Indian Journal of Vascular and Endovascular Surgery

INVITED COMMENTARY
Year
: 2020  |  Volume : 7  |  Issue : 3  |  Page : 211--215

Retroperitoneal approach to the abdominal aorta: Tips and tricks


Aniket Pradhan, Sewa Singh, Nandan Haldipur 
 Department of Vascular and Endovascular Surgery, Doncaster and Bassetlaw Hospitals NHS Foundation Trust, Doncaster, UK

Correspondence Address:
Nandan Haldipur
Department of Vascular and Endovascular Surgery, Doncaster and Bassetlaw Hospitals NHS Foundation Trust, Doncaster
UK

Abstract

In the era of endovascular repair of abdominal aneurysms (AAA) the use of traditional open surgical repair of AAA is declining. The preferred option for patients with AAAs who are young or have challenging anatomy that is not suitable for Endovascular repair is open surgical repair. Most Vascular Surgical units are familiar with the transperitoneal (TP) approach to AAA. Another useful approach to AAA is retroperitoneal (RP). Our unit has found RP a more suitable approach for repairing the AAAs with challenging anatomy and in patients with poor physiological function. RP approach provides excellent access to the juxta/supra renal aorta. In addition, patients undergoing RP have less post-operative morbidity and shorter hospital stay compared to those undergoing TP repair. Our unit recommends RP approach as the preferred option to repair AAAs unsuitable for endovascular repair. Given the relative lack of familiarity with this technique as it is not widely practised, we have described the technique/our experience and its advantages over conventional open surgery.



How to cite this article:
Pradhan A, Singh S, Haldipur N. Retroperitoneal approach to the abdominal aorta: Tips and tricks.Indian J Vasc Endovasc Surg 2020;7:211-215


How to cite this URL:
Pradhan A, Singh S, Haldipur N. Retroperitoneal approach to the abdominal aorta: Tips and tricks. Indian J Vasc Endovasc Surg [serial online] 2020 [cited 2020 Sep 29 ];7:211-215
Available from: http://www.indjvascsurg.org/text.asp?2020/7/3/211/294922


Full Text



 Introduction



In the early 1950s, Cooley and De Bakey[1] resected saccular aneurysms and repaired the arterial walls by lateral suture. Since then, there have been significant advances in aortic surgery. Various approaches to the aorta have been described which broadly can be classified as transperitoneal (TP) or retroperitoneal (RP).

In recent times, intervention for aneurysmal disease has been dominated by endovascular aneurysm repair (EVAR). Despite the development of endovascular techniques for abdominal aortic aneurysm (AAA) repair, open surgical repair remains necessary to treat anatomically complex aneurysms and may be beneficial for younger patients and those unable to comply with long-term surveillance. Not all aneurysms have a favorable anatomy for a simple EVAR procedure and may require a complex endovascular procedure or open surgery. RP access is especially suited for challenging necks as the approach facilitates better access to the suprarenal aorta. The evidence also suggests that the RP approach is better in patients with compromised respiratory function as it reduces postoperative morbidity and shortens postoperative stay when compared with transperitoneal repair.[2]

With increasing EVARs, the number of open aortic surgical procedures has reduced dramatically. Patients undergoing open surgery these days are inevitably either young or have challenging anatomy, and as a consequence, the open procedures are often more challenging due to obesity, calcified vessels, and poor-quality necks requiring supra/intrarenal clamps.

The transperitoneal approach is most familiar to surgeons and provides good intraperitoneal access. It has been the standard approach to open aneurysm repair. The RP approach is practiced in fewer centers, and consequently, expertise in the technique is limited. With the decreasing number of aneurysms in the UK population and restriction of training hours, this expertise is likely to diminish even further. Our unit has been performing RP AAA repair for more than two decades and is one of the few centers in the UK that offers RP repair to patients with AAAs.

 Our Experience With Rp



This review is aimed at sharing our experience of RP approach to AAA repair.

The threshold for repairing an AAA in our unit is an orthogonally measured aneurysm diameter of 5.5 cm or more. Smaller aneurysms that are intervened upon are either symptomatic or saccular. A combination of a thorough medical history and investigations which include pulmonary function tests and echocardiogram is used to assess the surgical fitness of the patient. A planning computed tomography (CT) aortogram is requested to plan intervention. This is an arterial phase CT which includes the entire aorta to the superficial femoral artery.

 Rp Approach Patient Selection



Patients selected for RP repair usually have an anatomically unsuitable neck for an EVAR. RP is our preferred approach in patients who require an intrarenal or suprarenal clamp [Figure 1]. We find the exposure to the pararenal aorta, and even supraceliac aorta is much easier with the RP approach. RP is our preferred approach in patients with a “hostile” abdomen which includes previous laparotomies, incisional hernias, previous intra-abdominal sepsis, stomas, and in general any cause for extensive intra-abdominal adhesions. The approach is also useful in morbidly obese patients as the intra-abdominal contents tend to fall away from the aorta due to the positioning of the patient.{Figure 1}

In addition, this approach is also beneficial in patients who have compromised pulmonary function tests. Postoperatively, patients undergoing RP repair have less pain, and consequently, chest physiotherapy and coughing are more effective.

