***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: AIM Epidural analgesia is considered to be the best method of pain relief after major surgery despite its side-effects , which include hypotension , respiratory depression , urinary retention , incomplete or failed block , and , in rare cases , paraplegia . Paravertebral block is an alternative technique that may offer a comparable analgesic effect and a better side-effect profile . This study measured postoperative pain and respiratory function in patients r and omized to receive either paravertebral block or epidural analgesia for pain control after thoracic surgery . METHODS Twenty-four adult patients undergoing thoracic surgery were enrolled in a prospect i ve and r and omized clinical study . Patients were r and omly allocated to receive either postoperative continuous paravertebral analgesia ( N=12 ) or epidural analgesia ( N=12 ) starting at pleura closure . Postoperative use of morphine , visual analogue scores , and spirometer data were collected for 72 hours after surgery as markers of pain relief . RESULTS There was a statistically significant ( P=0.003 ) increase in median ( 25th-75th percentiles ) patient-controlled use of morphine , with values of 36 ( 22 - 42 ) mg in the paravertebral group vs. 9 ( 2 - 22 ) mg in the epidural group . This increase in morphine usage in the paravertebral group was statistically significant at 6 , 24 , 48 , and 72 hours after surgery . Postoperative pain measured with the visual analogue score was not significantly different in the two groups . Spirometer values at 72 h were better in the epidural group than in the paravertebral group ( P=0.03 ) . CONCLUSIONS Epidural analgesia is more efficient than paravertebral continuous block at reducing pain after thoracic surgery OBJECTIVE To compare the results of continuous epidural bupivacaine analgesia with and without hydromorphone to continuous paravertebral analgesia with bupivcaine in patients with post-thoracotomy pain . DESIGN A prospect i ve , r and omized , double-blinded trial . SETTING A teaching hospital . PARTICIPANTS Patients at a tertiary care teaching hospital undergoing throracotomy for lung cancer . INTERVENTIONS Subjects were assigned r and omly to receive a continuous thoracic epidural or paravertebral infusion . Patients in the epidural group were r and omized to receive either bupivacaine alone or in combination with hydromorphone .  Visual analog scores as well as incentive spirometery results were obtained before and after thoracotomy . METHODS AND MAIN RESULTS Seventy-five consecutive patients presenting for thoracotomy were enrolled in this institutional review board-approved study . On the morning of surgery , subjects were r and omized to either an epidural group receiving bupvicaine with and without hydromorphone or a paravertebral catheter-infused bupvicaine .  Postoperative visual analog scores and incentive spirometry data were measured in the postanesthesia care unit , the evening of the first operative day , and daily thereafter until postoperative day 4 . Analgesia on all postoperative days was superior in the thoracic epidural group receiving bupivacaine plus hydromorphone .  Analgesia was similar in the epidural and continuous paravertebral groups receiving bupivacaine alone . No significant improvement was noted by combining the continuous infusion of bupivacaine via the paravertebral and epidural routes . Incentive spirometry goals were best achieved in the epidural bupivacaine and hydromorphone group and equal in the group receiving bupivacaine alone either via epidural or continuous paravertebral infusion . CONCLUSIONS The current study provided data that fill gaps in the current literature in 3 important areas . First , this study found that thoracic epidural analgesia ( TEA ) with bupivacaine and a hydrophilic opioid , hydromorphone , may provide enhanced analgesia over TEA or continuous paravertebral infusion ( CPI ) with bupivacaine alone . Second , in the bupivacaine-alone group , the increased basal rates required to achieve analgesia result ed in hypotension more frequently than in the bupivacaine/hydromorphone combination group , underscoring the benefit of the synergistic activity . Finally , in agreement with previous retrospective studies , the current data suggest that CPI of local anesthetic appears to provide acceptable analgesia for