Rectal Temp Research Articles

222 Effect of electronically controlled floor cooling pad on thermoregulatory performance of Duroc boars during the summer heat stress period

Abstract The objective of the study was to evaluate the effects of using electronically controlled floor cooling pad (ECP) to reduce physiological heat stress response during the summer season in a boar stud in Scottsville, Kentucky. Boars (n = 60; 526 ± 188 d of age) were placed in two rows of pens (2.06 x 0.66 m) of a 350 head tunnel ventilated boar barn and were randomly assigned to either CONTROL (n = 30; no ECP) or ECP treatments (n = 30). The ECP had 4.25 L cold water flushed through a group of 5 pads connected to each other, when temperature sensors reached 27°C or every 4 min for sensors placed on 5th pad and 24°C or every 4 min for sensors placed on 1st pad. Boars experienced a natural summer heat stress environment (daily temperature, humidity and dew point: mean = 24.03°C, 87.9%, 21.7°C, hourly mean high = 28.9°C, 83.4%, 25.8°C) for a period of 30 d from July 15, 2023 to August 14, 2023 wherein the cooling pad remained on and were flushing based on the set points mentioned above. Daily physiological measurements included respiration rate (RR), rectal temp (RT) and feed refusal (FR) collected during the hottest part of the day (1300 to1600 h) via counting chest or belly rises, using rectal thermometer and visual estimation, respectively. A mixed model in SAS (v.9.4) including the fixed effects of ECP, week, day, boar ID and their interactions with day in the week included as a random effect was used for the statistical analysis. Both RR and RT were decreased by ECP (P < 0.001), week (P = 0.027 and P = 0.005, respectively) and treatment by week interactions (P < 0.001). The overall RR and RT for boars on ECP (Mean = 15.2 breaths/minute, 38°C) were more stable compared with Control (Mean = 43.4 breaths/minute, 38.4°C). Increased RR (Mean = 55.7 breaths/min; daily high = 164 breaths/minute) and RT (Mean = 38.7°C; daily high = 40°C) were noted in wk 30 and 33 for CONTROL group while ECP group remained stable. The wk 30 and 33 RR and RT are caused by increased environmental temperatures and humidity (hourly mean high: temperature = 28.9°C, humidity = 84.9%, dewpoint = 21°C). FR increased as barn temperatures increased and treatment by week interactions were significant (P < 0.001), with a tendency for ECP to be overall less than CONTROL at P = 0.064. CONTROL boars had greater FR than ECP boars for wk 31 (P < 0.001), 32 (P = 0.001) and tendency for wk 33 (P = 0.098). These results indicate that the ECP effectively reduced the RR, RT and FR across the weeks with greater effects seen during the hottest weeks in the 30-d trial.

Early weaning and biological sex shape long-term immune and metabolic responses in pigs

During the early pre and postnatal life, host and environmental factors can impart a major influence on immune development, thus shaping lifelong disease resistance. Two major factors known to influence immune function and mortality in animals and people are early life stress and biological sex. How these two factors interact to shape long-term immune development and later life disease risk is poorly understood. Here we investigated how early weaning, a common early life stressor in pigs, and biological sex impacts long-term systemic inflammatory responses and hypothalamic–pituitary–adrenal axis (HPA axis) activation later in life. Ten-week-old female (F), intact-male (IM) and castrated-male (CM) pigs that were randomly assigned to early weaning (EW) and later weaning (LW) (at 15 or 28 days of age, respectively) were intramuscularly injected with either saline vehicle or lipopolysaccharide (LPS) to induce a systemic inflammatory response. Complete blood counts (CBC), proinflammatory cytokines, cortisol, testosterone, estradiol, and rectal temp were measured at 0 h, 2 h, and 4 h post-LPS challenge. At 4 h post-LPS, peritoneal fluid (PF) and white blood cells (WBC) were collected for differential analysis. LPS challenge significantly increased rectal temp and plasma cortisol level in all treatment groups. Together, the CBC results and immune cell counts in peritoneal cavity indicated that EW-F exhibited greater systemic immune response characterized by increased neutrophils to lymphocytes ratio (NLR) and enhanced neutrophil trafficking to the peritoneal cavity. Early weaning had an opposite effect on IM and CM pigs, which exhibited a suppressed LPS-induced neutrophil migration. Early weaning induced significantly greater cortisol responses only in IM pigs indicating a heightened HPA axis responses in EW-IM. how early weaning and biological sex affect immune and stress responses in pigs. Together, these results demonstrate that early weaning and biological sex and castration shape later life immune responses in pigs and provides insight into potential mechanisms driving sex differences in later life inflammatory disease risk and mortality.

