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Biomedical subjects

J M Kinney

Publications and source records attributed to J M Kinney.

At least 109 records · Page 6Linked to original sources
PubMed1981

Nutrition for the patient with respiratory failure: glucose vs. fat.

High glucose intakes given during administration of total parenteral nutrition (TPN) have been demonstrated to increase CO2 production. The workload imposed by the high CO2 production may precipitate respiratory distress in patients with compromised pulmonary function. Changes in CO2 production and O2 consumption induced by TPN using either glucose as the entire source of non-protein calories, or fat emulsions as 50 per cent of the non-protein calories, have been analyzed either in patients with chronic nutritional depletion or in acutely ill patients secondary to injury and infection. In patients with chronic nutritional depletion, shifting from the lipid to the glucose system caused a 20 per cent (P less than 0.025) increase in CO2 production which resulted in a 26 per cent increase in minute ventilation (P less than 0.01). In the acutely ill patients receiving the glucose system, CO2 production was significantly higher than in those receiving the lipid system (179 vs. 147 ml.min-1.m-2; P less than 0.01. Fat emulsions can serve as a source of non-protein calories and are associated with lesser degrees of CO2 production than isocaloric amounts of glucose.

Adolescent↗
PubMed1981

Influence of injury and nutrition on muscle water electrolytes: effect of elective operation.

Injury is followed by a sequence of metabolic alterations which include fluid and sodium retention. This study used the percutaneous biopsy technique to analyze changes in muscle composition in regions nonadjacent to the area of surgical injury. The effect of nutritional intake on the changes observed in emphasized. Twenty-eight patients undergoing colectomy and 22 patients undergoing total hip replacement were studied. The patients undergoing colectomy resections received total parenteral nutrition with varying nitrogen intake. The patients undergoing hip replacement received either a) 5% dextrose solutions, b) 3.5% amino acid solutions, or c) both. Muscle biopsy procedures were performed preoperatively and postoperatively (day three on the colectomy patients) (day four on the hip replacement patients). The role of inactivity was assessed in eight healthy subjects maintained on strict bedrest for four days. Four subjects received a regular diet, while four received 5% dextrose solution for four days. The tissue samples were analyzed for water, sodium, chloride, potassium, magnesium, and in selected cases glycogen. No significant effects of bedrest with either a regular diet or semistarvation were observed. Surgical injury caused an increase in muscle water, sodium, and chloride while there was a slight reduction in potassium in all groups, with the exception of those colectomy patients who received no amino acids after operation. There was no effect of varying the level of nitrogen intake in the colectomy patients, nor was there an effect of different hypocaloric infusions, in the hip replacement patients. The colectomy patients on admission to the hospital, showed some signs of prior nutritional depletion. After receiving four days of preoperative nutrition, there was a decrease in extracellular water, in sodium and chloride towards normal values. Following injury, there was an increase in muscle water, sodium and chloride, while potassium decreased slightly. In the postoperative period there were only minimal effects of nutritional intake on the observed changes.

Bed Rest↗
PubMed1981

Influence of total parenteral nutrition on tissue lipoprotein lipase activity during chronic and acute illness.

This study examines the influence of total parenteral nutrition (TPN) compared with 5% dextrose (D5) infusion on skeletal muscle and adipose tissue lipoprotein lipase (LPL) activity in nutritionally depleted, injured and infected patients. The plasma concentrations of glucose, free fatty acid (FFA), triglyceride and insulin were also measured. During TPN, nutritionally depleted subjects showed an increase in adipose tissue LPL activity, "fat cell size," and plasma insulin concentration. Skeletal muscle LPL activity and plasma FFA concentration decreased. In comparison, trauma patients showed a less marked rise in adipose tissue LPL activity and skeletal muscle LPL activity increased. Infected patients had a much smaller rise in adipose tissue LPL activity than either of the other groups, and muscle activity rose. The depleted and injured patients showed a linear relationship between adipose tissue LPL activity and plasma insulin concentration and an inverse hyperbolic relationship between adipose tissue LPL activity and plasma FFA concentration.

