International Journal of Cardiovascular ResearchISSN: 2324-8602

All submissions of the EM system will be redirected to Online Manuscript Submission System. Authors are requested to submit articles directly to Online Manuscript Submission System of respective journal.

Research Article,  Int J Cardiovasc Res Vol: 6 Issue: 4

Effect of Lumbar Drainage on the Outcome of Thoracic Endovascular Aortic Repair (TEVAR): Contemporary Results

Tamer Owais1,5*, Ashraf Fawzy1,4, Waled Saad3, Mahmoud Salah El Din2, Farouk AL Alfy3, Jürgen Fuchs6, Martin Breuer5 and Thomas Kuntze5

1Cardiothoracic Surgery Department, Cairo University Hospitals, Cairo, Egypt

2Vascular Surgery Department, Saudi German Hospital, Jedah, Saudi Arabia

3Vascular Surgery Department, Saudi German Hospital, Madinah Munawarah, Saudi Arabia

4Cardiothoracic Surgery Department, Saudi German Hospital; Madinah Munawarah, Saudi Arabia

5Department of Cardiac Surgery, Central Clinic of Bad Berka, Germany

6Department of Anesthesia, Central Clinic of Bad Berka, Germany

*Corresponding Author : Tamer Owais
Associate Professor , Department of Cardiac Surgery, Central Clinic Bad Berka, Robert-Koch Allee 9, 99437 Bad Berka, Germany
Tel: 00491622397476; 049036458541115
E-mail: [email protected]

Received: June 05, 2017 Accepted: June 21, 2017 Published: June 26, 2017

Citation: Owais T, Fawzy A, Saad W, Din MSE, Alfy FA (2017) Effect of Lumbar Drainage on the Outcome of Thoracic Endovascular Aortic Repair (TEVAR): Contemporary Results. Int J Cardiovasc Res 6:4. doi: 10.4172/2324-8602.1000315

Abstract

Background: Despite the utmost development and arousal of new techniques as TEVAR in the management of lethal aortic aneurysms and dissecting aortic aneurysms using, we still need to optimize the results through better spinal cord protection for the possible intercostal arteries especially the Adamqiewckz artery. Here we are focusing on the impact of spinal cord protection on the outcome in cases of TEVAR.
Materials and methods: Between May 2007 and May 2017; in Saudi German Hospital (SGH); Madina Munawarah, KSA and central clinic in Bad Berka; Germany. 41 TEVAR procedures were performed. Medtronic Valiant device with the Captiva delivery system was recently used to manage variety of cases of aortic dissection (6 trauma cases, 27 cases of hypertension induced nonaneurysmal dissection , 6 cases of dissecting aortic aneurysms due to hypertension and 2 cases of descending aortic aneurysm and tortuousity). Some of the cases required vascular intervention for de-branching of the great vessels. All patients were submitted to CT angio (CTA) for whole aorta from the ascending to the pelvic part, trans-sternal 2D echocardiography, abdominal ultrasonography; coagulation profile, kidney and liver profiles. Lumbar drainage was used in all the cases. Medtronic devices were used in all the cases.
Results: All patients were males. Age ranged from 24 to 57 years old. All patients were operated under general anesthesia. There were two mortalities one due to major endoleak and multi-organ failure and the other was due to massive Intracranial Hemorrhage (ICH). Three cases of permanent paraplegia early after the procedure. Three cases of renal failure and one impaired kidney functions. One patient had CSF leak. One case had local infection at the lumbar catheter site and one case of meningitis.
Conclusions: Lumbar drainage procedure is an easy but not complications-free procedure. Because of the seriousness of its complications, it is recommended to avoid in TEVAR procedures, as the paraplegia complication due to cord ischemia for which we used the lumbar drainage was unavoidable by the lumbar drainage as it was related mainly to the anatomical site of the aortic injury and its extent or to the area covered by the endograft. There was a mortality of ICH (mostly related to the lumbar drainage).

Keywords: Aortic dissections; TEVAR; Lumbar drainage; CSFP; SSEPs

Introduction

The history of the aortic aneurysms was described in the Pharaohs Hieroglyphic texts, centuries before Christ. They attested it as a highly fatal disease. It was not before 1888 when Rudolph Matas proposed a surgical procedure (endoaneurysmorraphy) for the management of the vascular aneurysms containing thrombus. It was the world - war II, the invention of the heart lung machine and the cardiopulmonary bypass (CPB) and Michael DeBakey and Denton Cooley who lightened the way for the proper management of aortic and vascular pathologies. Moreover, the introduction of vascular grafts, the advances in the imaging techniques and the other diagnostic tools enable cardiovascular surgeons to properly treat such pathologies [1].

