Obesity is a growing problem and has become increasingly common worldwide in recent years. It is a risk factor for diverse pathologies, including cardiovascular pathology, urinary tract lithiasis, and end-stage renal disease. The later is due to an increase in filtration fraction and glomerular filtration rate, which are predictors of renal function loss [2, 9]. Therefore, it is imperative to carefully evaluate these patients regarding their baseline cardiovascular risk as well as their increased risk of long-term kidney disease.

Obesity is also a significant risk factor of complications after abdominal surgery. Heimbach et al. studied 10 of 21 donors with a BMI greater than or equal to 35 and found that these donors had a greater number of minor perioperative complications and longer surgery times than nonobese donors. However, the occurrence of major complications and length of hospital stay were similar between the two groups [10].

The rate of conversion from laparoscopic to open surgery during hand-assisted laparoscopic donor nephrectomy (HALDN) has been shown to be the same for obese and nonobese donors, whereas laparoscopic donor nephrectomy conversion was found to be greater in obese donors [11]. A retrospective study of 5,304 donors showed no difference in mortality, readmission, and rates of repeat surgery between obese and nonobese donors [12].

Donors with a history of previous surgery have shown a higher rate of intra-abdominal adhesions than those without, with a rate of 85% (55–100%) in those with prior surgery compared with a rate of 52% (2–93%) in donors without prior surgery [13–15]. This has no negative effects on the probability of surgical success and is not a contraindication to a minimally invasive approach.

Intra-abdominal adhesions lead to an increased risk of conversion to open surgery and subsequent increased risk of patient morbidity. Kok et al. demonstrated this in a study of 161 patients; a higher number of conversions were recorded in patients with adhesions (0% in donors free of adhesions vs. 10% in donors with intra-abdominal adhesions, p = 0.005) [16].

Smoking not only increases the risk of developing cancer but has also been shown to particularly increase the risk of developing kidney cancer by a factor of 1.8 [17]; this is a significant consequence for a live donor patient. Smoking also affects the quality of healing: nonsmokers produce 1.8 times more collagen than smokers. This leads to a higher rate of dehiscence, surgical site infections, incisional hernia, and injury among patients who smoke [18–20].

Kidney donors who are older than 60–70 years present with a higher incidence of concomitant diseases and decreased kidney function for their age. This makes them more susceptible to surgical complications.

Despite these factors, and because of the scarcity of living donors, the selection criteria are becoming increasingly flexible, and older donors are seen more frequently. Several studies have shown that when selecting donor grafts with similar rates of survival, no differences in complication rates are observed, regardless of donor age [21, 22].

Elderly donors must be rigorously assessed before kidney donation because of their lower glomerular filtration rate and higher risk of developing long-term hypertension [23].

Studies suggest that normotensive kidney donors are at an increased risk of developing hypertension. Boudville et al. reported an increase of 5 mmHg in systolic blood pressure in the 5–10 years after a nephrectomy. Systolic blood pressure increase is presumed to be a result of normal aging [23].

These findings, which have also been reported by M. Cherif et al. in a retrospective study of patients including 321 LDN, provide evidence that the increase in blood pressure may be greater and the rise in blood pressure may increase over time. At the 10-year mark, systolic blood pressure was shown to have increased by 13.6 mmHg and diastolic blood pressure by 5.4 mmHg. Being 60 years or older and having a preoperative TFG were both found to be associated with increased pressure or arterial hypertension at follow-up [7]. According to S.A. et al., the most frequent complication of kidney donation was hypertension, occurring in 37.5% of patients; the cohort in their study comprised 21 men and 11 women. Stratification of the hypertension cases resulted in the following distribution: moderate hypertension in three patients with an average of 160/98 mmHg and minimal hypertension in 29 patients with an average of 145/95 mmHg. Of the 32 patients, 16 had a family history of high blood pressure. All of the participants had a normal blood pressure prior to the procedure [4]. However, researchers in other studies have not found this hypertensive effect [24].

