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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| Maxillary nerve block | ||
The maxillary nerve is accessible to the level from the foramen rotundum. This level the blocking of the terminal maxillary branches gives total maxillary block. The material for performing this block is standard neurostimulation needle, with court bevel of 50 mm (24G) connected to a syringe luer lock; a nervestimulator allowing to lengthen the time of the duration of stimulation starting from 0,3 milliseconds (ms). |
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A cutaneous pen marker.For this approach, the patient will have the turn ed head on the side opposed to the puncture; the operator will be side of the puncture. Two techniques are possible. |
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| Traditional procedure The point of puncture is done with the junction of two lines: a vertical line, the lateral bone orbital wall and a horizontal line, the zygomatic arch [6]. It is in this bone angle that the needle [7] will be introduced. The first direction is perpendicularly at the skin until the bone contact (approximately 10 to 15 mm), on this level, one finds the temporal muscle; the second direction move the needle, according to a caudal and medial axis by aiming at labial commeasure on the same side. In this space, the penetration is very easy, it is necessary to advance of 20 mm to obtain a total penetration of the needle from approximately 30 to 35 mm in total; one injects on this level. |
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| Procedure with sensitive neurostimulation | ||
The participation of the patient is essential and information will have been made during the anaesthesia consultation. It will be necessary to seek a response of the rytming dysesthesias by the frequency of nervestimulator, in the selected territory or in the middle of the surgical act. To the level of the pterygopalatine fossa, to the exit of the foramen rotundum, the maxillary nerve gives its terminal branches in a divergent nervous bouquet; the needle will position on one of its branches to dirige the injection and to thus seek the answer adapted to this nervous root. |
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For a complete block, one needs a central answer, or superior alveolar nerve (dysesthesias on the teeth), or infraorbital nerve (dysesthesias on the upper lip). With the injection the dysesthesias stop immediately. One will inject 0,1 ml.Kg-1 on average very slowly, of anaesthetic solution. The territory supplies by the maxillary block, when the block is complete is:
The success is higher than 80% for a complete block with a traditional technique; thus in a series of 58 blocks [21] one notes a success of 84% (for a maxillary surgery). The technique with neurostimulation allows a higher success rate (> 95% in our personal experiment). Nevertheless a defect in a territory can be corrected by troncular peripheral block, branches of the maxillary nerve (infra-orbital, zygomatic, palatine). Many indications for the maxillary block, in surgery: acts on the lower eyelid, the nose (with the nasal nerve), the cheek, the zygomatic area, the lower lip; superior dental surgery and acts on the palatine zone; and also the maxillary bone surgery, in complement of a general anaesthesia or used alone [22, 23]. In emergency, for the maxillary bone surgery and the wounds of the face (inferior eyelid, upper lip). The other indications gather those for postoperative analgesia; especially of bone maxillary surgery, but also the surgery of the tumours of the face. An indication, which starts to emerge, is the treatment of the pain of the maxillary zone, pain rebellious with other analgesics. One can then construct either a long duration block, or a perineural catheter with discontinuous injections of 0.2% ropivacaïne (see further). A maxillary block know-zygomatic guided by scanner was described in the treatment of the trigeminal neuralgias [23]. This block is paradoxically not painful: sedation can be necessary however, except in the neurostimulation. Except the failure few serious complications are described: on the same series [21] of 58 blocks, one notes 8 complications, regressive cephalgias, facial paralysis, a limitation of opening of mouth and a haematoma. Stimulation is certainly a reducing element of the potential complications, but which remains to be validated (in our experiment on 20 blocks in sensitive stimulation, not particular complication). Other techniques are described; an initially infrazygomatic approach [6, 7, 25], but it is of more difficult realisation, exposing to the vascular risk of breach and other rarer but more serious complications [7]. In the event of incomplete block, an additional block is completely realisable on the level
Infraorbital nerve block |
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 Movie of infraorbital block 1  |
Movie of infraorbital block 2 |
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| The infraorbital nerve leaves by the infraorbital foramen located at 4 -7 mm below the infra-orbital bone edge [18], before its exit, it gives the anterior superior alveolar nerve. It is appeared as a large nervous plexus [18] accompanied by its artery, and gives here its terminal branches. |
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The material for performing this block is an intradermal needle (26 G 5/8, 16 mm) connected to a syringe luer lock by an extension cable; or a needle with court bevel of 25 mm (24 G), standard neurostimulation needle. A cutaneous pen marker. The infraorbital block is performed frequently.The infraorbital foramen is located with the finger (marked with the pen), the point of puncture is done on the level of the lateral edge of the infraorbital foramen, while trying not to wound the nervous branches, classically with the balance of the centered pupil [7]. |
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The needle will seek the bone contact (with less than 10 mm generally) at the edge of the foramen, with a cephalic and medial direction. It is necessary to avoid the penetration of the foramen at all costs, causes nervous traumatism [19]: by palpating permanently the foramen [6]. The axis of the infraorbital foramen look towards the ala of the nose, also it is better to prick with a needle directed towards the root of the nose. Another approach can be done with introduction of the needle to the level of the nasal ala and with cephalic and lateral direction [6, 7, 18]. A sensitive neurostimulation is possible: with dysesthesias on the level of the upper lip or nose ala will then be sought. The injection
will be very slow with 2,5 to 3 ml of anaesthetic solution, in a
medial direction (or lateral in the other approach). After the shrinking
of the needle a discrete massage supports the diffusion of the product. The infraorbital block is a block with a very high success quasi 100% for some [18]; is an easily accessible superficial block for everybody, very much used by accustomed. Stimulation remains on this level only anecdotic. The main indications in surgery are: all acts on the lower eyelid, the upper lip, the cheek, the nose (with the nasal nerve and the supratrochlear nerve). In emergency, multiple wounds of the face in the maxillary tegumental zone. The other indications are dominated by postoperative analgesia, or for certain infraorbital neuralgia. The cutaneous puncture and the bone contact are sensitive: sedation can be necessary. The puncture of the infraorbital artery is exceptional and would mean quasi-nervous puncture. To reject the injection in the foramen source of complications [6,7,18]. They are especially sequels paraesthesias due to an oedema of the nerve strangled in its foramen directly related to a traumatic cause [7]. It was noted a transitory paralysis of the extrinsic muscles of the ocular sphere by orbital passage of the anaesthetic solution [1]. There is two other infraorbital approach [6,7]:
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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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