Middle cerebral artery blood velocity, embolisation, and neurological outcome during carotid endarterectomy: a prospective comparison of the Javid and the Pruitt-Inahara shunts

Tumor ablation including carotid artery resection and simultaneous reconstruction: A retrospective study

The study purpose is to review the surgical approach and evaluate the results in cases of head and neck malignancies with internal carotid artery invasion. The anatomical site of the primary tumor varied including a fixed massive metastatic neck disease of an occult intraoral carcinoma of the right tonsil, a recurrent metastatic neck tumor after laryngectomy for glottic primary carcinoma and a metastatic malignant melanoma of an unknown primary origin. In all cases carotid artery was invaded and therefore resected. An extended Javid shunt was performed between common carotid artery (CCA) and internal carotid artery (ICA) followed by CCA grafting with an interposition saphenous vein graft. In one case the vagus nerve was also grafted with an interposition sural graft. The total patient number was three. By clinical examination, follow-up and duplex scanning, the patency of the carotid grafts, vascular and non-vascular complications, disease recurrence and survival were analysed. Additionally, there was a double metachronous reconstruction for recurrence, giving the opportunity to study the graft adoption and response to disease. Internal carotid artery invasion portends a poor prognosis. The results show that carotid artery resection followed by the appropriate reconstruction yields a chance for cure or can provide reasonable palliation.

Shunt intention during carotid endarterectomy in the early symptomatic period and perioperative stroke risk

OBJECTIVE

Whether recent stroke mandates planned shunting during carotid endarterectomy (CEA) is controversial. Our goal was to determine associations of various shunting practices with postoperative outcomes of CEAs performed after acute stroke.

METHODS

The Vascular Quality Initiative database (2010-2018) was queried for CEAs performed within 14 days of an ipsilateral stroke. Surgeons who prospectively planned to shunt either shunted routinely per their usual practice or shunted selectively for preoperative indications. Surgeons who prospectively planned not to shunt either shunted selectively for intraoperative indications or did not shunt. Univariable and multivariable analyses compared shunting approaches.

RESULTS

There were 5683 CEAs performed after acute ipsilateral stroke. Surgeons planned to shunt in 56.1% of cases. Patients whose surgeons planned to shunt vs planned not to shunt were more likely to have severe contralateral stenosis (8.8% vs 6.9%; P = .008), to receive general anesthesia (97.5% vs 89.1%; P < .001), and to undergo conventional CEA (94% vs 81.8%; P < .001). Unadjusted outcomes were similar between the cohorts for operative duration (124.3 ± 48.1 minutes vs 123.6 ± 47 minutes; P = .572) and 30-day stroke (3.4% vs 3%; P = .457), myocardial infarction (1.1% vs 0.8%; P = .16), and mortality (1.6% vs 1.3%; P = .28). On multivariable analysis, planning to shunt vs planning not to shunt was associated with similar risk of 30-day stroke (odds ratio [OR], 1.17; 95% confidence interval [CI], 0.82-1.67; P = .402). On subgroup analysis, in 38.4% patients, no shunt was placed, whereas the remainder received routine shunts (44.4%), preoperatively indicated shunts (11.6%), and intraoperatively indicated shunts (5.5%). Compared with no shunting, shunting by surgeons who routinely shunt was associated with a similar stroke risk (OR, 1.39; 95% CI, 0.91-2.13; P = .129), but shunting by surgeons who selectively shunt on the basis of preoperative indications (OR, 2.11; 95% CI, 1.22-3.63; P = .007) or intraoperative indications (OR, 3.34; 95% CI, 1.86-6.01; P < .001) was associated with increased stroke risk. Prior coronary revascularization independently predicted increased intraoperatively indicated shunting (OR, 1.37; 95% CI, 1.05-1.8; P = .022).

CONCLUSIONS

In CEAs performed after acute ipsilateral stroke, there is no difference in postoperative stroke risk when surgeons prospectively plan to shunt or not to shunt. Shunting is often not necessary; however, when shunting is performed, routine shunters achieve better outcomes.