After all these advances still the outcome is unfavorable with surgery due to the high rate of intra and post operative mortality and morbidity. In 1994 Dake and his colleagues [2] introduced the new non surgical procedure of the thoracic endovascular repair (TEVAR) to treat aortic aneurysms and dissections with less mortality and morbidity. It was FDA approved in 2005 and restrictions for manufacturing and sale was set by the FDA. Still there is an incidence of paraplegia with the TEVAR procedures especially in long devices or thoraco-abdominal devices [2].

Aortic dissection, aneurysms or dissecting aneurysms are highly lethal without definite incidence registered. The etiologies, the natural history and the total number of registered cases are underestimated due to no registry of miss-diagnosed and passed away cases without being diagnosed. According to the International Registry of Acute Aortic Dissection (IRAD); the etiology, the proposed risk factors and the incidence are all underestimated due to the non-registered and incomplete inclusion prior to admission [3].

After all advances in surgical techniques, surgeons still face the problem of many devastating complications and one of them is the paraplegia. Despite rare yet it is a catastrophic to the patient and his family, its incidence is lower in pathologies below the renal artery or high in the thoracic aorta far-away from the diaphragm, the incidence is also higher in emergency cases(1.4% -2.0%) than in the elective cases(0.1-0.2%) [4].

It is reported that the incidence of paraplegia is high in patients submitted for surgical repair or even endovascular stenting of thoraco-abdominal aortic aneurysms and/or dissection (22% after surgical repair). The etiology may be attributed to the anatomy and involvement of the spinal cord arterial supply due to the dissection, aneurysm or the repair itself. The post procedure paraplegia carries a low survival rate and its exact mechanism after repair is not well understood [5].

Since the introduction of the TEVAR procedure, the incidence of complications has been decreased significantly. With the TEVAR procedure decreased complications yet there is still high incidence of paraparesis or paraplegia after the procedure. It was reported in many series that its incidence is lower than the surgical repair but still as high as 13%. Using proactive cord protection protocols, the incidence of paraplegia was decreased to 1.1% [6].

The proactive spinal cord protective protocols are necessary but the more determinant in the etiology of the occurrence of paraplegia is the anatomy of the spinal cord blood supply and the area covered with the endograft [6].

Anatomical considerations

The blood supply of the cord is the key point in occurrence of paraplegia. The cervical, thoracic and lumbar vessels give small branches (segmental radicular) which in turn give the anterior and two posterior spinal arteries. Adamkiewicz artery arises from the left intercostal artery in 75% of patients, it has a characteristic hairpin bend and it is the largest radicular artery arising variably from T 7 to L4 and mostly at T10. The longitudinal anterior spinal artery (arising from the vertebral artery) runs along the cord anastomosing with the radicular divisions. The posterior inferior cerebellar artery gives the two posterior spinal arteries with poor connection between the anterior and the two posterior spinal arteries. Due to this poor communications, when there is anterior spinal artery jeopardize, the anterior horn of the spinal cord is affected causing paralysis [7].

The knowledge of the cord blood supply and the advent of some new procedures for spinal cord protection lowered the incidence of paralysis. One of these ancillary techniques is the CSF drainage. Most of the reports were discussing this concept in surgical repair with a controversies. The CSF drainage decreases the CSFP(CSF pressure) which leads to increased CSFPP(CSF perfusion pressure). In some experimental reports on dogs creating spinal cord ischemia and crossclamping the aorta, there was improved perfusion pressure and less post perfusion hyperemia of the spinal cord using CSF drainage with less incidence of paralysis [8-11]. Other clinical studies concluded different results and this may be due to other factors affecting the spinal cord protection [12-14].

Despite the overall reduced complications of TEVAR compared to open repair yet the incidence of paraplegia still exist even with lower rates [15]. There is debate about its value as the recorded mortality of the lumbar drainage is ranging from 0% to 11% which denotes a bias about the technique. Other complications reported were; catheter fracture(0-1.8%),local infection or fatal meningitis(0-1.2%), CSF leak(0-2.5%), Abducens nerve palsy(0-0.6%),neuraxial hematoma(0- 3.2%),asymptomatic intracranial hemorrhage; ICH(0-2.9%)and symptomatic ICH(0-5.5%) [16-19].

