Conference Lectures

Post-Thoracotomy Pain Relief
Dr ChaitaliSenDasgupta, MD,DNB,DM(Cardiac Anaesthesia), MNAMS
Associate Professor, Department of Cardiac Surgery, I.P.G.M.E &R, Kolkata


Thoracotomy causes severe pain in the post operative period, probably it is the most severe postoperative pain. The post-thoracotomy pain so severe because, thoracotomy involves injury to skin,multiple  muscles, ligaments, vessels,intercostals nerves as well as ribs. The intercostals chest drain also adds fuel to the fire as they are not only painful while they are in situcausing pleural irritation, but also causes pain while  they are being removed. The pain after thoracotomy must be ameliorated because due to pain the patient refuses to cough, which causes accumulation of secretions in the alveoliresulting in atelectasis, ventilation perfusion mismatch, hypoxaemiawith deterioration of respiratory function leading to prolonged ventilator requirement and respiratory failure. It may alsoleadto chronic post-thoracotomy pain syndrome in the long run.
Respiratory function may be improved by effective analgesia enabling the patient to cough and other deep breathing exercises including incentive spirometry, with increased removal of accumulated secretions. Effective analgesia also decreases patient discomfort and stress response. So, proper analgesia is one  of the main determinant of postoperative outcome  for thoracotomy patients by maintainence of  their functional residual capacity by deep breathing.On the other hand, inadequate pain relief may lead to chronic postoperative pain syndrome.
The available treatment options for post-thoracotomy pain are thoracic epidural analgesia, lumber epidural analgesia,paravertebral block, intercostal nerve blocks,intrapleural  analgesia,TENS therapy, cryoanalgesia, intravenous and intrathecal opioids, NSAIDS and so on.

Thoracic epidural analgesia: -Thoracic epidural analgesia is usually performed by midline or paramedian approach at T3-T6 level before general anaesthesia. Usually paramedian approach is easier in thoracic epidural than lumber epidural. After the test dose of lignocaine, either local anaesthetic alone or combination of local anaesthetic with opioid is given through the epidural catheter before incision.Intraoperatively, either continuous infusion or bolus of local anaesthetic with or without opioid is administered. Postoperatively, intermittent bolus or continuous infusion or patient controlled epidural analgesia is continuedfor another 48-72 hours Among local anaesthetic, bupivacaine or levobupivacaine or ropivacaine is important. Quality of analgesia depends on the total dose administered rather than volume and concentration.1Among opioids, lipophilic opioids like fentanyl is preferred than hydrophilic opioids like morphine because of incidence of respiratory depression with the later. Epidural opioids may cause respiratory depression and hypotension apart from nausea, vomiting, pruritus and urinary retention. In case of patients receiving low molecular weight heparin (LMWH), the epidural hematoma may extend causing neurological disaster. LMWH may be given 2 hours after removal of epidural catheter and 10-12 hours after last dose of LMWH while epidural catheter may be inserted after 12 hrs of thromboprophylaxis by LMWH and 24 hours of high therapeutic dose of LMWH2,3.
In a study of one hundred and twenty patients following thoracotomy,SagirogluG et al concluded  that, patient controlled thoracic epidural analgesia was more effective than patient controlled lumber epidural analgesia with 0.125% bupivacaine with sufentanylwhile controlling pain after thoracotomy4.

Paravertebral Block:- By paravertebral block, both dorsal and ventral ramii of spinal nerves are anaesthetised. For thoracic surgery, T4to T7 dermatomes are to be blocked. It may be given in patients where epidural analgesia is contraindicated. As it causes unilateral analgesia, so it may be well utilised after thoracotomy.The main advantage of paravertebral block over epidural analgesia is that, incidence of hematoma, neurological complications, hypotension(because of unilateral blockade), pleural puncture, pneumothorax urinary retention etc are lower5. Local anaesthetics like bupivacaine, levobupivacaine or ropivacaine  with or without opioids are usually used as bolus before incision followed by intermittent bolus or continuous infusion.

Intercostal Block:-Two spaces above and below the incision line are to be blocked by this method.Complications  are very rare after this procedure and it may be given even in patients with coagulation abnormalities5. But, sometimes,if dural sheath is extended 8 cm laterally, then, high and rapid absorbtion of local anaesthetic may lead to spinal anaesthesia6.

Intrapleural Analgesia:- Local Anaesthetic is injected in the pleural space by a catheter usually inserted during surgery. But its effect is controversial as most of the drug is either wasted by the drainage tubes or accumulated in the costophrenic angle. High absorbtion of local anaesthetic may also cause systemic toxicity5.

