Direct needle insufflation for pneumoretroperitoneum: anatomic confirmation and clinical experience

Risk of Injury to Retroperitoneal Structures in Prone and Lateral Decubitus Transpsoas Approaches to Lumbar Interbody Fusion: A Pilot Cadaveric Anatomical Study

Introduction The retroperitoneal approach for lateral lumbar interbody fusion (LLIF) originally described an initial posterolateral fascial incision enabling finger dissection from behind the peritoneum and guidance of instruments through a second direct-lateral fascial incision. It has since become common for single direct-lateral incisional access to the retroperitoneum. This study attempted to quantify the distance of the peritoneum from posterior landmarks in the space, assess the risk of peritoneal violation in each access trajectory (i.e., posterolateral versus direct lateral retroperitoneal dissection), and determine whether there are differences based on patient position (prone versus lateral decubitus). Methods In three prone cadaveric torsos, Steinman pins were percutaneously placed mid-disc at each level L2-5 bilaterally (for a total of 18 prone approaches). Open dissections exposed the retroperitoneum including the quadratus lumborum and psoas muscles, maintaining the natural reflection of the peritoneum. Visual assessment qualified whether any pin violated any retroperitoneal structure. Distance from the anterior border of the quadratus lumborum to the posterior-most reflection of the peritoneum was measured. For comparison, three additional torsos were positioned in lateral decubitus, and the above steps were repeated, only unilaterally (for a total of nine lateral decubitus approaches). Results In prone, no pin violated the peritoneum; three (3/18 total approaches) violated the kidney, all at L2-3 (3/6 approaches at L2-3). In lateral decubitus, all three L2-3 pins violated the kidney (3/3 approaches at L2-3); five of the six remaining pins from L3-5 violated the peritoneum (totaling eight violations in the nine total approaches). The incidence of any violation was significantly greater in lateral decubitus vs. prone (8/9 vs. 3/18, p=0.0006). The structure at risk (kidney vs. peritoneum) was significantly associated with disc level (p=0.0041): all kidney violations occurred at L2-3 and all peritoneal violations occurred at L3-4 or L4-5. Distance from the quadratus lumborum to the posterior-most reflection of the peritoneum averaged 8.7 cm (range: 6-10) in prone, and 2.9 cm (range: 2.5-3.2) in lateral decubitus (p=0.0129). Conclusion A cadaveric study of retroperitoneal anatomy demonstrates that there is an increased distance from the quadratus lumborum to the peritoneum in prone versus lateral decubitus and that the trajectory of approach to the lumbar discs risks violation of the peritoneum more frequently when accessing directly laterally versus posterolaterally. In either approach, care should be taken to identify and release the peritoneal reflection to create a safe passage to the lumbar discs.

Direct Puncture Tunnel Method for Establishing the Retroperitoneal Cavity: Anatomic Confirmation and Clinical Experience

Purpose: The feasibility and safety of the direct puncture tunnel method to establish the retroperitoneal cavity was assessed by CT and clinical experience. Materials and Methods: Ten patients who underwent retroperitoneoscopic procedure were scanned by CT in the lateral decubitus position. The distance between the lumbar fascia and psoas major muscle (L-P distance) on the puncture line was measured. The angle between the puncture line and the posterior colon margin (P-C angle) was also measured. In total, 292 patients who underwent retroperitoneoscopic procedure were used to establish the retroperitoneal cavity using the direct puncture tunnel method, and complications in these patients were evaluated. Results: The average L-P distance was 25.0 mm (left side) and 25.5 mm (right side) in the lateral decubitus position. The average P-C angle was 26.8° (left side) and 29.7° (right side). The retroperitoneal cavity was well established in all 292 patients, and no visceral or blood vessel injury occurred. Conclusions: CT scans in the lateral recumbent position indicate that there are no visceral and large blood vessels on the puncture path. The scans also provide a window for inserting the first trocar blindly into the retroperitoneum. A high success rate and low complication rate were observed clinically for the direct puncture tunnel method. We consider the direct puncture tunnel method to be a simple, effective, and safe way to establish the retroperitoneal cavity.

