Donor Nephrectomy

Since 1988, over 517,246 kidney transplants have been performed in the United States. During 2021, a record number of kidney transplants were performed in the US, including 24,669 kidney-alone and 820 kidney plus at least one additional organ. Of those transplants, 5970 were identified as originating from living-donors (24.2%) and 19,519 (76.5%) from deceased-donors. ^[1] In 2019, more than 244,000 patients were alive and with a functioning transplanted kidney; currently, more than 100,000 adult patients are waiting for kidney transplants. ^[2]

Donor nephrectomy is done via either a laparoscopic or an open surgical approach. This article describes the 2 most common approaches: transperitoneal laparoscopic donor nephrectomy (LDN) and microinvasive open donor nephrectomy (MDN). Laparoscopic surgery takes longer than open nephrectomy but provides a more rapid recovery for the donor. The vast majority of living-donor nephrectomies are now performed laparoscopically, with donors discharged from the hospital about 48 hours following the surgery. The left kidney is preferred for living-donor nephrectomy because the renal vein is longer on the left. However, when vascular, urological or other abnormalities are present, the right kidney may be procured. ^[3]

LDN can be transperitoneal or retroperitoneal  and the kidney is usually removed by enlarging the umbilical port incision. MDN, an open approach to donor nephrectomy, is commonly performed through a small flank incision, without rib resection. 

The subsequent advance in LDN was the laparoendoscopic single-site (LESS) procedure. In this operation, a single access port (eg, GelPOINT) is inserted into the abdomen through a 5-cm incision, and the laparoscopic instruments are triangulated through the gel-covered port. More recent techniques use a 2-port or mini-laparoscopic approach. ^{[4, 5, 6]}   The feasibility of the LESS procedure may be limited by the patient's body habitus (eg, high body mass index or previous abdominal surgical procedures), the ability of the surgeon to triangulate the instruments effectively, and the presence of multiple renal arteries. Thus, the 2-port laparoscopic procedure allows better triangulation while maintaining cosmesis without differences in perioperative patient outcomes.

Kidney Disease: Improving Global Outcomes (KDIGO) clinical guidelines (2019) recommend “mini-open” laparoscopy or hand-assisted laparoscopy by trained surgeons as the optimal approaches for living-donor nephrectomy.  In select circumstances, such as donors with extensive previous surgery or adhesions, and at centers where laparoscopy is not routinely performed, open nephrectomy (flank or laparotomy) may be acceptable. Robotic, single-port, and natural orifice transluminal nephrectomy are not recommended for donor nephrectomy. ^[3]   

However, in 2021 Garden and colleagues reported successful robotic single-port donor nephrectomy in a seriers of 7 patients using the da Vinci SP® Surgical System, with no Clavien-Dindo grade ≥ III complications within 90 days. Pain scores at 48 hours postoperatively averaged 1.7/10. The da Vinci SP® Surgical System is approved for use in urologic procedures and uses a single, 25 mm multichannel trocar containing a high-definition, 3D robotic camera, and three instrument slots that deploy intracorporeally. ^[7]

Transvaginal nephrectomy has also been attempted but has not gained widespread acceptance. A few studies have evaluated LDN with vaginal extraction. Incisions made through the natural orifice of the vagina are thought to yield better cosmesis and less postoperative pain. An endoscopic specimen retrieval bag (eg, EndoCatch) is used to retrieve the kidney, and an episiotomy is made to facilitate this removal. ^[8]  The main points of debate concerning this procedure have to do with the infectious complications of transvaginal removal, the issues involved in removing large kidneys, and the use of nulliparous donors.

Additional information can be obtained from the following sources:

• UNOS
• Organ Procurement and Transplantation Network (OPTN)
• Living Organ Donor Network (LODN)
• US Department of Health and Human Services:  Organ Donation Information
• Scientific Registry of Transplant Recipients (SRTR)

Donor Criteria

Any individual who is considered a suitable living kidney donor candidate may undergo a donor nephrectomy. The donor may be either related to the potential recipient or unrelated (eg, a spouse, friend, or coworker). An altruistic donor is a person who wishes to donate a kidney to a stranger. A number of kidney-paired donation (KPD) programs match incompatible donor-recipient pairs, so that the donor of one pair donates to the recipient of the other pair and vice versa. Kidney donation chains involving multiple donor-recipient pairs have also been set up. The counts of KPD transplants in the Unitied States have increased sharply from 27 in 2005 to 642 in 2016, though they appear to have plateaued and now represent about 10% of all living-donor transplantations. ^[9]

The fundamental philosophy of living kidney donation derives from the Hippocratic oath: “First, do no harm.” Contraindications to kidney donation may be medical, psychological, social, immunologic, anatomic, or ethical.

