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C Chiarla

Publications and source records attributed to C Chiarla.

36 records · Page 2Linked to original sources

Relationship of plasma cholesterol level to doses of branch-chain amino acids in sepsis.

Plasma cholesterol levels, plasma lactate, and total body RQ were measured in septic patients undergoing total parenteral nutrition (TPN) with glucose, fat, and two different branch-chain amino acid admixtures (49% BCAA and 16% BCAA). Mean plasma cholesterol for all measurements (2.61 +/- 0.94 [SD] mmol/L) was lower than normal; however, it was higher with 49% BCAA than with 16% BCAA (2.94 +/- 0.95 vs. 2.27 +/- 0.81 mmol/L, p less than .001) for comparable loads of glucose, fat, and total amino acids. Plasma lactate and RQ were lower with 49% BCAA than with 16% BCAA (p less than .001 for both). Cholesterol was directly related to the absolute dose of BCAA (p less than .001), was unrelated to the dose of non-BCAA, and was inversely related to lactate (p less than .001). These results suggest that BCAA ketoacids contribute to cholesterol synthesis in sepsis, as well as being an oxidative source. The data also suggest that the reduction in alanine in BCAA-enriched amino-acid TPN assists in the lowering of plasma lactate secondary to abnormal septic glucose metabolism.

Adult↗

Respiratory index/pulmonary shunt relationship: quantification of severity and prognosis in the post-traumatic adult respiratory distress syndrome.

The relationship between the respiratory index (RI = alveolar-arterial oxygen gradient [P(A-a)O2] normalized by PaO2) and the pulmonary shunt (Qsp/Qt) has been examined in 929 studies from 240 critically ill post-traumatic patients. Of these, 88 patients (443 studies) were individuals who developed post-traumatic adult respiratory distress syndrome (ARDS) and 152 were patients (486 studies) who did not develop ARDS. This study demonstrates that the RI to Qsp/Qt [RI/(Qsp/Qt)] relationship was significantly (p less than .0001) increased in patients who developed fatal ARDS compared with those who did not develop ARDS, or with those whose ARDS resolved. Because of the increased oxygen consumption (VO2) in ARDS patients in association with their severe limitations in gas exchange (RI) and increased Qsp/Qt, surviving ARDS patients had a significant increase in the cardiac index which resulted in a higher oxygen delivery to VO2 ratio. ARDS patients showed significant (p less than .0001) evidence of increased pulmonary vascular tone, correlated with the increase in the RI/(Qsp/Qt) relationship. In addition, those patients with high RI/(Qsp/Qt) also had increased right ventricular (RVSW) to left ventricular work (LVSW) ratios which were shown to be a direct function of the rise in RI. This increase in both RVSW/LVSW and RI/(Qsp/Qt) ratios was significantly (p less than .0001) correlated with an increased mortality. Thus, the RI/(Qsp/Qt) relationship, which can be obtained from arterial and mixed venous blood gases and saturations only, can be used to predict the severity of the ARDS process as well as important pulmonary vascular and right ventricular overload consequences.

Hemodynamics↗

Calorimetric response to amino acid infusion in sepsis and critical illness.

The effect of the infusion of mixed amino acids with glucose and fat on metabolic rate (MR) in sepsis (S) and in nonseptic trauma (NS) was investigated. The results demonstrated that diet-induced thermogenesis (specific dynamic action) controlled in S and in NS 25% and 18% of the MR variability, respectively (r2 = .25 and .18, p less than .01 for both). Also, diet-induced thermogenesis represented a quantitatively relevant portion of the total MR. There was a larger thermogenic effect of amino acids in S with respect to NS (22.3 vs. 5.7 cal/mg N, p less than .01) with a concomitantly increased thermogenic effect of fat. The results suggest the importance of recognizing the thermogenic effect of administered nutrients as an important determinant of MR during calorimetric measurements. The finding of an enhanced thermogenic effect of amino acids and fat in S also implies the need for more complete investigations of the impact of these substrates in modifying oxidative and energy metabolism in S.