Access to the right common iliac artery is difficult with the RP approach [Figure 2] and therefore is not the preferred approach in the presence of a right common iliac artery aneurysm or occlusion.{Figure 2}

In other words, it is not the preferred approach if a bifurcated graft needs to be implanted in the distal iliac arteries.

 Procedural Tips



This technique requires an operating table with a kidney bridge and all the accessories to support a patient in the lateral position. We place the anesthetized patient on a bean-bag device (Olympic Vac-Pac 68035, Olympic Medical, Seattle, WA, USA) with the hips parallel but rotated to so that the pelvis is rotated 45° with the left hip higher than the right [Figure 3]. The torso and left shoulder are further rotated so that the shoulders are at 60° to the horizontal with the left shoulder uppermost. The table is then fully broken, with the head and legs as low as possible, and the apex of the table is between the iliac crest and the 12th rib, to open up the space between the coastal margin and the iliac crest.{Figure 3}

The incision starts at the lateral edge of the rectus abdominis approximately midway between the umbilicus and the pubic symphysis and then extends posterolaterally toward the 11th and the 12th rib [Figure 4]. These ribs can be excised if further exposure is required. Diathermy is then used to dissect through the abdominal musculature. A plane is then developed between the posterior abdominal wall and the posterolateral peritoneum displacing the left kidney, the ureter, tail of the pancreas, and the spleen anteriorly. This is done by a combination of sharp and blunt dissection by gently sweeping the tissue in front of the posterior abdominal wall using a pack and cauterizing bleeding vessels with diathermy. Any breach in the peritoneum at this stage is sutured with vicryl. Exposure of the aorta and retraction of the abdominal wall and abdominal contents is greatly aided using self-retaining retraction systems. Increased exposure is facilitated by retraction of the abdominal musculature outward and upward. The dissection is then continued anterior and medial to the psoas muscle to reach the side wall of the aorta. This dissection is continued cranially to the neck and caudally to the aortic bifurcation. The periaortic fat is vascular and is carefully dissected to ensure good hemostasis. The left gonadal vein needs ligation to expose the left renal artery and thus the neck of the aneurysm [Figure 5] and [Figure 6].{Figure 4}{Figure 5}{Figure 6}

The common iliac arteries are then dissected out. The left common iliac can usually be displayed down to its bifurcation into internal and external iliac [Figure 7]. A clamp can be applied to the left common iliac or the internal and external iliac arteries can be controlled and clamped individually. If the left common iliac artery is aneurysmal or occluded, repair can be affected down to the bifurcation. If dissection of the right common iliac artery proves difficult, control can be obtained by inserting an intraluminal Foley catheter and inflating the balloon gently.{Figure 7}

 Discussion



The first open abdominal procedure was described by Dubost et al.[3] in 1952 using a TP approach. It is the most common approach to the intra-abdominal aorta and is used by most vascular and general surgeons. It gives excellent exposure of the infrarenal aorta, iliac, renal, and visceral arteries.

Rob[4] published his series of 500 patients with RP approach in 1963 concluding that this exposure offered many advantages over a midline incision. Stipa and Shaw[5] described the RP approach in 45 patients with no deaths.

Recently, in 2003, Shaw et al.[6] have validated the advantages of the RP approach. They also suggested a more posterolateral incision extending into the ninth intercoastal space to access the suprarenal or supraceliac aorta.

 Advantages of Rp Approach



Twine et al.[7] and other authors have described the advantages of this approach. It gives excellent exposure of the abdominal aorta up to the supraceliac level, without entering the peritoneum. In addition, it also provides easy access to the aortic bifurcation, left iliac artery, and the left renal artery. The inferior vena cava remains outside the area of dissection reducing the chance of iatrogenic injury.

Technical challenges presented by a hostile abdomen during TP approach due to previous laparotomies, stomas, and incisional hernias are completely eliminated as the peritoneum is reflected anteriorly. The transverse incision involves fewer dermatomes than a mid-line incision, therefore giving better pain management postoperatively. This is advantageous for patients who are at high risk following open surgery due to respiratory or cardiac comorbidities.[6]

RP approach should also be considered in patients with inflammatory aneurysms as the fibrosis mainly affects the anterior wall sparing the lateral wall making the dissection easier in the RP plane. Redo aortic surgery following previous TP approach may be easier with access to more proximal aorta.[8]

Several studies have claimed physiologic advantages of the RP approach over the TP approach. Patients in one RP group had decreased intraoperative blood loss, fluid requirement, and need for transfusion.[9] Prolonged ileus, nasogastric tube requirement, increased intensive care unit (ICU) stay, length of stay, and complication rate were all more common in patients in whom the TP approach was used.[8],[10] One group demonstrated negative physiologic effects, such as decreased systemic vascular resistance, which can result in increased myocardial oxygen demand, with the TP approach. This has been attributed to the mesenteric traction and intestinal manipulation.[11] Differences in sexual function are unknown.

