The blocks of the face remained the poor relations of the peripheral locoregional anaesthesia. Except some pilot centers, the disaffection of these blocks is due to a group of factors: knowledge necessary of the complexes anatomy of facial innervation, the technicality of realisation, the frequency of bilateral blocks, the fear of incidents on a very vascularised zone like the face. However with the evolution these last years of the locoregional anaesthesia, the creation of practice formative centers, these blocks start to diffuse itself. The contribution of new molecules of anaesthetic less toxic buildings, the neurostimulation which found its place, even on the level of the face, made grow the benefice risks ratio. The rise of the ambulatory practices, to which the blocks of face are adapted perfectly, gave an impulse to these practices, in spite of very interesting at fragile or old patients and in urgency. Finally a good collaboration with the surgical operator will allow a better precision in the indication of these blocks thus reducing the risks of incidents. |
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performing |
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Great auricular nerve block The great auricular nerve is a terminal branch of the superficial
cervical plexus; it moves towards the ear lobe according to an axis
passing by the posterior edge of SCM (Erb point) and mastoid. |
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For the puncture the patient must be positioned with the head turned towards the side opposed to the block [18]. The first reference mark is the mastoid (to mark it with the pen); the second reference mark, the lateral edge of SCM on the cricoid level. The block will be done on the line joining together these 2 points. The puncture point is done to 10 mm of the point of SCM; the needle passes in infradermic and moves towards the mastoid, the injection is done throughout way. |
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The injection is very slow with 7 ml of anaesthetic solution, while advancing towards the mastoid. After the shrinking of the needle a discrete massage supports the diffusion of the product. The territory supplies by the great auricular nerve is external ear, in its inferior and posterior zone (half inferior external ear), as well as a small cutaneous territory of the angle of the mandible. |
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This block is very easy, simple and with many success. The indications are in surgery: all acts on the external ear, repairing surgery with local scrap. In emergency: wounds of the external ear. No incident is noted, except, if the puncture is too deep, a diffusion on the facial nerve is possible, with a transitory paresis. |
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| Lesser occipital nerve block The lesser
occipital nerve is a terminal branch of the superficial cervical plexus
on the C2 level; it leaves behind SCM and moves towards postero-superior
zone of the ear lobe. |
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A "trick" can facilitate the block: the needle will be slightly curved and will be able in a way, to inject the anaesthetic solution behind the ear lobe, parallel to this one. |
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The injection will be particularly slow here, to make it less sensitive. One needs 4 ml of anaesthetic solution. After the shrinking of the needle a discrete massage supports the diffusion of the product.
The territory supplies by the lesser occipital nerve is, ear lobe in postero-superior zone ("9 hours to 12 hours") where the nerve branches supply the sensitivity of the lobe [27]. The lesser occipital block is very easy, simple with big efficacy. The indications of this block is in surgery all acts on the ear lobe. In emergency: wounds of the scalp in occipital zone. Only disadvantage with this block, the injection, which is sensitive; the slowness of the injection will decrease the pain. |
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Indications With surgery type Tegumental surgery The explosion of the indications of the surgery of facial surface made strongly develop the requests for facial blocks. Practically all the teguments are accessible to these techniques. The carcinologic surgery of face (basocellular tumour and spinocellular tumour) with or without local scrap of rebuilding is integrated perfectly in this diagram [7, 18, 19], the more so as it is often practised at subjects at the risks (old patient, or at the patient risk) and more and more, into ambulatory surgery. Plastic surgery and cosmetic like face lipostructure, localised repair of scars, face lifting and especially, upper and lower blepharoplasty, surgery of the lips, the chin, and the "separated" ears. In emergency the wounds of the face also profit from these techniques [7]: indeed the interest of small volume of local anaesthetic, not deforming the banks of the wound, will facilitate repair [7]. The anaesthesia for the scalp is included in the same category that it is in emergency, or to ensure a good postoperative analgesia in neurosurgery. Thus the face and the upper eyelids will be accessible with supraorbital block and supratrochlear block; the cheek and the lips with an infraorbital block or maxillary block; for the nose one will need bilateral infraorbital and nasal blocks; finally for the chin and the inferior lips a mental block is enough. However for broad acts covering several territories it is to better extend nervous blocking; thus for a lipostructure of the face interesting the maxillary territory and the mandibular territory in their totality. It is advised to make maxillary and mandibular blocks at their origin, if one chooses a regional anaesthesia. Maxillofacial surgery In this indication the alone regional anaesthesia is exceptionally used [7]. Nevertheless simple gestures as the mandibular osteotomy can be carried out under blocks [21]. Generally these techniques accompany a traditional general anaesthesia to carry out an operational analgesia and especially great quality postoperative analgesia. Practically all the facial bone surgery can be performed with complementary block of the trigeminal branches; it is then preferable to perform these blocks at a waked up patient, especially if one chooses a neurostimulation. Nasal surgery The rhinoplasty, associating blocks of face and general anaesthesia optimizes comfort, and the hemodynamics effects and gets a great quality postoperative analgesia. With the operational circumstances and patient It is an indication of choice at the subjects at the risks:
