As an NLM library, it provides access to scientific literature. Inclusion in the NLM database does not imply endorsement or approval of the content by NLM or the National Institutes of Health.
Learn more:PMC disclaimer|PMC copyright notice
Korean Anesthesia J.2018 august 71 sek. 4): 274-288.
Published online July 4, 2018. doi:10.4097/kja.d.18.00143
Author information Article notes Copyright and License Information PMC disclaimer
Cervical plexus blocks (CPBs) are used in various head and neck surgeries to provide adequate anesthesia and/or analgesia. However, the block is performed in a narrow space in the neck area that contains many delicate structures, many layers of fascia and complex innervation. Since intermediate CPBs were introduced in 2004 in addition to superficial and deep CPBs, there has been some confusion regarding the nomenclature and definition of CPBs, particularly intermediate CPBs. In addition, CPB can be performed more safely and accurately under ultrasound guidance with the increasing role of head and neck ultrasound. In this review, the authors will describe methods including ultrasound techniques and clinical applications of conventional deep and superficial CPB. In addition, the authors will discuss controversial issues regarding indirect CPBs, including nomenclature and related potential side effects, which can often be neglected by focusing on the anatomy of the cervical fascia and cervical plexus layers. Finally, the authors will try to improve the classification of CPB methods based on target areas that can be easily identified under ultrasound guidance, taking into account the results of each CPB method.
Keyword:Airway obstruction, cervical fascia, cervical plexus, cervical plexus obstruction, phrenic nerve palsy, ultrasound
Cervical plexus block (CPB) provides effective anesthesia and analgesia of the head and neck region [1-7]. the most common clinical application of CPB was carotid endarterectomy (CEA) [8–12]. Traditionally, CPB is classified as deep and superficial , ale w 2004 r. Telford i Stoneham  proposed an indirect CPB involving sub-study fascial injection in addition to superficial and deep CPB based on a cadaver study by Pandit et al.  And 2010, Choquet et al.  attempted to improve the concept of CPB intermediates using ultrasound technology. However, the terms "superficial", "intermediate" and "deep" are ill-defined anatomical terms that only indicate the topographic position of the tissue relative to the skin. Therefore, there has been some confusion in the nomenclature and definition of CPB, especially intermediate CPBs.
With the increasing role of ultrasound in the head and neck region, CPB can be performed more safely and accurately under ultrasound guidance, allowing for easy localization of various important landmarks, including muscles, cervical vertebrae, great vessels, nerves, and the cervical region. fascia [17In particular, an understanding of the detailed configuration of the cervical fascia is essential for success with CPB, as some cervical fascia are known to play an important role in the diffusion of local anesthetic solution [15,18–20]. However, the structural features of the cervical fascia have not been fully explored for regional anesthesia. In addition, there was disagreement about the exact identification of the deep cervical fascia, especially in the lateral cervical region [21–24], and there are also anatomical differences .20,25]
Accordingly, this review first describes the anatomy of the cervical fascia and cervical plexus layers, then the methods of performing CPB including ultrasound techniques, then the results of conventional deep and superficial CPB, and a related new but controversial CPB intermediate. In addition, this review will discuss the potential adverse effects of CPB, which are often overlooked, and finally attempt to improve the classification of CPB methods based on target areas easily identifiable under ultrasound guidance, taking into account effects and potential adverse effects for each CPB method.
Examination of the cervical fascia layers is clinically important for predicting disease spread [26-28], optimizing surgical treatment29] and conduction of regional anesthesia in the neck area [15, 18-20] and changes in the cervical fascia may play an important role in the pathogenesis of chronic neck pain [15, 18-20].30,31] However, descriptions of fascial alignment and definitions of fascial spaces in the neck region are inconsistent and unclear, and terminology varies. According to the 41st issue of Gray's Anatomy , fascia is described as "sheaths, sheets, or other masses of connective tissue large enough to be visible to the naked eye," and the Fascia Nomenclature Committee for the Fascia Research Conference describes it as "sheaths, sheets, or other removable aggregates of connective tissue , which form under the skin to attach, trap and separate muscles and other internal organs"  However, the structural classification of the cervical fascia has been controversial despite the use of newer techniques and materials to preserve and study the structure of the fascia. Like Grodinsky and Holyoke  described in their pioneering study based on an autopsy in 1938, the inherent difficulties in dissecting the cervical fasciae spaces and their apparently artificial clustering may cause confusion in the description of the cervical fascia and discrepancies between different authors. According to a recent work by Guidery et al. , the cervical fascia can be classified as superficial and deep, although instead of using the term "superficial cervical fascia", the more specific term "subcutaneous tissue" has been suggested to avoid confusion with its superficial deep cervical fascia  The deep cervical fascia can be divided into three layers : (a) the superficial layer, also called ependymal fascia, but now referred to as masseter fascia, submandibular fascia, or sternocleidomastoid fascia (SCM) - trapezius fascia, although it has been argued that the SCM-trapezius fascia between the SCM and the trapezius muscle is incomplete [21,22]; (b) the middle layer, which is proposed to be called the cingulate fascia or the visceral fascia, and (c) the deep layer, which is proposed to be called the paravertebral fascia instead of the prevertebral fascia, because the term "pre-spinal fascia " should only be used in the front part. The carotid space, containing the great vessels, deep cervical lymph nodes, and nerves, is a very important structure that can be damaged during CPB and is commonly referred to as the "carotid sheath and contents"  According to the literature [37,38], the carotid sheath is a distinct histological structure distinct from the other fascial layers, and the common carotid sheath varies in thickness between individuals and/or by location. However, there is disagreement as to whether the cervical sheath consists of all three layers of the deep cervical fascia and only the deep or superficial layer of the deep cervical fascia, or whether there is no proven fascial layer at all  Palliyalil i in.  reported that the carotid sheath is a strong fibroelastic tissue barrier that protects the contents from saliva and local infections after neck surgery, but local anesthetics appear to penetrate the carotid sheath Grave. 1shows a schematic drawing of the cervical fascia as Guidera et al.  suggested.
The cervical plexus lies in the sulcus between the long head and the median, beneath the prevertebral fascia, but not in the intersphenoidal sulcus because the anterior scalene is almost absent cranially near the C4 and C3 levels.42] Two neural loops, formed at the junction of adjacent anterior spinal nerves C2 to C4, give off four superficial sensory branches, arranged in craniocaudal order as follows: minor occipital (C2, C3), major auricular (C2, C3), nerves transverse cervical (C2, C3) and supraclavicular (C3, C4). They first run backwards and soon pierce the prevertebral fascia. They then pass through the interfascial space between the SCM and the prespinal muscles before reaching the skin and superficial structures of the neck via the nerve point of the SCM muscle [43,44] Thus, the superficial branches of the cervical plexus cover a relatively large distance from the paravertebral space to their respective superficial endpoints, including the skin and subcutaneous tissue of the neck and back of the head and shoulders.45,46] Instead, fibers from the superior (C1-C2) and inferior (C2-C3) roots join at the level of the medial scapulohyoid tendon to form a loop, the ansa cervicalis.47] Ansa cervicalis is known to supply the motor branches of hypothyroidism and the muscles of the SCM  with a high degree of diversification of origin and distribution ; However, the ansa cervicalis is suspected of having an afferent neuronal complex  The anterior ridge of C3 and C4 forms a loop, and the branches of this loop join at C5 to form the phrenic nerve. The cervical plexus is known to anastomose with the accessory spinal nerve, the hypoglossal nerve, the facial nerve, the vagus nerve, the glossopharyngeal nerve, and the sympathetic trunk.43,49,51]Grave. 2shows a schematic drawing of the deep and superficial cervical plexuses.