Pure Retroperitoneal Optical Access Trocar for Lumbar Diseases in Adults: A Step-by-Step Technique

PURPOSES

The primary end point of this study was to describe step by step the technique of the pure retroperitoneal optical access trocar (PROAT) in adults. The secondary end point was to access between-group differences in perioperative outcomes.

MATERIALS AND METHODS

Forty-five patients underwent retroperitoneoscopic surgery using the PROAT technique to enter the retroperitoneal space (PROAT group). Thirty-nine patients underwent retroperitoneoscopic surgery using the conventional open-Hasson technique with manufactured Hasson-trocar and space-maker balloon to enter and create the retroperitoneal space (conventional group). PROAT technique was described. Data were prospectively collected and analyzed.

RESULTS

Mean time for first-entry trocar insertion was lower in the PROAT group (9.76±3.17 vs. 23±7.2 s; P<0.001). Mean time to develop the retroperitoneal space until all-trocar placement was higher in the PROAT group (12.7±3.3 vs. 6.4±2.2 min; P<0.001). Carbon dioxide gas leakage was not observed.

CONCLUSIONS

The PROAT technique is feasible and safe. This approach can potentially avoid carbon dioxide leakage when manufactured Hasson trocars are not available and allow a reduced-cost procedure.

Laparoscopic approaches in urology

The use of laparoscopy was one of the most important steps in the progress of medicine, and has developed through the 20th century. Gynaecologists took the initial lead in introducing this technology, followed by general surgeons. Since the first laparoscopic nephrectomy in 1990, most ablative and reconstructive urological surgery has been attempted laparoscopically. Laparoscopic urological surgical approaches include conventional transperitoneal and extraperitoneal; in this review the different approaches, with the relevant anatomical considerations, are discussed.

Laparoscopic retroperitoneal adrenalectomy: clinical experience with 120 consecutive cases

OBJECTIVE

Surgical parameters of laparoscopic retroperitoneal adrenalectomy (LRA) for the treatment of benign adrenal tumours were analysed to report the clinical outcomes and technical guidelines for this operation.

METHODS

Operative data from 120 consecutive patients who underwent LRA performed by a single surgeon were reviewed. Patients were categorized into one of four stages according to the major technical modifications made during the development of this procedure: needle insufflation, kidney localization, instrument refinement, and the final stage of finger dissection. The surgical parameters of different stages were evaluated, including operation time, operative blood loss, adenoma size, pathology, surgical complications, morbidity, and postoperative recovery.

RESULTS

LRA was an evolving technique; operation time and conversion rate decreased gradually as the technique evolved over the years. Operation time was reduced particularly when finger dissection was used to develop the operative working space. Operation time reached a nadir of 80 minutes for patients with left adrenal aldosteronoma after 40 such cases. The overall conversion rate, regardless of the nature of the tumour, was 5%; phaeochromocytoma had the highest conversion rate (43%). A higher conversion rate and longer operation time were noted in patients with Cushing's adenoma or phaeochromocytoma compared to patients with aldosteronoma.

CONCLUSION

LRA proved to be a safe and effective treatment for benign adrenal tumours, with few open conversions except for phaeochromocytomas. Finger-assisted dissection for space development was the major factor leading to shortened operation times.

A modified access technique for retroperitoneoscopic renal surgery in children

PURPOSE

Present techniques for retroperitoneal endoscopic (RPE) access in children mimic those in adults but often result in peritoneal entry or gas leaks, both of which lead to a decrease in the retroperitoneal space. We describe a modification to the access technique that obviates these problems, thus, facilitating RPE in children.

