Loading...
Please wait, while we are loading the content...
Similar Documents
The Discocyte-Echinocyte Transformation as an Index of Human Red Cell Trauma
| Content Provider | Semantic Scholar |
|---|---|
| Author | Black, Keith L. Jones, Richard D. P. |
| Copyright Year | 1976 |
| Abstract | Scanning electron microscopic observation of blood samples before, during and after cardiopulmonary bypass during cardiovascular surgery revealed that 4 to 25% of the red blood cells undergo a progressive transformation of discocyte to echinocyte. A morphological index, I, was developed and the change in I (Ir) was found to correlate well with measurements of free plasma hemoglobin. Incubation of blood samples form normal subjects for 90 minutes at 37°C resulted in no increase in Ir whereas incubated samples from patients following cardiopulmonary bypass showed an increased Ir to a mean value of 1140 ±185. Incubation therefore appears to uncover sublethal red cell damage caused by extracorporeal circulation. It is suggested that this technique is a sensitive index of red cell trauma which may have useful clinical applications. OHIO J. SCI. 76(5): 225, 1976 Appreciation of the fine details of red blood cell shape can provide information of great importance; yet the various shapes that the red cell can assume are just beginning to be analyzed in a critical fashion. Until recently, red cell shape could only be studied with the optical microscope, i.e. with a limiting resolution of 0.2 micron. The situation changed with the advent of the scanning electron microscope, and we are now able to see the details of cell shape with a tenfold improvement in resolution and a depth of field that permits an appreciation of the three-dimensional shape of the cells (Salsbury and Clarke, 1967). It is the purpose of this communication to demonstrate how morphologic changes can be quantitated and used as an index of red cell trauma. MATERIALS AND METHODS Studies were carried out with the aid of MiniRapid Scan, ISI, scanning electron microscopy (SEM) on fifteen patients undergoing cardiovascular surgery. Small quantities of blood were obtained from: banked donor blood; the patients before cardiopulmonary bypass; the arterial side of the extracorporeal circuit at 15, 30 and 60 minutes of bypass; and the patients two hours post-operatively. Two or three drops of a blood sample were allowed to fall initially Manuscript received July 8, 1975 and in revised form May 31, 1976 (#75-45). into 10 ml of a 0.1% gluteraldehyde-sucrosebuffer solution (pH—7.40, 520 mOsM) for at least 30 minutes. The cells were centrifuged and resuspended in 10 ml of 3% gluteraldehyde solution where they remained for at least 60 minutes to complete fixation. Following fixation the cells were washed with Isoton (Coulter Electronics, Inc.) in order to remove any protein, salt crystals or other material that might have been deposited on the cell surface. Dehydration was accomplished by passing the cells successively through 65, 80, 90, 95 and 100% concentrations of ethyl alcohol followed by propylene oxide. A small drop of the final cell suspension in propylene oxide was then allowed to spread on a metal stub; dessication took place almost instantaneously. The cells were coated with Gold-Palladium in a vacuum evaporator to make the surface conductive for observation in the SEM. Two hundred to 400 cells of each sample were counted at a magnification of 5000 X and were classified into four types following the system of nomenclature of Bessis (1974). Since discocytes undergo a progressive transformation with the echinocyte type III representing the most severe damage (fig. 1), a morphological in: dex was calculated by arbitrarily assigning a weighting factor to each cell type as follows: discocyte, 0; echinocyte type I, 1; echinocyte type II, 2; echinocyte type III, 3. The average number of each cell type per 100 cells in the sample was multiplied by its weighting factor. The sum of these products equals the morphologic index, I, of that sample. Thus a sample with all discocyte forms would have an index, I, of 0 whereas a sample in which all cells were of echinocyte type III form would have 1 = 300. Comparison of the change in the number of |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://kb.osu.edu/dspace/bitstream/handle/1811/22399/V076N5_225.pdf;jsessionid=8482D80E21BB80CC606843D721A40F7C?sequence=1 |
| Alternate Webpage(s) | https://kb.osu.edu/bitstream/handle/1811/22399/V076N5_225.pdf?isAllowed=y&sequence=1 |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
