Cadaver Group Research Articles

Alveolar expansion itself but not continuous oxygen supply enhances postmortem preservation of pulmonary grafts.

If lungs could be retrieved for transplant after circulatory arrest, the shortage of donors might be significantly alleviated. Great controversy still exists concerning the optimal mode of preservation of pulmonary grafts in these non-heart-beating donors. Graft function was measured in an isolated room air-ventilated rabbit lung model during reperfusion with homologous, diluted (Hb +/- 8.0 g/dl) and deoxygenated (PaO2 +/- 40 mmHg) blood up to 4 h. Five groups of cadavers (n = 4 in each group) were studied: In the control group, lungs were immediately reperfused. In the other groups, cadavers were left at room temperature for 4 h after death with lungs either deflated (group 1), inflated with room air (group 2), or ventilated with room air (group 3) or 100% nitrogen (group 4). After 1 h of reperfusion, significant differences were noted between group 1 and groups 2, 3, and 4 in peak airway pressure (27 +/- 5 cm H2O vs. 15 +/- 1 cm H2O, 17 +/- 2 cm H2O, and 16 +/- 1 cm H2O, respectively; P < 0.05), in weight gain (137 +/- 24 vs. 31 +/- 7, 30 +/- 3, and 30 +/- 2%, respectively; P < 0.05), and in veno-arterial oxygen pressure gradient (9 +/- 5 vs. 95 +/- 13, 96 +/- 7 and 96 +/- 4 mmHg, respectively; P < 0.05). Also, wet-to-dry weight ratio at end of reperfusion was significantly different (10.2 +/- 1.0 vs. 6.0 +/- 0.3. 5.2 +/- 0.3 and 5.4 +/- 0.5, respectively; P < 0.05). No significant differences in any of these parameters were observed between groups 2, 3, and 4. These data suggest that: (1) pulmonary edema will develop in atelectatic lungs if reperfusion is delayed for 4 h after death; (2) postmortem room air-inflation is as good as ventilation in prolonging warm ischemic tolerance; (3) ventilation with room air is no different from that with nitrogen; (4) therefore, prevention of alveolar collapse appears to be the critical factor in protecting the warm ischemic lung from reperfusion injury independent of continuous oxygen supply.

A new formula for population-based estimation of whole body muscle mass in males.

A new equation to estimate muscle mass in males was developed using parameters common to the 1981 Canada Fitness Survey and the male cadaver data of Martin et al. (1990b). The cadavers (N = 12) were randomly divided into two groups. The equation was developed on cadaver Group A and then validated on Group B. Once the equation with the most suitable variables was validated on Group B, it was redeveloped on combined data from Groups A and B. The final equation is as follows: muscle mass (gm) = Ht (0.031MUThG2 + 0.064CCG2 + 0.089CAG2) - 3,006; adjusted R2 = .96, SEE = 1,488 gm, F = 87.5, p = .0001. Variables (in cm) were Ht, height; MUThG, modified upper thigh girth; CCG, corrected calf girth; and CAG, corrected arm girth. The predictive ability of this equation was comparable to the original equation of Martin et al. (1990b) and can be a valuable tool for muscle mass estimation of male subjects in the 1981 Canada Fitness Survey.

Retrograde cerebral perfusion: anatomic study of the distribution of blood to the brain

Despite apparently good clinical results with retrograde cerebral perfusion during operation on the aortic arch, there is still concern about the real distribution of the blood injected in the superior vena cava to the brain, especially when the internal jugular vein is valvulated (88% of the cases). This anatomic study was carried out to determine how a liquid injected in the superior vena cava reaches the brain. Three groups of adult cadavers (5, 5, and 3 cases, respectively) were injected with latex, colored blue, through a cannula in the superior vena cava. In group I, 600 mL of latex was injected. Group II was identical except that a catheter had been inserted, before the injection, into the internal jugular vein to collapse the internal jugular vein valve, when existing. In group III, the azygos vein was ligated. The internal jugular vein was not valvulated in 2 cases in group I. In those 2 cases, latex was found up to the jugular foramen. In the other cases in group I, and in all cases in group II, where the internal jugular vein was valvulated, the following veins were injected: internal jugular vein up to the valve (almost no latex beyond), azygos vein, inferior vena cava, renal veins, rachidian and perimedullar venous plexuses, and venous sinuses of the brain. In group III, no opacification was observed beyond ligated azygos vein or valvulated internal jugular vein. Despite the fact that this study was carried out on cadavers, one can assume that, during retrograde cerebral perfusion, the azygos vein system is a major way to the central nervous system when the internal jugular vein is valvulated.

