COMMON INDEX PROCEDURES USED IN TRANSPLANT SURGERIES

Transplant surgery is a complex and highly specialized field, offering life-saving treatment for patients with end-stage organ disease. While the organ transplant itself is the definitive procedure, its success often relies on a foundation of other critical surgical interventions. These “index procedures” represent fundamental skills and common access points essential for both managing patients awaiting transplant and facilitating the transplant process. This guide outlines the key steps involved in four such index procedures: Insertion of a Peritoneal Dialysis Catheter, Creation of an Arteriovenous Fistula, Multiorgan Deceased Donor Organ Retrieval (Kidney, Liver, and Pancreas), and Kidney Transplantation.

Patients with end-stage organ failure often require support therapies before transplantation becomes an option. For kidney failure, these therapies include various forms of dialysis, which necessitate surgical access. Furthermore, the process of transplantation involves the precise and coordinated retrieval of organs from donors, followed by their meticulous implantation into the recipient. Mastery of these distinct surgical procedures is paramount for transplant surgeons and the multidisciplinary teams supporting them.

Insertion of Peritoneal Dialysis Catheter

Purpose: To surgically place a catheter into the peritoneal cavity, allowing for the instillation and drainage of dialysate fluid to remove waste products and excess fluid from the body.

Indications: End-stage renal disease (ESRD) where peritoneal dialysis (PD) is the chosen modality, acute kidney injury requiring dialysis when hemodialysis access is unavailable or contraindicated.

Key Steps:

1. Pre-procedure Preparation:
   • Patient assessment: Confirm indications, assess overall health, review imaging (if necessary, e.g., looking for adhesions).
   • Patient education: Explain the procedure, expected outcomes, post-operative care, and the principles of PD.
   • Bowel preparation: May be required depending on institutional protocol to reduce infection risk.
   • Antibiotic prophylaxis: Administered intravenously shortly before incision.
   • Site selection: Typically in the infraumbilical region, away from scars, stomas, or skin folds. The exit site is usually tunneled laterally and downwards.
2. Anesthesia:
   • Can be performed under local anesthesia with sedation, regional anesthesia (e.g., spinal), or general anesthesia, depending on patient factors and surgeon preference.
3. Incision and Peritoneal Entry:
   • A small incision (typically 2-4 cm) is made at the planned entry site, often just below the umbilicus.
   • The anterior rectus sheath is identified and incised.
   • The underlying rectus muscle is either split or retracted.
   • The posterior rectus sheath and peritoneum are carefully identified. Peritoneal entry can be achieved via:
     • Open Technique: A small incision is made directly into the peritoneum under direct vision.
     • Laparoscopic Technique: Ports are inserted, and the peritoneum is entered under laparoscopic visualization, allowing for adhesiolysis if needed and precise catheter placement.
     • Percutaneous Technique: A trocar is inserted blindly or with imaging guidance through the abdominal wall into the peritoneum. Less common in many centers due to higher complication rates compared to open or laparoscopic methods.
4. Catheter Tunneling:
   • A subcutaneous tunnel is created from the peritoneal entry site to the planned exit site. This tunnel helps anchor the catheter and provides a barrier against bacterial migration. A tunneling device is typically used.
   • The catheter is pulled through this tunnel, ensuring the deeper cuff(s) remain outside the peritoneum and the superficial cuff is within the tunnel, a few centimeters from the exit site.
5. Catheter Insertion into Peritoneal Cavity:
   • The tip of the catheter is carefully guided into the peritoneal cavity through the incision in the peritoneum.
   • The catheter is advanced downwards into the pelvic sump, which is the lowest point of the peritoneal cavity, facilitating fluid drainage.
   • Some surgeons perform an initial “flush” by infusing a small amount of sterile fluid (e.g., saline or dialysate) into the catheter to confirm flow and check for leaks around the entry site.
6. Securing the Catheter and Closure:
   • The peritoneum and posterior rectus sheath are closed snugly around the catheter using sutures to prevent leakage.
   • The anterior rectus sheath is closed.
   • The skin incision is closed. The catheter exit site is secured but left exposed to the air or covered with a sterile dressing, without closure.
7. Post-procedure Care:
   • Monitor for leakage from the exit site or incision.
   • Initial catheter care includes keeping the exit site clean and dry.
   • A “break-in” period (typically 1-2 weeks) is often recommended before regular PD cycles begin, during which minimal volume exchanges or automated cycler exchanges may be used.

