Intrapleural bupivacaine in the control of postthoracotomy pain

Injection of Bupivacaine into the Pleural and Mediastinal Drains: A Novel Approach for Decreasing Incident Pain After Cardiac Surgery - Montreal Heart Institute Experience

Background

We conducted a chart review of prospectively collected data in order to demonstrate the safety and efficacy of an innovative technique of pleural and mediastinal drain injections.

Methods

Patients who had undergone cardiac surgery and who continued to have pain despite the use of a multimodal pain protocol received injections of 20 mL of 0.25% bupivacaine in pleural and/or mediastinal chest drainage tubes.

Results

Patients were evaluated for the incidence mediastinitis, osteitis, and deep sternal wound infection as well as the speed and intensity of pain relief. The odds ratio of infection in the infused group was 0.955 (CI = 0.4705, 1.9384). The adjusted mean “decrease in pain” was 4.01 (SEM = 0.15 and 95% CI = 3.78, 4.38), using the 11-point Likert Numerical Rating Scale. The mean adjusted “time to maximum pain relief” was 8.33 minutes (SEM = 0.42 and 95% CI = 7.50, 9.15).

Conclusion

This technique is a powerful, safe, and efficient tool in the armamentarium of pain management and its growing use within our institution has provided a substantial benefit in the treatment of early post-operative pain.

Daring discourse: should the ESP block be renamed RIP II block?

During the time period 1984 to the turn of the millennium, interpleural nerve blockade was touted as a very useful regional anesthetic nerve blockade for most procedures or conditions that involved the trunk and was widely practiced despite the lack of proper evidence-based support. However, as an adequate evidence base developed, the interest for this type of nerve block dwindled and very few centers currently use it-thereby to us representing the rest in peace (RIP) I block. Unfortunately, we get a deja-vù sensation when we observe the current fascination with the erector spinae plane block (ESPB), which since 2019 has generated as many as 98 PubMed items. This daring discourse point out the lack of a proper evidence base of the ESPB compared with other established nerve blocking techniques as well as the lack of a proven mechanism of action that explains how this nerve block technique can be effective regarding surgical procedures performed on the front of the trunk. Emerging meta-analysis data also raise concern and give cause to healthy skepticism regarding the use of ESPB for major thoracic or abdominal surgery. Against this background, we foresee that ESPB (and variations on this theme) will end up in a similar fashion as interpleural nerve blockade, thereby soon to be renamed the RIP II block.

Optimal dose of ropivacaine for relieving cough-pain after video-assisted thoracoscopic lobectomy by single intrapleural injection: A randomized, double-blind, controlled study

BACKGROUND

Pain due to coughing after thoracoscopic surgery remains a clinical problem, and its relief by intrapleural analgesia has not been extensively studied. This study attempts to determine the suitable volume of 0.75% ropivacaine needed for intrapleural analgesia after thoracoscopic surgery.

METHODS

A double-blind, randomized, controlled trial was performed. Forty-five patients were randomly divided into three groups: R20, R15, and R10 (n = 15); 20 ml, 15 ml, or 10 ml of 0.75% ropivacaine was injected into the pleural cavity of each patient in the 3 groups, respectively, when the pain score from postoperative coughing was ≥4. The primary outcome was pain score upon coughing (C-NRS), and the secondary outcomes were pain score at rest (R-NRS), morphine consumption, time of onset, and duration of intrapleural analgesia.

RESULTS

All patients in the R20 and R15 groups reported effective pain relief after intrapleural injection when postoperative coughing occurred. However, only 7 patients in the R10 group reported effective relief of pain. Compared with the patients in the R10 group, patients in the R20 and R15 groups had lower C-NRS scores, less morphine consumption at 8 h and 24 h, a shorter time to pain relief, and a longer duration of analgesia. There was no significant difference of R-NRS among the three groups.

CONCLUSION

Intrapleural analgesia with 0.75% ropivacaine at a volume of 15 ml or 20 ml effectively relieved pain due to coughing after thoracoscopic surgery.

TRIAL REGISTRATION

ChiCTR1800017515.

