Anatomical variation of the posterior lumbar tributaries of the left renal vein in retroperitoneoscopic left living donor nephrectomy

The Incidence and Variants of the Reno-Hemiazygos Connection

Background/Objectives: Although common anomalies of the left renal vein (LRV) are pretty well documented in the literature, the drainage of the left renal blood via the hemiazygos vein lacks comprehensive support. We, therefore, aimed to study the incidence of the reno-hemiazygos connection (RHC). Methods: A total of 150 computed tomography scans (85 men and 65 women) were documented for the origin of an RHC from the LRV. Results: RHCs were found in 14/150 cases (9.34%). They were more prevalent in women (71.43%). In 11/14 cases, type 1 RHCs ascended directly along the postero-lateral left side of the aorta (direct hemiazygos flow). In 3/14 cases, type 2 RHCs (indirect hemiazygos flow) had a lumbar segment corresponding to the second lumbar vein and a pretransversary segment corresponding to an ascending lumbar vein. In 9/14 cases (64.29%), the RHC was connected to a typical LRV. In 1/14 cases (7.14%), the RHC was connected to the junction between the LRV and a left retropelvic tributary. In another case (7.14%), the RHC was connected to a retroaortic LRV and, in three cases (21.43%), to a circumaortic LRV. Triple left renal arteries were found in type 1 and, respectively, type 2 cases. The vertebral level of the inferior end of the RHC was variable, from the L1/L2 disc level to the L3 level. Conclusions: When present, the RHC serves to connect the superior and inferior caval systems. This may be physiologically of use or not, but surgically, it is a major anatomical risk factor for bleeding if its presence is not checked preoperatively.

Maternal posture-physiology interactions in human pregnancy: a narrative review

There are several well-known medical conditions in which posture and gravity interact with natural history, including pregnancy. In this review, we provide a comprehensive overview of interactions between maternal posture and maternal physiology and pathophysiology at rest during pregnancy. We conducted a systematic literature search of the MEDLINE database and identified 644 studies from 1991 through 2021, inclusive, that met our inclusion criteria. We present a narrative review of the resulting literature and highlight discrepancies, research gaps, and potential clinical implications. We organize the results by organ system and, commencing with the neurological system, proceed in our synthesis generally in the craniocaudal direction, concluding with the skin. The circulatory system warranted our greatest and closest consideration-literature concerning the dynamic interplay between physiology (heart rate, stroke volume, cardiac output, blood pressure, and systemic vascular resistance), pathophysiology (e.g., hypertension in pregnancy), and postural changes provide an intricate and fascinating example of the importance of the subject of this review. Other organ systems discussed include respiratory, renal, genitourinary, gastrointestinal, abdominal, and endocrine. In addition to summarizing the existing literature on maternal posture-physiology interactions, we also point out gaps and opportunities for further research and clinical developments in this area. Overall, our review provides both insight into and relevance of maternal posture-physiology interactions vis à vis healthcare's mission to improve health and wellness during pregnancy and beyond.

Anatomical Variants of the Renal Veins and Their Relationship with Morphofunctional Alterations of the Kidney: A Systematic Review and Meta-Analysis of Prevalence

Background: Variations in renal veins are quite common, and most people do not experience issues due to them. However, these variations are important for healthcare professionals, especially in surgical procedures and imaging studies, as precise knowledge of vascular anatomy is essential to avoid complications during medical interventions. The purpose of this study was to expose the frequency of anatomical variations in the renal vein (RV) and detail their relationship with the retroperitoneal and renal regions. Methods: A systematic search was conducted in the Medline, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS databases from their inception until January 2024. Two authors independently carried out the search, study selection, and data extraction and assessed methodological quality using a quality assurance tool for anatomical studies (AQUA). Ultimately, consolidated prevalence was estimated using a random effects model. Results: In total, 91 studies meeting the eligibility criteria were identified. This study included 91 investigations with a total of 46,664 subjects; the meta-analysis encompassed 64 studies. The overall prevalence of multiple renal veins was 5%, with a confidence interval (CI) of 4% to 5%. The prevalence of the renal vein trajectory was 5%, with a CI of 4% to 5%. The prevalence of renal vein branching was 3%, with a CI of 0% to 6%. Lastly, the prevalence of unusual renal vein origin was 2%, with a CI of 1% to 4%. Conclusions: The analysis of these variants is crucial for both surgical clinical management and the treatment of patients with renal transplant and hemodialysis.

