Search PubMed⌕ Search

Biomedical subjects

I T Velasco

Publications and source records attributed to I T Velasco.

24 records · Page 2Linked to original sources
PubMed1981

Hyperosmotic NaCl and severe hemorrhagic shock: role of the innervated lung.

Infusions of hyperosmotic NaCl (2,400 mosmol/l; 4 ml/kg) were given to dogs in severe hemorrhagic hypotension by intravenous injection (72 expts) or intra-aortic injection (25 expts). In 46 experiments intravenous infusions were given during bilateral blockage of the cervical vagal trunks (local anesthesia or cooling). Intravenous infusions (without vagal blockade) restore arterial pressure, cardiac output, and acid-base equilibrium to normal and cause mesenteric flow to overshoot prehemorrhage levels by 50%. These effects are stable, and indefinite survival was observed in every case. Intra-aortic infusions of hyperosmotic NaCl produce only a transient recovery of arterial pressure and cardiac output but no long-term survival. Intravenous infusions with vagal blockage produce only a transient recovery of cardiac output, with non long-term survival. Measurement of pulmonary artery blood osmolarity during and after the infusions shows that a different pattern is observed in each of these three groups and strongly indicates that the first passage of hyperosmotic blood through the pulmonary circulation at a time when vagal conduction is unimpaired is essential for the production of the full hemodynamic-metabolic response, which is needed for indefinite survival.

Animals↗
PubMed1980

Treatment of refractory hypovolaemic shock by 7.5% sodium chloride injections.

Injections of hyperosmotic (7.5%) sodium chloride (100-400 ml) were given to 12 patients in terminal hypovolaemic shock who had not responded to vigorous volume replacement and corticosteroid and dopamine infusions. Hyperosmotic sodium chloride promptly reversed the shock in 11 of these patients. The immediate effects of the NaCl injections were a moderate rise in arterial pressure, the resumption of urine flow, and recovery of consciousness. These effects tended to persist for a few hours. The hyperosmotic infusion also reduced isosmotic fluid requirement by 90%.

Adult↗
PubMed1980

Hyperosmotic NaCl and severe hemorrhagic shock.

Intravenous infusions of highly concentrated NaCl (2,400 mosmol/l; infused volume 4 ml/kg; equivalent to 10% of shed blood), given to lightly anesthetized dogs in severe hemorrhagic shock, rapidly restore blood pressure and acid base equilibrium toward normality. No appreciable plasma volume expansion occurs for at least 12 h, indicating that fluid shift into the vascular bed plays no essential role in this response. Initial effects wee sustained indefinitely; long term survival was 100%, compared to 0% for a similar group of controls treated with saline. Hemodynamic analysis of the effects of hyperosmotic NaCl showed that these infusions substantially increase mean and pulse arterial pressure, cardiac output and mesenteric flow, whereas heart rate was slightly diminished. These effects immediately follow infusions with no tendency to dissipate with time (6-h observation). We conclude that hyperosmotic NaCl infusions increase the dynamic efficiency of the circulatory system, enabling it to adequately handle oxygen supply and metabolite clearance, despite a critical reduction of blood volume.

Animals↗
PubMedDate not supplied

Changes in body fluid and energy compartments during prolonged hunger strike.

UNLABELLED: Prolonged total food deprivation in non-obese adults is rare, and few studies have documented body composition changes in this setting. In a group of eight hunger strikers who refused alimentation for 43 days, water and energy compartments were estimated, aiming to assess the impact of progressive starvation. Measurements included body mass index (BMI), triceps skinfold (TSF), arm muscle circumference (AMC), and bioimpedance (BIA) determinations of water, fat, lean body mass (LBM), and total resistance. Indirect calorimetry was also performed in one occasion. The age of the group was 43.3+/-6.2 years (seven males, one female). Only water, intermittent vitamins and electrolytes were ingested, and average weight loss reached 17.9%. On the last two days of the fast (43rd-44th day) rapid intravenous fluid, electrolyte, and vitamin replenishment were provided before proceeding with realimentation. Body fat decreased approximately 60% (BIA and TSF), whereas BMI reduced only 18%. Initial fat was estimated by BIA as 52.2+/-5.4% of body weight, and even on the 43rd day it was still measured as 19.7+/-3.8% of weight. TSF findings were much lower and commensurate with other anthropometric results. Water was comparatively low with high total resistance, and these findings rapidly reversed upon the intravenous rapid hydration. At the end of the starvation period, BMI (21.5+/-2.6 kg/m2) and most anthropometric determinations were still acceptable, suggesting efficient energy and muscle conservation. CONCLUSIONS: 1) All compartments diminished during fasting, but body fat was by far the most affected; 2) Total water was low and total body resistance comparatively elevated, but these findings rapidly reversed upon rehydration; 3) Exaggerated fat percentage estimates from BIA tests and simultaneous increase in lean body mass estimates suggested that this method was inappropriate for assessing energy compartments in the studied population; 4) Patients were not morphologically malnourished after 43 days of fasting; however, the prognostic impact of other impairments was not considered in this analysis.

Adipose Tissue↗