Schematic drawing of the deep cervical plexus and the superficial cervical plexus. (A) The four superficial branches of the cervical plexus are shown in yellow, and the deep branches of the cervical plexus (ansa cervicalis) are shown in green. The cervical plexus is known to anastomose with many cranial nerves and the sympathetic trunk. (B) The superficial cervical plexus arises behind the posterior margin of the SCM (stereocleidomastoid) muscle and innervates the head, neck, and shoulder regions. Illustration taken from Restrepo et al. 
Cervical plexus blockade methods
CPB can be performed at a deep, superficial, or intermediate level, although these terms are not well defined.
Deep cervical plexus block
Deep CPB is described as a paravertebral block targeting the C2-C4 spinal nerves [13,53], which can be achieved with a single injection or three separate injections [13,53,54] Deep CPB performed in the paravertebral space can block not only the superficial branches but also the deep branches of the cervical plexus, causing relaxation of the neck muscles, although this has not been shown to be clinically significant.10,14,55] Furthermore, if the ansa cervicalis also has a complex of afferent neurons , deep CPB would be of greater clinical relevance in the treatment of postoperative pain after neck surgery involving hypothyroidism and/or SCM muscles or pain originating from the neck. Wan et al.  oraz Goldberg i in.  reported that deep CPBs in the transverse process of C2 or C3 can effectively treat cervicogenic headache. Deep CPB has also been used during thyroid or parathyroid surgery [58,59], oral and maxillofacial surgery  and CEA [60–64] for adequate anesthesia and/or analgesia. Deep CPB can cause serious complications such as intravascular injection, epidural or spinal injection, and phrenic nerve palsy due to the deep endpoint.12,65]; However, with the introduction of ultrasound, deep CPB has become a relatively safe and simple procedure [3,42,66,67] For ultrasound-guided deep CPB, Perisanidis et al.  and Saranteas et al.  simply injected local anesthetic into the space between the prevertebral fascia and the transverse process of the cervix under ultrasound guidance, but Wan et al.  and Sandeman et al.  injected local anesthetic after the needle touches the transverse process of the target cervix under ultrasound guidance.
Superficial cervical plexus block
Superficial CPB has traditionally been described as a subcutaneous injection technique performed in the medial posterior margin of the SCM muscle, targeting the superficial branches of the cervical plexus.12,13] This conventional subcutaneous infiltration technique for superficial CPB can be performed using an ultrasound-guided technique , and depending on the type of head and neck surgery, it is also possible to selectively block one or more superficial branches of the cervical plexus using landmarks [1,4,69,70] or ultrasound technique [71-74]. It is known that superficial CPB, in contrast to deep CPB, is associated with a low risk of complications and is easy to manage [12,59,75] During superficial CPB, however, it is important that the needle tip be placed in the subcutaneous tissue to avoid the unwanted effects of a deep block.76,77] Unilateral or bilateral superficial CPB can be used as postoperative analgesia after various head and neck surgeries, such as thyroidectomy.1,78,79], minimally invasive parathyroidectomy , tympanomastoid surgeon , anterior discectomy and cervical fusion  and hypogastric and occipital craniotomy  Can also be used as a single anesthetic method during external ear surgery  Superficial CPB can also be used as a supportive block in shoulder, clavicle, chest, and upper chest wall surgeries, especially in cases of supraclavicular branch occlusion. At Ajou University Hospital, we use a landmark based superficial CPB for various treatments on the head, neck and upper chest wall, both in children and adults, to achieve anesthesia and/or analgesia (Grave. 3).
Breakthrough superficial cervical plexus blocks were performed at Ajou University Hospital for ear, neck, and upper chest surgery to achieve adequate anesthesia and/or analgesia. (A) A 77-year-old man undergoing resection of a turbinate hemangioma underwent block of the great auricular and inferior occipital nerves. (B) Selective supraclavicular nerve block was performed in a 4-year-old girl undergoing resection of a congenital melanocytic nevus in the right upper chest wall. (C) A 94-year-old female patient undergoing resection of squamous cell carcinoma in the right cervical region underwent a major cervical and transverse cervical nerve block. (D) A 52-year-old man undergoing incision and drainage of a right upper chest wall abscess underwent a selective supraclavicular nerve block. To avoid a deep puncture, the needle was slightly bent.
Intermediate cervical plexus block
In 2002, Zhang and Lee  reported that there is no layer lining the deep fascia in the space between the SCM and the trapezius muscle, in an area called the posterior cervical triangle  They performed a cross-sectional anatomical study using epoxy sheet lamination on cadavers, but their results are still controversial [24,35,36] Interestingly enough, in the 41st issue of Gray's Anatomy  described that the investing fascia between the SCM and the trapezius muscle is formed by sparse tissue indistinguishable from the superficial cervical fascia. However, in 2003, Pandit et al.  introduced a new concept of the subinvestor fascia injection technique (superficial to the prevertebral fascia but below the investor fascia) as a superficial CPB method. In this study, Pandit et al.  hypothesized that there is communication between the superficial and the deep spaces via the prevertebral fascia, which may explain why the effectiveness of superficial CPB is comparable to that of deep CPB and combined deep and superficial CPB during CEA [10,62] W 2004 r. Telford i Stoneham  expected that this intermediate CPB could also provide the same results as deep CPB while avoiding some of the practical difficulties associated with deep CPB. However, this would be possible if communication via the prevertebral fascia existed. In 2007, Pandit et al.  expressly stated that an intermediate block is one in which the injection needle penetrates the ependymal fascia of the neck, deep in the subcutaneous layer but superficial to the prespinal fascia. In this context, the permeable nature of the prevertebral fascia should be an important consideration, as it may ultimately determine the characteristics of interstitial CPB. However, several papers [7,9,83–85] have already been published based on Pandit's hypothesis  that injection of indirect CPB can spread to deep tissue through the prevertebral fascia, and thus indirect CPB may have similar effects to deep CPB, although no clinical trials have been conducted to test the penetrating nature of the prevertebral fascia.
Technique and nomenclature
Research by Barone et al. , Ramachandran i in.  and Merdad et al.  used a blind approach to indirect CPB, targeting the space between the fascial lining and the prespinal fascia using landmarks and loss of resistance or the pop technique, although Merdad et al.  used the term “superficial” CPB instead of “intermediate” CPB. However, it was probably not easy even for very experienced specialists to place the needle tip exactly in the desired space without the help of ultrasound. Because Kefalianakis et al.  published the first report of CPB ultrasound targeting the space between the SCM and the anterior stapes muscles for CEA in 2005. CPB ultrasound has grown in popularity because it can be performed safely and precisely in the target area  And 2010, Choquet et al.  argued that an intermediate CPB should target the posterior cervical space (PCS) at the C4 level. PCS described by Choquet et al.  is the interfascial space between the SCM and the prespinal muscles that can be seen on cross-sectional imaging. They used an ultrasound technique and argued that the PCS corresponded to the subfascial space described by Pandit et al.  The superficial branches of the cervical plexus, coming from the deep tissue, pass through this space after piercing the prevertebral fascia, leaving the skin and the superficial tissue through the posterior edge of the SCM muscle 
Fordi Choquet et al.  introduced indirect CPB using the ultrasound technique, many studies were published under the name ultrasound indirect CPB [3,9,11,63,84,85,88–95] In these studies, the authors performed a posterior or anterior approach to achieve an indirect CPB to provide anesthesia and/or analgesia for CEA [63,84,92-95], operations involving the SCM muscle [90,91] and diverticulum of cervical esophagus  under ultrasound guidance. For posterior ultrasound access for indirect CPBs, after the target level of the cervical spine with elevation from the C7 vertebra has been determined by ultrasound, the SCM and soleus medius are placed in the center of the screen. At this point, the needle is inserted into the PCS (the space between the SCM and the prespinal muscles) in a lateral to medial direction (plane technique), using the anterior edge of the medial stapes as a reference point for needle tip placement. The local anesthetic is then injected slowly and carefully while watching the spread of the anesthetic in the PCS [90,91] Anterior approach for indirect CPB US can provide similar results to other peripheral techniques for CEA  According to Leblanc et al. , indirect CPB ultrasound is easy to perform, safe and reliable. On the other hand, some authors [96–99] performed an indirect CPB ultrasound in PCS but referred to it as a superficial CPB ultrasound. In a review of block anesthesia for CEA by Stoneham et al. , CPB is described as five techniques: superficial, deep, superficial US, deep US and indirect CPB US. In this review, Stoneham et al.  described CPB superficial ultrasound as a method of inserting a needle block adjacent to the cervical plexus under the prevertebral fascia. However, if the locking pin penetrates the prevertebral fascia, it is no longer classified as indirect CPB as argued by Telford and Stoneham,  and Pandit et al. [12,15] originally proposed, nor the classical CPB surface. Therefore, the use of the term "superficial" is not appropriate in this case.