Left Renal Vein Division for Juxtarenal Aortic Exposure: Influence on Renal Function and Role of the Communicating Lumbar Vein

Background

In this study, we evaluate the outcome of renal function in patients undergoing juxtarenal abdominal aortic aneurysm repair with or without division of the left renal vein with special focus on the role of the communicating lumbar vein.

Methods

A retrospective analysis of prospectively collected data of 110 patients undergoing elective juxtarenal abdominal aortic aneurysm repair between 2000 and 2018 was performed.

The demographic characteristics and comorbidities were reviewed in detail and the renal function was analysed pre- and post-operatively. The cohort of patients was split into group A (left renal vein divided) and B (left renal vein mobilised). Group A was further sub-analysed regarding the presence of a communicating lumbar vein on preoperative imaging data (group A+ = vein present, group A− = no communicating lumbar vein present).

Results

The patients were matched well regarding their demographic characteristics and comorbidities. In the analysis of renal function, no statistically significant difference could be detected between group A and B. In the sub-analysis of group A, the group with a communicating lumber vein (group A+) turned out to have a significantly better renal function in the long term (sCrea 0.87 vs. 1.51; p = 0.016).

Conclusion

Ligation of the left renal vein is a safe procedure in surgery of juxtarenal aortic aneurysms regarding the outcome of the renal function. A communicating lumbar vein between the left renal vein and the left ascending lumbar vein seems to play a key role to provide venous drainage after division of the left renal vein.

Curative para-Aortic lymph node dissection Via INfra-mesocolonic approach in laparoscopic Gastrectomy (CAVING approach)

PURPOSE

Para-aortic lymph node (PAN) metastasis for gastric cancer is considered a distant lymph node metastasis. Meanwhile, multidisciplinary treatments have improved survival of patients with PAN metastases. We developed a novel technique of curative para-aortic lymph node dissection via infra-mesocolonic approach in laparoscopic gastrectomy (CAVING approach). This method minimizes the mobilization of the pancreas and the spleen and maximizes the view from the caudal side resembling cave exploration.

METHODS

After laparoscopic gastrectomy, PAN dissection is performed using the same ports setup. The retroperitoneum is widely exposed to ease anatomical cognition and for troubleshooting. The inferior vena cava, the left gonadal vein, the left renal vein, and the aorta are recognized under Gerota's fascia. The retroperitoneum is then divided into four sections. We perform PAN dissection in the order of 16blat, 16b1int, 16a2lat, and then 16a2int. Using the CAVING approach, the caudal side of the root of the superior mesenteric artery can then be dissected below the pancreas, and only the cranial side of the SMA root requires a suprapancreatic approach.

RESULTS

In three cases, preoperative chemotherapy and laparoscopic gastrectomy plus D2 with PAN dissection were performed for gastric cancer and esophagogastric junction cancer. The median operation totaled 484 min, 142 min for the PAN dissection. The median whole blood loss was 130 ml. The median harvested number of PAN was 25.

CONCLUSIONS

The minimal mobilization of pancreas and the wide surgical fields by CAVING approach may facilitate safe and reliable PAN dissection.

Configuration of the extra-renal venous system in relation to the left renal vein: A cadaveric study and new proposed classification

The advent of laparoscopic live-donor nephrectomy for renal transplantation has prompted the need to define the precise anatomical relations of the left renal vein (LRV) and its tributaries. The left kidney is preferred as the greater length of the LRV facilitates implantation in the recipient. While previous studies have described variations in the LRV system, the connections between the left ascending lumbar vein (LALV) and LRV tributaries have been less well-defined. This study aims to further characterise the LALV and proposes a novel classification for its relation to other veins. Dissection of the LRV system, including the left suprarenal vein (LSV), left gonadal vein (LGV) and LALV, was performed in 38 cadavers. Their drainage points into the LRV were recorded, and measurements taken of the distances from these points to the junction of the LRV and inferior vena cava (IVC). The position of the LRV in relation to the aorta was anterior in 35 cases (92%), entirely posterior in 1 case (3%), and circumaortic in 2 cases (5%). Duplication of the LSV and LGV occurred in 6 (16%) and 10 (27%) cases respectively. A direct posterior connection between the LALV and LRV was identified in 32 (86%) cases. The drainage point of the LALV into the LRV lay between the IVC and LGV in 8 (25%) cases. In 20 cases (63%), the drainage points of the LALV and LGV were equidistant from the IVC; and in 5 cases (16%), those of the LALV and posterior branch of the LRV were equidistant from the IVC. In these two groups, the vessels shared a confluent trunk in 10 and 4 cases respectively. In 3 cases, connections were observed between all three vessels (LALV, LGV and posterior branch of LRV). No confluence trunk was shared by the LALV and LSV. These results confirm the high incidence of communicating LALVs, which represent a potentially troublesome source of operative bleeding if unrecognised. Confluent venous trunks may also present difficulties during vessel ligation prior to nephrectomy. It is suggested that a novel classification of the relation of the LALV based on these findings may assist in surgical planning and reduce complications.