post-thoracotomy pain Background : The aim of this prospect i ve , r and omized , blinded study was to compare analgesic efficacy of continuous paravertebral and epidural analgesia for  post‐thoracotomy pain . Methods : Forty‐two ASA physical status II – III patients undergoing lung resection surgery were r and omly allocated to receive post‐thoracotomy analgesia with either a thoracic epidural ( group EPI , n = 21 ) or paravertebral ( group PVB , n = 21 ) infusion of 0.2 % ropivacaine ( infusion rate : 5–10 mL h−1 ) . The degree of pain at rest and during coughing , haemodynamic variables and blood gas analysis were recorded every 12 h for the first 48 h. Results : The area under the curve of the visual analogue pain score during coughing over time was 192 ( 60–444 ) cm h−1 in group EPI and 228 ( 72–456 ) cm h−1 in group PVB ( P = 0.29 ) . Rescue morphine analgesia was required in four patients of group EPI ( 19 % ) and five patients of group PVB ( 23 % ) ( P = 0.99 ) . The PaO2/FiO2 ratio reduced significantly from baseline values in both groups without between‐group differences . The median ( range ) percentage reduction of systolic arterial pressure from baseline was −9 ( 0 to −9)% in group PVB and −17 ( 0 to −38)% in group EPI ( P = 0.02 ) ; while clinical ly relevant hypotension ( systolic arterial pressure decrease > 30 % of baseline ) was observed in four patients of group EPI only ( 19 % ) ( P = 0.04 ) . Patient satisfaction with the analgesia technique was 8.5 ( 8–9.8 ) cm in group EPI and 9 ( 7.5–10 ) cm in group PVB ( P = 0.65 ) . Conclusions : Continuous thoracic paravertebral analgesia is as effective as epidural blockade in controlling post‐thoracotomy pain , but is associated with less haemodynamic effects This study was undertaken to evaluate the effectiveness of 0.5 % bupivacaine ( 360 mg/day ) as a continuous infusion through an indwelling intercostal catheter inserted intraoperatively in the management of pain after thoracotomy . Eighty-six patients were r and omized into three groups : group 1 = intercostal bupivacaine , group 2 = intercostal saline solution , and group 3 = fixed-schedule intramuscular buprenorphine . Supplementary buprenorphine was given as required . Pain and pulmonary function were assessed throughout the first 5 days after operation . Pain score was lower in group 1 than in group 2 for the first 8 hours after operation ( p < 0.02 ) . During the first 3 postoperative days , mean postoperative pain scores of 5 or more were recorded in 9 % of group 1 patients versus 40 % of group 2 patients ( p < 0.05 ) and 13 % of group 3 patients ( not significant ) . Total doses of buprenorphine  were lower in groups 1 and 2 than in group 3 ( p < 0.001 ) . No between-group differences in pulmonary function were observed . Respiratory complications occurred in no patients in groups 1 and 3 versus 5 in group 2 ( p < 0.05 ) . Continuous intercostal bupivacaine provided similar early pain control as compared with fixed-schedule narcotics but induced better analgesia with fewer complications than on-dem and narcotics alone ( group 2 ) Context Thoracic epidural and paravertebral blocks provide adequate analgesia for postoperative thoracotomy pain . Both procedures are usually performed percutaneously with considerable failure rates . A subpleural catheter placed in the space posterior to the parietal pleura and alongside the paravertebral area may provide superior postoperative pain relief . Objective To compare subpleural analgesia with thoracic epidural analgesia in patients undergoing thoracotomy . Design R and omised , double-blind study . Setting A tertiary care University Medical Centre between 26 June 2008 and 21 March 2011 . Patients Forty-two patients scheduled for elective posterolateral thoracotomy . Patients with American Society of Anesthesiologists physical status ≥4 , with a previous history of thoracotomy , on chronic pain medications or with a contraindication to receiving local anaesthetics or thoracic epidural block were excluded from the study . Interventions Patients were r and omised to receive either subpleural analgesia or thoracic epidural analgesia for 24-h post-thoracotomy pain control . Main outcome measures A visual analogue scale was used to assess pain at rest and on coughing during the first 24 h postoperatively and the incidence of hypotension was recorded . Results Patients who received