Direct peritoneal resuscitation reduces inflammation in the kidney after acute brain death

Cascading renal injury after brain death: Unveiling glycocalyx alteration and the potential protective role of tacrolimus

Brain death (BD) is a complex medical state that triggers systemic disturbances and a cascade of pathophysiological processes. This condition significantly impairs both kidney function and structural integrity, thereby presenting considerable challenges to graft viability and the long-term success of transplantation endeavors. Tacrolimus (FK506), an immunosuppressive drug, was used in this study to assess its impact as a pretreatment on brain death-induced renal injury. This study aimed to investigate changes associated with brain death-induced renal injury in a 4-month-old female porcine model. The experimental groups included brain death placebo-pretreated (BD; n = 9), brain death tacrolimus-pretreated using the clinical dose of 0.25 mg/kg the day before surgery, followed by 0.05 mg/kg/day 1 hour before the procedure (BD + FK506; n = 8), and control (ctrl, n = 7) piglets, which did not undergo brain death induction. Furthermore, we aimed to assess the effect of FK506 on these renal alterations through graft preconditioning. We hypothesized that immunosuppressive properties of FK506 reduce tissue inflammation and preserve the glycocalyx. Our findings revealed a series of interconnected events triggered by BD, leading to a deterioration of renal function and increased proteinuria, increased apoptosis in the vessels, glomeruli and tubules, significant leukocyte infiltration into renal tissue, and degradation of the glycocalyx in comparison with ctrl group. Importantly, treatment with FK506 demonstrated significant efficacy in attenuating these adverse effects. FK506 helped reduce apoptosis, maintain glycocalyx integrity, regulate neutrophil infiltration, and mitigate renal injury following BD. This study offers new insights into the pathophysiology of BD-induced renal injury, emphasizing the potential of FK506 pretreatment as a promising therapeutic intervention for organ preservation, through maintaining endothelial function with the additional benefit of limiting the risk of rejection.

Effects and Mechanisms of Peritoneal Resuscitation on Acute Kidney Injury After Severe Burns in Rats

INTRODUCTION

Acute kidney injury (AKI) is a common complication in severe burn patients with poor prognosis and high mortality. Reduced kidney perfusion induced by the decreased effective circulating blood volume after severe burn is a common cause of AKI. Routine intravenous resuscitation (IR) is difficult or delayed in extreme conditions such as war and disaster sites. Peritoneal resuscitation (PR) is a simple, rapid resuscitation strategy via a puncture in the abdominal wall. This study investigated whether PR is a validated resuscitation strategy for AKI after severe burns in rats and explored its mechanisms.

MATERIALS AND METHODS

Eighty Sprague-Dawley rats were randomized into four groups: (1) sham group; (2) IR group, which was characterized by the full thickness burn of 50% of the total body surface area received IR immediately post-injury; (3) early PR group, in which rats with the same burn model received PR immediately post-injury; and (4) delayed resuscitation (DR) group, in which rats with the same burn model received no resuscitation within 3-hour post-injury. PR and DR groups animals received IR after 3-hour post-injury. The survival rate, mean arterial pressure, renal histopathology, renal function, indicators of renal injury, and renal hypoxia-inducible factor-1α and NADPH oxidase 4 (NOX4) proteins of rats were measured at 3 h, 12 h, and 24 h post-injury.

RESULTS

Compared with rats in the DR group, rats in the PR group had a significantly improved survival rate (100% vs. 58.3% at 24 h, P = 0.0087), an increased mean arterial pressure (92.6 ± 6.6 vs. 65.3 ± 10.7, 85.1 ± 5.7 vs. 61.1 ± 6.9, 90.1 ± 8.7 vs. 74.9 ± 7.4 mmHg, at 3 h, 12 h, and 24 h, P < 0.01), a reduced renal water content rate (51.6% ± 5.0% vs. 70.1% ± 6.8%, 57.6% ± 7.7% vs. 69.5% ± 8.7%, at 12 h and 24 h, P < 0.01), attenuated histopathological damage, reduced serum creatinine expression (36.36 ± 4.27 vs. 49.98 ± 2.42, 52.29 ± 4.31 vs. 71.32 ± 5.2, 45.25 ± 2.55 vs. 81.15 ± 6.44 μmol/L, at 3 h, 12 h, and 24 h, P < 0.01) and BUN expression (7.62 ± 0.30 vs. 10.80 ± 0.58, 8.61 ± 0.32 vs. 28.58 ± 1.99, 8.09 ± 0.99 vs. 20.95 ± 1.02 mmol/L, at 3 h, 12 h, and 24 h, P < 0.01), increased kidney injury markers neutrophil gelatinase-associated lipocalin expression (95.09 ± 7.02 vs. 101.75 ± 6.23, 146.77 ± 11.54 vs. 190.03 ± 9.87, 112.79 ± 15.8 vs. 194.43 ± 11.47 ng/mL, at 3 h, 12 h, and 24 h, P < 0.01) and cystatin C expression (0.185 ± 0.006 vs. 0.197 ± 0.006, 0.345 ± 0.036 vs. 0.382 ± 0.013, 0.297 ± 0.012 vs. 0.371 ± 0.028 ng/mL, at 3 h, 12 h, and 24 h, P < 0.01), and reduced renal hypoxia-inducible factor-1α and NADPH oxidase 4 protein expression (P < 0.01). There was no significant difference between rats in the PR group and the IR group in the above indicators.