With the progress and wide range use of TEVAR devices many reported the same complications with almost the same incidence [20].

Patients and methods

Between May 2007 and May2017 in Saudi German Hospital Madinah and central clinic in Bad Berka Germany, 41 cases of TEVAR procedures were performed. Data of patients were revised. Of the 41 patients: 4 cases were victims of motor vehicles, one case fall from heights, one case due to gas tank explosion and the remaining 35 cases were hypertensive patients presented with acute dissection (27 cases) or dissecting aortic aneurysms(6cases) and tortuous and irregular dilatations in 2 cases. All patients were admitted through the ER as they were either RTAs ambulance referred cases or severe hypertension with symptoms related to the dissection (CNS, limb ischemia and severe chest or back pains).

Inclusion criteria

■ Grade I and grade II aortic injuries.

■ Type A aortic dissection with no coronary or aortic valve involvement.

■ Type B aortic dissections.

■ Descending thoracic aortic injuries.

■ Prior CABG with patent LIMA to LAD.

Exclusion criteria

■ Failed lumbar catheter insertion.

■ Spine anomalies (scoliosis or kyphoscoliosis).

■ Paraplegia: either due to the dissection prior to the procedure or in trauma patients who had dorsal spinal injuries.

■ Unconscious patients due to great vessels involvement in type A dissection or head trauma in RTA patients.

■ Post graft open aortic repair: surgical repair of the aorta after endograft; due to graft complications (major endoleak) or other reasons for surgical aortic intervention(re-dissection or another evolving aneurysm).

■ Pre-graft insertion surgical repair of aortic injuries.

■ Endoleak, graft displacement or graft migration with need for another surgical repair.

■ Prior neurological complications (severe head trauma, brain edema or ICH).

■ Previous CVS.

Pre-procedure investigations

-CBC. –Coagulation profile. –Liver and kidney profile. –Thyroid profile. –Cardiac enzymes.

-CTA (CT angiography). –Trans-thoracic 2-D echocardiography. – 12 leads ECG. –Abdominopelvic sonar. –Carotid duplex. –CT brain. –CT whole spine.

No MRI performed for any of the cases. All patients were submitted for thorough neurological assessment by neurology and neurosurgery consultants.

Technique of the TEVAR

The used devices were variable in the cases. From 2007 to 2009 we used 6 endografts from W. L. Gore TAG endograft system; Flagstaff, Ariz. USA. From 2009 to 2016 we use the Medtronic Talent thoracic endograft; Santa Rosa, Calif. USA. And the Valiant system with the Captiva delivery system was used in the late 2016 to 2017.

The procedures were carried out in the Cath. Lab. room under strict aseptic conditions. All the patients were under general anesthesia. In the supine position, groin areas were sterilized to the mid-thigh and up to the level of the umbilicus. The genital areas were carefully covered.

The right Radial artery was cannulated and the BP was monitored; both invasively and by cuff connected to the monitor for 15 minutes regular reading. CVP triple lumen line was inserted and connected to a transducer to measure the CVP. Heparin IV was given (average dose was 400 units/Kg.). The ACT range was 200-400 seconds. Both groins were infiltrated with local anesthetic (Lidocaine 2%) over the femoral artery without invading it. A 4F sheath was introduced in the left femoral artery. The right femoral artery at the side of the operator was exposed by cut-down exposing the femoral artery and vein then the artery was totally dissected and rubber tapes were used to suspend it proximal and distal to the arteriotomy. A 12F sheath was inserted for the possible insertion of the balloon in cases of emergency to occlude the aorta (If aortic rupture occurs). A guide wire and an angled catheter were advanced (under screen monitor) to the ascending aorta and it stopped short of the aortic valve to avoid the development of arrhythmias (in some cases we withdrew it as PVCs were developed). A pig-tail catheter was used for aortogram during the procedure; before and after deployment. Accurate measurements were performed again for the proper size of the stent (At least 2 different sizes must be available). After proper sizing the endograft was introduced in the right femoral artery via an arteriotomy and it was advanced guided by the radio-opaque marker at the endograft till the proper sealing site and landing zone then the Captiva delivery system deployed the endograft then the balloon was inflated. The balloon then deflated but kept in place then a bi-plane aortogram was done to detect proper deployment and endoleaks (if occurs). The introducer sheath was withdrawn very cautiously. The femoral artery was repaired using prolene 5/0 or 6/0 interrupted stitches and a vacuum drain was inserted. Check of the distal pulses clinically. The left femoral artery was controlled by gentle pressure after removal of the guide wires. No Heparin antidote was given. All the patients were shifted to the CCU and they received double anti-platelet therapy in the same day of the procedure (Aspirin 81mg +Clopidogrel75mg ).