subpleural analgesia had higher visual analogue scores at rest and on coughing than those who received thoracic epidural analgesia . Seven patients who started with subpleural analgesia were treated with thoracic epidural analgesia at a mean ( SD ) of 3.9 ( 4.8 ) h. The remaining 14 patients had a median ( IQR [ range ] ) visual analogue score of 5 cm ( 4–5 [ 3–6 ] ) at rest and were maintained on subpleural analgesia until the end of the study . The visual analogue score at rest was < 7 cm in all 21 patients who received thoracic epidural analgesia and none was switched to subpleural analgesia during the study . None of the patients in the subpleural analgesia group experienced hypotension compared with five of the 21 patients in the thoracic epidural analgesia group ( P = 0.047 ) . Conclusion Thoracic epidural analgesia is superior to subpleural analgesia in relieving post-thoracotomy pain Background In order to assess the short term risks of pneumonectomy for lung cancer in contemporary practice a one year prospect i ve observational study of pneumonectomy outcome was made . Current UK practice for pneumonectomy was observed to note patient and treatment factors associated with major complications . Methods A multicentre , prospect i ve , observational cohort study was performed . All 35 UK thoracic surgical centres were invited to su bmi t data to the study . All adult patients undergoing pneumonectomy for lung cancer between 1 January and 31 December 2005 were included . Patients undergoing pleuropneumonectomy , extended pneumonectomy , completion pneumonectomy following previous lobectomy and pneumonectomy for benign disease , were excluded from the study .The main outcome measure was suffering a major complication . Major complications were defined as : death within 30 days of surgery ; treated cardiac arrhythmia or hypotension ; unplanned intensive care admission ; further surgery or inotrope usage . Results 312 pneumonectomies from 28 participating centres were entered . The major complication incidence was : 30-day mortality 5.4 % ; treated cardiac arrhythmia 19.9 % ; unplanned intensive care unit admission 9.3 % ; further surgery 4.8 % ; inotrope usage 3.5 % . Age , American Society of Anesthesiologists physical status ≥ P3 , pre-operative diffusing capacity for carbon monoxide ( DLCO ) and epidural analgesia were collectively the strongest risk factors for major complications . Major complications prolonged median hospital stay by 2 days . Conclusion The 30 day mortality rate was less than 8 % , in agreement with the British Thoracic Society guidelines . Pneumonectomy was associated with a high rate of major complications . Age , ASA physical status , DLCO and epidural analgesia appeared collectively most associated with major complications BACKGROUND Optimal management of pain after thoracotomy can be challenging . Continuous infusion of local anesthetic into the incision may help reduce the amount of narcotics required to control postoperative pain . To address this issue , we performed a r and omized , double-blinded , controlled trial of infusion of bupivacaine versus placebo through intercostal and subcutaneous catheters after thoracotomy . METHODS From April 2006 to June 2007 , 124 patients had intercostal catheters placed at thoracotomy  and connected to continuous infusion pain pumps . Each patient had catheters placed in the intercostal space near the head of the rib and subcutaneously beneath the incision ; both were connected to an infusion pump through a Y connector . Patients were r and omly assigned to receive placebo ( normal saline solution ) or 0.25 % bupivacaine as a 4 cc per hour infusion for 100 hours after thoracotomy . All personnel caring for the patients were blinded to the content of the infusion . Demographic information , visual analog pain scores , and oral morphine equivalent usage was recorded for each patient . In addition to the infusion catheters , all patients had epidural analgesia that remained in place until postoperative day 3 . RESULTS There were 60 patients in the bupivacaine arm and 64 in the placebo group . Overall mean age was 64.7 years and 65 ( 52.4 % ) were men . Mean body mass index was 28.8 kg/m(2 
    Output:
    
So , we conclude that thoracic PVB may be as effective as thoracic epidural analgesia for post-thoracotomy pain relief and is also associated with fewer complications