Medical contraindications include the following:

• Age - There is no absolute upper age limit; however, donors must be at least 18 years old
• Hypertension - Blood pressure higher than 140/90 mm Hg or the use of antihypertensive medications
• Obesity - Body mass index (BMI) greater than 30-35 kg/m ²
• Diabetes mellitus or an abnormal glucose tolerance test, a history of gestational diabetes, or a strong family history of diabetes (especially in a first-degree relative)
• Malignancy
• Microalbuminuria or overt proteinuria
• Recurrent kidney stone disease
• Any kidney disease
• Low creatinine clearance (glomerular filtration rate < 70-80 mL/min)
• Any transmissible infection (eg,  HIV infection,  hepatitis B, or  hepatitis C)
• Any other significant comorbidity (eg, cardiac, pulmonary, or autoimmune disease)
• Chronic pain issues and dependence on medications that could negatively affect kidney function (eg, nonsteroidal anti-inflammatory drugs [NSAIDs]) - This is a relative contraindication
• Smoking - This is a relative contraindication
• Active substance abuse

Persistent microscopic hematuria, in the absence of fever, trauma, menstruation or vigorous exercise, must be appropriately worked up but is not considered a contraindication for living donor nephrectomy. ^[10]

Psychological and social contraindications include the following:

• An active psychological condition, such as anxiety/ depression or psychosis - If necessary, donors should undergo a psychological assessment as a part of their evaluation
• Social barriers to donation - All donors should undergo a social assessment to ensure that no such barriers exist

Immunologic contraindications include the following:

• Incompatibility with the recipient - Some centers, however, perform transplants across different blood groups and positive cross-match pairs; in such situations, using KPD and donation chains has enabled more donations

Anatomic contraindications include the following:

• The presence of a solitary kidney or a horseshoe-shaped kidney ( Horseshoe Kidney Imaging) - This is an absolute contraindication
• The presence of 3 or more renal arteries

Ethical contraindications include the following:

• Financial compensation for organ donation - Any such compensation is prohibited; in the United States,  the National Organ Transplant Act (NOTA) of 1984 states that "[i]t shall be unlawful for any person to knowingly acquire, receive, or otherwise transfer any human organ for valuable consideration for use in human transplantation"
• Coercion - During the evaluation phase, it is essential to ensure that the donor has not been coerced

Donor Education/Informed Consent

To make an independent and voluntary decision, the donor must be fully informed and mentally competent. The donor must sign a consent form acknowledging that the following information was disclosed:

• Reasonable alternatives to the proposed therapy
• The risks and benefits of the procedure
• The outcomes for the proposed organ transplant at a particular center and in the United States

The American Society of Transplantation (AST) Live Donor Community of Practice (LDCoP) has released  a consensus statement for best practices in live kidney donation. The statement noted that educational practices for living donors remain insufficient to ensure enough understanding to optimize informed consent, despite strengthened OPTN/UNOS policy and initial implementation of an independent living donor advocate.Key recommendations for improving donor education and informed consent include the following  ^[11] :

• Hire dedicated living donor personnel, including a living donor coordinator and dedicated physician champion or director
• Education approaches shown effective in other fields of practice should be considered, including incorporation of health literacy best practices, adult learning theories, and the use of peer mentors, navigators, and family ambassadors.
• Educational strategies should include guidance on interpretation of risk information as well as assessment of risk comprehension.
• OPTN policy regarding required disclosures during the informed consent process should be expanded to include education about the evolving understanding of the risk of ESRD in living donors compared with healthy non-donors.

The AST-LDCoP recommends the following additional elements be included in the process of informed consent ^[11] :

• Possible complications of pregnancy
• Factors influencing recipient benefits from live-donor kidney transplantation
• Potential psychosocial benefits from donating and psychosocial risks from not donating
• Factors that most strongly influence medical and psychosocial risk variability

Donor evaluation

In addition to a detailed history and physical examination, a thorough investigation is performed for each potential donor. Laboratory tests include a complete blood count (CBC), a basic metabolic panel, and coagulation studies. Electrocardiography (ECG) and chest radiography are performed if indicated. A pregnancy test is obtained in women of child-bearing years. Generally, type and screen or type and cross-match for packed red blood cells are performed preoperatively in case the patient needs to be transfused intraoperatively or postoperatively.