Analgesia following Thoracotomy: A Survey of Australian Practice

This survey examines pain management after thoracotomy in Australian hospitals. Questionnaires were sent to senior thoracic anaesthetists at 27 hospitals (16 public and 11 private) with thoracic surgical units. Twenty-six anaesthetists replied and 24 responses were included in the analyses. Seventy-two percent of respondents were from hospitals with acute pain services (APS), and in 94% of these hospitals patients are reportedly visited by the APS. The most frequently used analgesic modalities are epidural analgesia, intravenous patient-controlled analgesia (IVPCA), and nurse-controlled intravenous opioid infusions. Over half of the anaesthetists reported using local anaesthetic intercostal nerve block, non-steroidal anti-inflammatory drugs (NSAIDs), or paracetamol. Combinations of analgesic techniques were cited frequently. Respondents reported that cryoanalgesia, interpleural blockade, paravertebral blockade, subarachnoid infusions, ketamine, and transcutaneous electrical nerve stimulation are used infrequently. Anaesthetists from public hospitals reported using epidural analgesia, IVPCA and NSAIDs more frequently than those from private hospitals. When epidural analgesia is used, most respondents place the catheter in the mid-thoracic region (91%), use a regimen of opioids plus local anaesthetic (96%), use a constant infusion technique (100%), and continue analgesia for up to three days (83%). Over half of the respondents reported that post-thoracotomy patients are nursed in a high-dependency area. Seventy-nine percent of respondents selected epidural analgesia as the best available analgesia technique, whereas 21% consider IVPCA to be the best. Only 75% of respondents reported that the type of analgesia they consider best is also the type which they use most frequently ‡ .

The effect of bilateral intrapleural infusion of lidocaine with fentanyl versus only lidocaine in relieving pain after coronary artery bypasses surgery

Background and Objective:

Pain control during surgery in order to cause analgesia and reduce the somatic and autonomic response may decrease the morbidity. Intrapleural catheter embedding during surgery under direct vision of surgeon is safe and easy and without potential risk of thoracic epidural block. The aim of this study was to investigate the effect of bilateral intrapleural infusion of lidocaine with fentanyl versus only lidocaine in relieving pain after coronary artery bypass surgery.

Methods:

In this prospective randomized double blind clinical trial,130 adult patients undergoing elective CABG with age range of 20 to 60 years were divided into two groups receiving either lidocaine and fentanyl (group A) or lidocaine (group B). The analgesia was evaluated every two hours in all intubated and non-intubated patients using Visual analog scale (VAS) and data were analyzed using SPSS software package.

Results:

Of all patients, 67 (51.5%) were males and 63 (48.5%) were females. The average age of subjects was 53.49 ± 5.099 years. Mean pain score six hours after the surgery was statistically different between the groups at all times.

Conclusion:

The pain in patients receiving combination of lidocaine and fentanyl is less than patients receiving only lidocaine.

Effectiveness of intercostal nerve block for management of pain in rib fracture patients

Controlling pain in patients with fractured ribs is essential for preventing secondary complications. Conventional medications that are administered orally or by using injections are sufficient for the treatment of most patients. However, additional aggressive pain control measures are needed for patients whose pain cannot be controlled effectively as well as for those in whom complications or a transition to chronic pain needs to be prevented. In this study, we retrospectively analyzed the medical records of patients in our hospital to identify the efficacy and characteristics of intercostal nerve block (ICNB), as a pain control method for rib fractures. Although ICNB, compared to conventional methods, showed dramatic pain reduction immediately after the procedure, the pain control effects decreased over time. These findings suggest that the use of additional pain control methods (e.g. intravenous patient-controlled analgesia and/or a fentanyl patch) is recommended for patients in who the pain level increases as the ICNB efficacy decreases.

Comparison of paravertebral and interpleural block in patients undergoing modified radical mastectomy

Background:

Paravertebral and inter pleural blocks (IPB) reduce post-operative pain and decrease the effect of post-operative pain on lung functions after breast surgery. This study was designed to determine their effect on lung functions and post-operative pain in patients undergoing modified radical mastectomy.