Flow Analysis in Vascular Shunts that Bypass the Carotid Artery

When blood flow through a carotid artery is impaired and vascular surgery is necessary to restore adequate circulation a vascular shunt can be applied to maintain cerebral blood flow. Several vascular shunts are commercially available, but there is only limited test data on their flow capacity. The purpose of this study is to determine the flow capacity of three vascular shunt systems. A theoretical model has been developed for this purpose. To validate the model, in vitro flow measurements were taken. Application of the model showed that all shunts cause a decrease in blood flow. The amount of flow decrease varied widely from 13% (Javid shunt) to 55% (Pruitt-Inahara). In vitro measurements confirmed the validity of the model.

In conclusion, it is important for the vascular surgeon to realise that vascular shunts show large differences in flow capacity. Of the three investigated shunts, the Javid has the highest flow capacity.

Temporary vascular shunt for damage control of extremity vascular injury: A toolbox for trauma surgeons

In an emergency, a general surgeon may be faced with the need to treat arterial trauma of the extremities when specialized vascular surgery is not available in their hospital setting, either because an arterial lesion was not diagnosed during pre-admission triage, or because of iatrogenic arterial injury. The need for urgent control of hemorrhage and limb ischemia may contra-indicate immediate transfer to a hospital with a specialized vascular surgery service. For a non-specialized surgeon, hemostasis and revascularization rely largely on damage control techniques and the use of temporary vascular shunts (TVS). Insertion of a TVS is indicated for vascular injuries involving the proximal portion of extremity vessels, while hemorrhage from distal arterial injuries can be treated with simple arterial ligature. Proximal and distal control of the injured vessel must be obtained, followed by proximal and distal Fogarty catheter thrombectomy and lavage with heparinized saline. The diameter of the TVS should be closely approximated to that of the artery; use of an oversized TVS may result in intimal tears. Systematic performance of decompressive fasciotomy is recommended in order to prevent compartment syndrome. In the immediate postoperative period, the need for systematic use of anticoagulant or anti-aggregant medications has not been demonstrated. The patient should be transferred to a specialized center for vascular surgery as soon as possible. The interval before definitive revascularization depends on the overall condition of the patient. The long-term limb conservation results after placement of a TVS are identical to those obtained when initial revascularization is performed.

Concomitant Vascular War Trauma Saturating a French Forward Surgical Team Deployed to Support the Victims of the Syrian War (2013). Interest of the Vascular Damage Control

Vascular injuries from war require an emergency treatment whose objective is to quickly obtain hemostasis and the restoration of arterial flow. In this context of heavy trauma and limited means, damage control surgery is recommended and is based on the use of temporary vascular shunts (TVSs). We report the management of the simultaneous arrival of 2 vascular injuries of war in a field hospital. Patient 1 presented a ballistic trauma of the elbow with a section of the humeral artery (Gustillo IIIC). A TVS was set up during the external fixation of the elbow. Final revascularization was carried out and aponevrotomies of the forearm were performed. Patient 2 had a riddled knee with an open fracture of the femur, an avulsion of the popliteal artery, and a hemorrhagic shock. A strategy of damage control surgery was carried out with placing an arterial and venous shunt. Aponevrotomies of the leg were carried out before casting. For the traumatisms of the arteries of the members, the use of shunts is reserved for the lesions of the proximal vessels. Many vascular shunts available have the same performances to restore the arterial flow and prevent secondary thrombosis. The time before the final revascularization depends on the clinical condition of the patient. The value of anticoagulation in these cases was not shown.

Routine or selective carotid artery shunting for carotid endarterectomy (and different methods of monitoring in selective shunting)

BACKGROUND

Temporary interruption of cerebral blood flow during carotid endarterectomy can be avoided by using a shunt across the clamped section of the carotid artery. This may improve outcome. This is an update of a Cochrane review originally published in 1996 and previously updated in 2009.