An important part of the workup is the use of renal imaging studies to ensure that the potential donor retains 1 normal kidney after the nephrectomy, ^[12]  to evaluate the renal blood vessels, to provide guidance for planning a surgical approach to dissection and ligation, and to circumvent intraoperative complications. This is typically done with computed tomographic angiography (CTA) or magnetic resonance angiography (MRA).

Equipment

General surgical equipment relevant to both microinvasive donor nephrectomy (MDN) and laparoscopic donor nephrectomy (LDN) includes the following:

• A general and vascular surgical tray with scissors, forceps, needle holders, retractors, scalpels, clamps, and sutures (according to the surgeon's preference)
• Devices for suction, irrigation, insufflation, and electrocautery (these must be tested and functional)
• Agents for intraoperative hemostasis (eg, fibrinogen or thrombin products)
• An ice bath or some other preservation method (according to the surgeon's preference)

For MDN, deaver retractors are employed to expose the retroperitoneal space. Surgical clips for securing hemostasis are associated with an increased risk of hemorrhage and therefore should not be used. Either sutures or vascular staplers are suitable for vessel ligation.

For LDN, a Veress needle or a Hasson cannula can be used to achieve entry into the peritoneum for insufflation and trocar insertion. The procedure requires a pair of 10-mm trocars and a single 5-mm trocar. A camera with a 30º lens is needed for visualization; it should have a light source and should be white-balanced. A 15 mm endoscopic specimen bag will facilitate retrieval of the kidney.

Procedure timing

Organ procurement is time sensitive and the transplant surgical team should minimize the warm and cold ischemic times.  Recommended procurement time limits for optimal organ viability are depicted in tabular form in the image below. ^[13]

Acceptable Warm and Cold Ischemia Times for Renal Allografts

Patient Preparation

Patient preparation includes consideration of anesthetic requirements and patient positioning.

In general, the donor nephrectomy patient is without renal compromise. Therefore, the special renal precautions taken with a kidney transplant recipient are typically not necessary, and a more generalized anesthetic plan is usually followed. ^[14] The anesthesiologist and patient discuss the anesthetic plan, the risk and benefits of anesthesia, and any remaining questions before proceeding to the operating room (OR).

Anesthesia induction

In the OR, standard monitoring devices as specified by the American Society of Anesthesiologists (ASA)—including ECG, pulse oximetry, and blood pressure cuff—are placed on the patient, and the patient is preoxygenated with 100% oxygen. Depending on the patient's general condition and any comorbid conditions present, an arterial line might be placed before or after induction (initiation) of general anesthesia for closer blood pressure monitoring. A second large-bore intravenous (IV) catheter is also likely to be placed after induction.

Induction of general anesthesia is accomplished with an IV agent such as propofol or etomidate. A paralytic drug is also given at the time of induction so that endotracheal intubation can be established. Once patients are intubated, they are maintained on a ventilator until they are spontaneously breathing after the operation is complete.

Intraoperative patient management

A warming blanket (eg, Bair Hugger) is placed on the patient to maintain core body temperature. The patient is positioned carefully for optimal surgical exposure, and IV antibiotics are given before incision.

Maintenance of anesthesia is typically accomplished with an inhaled anesthetic agent (eg, sevoflurane, desflurane, or isoflurane). A narcotic (eg, fentanyl, hydromorphone, or morphine) is administered throughout the operation as needed for analgesia. A paralytic agent is given as needed to facilitate optimal surgical exposure.

IV hydration is critical for optimizing blood flow to the remaining kidney; accordingly, normal saline or lactated Ringer solution is administered to maintain adequate fluid status. Urine output is carefully monitored via a Foley catheter; such monitoring facilitates the administration of IV fluids.

The surgeon will probably request that other medications (eg, mannitol or heparin) be given to the patient just before the vessels to the kidney are clamped in preparation for removal of the kidney. He or she may also request that protamine be given after removal of the kidney to partially reverse the effect of the heparin.

Patient positioning

Patients should be carefully secured to the operating table, and a Foley catheter should be placed to decompress the bladder and reduce injury during trocar insertion.

Microinvasive donor nephrectomy

In preparation for MDN, the donor is placed in the lateral decubitus position with the ipsilateral side up. The operating table is in 30º flexion with a 20º Trendelenburg tilt. A vacuum-activated bean bag or foam padding is used to stabilize the patient and facilitate posterior rotation of the hips for optimal access. A pad is placed to maintain the neck in neutral position and prevent cervical-thoracic vertebral strain, and padding is used at the dependent axilla to prevent brachial plexus injury.