Precautions

■ The landing zones must be at least 20mm away from the aortic injury site.

■ The left subclavian artery was safe to cover or be encroached on by the endograft.

■ Z2 and Z3 were relatively safe areas.

■ The landing zones must be free of calcifications and atherosclerosis.

■ The endograft must oversize the diameter of the aorta by 10% no more.

■ The systolic BP was kept around 100mm Hg. During the procedure the heart rate was around 60/min.

■ The CVP was kept low around 5 or lower.

Technique of the lumbar drainage

All lumbar drain catheters were inserted 24 hours at least before. This was planned as the time lapse between patients’ admission and ordering the endograft in most cases took around 23 hours to be available so had this time enough to insert the catheter and test its drawbacks.

All the operated patients did not receive anticoagulants before the procedure. All of the patients received IV Heparin during the TEVAR insertion keeping the ACT between 200 to 400 seconds by giving low and high dose heparin according to the patients’ condition (the anticoagulation policy was individualized for every case).

The insertion of the catheters were done in the operating theatres under strict aseptic technique with good patients sterilization of the back from the lower chest regions down to below the iliac crest using Alcohol-based chlorhexidine solutions. The operators scrubbed and wear sterilized gowns using sterilized towels, drapes and instruments. After the procedure performed patients were shifted to the CCU and were monitored there waiting for the TEVAR to be performed.

Status

Awake patient; if possible was preferred. This was preferred for the good interaction of the patients minimizing the incidence of nerve trauma and injuries. It allowed also testing of the paresthesia.

Positioning: Sitting position was preferred or the lateral decubitus. We preferred the sitting position whenever possible as it allowed us to do good lumbar flexion and it better localized the midline. This sitting position has an advantage of avoiding the epidural venous plexus which anatomically situated in the para-median position and this avoids the incidence of bleeding.

Level of insertion

At the level of L4-5 or L3-4; this is the level of the iliac crest. Local infiltration anesthesia was injected at the site of the puncture. The sialistic drain is inserted in the puncture needle after the Dura was punctured by wide bore needle and it was advanced to 10-15 cm inside beyond the needle tip. In some cases we advanced it beyond 15 cm and in some other cases we were obliged to withdraw it due to the evolving of paresthesias. The catheters were connected to a transducer and we filled up the system with the patients’ own CSF to avoid the potential infection of priming the transducer with sterile normal saline. No side -ways or flushing systems, no Haparin was used too. The zero level we used was the phlebostatic axis which is the level of the center of the right atrium used to measure the CVP. We used it to measure the CSFP too.

CSF drainage and CSFP monitoring: In all patients we drained from 10 to 15 ml (over one hour) at intermittent periods. The CSFP was kept ideally around 10mm Hg.

The mean perfusion pressure was kept around 60mm Hg. avoiding rise of the CVP. The catheters were removed 72 hours maximum after the procedures.

No infusion of analgesics was used in any of the patients in the lumbar catheter; instead; we used IV Opitaes; IV Naloxone (Opiate antagonist) infused in the subarachnoid space to reduce the incidence of spinal cord ischemia. Somatosensory evoked potentials were monitored during and after the procedure.

Intra-operative neurophysiological monitoring (IONM):

Somatosensory Evoked Potentials (SSEP) and Motor Evoked Potentials (MEP) monitoring during the procedure: We used dual monitoring of the SSEP only without the TcMEP. The SSEP was monitored by applying the cathode electrode over the posterior part of the medial aspect of the ankle, 2cm distal and posterior from the medial malleolus. The anode was attached 2 cm distal to the cathode. This measured the posterior tibial SSEP (we preferred it than the peroneal nerve as it is more accessible). The ground electrode was attached to the calf and it was a band electrode. The used stimulus intensity was 20mA at a rate of 2-10 stimuli/second. The stimulations were alternative in both legs giving separate recordings for both right and left limbs. The positive signs for the good stimulation were the plantar flexion of the big toe or cupping of the sole. We used the multichannel recording system permitted recording of the cortical and subcortical SEPPs. The recording band-pass was 30-1 Hz. The interpretation and the feedback for the recordings were given by the neurologist attended the procedures. The stimulation sites were always kept dry. All the attended team members were informed about the sites of the electrodes and to keep them attached and dray. The used pulses were mono-phasic rectangular pulses of 100-300μS duration and 30-40 milliamper (mA) intensity. This SSEP monitoring assessed the function of the dorsal column and also gave us a thorough idea about the spinal cord functions and we used it also to roughly assess the motor function.