Impact of Heat Stress on Physiological Characteristics, Blood Constituents and HSP Genes Expression in Mithun during Summer Season

Six healthy Mithun animals being reared in the shade and were not exposed to sunlight in the morning hours were termed as control group (T1). The same animals were exposed to sunlight from 6.00 am to 2.00 pm to induce heat stress and were termed as the heat stressed group (T2). The samples for observations on physiological, blood constituents and gene expression were recorded at 6.00 am (T1) and 2.00 pm (T2). The values for physiological characteristics, viz., rectal temp (100.04±0.26 vs 103.34±0.20), respiration rate per minute (26.67±0.52 vs 33.00±0.74) and pulse rate per minute (42.44±1.02 vs 59.83±0.84) were significantly (P<0.05) higher in the heat stressed group than non stress group. The values for blood constituents viz., glucose (50.82±1.27 vs 60.09±1.46), SGOT (44.91±0.89 vs 51.18±1.08), SGPT (44.17±0.87 vs 49.92±0.87), cortisol (712.48±0.03 vs 712.49±0.02) and THI (77.56±0.39 vs 81.42±3.40) were also significantly (p<0.05) higher in the heat stress group than non stress group. The values for expression of HSP 70 gene (28.24 ±0.15 vs 28.88±0.59) and HSP 90 gene (36.13±1.24 vs 35.87±1.90) were also significantly (p<0.05) higher in the heat stressed group of Mithun than non stress group. The results of the study revealed that summer heat stress had a significant effect in Mithun.

117 Update: Dantrolene Sodium Suspension (250 Mg/5mL) in Patients with Exertional Heat Stroke

Exertional heat stroke (EHS) is a rare, sudden and unpredictable hyperthermic, hypermetabolic crisis that may affect anyone performing intense physical activity. EHS is one of the most severe forms of heat illness and a leading cause of death and disability in athletes, outdoor workers and military personnel. EHS is marked by severe hyperthermia (core body temp. ≥40°C) and CNS dysfunction (eg, seizures, coma, abnormal behavior). The sporadic, unpredictable and life-threatening nature of EHS limits the ability to conduct prospective controlled clinical trials. Current treatment is limited to efficient body cooling which is infrequently available and inconsistently administered. Up to 1/3 of survivors may have long-term neurologic sequelae despite rapid body cooling. The objective was to evaluate the efficacy and safety of dantrolene sodium for injectable suspension (Ryanodex®) (DSS) for the treatment of EHS, administered as an adjunct to body cooling (BC). We conducted two comparable clinical studies evaluating DSS+BC compared to BC alone in patients with EHS. Study 1 (ITT N=34, mITT N=24) and Study 2 (ITT N=17) were randomized, controlled, 2-arm parallel studies. Patients had a core temp. ≥40°C, impaired level of consciousness (LOC)(GCS score <13) and tachycardia. The primary efficacy endpoint in both studies was the cumulative incidence of recovery of LOC defined as a GCS score ≥13 at or prior to 90 minutes post-randomization. Safety and tolerability were assessed. As reported at the 2017 ACEP Research Forum, the mITT population in Study 1 excluded patients who were intubated at baseline (precluding full assessment of GCS). Study 2 ran from August 2018 to August 2019. These multicenter studies were conducted in a real-world emergency medicine setting in the same hospitals. Due to the limitations enrolling EHS patients and given the comparability of the studies, an integrated analysis of efficacy was warranted. Study 1 and Study 2 demonstrated consistent, clinically meaningful results. Demographics and baseline characteristics in the integrated analysis were balanced between the DSS+BC (n=19) and BC only (n=22) groups regarding age (median 45 vs 43.5 yrs.), baseline GCS (mean 7.1 vs 6.2) and baseline rectal temp. (mean 41.6 vs 41.3°C). 51% were male. A statistically significant number of patients in the DSS+BC group met the primary endpoint vs BC alone (47.4% vs 18.2%, p=0.0452). Safety and tolerability findings were comparable in both groups and consistent with the known safety profile in the approved indication. Conducting clinical studies for EHS is challenging due to its rare, unpredictable and life-threatening nature. We conducted two comparable studies showing consistent and clinically meaningful benefit from the addition of DSS to BC. Approximately twice as many DSS treated subjects in each study achieved the primary endpoint. The integrated analysis of efficacy demonstrates that DSS added to BC results in a clinically meaningful and statistically significant improvement of neurologic impairment in subjects with EHS within 90 minutes of administration.