SUCCESSFUL LONG-TERM OUTCOME WITH 0-HAPLOTYPE-MATCHED LIVING-RELATED KIDNEY DONORS

The waiting list for cadaver kidney transplantation continues to grow. Yet there has been little increase in the number of living-donor transplants. At many centers, willing relatives are turned down as potential donors because of poor HLA ABDR matching with the recipient. It has been our policy to accept the 0-haplotype-match (0-HTM) living-related donor. We studied long-term (6-year) outcome of 0-HTM transplants compared with the outcome of transplants from 1- and 2-HTM recipients and from cadaver donors. Since 1984, 352 adults have received primary living-related renal transplants, and had a minimum of 1 year of follow-up: 92 2-HTM, 216 1-HTM, and 44 0-HTM. In the same period and with the same follow-up, 362 adults have received primary cadaver (CAD) renal transplants. Immunosuppression consisted of cyclosporine, azathioprine, and prednisone (triple therapy) for living-donor and sequential therapy for CAD recipients. ABDR match (mean +/- SD) for 0 HTM was 1.3 +/- 8; CAD, 2.0 +/- 1.6; % peak panel-reactive antibodies (PRA) for 0 HTM was 1.2 +/- 5.3; 1 HTM, 6.7 +/- 20; 2 HTM, 7.5 +/- 21; CAD, 15.5 +/- 30. The percentage of PRA at the time of transplant for 0 HTM was .7 +/- 4.4; 1 HTM, 4.1 +/- 1.6; 2 HTM, 6 +/- 18; CAD, 7.2 +/- 20. While the number of ABDR matches was significantly fewer for 0 HTM than for the other groups, the % PRA at transplant and the peak % PRA were less in the 0-HTM group. Other demographics were not significantly different. Patient survival was significantly lower in the CAD group vs. 2-HTM recipients (P < .05). The living-related grafts had significantly greater survival than the CAD grafts (P < .05), but there was no significant difference between 0-, 1-, and 2-HTM graft survival. The most common causes of graft loss in all groups were death and chronic rejection. In our experience, the long-term graft survivals of 0-HTM and 1-HTM transplants are the same, and both are superior to CAD results, using 0-HTM living-related donor transplants should be continued and encouraged.

The influence of coracoacromial arch anatomy on rotator cuff tears

We performed an anatomic study of 140 cadaver shoulders to correlate the influence of the coracoacromial arch anatomy on full-thickness rotator cuff tears (RCTs). The presence, location, and size of RCTs were initially documented. After dissection was complete 14 dimensional parameters, including humeral head size, glenoid size, and location of bony landmarks, were obtained by direct measurement. These data were entered into a computerized data base and 24 additional parameters (lengths, angles, areas) were calculated. The data were then subjected to analysis of variance and paired and unpaired t tests to determine correlation between the multiple parameters, age, sex, and left-to-right variance with RCTs. Three-dimensional computer modeling was then used to investigate the role of humeral head position in defining the available space within the coracoacromial arch (supraspinatus outlet). Overall 20% of the cadaver group exhibited full-thickness RCTs. The age group 60 years and older had a 29% incidence of RCTs compared with 5% in the group less than 60 years of age. The RCT group had a significantly greater anterior projection of the acromion than had the intact group (difference = 3.8 mm, p < 0.007). Acromial tilt was 28.5° in the RCT group and 33.5° in the intact group (p < 0.007). The supraspinatus outlet area was calculated by determining the total coracoacromial arch area and subtracting the area of the humeral head within the coracoacromial arch. The supraspinatus outlet was 22.5% smaller in the RCT group (p < 0.07). By using a series of measured and calculated parameters, we were able to characterize the anatomy of the coracoacromial arch and its relationship with the humeral head and to correlate variations in structure with the presence of RCTs. These findings may aid in our understanding of outlet impingement as a factor in the cause of RCTs.

Age-Related Changes in Femoral Trabecular Bone in Arthrosis

Age-related changes in the cancellous bone in selected regions of the proximal femur and iliac crest were assessed. An arthrosis group and a control cadaver group, partitioned into subjects younger and older than aged 50 years, were compared. The control group comprised 69 heads of femur and iliac crest samples. The arthrosis group comprised 28 consecutive heads of femur affected by primary arthrosis and an iliac crest biopsy taken during hip arthroplasty. Cancellous bone was sampled from four selected regions in the proximal femur. Histomorphometric estimates of percentage bone volume were determined using image analysis. In the young controls the bone volume was higher than that in the old controls for all the regions. In the arthrosis group the bone volume was higher than that of the old controls except for the subchondral principal tensile and medial to the greater trochanter regions. The old controls had regression of bone volume on age for the subchondral and medial principal compressive regions and the iliac crest. The arthrosis group had a minimal dependence of bone volume on age. Our study showed that primary arthrosis modulates the age dependence of bone volume in the proximal femur.

Renal transplantation done safely without prior chronic dialysis therapy.