Endo-Satinsky Clamp Hybrid In Situ Perfusion in Retroperitoneoscopic Donor Nephrectomy For Right-sided Kidney

OBJECTIVE

To introduce our hybrid technique using an endo-Satinsky clamp and in situ cold perfusion for right-sided retroperitoneoscopic donor nephrectomy (RDN) and to investigate efficacy and safety compared with those standard right-sided RDN.

METHODS

This retrospective study included 16 transplant donors who underwent right-sided RDN from January 2016 to January 2018. Donors received either hybrid RDN (n = 6) or standard RDN (n = 10). Perioperative outcomes, including operative time, estimated blood loss, warm ischemic time, hospital stay, length of renal vein obtained as well as postoperative renal function of their recipients were collected and compared between the hybrid RDN and standard RDN groups.

RESULTS

Procedures were performed successfully in all 16 donors. The hybrid RDN group required longer operation times (135 vs 115 minutes), demonstrated increased blood loss (175 vs 140 mL), but shorter warm ischemic times (1.5 vs 5.5 minutes) and resulted in longer length of the procured renal vein (2.8 vs 1.7 cm) as compared with the standard RDN group. No difference in perioperative complication rates was witnessed between the 2 groups. Also, there were no significant differences in serum creatinine levels and glomerular filtration rates of recipients between the 2 groups at both postoperative day 3 and 1 month.

CONCLUSION

The hybrid RDN potentially extends the length of the right donor renal vein. The perioperative outcomes of hybrid RDN were comparable with those of the standard RDN. This hybrid technique can be a technically safe and feasible option for right kidney donation.

Laparoscopic nephrectomy simplified - A "two-window technique" for safer approach to hilum for a novice

Though the overall safety of laparoscopic nephrectomy (simple or radical) is well established, for a novice it remains a challenge. The classical description of laparoscopic nephrectomy entails dissection either from caudal to cephalad side or vice versa. Herein we describe our "two window technique" for managing renal hilum during laparoscopic (simple/radical) nephrectomy. Our main intention in description of this technique is to reduce the level of apprehension for a novice urologist for performing laparoscopic nephrectomy. After colon mobilization, sequential lower and upper windows are created around the hilum following which hilar vessels are dissected circumferentially when the hilum is at a stretch by traction from either of the window. There are multiple potential advantages of this method which includes easier and safer dissection especially for novice in this field by giving a safety window of application of vascular clamp in cases of vascular bleeds. Intrahilar dissection in stretched condition becomes safer with vision from all around 360° for safe application of Hem-o-lok® clips. Due to the widely exposed field, injuries to adrenal vein and lumbar veins would be minimized and the chances of missed accessory vessel would be minimized. En mass hilar control with vascular clamp in cases of partial nephrectomy is possible with same approach as well as the en block stapling is feasible in cases of nephrectomy. This needs a validation across multiple centers with comparative studies before considering it as a standard of practice. We sincerely believe that this is safe and easily reproducible by a novice.

Retroperitoneal Lymph Node Dissection: Anatomical and Technical Considerations from a Cadaveric Study

PURPOSE

Metastatic testis cancer in the retroperitoneum presents a technical challenge to urologists in the primary and post-chemotherapy settings. Where possible, bilateral nerve sparing retroperitoneal lymph node dissection should be performed in an effort to preserve ejaculatory function. However, this is often difficult to achieve, given the complex neurovascular anatomy. We performed what is to our knowledge the first comprehensive examination of the anatomical relationships between the sympathetic nerves of the aortic plexus and the lumbar vessels to facilitate navigation and nerve sparing during bilateral retroperitoneal lymph node dissection.

MATERIALS AND METHODS

The relative anatomy of the infrarenal vasculature (lumbar vessels, right gonadal vein and inferior mesenteric artery) was investigated in 21 embalmed human cadavers. The complex relationships between these vessels and the sympathetic nerves of the aortic plexus were examined by dissection of an additional 8 fresh human cadavers.