Dizziness - Runner

HISTORY: A 36 year old previously healthy male presented to the medical tent via wheelchair with acute onset of dizziness and nausea after finishing a marathon. He had met his goal of finishing just under 3 hours. He alternated water and sports drinks for fluid replacement. He described the dizziness as a spinning sensation that began shortly after crossing the finish line associated with emesis. This persisted while lying still with his eyes closed. Symptoms were exacerbated by tilting his head or attempting to look up. No lightheadedness, chest pain, shortness of breath, hearing changes, numbness or altered mental status. No history of vertigo episodes, recent illness or head trauma. In the medical tent, he vomited 3 times. He was laid supine with his legs elevated. Over 45 minutes, he had 5 cups of oral electrolyte replacement, 3 cups of water and a banana without improvement. He was eventually able to walk one lap around the medical tent while keeping his gaze focused downwards. PHYSICAL EXAMINATION: T 0 min: BP 120/58, HR 94, RR 19, O2 94% T 45 min: Supine BP 116/64, HR 63 Standing BP 105/60, HR 72 Rectal temp 97.9F He was mildly ill-appearing with clear mental status, alert and oriented x 4. Cranial nerves II-XII were intact and he demonstrated 5/5 strength in b/l upper and lower extremities. Extraocular movements and smooth pursuit were normal. No signs of spontaneous nystagmus. Nystagmus was observed with change in posture from sitting to supine to side lie. Head impulse testing was positive for compensatory saccade response. Dix-Hallpike maneuver to the right was positive for nystagmus and reproduction of symptoms. DIFFERENTIAL DIAGNOSIS: 1. Exercise associated postural hypotension 2. Exertional Heat Stroke 3. Exercise Associated Hyponatremia 4. Vestibular system dysfunction 5. Central nervous system lesion TESTS AND RESULTS: N/A FINAL/WORKING DIAGNOSIS: Benign paroxysmal positional vertigo (BPPV) TREATMENT AND OUTCOMES: 1. The Epley maneuver was performed, inducing one episode of emesis followed by gradual improvement of symptoms over the following 10 minutes. 2. Instructed to avoid rapid or frequent head movements for the next few days. 3. Gradual return to running after complete resolution of symptoms. 4. Follow up with primary care for any worsening of symptoms.

