Lumbar sympathectomy. Stellate ganglion blockade. Coeliac plexus block. Splanchnic nerve block, страница 9

Thoracic and T6-T8 4-6 ml 5-10 ml/h

upper

abdominal

Lower T10 10ml 15 ml/h

abdominal

Hip or knee L2-3 8ml 10 ml/h

replacement

The initial bolus dose should be given at the end of surgery and the infusion started soon thereafter. If the block wears off, another bolus of 0.597o bupivacaine should be given and the infusion rate increased.

Table 220:2.

Morphine	0.5mg/h
Diamorphine	0.5mg/h
Pethidine	10mg/h
Fentanyl	10ug/h
Alfentanil	50 ug/h

Recommended infusion rate of opioids if added to 0.125 % bupivacaine. The opioid is added direct to the bupivacaine, the dose depending on the rate of infusion - see Table 220:1..

Spinal anaesthesia (see p. 194)

Continuous spinal anaesthesia using a catheter technique is gaining in popularity. Although it can involve piercing the dura with an 18 gauge needle, the incidence of spinal headache is surprisingly low, possibly due to the fact that most patients are elderly.

The advantage of the technique is that only very small quantities of local anaesthetic are required for each injection, eliminating unusually high blocks and the danger of toxicity.

Until there are further data on continuous infusions, the method of choice is repeated bolus injection. The amount given, the baricity of the solution and the position of the patient will be determined by the site of operation and the ability to position the patient appropriately. Thus following a hip operation, a patient who is sitting up may be given 0.75-1.5 ml of hyper-baric solution, while one who is nursed horizontal would do better with 0.75-1.5 ml of iso-baric or hypobaric solution. The extent and effectiveness of the block should be determined 20-30 min after the initial injection and appropriate modification to the dose made if necessary. Full aseptic precautions must be taken, particularly the use of a bacterial filter attached to the catheter.

Spinal opioids

Opioids injected into the cerebrospinal fluid are much more rapid in their onset than those used epidurally, and the dose required is about 10- 20% of the epidural dose. The incidence of respiratory depression is much higher than with epidural administration and the method cannot be recommended outside intensive care units. Even in such units the possibility of late respiratory depression and apnoea requires constant vigilance.

Conclusion

Much more could be done for patient comfort after operation if regional anaesthetic technique were more widely used, even with operations performed under general anaesthesia. Many of these techniques can be quickly and easily performed and pose little or no risk to the patient. The more complex methods require more dedication and particularly the cooperation and enthusiasm of an informed nursing staff.

221

Suggested further reading

Scott D.B. (1988). Management of acute pain. In Neural Block-• ade, eds. Cousins, M.C. and Bridenbaugh, P.O. Lippincott, Philadelphia, p. 861.

Index

acute generalised toxicity 176 adhesive arachnoiditis 26 advantage of regional anaesthesia 12 amide linkage 15

anterior spinal artery syndrome 26 arterial __

pressure 15 """

puncture 98 arthroscopy 40,216 atropine 197 autonomic system 166 axillary brachial plexus block 100

B

bacterial filter 172

baricity 196

blood loss '15

brachial plexus block 90, 217

bVonchoscopy 34

bupivacaine 19, 22, 191

C

CFS 192, 194

leakage 176 CNS toxicity 22 cardiovascular toxicity 22 catheter migration 217

technique 172

site 218 caudal block 182

in paediatric surgery 186 central nerve block 217 central nervous system toxicity 22 cervical epidural block 177 cervical plexus block 74 chloroprocaine HCI 19 cinchocaine (Dibucaine) 191 coeliac plexus block 210

combination of local anaesthetic and opioid 219 common peroneal nerve 130 complication 24, 52, 175, 197, 208, 210, 219 concomitant general anaesthesia 14 ,

conjunctiva 82 conscious patient 13 continuous spinal anaesthesia 194

D

deep peroneal nerve block 136 digital nerve block of the finger 114