PMN-related parameters for the monitoring of wound healing in traumatology.

In the search for objective methods to monitor the course of wound healing, the proteinase PMN elastase (n=56 pat.), the lipid peroxidation product malondialdehyde (MDA) (n=18 pat.), and polymorphonuclear neutrophil granulocytes (PMN) migratory behaviour were measured [1, 6, 7, 11]. This "stimulated PMN-locomotion" was quantified by a new PMN migration filter assay (n=10 pat.) [2]. We determined the clinical course during "per primam (pp)" wound healing (group 1), "pp" wound healing with secondary inflammatory disease (group 2), manifestation of a bacterial wound infection during healing-"per secundam (ps)" (group 3) and manifest wound infection ("ps") at the time of admission (group 4).In group 1 PMN elastase returned to normal values on the 10th postsurgical day. Median values in group 3 reflected a highly significant difference (p<0,01) on day 4 and 5 compared with group 1. In group 2 and 4 medians reflected consistent high values without reaching normal ranges throughout. MDA did not exceed the normal range in group 1, in group 3 low levels persisted, and in group 4 a recurring increase was noticed.The total migration index median (TMI) in Group I, which quantifies the percentage of stimulated PMN, reflected its highest value immediately post-surgically and dropped to the lowest on the 13th postsurgical day (decrease by 54%). The mean invasion depth (T/2), a parameter of PMN distribution, showed only slight variation with time. In a group 3-patient, T/2 reflected a maximal migratory stimulation on day 6, 4 days before clinical infection signs could be noticed; then it dropped to the lowest on day 10. This decrease probably reflects a PMN behavioural change from migration to phagocytosis [9].

Assay of phagocyte activation by means of malondialdehyde and luminol-enhanced chemiluminescence during uneventful wound healing following trauma surgery.

The purpose of the study was the assessment of the acute inflammatory response in patients (N = 12) with comparable trauma severity and uneventful wound healing courses in the postsurgical period as a contribution to the search for objectifiable criteria in the monitoring of wound healing. Whole blood chemiluminescence (CL) on the one hand and the lipid peroxidation product malondialdehyde (MDA) on the other hand as tools for the detection of the respiratory burst activity of phagocytes were used as inflammation markers and were compared with the established marker PMN elastase. Blood samples were withdrawn daily from the day of surgery to the 14th postsurgical day. CL-parameters and PMN elastase increased postoperatively reflecting surgical trauma, while MDA remained within the normal range during the whole time of observation. A decrease of CL-activity in the postsurgical period correlated with decreasing PMN elastase levels (r = 0.52, P<0.0001) as well as with the tapering of local inflammation signs concerning the wound situs. MDA values neither correlated with PMN elastase nor with any CL-parameters. The results indicate that the measurement of the phagocytic activation by CL, used for the first time in traumatology to monitor wound healing, represents a promising marker for the assessment of the actual inflammatory status.

Lipid peroxidation in open-heart surgery.

Production of oxygen free radicals and subsequent lipid peroxidation are thought to occur during cardiopulmonary bypass (CPB) and myocardial ischaemia-reperfusion injury. Malondialdehyde (MDA), a lipid peroxidation product, was measured simultaneously in arterial and coronary sinus blood before CPB and after release of the aortic crossclamp. Additional arterial samples were drawn pre-, per-, and postoperatively. Thirteen patients scheduled for coronary artery and/or valvular surgery were studied. Cold, crystalloid, cardioplegic arrest (54 [35-120] minutes, median [range]) was induced retrogradely. Preoperatively, arterial MDA was 0.78 +/- 0.4 (mean +/- SD) mumol/l, and increased during CPB (highest level 3.66 +/- 1.08 mumol/l, p < 0.002, 30 minutes after the start of reperfusion). Arterial MDA was still increased four hours after the end of CPB (3.17 +/- 0.88 mumol/l, p < 0.003), but had returned to normal the first postoperative day. No difference was found between arterial and coronary sinus samples at any time. In conclusion, MDA increased in arterial blood during CPB, indicating that lipid peroxidation occurred. There was no intracoronary release of MDA during reperfusion of the ischaemic heart.

[Biochemical wound monitoring. PMN elastase in different healing stages after trauma surgery-orthopedic interventions]. / Biochemisches Wundmonitoring. Die PMN-Elastase bei unterschiedlichen Heilungsverläufen nach unfallchirurgisch-orthopädischen Eingriffen.

Laboratory parameters are of proven value in the diagnosis of early postsurgical infections, since clinical aspects cannot always be clearly defined. Neutrophil granulocytes (PMN) are major inflammatory cells taking effect following ingestion and degradation of foreign material, such as bacteria and cell debris, for example after mechanical trauma. In patients who had undergone surgery we monitored the course of plasma PMN elastase in uncomplicated wound healing (n = 22), in uncomplicated wound healing associated with secondary infections (n = 6), and in defective wound healing (manifestation of a bacterial wound infection: n = 3; wound infection already manifest at the time of entry on study: n = 11). Surgical trauma was accompanied by an increase in PMN elastase and C-reactive protein (CRP) in all patients studied, reaching a maximum within the first 3 postsurgical days. When a bacterial wound infection became manifest during the course of healing there was a highly significant difference on the 4th postsurgical day (p < 0.01) compared with the group with uncomplicated healing. Since PMN elastase can now be determined automatically with an autoanalyser and a commercial kit and its discriminatory time point is as soon as 4-5 days after surgery, it is suggested that this marker should be determined routinely together with CRP in traumatology.

Detection of 4-hydroxynonenal as a product of lipid peroxidation in native Ehrlich ascites tumor cells.

4-Hydroxynonenal, which is a major product of lipid peroxidation in rat liver microsomes, was detected in native Ehrlich ascites tumor cells. Its formation was stimulated either by ferrous ions or by Fe(II)-histidinate. The identification was based on chromatographic (TLC/HPLC) and ultraviolet-spectroscopic evidence using synthetic 4-hydroxynonenal as reference. Highest values of 4-hydroxynonenal concentration (about 0.1 microM in the cell suspension) after 30 min of incubation were observed with Fe(II)-histidinate as stimulant. Saturation was already reached after an incubation period of 10 min. The results confirm the expectation by Schauenstein and Esterbauer (in Submolecular Biology and Cancer, Ciba Foundation Series 67 (1979) pp. 225-244, Excerpta Medica, Amsterdam) that endogenous lipid peroxidation gives rise to a distinct intracellular level of alpha, beta-unsaturated aldehydes. A simple hypothetical mechanism for the formation of 4-hydroxynonenal from n-6-polyunsaturated fatty acids is presented.