Abstract WP116: Early Hypothermia, But Not Delayed Hypothermia Ameliorates Ischemic Stroke Through Anti-inflammatory Process

Hypothermia is neuroprotective against many acute neurological insults. We and others have previously shown that protection by hypothermia is associated with the suppression of the inflammatory response that accompanies stroke. However, comparative mechanisms of the anti-inflammatory process through different hypothermic paradigms have surprisingly not been studied. In this study, we treated mice to early (protective) and delayed (not protective) hypothermia in a stroke model and compared the effect of cooling on the inflammatory response. We also explored the influence of a novel protein, triggering receptor expressed on myeloid cells-2 (TREM2), which is thought to be an important receptor involved in the innate immune response. TREM2 has previously been shown to promote phagocytosis of apoptotic neurons. We subjected male C57/BL6 mice to permanent middle cerebral artery occlusion (MCAO). We identified 2 cooling paradigms, one where cooling (rectal temp=30C) began at the onset of MCAO (early) and a second where cooling began 1h later (delayed). In both cases, cooling was maintained for 2h. A 3rd group was maintained at normothermia as a control (36C). Mice were survived 1, 3, 7, 14 &amp; 30d (n=6/group/time point). Mice from the normothermic and delayed cooling groups had similar ischemic lesions sizes and neurological performance, but mice cooled early showed marked protection as evidenced by smaller lesion size and few neurological deficits at all time points (p &lt; 0.05, 40% reduction). Microglia/macrophages and TREM2 were decreased only in the early cooling group (P &lt; 0.05). Immune cells were reduced only where hypothermia was protective and we conclude that inflammation is probably related to the amount of injury present, and not whether cooling occurred.

A Pressing Headache

A Pressing Headache

BODY COOLING BETWEEN EXERCISE SESSIONS IN THE HEAT DECREASES THIRST IN THE ABSENCE OF REHYDRATION

PURPOSE We assessed if body cooling between exercise sessions in the heat would alter thirst responses in the absence of rehydration. This is relevant given the recent increase in pro-active body cooling procedures. METHODS 15 heat-acclimated highly-trained runners (age - 28 ± 2yrs, body fat-11.9 ±1.3% wt −68.9 ± 2.3kg, ht-180 ± 2cm, training volume-87 ± 11km/wk) completed a hilly trail run (approx. 19 km and 86 min) in the heat (WBGT =27°C) at an individually selected “comfortable” pace on 3 (1-wk apart) occasions. The trials (random, cross-over design) included: 1) Distance Run (DR) then 12 min of ice-water (5.23 ± 21°C) immersion (IWI) then a 3.2 km race in the heat; 2) DR then 12 min of cold-water (13.98 ± .31°C) immersion (CWI) then a 3.2 km race in the heat; 3) DR then 12 min of mock (no water, air temp = 29.50 ± 72°C) immersion (MI) then a 3.2 km race in the heat. Immersion included submerging torso and upper legs. 15 min elapsed after immersion and start of race. No rehydration occurred during any trial. Thirst was reported using a 9-point scale with verbal anchors ranging from 1 (not thirsty) to 9 (very thirsty) at pre-DR, pre-immersion (PRI), post-immersion (POI), and post-race (PR). RESULTS Length of DR, time to complete DR, rectal temp (39.45 ± .18°C) and % dehydration (−3.73 ± .22%) following DR, and WBGT were similar (p >.05) among all trials. IWI rectal temp was less (p <.05) than MI POI and CWI and MI PR. CWI rectal temp was less (p <.05) than MI POI and PR. Thirst sensation was greater (p <.05) for MI (7.3 ± .3) than IWI (6.5 ± .4) and CWI (6.3 ± .5) POI. Thirst was similar (p >.05) pre-DR, PRI, and PR for IWI (2.9 ± .2, 7.1 ± .3, 7.6 ± .3), CWI (2.9 ± .3, 7.5 ± .4, 7.8 ± .4), and MI (2.2 ± .2, 7.6 ± .4, 8.2 ± .3), respectively. CONCLUSION Body cooling decreases sensation of thirst. These findings should encourage athletic trainers to reinforce hydration practices during and following body cooling due to decreased perception of thirst.