The reason for the above discrepancies in the nomenclature of CPB methods seems to be the location of the block and the blocked branch of the cervical plexus. CPB performed in the cervical paravertebral space (C2-C4) can simultaneously block both the superficial and deep branches of the cervical plexus , although we call it deep rather than surface CPB given the position where the block is executed. Thus, the nomenclature for the CPB technique performed in PCS, resulting in spread of the local anesthetic, would more appropriately be called indirect CPB than superficial CPB, even though indirect and superficial CPB target essentially the same superficial branches of the cervical plexus.
Impact on the intermediate cervical plexus
Importantly, interstitial CPBs may provide different anesthetic and analgesic effects compared to superficial CPBs. The cervical plexus (C2–C4) is known to provide sensory innervation to the SCM muscle, including proprioception, via variable anastomosis with the accessory spinal nerve.43,100–104] Therefore, the SCM muscle appears to have complex innervation, but it is known that the cervical branches of the nerve supplying the SCM muscle, after piercing the prevertebral fascia, anastomose with the accessory spinal nerve on the posterior surface or inside The SCM muscle [100,101,105] Although it is known that the accessory spinal nerve itself also has a sensory function [52,106,107], it is believed that the cervical plexus (ansa cervicalis) is another, next to the accessory spinal nerve, another source of motor innervation of the SCM muscle [48, 52, 108-110]. Therefore, it is possible that indirect CPB ultrasound, accurately performed in the PCS at a specific level of the cervical vertebrae, can exclude all four cutaneous branches of the cervical plexus and the sensory-motor branches of the cervical plexus that also supply the SCM muscle, providing adequate anesthesia and analgesia for manipulative procedures.90] or SCM muscle resection  Likewise Jerzingacy  suggested applying local anesthesia directly to the SCM muscle to block the sensory branches of the cervical plexus that innervate the SCM muscle during local anesthesia before thyroidectomy. According to Senapathi et al. , indirect CPB ultrasound is more effective than the multidirectional subcutaneous injection technique of superficial CPB in reducing pain after thyroidectomy, although the authors used the term “surface CPB ultrasound” instead of indirect CPB ultrasound. In addition, pain associated with the SCM muscle, similar to the SCM syndrome  or pain associated with trigger points in the SCM muscle [113–115] can theoretically be treated with this technique. At the University Hospital of Ajou, children and adults routinely have a posterior access, if necessary, an indirect CPB ultrasound, targeting the C4-C5 PCS (Grave. 4). In contrast, classical superficial CPB performed subcutaneously would not produce such indirect blocking effects. Therefore, although it is currently unclear whether the trapezoidal fascia of the SCM is present in the posterior cervical triangle, it would be reasonable to define superficial CPB as a multidirectional or single subcutaneous injection technique targeting one or more superficial branches of the cervical plexus, regardless of the use of ultrasound technology. In addition, although both superficial and indirect CPBs essentially target the same superficial branches of the cervical plexus, indirect CPBs may cause some adverse effects that superficial CPBs do not.
Posterior approach ultrasound image of a C4-5 IPC block in a 3-year-old patient with torticollis undergoing unipolar sternocleidomastoid release (SCM) with myectomy. Using local anesthesia, a hydrotomy of the posterior cervical space between the SCM muscle and the prevertebral fascia is observed, and a local anesthetic is distributed around the carotid sheath. CA: carotid artery, IJV: internal jugular vein, LA: local anesthetic. White arrows indicate: prevertebral fascia.
Carotid plexus block and carotid endarterectomy
The most common clinical use of CPB was CEA. CEA is a validated intervention for stroke prevention associated with symptomatic carotid artery stenosis [116,117], which includes incisions in the skin, platypus muscle, carotid artery, and carotid artery. Since the first CPB report for CEA  in 1988, various techniques for using CPB were evaluated in CEA, although the ideal anesthetic technique for CEA remains a matter of debate.54,119–121] Stonehama i in.  in 1998 and Pandit et al.  reported in 2000 that superficial CPB is as effective for CEA as deep or combined deep and superficial CPB. However, during CEA for CPB, the surgeon will often perform subcutaneous or deep local anesthesia, regardless of the type of CPB method.74,94,122], probably because within the structures of the neck, including the cervical sheath, there are some areas innervated by cranial nerves that are not reached even by deep CPB [8,51,94,123–125] or cutting pain near the midline, possibly caused by opposing fibers,8,74,123,126] Seidel i in.  showed stable anastomosis of the cervical branch of the facial nerve with the transverse cervical nerve of the cervical plexus. The pain associated with the incision of the cervix during CEA was completely relieved with lidocaine spray.124Cranial nerves (glossopharyngeal and vagus nerves) and the sympathetic trunk have been suggested to be involved in the sensory innervation of the carotid artery and vagina [51,94,124]; Therefore, it may be prudent to administer a local anesthetic near the carotid artery during CEA. A recent single temporary CPB ultrasound [62,84,89,92,95] or indirect CPB ultrasound combined with infiltration of a local anesthetic USG in the perivascular region of the carotid artery [9,11,93,94] has become a new option to reduce the amount of intraoperative refilling of local anesthetic by the surgeon during CEA, while the use of deep CPB for CEA has decreased. However, direct infiltration of a local anesthetic into the perivascular area of the carotid artery may cause some side effects of cranial nerve palsy.9,11,93,94,127,128]
Safety considerations related to cervical plexus block
Paralysis of the phrenic nerve
The phrenic nerve emerges from the ventral crest from C3 to C5 and runs laterally medial to laterally down the surface of the anterior scalene beneath the prevertebral fascia. According to Castresana et al. , combined deep and superficial CPB causes acute diaphragmatic movement disorders in 61% of patients. Notably, conventional topical CPBs do not appear to affect the phrenic nerve , provided that the injection is made precisely in the subcutaneous tissue [77One of the reasons that not all patients receiving deep CPB develop diaphragmatic movement disorders may be due to anatomical differences, including dominance of the fifth cervical nerve and the presence or absence of an accessory phrenic nerve.129] In addition, the SCM muscle is an additional respiratory muscle, necessary for the weakening of the diaphragm [130–132] Deep CPB is known to be strongly associated with diaphragmatic paralysis , which in combination with relaxation of the SCM muscles may lead to a worse than previously assumed effect on airway function, especially in patients with clinically significant lung disease or suspected diaphragmatic movement disorders.133]
The prevertebral fascia (the deep layer of the deep cervical fascia) forms the tubular sheath of the spine and its associated muscles, such as the long and long cap muscles in front, the scalene muscles in the side, and the deep cervical muscles in the back.13,43] According to the literature, the prevertebral fascia appears to play a barrier role in the spread of local anesthetics.134] or even boils [26,135] create an airtight space , suggesting that the bulge in the prevertebral space does not extend sharply in any direction due to the compactness of this space  There is also evidence that local anesthesia can stretch the prevertebral fascia during stellate ganglion blocks  and that the local anesthetic is trapped in the PCS during the intervention of the CPB  More recently, using fresh cadavers, Seidel et al.  studied the propagation of an injectable dye solution injected into a PCS using an ultrasound technique. Therefore, the dye remained in the PCS, suggesting that the prevertebral fascia is impermeable, contrary to Pandit's hypothesis  Nevertheless, Seidel et al.  have suggested that a clinical trial is needed to see if phrenic nerve block can be prevented with intermittent CPB.
