CERVICAL EPIDURAL-ANESTHESIA

Cervical epidural anaesthesia (CEA) results in an effective sensory bl ockade of the superficial cervical (C1/C4) and brachial plexus (C5/T1- T2). It is used both intraoperatively and in the treatment of postoper ative or chronic pain. The approach to the epidural space at the C7-T1 interspace is not technically difficult. Patients are placed in the s itting position, increasing the negative pressure in the epidural spac e, with the head flexed on the thorax, in order to open the lowest cer vical interspace. A 18-gauge Tuohy needle is inserted by a midline app roach into the C6-C7 or C7-T1 interspace. A catheter may be inserted a nd left in place for postoperative analgesia. Local anaesthetics are a dministered either alone, or in combination with opiates. The CEA bloc ks the cardiac sympathetic fibers and consequently decreases heart rat e, cardiac output and contractility. The mean blood pressure is unchan ged or decreased, depending on periphereal systemic vascular resistanc e changes. The baroreflex activity is also partly impaired. Sympatheti c blockade also decreases myocardial ischaemia. The cardiovascular cha nges induced by CEA are also partly due to the systemic effect of the local anaesthetic. The respiratory effects are minimal and depend on t he extent of the blockade and the concentration of the local anaesthet ic. A moderate restrictive syndrome occurs. Since the phrenic nerves o riginate from C3 to C5, ventilation may be impaired by CEA. Extension of the block may also impair intercostal muscle function, with a risk of respiratory failure when a CEA is used in patients with compromised respiratory function. The potential specific complications, mainly ca rdiovascular and respiratory, are the exacerbation of the effects of C EA. Side effects such as bradycardia, hypotension and acute ventilator y failure in relation to respiratory muscle paralysis, may be observed . Close monitoring of haemodynamics, respiratory rate and level blocka de is required. Cervical epidural anaesthesia, may be used either alon e, or in combination with general anaesthesia depending on the surgica l procedure. This technique seems to be effective in carotid artery su rgery since sensitive and reliable information on cerebral function ma y- be obtained. It is also for shoulder and upper limb surgery as well as for pharyngolaryngeal surgery, providing efficient operative anaes thesia and postoperative analgesia. CEA is used for relief of chronic pain in the head and neck or cancer pain due to Pancoast-Tobias syndro me. It seems to be effective for treating pain in patients with unstab le angina pectoris or acute myocardial infarction.