Laparoscopic donor nephrectomy

The patient is placed in a modified lateral decubitus position with the flank at a 45º angle to the table and the hips rotated posteriorly as described above. The dependent leg is flexed at 45º, and the upper leg is straight and level with the abdomen; foam padding is placed between them. The arms are maintained at chest level, and both are secured to the ipsilateral side of the table. The table may be flexed at 30º to facilitate port placement and is usually lowered after pneumoperitoneum is established. Padding is employed as described above.

Microinvasive Donor Nephrectomy

Microinvasive donor nephrectomy (MDN) is performed as follows (see the video below).

With the patient properly positioned and prepped, a 6-8 cm incision is made from the tip of the 10th rib to the edge of the rectus abdominis (see the image below). The rib is not resected. Instead, the fascia and muscle layers are split in the line of their fibers to minimize postoperative pain.

The peritoneum is retracted medially with Deaver retractors to expose the retroperitoneal space and the kidney. Dissection starts at the ureter, which is separated from the retroperitoneal tissues; the periureteric vessels must be preserved to maintain the blood supply to the ureter. The perinephric fascia (Gerota's fascia) is incised and the kidney mobilized.

The adrenal and gonadal veins are ligated or clipped with the endovascular stapler and divided. The renal vein is dissected to its junction with the inferior vena cava (IVC), and the renal artery is dissected to its origin from the aorta. The ureter is stapled and divided at the point where it crosses the iliac artery, then divided proximally.

The patient is given mannitol 25 g and heparin 5000 U intravenously (IV). Administering mannitol and furosemide before removing the kidney promotes free-radical scavenging and diuresis, respectively, thereby minimizing ischemia-reperfusion injury. ^[15]

The renal artery is divided with a vascular stapler. The authors use the Ethicon Proximate TX30V 30-mm reloadable vascular linear stapler, applying it across the renal vein close to the IVC. The kidney is immediately flushed on the back table in an ice basin with a preservative solution maintained at 4º C. Protamine 25 mg is administered to the donor to partially reverse the heparin effect.

Hemostasis is obtained, and the wound is closed in layers with a single continuous 2-0 monofilament suture at each muscle layer. A field block is placed using local and regional infiltration of bupivacaine 0.25% to reduce postoperative pain. This step shortens the hospital stay, with 85% of donors going home the next day. ^[16]

Laparoscopic Donor Nephrectomy

The left-sided approach to laparoscopic donor nephrectomy (LDN) avoids the need for liver retraction and often provides a longer renal artery and vein.

Laparoscopic left donor nephrectomy is performed as follows.

Pneumoperitoneum is established through either a closed technique with a Veress needle or an open technique with a Hasson cannula or hand port. ^[17] Insufflation of the peritoneum should be maintained at the lowest pressure feasible to enhance renal blood flow intraoperatively. Approximately 10 mm Hg is optimal, and pressures exceeding 15 mm Hg should be avoided. In an obese patient, higher pressures may be needed for insufflation, and an open approach may prove necessary instead.

The first 10-mm port is placed lateral to the rectus abdominis, approximately 1 in. medial and 1 in. superior to the anterior superior iliac spine. The second 10-mm port is placed at the umbilicus, and the final port is placed midway between the xiphoid and the umbilicus. (A right-sided approach necessitates the placement of an additional midaxillary 5-mm port for liver retraction.)

A camera is placed in the 10-mm umbilical port, a forceps in the 5-mm port, and a surgical scissors or hook electrode in the other 10-mm port. The lateral border of the peritoneum, including the colorenal ligaments, is bluntly dissected to allow the colon to be reflected medially from the splenic flexure to the sigmoid colon, exposing the perinephric fascia (Gerota's fascia). The fascia is incised to expose the superior pole of the kidney. Once mobilized, the superior pole can be elevated to facilitate further dissection of Gerota's fascia to expose the hilum.

The renal vein and artery are carefully dissected and divided, along with the gonadal, adrenal, and lumbar veins. The ureter is then dissected inferiorly and ligated at the point where it crosses the iliac artery and vein. The patient is given mannitol and heparin, as in MDN.

An endovascular stapler is used to transect first the renal artery and then the renal vein, thus freeing the kidney for removal. The stapler is most effective if it is compressed for 5-10 seconds before being discharged; this measure allows displacement of third-space fluid within the vasculature, reduces the distance that the staple must traverse, and provides greater security at the staple line.