Key Considerations: Proper site selection, meticulous sterile technique to prevent peritonitis, adequate anchoring and tunneling, and careful closure around the catheter to prevent leaks are critical for long-term success and minimizing complications.

Creation of Arteriovenous (AV) Fistula

Purpose: To surgically connect an artery directly to a vein, typically in the arm, to create a high-flow, durable vascular access site suitable for repeated needle cannulation required for hemodialysis.

Indications: End-stage renal disease (ESRD) requiring long-term hemodialysis. An AV fistula is the preferred access type due to lower complication rates (infection, thrombosis) compared to grafts or central venous catheters.

Key Steps:

1. Pre-procedure Assessment and Planning:
   • Detailed history and physical examination, assessing pulses and existing vascular issues.
   • Vascular mapping: Ultrasound evaluation of the arteries and veins in the potential access limb(s) to assess vessel size, patency, and suitability for anastomosis. This is a critical step to plan the specific veins and arteries to be connected (e.g., radiocephalic, brachiocephalic, brachiobasilic transposition).
   • Site selection: Distal sites (e.g., wrist) are preferred initially to preserve more proximal vessels for future access if needed. Non-dominant arm is generally preferred.
2. Anesthesia:
   • Usually performed under local anesthesia with sedation. Regional block (e.g., axillary block) or general anesthesia may be used depending on complexity, patient preference, or surgeon’s choice.
3. Incision(s):
   • An incision is made over the chosen artery and vein. This may be a single incision or separate incisions.
4. Vessel Identification and Dissection:
   • The chosen artery and vein are carefully identified and dissected free from surrounding tissues.
   • Tributaries of the vein are ligated to prevent blood flow away from the planned anastomosis.
5. Vessel Preparation:
   • The artery is typically mobilized, and temporary clamps are placed to control blood flow.
   • An incision (arteriotomy) is made in the artery.
   • The vein is mobilized, and temporary clamps are placed.
   • The end of the vein is prepared (spatulated) or an incision (venotomy) is made in the side of the vein, depending on whether an end-to-side or side-to-side anastomosis technique is chosen.
6. Anastomosis Creation:
   • The artery and vein are surgically joined using fine sutures. The goal is to create a wide, patent connection (anastomosis) allowing arterial pressure and flow into the vein.
   • The anastomosis is usually performed using a non-absorbable suture material.
7. Flow Check:
   • Once the anastomosis is complete, temporary clamps are released.
   • The surgeon confirms successful flow by observing dilation of the vein and palpating a thrill (vibration) and auscultating a bruit (listening using a stethoscope for a swishing sound) over the anastomosis and developing fistula.
8. Closure:
   • The incision(s) are closed in layers, typically using absorbable sutures in the subcutaneous tissue and skin sutures or staples.
9. Post-procedure Care:
   • Monitor the limb for swelling, pain, and signs of complications (e.g., hematoma).
   • Crucially, assess for the presence of a palpable thrill and audible bruit multiple times daily to confirm patency. Absence of thrill/bruit suggests thrombosis.
   • Patients are instructed to avoid pressure on the access arm.
   • “Maturation” is required: The vein needs time (typically 6-12 weeks) to dilate and thicken under arterial pressure and flow before it can be safely and effectively cannulated for hemodialysis. Exercises (e.g., squeezing a ball) may be recommended to aid maturation.

Key Considerations: Careful pre-operative mapping is essential. Surgical technique must minimize trauma to the vessels and create a wide, tension-free anastomosis. Maturation failure (the fistula doesn’t develop adequately) is a common problem requiring intervention or creation of a new access.