Adult↗

Inhibition of post-traumatic septic proteolysis and ureagenesis and stimulation of hepatic acute-phase protein production by branched-chain amino acid TPN.

Previous studies have shown that severe sepsis after major trauma results in the reprioritization of release of hepatic acute-phase proteins (APP). They suggest competition for leucine for nutritional utilization may be responsible. To test this hypothesis, a branched-chain enriched (46.6%) amino acid mixture (BCAA) was administered on a prospective randomized basis with standard TPN therapy to 16 septic post-trauma patients. After sepsis was diagnosed, a randomized therapy (control-TPN or BCAA-TPN) was given for 12 days, or until death occurred. Total calories and amino acid nitrogen (N) administered were not different in the two groups (t-test) and q 8 h (347 study periods) amino acid clearances, urinary urea nitrogen excretion, muscle proteolysis from 3-methyl-histidine (3-MH) excretion, and standard indices of sepsis severity and hepatic function were measured, as well as platelets (PLAT), leucocytes (WBC), albumin (ALB), and six acute-phase proteins: C-reactive protein (CRP), alpha-1-antitrypsin (A1TRIP), fibrinogen (FIBRIN), alpha-2-macroglobulin (AMACRO), ceruloplasmin (CERUL), and transferrin (TRANS). Using Scheffé analysis of all contrasts the data showed: BCAA resulted in a fall in 24-hour urea N excretion (24.0 to 20.0 gm/24 hr) and in proteolysis (138 to 126 gm/24 hr) (p less than 0.0001). Prestudy CRP levels were all elevated, but compared to control where APP reprioritization occurred, over the initial 10 days of therapy BCAA patients had a more rapid fall in CRP with a more rapid rise in FIBRIN, TRANS, CERUL, ALBUMIN, AMACRO, and A1TRIP (all p less than 0.0001) relative to CRP. Also, the sepsis-reduced clearances of glutamine and glutamate, alanine, and proline were increased (p less than 0.0001) during BCAA even though urea nitrogen production was reduced (p less than 0.0001). The increase in leucine clearance with BCAA-enriched TPN was positively correlated (r2 = 0.601; p less than 0.0001) with the increase in the sum of all APP and ALB and was also associated with an increase both in FIBRIN and in platelets (p less than 0.0001). The BCAA-related increase in FIBRIN (9.1 to 11.9 mg/ml) occurred at the same time as a fall in prothrombin time (p less than 0.0001). BCAA-enriched TPN reduced proteolysis and amino acid catabolism and appeared to increase the levels of the more rapidly appearing anti-inflammatory and nutritional hepatic APP and formed coagulation elements in post-traumatic sepsis.

Acute-Phase Proteins↗

A simple method for rapid estimate of pulmonary venous admixture.

Data from 2,298 measurements of pulmonary venous admixture (QS/QT) performed in 733 patients were analyzed and processed in order to develop a method for rapid and reliable estimation of QS/QT by a simplified approach. Formulae and charts were obtained, which are easily suitable for use in all settings, and permit estimation of QS/QT with an 85%-93% control of its variability (r2 = 0.85-0.93, p less than 0.0001) simply on the basis of the measured arterial and central venous O2 tensions or saturations.

Adolescent↗

Prediction of arterial blood gases by transcutaneous O2 and CO2 in critically ill hyperdynamic trauma patients.

