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J M Tellado

Publications and source records attributed to J M Tellado.

11 recordsLinked to original sources

A clinical trial on the prevention of catheter-related sepsis using a new hub model.

BACKGROUND: Catheter hub contamination is being increasingly recognized as a source of catheter-related sepsis. The authors have investigated the efficacy of a new hub design in preventing endoluminal catheter contamination and catheter-related sepsis arising at the hub. METHODS: Adult surgical and intensive care patients requiring a subclavian catheter for at least 1 week were randomly assigned to receive catheters with standard connectors (control group, n=73) or equipped with a new hub model (new hub group, n=78). Skin, catheter tip, and hub cultures were performed at the time the catheter was withdrawn because therapy was terminated or because of suspicion of sepsis, in which case peripheral blood cultures were taken. RESULTS: Of the 151 patients included, 15 (10%) developed catheter-related sepsis. Catheters were more often withdrawn because suspicion of infection in the control group (42 vs. 19%, p<0.005). Catheter sepsis rate was higher in the control group (16 vs. 4%, p<0.01) because of the low rate of catheter sepsis arising at the hub observed in the new hub group (1 vs. 11%, p<0.01). The prevalence of culture-positive catheter hubs without associated bacteremia (colonization) was higher in the control group (18 vs. 5%, P<0.03). CONCLUSIONS: A new catheter hub has proved to be useful in preventing endoluminal bacterial colonization and catheter-related sepsis in subclavian lines inserted for a mean of 2 weeks.

Adult

Circulating and exudative polymorphonuclear neutrophil priming and oxidative capacity in anergic surgical patients.

OBJECTIVES: To examine the oxidative capacity of circulating and exudate polymorphonuclear neutrophils from reactive patients and anergic patients before surgery to determine why anergic patients have increased sepsis-related mortality once an infectious complication develops. DESIGN: Prospective in vitro patient study. SETTING: Tertiary care, major university teaching hospital. PARTICIPANTS: Surgical patients admitted for major elective gastrointestinal surgery. MAIN OUTCOME AND MEASURES: We used flow cytometry and the dye 2-7-dichlorofluorescein diacetate to measure hydrogen peroxide production of circulating and exudate polymorphonuclear neutrophils at baseline and after stimulation with Staphylococcus epidermidis. RESULTS: We found that polymorphonuclear neutrophils were primed in the intravascular space as evidenced by increased numbers of formyl-methionyl-leucyl-phenylalanine receptors, increased hydrogen peroxide production at baseline, and increased hydrogen peroxide production with stimulation. These results were more evident in the anergic patient. After exudation, anergic polymorphonuclear neutrophils lost most of their capacity to produce additional hydrogen peroxide. CONCLUSIONS: The data suggest that this intravascular priming adversely affected polymorphonuclear neutrophils during exudation, more marked in the anergic patient, and may contribute to the sepsis-related mortality of the anergic patients.

Aged

Decreased polymorphonuclear leukocyte exudation in critically ill anergic patients associated with increased adhesion receptor expression.

OBJECTIVE: To determine the mechanism for the reduced polymorphonuclear leukocyte exudation in critically ill anergic patients. DESIGN: Prospective consecutive patient study. SETTING: Tertiary care surgical intensive care unit. PATIENTS: Eighteen patients with intra-abdominal injections were studied. INTERVENTIONS: Critically ill patients were stratified based on their delayed type hypersensitivity response to ubiquitous antigens. Polymorphonuclear leukocytes were isolated from blood and from exudate blister type skin windows. Adhesion and chemotactic surface receptors were measured, as was cytokine content and chemoattraction capacity of skin window fluid for control neutrophils. MEASUREMENTS AND MAIN RESULTS: Circulating neutrophils from anergic patients have increased CR3 adherence receptors compared with those neutrophils from reactive patients. f-met-leu-phe receptors are equal in number and C5a receptors are either significantly reduced in number or occupied with ligand. This same receptor pattern is maintained after neutrophil exudation in both patient groups. Serum and skin window fluid from anergic patients attracted less neutrophils in vitro and in vivo. CONCLUSIONS: These data suggest two possible mechanisms for the reduced neutrophil delivery of critically ill anergic patients: a receptor-mediated increased adherence to vascular endothelium preventing diapedesis; reduced chemo-attraction potential of serum, and possibly, exudate fluid.

Adult

Activation state of polymorphonuclear leukocytes in surgical patients: characterization of surface receptor expression.

