), oxygen uptake (VO2), and the integrated electrical activity from a neck muscle (EMG) were continuously monitored. Pedaling flushed cold blood into the body core, causing Tes to fall. The rate and absolute magnitude of the decrease in Tes was proportional to the intensity of exercise. Thermoregulatory VO2 (attributable to shivering) and EMG were inversely related both to Tsk during rest, prior to any changes in Tes, and to Tes during exercise, when Tsk was constant, once shivering thresholds were surpassed. The slope of the thermoregulatory VO2-to-Tes relation was significantly suppressed by increasing exercise intensity. The slope of the EMG-to-Tes relation was similarly suppressed; since the neck muscles are not involved in the additional acitivity of exercise, we concluded that the graded inhibition of shivering during exercise was of central origin rather than from the rhythmic contractions required to sustain exercise.

Adult↗

Effectiveness of three field treatments for induced mild (33.0 degrees C) hypothermia.

Three field applicable treatments for hypothermia were compared. Subjects were cooled in stirred cold water (8.0 degrees C) to a core temperature (Tco) as low as 33 degrees C and rewarmed in a random order by each of three techniques: shivering, external heat, and treadmill exercise. Tco was monitored with an esophageal thermistor probe at the level of the heart. Treatment effectiveness was determined by calculating the amount of Tco afterdrop, length of afterdrop period, rate of Tco increase, and total recovery time. Rate of Tco increase for exercise (4.9 degrees C/h) was significantly higher (P less than 0.05) than shivering (3.5 degrees C/h) but not external heat (3.7 degrees C/h). Exercise afterdrop amount and afterdrop length values (0.95 degrees C and 24 min, respectively) were significantly higher (P less than 0.05) than both shivering (0.33 degrees C, 15 min) and external heat (0.32 degrees C, 14 min). Therefore, although rate of Tco increase during recovery for exercise was faster than for shivering or external heat, as it was preceded by a greater afterdrop length and amount, total recovery time did not differ among the three treatments.

Adult↗

A trial of therapeutic hypothermia via endovascular approach in awake patients with acute ischemic stroke: methodology.

BACKGROUND: Therapeutic hypothermia has been shown to be of benefit in improving neurological outcome in cardiac arrest. It now is being investigated in acute stroke and myocardial infarction. The majority of the literature describes its use in intubated, pharmacologically paralyzed patients, using surface cooling techniques that are susceptible to patient shivering, imprecise temperature control, time lag to target-temperature acquisition, and rebound hyperthermia. OBJECTIVES: To develop a method of inducing therapeutic hypothermia in a rapid, precise, and tolerable fashion in awake, nonintubated patients. METHODS: This method was developed for an ongoing clinical trial investigating a combination of therapeutic hypothermia and intravenous thrombolysis for acute ischemic stroke. In the protocol, an endovascular cooling device is placed in the inferior vena cava of a patient, and a combination of buspirone, meperidine, and cutaneous warming with a heating blanket is used to suppress shivering as the patient is cooled to a target temperature of 33 degrees C, kept there for a total of 24 hours from hypothermia initiation, and then rewarmed in a controlled fashion during the next 12 hours. RESULTS: Ten patients underwent the therapeutic hypothermia protocol. The median pretreatment core temperature was 36.1 degrees C (interquartile range [IQR]: 35.8 degrees C-36.4 degrees C). On initiation of cooling, the core temperatures dropped rapidly and then leveled off, approaching a median plateau value of 33.4 degrees C (IQR: 33.2 degrees C-33.9 degrees C) in a mean time of 1.7 (+/- 0.7) hours from cooling initiation, with a median average postplateau temperature during the cooling phase of 33.8 degrees C (IQR: 33.3 degrees C-34.6 degrees C), and a median lowest temperature of 33.1 degrees C (IQR: 33.0 degrees C-33.3 degrees C). The procedure was well tolerated, with minimal shivering and no rebound hyperthermia. CONCLUSIONS: This is a method by which a rapid and precise therapeutic decrease in core temperature can be achieved without the necessity for intubation or neuromuscular blockade and with minimal patient discomfort or shivering.