The management of severe adult respiratory distress syndrome in critically injured patients requires the frequent measurement of arterial blood gases for adjustment of cardiovascular and ventilatory support. Since these require blood withdrawal and laboratory determinations, a noninvasive method of assessment of arterial gas tensions would permit more frequent assessment of the patient as well as permitting rapid changes in the patient's ventilatory status to be detected earlier in the clinical course. The role of transcutaneous O2 and CO2 tension in providing these measurements was evaluated in 92 studies in 38 critically ill patients with ARDS due to trauma and/or sepsis. All patients were normodynamic or hyperdynamic at the time of study (cardiac index 2.5 to 7.6 L/min/m2) and were intubated and on increased inspired oxygen fractions (FIO2 = 30 to 100%) delivered by mechanical ventilation, had a range of body temperature from 35.0 to 39.5 degrees C and pH from 7.29 to 7.57 The data from a transcutaneous O2 and CO2 sensor applied to the skin of the anterior thorax were analyzed by multiple regression analysis of variances. Prediction of the arterial oxygen tension (PaO2) from 52 to 253 torr was possible from regression-corrected measurements of the transcutaneous O2 (TcO2): [PaO2 = 1.1 (TcO2) - 0.28 (FIO2) + 45.5]. The arterial carbon dioxide tension (PaCO2) from 26 to 57 torr was predicted from the transcutaneous CO2 (TcCO2):[PaCO2 = 0.76 (TcCO2) + 0.06 (FIO2) + 0.035 (TcO2) + 4.1]. With these corrections, a noninvasive Respiratory Index was computed for assessing ARDS severity, and dynamic changes in arterial gases could be followed in response to postural changes, ventilatory alterations, or cardiovascular perturbations. These data suggest that a reasonable estimate of the arterial blood gases can be obtained from a regression-corrected measurement of the transcutaneous O2 and CO2 tensions in critically injured normodynamic or hyperdynamic ARDS patients.

Adult↗

Cardiorespiratory and metabolic effects of buflomedil: case reports.

An extensive study has been performed of the cardiovascular, respiratory and metabolic effects of buflomedil. The results indicate that the drug, at the administered dose, does not alter the patient physiological stability. An improved perfusion regimen in peripheral tissues and an optimization of cardiac energetics are also directly or indirectly implied in the results.

Aged↗

Metabolism and nutrition in surgical sepsis.

The treatment of sepsis involves, in addition to the aggression of the septic focus by antibiotic and surgical means, the support of physiological functions, in particular the metabolic-nutritional support. The Authors base the description of the relevant aspects of metabolic-nutritional support in sepsis on the results of studies performed in their Clinical Research Center and in other Centers.

Fat Emulsions, Intravenous↗

Impact of fat and glucose administration on metabolic and respiratory interactions in sepsis.

Metabolic and respiratory interactions were analyzed in a large group of septic patients (S) and in a reference group of nonseptics (NS) during the iv administration of glucose and fat. In spite of a moderate increase in CO2 production (VCO2) observed during the administration of fat in S, a VCO2-sparing effect of fat, with respect to equicaloric amounts of glucose, was reconfirmed. The relevance of the therapeutic modulation of CO2 production during parenteral nutrition, and the relative impact on the abnormal septic respiratory patterns, were emphasized by analyzing the physiological relationships and mechanisms responsible for the increase in respiratory work in sepsis.

Bacterial Infections↗

[Use of unconventional lipid substrates in parental nutrition].

In addition to the classic soybean oil fat emulsion, developed more than 40 years ago and still widely used, emulsions with other lipid substrates are available today for parenteral nutrition; these substrates implement the benefits offered by soybean oil when mixed with it in given proportions. Soybean oil triglycerides are rich in linoleic acid, a long chain omega-6 polyunsaturated fatty acid, which is essential and is an indispensable component of parenteral nutrition. However, very high doses of omega-6 polyunsaturated fatty acids should be avoided, particularly in some critical illnesses. Medium chain triglycerides, long well known to nutritionists and dietitians for their easy intestinal absorption, have become available in parenteral nutrition emulsions in a mixture with soybean oil. Medium chain triglycerides are completely and readily used for energy production and do not interfere significantly in the production of inflammatory mediators, in the composition of cell membranes and in body organ and system functions. Omega-3 polyunsaturated fatty acids, essential fatty acids derived from fish oil, permeate cell structure and affect cell activity with different mechanisms, playing also an important role in the modulation of inflammatory processes. Omega-3 emulsions in parenteral nutrition are currently added as a supplement to other fat emulsions. Knowledge of these "non-conventional" fat emulsions is being continuously improved by investigative work and clinical experience.