High-risk patients anatomically not suitable for EVAR undergo RP surgery in our center with acceptable results.

 Disadvantages of Rp Approach



RP approach can be a challenging technique to master. Appropriate patient positioning and ensuring that the incision is made in the right place to access the bed of the 11th or 12th ribs is very important. Anatomical orientation of the organs requires experience of the procedure. Access to the right renal artery and right common iliac artery is limited. However, careful retraction of peritoneum and dissection of the ureter and ligation of the inferior mesenteric artery can give access to the distal left common iliac artery. Access to femoral artery on the right side requires changing the patient position from lateral to supine.

Since there is no access to the peritoneal cavity, the intraperitoneal organs cannot be inspected. Anomalous venous inferior vena cava anatomy needs to be carefully identified on the preoperative CT. Some patients present with a postoperative bulge at the site of the incision. This is either due to an incision hernia which has a higher incidence with RP as compared to TP repair or due to abdominal wall nerve injury.[12]

 Conclusions



Despite advances in interventions for AAAs, RP repair remains a useful approach in selected patients. In these patients, our experience like that of others has shown the approach offers technical benefits which include excellent exposure of the aortic neck providing clamp space in suprarenal area for difficult neck anatomy, relatively easy access to the aorta in a scarred abdomen, and less intraoperative physiological disturbance as the peritoneal cavity is not exposed. Patient benefits include early recovery due to less postoperative pain facilitating early mobility and reduced respiratory and cardiorespiratory morbidity. This leads to reduce intensive care/hospital stay in turn resulting in reduced costs.

However, experience of the procedure is limited to a few centers.

With the increasing use of EVAR, the number of open aortic surgery has gone down drastically providing far fewer opportunities for the trainees to participate. In addition, patients selected for open aortic surgery are more complex demanding experienced senior input. Compounding the above, the stringent rules limiting the working hours of trainees maintained by the European Working Time Directive[13] have reduced the training opportunities in countries such as the UK. Trainers have to work within these constrains and ensure that future generations of vascular surgeons have the adequate expertise to perform the procedure.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1DE Bakey ME, Cooley DA. Surgical treatment of aneurysm of abdominal aorta by resection and restoration of continuity with homograft. Surg Gynecol Obstet 1953;97:257-66.
2Shaw PM, Veith FJ, Lipsitz EC, Ohki T, Suggs WD, Mehta M, et al. Open aneurysm repair at an endovascular center: Value of a modified retroperitoneal approach in patients at high risk with difficult aneurysms. J Vasc Surg 2003;38:504-10.
3Dubost C, Allary M, Oeconomos N. Resection of an aneurysm of the abdominal aorta: Reestablishment of the continuity by a preserved human arterial graft, with result after five months. AMA Arch Surg 1952;64:405-8.
4ROB C. Extraperitoneal approach to the abdominal aorta. Surgery 1963;53:87-9.
5Stipa S, Shaw RS. Aorto-iliac reconstruction through a retroperitoneal approach. J Cardiovasc Surg (Torino) 1968;9:224-36.
6Shaw PM, Veith FJ, Lipsitz EC, Ohki T, Suggs WD, Mehta M, et al. Open aneurysm repair at an endovascular center: Value of a modified retroperitoneal approach in patients at high risk with difficult aneurysms. J Vasc Surg 2003;38:504-10.
7Twine CP, Lane IF, Williams IM. The retroperitoneal approach to the abdominal aorta in the endovascular era. J Vas Surg 2012;56:834-8.
8Leather RP, Shah DM, Kaufman JL, Fitzgerald KM, Chang BB, Feustel PJ. Comparative analysis of retroperitoneal and transperitoneal aortic replacement for aneurysm. Surg Gynecol Obstet 1989;168:387-93.
9Arko FR, Bohannon WT, Mettauer M, Lee SD, Patterson DE, Man-ning LG, et al. Retroperitoneal approach for aortic surgery: Is it worth it? Cardiovasc Surg 2001;9:20-6.
10Sicard GA. Surgical techniques for repair of abdominal aortic aneurysms. In: Gewertz BL, Schwartz LB, editors. Surgery of the Aorta and Its Branches. 1st ed. Philadelphia, Pa: Saunders; 2000. p. 124-36.
11Hudson JC, Wurm WH, O'Donnell TF, Shoenfeld NA, Mackey WC, Callow AD, et al. Hemodynamic and prostacyclin release in the early phases of aortic surgery: comparison of transabdominal and retroperitoneal approaches. J Vasc Surg 1988;7:190-8.
12Gardner GP, Josephs LG, Rosca M, Rich J, Woodson J, Menzoian JO. The retroperitoneal incision. An evaluation of postoperative flank 'bulge'. Arch Surg 1994;129:753-6.
13Blencowe NS, Parsons BA, Hollowood AD. Effects of changing work patterns on general surgical training over the last decade. Postgrad Med J 2011;87:795-9.