MATERIALS AND METHODS

In the lateral decubitus position the initial port is placed immediately lateral to the paraspinal muscles, similar to open dorsal lumbotomy fascial incision. A 5 mm skin incision is made at the level of the costovertebral angle and an artery forceps used to tunnel bluntly past the lumbodorsal fascia. A 5 mm port is placed with a blunt trocar, and expansion of the retroperitoneal space performed with the telescope and gas insufflation. Ancillary ports are placed and the telescope then moved to an anterior subcostal port where popular RPE approaches place the initial port.

RESULTS

Eighteen procedures were performed in children with a mean age of 10.8 years, including 12 nephrectomies, 3 dismembered pyeloplasties, 1 partial nephrectomy, 1 nephroureterectomy and 1 parapelvic cyst decortication. No gas leaks occurred, with 1 minor peritoneal entry early in the series not related to the access. Average surgical time for nephrectomy was 178 minutes (range 120 to 240). No intraoperative complications occurred.

CONCLUSIONS

We present a safe and effective technique of initial port placement that follows the principles of open lumbotomy exposure. This approach to RPE minimizes peritoneal entry and gas leaks, thus, maximizing surgical exposure.

Retroperitoneal laparoscopic adrenalectomy

Retroperitoneoscopic adrenalectomy is currently performed either by lateral flank approach or posterior lumbar approach. The retroperitoneal laparoscopic adrenalectomy avoids invading the intraperitoneal cavity and possible injury to the abdominal organs. The posterior lumbar approach allows direct access to the main adrenal vascular supply before the gland is manipulated. Retroperitoneal laparoscopic adrenalectomy by the posterior approach is technically feasible and most effective as regards the simplicity of vascular control. The lateral flank approach allows a more spacious working cavity, but a large tumor obscures the surgical plane to the adrenal vessels. The transection of the adrenal vein is performed at the end of the procedure. The operating time, perioperative morbidity and cost have been reduced with these retroperitoneal approaches. The retroperitoneal approach to the adrenal gland is technically simple and can be performed quickly, with a low postoperative morbidity and should be regarded as the routine approach for relatively small adrenal benign tumors that are less than 5 cm in diameter.

Comparison study on two different accessing methods for retroperitoneoscopic adrenalectomy

OBJECTIVES

To compare, in a retrospective nonrandomized study, two retroperitoneal laparoscopic access methods for treatment of adrenal tumors: direct needle insufflation with balloon dissection and finger-assisted dissection without balloon dissection.

METHODS

The operative data from 120 consecutive patients undergoing retroperitoneoscopic adrenalectomy (RA) for benign adrenal tumors were reviewed. The operative outcomes of 70 RAs accessed by direct needle insufflation and balloon dissection were compared with another 50 RAs accessed by finger dissection without balloon dissection. The RA surgical parameters for tumors with different laterality, pathologic features, and size were also analyzed.

RESULTS

The operative time in the finger dissection group was shorter (118 +/- 11 minutes) compared with that in the balloon dissection group (143 +/- 21 minutes; P = 0.03). The surgical parameters, including incidence of peritoneal perforation, intraoperative blood loss, time to oral intake, analgesic requirement, postoperative hospital stay, and convalescence, did not differ between the groups. For tumors greater than 5 cm, the operative time increased to 220 +/- 30 minutes compared with 132 +/- 31 minutes for tumors 5 cm or less (P = 0.02). The finger and balloon dissection methods had similar operative times for tumors larger than 5 cm (218 +/- 10 versus 224 +/- 15 minutes). No additional morbidity regarding the recovery time was noted in the finger dissection group compared with the balloon dissection group.

CONCLUSIONS

Finger dissection appears to be a more efficient and equally effective access method for RA compared with balloon dissection. We suggest that balloon dissection may not be required for RA in patients not excessively obese.