Adult↗

Substrate supply as determinant of O2 extraction in sepsis and nonseptic trauma.

Metabolic and hemodynamic measurements performed in 72 septic (S) and 40 nonseptic (NS) surgical patients undergoing total parenteral nutrition were analyzed to assess the role of substrate supply as a determinant of O2 extraction (O2Ex). In S, O2Ex was inversely related to cardiac index (CI); at any given CI, significant increases in O2Ex with simultaneous increases in O2 consumption (VO2) were related to increasing doses of amino acids, with a less remarkable effect of fat and no effect of glucose dose. In NS, O2Ex was also inversely related to CI; however, at any given CI, there was no evident substrate-supply dependency of O2Ex, which was more normally related to P50. The increase in VO2 per gram of administered amino acids, at any CI and O2 transport index, was 817 ml in S and 267 ml in NS. These results suggest that the impaired O2Ex and VO2 in S may at least partly reflect abnormalities in substrate utilization and that amino acid support may have a role in modulating these abnormal O2Ex patterns by providing preferential substrate for oxidative metabolism.

Adult↗

[Dynamic computed tomography in the characterization of focal hepatic lesions].

The main goal of our study was to test dynamic CT capability to characterize focal liver lesions. We examined 57 patients: 6 were affected with focal nodular hyperplasia (FNH), 19 with hepatocellular carcinoma (HCC), 1 with a regenerating nodule on cirrhosis; 14 patients had metastases, 3 focal fatty infiltration, 1 a necrotic nodule, 1 a non-Hodgkin's lymphoma, 1 a cysto-adeno-cholangiocarcinoma and 11 hemangiomas. All lesions were identified with US and the diagnosis was confirmed with the gold standard technique--that is, biopsy or surgery, and red blood cell SPECT for hemangiomas. All lesions were studied with a CT multiphase protocol consisting of a single-level dynamic phase followed by an incremental dynamic phase and finally by a delayed phase to study prolonged and delayed enhancement. Single-level dynamic bolus CT requires an injection of 60 ml nonionic contrast agent administered with a power injector into a cubital vein, at a rate of 5 ml/s. Scanning begins 10 seconds after the injection and consists of 6 series of 2 scans each; each scan lasts 2 seconds and is obtained during the same respiratory apnea, with a 5-second interscan pause. In this phase, 12 scans 5 mm thick are obtained, lasting 24 seconds in all, with pauses lasting 25 seconds--in all, 49 seconds. The next phase is the dynamic incremental scanning, to study the whole liver: this phase requires a 50-ml contrast agent injection at a rate of 4 ml/s, followed by 70 ml at a rate of 1 ml/sec, using 5 mm slice thickness and 8 mm scan interval. This results in 16 scans, beginning 20 seconds after the injection, with a scan time of 2 seconds and 4 seconds of interscan delay, 92 seconds in all. In the last phase, scanning begins 5 minutes after the injection, with a maximum delay of 10-15 minutes. Enhancement variations in both the lesions and the surroundings parenchyma, as related to time, were collected together with morphological data. Time density curves were grouped according to histologic classification and red blood cells SPECT findings; the curves were analyzed with the regression analysis. The results were obtained by analyzing a series of equations describing the different densities of the lesion and the surrounding parenchyma at fixed time intervals, integrated with morphological data, and then comparing the groups of lesions with each other. The regression analysis of the density curves and of the morphological data allowed us to correctly differentiate the 4 most frequent types of lesions--that is, hemangioma, HCC, FNH and metastasis--in 89% of the patients.

Adult↗