BACKGROUND: We studied the expression of chemotactic, opsonic, and adherent receptors on the membranes of polymorphonuclear neutrophils (PMNs) from surgical patients because modulation of these receptors has been suggested in the control of critical PMN functions that directly or indirectly influence patient outcome. METHODS: Healthy subjects who had PMN adherence, chemotaxis, and receptor measurements were compared with preoperative surgical patients and those who were within 48 hours of an admission to an intensive care unit (surgical intensive care unit) because of an acute illness. RESULTS: The following receptor/cell pattern was found in control subjects, preoperative patients, and patients in the surgical intensive care unit, respectively: formyl peptide (13,000 vs 18,000 vs 22,000), CR3 (59,000 vs 105,000 vs 121,000), fibronectin (21,000 vs 20,000 vs 35,000), FcII gamma (9,000 vs 20,000 vs 25,000), C5a (347 vs 265 vs 250 mean channel number), and FcIIIR (64,000 vs 75,000 vs 26,000). This receptor pattern was partly correlated directly or indirectly with the acute-phase response, neutrophil adherence, and PMN chemotaxis from these subjects. CONCLUSIONS: The data suggest that there are alterations in the expression and modulation of PMN surface membrane receptors in patients with a "stable" disease process compared with those with an acute illness, which may affect critical PMN functions needed to combat bacterial infections.

Adolescent

Altered neutrophil function following reperfusion of an ischemic myocutaneous flap.

The neutrophil has been implicated as a source of oxygen free radicals provoking the reperfusion injury in various ischemic organs. This provided the motivation to explore the pathophysiologic role of the neutrophil in a swine model of postischemic latissimus dorsi myocutaneous flaps. Neutrophil function, neutrophil sequestration, and the anatomic distribution of muscle injury were estimated following a 6- to 8-hour global ischemic insult. Neutrophil function as measured by phorbol myristate acetate-stimulated superoxide production was found to be enhanced on reperfusion of ischemic flaps (n = 17). Neutrophil sequestration estimated from the arterial-venous difference of flap blood (n = 12) demonstrated that postischemic flaps more avidly sequester neutrophils than nonischemic flaps. The anatomic distribution of muscle injury (n = 7) was predominantly localized to the proximal portion of the ischemic flap. The enhanced functional response exhibited by neutrophils reperfusing an ischemic myocutaneous flap supports an active neutrophil role in the mediation of reperfusion injury.

Analysis of Variance

Critically ill anergic patients demonstrate polymorphonuclear neutrophil activation in the intravascular compartment with decreased cell delivery to inflammatory focci.

Skin test anergy, the failure to produce a delayed type hypersensitivity (DTH) response, is associated with an increase in infection-related complications and death usually due to multiple organ failure (MOF). Refractory intravascular activation of polymorphonuclear neutrophils (PMNs) has been implicated in the development of MOF. We studied 20 critically ill surgical patients with life threatening infections to determine if PMN intravascular activation was present and how this affected essential PMN functions such as exudation. The 11 anergic patients had a more intense inflammatory response to their infection. Plasma lactoferrin was 6.1 +/- 0.3 microgram/ml in anergic patients compared to 3.9 +/- 1.5 in reactive P less than 0.05, accompanied by reduced total primary (3.3 +/- 1.9 vs 4.7 +/- 2.1 micrograms/10(6) PMN P less than 0.01) and secondary (2.8 +/- 0.4 vs 5.0 +/- 0.9 microgram/10(6) PMN P less than 0.01) granule content, respectively. In vitro superoxide production following 100 ng/ml PMA stimulation was 0.44 +/- 0.1 in anergics vs 0.36 +/- 0.1 nmol/microgram PMN protein in reactivities, P less than 0.05. PMN chemotaxis was 8.2 +/- 0.6 PMNs/HPF in anergics compared to 10.2 +/- 1.6 PMNs/HPF in reactives P less than 0.05, accompanied by decreased PMN delivery to skin blister windows (3.2 +/- 1.4 vs 4.5 +/- 1.9 x 10(7) PMN/ml, respectively, P less than 0.05). We conclude that critically ill anergic surgical patients have increased intravascular PMN activation, which may contribute to oxygen-derived tissue damage in the vascular space, as well as a deficient delivery of effector cells in areas of bacterial invasion. This may lead to inability to clear the inflammatory signals which set up the vicious circle of MOF leading to death.

Cell Adhesion

Anergic patients before elective surgery have enhanced nonspecific host-defense capacity.

Albeit anergy in patients before surgery is associated with an increase in septic-related complications and mortality, it is not clear whether this is due to a downregulated nonspecific host defense or a specific cellular immune defect. We studied polymorphonuclear leukocyte neutrophil (PMN) function in 14 patients who were admitted for elective surgery and compared them with 5 healthy controls. At admission, patients were classified according to their delayed-type hypersensitivity skin test response into reactive or anergic groups. In vivo PMN delivery to skin windows, the plasma lactoferrin level, serum and skin window fluid chemoattractant activity, and in vitro superoxide production were measured. Compared with reactive patients, anergic patients showed an increased cell delivery (8.7 x 10(6) PMNs per well vs 1.6 x 10(6) PMNs per well), an increased plasma lactoferrin level (4.4 +/- 1.5 mg/L vs 3.1 +/- 0.8 mg/L), an increased chemoattractant capacity of serum and skin window fluid (38 +/- 21 cells per high-power field vs 16.8 +/- 7.2 cells per high-power field), and an increased superoxide production. We concluded that nonspecific host defense, as reflected by PMNs, is enhanced in anergic patients before surgery and may not explain the increased susceptibility to infection.

