Anästhesie zur Karotischirurgie

Influence of Anatomic Conditions on Efficacy and Safety of Combined Intermediate Cervical Plexus Block and Perivascular Infiltration of Internal Carotid Artery in Carotid Endarterectomy: A Prospective Observational Trial

Ultrasound-guided intermediate cervical plexus blockade with perivascular infiltration of the carotid artery bifurcation perivacular block (PVB) is a reliable technique for regional anesthesia in carotid endarterectomy (CEA). We investigated the effect of the carotid bifurcation level (CBL) on PVB efficacy and safety in patients undergoing CEA. This prospective observational cohort study included 447 consecutive CEA patients who received PVB over a 6-y period. Vascular and neurologic puncture-related complications were recorded. The CBL was localized at the low level (C4 and C5 vertebra, low-level [LL] group) in 381 (85.2%) patients and at the high level (C2 and C3 vertebra, high-level [HL] group) in 66 (14.8%) patients. Local anesthetic supplementation by surgeons was necessary in 64 (14.3%) patients in the LL group and 38 (59.4%) patients in the HL group (p < 0.001) and was associated with a higher rate of central neurologic complications in the HL group (p = 0.031). Therefore, the efficacy of the PVB may be influenced by the CBL.

[Management of anesthesia in endovascular interventions]

Cardiovascular diseases are one of the leading causes of morbidity and mortality in Germany. In these patients, the high-risk profile necessitates an interdisciplinary and multimodal approach to treatment. Endovascular interventions and vascular surgery have become established as an important element of this strategy in the past; however, the different anatomical localizations of pathological vascular alterations make it necessary to use a wide spectrum of procedural options and methods; therefore, the requirements for management of anesthesia are variable and necessitate a differentiated approach. Endovascular procedures can be carried out with the patient under general or regional anesthesia (RA); however, in the currently available literature there is no evidence for an advantage of RA over general anesthesia regarding morbidity and mortality, although a reduction in pulmonary complications could be found for some endovascular interventions. Epidural and spinal RA procedures should be carefully considered with respect to the risk-benefit ratio and consideration of the recent guidelines on anesthesia against the background of the current study situation and the regular use of therapy with anticoagulants. The following article elucidates the specific characteristics of anesthesia management as exemplified by some selected endovascular interventions.

Combination of high-resolution ultrasound-guided perivascular regional anesthesia of the internal carotid artery and intermediate cervical plexus block for carotid surgery

All previously documented regional anesthesia procedures for carotid artery surgery routinely require additional local infiltration or systemic supplementation with opioids to achieve satisfactory analgesia because of the complex innervation of the surgical site. Here, we report a reliable ultrasound-guided anesthesia method for carotid artery surgery. High-resolution ultrasound-guided regional anesthesia using a 12.5-MHz linear ultrasound transducer was performed in 34 patients undergoing carotid endarterectomy. Anesthesia consisted of perivascular regional anesthesia of the internal carotid artery and intermediate cervical plexus block. The internal carotid artery and the nerves of the superficial cervical plexus were identified, and a needle was placed dorsal to the internal carotid artery and directed cranially to the carotid bifurcation under ultrasound visualization. After careful aspiration, local anesthetic was spread around the internal carotid artery and the carotid bifurcation. In the second step, local anesthetic was injected below the sternocleidomastoid muscle along the previously identified nerves of the intermediate cervical plexus. The necessity for intra-operative supplementation and the conversion rate to general anesthesia were recorded. Ultrasonic visualization of the region of interest was possible in all cases. Needle direction was successful in all cases. Three to five milliliters of 0.5% ropivacaine produced satisfactory spread around the carotid bifurcation. For intermediate cervical plexus block, 10 to 20 mL of 0.5% ropivacaine produced sufficient intra-operative analgesia. Conversion to general anesthesia because of an incomplete block was not necessary. Five cases required additional local infiltration with 1% prilocaine (2-6 mL) by the surgeon. Visualization with high-resolution ultrasound yields safe and accurate performance of the block. Because of the low rate of intra-operative supplementation, we conclude that the described ultrasound-guided perivascular anesthesia technique is effective for carotid artery surgery.

Endarterectomy for asymptomatic carotid artery stenosis under local anaesthesia

BACKGROUND

In this article, we present our experience with such operations performed under local anaesthesia.

METHODS

From January 1997 to November 2007, there were 387 patients operated on for asymptomatic carotid stenosis. Patient data were retrospectively evaluated. Thirty-day neurological morbidity and mortality from six different subgroups were analysed and compared. The numbers of perioperative transient ischaemic attacks, as well as surgical and other perioperative complications were also evaluated.

RESULTS

Overall morbidity and mortality was 1.8% (seven patients). Stroke was noted in 1.3% (five patients). Transitory ischaemic attacks within the first 30 days were observed in 1.6% (six patients). Only those patients who had intraluminal shunt insertion were found to have significantly higher morbidity and mortality. (p = 0.000018). Myocardial infarction was observed in 0.5% (two patients), one fatal.

CONCLUSION

We have achieved acceptable morbidity and mortality rates (1.8%) according to the parameters set by previous studies such as Asymptomatic Carotid Atherosclerosis Study and Asymptomatic Carotid Stenosis Trial as well as American Heart Association and European Stroke Organisation guidelines. All surgeries were done under local anaesthesia. Shunts were inserted in 22 cases (5.68%).