Unlike deep CPBs [42,64] og mesoscale brachial plexus block , which inevitably requires puncture of the prevertebral fascia and injection of a local anesthetic near the roots of the cervical spine, the likelihood of indirect CPB on ultrasound affecting the phrenic nerve may seem low, possibly due to the previously mentioned protective nature of the prevertebral fascia.26,134,135], which can also be seen in the examination of the corpses by Seidel et al.  and the location and course of the phrenic nerve  Martusevicius i in.  performed a regional anesthesia ultrasound technique similar to indirect CPB ultrasound in 60 patients, which did not cause arm weakness or respiratory distress, and in a study by Tran et al.97], despite local anesthetic deposition in the PCS between the SCM and the scalene muscle under ultrasound guidance, no cases of inadvertent brachial plexus block, Horner's syndrome, or dyspnea were observed. Consistent with these findings, two studies by Kim et al. [90,91] also showed no evidence of brachial plexus block, Horner's syndrome, or dyspnea after a single mid-CPB ultrasound examination in adult patients undergoing robotic thyroidectomy and in children and adolescents with rheumatic disease undergoing unipolar SCM muscle release with myectomy. In addition, Calderon et al.  reported that although diffusion of local anesthetic in PCS was observed during indirect CPB ultrasound, no diffusion of the anesthetic beyond the prevertebral fascia was detected, which may also be an important element supporting the thesis that the prevertebral fascia has protective properties. However, currently there is insufficient evidence to confirm the true nature of the prevertebral fascia, which needs to be explored in clinical trials.
Mechanical airway obstruction due to tissue edema or hematoma is a well-known surgical complication after various neck surgeries, including thyroidectomy.138] and CEA [139,140] Especially during CEA, surgical procedures involving dissection, traction, and retraction may cause damage to the facial nerve, the hypoglossal nerve, the vagus nerve and its branches (retrograde and superior laryngeal nerves), or the glossopharyngeal nerve in the operative field.141–144Among them, bilateral damage to the vagus nerve, recurrent laryngeal nerve, or hypoglossal nerve can lead to fatal upper airway obstruction .141,145Although data on cranial nerve blocks associated with isolated deep CPBs are sparse [59,61,127], it is likely that deep CPB may paralyze the glossopharyngeal, vagus, hypoglossal, and accessory nerves, especially when there is diffusion of anesthetic to the head, as there are extensive anastomoses between the inferior cranial and superior cervical nerves, although this is very likely a variable between individuals [51,53Therefore, it is important to remember that bilateral deep CPB can cause not only bilateral phrenic nerve paralysis, but also fatal airway obstruction by paralysis of the vagus or hypoglossal nerve. Most importantly, in patients with preexisting contralateral vagal (or recurrent laryngeal) or hypoglossal nerve injury, even unilateral deep CPB can result in complete airway obstruction. therefore, although pre-existing unilateral vocal cord paralysis is usually clinically asymptomatic [127,146], and unilateral hypoglossal nerve palsy causes minimal disability , routine preoperative history taking and physical examination of the tongue and vocal folds will be important in patients receiving deep CPB  as well as in patients undergoing CEA  regardless of the anesthetic technique.
As previously described, direct infiltration of a local anesthetic into the neck region during CEA by the surgeon or anesthesiologist can effectively block the pain associated with carotid sheath or arterial incision .124,148], but can also cause cranial nerve block side effects [9,11,93,94,127,128], in addition to decreased baroreceptor reflex [94Ultrasound techniques for infiltration of a local anesthetic in the neck region in conjunction with subcutaneous infiltration or indirect CPB have recently been introduced to reduce intraoperative supplementation of local anesthetic during CEA [9,11,93,94] According to Casutt et al. , ultrasound blockade of the cervical sheath by injecting a mixture of local anesthetic and contrast medium into the ventral side of the carotid artery causes extensive spread of the local anesthetic, which is confirmed by CT imaging after the blockade. Martusevicius et al. [9reported that transient hoarseness, facial paralysis, and dysphagia occurred in 72%, 13%, and 12% of patients, respectively, who received a combined indirect CPB infiltration and local anesthetic ultrasound. Therefore, bilateral infiltration of local anesthetic in the neck region can result in fatal airway obstruction.
Regarding indirect CPB, the spread pattern of the local anesthetic in PCS may be important. During a block at the interfascial level, many factors can affect the distribution of local anesthetic and the quality of the block, therefore precise needle placement and a deep understanding of fascial anatomy and tissue structure are required.149] Zhang i Li  argued that the PCS is actually an extension of the subcutaneous tissue and that the carotid sheath is connected to the subcutaneous adipose tissue without clearly delimiting the fascia. In the clinical setting, we have often observed that local anesthetic agents easily spread towards the carotid sheath, even when the tip of the injection needle is positioned between the scalene anterior or long head muscle and the scalene median during a posterior CPB indirect ultrasound approach (Grave. 4). Tran i ind.  compared ultrasound and CPB based on superficial landmarks in patients undergoing shoulder and clavicle surgery. However, the CPB ultrasound technique they used was actually an indirect CPB ultrasound method where 10 mL of anesthetic was injected into the PCS as described here, and not superficial CPB ultrasound, whereas landmark superficial CPB was essentially subcutaneous CPB. They reported no dyspnoea, desaturation, or brachial plexus block, but hoarseness or difficulty swallowing occurred in 10% of patients in the ultrasound group. Leblanc et al.  reported that dysphonia occurred in 12%, Horner's syndrome in 4%, and dysphagia in 2% of patients after a single interventional CPB ultrasound examination with 10 ml of local anesthetic for CEA, but intentionally inserting the needle tip near the carotid artery. Alilet et al.  failed to insert the needle tip near the cervical sheath during a single indirect CPB ultrasound with 10 ml local anesthetic for CEA and reported a very low incidence of hoarseness (2.4%) and hypoglossal palsy (2.4%). Therefore, it can be assumed that the occurrence of hoarseness and dysphagia after a single mid-CPB ultrasound examination may depend on blocking techniques as well as on the amount of local anesthetic injected. In contrast, when intermittent CPB was combined with cervical infiltration of local anesthetics, a significantly higher incidence of hoarseness and dysphagia was observed.9,93,94]
Hoarseness (dysphonia) possibly due to blockade of the vagus nerve or its branches (recurrent and superior laryngeal nerves), difficulty swallowing (dysphagia) possibly due to blockade of the vagus nerve and blockade of the facial nerve may be due to inward and upward spread of the local anesthetic during the ultrasound intervention in CPB. Transient dysphonia caused by ipsilateral vagus nerve, recurrent laryngeal block, or superior laryngeal nerve after indirect CPB on ultrasound is usually not clinically significant. However, bilateral blockade of the vagus, recurrent laryngeal or hypoglossal nerves can cause fatal airway obstruction. Therefore, bilateral intermittent CPB can be dangerous, and even unilateral CPB can lead to airway obstruction in patients with preexisting contralateral vagal or hypoglossal nerve damage, which may require routine preoperative testing. During ultrasound intervention in CPB, to avoid inadvertent cranial nerve blockade, it is recommended to place the needle tip of the PCS well beyond the carotid sheath, use a small amount of local anesthetic and inject the anesthetic slowly while observing local anesthetic spread, thus limiting medial spread of local anesthetic in the cervical sheath [90,91] unless cervical sheath lock is required.