Post procedure investigations

■ CBC.

■ CTA done the second post-operative day.

■ Kidney and liver functions.

■ Lower limb duplex.

■ Thorough neurological assessment.

■ Abdominal ultrasonography.

Results

All the operated patients were middle aged and young males. The age range was 24-57 years old with a mean of 34.7 years old. The patients were presented early after the event of dissection whether it was an RTA or due to hypertension. The range of the time for the diagnosis was 30 to 112 minutes with an average of 55.2 minutes after doing the CTA through the ER. The range of time for the definite treatment and endograft insertion was 16 hours to 39 hours with an average of 28.3 hours. General anesthesia used for all patients. All the RTA patients and the fall from height patient had type B dissection with the inlet intimal tear in all the 4 blunt trauma cases were in Z3 with good landing zones for the endograft and single endograft of 10-15cm length were used with no left subclavian occlusion. None of these cases had any neurological deficit or complications related to the endograft (endoleak, graft migration or graft under-sizing). And no complications related to the lumbar drainage. The catheters for lumbar drainage in those cases were removed the next morning of the procedure. The patient with gas tank explosion had tear and almost transected aorta at T4 and the aorta was covered to T8 with no paraplegia (Table 1).

Gender Males: All cases (100%)
Age Range: 24- 57 years old. Mean 34.7 years
Trauma 6 cases. (14.63 %)
Non-trauma 35 cases. (85.36%)
Type A dissection 25 cases. (60.97 %)
Type B dissection 16 cases. (39 %)
Covered areas beyond zone T8 16 cases. (39 %)
Paraplegia related to distal zones 3 cases beyond T8. (7.31%)
Endografts away from the diaphragm 23cases. (56%)
Endografts approaching or beyond the diaphragm 18 cases. (44%)
Time of diagnosis since hospital admission Range: 30-112minutes. Average: 55.2 minutes
Time of the procedure after admission Range: 16-39 hours.        Average: 28.3 hours
Length of the procedure Range: 135-200 minutes. Average: 160 minutes
Procedure failure 0%
Endoleak 4patients. (9.75%)
Graft migration 0%
De-branching with TEVAR 25cases. (60.97%)
CCU stay Range: 2-17days. Range: 6.9days
Hospital stay Range: 4-27days. Range: 13.2days
General anesthesia All (100%)
Local anesthesia with sedation 0%
Renal failure.
Renal impairment
3patients. (7.31%); 2 recovered.
One patient. (2.43%)
CVS 1patient. (2.43%)
Limb ischemia
Paraplegia
4cases. (9.75%)
3 cases. (7.31%)
Mortality related to the TEVAR procedure One case. (2.43%)

Table 1: Demographic and patients’ data.

Two cases had irregular tortuous aorta and multiple small aneurysms (zones T5 to T11 with small tortuous abdominal aorta). Both had long grafts of 20 cm. Both had smooth procedure with no complications related to the graft but there was minimal CSF leak after the procedure and the patient complained of continuous headache which was positional on the sitting or standing position, there was unexplained nausea and vomiting, tinnitus neck pains and vertigo. These symptoms appeared 2 days after the procedure and treated by reassurance and complete bed rest in the CCU. It recovered totally after 8 days.

In the 27 cases who had acute aortic dissection

There were 19 patients who had a short coverage length of the descending thoracic aorta. The lengths of the used grafts were 10, 15 and 20cm. In all the cases, one endograft only was used. The sealing zones were as follows: In 13cases it was Z1 (covering the left subclavian and the left common carotid). In these cases the left subclavian and the left common carotid were anastomosed to the brachio-cephalic artery. The distal landing zones were between T6 and T8 (8 in T6, 4T7 and one in T8). In all these cases there was no paraplegia or neurological complications. There was only one case who had local infection at the site of the lumbar needle (in the form of severe hyperemia and edema without pus formation, actually it was an inflammation) and it was cured totally. Two patients had mild endoleak and treated conservatively with no complications or further interference. In 6 cases the landing zone was Z2 totally closing the orifice of the left subclavian artery and the pre-procedure plan was to perform left subclavian artery to left common carotid anastomosis(in 5 cases the LSC was easily mobilized and in 2 cases vascular grafts were used). In these 6 cases the distal landing zones were between T5 and T7 in 4 cases and T9 and T11in two cases and one on those two cases had permanent paraplegia despite there was no complications ever related to the lumbar drainage which was smooth with normal SSEPs tracings during the procedure but the paraplegia appeared 6 hours after the procedure (Table 1).