Effect of acute stress on circulatory levels of adrenocorticotropic hormone in rats locally head-irradiated with X-rays

In order to study the effects of ionizing radiation on the pituitary gland before and after an acute stress attack, rats aged 8 days were locally head-irradiated with a single dose of 9.6 Gy of X-rays. One group of animals was irradiated under hypothermia (rectal temp. 5.96 ?C). At the age of 46 days, the animals were sacrificed and circulatory adrenocorticotropic hormone levels were measured by the RIA method. Basal ACTH levels were lower in the irradiated animals when compared to the non-irradiated controls (p&lt;0.05). After an acute stress attack, the irradiated animals showed significantly lower ACTH levels compared to the non-irradiated controls (p&lt;0.001). Animals subjected to hypothermia during irradiation, after an acute stress attack, showed significantly higher ACTH levels in comparison to animals irradiated under normal body temperature (p&lt;0.001). It may be concluded that a dose of 9.6 Gy of X-rays reduces the post-stress response of the pituitary gland and that hypothermia effectively protects the pituitary gland when ionizing radiation is concerned.

A Cardiopulmonary Bypass Perfusion Technique for the Surgical Repair of Aortic Type I Dissections Requiring the Elephant Trunk Procedure

The effect of cerebral and spinal cord protection by a modified perfusion technique during the elephant trunk procedure was assessed. Between 1997 and 1998, six patients underwent selective cerebral perfusion (SCP) and lower half of the body perfusion (LBP), in which the right subclavian and left femoral arteries were separately cannulated and perfused by individual pump heads. Moderate systemic cooling was used (nasal temp. 20–30°C; rectal temp. 23–26°C). The open distal aortic repair was performed using only the selective cerebral perfusion; while the aortic arch reconstruction was performed using both selective cerebral and lower half of the body simultaneous perfusion. Blood oxygen saturation of the left jugular vein (SjO2) and regional oxygen saturation cerebral (rSO2) in the front region of the brain, was monitored along with the pressure of the left temporal superficial and femoral artery. The mean cardiopulmonary bypass time was 136 minutes, with a mean arrest time of 92 minutes. Mean duration of isolated selective cerebral perfusion was 23 minutes, with flow rates of 5–8 mL/kg/min; a left temporal superficial artery pressure of 50 mmHg; SjO2 65–80%, and rSO2 58–72%. Mean duration of simultaneous selective cerebral and lower half of the body perfusion was 27 minutes; cerebral flow rates 5–8 mL/kg/min; the left temporal superficial artery pressure of 45–50 mmHg; SjO2 70–85% and rSO2 55–76%. At the same time, lower half of the body flow rates were maintained within 30–50 mL/kg/min; with a femoral artery pressure 50–80 mmHg. Mean extubation time was 28 hours; mean ICU time was 4.5 days. There were no neurologic complications in any patient. All patients survived the operation and were discharged from the hospital. This modified perfusion technique of SCP and LBP worked well and provided satisfactory cerebral and spinal cord protection.

Assessing and Managing the Febrile Child

A fever is defined as a rectal temp over 100.4 degrees F. Fever occurs when the hypothalamic thermoregulation center resets the temperature set point in response to a chain of events initiated by the inflammatory response. Glass thermometers remain the gold standard and electronic thermometers are generally acceptable, but studies do not consistently support the use of infrared ear thermometers in children under 3. Evaluation of the sick child includes observation, assessment of age and temperature risk factors, history and physical, and lab tests. To aid in the assessment of how ill or "toxic" a child appears, the Yale Observation Scale is used. Acetaminophen remains the antipyretic of choice. Febrile seizures are generally benign. Tepid sponge baths are only slightly more effective than acetaminophen alone in reducing fevers, but may be useful for children with a history of febrile seizures or liver disease. While there are many causes of pediatric fevers, they can be grouped into three general categories: fever with localizing signs, fever without localizing signs, and fever of unknown origin. Children with a localized infection are treated with antibiotics, antipyretics, and parent education; children with fever of unknown origin are referred for more in-depth evaluation. The management of children presenting with fever without a source is discussed in detail.