Cryoanalgesia: This is done by a small needle called  cryoprobe; a hollow tube with a smaller inner tube. Either liquid carbon dioxide or nitrous oxide is releasedfrom the cryoprobe under high pressure and expands into the tip. The work done by the gas as it expands results in a temperature drop Temperatures is -70oC.  In a metaanalysis of forty studies using cryoanalgesia after thoracotomy, the authors concluded that, it should not be used as a sole method of choice for post thoracotomy pain relief.6
Intravenous Drugs: -NSAIDs, clonidine, opioids etc are being used for post-thoracotomy pain relief  as intravenous bolus or patient controlled analgesia.

Shoulder pain:-Many patients complain of ipsilateral shoulder pain. This is probably due to referred from phrenic nerve along with effect of positioning during surgery. It is not usually  relieved by intravenous opioids and partially relieved by NSAIDs9,  low-volume interscalene brachial plexus block7 or intraoperative unilateral phrenic nerve block.8

Chronic Post-Thoracotomy Pain(PTPS):-Pain which persists atleast two months after thoracotomy is called PTPS.It is a burning and stabbing pain comparable to neuropathic pain.9The causes of PTPS is varied from intercostals nerve damage, type of incision and different personality traits10.

TENS:-Here,stimulii are administered through flat electrodes applied to skin and the stimulator provide low intensity frequency of 5-200Hz.It produces tingling sensation and more effective for chronic pain by reducing cytokine production11.

A systematic review of regional analgesia following thoracotomy (study period 1966-2004) concluded thoracic epidural analgesia to be the most effective method for controlling the  post thoracotomy pain. They also concluded that thoracic paravertebral block to be as effective as thoracic epidural analgesia with local anaesthetic alone, but more studies are required to compare paravertebral block with epidural analgesia when epidural opioids are being used.According to them, all other regional techniques specially intrapleural analgesia do not provide any analgesia. They suggested, intercostal nerve block or preoperative intrathecal opioid only when thoracic epidural or paravertebral techniques are not possible or are contraindicated12.
Conclusion:- A multimodal approach is now considered best while thoracic epidural remains the Gold Standard for post operative pain relief after thoracotomy5.

References:-

Dernedde M, Stadler M, Bardiau F, Boogaets J. Comparison of different concentration of levobupivacaine for postoperative epidural analgesia. ActaAnaesthesiolScand 2003;47:884-90.

ASRA guidelines, 2003

  1. Horlocker T T.  Regional anaesthesia in the patient receiving antithrombotic and antiplatelet therapy. Br. J. Anaesth.2011; 107 (suppl 1): i96-i106.

Sagiroglu G,  Meydan B, Copuroglu E,Baysal A,3 Yoruk Y,4 Altemur Y et al  A comparison of thoracic or lumbar patient-controlled epidural analgesia methods after thoracic surgery. World J SurgOncol. 2014; 12: 96

Decosmo G, Aceto P., GualtieriE.Analgesia in thoracic surgery: reviewMinerva Anestesiol 2009;75:393-400

Khanbhaia M, Yapb K H,   Mohamed S, Dunningd.  Is cryoanalgesia effective for post-thoracotomy paiJ Interact CardioVascThorac Surg. 2014 18: 202-209.

Barak M1, Iaroshevski D, Poppa E, Ben-Nun A, Katz YLow-volume interscalene brachial plexus block for post-thoracotomy shoulder pain.J CardiothoracVascAnesth. 2007;21:554-7.

  1. Scawn ND, Pennefather SH, Soorae A, Wang JY, Russell GN. Ipsilateral shoulder pain after thoracotomy with epidural analgesia: the influence of phrenic nerve infiltration with lidocaine.AnesthAnalg. 2001 Aug; 93(2):260-4, 
  2. Koehler RP, Keenan RJ. Management of postthoracotomy pain: acute and chronic.ThoracSurgClin. 2006;16:287-97.
  1. Gerner P; Post-thoracotomy Pain Management Problems AnesthesiolClin. 2008; 26: 355–7
  2. Fiorelli A, Morgillo F, Milione R, Pace MC, Passavanti MB, Laperuta P, Aurilio C, Santini M; Control of post-thoracotomy pain by transcutaneous electrical nerve stimulation: effect on serum cytokine levels, visual analogue scale, pulmonary function and medication. Eur J Cardiothorac Surg. 2012;41:861-8;
  3. Joshi G P, Bonnet F, Shah R et al ,A systematic review of randomized trials evaluating regional techniques for post-thoracotomy analgesia. AnesthAnalg 2008;107:1026 –40