In 8 cases the proximal landing zones were Z3. There was no great vessel covered. The distal landing zones were between T8 and T11. One long graft was used in all the cases (20 cm). There was one case of permanent paraplegia despite the proper monitoring of the SSEPs which were normal during the procedure but the paraplegia developed 3 hours after the procedure. One case had minor uncomplicated endoleak and treated conservatively.

In the 6 cases who had dissecting aortic aneurysms, the landing zones were at Z2in 2 cases with two endografts one was 15cm and the other was 10cm. There was one patient of this category who had permanent paraplegia. One patient died due to major endoleak. The left subclavian was not anastomosed in those two patients as there was extended dissection involving the artery. In the other 4 cases the landing zones were in Z0 in one patient and Z1 in the other 3 patients. The distal landing zones were between T9 and T11. Vascular anastomosis of the great vessels was done in all the cases. One case of those had an ICH and he passed away 9 days after the procedure. Another patient had meningitis which was treated and the patient survived (Table 2).

CSF leak One case. (2.43%)
Local infection One case. (2.43%)
Meningitis One case. (2.43%)
Neuraxial hematoma 0%
Abducens nerve palsy 0%
Symptoamtic ICH One case. (2.43%)
Asymptomatic ICH 0%
Catheter related problems 0%
Mortality related to the lumbar drainage
Mortality related to the TEVAR procedure
One case (2.43%).
One case. (2.43%)

Table 2: Complications related to the lumbar drainage.

The lumbar drainage was done smooth in all cases and tracing of the SSEPs was normal in 40 cases. In one case only there was abnormal tracing and this case had post-procedure paraplegia. The other two cases had paraplegia, were having normal tracing all through the procedure.

There was one case suffered of symptomatic intracranial hemorrhage. He deteriorated with mechanical ventilation for 9 days then he passed away due to ARDS and multi-organ failure. One case had inflammation rather than infection in the lumbar drainage site and he recovered within few days. Another patient had meningitis which was treated and recovered uncomplicated. One case had significant CSF leak which led to severe symptoms and he recovered well within few days.

There were 3 patients who had early permanent paraplegia postprocedure.

Discussion

The TEVAR was first introduced in the mid 1990s. We used the first FDA (2005) approved device in 2007 manufactured by Flagstaff, Ariz. USA. (The W. L. Gore TAG endograft system) [21]. From 2008 till 2017 we used the Medtronic devices more for their availability in our market with no preferences over the other commercially available devices.

The diagnosis was started either in the referring hospitals or in the ER where CTA was done for all the patients proving the primary diagnosis and delineated the whole aorta for the proper plan. The cases were all males and this was mostly due to the more prevalence of hypertension among males in the community of the city and its provinces. The age was low with an average of 34.7 years old compared to other reports having such aortic injuries in 7% only in ages below 40 years [22]. This was due to the intake of some restricted supplements in athletics and improperly treated or ignored hypertension. The trauma cases constituted about 16% of the cases and this might not refer to any epidemiological significance due to the few recorded cases, also other reports did not refer to any significance to this point [22]. The most prevalent injury was type A dissection (61%) while type B was 39% and it was almost the same in some studies with large number of cases [22]. The time to have definite diagnosis was about one hour and the patients managed and stented within 28 hours of admission. Actually this is the standard time in most reports for the TEVAR [23]. The average length of the procedure was 160 minutes which was accepted as regards the instructions of the manufacturing company which is 2-3 hours in un-complicated eventless procedures (www.medtronic.com). The lengths of the grafts and their number were variable according to the extent of the pathology and there must be a plane between the radiologist, the operators and the manufacturing company [24].

