Biomedical subjects

R C DeWeese

Publications and source records attributed to R C DeWeese.

4 recordsLinked to original sources

PubMed1995

Transpyloric passage of feeding tubes in patients with head injuries does not decrease complications.

Early enteral nutrition is reported to improve outcome of patients with severe closed head injuries (CHI). The efficacy and safety of nasoenteric tube (NET) feeds, however, has been questioned; the risk of aspiration is the major concern. Our purpose was to determine the rate of transpyloric migration, the efficacy of adjunctive measures to promote passage, and the effect on pulmonary complications. Seventy-four consecutive patients with moderate to severe CHI received enteral nutrition. Glasgow Coma Scale (GSC) score was 5.2 on admission and 6.9 at 48 hours. NETs were placed an average of 5.6 days after admission; an average of three abdominal films per patient were used to assess tube position. No patients had endoscopic NET placement during this period. Ten patients required fluoroscopic placement after failure to pass spontaneously by 5 days. Overall, transpyloric passage was achieved in 32 patients (43%), whereas 42 (57%) remained intragastric. There were no differences between the postpyloric and intragastric groups in days to full feeding (5 vs. 7 days), ventilator days (11.9 vs. 12.5), intensive care unit length of stay (15.5 vs. 15.1), or incidence of pneumonia (81 vs. 69%) or aspiration (6 vs 7%). Sixty-two patients (83%) were transferred to extended care facilities and 50 (68%) were still receiving NET feedings. Spontaneous transpyloric passage of NET occurred in less than one-half of patients with severe CHI. The routine use of adjunctive measures to promote transpyloric passage was not particularly successful, had no obvious benefit, and therefore may not be necessary.

Adolescent↗

PubMed1990

An experimental assessment of the effect of blood transfusion on susceptibility to bacterial infection.

Clinical investigations in patients who have undergone transplantation and patients with cancer and infection suggest that blood transfusions have an immunosuppressive effect. To investigate the impact on responses to infection, an experimental transfusion model was developed in the rat with allogeneic or syngeneic transfusions. Animals were given either a moderate or severe bacterial challenge, both simulating a clinical surgical infection, immediately after transfusion or 1 week later; hypotension and hemodilution were especially avoided. Blood transfusion adversely affected the animals' capacity to resist immediate moderate challenge, but not a later one. The effect was maximized by allogeneic transfusion but was not demonstrable after severe bacterial challenge, whether immediate or late.

Animals↗

PubMed1989

Experimental and clinical significance of endotoxin-dependent HLA-DR expression on monocytes.

For much of the last decade, an increasing number of surgeons have been interested in objective assessment of cellular contributors to host defense function. In order to study many of these processes, it is apparently desirable that the cells be isolated to the extent feasible for the purpose of analyzing a more or less pure population of cellular elements. The purpose of this paper is to describe the physiologic activation of mononuclear cells that occurs as a result of the isolation process. Therefore, it follows logically that such cells are therein intrinsically less responsive to further physiologic manipulation in vitro. Analyses of such data without an awareness of this intrinsic aberration will undoubtedly lead to misinterpretation of the capacity of such cells for further modulation by immunostimulants or by the intrinsic processes related to injury, anesthesia, and operation. Furthermore, it may indicate that certain agents, e.g., cytokines, are unable to stimulate cellular function when, in fact, the defense function of the cell has been initially stimulated by the isolation procedure. Fractionation of human peripheral blood over Hypaque-Ficoll and subsequent purification of monocytes by adherence to plastic lead to an increase in the relative density of HLA-DR on monocytes. This increase occurred when carried out in endotoxin lipopolysaccharide (LPS)-contaminated or LPS-depleted reagents. LPS, added experimentally to whole blood, enhanced HLA-DR expression on monocytes without further manipulation. Monocyte HLA-DR expression measured in whole blood was reduced in patients with major sepsis (n = 19) compared to normal subjects (n = 10).(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies↗

PubMed1989

Evaluation of copovithane as a nonspecific immunomodulator in surgically simulated sepsis.

Copovithane (CPV), a synthetic polymer, has been shown to have antitumor activity and also to reduce mortality in experimental murine peritonitis. The purpose of this study was to compare CPV with muramyl dipeptide (MDP), an immunomodulator of proven efficacy in simulated surgical infection. Six groups of CBA/J mice were compared; they received intramuscular injections of normal saline (controls), MDP (100 micrograms), or CPV (100, 200, and 400 mg/kg) 24 h prior to bacterial challenge. The challenge consisted of a Klebsiella-impregnated thigh suture. The first experiment assessed survival after bacterial challenge. The MDP and the CPV groups both had median survival times of 3 days, significantly longer than the control group (1 day, p less than .05). In the second experiment, animals were sacrificed at 6, 24, and 48 h following bacterial challenge, and blood and infected muscle were taken for quantitative bacteriology. At 6 h, there was no difference between groups. Both the MDP and CPV groups had significantly (p less than .05) lower blood bacterial counts than the control group at 24 and 48 h. Both the MDP and CVP groups had significantly lower local bacterial recovery than controls at 48 h (p less than .05), and local bacterial recovery of the MDP group was significantly lower than the control group at 24 h (p less than .05). CPV improved survival and reduced local and systemic bacterial recovery compared with controls. Although the effect of CPV was similar to MDP in this model, it consistently was of lower magnitude and had a narrow dose range.

Acetylmuramyl-Alanyl-Isoglutamine↗