Other negative effects
Horner's syndrome itself has no clinical consequences, but it is an unpleasant side effect, although it cannot be described as a complication.150The incidence of Horner's syndrome after intermittent CPB is debatable due to the position of the cervical sympathetic chains relative to the prevertebral fascia, the permeability of the prevertebral fascia, and the degree of local anesthetic spread from the PCS to the carotid sheath during the procedure. CPB's intervention may have some effect. Usui et al.  and Civelek in in.  described that the sympathetic chains in the neck lie directly under the prevertebral fascia covering the long muscles. on the contrary, in the 41st edition of Gray's Anatomy , it has been reported that the carotid sympathetic trunk lies in the prevertebral fascia posterior to the carotid artery. However, Horner's syndrome has been reported after superficial CPB , combined surface and deep CPB [59,63], indirect CPB ultrasound [92,98] and combined indirect CPB ultrasound and cervical infiltration of local anesthetic [9,11,94] But according to Lyons and Mills , out of 12 sections of the neck of the cadavers, in 2 cadavers the cervical sympathetic chain was found in the carotid artery. This anatomical variation may not only cause damage to the sympathetic chain during neck dissection or simple internal jugular vein catheterization , but it also affects the occurrence of Horner's syndrome during CPB with/without local anesthetic infiltration in the carotid artery.
The most common cause of accessory spinal nerve palsy is iatrogenic trauma during neck surgery, particularly operations located in the posterior cervical triangle.106,154] Anatomically, the accessory spinal nerve enters the posterior cervical triangle 2 cm above Erb's point, then runs diagonally along the posterior cervical triangle and terminates on the anterior surface of the upper trapezius muscle with many variations.155] In the posterior cervical triangle, the accessory nerve lies superficial to the prevertebral fascia ; Thus, the superficial CPB may be affected , but indirect CPB targeting the PCS below the SCM muscle is unlikely to affect the spinal accessory nerve 
Clarifying the classification of cervical plexus block
For a systematic naming of CPB techniques, we can propose three practical CPB classifications (Grave. 5), based on anatomical studies of the cervical fascia, nerve innervation and relevant clinical reports described in this review. The first technique is superficial CPB, which consists of a multi-directional or single subcutaneous injection in the area of the posterior lip of the SCM muscle, directed at the superficial branches of the cervical plexus, regardless of the use of the ultrasound technique. This superficial CPB can also be performed to selectively block one or more superficial branches of the cervical plexus using a landmark or ultrasound technique. Surface CPB is a very useful, safe and easy-to-learn tool that every regional anesthesiologist should know. The second technique is indirect CPB, which involves placing a needle in the PCS (between the SCM muscle and the prevertebral fascia) at the C4 level, targeting both the superficial branches of the cervical plexus and possibly the cervical sensory-motor branches of the uterus. plexus that supplies the SCM muscle. Intermediate CPB ultrasound is easy to learn and reproduce, but the possibility of side effects should not be overlooked. Finally, deep CPB involves placing a needle between the prevertebral fascia and the cervical nerve roots at the C2-C4 level while targeting both the superficial and deep branches of the cervical plexus. Despite some advantages, deep CPBs may require a risk-benefit analysis before implementation. To ensure safe and effective intermediate and deep CPB, the use of ultrasound technique is strongly recommended.
Three different target areas for cervical plexus block (CPB) in the cervical fascial spaces are illustrated schematically (Section C4). (A) The target area for superficial CPB is the subcutaneous tissue around the medial posterior margin of the sternocleidomastoid muscle (SCM). (B) The target area for indirect CPB is the space between the SCM muscle and the prevertebral fascia. (C) The target area for deep CPB is the space between the prevertebral fascia and the target transverse process.
CPB is performed in the neck area, which is very complex and requires many layers of fascia in a tight space. A new, more specific terminology for the cervical fascia has recently been proposed, but there is still disagreement about the exact identification and description of the cervical fascia, including the investing and prevertebral fascia and the carotid sheath. In addition, anatomical differences in the layers of the cervical fascia can significantly influence the results of any CPB method. Therefore, it is currently difficult to describe the actual results of each CPB approach, although most CPB methods are now performed accurately and safely under ultrasound guidance. In this review, we have covered in detail indirect CPB, which is a relatively new technique but has some controversial issues. Although the obstructive effects and potential adverse effects of indirect CPB require further investigation, we simply classified CPB into three general approaches, superficial, intermediate, and deep, based on the target area of each approach, which is easily identified by ultrasound.
1.Kesisoglou I, Papavramidis T, Michalopoulos N, Ioannidis K, Trikoupi A, Sapalidis K et al. Superficial selective cervical plexus block after total thyroidectomy: a randomized trial.Neck head.2010;32: 984-8.[PubMed][Google Scholar]
3.Perisanidis G, Saradeas T, Kostopanagiotou G. Combined ultrasound-guided median nerve block and deep cervical plexus block for regional anesthesia in oral and maxillofacial surgery.Dentomaxillofac Radiol.2013;42:29945724. [Free PMC article][PubMed][Google Scholar]
4.Suresh S, Barcelona SL, Young NM, Seligman I, Heffner CL, Coté CJ. Postoperative pain relief in children undergoing tympanomastoid surgery: is regional blockade better than opioids?Anesth Analg.2002;94: 859-62.[PubMed][Google Scholar]
5.Mariappan R, Mehta J, Massicotte E, Nagappa M, Manninen P, Venkatraghavan L. Effect of superficial cervical block on postoperative quality of recovery after anterior discectomy and cervical anastomosis: a randomized controlled trial.Kan J. Anaesth.2015;62: 883-90.[PubMed][Google Scholar]
7.Shin HY, Kim DS, Kim SS. Superficial cervical plexus block in the treatment of herpes zoster neuralgia in a C3 dermatome: a case report.J With a case manager2014;8:59. [Free PMC article][PubMed][Google Scholar]
8.Ramachandran SK, Picton P, Shanks A, Dorje P, Pandit JJ. Comparison of intervention and subcutaneous carotid plexus block for carotid endarterectomy.br. J. Anaesth.2011;107: 157-63.[PubMed][Google Scholar]
