c-peptide and Hypothermia

To investigate the effect of intraoperative amino acid infusion on blood glucose in patients under general anesthesia combined with epidural block.. 36 patients were randomly assigned to receive an intraoperative infusion of 18 compound amino acids (group AA) or lactated Ringer solution (group LR) at 2 ml·kg(-1)·h(-1). Nasopharyngeal temperature, and blood glucose, plasma insulin, C-peptide and glucagon concentrations were measured 30 min before induction (T0), 10 min after induction (T1), 30 min and 2 h after skin incision (T2, T3), and 30 min and 2 h postoperatively (T4, T5).. Nasopharyngeal temperature values, which decreased during surgery in both groups, were significantly higher in group AA than in group LR from T3 to T5. Compared with T0, the blood glucose concentration increased significantly from T2 in group AA and T3 in group LR to T5. Plasma insulin and C-peptide concentrations did not change significantly in group LR, while both increased significantly in group AA from T1 to T4. The plasma glucagon concentration did not change significantly in either group.. Intraoperative amino acid infusion in patients under general anesthesia combined with epidural block may accelerate the increase of blood glucose concentration and stimulate insulin secretion, and can alleviate hypothermia during the later period of surgery and postoperatively.

Topics: Adolescent; Adult; Amino Acids; Anesthesia, Epidural; Anesthesia, General; Blood Glucose; C-Peptide; Female; Glucagon; Humans; Hypothermia; Infusions, Intravenous; Insulin; Insulin Secretion; Isotonic Solutions; Male; Middle Aged; Ringer's Lactate; Young Adult

One of the biggest challenges of premature birth is acute hypoxia. Hypothermia during acute hypoxic periods may be beneficial. We hypothesized that prevention of hypothermia during neonatal hypoxia disrupts glucose homeostasis and places additional metabolic challenges on the neonate. Pups at PD2 and PD8 were exposed to 8% O2 for 3 h, during which they were allowed to either spontaneously cool or were kept isothermic. There was also a time control group that was subjected to normoxia and kept isothermic. Plasma glucose, insulin, C-peptide, corticosterone, and catecholamines were measured from samples collected at baseline, 1 h, 2 h, and 3 h. In postnatal day 2 (PD2) rats, hypoxia alone resulted in no change in plasma glucose by 1 h, an increase by 2 h, and a subsequent decrease below baseline values by 3 h. Hypoxia with isothermia in PD2 rats elicited a large increase in plasma insulin at 1 h. In PD8 rats, hypoxia with isothermia resulted in an initial increase in plasma glucose, but by 3 h, glucose had decreased significantly to below baseline levels. Hypoxia with and without isothermia elicited an increase in plasma corticosterone at both ages and an increase in plasma epinephrine in PD8 rats. We conclude that the insulin response to hypoxia in PD8 rats is associated with an increase in glucose similar to an adult; however, insulin responses to hypoxia in PD2 rats were driven by something other than glucose. Prevention of hypothermia during hypoxia further disrupts glucose homeostasis and increases metabolic challenges.

Topics: Animals; Animals, Newborn; Blood Glucose; Body Temperature; Body Temperature Regulation; C-Peptide; Catecholamines; Corticosterone; Female; Homeostasis; Hypothermia; Hypoxia; Insulin; Models, Animal; Pregnancy; Rats; Rats, Sprague-Dawley

Although "polar triiodothyronine (T(3)) syndrome" in chronic dwellers/workers in Antarctica has been established, alteration of the pituitary thyroid-axis upon accidental hypothermia is not well recognized. We report here a rare case of elevation of thyrotropin (TSH) upon accidental hypothermia.. A 75-year-old man was admitted because of consciousness disturbance.The mean outside temperature was approximately -2.0°C (28.4°F) but his house was inadequately heated. His rectal temperature was 29.5°C (85.1°F). Goiter was not palpable and pitting edema, not myxedema, was present. Serum TSH was elevated (28.3 mU/L, reference range 0.27-4.2), and free T(3) (FT(3)) and free thyroxine (FT(4)) lowered (FT(3), 3.25 pmol/L with a reference range of 4.00-7.85, and FT(4), 9.18 pmol/L with a reference range of 12.87-23.179), but thyroid-related autoantibodies were all negative. By the next morning, body temperature had risen to >36°C (>96.8°F) and there was no further recurrence of hypothermia. Serum TSH decreased exponentially and the patient's condition had become normal by day 22. FT(3) and FT(4) were found to be slightly lowered and elevated, respectively, during the same period, in the subnormal range. At the end of the observation period, the patient settled into the state known as "nonthyroidal illness syndrome.". Elevation of TSH in an elderly patient with accidental hypothermia was normalized after restoration of normal body temperature. Elevation of TSH upon accidental hypothermia was probably an adaptive response.. In patients with accidental hypothermia, the possibility of an adaptive elevation of TSH should be borne in mind. This clearly warrants further studies of the adaptation of the pituitary-thyroid axis in patients with accidental hypothermia.

Topics: Aged; C-Peptide; Humans; Hypothermia; Male; Thyrotropin

A 60-year-old woman presented to her primary care physician with fatigue and anemia. Laboratory evaluation revealed a hemoglobin level of 9.8 g/dL and an erythrocyte sedimentation rate (ESR) of 64 mm/hour. She subsequently developed nocturnal episodes of diaphoresis, confusion, and hypothermia. Capillary glucose measurements during the spells revealed hypoglycemia. During two supervised fasts, the patient's plasma glucose levels fell to 35 mg/dL and 32 mg/dL, respectively. Plasma insulin and C-peptide levels were appropriately suppressed, but a low concentration of beta-hydroxy-butyrate and normal increase of plasma glucose concentration after a glucagon injection suggested the presence of an insulin-like substance. Computed tomographic (CT) scan of the abdomen and subsequent positron emission tomographic (PET) scan revealed extensive lymphadenopathy. Biopsy of periaortic lymph nodes revealed Hodgkin's disease of the mixed cellularity type. Following chemotherapy, a complete remission ensued, the spells abated, and hypoglycemia was not induced by a 23-hour fast. We believe that the patient's Hodgkin's disease was producing an insulin-like substance. The observations of others suggest that this substance may be an autoantibody to the insulin receptor.

Topics: Antineoplastic Combined Chemotherapy Protocols; Autoantibodies; Bleomycin; C-Peptide; Dacarbazine; Doxorubicin; Female; Hodgkin Disease; Humans; Hypoglycemia; Hypothermia; Insulin; Middle Aged; Receptor, Insulin; Remission Induction; Vinblastine