RESULTS

Analysis of the infrarenal vasculature from 21 cadavers demonstrated that the position of the right gonadal vein and the inferior mesenteric artery may be useful to locate the right superior lumbar vein and the first pair of infrarenal lumbar arteries as well as the common lumbar trunk (vein) and the second pair of infrarenal lumbar arteries, respectively. Furthermore, the lumbar splanchnic nerves supplying the aortic plexus were most often positioned anteromedial to the respective lumbar vein.

CONCLUSIONS

The current study describes the complex neurovascular relationships that are crucial to performing successful nerve sparing retroperitoneal lymph node dissection. Surgical techniques are also discussed. Collectively, these results may help surgeons decrease the rate of postoperative retrograde ejaculation and/or anejaculation.

The lumbar arteries and veins: Quantification of variable anatomical positioning with application to retroperitoneal surgery

The lumbar arteries and veins are segmentally arranged vessels in the abdomen that supply the vertebrae and posterior abdominal/paravertebral muscles. Recent studies have indicated that these vessels have a tendency to vary from the classical description of bilateral pairing. The objective of this study was to more accurately characterize the anatomy of the lumbar vessels through the dissection of 22 cadaveric specimens and examination of 41 patients' computed tomography angiography scans. The positions of the lumbar vessels were measured in reference to the bifurcation/confluence of the common iliac arteries/veins. In 22 cadaveric specimens, the course of the lumbar veins was dissected to the psoas major muscle to characterize venous tributaries. Our results indicate that the lumbar veins were rarely paired, segmentally diverged closer to the iliocaval confluence, and preferentially drained into the left side of the IVC. Several types of lumbar veins were additionally characterized based on their consistent coursing patterns. In contrast, the lumbar arteries exhibited pairing, and these successive pairs were found to be equally spaced along the length of the infrarenal abdominal aorta. In specimens where the median sacral artery and 4th lumbar artery pair arose from a trifurcating common trunk, the positions of the 3rd and 4th lumbar arteries were significantly inferior (P < 0.05) compared to those with independent median sacral arteries. Clinically, proper management of the anatomical patterns described in this study may be pivotal in reducing the incidence of intraoperative damage to the lumbar vessels, and may help in the treatment of vascular diseases.

Retroperitoneoscopic donor nephrectomy with a gel-sealed hand-assist access device

Background

The hand-assisted technique enables the rapid extraction of the graft, shortening the warm ischemia time (WIT), and the retroperitoneoscopic approach is potentially associated with a less incidence of postoperative ileus in donor nephrectomy for living kidney transplantation. The aim of this study was to assess the efficacy and safety of retroperitoneoscopic donor nephrectomy with a gel-sealed hand-assist access device (GelPort), which is a wound sealing device that permits the access of the hand to the surgical field, free trocar site choice within it, and rapid conversion to open surgery if necessary, while preserving the pneumoperitoneum/pneumoretroperitoneum.

Methods

Seventy-five consecutive donors receiving this procedure were retrospectively studied. A 2-cm skin incision was made at the midpoint between the tip of the 12th rib and superior border of the iliac bone in the midaxillary line, through which retroperitoneal space was made. Preperitoneal wound with a 6 – 7-cm pararectal incision in the upper abdominal region was connected to the retroperitoneal space. A GelPort was put inside the pararectal surgical wound. The principle was pure retroperitoneoscopic surgery; hand-assist was applied for retraction of the kidney in the renal vessel control and graft extraction.

Results

The mean operation time including waiting time for recipient preparation was 242.2±37.0 (range: 214.0–409.0) min, and the mean amount of blood loss was 164.3±146.6 (range: 10.0–1020.0) ml. The mean WIT was 2.8±1.0 (range: 1.0–6.0) min. The shortage of renal vessels or ureter was observed in none of the grafts. No donor experienced blood transfusion, open conversion, or injury of other organs. Blood loss was greater in patients with body mass index (BMI) of 25 kg/m² or higher than in those with BMI of <25 kg/m² (218.4±98.8 vs. 154.8±152.1 ml, P=0.031). No donor had postoperative ileus or reported wound pain leading to decreased activity of daily life or wound cosmetic problem.

Conclusions

Retroperitoneoscopic hand-assisted donor nephrectomy with the mentioned approach was suggested to be a feasible option without compromising safety, although further improvement in surgical techniques is warranted.