The complications, cost, and inconvenience associated with pretransplant hemodialysis and peritoneal dialysis would be minimized if transplantation were instituted without prior dialysis. That preuremic transplantation is safe and efficacious in patients with immanent end-stage renal disease has not been established. All 1742 consecutive primary renal transplants performed at the University of Minnesota during the 16.5 year period from January 1968 through July 1984 were reviewed to determine whether graft and patient survival were adversely affected by transplantation prior to dialytic therapy. In the overall group of primary renal transplants, no differences in actuarial graft or patient survival were noted with or without prior dialysis. Likewise, outcome was not affected by the pretransplant dialysis status in recipients of allografts from HLA-identical mismatched living-related donors. However, in cadaveric transplantation graft function appeared to be adversely affected by transplantation prior to dialysis, with 52% vs. 66% two-year graft function for nondialyzed vs. chronically dialyzed recipients, respectively (P = 0.15). Patient survival was significantly (P = .04) decreased in the nondialyzed group, with 66% vs. 80% two-year survival in the chronic dialysis group. However, nearly all of the nondialyzed, cadaveric recipients were diabetic. The outcome of transplantation was found to be identical in these patients, as compared with chronically dialyzed diabetic recipients of cadaveric grafts. Thus, the apparent detrimental effect of predialytic transplantation in the cadaver group was due to the preponderance of diabetics in the nondialyzed group. Since July 1984, a single-armed therapeutic trial of combination therapy with azathioprine, prednisone, antilymphoblast globulin (ALG), and cyclosporine has been undertaken, Since that time, 36 primary graft recipients were transplanted prior to dialysis. Of these 36, 35 currently have a functioning graft. Thus, transplantation prior to chronic dialysis is safe irrespective of donor source, or choice of immunosuppressive agents.

RENAL TRANSPLANTATION IN CHILDREN

We review our results of transplantation performed during the last 10 years in 65 children less than 15 years old: 32 parental grafts (group P) are compared with 35 grafts from well-matched (mean HLA-A,B mismatches: 1.7) cadavers (group C). Group P patients' survival is slightly but not significantly better than that of group C recipients (96.6 versus 82.7% at 5 years). Graft survival is significantly (P less than 0.02) better in group P than in group C (85.2 versus 51.2% at 5 years). At the end of the study, 3 grafts (2 from rejection) are lost in group P versus 14 (8 from rejection) in group C (P less than 0.01). The number of acute rejection episodes treated during the first 3 months is significantly lower in group P recipients. Epiphyseal osteonecrosis is observed in none of the patients of group P but in five of group C. Hypertension is significantly less frequent in group P than in group C. The results obtained in group P are attributed largely to a better non HLA-A,B compatibility, although the potential role of splenectomy performed in 25 recipients of group P and in none of group C cannot be excluded. Furthermore, the improved technical conditions inherent in living donor transplantation probably play an additional role. We conclude that in children the fate of parental kidneys is significantly better than that of cadaver transplants selected for their good HLA-A,B compatibility.

Interpretive study of kidney transplant survival data.

We analyzed Kidney Transplant Registry survival data on transplants performed before 1 January 1967. Most transplants were performed irrespective of HL-A matching and were essentially random in this regard. Semilog plots of monozygous twin (MONO), cadaver (CAD), and living unrelated donor (LUD) transplant survival data were found to conform to a linear survivorship model (model 1). Sibling (SIB) and parent-child (PAR) data conformed to a convex survivorship model (model 2). These facts suggested that subpopulations of strikingly different immunological risk existed within SIB and PAR groups, but not within MONO, CAD, or LUD groups. Graphical procedures for estimating parameters of the survivorship models are described and, using these parameters, one can partition the probability of transplant failure into four clinically useful categories: acute technical risk, acute immunological risk, chronic aspecific risk, and chronic immunological risk. This breakdown of risk factors demonstrated that the total probabilities of failure from an immunological cause were 0.00, 0.41, 0.45, 0.89, and 0.93 for MONO, SIB, PAR, CAD, and LUD groups, respectively. The probabilities of immunological rejection thus stand in approximately the same proportions as the average number of HL-A mismatches for these five groups, namely, 0, 2, 2, 4, and 4. These results encourage one to believe that a successful matching program can significantly reduce CAD immunological risk. Moreover, if matching is successful, future CAD survival data will conform to a convex model 2 locus. Other points of biological interest are mentioned, and it is suggested that the partitioning of risk described in this paper can improve the evaluation of new therapies and matching procedures.

Long-Term Integrity of Renal Function in Cadaver Allografts

In general, renal transplant recipients of cadaver kidneys fare less well than recipients of living related donor kidneys in regard to incidence of rejection episodes and stability of renal function. Specific renal function measurements of four cadaver recipients surviving a mean of 29 months without experiencing rejection are compared with those of seven well-matched living related donor recipients who have maintained optimal stability of renal function a minimum of one year following transplant. Renal function of the cadaver group compared favorably and in certain instances exceeded that of the living donor group. These data indicate that even without histocompatibility testing, transplantation of cadaver kidneys can occasionally result in a sustained preservation of renal function which closely parallels that seen in well-matched recipients. Excluding chance histocompatibility, the factors related to such therapeutic success are unknown.