Materials and Methods:

A total of 120 American Society of Anesthesiologists physical status 1 and 2 patients scheduled to undergo breast surgery were randomly allocated to receive IPB (Group IPB, n = 60) or paravertebral block (PVB) (Group PVB, n = 60) with 20 ml of 0.5% bupivacaine pre-operatively. A standard protocol was used to provide general anesthesia. Lung function tests, visual analog scale (VAS) for pain at rest and movement, analgesic consumption were recorded everyday post-operatively until discharge.

Results:

Lung functions decreased on 1^st post-operative day and returned to baseline value by 4^th post-operative day in both groups. VAS was similar in both groups. There was no significant difference in the consumption of opioids and diclofenac in both groups. Complete block was achieved in 48 patients (80%) in paravertebral group and 42 patients (70%) in inter pleural group.

Conclusion:

To conclude, lung functions are well-preserved in patients undergoing modified radical mastectomy under general anesthesia supplemented with paravertebral or IPB. IPB is as effective as PVB for post-operative pain relief. PVB has the added advantage of achieving a more complete block.

Respiratory chest pain: diagnosis and treatment

Chest pain from respiratory causes is a common complaint and may indicate the presence of a serious or even life-threatening pathologic condition. Most chest pains are the result of irritation or inflammation of the parietal pleura, as the visceral pleura is insensate, although pain may arise from direct malignant invasion or trauma to the chest wall. Rapid recognition with appropriate understanding of the anatomy and physiology of chest pain from respiratory causes is vital to ensure timely and appropriate therapy.

Interpleural morphine vs bupivacaine for postthoracotomy pain relief

This prospective randomized double-blind trial was designed to compare the analgesic effects of interpleural bupivacaine and interpleural morphine for postthoracotomy pain management. Thirty-six American Society of Anesthesiologists class I and II patients undergoing an elective posterolateral thoracotomy were randomly divided into 2 groups of 18 each. Before chest closure, an interpleural catheter was inserted under direct vision. At the end of the operation and every 4 hours thereafter, they received either 0.25% bupivacaine with epinephrine or 0.2 mg x kg(-1) morphine sulfate interpleurally for 24 hours. The chest tubes were clamped during injection and for 15 min afterwards. Supplementary doses of intravenous morphine were given on request. The pain severity was evaluated at rest and on coughing before and 30 min after each interpleural injection, using an 11-point visual analog scale. Supplemental analgesic consumption and side effects were recorded. Both interpleural morphine and bupivacaine significantly reduced pain scores 30 min after each injection. However, pain scores and supplementary analgesic requirements were significantly lower in the interpleural morphine group. No serious side effects were detected in either group. Interpleural morphine provides better pain control than interpleural bupivacaine after a posterolateral thoracotomy.

Efficacy of Methods of Intercostal Nerve Blockade for Pain Relief After Thoracotomy

Intercostal nerve blockade for postthoracotomy pain relief can be accomplished by continuous infusion of local anesthetics through a catheter in the subpleural space or through an interpleural catheter, by cryoanalgesia, and by a direct intercostal nerve block. A systematic review of randomized studies indicates that an extrapleural infusion is at least as effective as an epidural and significantly better than narcotics alone. The other techniques of intercostal blockade do not offer an advantage over narcotics alone.

Analgesic effects of interpleural bupivacaine with fentanyl for post-thoracotomy pain

OBJECTIVE

The analgesic effect of bupivacaine/fentanyl with epinephrine given interpleurally after thoracotomy was investigated in a randomized placebo and intravenous controlled study.

DESIGN

Prospective clinical study.

SETTING

University teaching hospital.

PARTICIPANTS

Sixty American Society of Anesthesiologists physical status II and III patients scheduled for posterolateral thoracotomy with general anesthesia.