Potential hypertensive donors should have their blood pressure under control at the time of surgery and be without related target organ damage. The risk of kidney disease developing in this group is expected to be less than 1 in 100 [25].

People with impaired glucose tolerance have a higher risk of developing type 2 diabetes; those with a family history of diabetes mellitus have up to a 30% risk of developing type 2 diabetes and those with no family history have up to a 10% risk [26].

Okamoto et al. studied 444 living donors with a mean follow-up of 7 years and found no difference in the development of diabetes mellitus, renal disease, or mortality among donors with glucose intolerance and impaired glucose tolerance [27].

It is considered a contraindication to donate a kidney to a recipient with diabetes mellitus because of a 25–51% risk of the recipient developing long-term diabetic nephropathy [28].

Potential donors with glucose intolerance or a family history of diabetes mellitus must be advised about a possible increase in the risk of developing diabetes mellitus and consequent nephropathy.

Initial studies reported that there was no difference in the occurrence of pregnancy complications between kidney donors and the general population [29, 30].

However, more recent studies have found higher risks associated with pregnancy following donor nephrectomy. A study of 326 women, with a total of 726 pregnancies and 106 pregnancies post-donation, reported an increase in the incidence of preeclampsia following nephrectomy; the incidence was 5.7% in donors and 2.6% in non-donors, p = 0.03. However, the rate of preeclampsia in the nephrectomy group was still within the range observed in the normal population. The rate of pregnancies with stillborn infants increased from 1.1% in the control subjects to 2.8% after donor nephrectomy (p = 0.17) [31].

Ibrahim et al. found that pregnancy after kidney donation was significantly less likely to result in delivery at term (73.7% vs. 84.6%, p < 0.001) and more likely to result in fetal loss compared to complications during pregnancy in non-donors (19.2% vs. 11.3%, p < 0.001). Pregnancy after kidney donation was also associated with an increased risk of gestational diabetes, gestational hypertension, proteinuria, and preeclampsia [32].

In 12–33% of kidney donors, multiple renal arteries are present, and in 5–10%, multiple renal veins are found [33, 34]. Multiple vasculature of a donor kidney can cause an increase in the risk of complications in recipients, such as delayed graft function [35, 36].

Risks of vascular complications, hypertension, proteinuria, and Glomerular Filtration Rate (GFR) increase with multiple vessels vs. a single vessel have not been found in recent studies [37, 38].

There is ongoing debate about whether donating a left or right kidney is the best option, given the small differences in the anatomy of each. The right kidney is easier to surgically remove, and right nephrectomy decreases the risk of laceration of the spleen; however, right nephrectomy is also associated with a shorter renal vein and an increased risk of thrombosis [39].

Left donor nephrectomy, on the other hand, is advantageous during surgery because the renal vein is long; however, the left kidney is also more difficult to recover. The anatomic location and the proximity to the cisterna chyli cause an increased risk of chylous leak; this risk is nearly 4% and is exclusively related to nephrectomy of the left side [40].

There is no documented difference in length of hospital stay, quality of life, rate of recipient complications, or survival of the graft in right- or left-sided kidney donation; there has been, however, a reported difference in speed of recovery, with the right side being faster than the left [41].

In summary, researchers agree that right-sided kidney donation is preferable because of the faster recovery period and ease of surgical removal [2].

Laparoscopic complications are frequent. A prospective study of the Norwegian donor registry and hospital records from the United States identified a range of 6.3% for major complications and of 18–22% for minor complications [44]. The reported complication rates varied; the United States reported a rate between 2.8% and 6.8% for perioperative complications and between 10.3% and 17.1% for postoperative complications.

The probability of presenting perioperative complications increased by 1% for each 1-year increase in donor age (OR = 1.01, p < 0.0001). Women were 14% less likely to experience any complication perioperatively after donation (OR = 0.86, p = 0.001). Obese donors were 55% more likely to experience the most serious perioperative complications. Genitourinary, hematological, and psychiatric pathologies have all been associated with an increased risk of perioperative complications and are the most serious complications (Clavien ≥3) [43].

One study estimated the mortality rate to be between 0.02% and 0.03%, with pulmonary embolism being the most frequent cause [4]. Risk factors associated with mortality include male sex, African ethnicity, and high blood pressure [8]. The greatest risks associated with live donor nephrectomy are perioperative morbidity and mortality.

The first step in laparoscopic surgery is to establish access to the pneumoperitoneum. This is the most critical and challenging phase, during which more than 50% of the total laparoscopic complications occur. Mortality rates range from 0.05% to 0.2%, according to published studies [45, 46]. Complications related to access, including vascular injury, retroperitoneal and intestinal perforation, hernia, wound infection, hematoma, and abdominal wall metastasis of the trocar site, are uncommon but can result in significant morbidity and even death [47]. Vascular injury, defined as a lesion of the large vessels, is the most serious complication and occurs most frequently when entering the abdominal cavity [48, 49]. Although the incidence of vascular injury in laparoscopic procedures is as low as 0.05–0.26%, it can cause severe morbidity and death in 8–17% of patients [50, 51]. Researchers believe that the true incidence is greater than this rate suggests [52, 53].

Various technologies and techniques for laparoscopic access have been introduced to reduce complications. The closed techniques using a Veress needle, open Hasson technique, and low vision direct input method have all been used. Although there have been several reports on major vascular injury occurring during the closed input technique, no consensus on the methodological superiority of a technique has been reached due to insufficient evidence. Based on previous studies [54, 55], the Veress needle is the most popular method used by gynecologists; however, novice surgeons prefer the open technique [48].

Vascular complications are reported to be the main complications to occur from the beginning of surgery to after the surgery has been completed. They have been reported in 0.03–2.7% [56] of intraoperative complications and may account for as much as 40% of all complications in laparoscopic surgery [57].

Major vascular injury, is the most serious and dreaded complication and occurs most frequently during entrance into the abdominal cavity [48, 49]. Although the incidence of vascular injury in laparoscopic procedures is relatively low, it can cause severe morbidity and death in 8–17% of patients as described above [50, 51]. However, the true incidence is believed to be underestimated by this rate as previously stated [52, 53]. As described above, various technologies and techniques for laparoscopic access, including the closed technique with Veress needle, open Hasson technique, and entry under direct vision method, have been introduced to reduce the occurrence of complications. Although there have been several reports on major vascular injury during the closed technique, there is still no consensus as to the superiority of one method over the others [54, 55].

Additional procedures that can cause vascular complications are radical prostatectomy and either partial or simple radical nephrectomy [57].

One study has determined that the mortality rate of donor kidneys 90 days after surgery is 0.03%, with ensuring the patency of both the renal artery and renal vein being one of the most challenging tasks [58]. Vascular control can be achieved through either non-transfixion or transfixion techniques. Techniques of non-transfixion ensure closure by suturing simple loops or clips around the vessels but not through them. Transfixion techniques, on the other hand, bind the suture material through the wall of the vessel, thereby ensuring that the staple or suture material penetrates the artery or vein [59].

In 2006, a survey by the American Society of Transplant Surgeons revealed a significant number of fatal bleeding events in live donor nephrectomies (LDN) related to the inadequacy of certain clips. This discovery led to the contraindication of the Weck® Hem-o-lok® clip for control of the renal artery during LDN [58].

Simforosh et al. conducted a study on renal artery placement of Hem-o-lok clips that were both 10 mm and 12 mm larger than titan clips; they found no evidence of bleeding or mobilization of the Hem-o-lok. Consequently, this was then considered a safe surgical technique [8].

This result led to the wide use of the stapler system, which despite being better and more widely used still has the potential for failure. Failure is defined as instant device malfunction with the inability to meet performance expectations. This excludes issues such as clip size or clip length, patient bleeding, vascular leakage, and tissue thickness. There are few publications that reflect the failure of staplers in urology [60, 61].