The management of pain,both acute and chronic (generally more than 6 weeks),has evolved in many ways over the last few decades. Changes have not only occurred because of availability of new drugs ,and operative techniques, but also by virtue of a better understanding of the nature of pain itself. Two major types of pain are recognised:(i)Nociceptive:due to acute and active tissue trauma and inflammation-e.g. post -operative, appendicitis : and, (ii) Neuropathic-pain which persists long after the trauma or inflammation has passed ,and involving the nerves themseves-e.g.diabetic or post-herpetic neuropathic pain,intra-operative nerve root trauma, post-CVA pain, post spinal cord or post amputation pain.These are 2 very different types of pain-both aetiologically but also in terms of character AND treatment options.In clinical practice they are often confused and labelled incorrectly-but the differences are essential-presence or absence continuing trauma and atual nerve root/cord/brai distribution.Back pain after a laminectomy is not neuropathic -it is nociceptive.The treatment is different to managing nerve root pain or post root injury pain.In this article post-operative nociceptive pain will be reviewed.
Over the last few decades the importance of ADEQUATE post-operative pain management has been recognised-not the least cause being humanitarian.With better pain control in hospital and after discharge, the patient outcomes improve.They mobilise earlier, reduce pneumonia, DVTs, deconditioning and depression and bladder and bowel function is less impaired.There was a tendecy in the "olden days" to keep analgesia "to a minimum".Looking back on this medical and nursing teaching paradigm was to avoid sedation, fear of addiction and risk of overdosing the patient.These were reasonable concerns, and still are ,but nowadays with improvements in medications, education and monitoring equipment and protocols there has been improvent in pain control without compromising these other concerns.
It is widely recognised thet providing adequate analgesia commences during the spinal operation.Anaesthetists administer narcotics, steroids and IV paracemaol in theatre. The surgeon infiltrates the wound with long-acting local anaesthetics e.g. bupivicaine and adrenaline.The surgeon minimises tissue trauma and irrigates the wound with at least a litre of warm Ringer's Solution to disperse mediators of inflammation. Some surgeons utilise a post-operative epidural narcotic injection ,or infusion.Other units may infiltrate narcotics or local anaesthetic around the exposed nerve root.Early use of post-operative IV narcotic infusion is almost universal-either patient controlled (PCA) or constant for a day or two depending on circumstances.
Narcotic infusions are effective but do carry side-effects and risks.The patient must be closely monitored.There is a place for starting baseline oral regular analgesia on day one post-op.I have used paracetamol and dextropropoxyphene 2 QID from day 1 and continued for first 2 weeks after discharge for over a decade.
Dextropropoxyphene will not be available from March 2012.Alternatives will be paracetamol 2 Q6H or paracetamol and codeine (8 mg) 2 Q6H from day 1 regular and continue for first 2 weeks after discharge (with stool softeners).This will provide a "baseline" or "background" level of pain relif after painful spinal surgery.We all recognise the for a 2 to 3 week period of anticipated nociceptive moderate to severe level of pain that waiting until pain is "10/10" then giving a strong analgesic (e.g IM morphine/pethidine or oral oxycodone,for example)is sometimes ineffective.
After the narcotic infusion comes down on 2nd or 3rd post-operative day and the patient has had a day or two of paracetamol+-codeine regularly then EITHER oral oxycodone 5-10 mg Q6h OR IM pethidine or morphine PRN can be utilised for SEVERE pain episodes( "breakthrough pain") until the patient is able to be discharged. At home regular 2 Q6H and PRN oxycodone 5-10 mg Q6H( for "breakthrough "pain not controlled by the "baseline" regular paracetamol+/- codeine) may be prescribed during the first 2 weeks at home.Thereafter PRN paracetamol +/-codeine 2 Q6H should be sufficient in most cases.
There are some units that use NSAIDs /COX inhibitors or Tramadol (an S4 narcotic) -I have used these as well.The NSAIDs and COX inhibitors have significant risks-GI bleed, MI etc and Tramadol can cause nausea and confusion, particularly in the elderly.That being said, paracetamol , codeine, pethidine/morphine and oxycodone ALSO have risks ,and benefits of their own and require care and monitoring.The prescriber needs to be familiar with their use over a number of years.Each patient also requires a review of their own particular requirements.
Every spinal surgical unit surgeon and nurse will have their own post-spinal surgical pain management protocol and if it works with acceptable side-effects profile then that is satisfactory.We are all surgically "moulded" by our own experiences with our years of surgery, complications,medication efficacy and side-effects over the decades and form our own individual practices, and biases!