A 15 mm endoscopic specimen retrieval bag is advanced through the umbilical port; once in place, it springs open to allow careful capture of the organ. The bag is then retracted to the abdominal wall, and the umbilical incision is enlarged by approximately 5 cm to facilitate atraumatic removal. The fascia is closed, pneumoperitoneum is reestablished, and hemostasis of the renal bed is secured before closure. Ports should be closed individually with 1-0 polydioxanone suture and inspected intra-abdominally for bleeding.

Postoperative Care

Postoperative pain is best controlled by means of a patient-controlled analgesia (PCA) device, the use of which is discontinued 12 hours after the procedure, along with the Foley catheter. Nonsteroidal anti-inflammatory drugs (NSAIDs) should be avoided during the perioperative period, and morphine or hydromorphone PCA can be followed with oral analgesics.

Perioperative mortality is reported to be 0.03% for all methods of donor nephrectomy. ^[18]  Mortality is higher in men, black donors, and donors with hypertension. The practice of nontransfixion techniques for arterial closure in the donor nephrectomy increases mortality risk due to clip dysfunction. Despite a US Food and Drug Administration (FDA) recall of these devices, use of these devices persists and deaths have been reported. ^[19]

With regard to overall mortality, among a cohort of live kidney donors compared with a healthy matched cohort, mortality was not significantly increased after a median of 6.3 years. ^[20]  There are no significant differences between laparoscopic and open techniques with respect to graft survival at 1 year, despite the increased WIT and longer operating times associated with laparoscopy. ^{[21, 22]}

Compared with MDN, LDN is associated with elevated creatinine levels for as long as 1 month after the procedure, increased utilization of immediate postoperative dialysis in the recipient, and a higher incidence of ureteral complications. ^[23]  MDN does not create a pneumoperitoneum and thus avoids many complications associated with LDN (eg, adhesions, small bowel obstruction, herniation, shoulder pain from incomplete CO₂ evacuation, and spleen, bowel, and vascular injury).

Overall, complication rates are 2-3 times higher with LDN than with open procedures; this difference may be attributable in part to the steeper learning curve associated with LDN. ^[24]  However, reported rates of postoperative pain have been much lower with the laparoscopic approach, and the time before return to work has been substantially shorter. ^[25]

A review of 14,964 live donor nephrectomies determined that overall, 16.8% of donors experienced a perioperative complication, but major Clavien ≥4 complications affected only 2.5%. ^[26]  The most common complications and their frequencies were as follows:

• Gastrointestinal (4.4%)
• Bleeding (3.0%)
• Respiratory (2.5%)
• Surgical/anesthesia-related injuries (2.4%)
• Other complications (6.6%)

Risk factors for complications included the following:

• African-American race
• Obesity
• Pre-donation hematologic or psychiatric conditions
• Robotic nephrectomy

Annual center volume of more than 50 nephrectomies was associated with lower risk. ^[26]

Living kidney donation is not associated with a significant progressive decline in renal function. ^{[27, 28]}  A retrospective review of 256 donors in Norway revealed that at 5 years after donation, there was no significant progressive decline in glomerular filtration rate (GFR) and no significant increase in proteinuria. Mean blood pressure was 122/76 mm Hg at donation, 124/78 mm Hg at 1-year follow-up, and 127/79 mm Hg at 5-year follow-up. ^[27]  

The risk of end-stage renal disease after kidney donation does not exceed ESRD rates in the general population. However, recent studies comparing to individuals selected for baseline good health suggest that donation is associated with an increase in the risk of ESRD, although the risk increase is small and the absolute postdonation risk remains low. ^[19] . Based on the donor registry for 96,217 donors and records for healthy participants in NHANES III, the cumulative incidence of ESRD at 15 years was estimated as 30.8 per 10,000 in donors compared with 3.9 per 10,000 in matched, healthy nondonors (risk attributable to donation of 26.9 per 10,000). ^[29]

 

A personalized postdonation care plan should be provided prior to donation with follow-up care recommendations, including monitoring for chronic kidney disease (CKD). Annual post-donation monitoring should include the following ^[3] :

• Blood pressure measurement
• Body mass index (BMI) measurement
• Serum creatinine measurement with calculation of estimated glomerular filtration rate (eGFR)
• Albuminuria measurement
• Review and promotion of a healthy lifestyle, including regular exercise, healthy diet, and abstinence from tobacco
• Review and support of psychosocial health and well-being