CONCLUSIONS

Early PR could protect severe burn injury rats from AKI. It may be an alternative resuscitation strategy in severe burn injury when IR cannot be achieved.

Direct Peritoneal Resuscitation for Trauma

Direct peritoneal resuscitation (DPR) has been found to be a useful adjunct in the management of critically ill trauma patients. DPR is performed following damage control surgery by leaving a surgical drain in the mesentery, placing a temporary abdominal closure, and postoperatively running peritoneal dialysis solution through the surgical drain with removal through the temporary closure. In the original animal models, the peritoneal dialysate infusion was found to augment visceral microcirculatory blood flow reducing the ischemic insult that occurs following hemorrhagic shock. DPR was also found to minimize the aberrant immune response that occurs secondary to shock and contributes to multisystem organ dysfunction. In the subsequent human trials, performing DPR had significant effects in several key categories. Traumatically injured patients who received DPR had a significantly shorter time to definitive fascial closure, had a higher likelihood of achieving primary fascial closure, and experienced fewer abdominal complications. The use of DPR has been further expanded as a useful adjunct for emergency general surgery patients and in the pretransplant care of human cadaver organ donors.

The role of direct peritoneal resuscitation in the treatment of hemorrhagic shock after trauma and in emergency acute care surgery: a systematic review

PURPOSE

Direct peritoneal resuscitation (DPR) has been used to help preserve microcirculation by reversing vasoconstriction and hypoperfusion associated with the pathophysiological process of shock, which can occur despite appropriate intravenous resuscitation. This approach depends on infusing a hyperosmolar solution intraperitoneally via a percutaneous catheter with the tip ending near the pelvis or the root of the mesentery. The abdomen is usually left open with a negative pressure abdominal dressing to continuously evacuate the infused dialysate. Hypertonicity of the solution triggers visceral vasodilation to help maintain blood flow, even during shock, and is also associated with reduced local inflammatory cytokines and other mediators, preservation of endothelial cell function, and mitigation of organ edema and necrosis. It also has a direct effect on liver perfusion and edema, more rapidly corrects electrolyte abnormalities compared to intravenous resuscitation alone, and may requireless intravenous fluid to stabilize blood pressure, all of which shortens the time required to close patients' abdomen.

METHODS

An online query using the search term "direct peritoneal resuscitation" was carried out in PubMed, MEDLINE and SciELO, limited to publications indexed from January 2014 to June 2020. Of the 20 articles returned, full text was able to be obtained for 19. A manual review of included articles' references was resulted in the addition of 1 article, for a total of 20 included articles.

RESULTS

The 20 articles were comprised of 15 animal studies, 4 clinical studies,and 1 expert opinion. The benefits include both local and possibly systemic effects on perfusion, hypoxia, acidosis, and inflammation, and are associated with improved outcomes and reduced complications.

CONCLUSION

DPR shows promise in patients with hemorrhagic shock, septic shock, and other conditions resulting in an open abdomen after damage control laparotomy.

Effects of negative-pressure therapy with and without ropivacaine instillation in the early evolution of severe peritonitis in pigs

PURPOSE

The abdomen is the second most common source of sepsis and secondary peritonitis, which likely lead to death. In the present study, we hypothesized that instillation of local anesthetics into the peritoneum might mitigate the systemic inflammatory response syndrome (SIRS) in the open abdomen when combined with negative-pressure therapy (NPT) to treat severe peritonitis.

METHODS

We performed a study in 21 pigs applying a model of sepsis based on ischemia/reperfusion and fecal spread into the peritoneum. The pigs were randomized into three groups, and treated for 6 h as follows: Group A: temporary abdominal closure with ABTHERA™ Open Abdomen Negative-Pressure Therapy; Group B: temporary abdominal closure with ABTHERA™ Open Abdomen Negative-Pressure Therapy plus abdominal instillation with physiological saline solution (PSS); and Group C: temporary abdominal closure with ABTHERA™ Open Abdomen Negative-Pressure Therapy plus peritoneal instillation with a solution of ropivacaine in PPS.

RESULTS

A comparison between the three groups revealed no statistically significant difference for any of the parameters registered (p > 0.05), i.e., intra-abdominal pressure, blood pressure, heart rate, O2 saturation, diuresis, body temperature, and blood levels of interleukin 6 (IL-6), tumor necrosis factor alpha (TNFα), and c-reactive protein (CRP). In addition, histological studies of the liver, ileum, kidney and lung showed no difference between groups.

CONCLUSIONS

The use of abdominal instillation (with or without ropivacaine) did not change the effect of 6 h of NPT after sepsis in animals with open abdomen. The absence of adverse effects suggests that longer treatments should be tested.