Axillary Safer than Rectal Temp?

Axillary Safer than Rectal Temp?

1354 THE RELATIVE EFFICACY OF AN INCUBATOR AND AN OPEN WARMER IN PRODUCING THERMONEUTRALITY IN SMALL PREMATURES

Other studies comparing oxygen consumption (VO2) in open radiant warmers (RW) and convectively heated incubators (I) demonstrated a trend toward lower VO2 in the I. This study using a larger group of babies documents that the trend represents a significant difference and an RW is less able than an I to produce a neutral thermal environment for premature infants. The VO2 of 16 babies less than 1500 gm were measured in I and under RW. Both warming systems (WS) were set to maintain skin temp near 36° (skin temp I 36.04±.03 SE, RW 35.99±.01 SE, p= NS). The skin temp probe was shielded from IR radiation. Babies had a mean weight of 1340 gm (1000-1490 gm), mean age of 22 d (6-49 d) and mean post conceptional age of 34 wks (29-40 wks) when studied. VO2 was measured during a period of non-rem sleep on each baby after at least an hour in each of the two WS-order randomized. There were no significant differences in rectal temp (I=36.9±.1°, RW=36.9±.1°), face temp, mean skin temp (weighted average of 9 skin temps), or time since fed. Air temp (I=33.4±.4, RW=27.9±.3, p<.001), foot temp (I=35.2±.2, RW=33.6±.4, p<.001) and humidity (I=75±2, RW= 55±2, p<.001) were lower in the RW. Mean VO2 (ml/kg/min ± SE) was 6.84±.37 for the I and 7.45±.44 for the RW (p<.02 by two tailed t test). The radiant warmer was less able to induce a minimal metabolic rate than the incubator. Thus if thermoneutrality is required in small premature infants, open radiant warmers should not be used.

1253A THE PATTERN OF BREATHING OF KITTENS DURING HYPOXIA

The reduction in (F,I,O2) in preterm infants and in anaesthetized kittens less than 35 days of age produces an increase in ventilation which is not sustained. This has been widely interpreted as respiratory failure. We studied the pattern of breathing during hypoxia in 16, pentobarbitone anaesthetized kittens 5-30 days of age, and have related it to oesophageal pressure, diaphragm (Dia) e.m.g., phrenic activity (PA) carotid chemoreceptor discharge, arterial pressure, expired FCO2 and FO2 PaCO2, PaO2, PHa and rectal temp. F1O2 was reduced from 0.21 to 0.06- 0.12, sometimes adding CO2. Respiratory frequency (f) and tidal volume (VT) was increased within 30 sec. Over 5 min f fell to up to 60% below control and arterial pressure fell in 22 of 43 trials in 9 kittens , sometimes preceding the fall in f. Even when f and VT fell CO2 was always below control. Adding CO2 did not prevent this fall. Hypoxia did not change the relationship between VT and oesophageal pressure or Dia. The ratio of high to low frequencies in the Dia. did not change. PA did not always correlate well with DIA,but this was not altered by hypoxia. Carotid chemoreceptor discharge increased within 15 sec of lowering FI,O2 and at 5 min. it was still much above control. Since the decrease in ventilation was not accompanied by hypercapnia nor muscle fatigue it is not respiratory ‘failure’. A specific central effect modulating breathing pattern must be considered. The Wellcome Trust (Grant 9594/1.5).