9.Martusevicius R, Świątek F, Jørgensen LG, Nielsen HB. Ultrasound-guided local anesthesia for carotid endarterectomy: a prospective observational study.Eur J Vasc Endovasc Surg.2012;44: 27-30.[PubMed][Google Scholar]
10.Stoneham MD, Doyle AR, Knighton JD, Dorje P, Stanley JC. Prospective randomized comparison of deep versus superficial carotid plexus block during carotid endarterectomy surgery.Anesthesiology.1998;89: 907-12.[PubMed][Google Scholar]
11.Rössel T, Kersting S, Heller AR, Koch T. Combination of high-resolution ultrasound-guided perivascular anesthesia of the internal carotid artery and the intermediate carotid plexus for carotid surgery.USG with Biol.2013;39: 981-6.[PubMed][Google Scholar]
12.Pandit JJ, Satya-Krishna R, Gration P. Superficial or deep carotid plexus block in carotid endarterectomy: a systematic review of complications.br. J. Anaesth.2007;99: 159-69.[PubMed][Google Scholar]
17.Saranteas T, Paraskeuopoulos T, Anagnostopoulou S, Kanellopoulos I, Mastoris M, Kostopanagiotou G. Ultrasound anatomy of the cervical paravertebral space: a preliminary study.Surg Radiol Res.2010;32: 617-22.[PubMed][Google Scholar]
18.Guay J, Grabs D. A cadaver study to determine the minimum volume of methylene blue or naphthol black required for complete staining of nerves associated with anesthesia during breast surgery.Clin Anat.2011;24: 202-8.[PubMed][Google Scholar]
20.Shakespeare TJ, Tsui BC. Intermittent hoarseness during continuous brachial plexus catheter infusion due to incomplete cervical sheath.Acta Anaesthesiol Scand.2013;57: 1085-6.[PubMed][Google Scholar]
21.Zhang M, Lee AS. Between the sternocleidomastoid and trapezius muscles there is no ependymal layer of deep cervical fascia.Otolaryngological head and neck surgeon.2002;127: 452-4.[PubMed][Google Scholar]
29.Moncada R, Warpeha R, Pickleman J, Spak M, Cardoso M, Berkow A et al. Mediastinitis caused by odontogenic and deep cervical infection. Anatomical routes of spread.Envelopes.1978;73: 497-500.[PubMed][Google Scholar]
30.Stecco A, Meneghini A, Stern R, Stecco C, Imamura M. Ultrasound in myofascial neck pain: a randomized clinical trial for diagnosis and follow-up.Surg Radiol Res.2014;36: 243-53.[PubMed][Google Scholar]
32.Standing SAnatomia Greya.41st edition London: Churchill Livingstone Elsevier; 2016. p. 41.[Google Scholar]
34.Grodinsky M, Holyoke EA. Fascia and fascial spaces in the head, neck and adjacent areas.I am J Anat.1938;63: 367-408. [Google Scholar]
39.Palliyalil M, Anehosur V, Joshi A, Acharya S. Histological evaluation of carotid sheath in patients with oral squamous cell carcinoma.J Oral and Maxillofacial Surg.2017;75: 2465-76.[PubMed][Google Scholar]
42.Usui Y, Kobayashi T, Kakinuma H, Watanabe K, Kitajima T, Matsuno K. Anatomical basis of deep cervical plexus and cervical sympathetic blockade using ultrasound-guided technique.Anesth Analg.2010;110: 964-8.[PubMed][Google Scholar]
43.Moore K., Dalley AF, Agur AM.Clinically oriented anatomy.7. udgave, Balimore: Lippincott Williams & Wilkins; 2014. s. 988.[Google Scholar]
44.Havet E, Duparc F, Tobenas-Dujardin AC, Muller JM, Fréger P. Morphometric study of the innervation of the shoulder and subclavian from the branches of the intermediate and lateral supraclavicular nerves.Surg Radiol Res.2007;29: 605-10.[PubMed][Google Scholar]
45.de Arruda JV, Sartini Filho R, Neder AC, Ranali J. Intraoral anesthesia of the cervical plexus responsible for the sensory innervation of the platypus muscle or skin of the neck.Rev Bras Odontol.1974;31: 229-31.[PubMed][Google Scholar]
46.Standing SAnatomia Greya.41st edition London: Churchill Livingstone Elsevier; 2016. pp. 463–4.[Google Scholar]
47.Paraskevas GK, Natsis K, Nitsa Z, Mavrodis A, Kitsoulis P. Unusual morphological pattern and distribution of the anterior cervix: a case report.Rom J Morphol Embryol.2014;55: 993-6.[PubMed][Google Scholar]
48.Brennan PA, Alam P, Ammar M, Tsiroyannis C, Zagkou E, Standring S. Sternocleidomastoid innervation from an anomalous nerve arising from the hypoglossal nerve: a prospective study of 160 neck sections.Surg Radiol Res.2017;39:205-9.[PubMed][Google Scholar]
50.Khaki AA, Shokouhi G, Shoja MM, Farahani RM, Zarintan S, Khaki A et al. Ansa cervicalis as a variant of the accessory spinal nerve plexus: a case report.Clin Anat.2006;19:540–3.[PubMed][Google Scholar]
51.Shoja MM, Oyesiku NM, Shokouhi G, Griessenauer CJ, Chern JJ, Rizk EB et al. A comprehensive review of potential importance during skull base and neck surgery, part II: Glossopharyngeal, Vagus, Accessory and Subglossal Nerves, and Cervical Spinal Nerves 1-4.Clin Anat.2014;27: 131-44.[PubMed][Google Scholar]
54.Merle JC, Mazoit JX, Desgranges P, Abhay K, Rezaiguia S, Dhonneur G et al. Comparison of two techniques for cervical plexus block: evaluation of efficacy and systemic toxicity.Anesth Analg.1999;89: 1366-70.[PubMed][Google Scholar]
56.Wan Q, Yang H, Li X, Lin C, Ke S, Wu S et al. Ultrasound-guided deep cervical plexus block and fluoroscopy for the treatment of cervical headache.Biomed Res Int.2017;2017:4654803. [Free PMC article][PubMed][Google Scholar]
58.Aunac S, Carlier M, Singelyn F, De Kock M. Analgesic effect of bilateral combined superficial and deep cervical plexus block administered before thyroid surgery under general anesthesia.Anesth Analg.2002;95: 746-50.[PubMed][Google Scholar]
59.Pintaric TS, Hocevar M, Jereb S, Casati A, Novak Jankovic V. A prospective randomized comparison between combined (deep and superficial) and superficial cervical plexus block with levobupivacaine for minimally invasive parathyroidectomy.Anesth Analg.2007;105: 1160–3.[PubMed][Google Scholar]
60.Davies MJ, Silbert BS, Scott DA, Cook RJ, Mooney PH, Blyth C. Superficial and deep carotid block in carotid artery surgery: a prospective study of 1000 blocks.Reg Anest.1997;22: 442-6.[PubMed][Google Scholar]
61.Ivanec Z, Mazul-Sunkol B, Lovricević I, Sonicki Z, Gvozdenovic A, Klican K et al. Superficial and combined (deep and superficial) carotid plexus block in carotid endarterectomy.Acta Clin Croatia.2008;47: 81-6.[PubMed][Google Scholar]
62.Pandit JJ, Bree S, Dillon P, Elcock D, McLaren ID, Crider B. Comparison of superficial and combined (superficial and deep) carotid plexus block in carotid endarterectomy: a prospective randomized trial.Anesth Analg.2000;91: 781-6.[PubMed][Google Scholar]
63.Sait Kavaklı A, Kavrut Öztürk N, Umut Ayoğlu R, Sağdıç K, Çakmak G, İnanoğlu K et al. Comparison of complex (deep and superficial) and indirect US-guided carotid plexus block during carotid endarterectomy.J Cardiothoracic Anesthesia.2016;30: 317-22.[PubMed][Google Scholar]
64.Dhonneur G, Saidi NE, Merle JC, Asfazadourian H, Ndoko SK, Bloc S. Demonstration of injection spread with deep cervical plexus block: a case series.Reg Anesth Ból Med.2007;32: 116-9.[PubMed][Google Scholar]