Acute Disease↗
PubMed1981

Increasing glucose intake during total parenteral nutrition increases norepinephrine excretion in trauma and sepsis.

Total Parenteral Nutrition (TPN) was given to 15 traumatized or infected patients with all of the non-protein calories, either as intravenous glucose (Glucose System), or as 50% glucose + 50% intravenous fat (Lipid System). Before the administration of TPN, mean urinary excretion of unconjugated norepinephrine was 2.37 +/- 0.52 (SEM) microgram/kg/day, which is significantly higher than for normal subjects (0.62 +/- 0.04 microgram/kg/day; n = 56). TPN with the Glucose System for 4-6 days significantly increased the norepinephrine excretion from 1.95 +/- 0.47 to 6.77 +/- 0.95 microgram/kg/day (P less than 0.01). When TPN with the Lipid System was given the increase (from 3.05 +/- 0.89 to 4.26 +/- 0.70 microgram/kg/day) was not statistically significant. A modest increase in resting energy expenditure was seen with the Glucose System but not with the Lipid System. The administration of high glucose loads during TPN, in addition to providing nutritional support, may exert a metabolic stress as reflected by increased metabolic rate and increased catecholamine excretion. These metabolic changes are reduced when intravenous fat emulsions are substituted for a major part of glucose calories.

Adolescent↗
PubMed1981

Glycerol turnover and kinetics of exogenous fat in surgical patients.

In the United States, glucose has been until recently the sole non-protein energy substrate utilized in total parenteral nutrition (TPN). However, recent reports show that the administration of massive glucose loads to surgical patients cause a high incidence of pulmonary and hepatic complications. Indirect calorimetry data indicate that these hypermetabolic patients seem to utilize endogenous fat preferentially to carbohydrate. Therefore, we have undertaken some studies on the metabolism of endogenous and exogenous fat. Peripheral lipolysis - as estimated by measurements of glycerol turnover - is increased after injury and during sepsis. There is not correlation between the turnover of glycerol and the plasma concentration in surgical patients. High glucose intake induces a marked decrease in the glycerol turnover of nutritionally depleted subjects but has only a slight effect on the lipolytic rate of injured and septic patients. The rates of free fatty acid turnover and oxidation are elevated in surgical patients. High carbohydrate loads reduce FFA oxidation rate less in hypermetabolic patients than in depleted subjects. The utilization of exogenous fat was studied by associating an estimation of the oxidation rate to the measure of the clearance after the injection of 14C -Intralipid in surgical patients. Both oxidation and clearance rates are increased in these patients in relation with the severity of the injury. A dissociation between the variations of the clearance and the oxidation rates was observed when TPN was given to surgical patients. In such conditions, the clearance rate does not indicate the further utilization of a fat emulsion. Administration of TPN containing exogenous fat seem to induce less pulmonary and hepatic complications than TPN with glucose alone. In conclusion, kinetic measurements are needed for studying the metabolism of endogenous fat in surgical patients. An increased utilization of endogenous and exogenous fat takes place in these patients. Including exogenous fat as part of their parenteral diet is indicated but the optimal proportion of glucose and fat has not been precisely determined yet.

Adipose Tissue↗
PubMed1981

Lipoprotein lipase activity in surgical patients: influence of trauma and infection.