INTERVENTIONS

Patients were randomly divided into 4 groups to receive either 0.5% bupivacaine/1.5 microg/kg of fentanyl with 5 microg/mL of epinephrine (n = 15, group IPBF), 0.5 % bupivacaine with 5 microg/mL of epinephrine (n = 15, group IPB), or saline (n = 15, group IPS) in a total volume of 15 to 20 mL in 60 seconds by an interpleural catheter placed at the end of surgery by direct vision. The same volume of bupivacaine 0.25% and 1.5 microg/kg of fentanyl with 5 microg/mL of epinephrine to group IPBF, bupivacaine 0.25% with 5 microg/mL of epinephrine to group IPB or saline to group IPS was injected through the interpleural catheter every 6 hours for 48 hours postoperatively. Intravenous fentanyl (n = 15, group IVF) and interpleural saline groups received 1.5 microg/kg of fentanyl intravenously at the first complaint of pain. All patients also received patient-controlled analgesia (PCA) with fentanyl for 48 hours postoperatively. Metamizol sodium was used as a rescue analgesic.

MEASUREMENTS AND MAIN RESULTS

Adequacy of pain relief was evaluated with the "Prince Henry Pain Scale" and visual analog pain scale. Fentanyl consumption via PCA and complications were evaluated for 48 hours. Visual analog scale scores were significantly higher in the interpleural saline group at 4 and 12 hours (6.6 +/- 1.2 and 5.0 +/- 2.1, respectively) postoperatively. Significantly more patients in the IPBF group had lower pain scores during coughing and deep breathing. Fentanyl consumption via PCA device was significantly higher in the intravenous fentanyl group (1,069 +/- 96.9 microg) than the interpleural groups (577.3 +/- 72.2 microg, 651.1 +/- 61.9 microg, and 601.0 +/- 22.6 microg in IPBF, IPB, and IPS groups, respectively).

CONCLUSION

It is concluded that total fentanyl consumption via PCA decreased in all interpleural groups, but pain during coughing and deep breathing was significantly reduced in only the interpleural bupivacaine/fentanyl with epinephrine group.

Postthoracotomy pain management

The following techniques appear efficacious in controlling postthoracotomy pain and reducing the amount of systemic opioids consumed: continuous intercostal blockade, paravertebral blockade, and epidural opioids and/or anesthetics. The combination of thoracic epidural opioid and local anesthetic is very effective at relieving postthoracotomy pain, however, considerable experience is required for insertion of the thoracic epidural catheter and postoperative respiratory monitoring. Intercostal and paravertebral catheters can be inserted intraoperatively under direct visualization, to reduce complications of insertion. One-time intraoperative intercostal blockade may effectively reduce postoperative pain in the first day, but is not a practical long-term method for postthoracotomy pain. The effectiveness of interpleural analgesia, even with proper technique, appears inferior to epidural and other regional techniques. We have incorporated the principles outlined in this review into our general thoracic surgery protocol, as detailed in Fig. 1. Every patient is assessed preoperatively for epidural catheter placement. Contraindications include low platelet count (< 100,000), abnormal coagulation profile, medicinal anticoagulation (aspirin and nonsteroidal anti-inflammatories are not contraindications), bony spinal abnormalities, or neurological disorders. The T5/6 interspace is our preferred level, but T10 can work well with an increased dose of bupivacaine. Upon completion of the muscle sparing, minimal-access thoracotomy, we close the wound and perform a percutaneous intercostal nerve block (two ribs above and three below the incision). We then use patient-controlled epidural analgesia, with a basal infusion of bupivacaine and hydromorphone. To supplement inadequate or nonfunctioning epidurals, intravenous patient-controlled opioids are added. When choosing an approach to postthoracotomy pain management, the thoracic surgeon and anesthesiologist must consider the following: (1) the physician's experience, familiarity and personal complication rate with specific techniques; (2) the desired extent of local and systemic pain control; (3) the presence of contraindications to specific analgesic techniques and medications; and (4) availability of appropriate facilities for patient assessment and monitoring postthoracotomy. Refinements in surgical technique including limited or muscle-sparing thoracotomy, video-assisted thoracoscopic surgery (VATS) and robotic surgery may lessen the magnitude of postthoracotomy pain. We encourage all thoracic surgeons to be knowledgeable of available techniques and maintain a protocol to generate a database for periodic assessment of safety and efficacy.