993 ISOLATED PULMONARY HYPERTENSION FOLLOWT SEVERE POSTNATAL SHOCK

Four term neonates 3-14 days old had isolated pulmonary hypertension (PH) 2-10 days following postnatal hypotensive shock (BP< 25 mmHg flush, pH-6.94-7.17, Base deficit=17-26 mEq/L, and consumption coagulopathy). Shock was due to coarctation in 2 infants, E. coli sepsis in one, and severe cold stress (rectal temp.=94°F) in one. Unlike infants with persistence of fetal circulation (PFC), pre- and perinatal histories were normal: Apgars = 8-10, Birth Weight = 3.2-4.2 kg. No infant was cyanotic (pO2>110 in O2); none had symptoms in the first 2 days of life. After resuscitation and successful medical and/or surgical therapy of the underlying disorder, each infant developed heart failure (CHF), right ventricular hypertrophy (RVH), and X-ray signs of pulmonary edema. Catheterization 2-10 days after the shock revealed PH at or above systemic levels (systolic pressure = 60-100 mmHg), but no anatomic heart disease. CHF requiring digitalis persisted for 6-12 months: RVH persisted for 1-3½ years. All 4 children were asymptomatic by 2 yrs. with normal intracardiac pressures at followup catheterization (1-2½ yrs.). The findings in these infants differ from those reported with PFC or 1° PH, and support the hypothesis that severe shock, with but hypoxemia, may result in prolonged but reversible PH. The direct cause may be related to acidemia, tissue hypoxia, micro-emboli, or hypotension itself. The findings also suggest a possible contribution of shock in the genesis of other neonatal forms of PH.

1038 REDUCTION OF INSENSIBLE WATER LOSS (IWL) IN PREMATURES UNDER RADIANT WARMERS

Excessive IWL is a well known complication in prematures placed under radiant warmers. A controlled study was therefore undertaken to determine if a plastic dome would be useful in minimizing IWL. Twenty-nine AGA healthy infants with gest. age of 30.9±0.4 wks (mean±S.E.) birth wt. 1.4±.03kg and postnatal age of 8.7±2.1 days were studied. IWL was determined from insensible wt. loss measured on a Potter Bed Balance scale. Water losses from urine and stool were prevented by attaching a plastic pouch to the perineum. IWL was measured under 2 conditions in the same infant: with heat shield (Grp A) and without heat shield (Grp B). Each study period extended for 3 hrs after 30 min. of stabilization. The studies were done in an infra-red radiant warmer (Ohio) with servo-control set at skin temp. of 36.5°C. Skin, rectal, ambient temp. RR, HR and wt. loss were monitored and recorded every 30 min. Total IWL was significantly lower (p<.01) in Grp A as compared with Grp B infants (1.76±.24 vs 2.74±.3 g/kg/hr). RR, HR and skin temp. were similar in both groups. Ambient temp. was higher (p< .01) in Grp A, 34.6±.25°C. than in Grp B, 30.6±.26°C.; rectal temp. was lower (p<.01) in Grp A, 36.7±.13°C. than in Grp B, 37.2±.l°C. The lower IWL of Grp A infants may be due to a smaller skin-air ambient temp. gradient in Grp A than in Grp B. The shield may also alter air flow pattern, resulting in an insulating layer of saturated air over the baby which reduces evaporation from the skin.

FAILURE OF PRETREATMENT WITH WR-2721 TO PROTECT RABBIT LUNG FROM IRRADIATIATION DAMAGE

Radioprotective drugs such as S-2 [3-Aminopropylamino] Ethylphosphorothioic acid (WR-2721) have been suggested for use to prevent radiation pneumonitis complicating radiotherapy of primary and metastatic tumors of lung, mediastinum, and chest wall. Juvenile female New Zealand White rabbits (R) between 9 and 12 months of age were either given saline or WR-2721 (36.5 mg/Kg) intravenously 15 minutes before irradiation. Low dose R (n=7) received 250 rads × 4 days to the thorax while high dose R (n=7) were given 375 rads × 4 days. Two, four and six weeks after initiating irradiation, animals were killed and pulmonary pressure volume studies performed. No significant differences between treated or control R (n=7) were seen in body weight change, food intake, water consumption, respirations, PaCO2, WBC, Hct, rectal temp, lung weight, lung distensibility, lung compliance, minimal surface tension or histologic changes. Pretreatment with WR-2721 does not seem to protect juvenile rabbit lung from irradiation damage.