Hypertriglyceridemia commonly accompanies clinical sepsis and may be caused by increased hepatic production or decreased clearance of triglyceride from the bloodstream. In contrast, enhanced lipid clearing capacity is usually seen after uncomplicated trauma. The purpose of the study was to determine the role of lipoprotein lipase (LPL) in effecting the above changes. Enzyme activity was assayed in skeletal muscle and adipose tissue biopsy samples from 11 normal subjects and from 17 injured and 11 infected surgical patients. Normal subjects after 4 days of 5% dextrose infusion (D5) showed a significant decrease in adipose tissue LPL activity but no change in skeletal muscle activity. Trauma patients after several days of D5 had higher activity in adipose tissue and higher plasma insulin levels than diet-matched control subjects but showed no change in skeletal muscle activity. Infected patients with high plasma triglyceride levels had significantly decreased LPL activity in both tissues. A linear relationship was found between insulin concentration and adipose tissue LPL activity in normal subjects. We conclude that: (1) low tissue LPL activity in sepsis may result in diminished lipid clearance and contribute to hypertriglyceridemia, (2) after trauma, changes in tissue LPL activity as well as other factors such as altered hemodynamics play a role in determining in vivo lipid clearance, and (3) adipose tissue LPL activity is related to the plasma insulin concentration in normal subjects.

Adipose Tissue↗
PubMed1981

Metabolic and endocrine effects of fasting followed by infusion of five-percent glucose.

Isotonic glucose is often the sole nutrient provided to hospitalized patients with varying degrees of protein calorie malnutrition. To study the effects of such diets uncomplicated by illness, normal human subjects were fasted (6 to 14 days) before receiving an infusion of 5% dextrose (5 to 7 days). Norepinephrine excretion rose steadily-to six times control values-during the first 6 days of the fast and changed little thereafter. It remained high during the first 3 days of glucose infusion and subsequently returned toward normal. The rate of NTau-methylhistidine excretion changed little during the fast but decreased abruptly with glucose infusion. The magnitude of NTau-methylhistidine excretion indicated that undirectional muscle protein degradation was about equal to nitrogen excretion during the fast, and that the decrease in muscle protein degradation could account for the abrupt decrease in nitrogen excretion (from 91 to 30 mg N/kg . day) after glucose infusion. This suggests that the conservation of muscle protein caused by glucose infusion in this setting is affected by decreased degradation rather than by increased synthesis. Changes in NTau-methylhistidine excretion and total nitrogen excretion were more rapid than, and therefore not mediated by, changes in insulin concentration or norepinephrine excretion.

Adult↗
PubMed1981

Energy expenditure, nitrogen balance, and norepinephrine excretion after injury.

In this study we examine the effect of different hypocaloric nutritional regimens on nitrogen balance in patients following total hip replacement and compare it to that of normal subjects on strict bed rest. The interrelationship between nitrogen balance, energy expenditure, and urinary free norepinephrine excretion is analyzed with emphasis on the effects of nutrition on these relationships. Amino acid infusions following major elective orthopedic surgery had no nitrogen-sparing effect above that of 5% dextrose. Optimum nitrogen balance was obtained by administration of both 5% dextose and 3.5% amino acids. Patients receiving 5% dextrose showed no increase in resting energy expenditure in postoperative period compared to the preoperative control value. However, patients receiving amino acid infusions showed a 14% rise in energy expenditure postoperatively. Failure to administer 5% dextrose was associated with a high urinary norepinephrine excretion postoperatively. In normal subjects on bed rest either 5% dextrose or total starvation resulted in a marked fall in resting energy expenditure, whereas amino acid infusions isocaloric to the carbohydrate intake prevented any fall in resting energy expenditure. Nitrogen balance was improved with amino acid infusions in normal subjects. This study suggests the effect of amino acid infusions is highly dependent on the metabolic state of the patient.

Adult↗
PubMed1980

Respiratory changes induced by the large glucose loads of total parenteral nutrition.

Total parenteral nutrition (TPN) using glucose as nonprotein calories was associated with increases in O2 consumption (VO2) and CO2 production (VCO2). The magnitude of the changes was a function of the patient's clinical state and glucose load. Depleted patients showed a minimal increase in VO2, while VCO2 increased 23%. Minute ventilation (VE) increased 32%. Hypermetabolic patients (major trauma, sepsis) had a 30% increase in VO2 and a 57% increase in VCO2, while VE increased 71%. Patients with mild to moderate injuries (energy expenditure +/- 15% of normal) showed a 21% increase in VO2 and a 53% increase in VCO2, while VE increased 121%. Large carbohydrate intakes were associated with increases in CO2 production in all patients, while increases in O2 consumption were seen primarily in hypermetabolic patients. These changes suggest that the high glucose loads of TPN may be a physiologic stress.