Regional analgesia in the intensive care unit. Principles and practice

Nociception is a complicated process, and only in recent years have the neural pathways and mediators of pain transmission been unraveled. Several regional anesthetic interventions, most notably epidural drug delivery, can interrupt nociception and provide safe and effective pain control in critically ill patients while substantially reducing the need for systemic medications. This article discusses the possibilities for regional control of the neurobiology of nociception and describes the arsenal of regional anesthetic techniques available to the intensivist. Used wisely, regional techniques can provide excellent pain control and may have a significant role in improving overall patient outcome. Regional analgesia offers the best opportunity to provide substantial analgesia without significant central opioid effects. Well-conducted regional analgesia can reduce many of the unpleasant or potentially problematic side effects observed when traditional intravenous medications are used exclusively for pain control.

Interpleural analgesia does not influence postthoracotomy pain

The management of postthoracotomy pain is a problem and may contribute to atelectasis, leading to hypoxemia, pulmonary infection, and permanent alveolar damage. We sought to determine the efficacy of interpleural analgesia for pain control and to evaluate independent predictors for postoperative pain intensity. Eighty-three patients undergoing elective anterolateral (n = 37) and posterolateral (n = 46) thoracotomy were included in a prospective, randomized, double-blinded trial. Patients were assigned to receive either 0.5% bupivacaine or saline solution interpleurally every 4 h for 10 doses postoperatively. All patients also received patient-controlled analgesics (PCA) with piritramide as the opioid for additional pain control. Pain was assessed on the basis of PCA requirements and by using a visual analog scale. Visual analog scale scores and PCA requirements were not different between groups. Both interpleural bupivacaine and saline significantly reduced pain scores 30 min after the administration. We concluded that pain reduction by interpleural instillation of bupivacaine reflects a placebo-like effect; however, interpleural analgesia is not effective in patients undergoing lateral thoracotomy. Sex and surgical approach were shown to influence postoperative pain intensity at rest, but not during coughing. The female patients, and those undergoing posterolateral thoracotomy, exhibited higher pain scores. This observation appears to be of only marginal clinical significance. The efficacy of interpleural analgesia to reduce postoperative pain intensity in patients after lateral thoracotomy is controversial. In this study we demonstrated a lack of efficacy of interpleural analgesia.

IMPLICATIONS

The efficacy of interpleural analgesia to reduce postoperative pain intensity in patients after lateral thoracotomy is controversial. In this study, we demonstrated a lack of efficacy of interpleural analgesia.

Postthoracotomy Pain Management

In modern medicine, postoperative analgesia is consid ered an integral part of the anesthetic management. Thoracotomy has been reported to be among the most intense clinical postoperative pain experiences. If pain is poorly controlled in the postoperative period, respira tory excursions, movements, and coughing may result in muscle splinting, atelectasis and postoperative pulmo nary dysfunction. This article focuses on the various analgesic modalities that are available for altering the flow of nociceptive information from the periphery to cortex: (1) the transduction of nociceptive information at the peripheral receptor (local anesthetics, nonsteroi dal anti-inflammatory drugs); (2) the transmission of nociceptive information along the afferent sensory neu ral pathways (intercostal, intrapleural, or epidural local anesthetics); and finally, (3) the modulation of nocicep tive input at the level of the dorsal horn of the spinal cord (lumbar or thoracic epidural and intrathecal opi oids) or the brain (systemic opioids). Finally, the role of preemptive analgesia in thoracic surgery is discussed.

The Pharmacology of New Drugs and New Uses for Older Drugs Used for Thoracic Pain Relief

Thoracotomy results in severe pain and deleterious changes in pulmonary physiology. These alterations are inevitable and can be minimized by effective analgesia. There are many options available for the treatment of postthoracotomy pain. Systemic opioids have been extensively used in this context but their side effects have led to the development of various routes of administration; the epidural route in combination with local anesthetics is the most effective. