P2828Survival after an out-of-hospital cardiac arrest decrease over time in all Utstein categories. The importance of a long follow-up

Background

Survival beyond 1-month after an out-of-hospital cardiac arrest (OHCA) is still considered a challenge for OHCA registries and it is often unexplored. However, a longer follow-up could help to better comprehend the long-term issues of OHCA survivors.

Purpose

Our aim was to evaluate the long-term outcome after OHCA via an Utstein-based cardiac arrest registry with a long follow-up (up to 5 years).

Methods

We enrolled all the people with an OHCA of any aetiology in our Province (about 55ehz748.1138 inhabitants in northern Italy) in whom CPR was attempted. The primary endpoint was the survival at 1 month, and the secondary endpoints were the survival at 6 months and then every year until 5 years after OHCA.

Results

In the first 45 months (October 2014–June 2018) 1774 resuscitation attempts for confirmed OHCAs were enrolled. Baseline characteristics: male 59.7%; mean age of 73.4±16 years; mean EMS response time was 11:31±5:09 mins; home location 78.8%; bystander-witnessed events were 56.1%; EMS witnessed event 15.6%; bystander CPR 39.5%; AED use before EMS arrival 2.5%; medical etiology 93%; first shockable rhythm 18.2% (90.7% VF, 2.5% VT without pulse, 6.8% AED shockable). When considering survival from the event (Figure 1 – left panel), survival was significantly higher for shockable Utstein categories (p<0.001). Considering only those patients discharged alive (Figure 1 – right panel) long term survival was significantly higher (p<0.01) once again for shockable rhythms. Interestingly, in this category survival continued to decrease over time ranging about from 90% in the first year to about 80% at four years.

Figure 1

Conclusions

Our results demonstrated that survival after OHCA can change over the time in all the Utstein categories, so we believe that a longer follow-up should be encouraged by next Utstein style revision.

Incidence of graft rejection in small bowel transplanted pigs after immunosuppression withdrawal

As intestinal grafts require heavy immunosuppression, there are no reports of immunosuppression withdrawal after clinical small bowel transplantation. In this large-animal study, we investigated the occurrence of graft rejection in intestinal-transplanted pigs after withdrawal. Large-White unrelated piglets were transplanted and divided in three groups: group 1 (n = 5), intestinal transplantation (ITx) with no immunosuppression; group 2 (n = 7), Itx and 60 days of treatment with tacrolimus and mycophenolate mofetil; group 3 (n = 5), Itx and donor bone marrow infusion (DBMi) and 60 days of treatment with tacrolimus and mycophenolate mofetil. Follow-up time after withdrawal was 120 days. Group 1 pigs died of graft acute cellular rejection (ACR) after a median of 11 days. In group 2, two pigs died of ACR-related infection and another two of ACR within 90 days. The remaining three animals (43%) were sacrificed at day 180, and their grafts showed no signs of ACR. In group 3, two pigs died of ACR-related infection and one of graft versus host disease within 80 days; at day 180 the two surviving animals showed signs of chronic rejection in the allograft. This study demonstrates that total withdrawal after ITx is followed by sudden and lethal ACR (or ACR-related infection) in more than 50% of the recipients. When a tolerance-inducing strategy as DBMi is applied, lethal graft versus host disease may also occur. In group 3, the intestinal allograft, to which the recipients were partially tolerant, developed chronic rejection that was probably associated with a decline with time of donor-leukocytes chimerism, as recently demonstrated in rats.

Efficacy of Malononitrilamide FK778 in a Preclinical Model of Small Bowel Transplantation

In a swine model of orthotopic small bowel transplantation, we assessed the efficacy of combined immunosuppressive therapy with low-dose tacrolimus plus FK778, compared with high-dose tacrolimus monotherapy. The small bowel was replaced in 23 piglets: group 1 (n = 5), no immunosuppression; group 2 (n = 12), oral tacrolimus to maintain whole blood trough levels between 15 and 25 ng/mL; and group 3 (n = 6), oral FK778 4 mg/kg/d, plus oral tacrolimus to maintain whole blood trough levels between 5 and 15 ng/mL. Follow-up time was limited to 60 days. Overall survival rates at 30 and 60 days were 0% and 0% in group 1, 30% and 0% in group 2, and 66% and 66% in group 3, respectively. The median survival time was 11 days in group 1, 28 days in group 2, and more than 60 days in group 3. The differences between groups 3 and 1 and between groups 3 and 2 were statistically significant. The numbers of major bacterial infections were 19 in group 2 (1.9 episodes per animal) and 3 in group 3 (0.75 episodes per animal). The infectious-related mortality rate was 70% in group 2 (7 cases) and 0% in group 3 (P < .05). Acute cellular rejection was absent or mild in 85% of group 2 stomal biopsy specimens and in 100% of group 3 biopsy specimens. In conclusion, combination therapy of low-dose tacrolimus is potentiated by FK778 to prevent acute cellular rejection and prolong small bowel transplant survival in pigs.

[Experimental kidney transplantation: a comparison between different models]

AIM

Two different models of kidney transplantation have been compared using 3 different techniques. The kidney grafts were procured from living donors (laparoscopic or laparotomic technique) and from cadaveric donors.

METHODS

Twenty-four outbred piglets (Large White, weight range 24-27 kg) underwent kidney transplantation. We divided the recipients into 2 groups with the following characteristics: group 1 (n=12) was represented by orthopic kidney recipients whose grafts were retrieved by laparoscopic or lapartomic technique from living unrelated donors; group 2 (n=12) was constituted by heterotopic kidney recipients whose grafts were retrieved by laparotomic technique from unrelated cadaveric donors. In both groups, Grogoire-Lich technique and Politano-Laedbetter technique were used in order to perform ureteral-vescical anastomosis together with a new technique developed from our experience called Politano-Laedbetter modified. All transplanted pigs underwent double immunosoppressive steroid therapy (tacrolimus and micofenolate mofetil). The pigs were observed for 60 days.

RESULTS

The survival rates in group 1 and in group 2 were 75% (n=9) and 66% (n=8), respectively. No significative differences were noted in length of operative time, creatinemia and ureamia levels in both study groups. The Gregoire-Lich technique was associated with a higher rate of complications.

CONCLUSION

Two different experimental models of kidney transplantation are feasible in pigs. The classic technique could be combined with the orthopic one based on the type of study needed.