The great vessels were dealt with individually also but the general principal we followed was to preserve the left subclavian circulation (revascularize) despite there is controversies regarding this point. As even with covering the LSA the upper limb circulation still preserved with no ischemia. Some put coils, other did not revscularize and most did mandatory revscularization (especially if there was previous LIMA to LAD, functional left arm A-V fistula or dominant left vertebral artery [25-27]. The anastomosis of the brachiocephalic and the left common carotid was a must in cases where their orifices were included in the landing zones. The mortality case due to TEVAR procedure was due to major leak and we did not explore the patient as he passed away in the CCU in less than 30 minutes. And it was due to major bleeding detected by chest tube in the left side.

The complications we met in our cases caused by the lumbar drainage procedure were as follows: (Table 2).

1. CSF leak: There was only one case (2.43%) and he recovered after few cases. Other studies reported an incidence from 0% up to 2.5%.

2. Local inflammation: The incidence was 2.43% while other studies reported an incidence range of 0% to 1.2 % but they included the incidence of both local infection and meningitis together.

3. Meningitis: It was 2.43% in our review.

4. Intracranial hemorrhage (ICH): One case died out of ICH but we could not conclude the exact reason but other reports recorded an incidence of symptomatic ICH of 0% to 5.4% which is a high incidence which by itself condemn the use of lumbar drainage in TEVAR(28,29).

We did not experience neuraxial hematomas, catheter fractures or Abducens palsy in any of the cases. These complications were reported by others. The catheter fractures were between 0% to 1.8%. The Abducens nerve palsy was between 0% and 0.6%. The neuraxial hematoma was between 0% to 3.2%. The asymptomatic ICH was reported to be 0% to 2.9%. The mortality attributed to the lumbar drainage procedure was reported to be 0% to 11% in some series with the most series with large number of cases reporting the mortality between 0% to 1.7% [28,29].

The lumbar drainage was done in all the cases monitoring the CSFP and the SSSEPs. There was no excessive CSF drainage in all the cases and the monitoring of the SSEPs was normal in 40 cases with dumped tracing only in one case. Despite this result, 3 cases were recorded to have permanent paraplegia. The proposed concept of lowering the CSFP (cerbraospinal pressure) will lead to increased CSPP (cerebrospinal perfusion pressure) might be correct in experimental models yet it is not proved in humans that this might prevent the evolving paraplegia when the spinal cord blood supply is decreased [10,29,30]. The control of the CSFP is not exact in all the studies performed before on humans so the results of the effects of the lowering the CSFP on the CSFPP is not accurate; Moreover, the effect of the high CVP on the CSFP may also be a masking factor for the consequent effect of lowering the CSFP on the CSPP(29). The basic injury of the aorta with involvement of the spinal cord vessels by closure due to dissection or thrombosis is reversible in most cases and hence the claimed effect of the lumbar drainage on the spinal cord improving ischemia to our opinion is not there [30,31]. In our study the cases developed paraplegia were those who had extensive pathology and they had long coverage of the descending thoracic aorta approaching the diaphragm and this might explain why they develop it. The reason might be primary occlusion of the spinal cord blood supply in one patient who had abnormal SSEPs and this patient might have occlusion even before the procedure and the paraplegia evolved just after we finished the procedure, so the lumbar drainage did not stop the paraplegia. The other two patients suffered paraplegia also had long aortic coverage to the level of the diaphragm and this to our opinion is the reason for the paraplegia and in fact it was not avoided by the lumbar drainage or lowering the CSFP even below 10mm Hg. The 3 recorded cases of paraplegia were early within few hours after the procedure, just after recovery of anesthesia and they were unavoidable and untreatable. There was no delayed paraplegia despite some other reports recorded delayed paraplegia with TEVAR also as with open surgical repairs. The proposed causes were the impaired spinal blood supply due to thrombosis, systemic hypotension, increased CSFP, cord edema due to reperfusion injury, embolization or hematoma and the proper management according to the cause saved some patients of delayed paraplegia and those patients indeed might benefit the lumbar drainage [32-34].

Even with surgical techniques for aortic injuries and lumbar drainage. There was no definite conclusion about the effect of the lumbar drainage on the outcome regarding paraplegia [35-38].

Conclusions

Despite the easy technique of insertion of the lumbar catheter we had and the recorded incidence of complications which were near to other reports, we do not support its use as it is still a procedure that carries risks, even few but catastrophic. Its value in lowering the incidence of paraplegia was not proved so we do not recommend its use in TEVAR procedures and more broadly speaking, with aortic injuries.

References

Track Your Manuscript

Scheduled supplementary issues

View More »

Media Partners