Adolescent↗

Chronic treatment with antidepressants decreases intraoperative core hypothermia.

UNLABELLED: We investigated temperature regulation during anesthesia and postoperative shivering in chronically depressed patients given antidepressant drugs. We studied 35 depressed patients and 35 control patients who underwent orthopedic surgery. Tympanic membrane temperatures 60, 75, and 90 min after induction in the depression group were significantly (P < 0.05) higher than those of the control group. There were no significant differences in mean skin temperature between the depression and the control groups. Eight of 35 patients in the depression group and 2 of 35 patients in the control group developed postanesthetic shivering. The incidence of shivering in the depression group was significantly more frequent than that in the control group (P = 0.04). The tympanic membrane temperature of the patients treated with clomipramine tended to be higher than that of the patients treated with maprotiline. In conclusion, intraoperative core hypothermia in chronically depressed patients was decreased. However, the incidence of shivering in depressed patients was significantly more frequent. IMPLICATIONS: Thermoregulation in chronically depressed patients is often altered. The alteration of body temperature is affected by depression itself and by antidepressants. General anesthesia has an influence on thermoregulatory control. However, temperature regulation during anesthesia in chronically depressed patients remains unclear.

Adult↗

Lasting effect of infantile cold experience on cold tolerance in adult rats.

The effect of short and repetitive exposure to cold (5 degrees C, 4 hr/day for 2 weeks) from the birth up to the 14th day of newborn rats onthe thermal regulation in adulthood and on the tolerance to cold was investigated. After being exposed to cold, they were transferred to a room at 25 degrees C (N-CA). The control rats were raised at 25 degrees C (N-WA). An acute cold exposure test was performed by placing the animals in a room at 5 degrees C under urethane anesthesia. Electrical activity of neck muscles as an index of shivering was recorded. The colonic temperature fell at a significantly slower rate in N-CA rats with less shivering than in N-WA ones. Nonshivering thermogenesis tested by norepinephrine was significantly greater in N-CA rats than in N-WA ones. These results suggest that N-CA rats developed improved cold tolerance accompanied by greater nonshivering thermogenesis. Such a phenomenon in N-CA lasted for 18 weeks after the termination of cold exposure. Adult rats subjected to the same scheme of cold exposure (A-CA) (5 degrees C, 4 hr/day, 2 weeks) showed essentially the same results as seen in N-CA, but its improved cold tolerance and elevated nonshivering thermogenesis disappeared 4 weeks after the termination of cold exposure. Extirpation of interscapular brown adipose tissue immediately before the cold test did not appreciably affect the cold tolerance in N-CA and A-CA rats. The colonic temperature at the onset of shivering was significantly lower in N-CA as well as A-CA rats than in each of the corresponding control rats, indicating a shift of the shivering threshold to lower temperature values in the animals exposed intermittently to cold. These results indicate that an infantile experience with cold results in a greater and longer sustained ability to tolerate cold in adulthood, characterized by enhanced nonshivering thermogenesis.

Acclimatization↗

Immersion of distal arms and legs in warm water (AVA rewarming) effectively rewarms mildly hypothermic humans.