Adult

Predicting mortality based on body composition analysis.

The role of the Nae/Ke ratio (the ratio of exchangeable sodium to exchangeable potassium) was examined as a nutritional marker in surgical patients in relation to anthropometrical and biochemical indexes by its ability to identify patients at risk for mortality after hospitalization. In 73 patients with sepsis and malnutrition (Training Group, Madrid) the following were determined: percentage of recent weight loss, triceps skin fold, midarm muscle circumference, serum albumin, serum transferrin, delayed hypersensitivity skin test response, total lymphocytes, and Nae/Ke ratio by multiple isotope dilution. The predictive power of Nae/Ke ratio was so strong (F = 105.1; p less than 0.00001) that it displaced anthropometric, biochemical, and immunologic variables from the linear equation derived from stepwise discriminant analysis using hospital mortality as the dependent variable. A theoretical curve of expected deaths was developed, based on an equation obtained by logistic regression analysis: Pr/death/ = 1/(1 + e[11.8-5.2 Nae/Ke]). Pre- and post-test probabilities on that curve allowed us to determine two cut-off values, Nae/Ke ratios of 1.5 and 2.5, which were markers for nonrisk and mortality, respectively. The model was tested in a heterogeneous data base of surgical patients (n = 417) in another hospital (Validation Group, Montreal). For patients exhibiting an abnormal Nae/Ke ratio (greater than 1.2) and a greater than 10% of probability of death, 54 deaths were expected and 53 observed (X2 = 1.8 NS). Two tests confirmed the basic agreement between the model and its performance, a G statistic of -0.704 and the area beneath the "receiver-operating-characteristic" (ROC) curve (Az = 0.904 + 0.0516 for the Madrid group vs. Az = 0.915 + 0.0349 for the Montreal group, NS). It was concluded from this analysis that, compared with the usual anthropometric measurements, the Nae/Ke ratio, if available, is the best method for identifying malnourished patients at risk of dying.

Adolescent

In vitro polymorphonuclear neutrophil function in surgical patients does not correlate with anergy but with "activating" processes such as sepsis or trauma.

We studied 199 preoperative patients admitted for esophagogastric, gastric, colonic, or rectal resections, 132 patients with severe blunt trauma, 180 surgical intensive care unit patients with major sepsis, and 95 laboratory controls in order to clarify the role of polymorphonuclear neutrophil (PMN) adherence and chemotaxis to outcome. Patients were also stratified by the delayed-type hypersensitivity response to five ubiquitous antigens. PMN adherence and PMN chemotaxis were not different in preoperative reactive or anergic patients and were equal to the control values, whereas both reactive patients and anergic patients showed altered PMN function after trauma or sepsis. There was no difference in PMN adherence or chemotaxis between patients who died and those who lived. Multiple logistic regression analysis showed that patient age, delayed-type hypersensitivity, and admission serum albumin level, not PMN adherence or chemotaxis, were significantly related to septic mortality. We concluded that altered circulating PMN adherence and chemotaxis is seen in all patients after an "activation" event such as trauma or sepsis. This is a nonspecific immune alteration not related to specific immune events such as delayed-type hypersensitivity; it does not correlate with patient outcome and should not be used as a predictive variable.

Adult

The anergic state as a predictor of pancreatic sepsis.

From 1984 to 1987, 187 patients with acute pancreatitis (AP) were studied. All patients were stratified according to Ranson's criteria upon admission and were followed up by performing a CT scan weekly. One hundred and thirty-eight patients had 3 or less Ranson's criteria (non-severe acute pancreatitis = NSAP) and 49 presented 4 or more (severe acute pancreatitis = SAP). Ninety-six percent of the patients with (p less than 0.0001). Of the 49 patients with SAP, 39 developed pancreatic or peripancreatic NSAP were reactive to skin tests on the third week, while 4% remained anergic necrosis and were operated. Twenty-two of these patients had positive cultures demonstrating the presence of bacteria in the tissue samples. One hundred percent of the infected patients remained anergic until surgery, while only 40% of those with negative cultures remained anergic (p less than 0.05). Mortality rate correlated well with skin test responses, being 31% in anergic patients while only 5% in reactive subjects. Sustained anergic state (AS), sequentially checked, is associated with a high incidence of pancreatic sepsis.

Acute Disease