Multiorgan Deceased Donor Organ Retrieval (Kidney, Liver, and Pancreas)

Purpose: To surgically remove viable organs (in this case, kidneys, liver, and pancreas) from a deceased donor under sterile conditions to be transplanted into recipients.

Indications: A deceased person who meets the criteria for brain death (DBD) or circulatory death (DCD) and whose family has consented to organ donation. Organs must be assessed as suitable for transplantation.

Key Steps:

1. Pre-retrieval Preparation:
   • Donor management: Maintaining hemodynamic stability, oxygenation, and electrolyte balance.
   • Reviewing donor history, serology, and imaging.
   • Coordination: Logistics between the retrieval team, organ procurement organization (OPO), and potential recipient transplant centers.
   • Crossmatching: Final checks for compatibility between donor and potential recipients.
   • Sterile setup: Operating room prepared with sterile instruments and drapes.
2. Incision and Exposure:
   • A large midline incision is made from the sternal notch to the pubis to expose the abdominal and lower chest cavities.
   • The abdominal organs are carefully inspected in situ for gross pathology or damage that would render them unsuitable for transplant.
3. Systemic Heparinization:
   • Heparin is administered intravenously to the donor just before cross-clamping the aorta. This prevents clotting during the perfusion phase.
4. Mobilization and Dissection:
   • The organs destined for retrieval are systematically mobilized. This requires meticulous dissection to isolate the key vascular structures and ducts feeding/draining these organs (e.g., aorta, vena cava, hepatic artery, portal vein, bile duct for liver; renal arteries/veins for kidneys; splenic artery, superior mesenteric artery, portal vein, pancreatic duct for pancreas). The goal is to prepare the vessels for efficient flushing.
5. In-situ Perfusion (Cold Flush):
   • This is a critical step. The aorta is cross-clamped just above the diaphragm and distally (e.g., at the aortic bifurcation).
   • Large bore catheters are inserted into the aorta (typically in the infrarenal section) and sometimes the portal vein.
   • Large volumes of cold (4-8°C) organ preservation solution are rapidly infused through these catheters (aortic flush perfuses kidneys, liver, pancreas; portal flush primarily perfuses the liver and pancreas). The cold temperature and the solution’s chemical composition cool the organs and reduce their metabolic rate, minimizing ischemic damage.
   • As the cold solution is infused, the vena cava is opened (e.g., infra-diaphragmatic incision) to allow blood and flush solution to drain, decompressing the venous system and facilitating rapid cooling.
6. En Bloc Removal and Back-Table Preparation:
   • After adequate flushing (indicated by pallor of the organs and clear venous effluent), the organs are surgically removed en bloc (as a unit or connected block) to preserve vascular and ductal anatomy. For kidney, liver, and pancreas retrieval, this often involves removing the distal aorta, inferior vena cava, liver, pancreas-duodenum block, and kidneys together or in closely related units.
   • The entire block is placed in a basin of cold preservation solution or on sterile ice.
   • Back-table Preparation: Outside the donor’s body, on a sterile back-table, the block is carefully dissected further.
     • The liver is separated, preserving the common hepatic artery (often with an aortic patch), portal vein, and bile duct.
     • The pancreas is separated from the duodenum (if not transplanted en bloc with the duodenum), preserving the splenic and superior mesenteric arteries (often on an aortic patch) and the portal vein confluence.
     • The kidneys are dissected, preserving the renal artery (often with an aortic patch or Carrel patch) and renal vein. Excess fat and connective tissue are removed.
7. Packaging and Transport:
   • Each organ is carefully packaged in multiple sterile bags, immersed in cold preservation solution or packed with sterile ice, and placed in a cooler for transport to the recipient transplant centers. Strict labeling and documentation are essential.

Key Considerations: Timing is crucial to minimize warm and cold ischemia times. Meticulous dissection to preserve delicate vascular anatomy is vital. Collaboration between multiple surgical teams (often one for abdominal organs, one for thoracic) and the OPO is paramount.

Kidney Transplant

Purpose: To surgically implant a healthy kidney from a deceased or living donor into a recipient with end-stage renal disease.