INTRODUCTION: Active rewarming of hypothermic victims for field use, and where transport to medical facilities is impossible, might be the only way to restore deep body temperature. In active rewarming in warm water, there has been a controversy concerning whether arms and legs should be immersed in the water or left out. Further, it has been suggested in the Royal Danish Navy treatment regime, that immersion of hands, forearms, feet, and lower legs alone might accomplish rapid rates of rewarming (AVA rewarming). METHODS: On three occasions, six subjects (one female) were cooled in 8 degrees C water, to an esophageal temperature of 34.3+/-0.8 (+/-SD) degrees C. After cooling the subjects were warmed by shivering heat production alone, or by immersing the distal extremities (hands, forearms, feet and lower legs) in either 42 degrees C or 45 degrees C water. RESULTS: The post cooling afterdrop in esophageal temperature was decreased by both 42 degrees C and 45 degrees C water immersion (0.4+/-0.2 degrees C) compared with the shivering alone procedure (0.6+/-0.4 degrees C; p < 0.05). The subsequent rate of rewarming was significantly greater with 45 degrees C water immersion (9.9+/-3.2 degrees C x h(-1)) than both 42 degrees C water immersion (6.1+/-1.2 degrees C x h(-1)) and shivering alone (3.4+/-1.5 degrees C x h(-1); p < 0.05). CONCLUSION: The extremity rewarming procedure was experienced by the subjects as the most comfortable as the rapid rise in deep body temperature shortened the period of shivering. During the extremity rewarming procedures the rectal temperature lagged considerably behind the esophageal and aural canal (via indwelling thermocouple) temperatures. Thus large gradients may still exist between body compartments even though the heart is warmed.

Adult↗

Side-effects of oral misoprostol in the third stage of labour--a randomised placebo-controlled trial.

BACKGROUND: Misoprostol, an inexpensive, stable, orally active prostaglandin analogue, has been suggested for use in the prevention of postpartum haemorrhage. Potential side-effects, however, need to be quantified. OBJECTIVE: To compare the rate of postpartum shivering and pyrexia following oral misoprostol 600 micrograms and placebo. DESIGN: A double-blind placebo-controlled trial. Women in labour were randomly allocated to receive either misoprostol 600 micrograms orally or placebo after delivery. Conventional oxytocics were given immediately if blood loss was thought to be more than usual. Side-effects were recorded. Postpartum blood loss in the first hour was measured by collection in a special flat plastic bedpan. SETTING: The labour ward of an academic hospital in Johannesburg, with 7,000 deliveries per annum. MAIN OUTCOME MEASURES: Shivering and pyrexia. RESULTS: The groups were well matched. Misoprostol use was associated with more shivering (44% versus 11%, relative risk (RR) 4.03, 95% confidence interval (CI) 2.85-5.70), pyrexia > or = 37.8 degrees C (38% v. 6%, RR 6.23, CI 3.89-9.97), 1-hour systolic blood pressure > or = 140 mmHg (33% v. 25%, RR 1.32, CI 1.03-1.70), and diastolic blood pressure > or = 90 mmHg (10.5% v. 3.0%, RR 3.44, CI 1.67-7.11). There were no other significant differences. The study was not designed to be large enough to assess a difference in blood loss > or = 1,000 ml (9% v. 9.7%, RR 0.93, CI 0.56-1.53). Possible effects on blood loss may have been obscured by the lesser use of additional oxytocics in the misoprostol group (14% v. 18%, RR 0.78, CI 0.54-1.13). CONCLUSIONS: This study has shown the association of postpartum oral misoprostol 600 micrograms with shivering, pyrexia and hypertension. The increased blood pressure, as for the trend towards increased abdominal pain, may be secondary to the uterotonic effect of misoprostol. Large randomised trials are needed to assess the effectiveness of misoprostol in the prevention of postpartum haemorrhage, against which the disadvantages demonstrated here can be weighed.

Adult↗

Awake microlaparoscopy with the Insuflow device.

BACKGROUND AND OBJECTIVES: Patients undergoing laparoscopy often complain of shoulder pain, shivering, or both following laparoscopy. An increase in awake microlaparoscopic procedures has been reported. The objective of this study was to investigate the usefulness of heating and humidifying the carbon dioxide gas for the pneumoperitoneum with the Insuflow device (Lexion Medical, St. Paul, Minnesota) during awake microlaparoscopic procedures. METHODS: Awake microlaparoscopy was performed with the Insuflow device for heating and humidifying the carbon dioxide for the pneumoperitoneum. RESULTS: The incidence of transient shoulder pain in the Insuflow group was 5% compared with 40% in the dry carbon dioxide group. No patient in the Insuflow group complained of shivering, whereas 55% in the control group had shivering. Fogging of the microlaparoscope lens was decreased in the Insuflow group. CONCLUSIONS: Heating and humidifying the carbon dioxide gas produced fewer patient complaints of shoulder pain and shivering and decreased fogging of the microlaparoscope lens compared with procedures done with dry carbon dioxide during awake microlaparoscopic procedures.