Interesting indication also in emergency, at the patient not with jeun, with an often surface surgery. Within the framework of ambulatory surgery the these blocks have a dominating place, allowing, acts in full safety with a remarkable residual analgesia facilitating the return with the social life in the day surgery. Contraindications The general counter-indications are those of any regional anaesthesia,
in particular [27]: The counter-indications due to the patient are especially:
The reserves due to the operator must be taken into account. The variable level of difficulty of these blocks is solved only by one anatomical knowledge and a hands-on training preliminary [7, 27]. A few blocks are of easy and durable acquisition: supraorbital, infraorbital, mental, nasal, ear block, very safe from serious complications. On the other hand the blocks carried out in the "plexus" beginning, like the maxillary nerve and the mandibular nerve, are more delicate, with a rate of less raised success, even for accustomed, and with risks of complications raised in the literature. Only the neurostimulation although not evaluated, seems in this case to facilitate the access to these blocks. Blocks for analgesia Postoperative analgesia The tegumental surgery can be controlled in postoperative analgesia plan by prolonged facial blocks. A local anaesthetic of long duration, with an additive drug, allows a very good quality of postoperative analgesia (EVA < III), during at least ten hours. In certain cases, a postoperative analgesic block could be performed after the end of surgery. Catheters Some rare indications of prolonged analgesia by perineural catheter are described [28, 29, 30]; primarily within the framework of a major carcinologic surgery (postoperative analgesia) or of a complementary treatment to an algic pathology rebel with the traditional treatments, like an in eradicable orofacial cancer [28]. They will get a good quality and stable analgesia. The sites of realisation are the nerves located in a fossa: maxillary nerve in rotundum foramen (suprazygomatic way) or by infrazygomatic way [30]; mandibular nerve near the oval foramen. The technique of realisation of these catheters is same with that of the simple block except that the perform is optimized by the use of motor stimulation for the mandibular nerve. The catheters will be introduced only one centimetre beyond the nozzle and will be fixed with a wire (the head being very mobile). Currently the choice rather goes worms of the discontinuous injections with a local anaesthetic to low concentration (ropivacaine 0,2%). On a short series as a double blind study (8 patients) a team showed that the postoperative analgesics consumption over 4 postoperative days was very low in the catheter group, and very significant compared to the group without regional anaesthesia [30]. Medical indication For a long time the nerves of the face and especially the trigeminal nerve, were targeted for the treatment of the pains on the level of the face [1, 31]. Some indications with diagnostic and therapeutic aiming exist on the level of the face. All the neuralgias of the maxillary nerve (superior alveolar nerve), and the mandibular nerve (inferior alveolar nerve), can be relieved by blocks. Nervous alcoholisations can use the same procedures as those, which are employed for the anaesthetic blocks. Rare but effective indications exist like the treatment with mandibular block, of a trismus associated a hypoxic encephalopathy [32]. COMPLICATIONS Vascular complication The facial vascular richness is the essential cause of the major risk, which is the vascular breach [7, 18, 21] with on the pharmacological plan an intense and fast resorption of the anaesthetic solution and the possibility of an intravascular injection. All the nerves are accompanied by an artery (supra and infraorbital) or close to a significant arterial axis (mandibular nerve and maxillary artery); only the maxillary nerve with the foramen rotundum is above the vessels. In order to have a time of rise of the plasmatic concentrations in the local anaesthetic, longest possible it is necessary: to inject most slowly possible, to use small volumes and to associate an additive drug, standard clonidine. Neurological complication The only notorious accidents are the extension of the anaesthesia to the motor nerves: facial paralysis, ptose of superior eyelid; all these incidents are regressive spontaneously. The specific accident is the risk of paraesthesias due to the wound of one nerve at the exit of its foramen with oedema and suffering: the injection in the foramen is to be rejected formally. Articular complication A characteristic: the intramuscular injection in the pterygoid muscles can involve a blocking of the temporomandibular articulation with limited oral opening and trismus [33]. Toxic complication They are due either to the vascular passage, or with a fast resorption of the anaesthetic solution. They do not present characteristics and are superposable with those of the other peripheral blocks (arm or leg). CONCLUSION The regional anaesthesia of the face is accessible by two types of blocks; deep blocks supplies a large territory, specialised perform and not easy realisation; and the superficial blocks of very easy access and simple to realise, but with more reduced territories where they could be associated. |
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Movie of great auricular nerve block 