OBJECTIVES

To assess the effect of routine versus selective or no shunting during carotid endarterectomy, and to assess the best method for selecting people for shunting.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (last searched August 2013), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2013, Issue 8), MEDLINE (1966 to August 2013), EMBASE (1980 to August 2013) and Index to Scientific and Technical Proceedings (1980 to August 2013). We handsearched journals and conference proceedings, checked reference lists, and contacted experts in the field.

SELECTION CRITERIA

Randomised and quasi-randomised trials of routine shunting compared with no shunting or selective shunting, and trials that compared different shunting policies in people undergoing carotid endarterectomy.

DATA COLLECTION AND ANALYSIS

Three review authors independently performed the searches and applied the inclusion criteria. For this update, we identified two new relevant randomised controlled trials.

MAIN RESULTS

We included six trials involving 1270 participants in the review: three trials involving 686 participants compared routine shunting with no shunting, one trial involving 200 participants compared routine shunting with selective shunting, one trial involving 253 participants compared selective shunting with and without near-infrared refractory spectroscopy monitoring, and the other trial involving 131 participants compared shunting with a combination of electroencephalographic and carotid pressure measurement with shunting by carotid pressure measurement alone. In general, reporting of methodology in the included studies was poor. For most studies, the blinding of outcome assessors and the report of prespecified outcomes were unclear. For routine versus no shunting, there was no significant difference in the rate of all stroke, ipsilateral stroke or death up to 30 days after surgery, although data were limited. No significant difference was found between the groups in terms of postoperative neurological deficit between selective shunting with and without near-infrared refractory spectroscopy monitoring, However, this analysis was inadequately powered to reliably detect the effect. There was no significant difference between the risk of ipsilateral stroke in participants selected for shunting with the combination of electroencephalographic and carotid pressure assessment compared with pressure assessment alone, although again the data were limited.

AUTHORS' CONCLUSIONS

This review concluded that the data available were too limited to either support or refute the use of routine or selective shunting in carotid endarterectomy. Large scale randomised trials of routine shunting versus selective shunting are required. No method of monitoring in selective shunting has been shown to produce better outcomes.

Comparison of internal shunts during carotid endarterectomy under routine shunting policy

We compared patients who underwent carotid endarterectomy (CEA) using two-way and three-way internal shunts and discussed which shunt was more appropriate and effective for surgeons. Eighty-two patients (mean 69.5 ± 6.1 years old, mean degrees of stenosis 79.6 ± 10.4%) who had undergone CEA by our routine shunting policy were examined concerning the difference of Sundt and Pruitt-Inahara (P-I) shunts in clinical use. Carotid clamping time for the P-I shunt was over 2 minutes longer than that by Sundt in either split or conventional continuous arteriotomy (p < 0.001). The proportions of cases with multiple trials of either arteriotomy or insertion of a shunt tube, cases detected more than one high-intensity spot on diffusion-weighted images of magnetic resonance imaging after CEA, and cases detected postoperative intimal flaps detected by multi-detector CT angiography showed no significant differences between the two shunt groups. The two-way Sundt shunt was quicker than the three-way P-I shunt in placement with no remarkable problems. Split arteriotomy was not useful in shortening the placement time for either Sundt or P-I shunt tubes, compared with continuous arteriotomy. A simple two-way shunt with easy handling like the Sundt shunt would be also appropriate to choose in selective shunting under the unfamiliarity of treating shunts.

Technical options for the treatment of extracranial carotid aneurysms

Extracranial carotid artery aneurysm (ECAA) is an uncommon but serious condition. The morbidity and mortality of ECAA are assumed to be high when untreated. ECAA treatment presents a challenge because of accessibility of the carotid artery and lack of evidence-based guidelines. When exclusion of the aneurysm is considered, surgical resection of the aneurysm with reconstruction of blood flow is still considered the gold standard. Several alternative and endovascular approaches are discussed.