Female↗

[The effect of intraoperative warming on patient core temperature].

OBJECTIVE: To investigate the influence of using fluid warming and forced-air warming system on patient core temperature, blood loss, blood transfusion, extubation time, and postoperative shivering. METHODS: Forty ASA (American Society of Anesthesiologists' Physical Status) I-II patients, aged 21-69 years, scheduled for elective abdominal surgery under general anesthesia, were enrolled in the study. The patients were premedicated with intramuscular dolantin 50 mg and atropine 0.5 mg. Anesthesia was induced with midazolam 1 mg, fentanyl 50-100 microg and propofol 1.5-2.0 mg/kg. Tracheal intubation was facilitated with vecuronium 1mg and succinylcholine 1.5-2.0 mg/kg. The patients were mechanically ventilated and anesthesia was maintained with isoflurane 1.5-2.0%, 50% N2O in oxygen and intermittent iv boluses of fentanyl (total dose 5-6 microg/kg). Vecuronium was used for muscle relaxation during maintenance of anesthesia. The patients were randomly divided into 2 groups: control group (n = 20) and warming group (n = 20). In both groups, the patients were covered with surgery blanket. In the warming group, patients were additionally warmed with fluid warming device and forced-air warming system during the operation. The core temperature was recorded every 20 minutes during the operation, as well as the blood loss, blood transfusion, extubation time and postoperative shivering. RESULTS: The core temperature at the end of the surgery was (36.4 +/- 0.4) degrees C in the warming group and (35.3 +/- 0.5) degrees C in the control group. The difference was statistically significant (t = 7.547, P < 0.001). There was no significant difference of blood loss and blood transfusion between two groups. The extubation time was significantly shorter in the warming group [(18 +/- 6) vs (26 +/- 10) min, t = -3.364, P = 0.002]. 6 patients shivered postoperatively in the control group and none in the warming group (chi2 = 7.059, P = 0.008). CONCLUSION: Fluid warming system and forced-air warming system can effectively maintain normothermia during the surgery and then help to reduce the extubation time and postoperative shivering.

Abdomen↗

The control of thermoregulation in the developing lamb during slow wave sleep.

This study investigates the mechanisms involved in adjusting metabolic rate in response to acute changes in ambient temperature close to thermoneutrality during postnatal development. Twelve lambs were prepared for sequential studies at 4, 14, 30, 45 and 55 days of age. During each study they were maintained at ambient temperatures of 5, 10, 15, 20, 25 and 30 degrees C for at least 1 h and until a slow wave sleep epoch was established. Eight lambs completed all studies. In these there was a significant fall in oxygen consumption with age which was independent of ambient temperature. This effect was closely related to a decrease in plasma triiodothyronine concentration that was greatest between 4- and 14-days old lambs and was not associated with a change in the plasma concentration of thyrotrophin or thyroxine. In 4-days old lambs oxygen consumption was increased at ambient temperatures of 5 and 10 degrees C by non-shivering thermogenesis, whilst in 14- and 30-days old lambs this effect was achieved by shivering. On the basis of significant changes in oxygen consumption and/or the occurrence of shivering (lower critical temperature) and panting (upper critical temperature) we have shown that there is a fall in both upper and lower critical temperature with age and a widening of the thermoneutral zone. This was associated with a decrease in the plasma cortisol concentration and heart rate as measured at thermoneutrality, whilst rectal temperature increased from 4 to 30 days of age. The other 4 lambs, 3 of which died between 7 and 17 days of age, had low plasma triiodothyronine concentrations when studied at 4 and/or 14 days of age and their oxygen consumption at thermoneutrality was significantly lower than the normal group at 14 days. Shivering thermogenesis occurred at an earlier age and control of body temperature was less effective. It is concluded that triiodothyronine has an important role in the control of metabolic rate in the developing lamb even to meet modest changes in ambient temperature, and possibly directly in survival.