The effects of intermittent warm-up on 7-9 year-old boys.

Twelve boys, 7-9 years old, who, by use of questionnaires, were found to be ignorant of the concept of "warm-up", performed maximal aerobic and anaerobic tasks 4 min after completing a 15 min intermittent warm-up (WU) (30 sec treadmill run, 30 sec pause). The WU required some 60% of the individual's VO2max, and raised rectal temp. by 0.52 +/- 0.19 degrees C. The aerobic criterion task (CT) was a one-stage bicycle ride at a load predetermined to exhaust the subject after 4 min. The anaerobic CT was a 30 sec all-out ride against resistance of 35 gm/kg BW. Subjects also performed both CT's without any WU. VO2max (aerobic CT), HRmax, as well as total mechanical work output achieved during the aerobic CT, were significantly higher with WU, compared with the non-WU sessions. During the anaerobic CT total revolutions, total power output, as well as peak HR, were significantly higher following WU. It is suggested that the benefits of intermittent WU, as used in this study in young children, can be attributed to physiological rather than psychological mechanisms.

Effect of panax ginseng root on exhaustive exercise in mice

Effects of extracts obtained from Panax Ginseng root on recovery from exhaustion, were studied using six methods: exploratory movement (EM), hole cross (HC), rotating rod (RR), sliding angle (SA), spring balance (SB) and rectal temp. (RT) tests. Four hr oscillation movements were used as enforced exercise. Drugs were injected i.p. immediately following the exercise. Water extract significantly accelerated the recovery of exploratory movements, increased motor activity index in EM test and elevated rectal temp. However, water extract decreased the index in HC test and grip tone in SB test. Anti-fatigue effects of Ginsenoside Rgl were obvious in every test. Lipophilic fraction significantly speeded up recovery from fatigue in EM, RR, RT and SB tests, but delayed recovery in HC and SA tests. Neutral saponins fraction had no effect on recovery in the 6 tests. In the EM tests, devised to measure two kinds of exploratory movements of fatigued mice and their spontaneous movement, methamphetamine (2 mg/kg), caffeine (25 and 50 mg/kg), 2-dimethylaminoethanol (25 mg/kg) and glucose (100 and 200 mg/kg) significantly speeded up the recovery of these two exploratory movements, and increased the spontaneous movement.

Effect of Panax Ginseng root on exhaustive exercise in mice.

Effects of extracts obtained from Panax Ginseng root on recovery frorr exhaustion, were studied using six methods: exploratory movement (EM), hole cross (HC), rotating rod (RR), sliding angle (SA), spring balance (SB) and rectal temp. (RT) tests. Four hr oscillation movements were used as enforced exercise. Drugs were injected i.p. immediately following the exercise. Water extract significantly accelerated the recovery of exploratory movements, increased motor activity index in EM test and elevated rectal temp. However, water extract decreased the index in HC test and grip tone in SB test. Anti-fatigue effects of Ginsenoside RgI were obvious in every test. Lipophilic fraction significantly speeded up recovery from fatigue in EM, RR, RT and SB tests, but delayed recovery in HC and SA tests. Neutral saponins fraction had no effect on recovery in the 6 tests. In the EM tests, devised to measure two kinds of exploratory movements of fatigued mice and their spontaneous movement, methamphetamine (2 mg/kg), caffeine (25 and 50 mg/kg), 2-dimethylaminocthanol (25 mg/kg) and glucose (100 and 200 mg/kg) significantly speeded up the recovery of these two exploratory movements, and increased the spontaneous movement.