67.Saradeas T, Kostopanagiotou GG, Anagnostopoulou S, Mourouzis K, Sidiropoulou T. En simpel metode til dyb ultrasoundsstyret cervical nerve occlusion.Intensive anesthesia treatment.2011;39: 971-2.[PubMed][Google Scholar]
68.Shin HJ, Yu HN, Yoon SZ. Ultrasound-guided subcutaneous carotid plexus block for carotid endarterectomy in a patient with chronic obstructive pulmonary disease.J. Anest.2014;28: 304-5.[PubMed][Google Scholar]
69.Herbland A, Cantini O, Reynier P, Valat P, Jougon J, Arimone Y et al. Bilateral superficial cervical plexus block with 0.75% ropivacaine given before or after surgery does not prevent postoperative pain after total thyroidectomy.Reg Anesth Ból Med.2006;31: 34–9.[PubMed][Google Scholar]
72.Maybin J, Townsley P, Bedforth N, Allan A. Ultrasound-guided supraclavicular nerve block: first technical description and relevance to shoulder surgery under regional anaesthesia.Anesthesia.2011;66: 1053-5.[PubMed][Google Scholar]
74.Ritchie MK, Wilson CA, Grose BW, Ranganathan P, Howell SM, Ellison MB. Ultrasound-guided greater auricular nerve block as the sole anesthetic during ear surgery.Clinical practice.2016;6:856. [Free PMC article][PubMed][Google Scholar]
78.Mayhew D, Sahgal N, Khirwadkar R, Hunter JM, Banerjee A. Analgesic efficacy of bilateral superficial carotid plexus block in thyroid surgery: a meta-analysis and systematic review.br. J. Anaesth.2018;120: 241-51.[PubMed][Google Scholar]
79.Kannan S, Surhonne NS, R CK, B K, D DR, RS RR. Effect of bilateral superficial carotid plexus block on sevoflurane consumption during thyroid surgery under general anesthesia under entropy control: a prospective randomized trial.Korean Anesthesia J.2018;71: 141-8. [Free PMC article][PubMed][Google Scholar]
80.Girard F, Quentin C, Charbonneau S, Ayoub C, Boudreault D, Chouinard P et al. Superficial cervical plexus block for transient analgesia in subintestinal and occipital craniotomy: a randomized trial.Kan J. Anaesth.2010;57: 1065-70.[PubMed][Google Scholar]
81.Tubbs RS, Loukas M, Shoja MM, Salter EG, Oakes WJ, Blount JP. Cervical vagal access via the posterior cervical triangle: cadaver feasibility study with potential use in vagal nerve stimulation procedures.J Spine Neurosurgeon.2006;5: 540-2.[PubMed][Google Scholar]
82.Standing SAnatomia Greya.41st edition London: Churchill Livingstone Elsevier; 2016. p. 445.[Google Scholar]
83.Merdad M, Crawford M, Gordon K, Papsin B. Unexplained fever after bilateral superficial cervical block in children undergoing cochlear implantation: an observational study.Kan J. Anaesth.2012;59: 28-33.[PubMed][Google Scholar]
84.Koköfer A, Nawratil J, Felder TK, Stundner O, Mader N, Gerner P. Ropivacaine 0.375% versus 0.75% with prilocaine for indirect carotid plexus block in carotid endarterectomy: a randomized trial.Eur J Anesthesiology.2015;32: 781-9.[PubMed][Google Scholar]
85.Barone M, Diemunsch P, Baldassarre E, Oben WE, Ciarlo M, Wolter J et al. Carotic endarterectomy with intermediate carotid plexus block.Tex Heart Inst J.2010;37: 297-300. [Free PMC article][PubMed][Google Scholar]
86.Kefalianakis F, Koeppel T, Geldner G, Gahlen J. Ultrasound-guided carotid artery surgery in lateral colic anesthesia.Anasthesiol Intensive pain treatment in acute cases2005;40: 576-81.[PubMed][Google Scholar]
87.Ciccozzi A, Angeletti C, Guetti C, Pergolizzi J, Angeletti PM, Mariani R et al. Regional anesthetic techniques in carotid surgery: current knowledge.J Sonography.2014;17: 175-83. [Free PMC article][PubMed][Google Scholar]
89.Calderon AL, Zetlaoui P, Benatir F, Davidson J, Desebbe O, Rahali N et al. Ultrasound-guided intermediate carotid plexus block for carotid endarterectomy using a novel anterior approach: a two-center prospective observational study.Anesthesia.2015;70: 445-51.[PubMed][Google Scholar]
90.Kim JS, Lee J, Soh EY, Ahn H, Oh SE, Lee JD et al. Analgesic effects of ultrasound-guided intercostal plane block and ultrasound-guided intercostal plexus block after single-incision robotic biaxial thyroidectomy: a prospective randomized controlled trial.Reg Anesth Ból Med.2016;41: 584-8.[PubMed][Google Scholar]
91.Kim JS, Joe HB, Park MC, Ahn H, Lee SY, Chae YJ. Postoperative ultrasound-guided analgesic effect of the intermediate cervical plexus block in unipolar sternocleidomastoid release with myectomy in children and adolescents with congenital torticollis: a prospective randomized controlled trial.Reg Anesth Ból Med.2018;43: 634-40.[PubMed][Google Scholar]
92.Leblanc I, Chterev V, Rekik M, Boura B, Costanzo A, Bourel P et al. Safety and efficacy of the US-guided indirect plexus block in carotid artery surgery.Anaesth Crit Care Ból Med.2016;35: 109-14.[PubMed][Google Scholar]
93.Mądro P, Dąbrowska A, Jarecki J, Garba P. Anesthesia for carotid endarterectomy. Ultrasound-guided superficial/interstitial cervical plexus block combined with carotid sheath infiltration.Intensive anesthesia Ther.2016;48:234-8.[PubMed][Google Scholar]
94.Seidel R, Zukowski K, Wree A, Schulze M. Ultrasound-guided indirect cervical block and perivascular local anesthetic infiltration for carotid endarterectomy: a randomized controlled trial.Stunned.2016;65: 917-24.[PubMed][Google Scholar]
95.Alilet A, Petit P, Devaux B, Joly C, Samain E, Pili-Floury S et al. Ultrasound-guided indirect carotid block versus superficial carotid block in carotid endarterectomy: the CERVECHO randomized controlled trial.Anaesth Crit Care Ból Med.2017;36: 91-5.[PubMed][Google Scholar]
96.Herring AA, Stone MB, Frenkel O, Chipman A, Nagdev AD. Ultrasound-guided superficial cervical plexus block for anesthesia and analgesia in acute care settings.Am J Emerg Med.2012;30: 1263-7.[PubMed][Google Scholar]
99.Senapathi TGA, Widnyana IMG, Aribawa IGNM, Wiryana M, Sinardja IK, Nada IKW et al. Ultrasound-guided bilateral superficial carotid plexus block is more effective than the pioneering technique in reducing pain after thyroidectomy.J Pain Res.2017;10: 1619–22. [Free PMC article][PubMed][Google Scholar]
101.Koizumi M, Horiguchi M, Sekiya S, Isogai S, Nakano M. A case of the human sternocleidomastoid muscle further innervated by the hypoglossal nerve.Okajimas Folia Anat Jpn.1993;69: 361-7.[PubMed][Google Scholar]
103.Paraskevas G, Lazaridis N, Spyridakis I, Koutsouflianiotis K, Kitsoulis P. Abnormal innervation af sternocleidomastoidmusklen af den traegände cervicale nerve: en case-rapport.J Clin Diagn Res.2015;9: AD01–2. [Free PMC article][PubMed][Google Scholar]
106.Tubbs RS, Sorenson EP, Watanabe K, Loukas M, Hattab E, Cohen-Gadol AA. Histological confirmation of nerve cell bodies along the spinal accessory nerve.Br J. Neurosurgeon.2014;28: 746-9.[PubMed][Google Scholar]
108.Pu YM, Tang EY, Yang XD. Innervation of the trapezius muscle by the accessory spinal nerve and branches of the cervical plexus.Int J Oral Maxillofacial Surgery.2008;37: 567-72.[PubMed][Google Scholar]
109.Fitzgerald MJ, Comerford PT, Tuffery AR. Sources of innervation of the neuromuscular spindles in the sterno-mastoid and trapezius muscles.J Anat.1982;134: 471-90. [Free PMC article][PubMed][Google Scholar]