Adult↗
PubMed1980

The effect of carbohydrate intake on the lipolytic rate in depleted patients.

The effect of intravenous carbohydrate intake on glycerol turnover and fat metabolism was estimated in six nutritionally depleted surgical patients requiring total parenteral nutrition. Two diets were given. Nitrogen intake was the same in both diets. The calorie intake, adjusted by varying glucose intake, provided either 72% or 128% of the measured resting energy expenditure. Glycerol turnover was measured during administration of 5% dextrose solutions before starting total parenteral nutrition, and again after 4 days on each diet. Turnover rates of glycerol were closely correlated with plasma concentrations. However, fractional turnover rates were only two-thirds of normal values, indicating decreased clearance possibly due to decreased hepatic blood flow. Glycerol turnover, plasma free fatty acid concentrations, and rate of fat oxidation declined progressively with increased glucose intake. When compared with these results, previous studies of injured and septic patients showed: higher values for glycerol turnover, FFA concentrations, and fat oxidation; poor corrlation between glycerol turnover and concentration; inhibition of lipogenesis at high glucose intake; and high rates of norepinephrine excretion. The data suggest that in severe injury, counter regulatory hormones may almost completely block the effects of insulin on hormone sensitive lipase but have less influence on insulin stimulation of FFA esterification and inhibition of ketone body synthesis.

Aged↗
PubMed1980

Some metabolic effects of fat infusions in depleted patients.

Severely depleted surgical patients were given total parenteral nutrition, providing an average of 34.6 kcal and 266 mg nitrogen/kg body weight. Two diets were used, one with glucose as sole source of nonprotein energy, the other with a fat emulsion, Liposyn 10%, substituted isocalorically for one-third of the glucose. The two diets were given alternately, for 1 wk at a time, to each patient. N balance, at zero energy balance, was estimated to average 50 mg nitrogen/kg, indicating that energy intake in excess of expenditure is not required to restore lean body mass in depleted patients. Nitrogen (N) balance was equally good with either diet. Respiratory quotients and carbohydrate oxidation were lower, and fat oxidation was higher with the fat-containing diet. Amino acids and glucose were infused continuously over each 24-hr period and fat was given for only 6--8 hr. During the period of fat infusion, fat oxidation was significantly higher, and carbohydrate oxidation and RQ were lower than at other times of day.

Aged↗
PubMed1980

Influence of total parenteral nutrition on fuel utilization in injury and sepsis.

Total parenteral nutrition with hypertonic glucose/AA solutions given to eighteen nutritionally depleted patients resulted in a rise in the respiratory quotient (RQ) from 0.83 to 1.05 (p less than .001), while oxygen consumption (VO2) increased only 3%. Excess glucose in depleted patients was converted to fat as evidenced by an RQ greater than 1.0. Administration of a similar glucose load to fourteen hypermetabolic patients (injury/infection) resulted in a rise in RQ from 0.76 to 0.90 while VO2 increased 29% (p less than .001) In hypermetabolic patients, even with administration of glucose in quantities above energy expenditure, there was still ongoing utilization of fat for energy, resulting in a RQ significantly less than 1.0. Excess glucose under these circumstances is apparently converted to glycogen while fat stores are utilized to partially meet energy needs. Septic and injuried man seems to preferentially utilize endogenous fat as an energy source. Administration of a large glucose load to hypermetabolic patients does not totally suppress the net fat oxidation as it does in depleted patients. Rather there is an increase in VO2, continuing oxidation of fat and apparently an increase in the conversion of glucose to glycogen.

Adult↗