Arquivos Diários: 9 março, 2021

Liver Uptake on Cadaveric Donors for Transplant

Since the initial descriptions of orthotopic liver transplantation (OLT) in the 1960s, both the number of patients receiving transplants and the indications for the procedure have increased significantly. OLT represents the only treatment modality for many patients with a diverse spectrum of disease, with the predominant common factor end-stage liver failure. Advances in perioperative care of the donor and recipient, organ preservation methods, and surgical techniques have resulted in a 5 year overall survival of 78% for all recipients (Kim et al, 2015).

OPERATIVE TECHNIQUES
The first published description of human liver transplantation was by Starzl and colleagues in 1963 at the University of Colorado. In this seminal paper, the dismal outcomes of three OLT recipients were described, including one intraoperative death from uncorrectable coagulopathy and two survivors of 7 and 22 days. In addition to the pioneering conceptual framework and implementation of LT, the advanced techniques included grafts from non–heart-beating donors, venovenous bypass in the recipients, choledochocholedochostomy, and coagulation monitoring by using thromboelastography (TEG). Many of these concepts remain or have reentered the realm of LT more than 40 years after their initial description. Based largely on the initial body of work by Starzl and colleagues, this section describes the surgical procedures commonly used worlwide.

Liver Uptake on Cadaveric Donors for Transplant

The typical deceased donor has had a catastrophic head injury or an intracerebral bleed, with brain death but without multisystem organ failure. Electrolyte imbalance and hepatic steatosis in the donor are predictors of graft nonfunction. A “donor risk index” has been derived to assess the likelihood of good graft function. Key adverse factors include older donor age (especially >60 years of age), use of a split or partial graft, and a non–heart-beating donor, from which the organs are harvested after the donor’s cardiac output ceases, in contrast to the more typical deceased donation in which the organs are harvested prior to cardiovascular collapse. Use of non–heart-beating donors is associated with reduced rates of long-term graft survival and increased risk of biliary complications, which correlate with the duration of “warm ischemia” after cardiovascular collapse and before retrieval of the organ. With the critical shortage of deceased organ donors, expansion of the donor pool has included acceptance of donors 70 years of age and older for selected recipients. Prior to hepatectomy, the harvesting team makes a visual and, if necessary, histologic assessment of the donor organ. Particular attention is paid to anatomic variants in the hepatic artery that may complicate the graft arterial anastomosis in the recipient. Once donor circulation is interrupted, the organ is rapidly infused with a cold preservation solution (e.g., University of Wisconsin, histidine-tryptophan-ketoglutarate, or Institut Georges Lopez solution). Donor iliac arteries and veins are also retrieved in case vascular grafting is required. After its arrival at the recipient institution, further vascular dissection, with arterial reconstruction if necessary, is performed before implantation.

Future Perspectives

Major challenges remain in LT, including the shortage of donor organs, threat of recurrent disease, and morbidity associated with lifelong therapeutic immunosuppression. Nevertheless, the availability of LT has transformed the lives of patients with advancing liver disease and their health care providers from an ultimately futile effort to manage the complications of cirrhosis into a life-prolonging and life-enhancing intervention.

Necrotizing Gallstone Pancreatitis

The AGA recently published a Clinical Practice Update reviewing the best available evidence on pancreatic necrosis, regardless of cause. The update provides 15 best practice advice points that include the need for multidisciplinary care coordination and referral to a tertiary-care center as appropriate. The update describes supportive care, avoidance of prophylactic antibiotics, and optimization of nutrition. In addition, there is an included algorithm for the management of pancreatic necrosis requiring debridement. Debridement within the early acute phase of pancreatitis (within the first 2–4 weeks) should be avoided if possible secondary to increased morbidity and mortality. Intervention in the late phase (> 2–4 weeks) is indicated for patients with infected necrosis or persistent organ dysfunction and failure to thrive. Multiple approaches are available for the management of infected necrosis, including but not limited to percutaneous, endoscopic, or laparoscopic transgastric, or open debridement. In addition, a combination approach using percutaneous drainage followed by videoscopic retroperitoneal debridement or step-up approach can also be used. Since the publication of a multicenter RCT (PANTER) in 2010, the step-up approach for necrotizing pancreatitis has been increasingly used.

Necrotizing Gallstone Pancreatitis

The step-up approach or video-assisted retroperitoneal debridement (VARD) is a minimally invasive technique that begins with percutaneous drain placement for necrotizing pancreatitis followed by a minimally invasive retroperitoneal necrosectomy. Patients who underwent the step-up approach versus open necrosectomy had less multiple-organ failure, incisional hernias, and newonset diabetes, but no difference in mortality. The 2020 AGA Clinical Practice Update on the management of pancreatic necrosis suggests that best practice is that ‘‘minimally invasive operative approaches to the debridement of acute necrotizing pancreatitis are preferred to open surgical necrosectomy when possible, given lower morbidity’’. However, the update also notes that open necrosectomy still has a role in the modern management of acute necrotizing pancreatitis, particularly for cases whereby less invasive techniques are not feasible.

Pancreatic Surgery
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