Indications: End-stage renal disease (ESRD) caused by various conditions (e.g., diabetes, hypertension, glomerular nephritis), unresponsive to other treatments.

Key Steps:

1. Pre-transplant Preparation:
   • Recipient assessment: Final checks for stability, latest crossmatch results confirmed, and immunosuppression protocol initiated (usually starting pre-operatively).
   • Donor kidney assessment: Inspection of the retrieved kidney on the back-table, review of donor information, ensuring adequate preservation. Multiple arteries or veins need careful planning for reconstruction.
   • Sterile setup: Operating room prepared.
2. Anesthesia:
   • General anesthesia is typically used.
3. Incision and Exposure:
   • A curvilinear incision is usually made in the lower abdomen, typically in the right or left iliac fossa. The side chosen depends on factors like previous surgery, suitability of recipient vessels, or predicted ease of ureter placement.
   • The abdominal wall layers are divided.
   • The retroperitoneal space is entered, and the peritoneum is carefully dissected and retracted to the contralateral side to expose the iliac vessels.
4. Recipient Vessel Preparation:
   • The external iliac artery and vein are identified and carefully dissected free from surrounding structures.
   • Lymphatic vessels in the area are often ligated to prevent lymph collections (lymphocele) post-operatively.
   • Temporary vascular clamps are placed on the external iliac artery and vein to control blood flow.
   • An arteriotomy (opening) is made in the external iliac artery.
   • A venotomy (opening) is made in the external iliac vein.
5. Vascular Anastomoses:
   • This is a critical phase requiring precise surgical technique.
   • Venous Anastomosis: The donor renal vein is anastomosed (surgically joined) to the recipient external iliac vein using fine sutures. This is often performed first to establish venous drainage.
   • Arterial Anastomosis: The donor renal artery (often with its accompanying aortic patch from the donor retrieval, known as a Carrel patch) is anastomosed to the recipient external iliac artery. If there are multiple donor arteries, they may require reconstruction on the back-table or separate anastomoses.
   • Once the anastomoses are complete, the clamps are carefully released to restore blood flow to the transplanted kidney. The kidney should typically become pink and firm, and urine production may begin almost immediately.
6. Ureteral Anastomosis (Ureteroneocystostomy):
   • The donor ureter (the tube draining urine from the kidney) is anastomosed to the recipient’s bladder.
   • A tunnel is usually created within the bladder wall (extravesical or intravesical approach, such as the Lich-Gregoir technique) to help prevent urine reflux.
   • A surgical opening is made in the bladder, and the tip of the donor ureter is sewn into place.
   • A temporary stent (flexible tube) may be placed within the ureter and into the bladder to aid healing and prevent stricture (narrowing); it is typically removed later.
7. Closure:
   • The incision is closed in layers. A surgical drain may be placed near the kidney to remove any fluid collection (seroma, hematoma, or lymphocele); it is removed when drainage is minimal.
8. Post-transplant Care:
   • Intensive monitoring of kidney function (urine output, serum creatinine/BUN).
   • Aggressive immunosuppression to prevent rejection.
   • Monitoring for complications such as vascular thrombosis, ureteral leak or obstruction, infection, hematoma, or lymphocele.
   • Fluid and electrolyte management.

Key Considerations: Meticulous surgical technique, minimizing warm and cold ischemia times, careful management of the recipient’s fluid status, and effective immunosuppression are critical for successful graft function and patient survival. The complexity increases with multiple donor arteries or veins.

Conclusion

The procedures outlined above – the insertion of peritoneal dialysis catheters and creation of AV fistulas for pre-transplant management, the highly coordinated and time-sensitive process of multiorgan retrieval, and the challenging yet life-giving act of kidney transplantation – represent fundamental index procedures within the realm of transplant surgery. Each requires specialized knowledge, precise surgical skill, and a deep understanding of anatomy, physiology, and potential complications. While this guide provides a step-by-step overview, true mastery of these procedures is acquired through extensive training, mentorship, and clinical experience, forming the essential foundation upon which the success of organ transplantation is built. They serve as critical milestones in the journey from end-stage organ disease to restored health and quality of life for transplant recipients.