110.Yoshizaki F. Innervation of the sternocleidomastoid muscle in man and rabbit.Dobraama Igakkai Zasshi.1961;73: 159-71. [Google Scholar]
113.Min SH, Chang SH, Jeon SK, Yoon SZ, Park JY, Shin HW. Posterior ear pain caused by sternocleidomastoid trigger points, aggravated by psychological factors - Case report -Korean Anesthesia J.2010;59 Appendix: S229–32. [Free PMC article][PubMed][Google Scholar]
114.Bodes-Pardo G, Pecos-Martin D, Gallego-Izquierdo T, Salom-Moreno J, Fernandez-de-Las-Peñas C, Ortega-Santiago R. Manual therapy for cervical headache and active sternocleidomastoid trigger point: pilot randomized clinical trial.J. Manipulacyjny Physiol Ther.2013;36: 403-11.[PubMed][Google Scholar]
115.Shinozaki T, Sakamoto E, Shiiba S, Ichikawa F, Arakawa Y, Makihara Y et al. Cervical plexus block helps diagnose orofacial pain originating from the cervical structures.Tohoku J Exp Med.2006;210: 41-7.[PubMed][Google Scholar]
116.North American collaborators on a study of symptomatic carotid endarterectomy. Barnett HJM, Taylor DW, Haynes RB, Sackett DL, Peerless SJ et al. Beneficial effect of carotid endarterectomy in symptomatic patients with high degree of carotid stenosis.N Engl J Med.1991;325: 445-53.[PubMed][Google Scholar]
117.Bonati LH, Dobson J, Featherstone RL, Ederle J, van der Worp HB, de Borst GJ et al. Long-term outcomes after stenting versus endarterectomy in the treatment of symptomatic carotid artery stenosis: a randomized international carotid stenting trial (ICSS).Lancet.2015;385: 529-38. [Free PMC article][PubMed][Google Scholar]
119.Schechter MA, Shortell CK, Scarborough JE. Regional versus general anesthesia for carotid endarterectomy: perspective of the American College of Surgeons National Quality Improvement Program.Surgery.2012;152: 309-14.[PubMed][Google Scholar]
121.Kfoury E, Dort J, Trickey A, Crosby M, Donovan J, Hashemi H et al. Carotid endarterectomy under local and/or regional anesthesia is associated with a lower risk of myocardial infarction compared with general anesthesia: an analysis of the National Surgical Quality Improvement Program database.Vascular.2015;23: 113-9.[PubMed][Google Scholar]
122.de Sousa AA, Filho MA, Faglione W, Jr, Carvalho GT. Superficial and combined carotid plexus block in carotid endarterectomy: a prospective randomized trial.Surg Neurol.2005;63 Appendix 1:S22–5.[PubMed][Google Scholar]
123.Umbrain VJ, van Gorp VL, Schmedding E, Debing EE, von Kemp K, van den Brande PM et al. Ropivacaine 3.75 mg/ml, 5 mg/ml or 7.5 mg/ml for the treatment of carotid plexus block during carotid endarterectomy.Reg Anesth Ból Med.2004;29: 312-6.[PubMed][Google Scholar]
125.Kavrut Ozturk N, Kavakli AS, Sagdic K, Inanoglu K, Umot Ayoglu R. A randomized controlled trial investigating the effect of adding a mandibular block to a carotid plexus block for carotid endarterectomy.J Cardiothoracic Anesthesia.2018;32: 877-82.[PubMed][Google Scholar]
127.Harris RJ, Benveniste G. Recurrent laryngeal nerve block in patients undergoing carotid endarterectomy during carotid plexus block.Intensive anesthesia treatment.2000;28: 431-3.[PubMed][Google Scholar]
129.Castresana MR, Masters RD, Castresana EJ, Stefansson S, Shaker IJ, Newman WH. Prevalence and clinical significance of hemidiaphragmatic palsy in patients undergoing carotid endarterectomy under carotid plexus block anesthesia.J Neurosurgical Anesthesia.1994;6:21–3.[PubMed][Google Scholar]
130.Campbell E.J. The role of the scales and sterno-mastoid muscles in respiration in healthy subjects. electromyographic examination.J Anat.1955;89: 378-86. [Free PMC article][PubMed][Google Scholar]
131.Lisboa C, Pare PD, Pertuze J, Contreras G, Moreno R, Guillemi S et al. Inspiratory muscle function in unilateral paralysis of the diaphragm.I am Rev Respira Dis.1986;134: 488-92.[PubMed][Google Scholar]
132.Bonnevie T, Gravier FE, Ducrocq A, Debeaumont D, Viacroze C, Cuvelier A et al. Exercise control in patients with diaphragmatic palsy.Respir Physiol Neurobiol.2018;248:31–5.[PubMed][Google Scholar]
137.Urmey WF, Talts KH, Sharrock NE. Percent incidence of hemidiaphragmatic palsy associated with diascal anesthesia of the brachial plexus diagnosed by ultrasound.Anesth Analg.1991;72: 498-503.[PubMed][Google Scholar]
138.Suzuki S, Yasunaga H, Matsui H, Fushimi K, Saito Y, Yamasoba T. Factors associated with neck hematoma after thyroidectomy: a retrospective analysis using a Japanese hospital patient database.Medicine (Baltimore)2016;95:e2812. [Free PMC article][PubMed][Google Scholar]
141.Reifenberger G, Prior R, Deckert M, Wechsler W. Epidermal growth factor receptor expression and growth fraction in human tumors of the nervous system.Virchows Arch A Pathol Anat Histopatol.1989;414: 147-55.[PubMed][Google Scholar]
142.Fokkema M, de Borst GJ, Nolan BW, Indes J, Buck DB, Lo RC et al. Clinical significance of cranial nerve injury after carotid endarterectomy.Eur J Vasc Endovasc Surg.2014;47: 2-7. [Free PMC article][PubMed][Google Scholar]
143.Hye RJ, Mackey A, Hill MD, Voeks JH, Cohen DJ, Wang K et al. Incidence, outcomes, and impact on quality of life of cranial nerve injury in a study of carotid revascularization versus stenting.J. Vasc Surg.2015;61: 1208-14. [Free PMC article][PubMed][Google Scholar]
144.Hertzer NR, Feldman BJ, Beven EG, Tucker HM. A prospective study of the incidence of cranial nerve injuries during carotid endarterectomy.Surg Gynecol Obstet.1980;151: 781-4.[PubMed][Google Scholar]
146.Weiss A, Isselhorst C, Gahlen J, Freudenberg S, Roth H, Hammerschmitt N et al. Acute respiratory failure after deep cervical plexus block for carotid endarterectomy due to bilateral recurrent laryngeal nerve palsy.Acta Anaesthesiol Scand.2005;49: 715-9.[PubMed][Google Scholar]
148.Casutt M, Breitenmoser I, Werner L, Seelos R, Konrad C. Ultralydsstyret carotisokklusion for carotis endarterectomy: case series of graft spread.Heart Pulmonary vessels.2015;7: 168-76. [Free PMC article][PubMed][Google Scholar]
151.Civelek E, Karasu A, Cansever T, Hepgul K, Kiris T, Sabanci A et al. Surgical anatomy of the cervical sympathetic trunk during anterolateral approach to the cervical spine.Eur Spine J.2008;17: 991-5. [Free PMC article][PubMed][Google Scholar]
152.Standing SAnatomia Greya.41st edition London: Churchill Livingstone Elsevier; 2017. P. 468.[Google Scholar]
156.Tubbs RS, Salter EG, Wellons JC, 3rd, Blount JP, Oakes WJ. Superficial landmarks of the accessory spinal nerve in the posterior cervical triangle.J Spine Neurosurgeon.2005;3: 375-8.[PubMed][Google Scholar]
157.Townsley P, Ravenscroft A, Bedforth N. Ultrasound-guided spinal accessory nerve block for the diagnosis and treatment of trapezius myofascial pain.Anesthesia.2011;66: 386-9.[PubMed][Google Scholar]
Articles fromKorean Journal of Anesthesiologygiven here courtesyThe Korean Society of Anesthesiologists