Laparoscopic radical nephrectomy: retroperitoneal versus transperitoneal approach

Laparoscopic radical nephrectomy can be efficaciously performed by either the transperitoneal or the retroperitoneal laparoscopic approach. The primary indication for selecting one approach over another has historically depended on the individual surgeon's experience and training. With either technique, laparoscopy adheres to established surgical oncologic principles of wide specimen mobilization and early vascular control. This article reviews the history, contraindications, anatomic considerations, patient preparation, and surgical technique of these two laparoscopic approaches. A salient summary of the worldwide experience with these procedures is presented, as well as a brief synopsis of controversial arguments favoring specimen morcellation versus intact extraction.

Retroperitoneoscopy versus laparoscopy in piglets: ventilatory and thermic repercussions

BACKGROUND/PURPOSE

Endoscopic surgery of the retroperitoneal space in children is developing. During preliminary clinical experience, the authors were surprised by the differences observed in comparison with laparoscopic pneumpoeritoneum (PNOP); retropneumpoeritoneum (RPNOP) seemed to have less ventilatory repercussions.

METHODS

The authors therefore undertook a study on animal models. Six suckling pigs, newly weaned, each weighing 10 kg successively underwent, at 8-day intervals and in random sequence, a right RPNOP with kidney and vena cava dissection, with insufflation of CO2 at 10 mm Hg of pressure and a PNOP with the same pressure of 10 mm Hg.

RESULTS

P(ET)CO2 increased during PNOP, and it remained stable during during RPNOP (P = .035). The ventilatory peak airway pressures (PawP) increased during PNOP, but were not modified during RPNOP (P = .0001). Temperature decreased with time (P = .0001) without difference between the two procedures (P = .34).

CONCLUSIONS

RPNOP was not associated with any adverse effects on the ventilation despite the insufflation pressure of 10 mm Hg, which allowed a satisfactory working area to be created. Operations by RPNOP could be developed in children with fewer respiratory repercussions than those observed during laparoscopy at an equivalent level of pressure.

Retroperitoneal and pelvic extraperitoneal laparoscopy: an international perspective

OBJECTIVES

To assess technical preferences and current practice trends of retroperitoneal and pelvic extraperitoneal laparoscopy.

METHODS

A questionnaire survey of 36 selected urologic laparoscopic centers worldwide was performed.

RESULTS

Twenty-four centers (67%) responded. Overall, 3988 laparoscopic procedures were reported: transperitoneal approach (n = 2945) and retroperitoneal/extraperitoneal approach (n = 1043). Retroperitoneoscopic/extraperitoneoscopic procedures included adrenalectomy (n = 74), nephrectomy (n = 299), ureteral procedures (n = 166), pelvic lymph node dissection (n = 197), bladder neck suspension (n = 210), varix ligation (n = 91), and lumbar sympathectomy (n = 6). Mean number of total laparoscopic procedures performed in 1995 per center was 41 (range 5 to 86). Major complications occurred in 49 (4.7%) patients and included visceral complications in 26 (2.5%) patients and vascular complications in 23 (2.2%). Open conversion was performed in 69 (6.6%) patients, electively in 41 and emergently in 28 (visceral injuries, n = 16; vascular injuries, n = 1 2). Retroperitoneoscopy/extraperitoneoscopy is gaining in acceptance worldwide: in 1993, the mean estimated ratio of transperitoneal laparoscopic cases versus retroperitoneoscopic/ extraperitoneoscopic cases per center was 74:26; however, in 1996 the ratio was 49:51.

CONCLUSIONS

Retroperitoneoscopy and pelvic extraperitoneoscopy are important adjuncts to the laparoscopic armamentarium in urologic surgery. The overall major complication rate associated with retroperitoneoscopy/extraperitoneoscopy was 4.7%.

Retroperitoneal laparoscopic nephrectomy

When removal of a kidney is indicated for symptomatic end-stage renal disease of benign etiology, laparoscopic nephrectomy by the retroperitoneal approach is increasingly being employed as the technique of choice at many centers. Emerging data indicate that, in select patients with T1-T3aN0M0 renal tumors < 8 cm, retroperitoneal laparoscopic radical nephrectomy may be a viable treatment option.