Animals↗

Effects of carbon dioxide inhalation on physiological responses to cold.

Experiments were conducted to assess the thermoregulatory effects of CO2 breathing during cold exposures. Four men and two women (19-35 yrs old), clad in bathing suits, rested for 75 min on three occasions in a thermoneutral environment (29 degrees C) and on three occasions in the cold (5 degrees C). During these exposures the subjects breathed either: 1) air for 75 min, 2) air from 0-30 min, 4% CO2 in air from 30-60 min, and air from 60-75 min, or 3) 4% CO2 from 0-60 min and air from 60-75 min. Oxygen uptake (Vo2) was higher at 5 degrees C than at 29 degrees C due to shivering, but was not significantly effected by CO2 breathing. Rectal temperatures (Tre) were always higher in subjects exposed to 5 degrees C than 29 degrees C, declining with exposure time. Breathing 4% CO2 resulted in an acceleration in the decline of Tre in both environments. Neither Vo2 measurements nor accelerometer recordings of shivering supported previous reports of CO2-induced suppression of shivering. However, enhanced shivering may have occurred after cessation of CO2 breathing. Calculations of partitional heat exchange indicated that the greater decreases in Tre observed during CO2 exposures were due mainly to increased respiratory evaporative heat loss, total convective and conductive heat loss, probably all the result of hyperventilation.

Adult↗

Heated humidification in major abdominal surgery.

The influence of heated humidification on body temperature and postoperative shivering was studied in 30 patients undergoing major intra-abdominal surgery. In the control group (I) the anaesthetic gases, administered in a non-rebreathing system, were humidified by a sponge heat and moisture exchanger. In group II the gases were humidified and heated to 37 degrees C and in group III up to 40 degrees C. Anaesthesia, surface insulation and warming of the infusions were standardized. The temperature was registered at the lower oesophagus and the big toe. Shivering and the feeling of cold were estimated at 15 min intervals postoperatively. A good correlation was found between heat gain during the first hour of recovery, the feeling of cold and intensity of shivering. Intraoperative heat loss was minimal in all groups. Heated humidification had no statistically significant effect on the body temperatures or postoperative shivering and thus provided no additional advantage compared to the control group.

Adult↗

[Comparative characteristics of mechanisms regulating tubocurarine and cold tremor].

Tubocurarine tremor and shivering show identical topography in different muscle groups and identical frequency patterns of the EMG. Electrical stimulation of the medial preoptic area inhibits tubocurarine tremor and shivering. Reflexes from peripheral thermoreceptors are less important in regulating the tubocurarine tremor as compared with the shivering regulation. The data obtained show that tubocurarine tremor is a centrally induced analog of shivering.

Animals↗

Leg temperature and heat content in humans during immersion hypothermia and rewarming.

Core temperature afterdrop following cold water immersion has previously been shown to be greater during treadmill exercise than shivering (J. Appl. Physiol. 1987; 63:2375-9). To test the hypothesis that this results from increased transfer of heat from the core to exercising muscles, we quantified the changes in leg temperature and heat content during cooling and exercise/shivering protocols. Upper and lower leg muscle temperatures were measured at multiple depths in five thin healthy male subjects immersed in 8 degrees C water until core temperatures reached 32.8-34.9 degrees C. In these thin subjects there was a significant but small difference between exercise and shivering afterdrop (approximately 0.2 degrees C), and total leg heat content was unchanged during this period with both protocols. Subsequent heat gain was similar in both treatments but, in the lower leg, was greater during exercise than shivering, suggesting that shivering is less effective than exercise in increasing lower leg heat content.

Adult↗