Usage of external shunt in hybrid approach for aortic arch aneurysm to restore cerebral oxygenation

A hybrid approach, combining open and endovascular procedures, may be a less invasive substitute to correct aortic arch pathologies in high-risk patients. We describe an 82-year-old male patient with an atherosclerotic aortic arch aneurysm, which was treated with proximal transposition of all arch branches and endovascular aortic arch repair. During the left common carotid artery reconstruction, oxygen saturation level of the left cerebral hemisphere decreased lower than the safety limit. To re-establish brain perfusion, we installed an external shunt from the right common femoral artery to the left common carotid artery. The oxygen saturation was restored to an acceptably safe level, and the patient tolerated the procedure without any signs of postoperative ischemic stroke.

Temporary intravascular shunts used as a damage control surgery adjunct in complex vascular injury: collective review

In this systemic review, we summarise the types, configurations, durations, indications and complications of the temporary intravascular shunts used as an adjunct of damage control surgery (DCS) in severe vascular injuries. We conclude that temporary intravascular shunts can be used without systemic anticoagulation for a prolonged time to maintain distal perfusion in combined orthopaedic and vascular injuries, in the setting of DCS and transferring.

Prevention of postoperative wound haematomas and hyperperfusion following carotid endarterectomy

OBJECTIVE

To study the incidence of wound haematomas and hyperperfusion following carotid endarterectomy and the effect of changes in perioperative management.

METHODS

We undertook a prospective audit of the postoperative outcome of 300 consecutive carotid endarterectomies performed for a symptomatic stenosis of the internal carotid artery, under the care of a single consultant.

RESULTS

audit of the first 100 operations between 1990-93 resulted in 4 changes to clinical practice. These included the use of Dacron instead of vein because of 3 vein patch blowouts, invasive postoperative monitoring of blood pressure, and the use of intravenous beta-blockers to control hypertension, because of 4 hyperperfusion injuries. The use of 10F suction drains was discontinued, because they did not prevent 8 wound haematomas. The results of the second 100 cases between 1994-97 and the third 100 cases between 1998-2000 confirmed no further hyperperfusion injuries or patch blowouts (p =0.01 and 0.04 respectively). Larger 14F suction drains were reintroduced for the third series because of thirteen haematomas in the second series (p =0.09). Only 4 haematomas occurred in the third series ( p =0.05). The need for beta-blockers fell in the third series due to the introduction of local anaesthesia (p =0.0001).

CONCLUSION

The use of Dacron patches and postoperative control of hypertension has reduced the incidence of haemorrhage and hyperperfusion after carotid endarterectomy. Larger suction drains may also help.

The Pruitt-Inahara shunt maintains mean middle cerebral artery velocities within 10% of preoperative values during carotid endarterectomy

OBJECTIVE

The purpose of this study was to assess the ability of the Pruitt-Inahara shunt to maintain adequate middle cerebral artery velocities during carotid endarterectomy.

STUDY DESIGN

Prospectively collected data recorded during 548 carotid endarterectomies performed at a single university hospital were analyzed to look at changes in cerebral blood flow velocities at different stages during the procedure. Parallel data relating to blood pressure and end-tidal carbon dioxide were also examined.

RESULTS

During the first carotid artery cross clamp, middle cerebral artery velocity fell by 42%. A total of 169 patients (31%) had velocities that fell below 15 cm/s (electrical activity in the brain becomes altered below this level). After shunt insertion, only 2% of patients had middle cerebral artery velocities less than 15 cm/s. In only one patient was the velocity less than 10 cm/s. Increased systolic or diastolic blood pressure raised flow through the shunt significantly (P =.001). When two criteria used for selective shunt use were compared, only a moderate correlation was found between absolute middle cerebral artery velocity after carotid cross clamping and percentage change in middle cerebral artery velocity relative to preclamp values.

CONCLUSIONS

The Pruitt-Inahara shunt is able to maintain adequate middle cerebral artery velocity in 98% of patients undergoing carotid endarterectomy. Alterations in blood pressure can significantly affect flow through the shunt.