Levobupivacaine

During epidural administration of levobupivacaine, concentrated solutions (0.5-0.75%) should be administered in incremental doses of 3 to 5 ml with sufficient time between doses to detect toxic manifestations of unintentional intravascular or intrathecal injection. Cases of severe bradycardia, hypotension and respiratory compromise with cardiac arrest (some of them fatal); have been reported in conjunction with local anaesthetics, including levobupivacaine. When a large dose is to be injected, e.g. in epidural block, a test dose of 3-5 ml lidocaine with adrenaline is recommended. An inadvertent intravascular injection may then be recognised by a temporary increase in heart rate and accidental intrathecal injection by signs of a spinal block.

Syringe aspirations should also be performed before and during each supplemental injection in continuous (intermittent) catheter techniques. An intravascular injection is still possible even if aspirations for blood are negative. During the administration of epidural anaesthesia, it is recommended that a test dose be administered initially and the effects monitored before the full dose is given.

Epidural anaesthesia with any local anaesthetic may cause hypotension and bradycardia. All patients must have intravenous access established. The availability of appropriate fluids, vasopressors, anaesthetics with anticonvulsant properties, myorelaxants, and atropine, resuscitation equipment and expertise must be ensured.

The patient should have I.V. fluids running via an indwelling catheter to assure a functioning intravenous pathway. The lowest dosage of local anaesthetic that results in effective anaesthesia should be used to avoid high plasma levels and serious adverse effects. The rapid injection of a large volume of local anaesthetic solution should be avoided and fractional (incremental) doses should be used when feasible.

Clinicians who perform retrobulbar blocks should be aware that there have been reports of respiratory arrest following local anaesthetic injection. Prior to retrobulbar block, as with all other regional procedures, the immediate availability of equipment, drugs, and personnel to manage respiratory arrest or depression, convulsions, and cardiac stimulation or depression should be assured. As with other anaesthetic procedures, patients should be constantly monitored following ophthalmic blocks for signs of these adverse reactions.

Small doses of local anaesthetics injected into the head and neck area, including retrobulbar, dental and stellate ganglion blocks, may produce adverse reactions similar to systemic toxicity seen with unintentional intravascular injections of larger doses. The injection procedures require the utmost care. Reactions may be due to intraarterial injection of the local anaesthetic with retrograde flow to the cerebral circulation. They may also be due to puncture of the dural sheath of the optic nerve during retrobulbar block with diffusion of any local anaesthetic along the subdural space to the midbrain. Patients receiving these blocks should have their circulation and respiration monitored and be constantly observed. Resuscitative equipment and personnel for treating adverse reactions should be immediately available.

There have been post-marketing reports of cauda equina syndrome and events indicative of neurotoxicity temporally associated with the use of levobupivacaine for 24 hours or more for epidural analgesia. These events were more severe and in some cases led to permanent sequelae when levobupivacaine was administered for more than 24 hours. Therefore, infusion of levobupivacaine for a period exceeding 24 hours should be considered carefully and only be used when benefit to the patient outweighs the risk.

It is essential that aspiration for blood or cerebrospinal fluid (where applicable) be done prior to injecting any local anaesthetic, both before the original dose and all subsequent doses, to avoid intravascular or intrathecal injection. However, a negative aspiration does not ensure against intravascular or intrathecal injection. Levobupivacaine should be used with caution in patients receiving other local anaesthetics or agents structurally related to amide-type local anaesthetics, since the toxic effects of these drugs are additive.

Continuous epidural infusion, single or multiple bolus epidural administration for the management of pain especially labour analgesia.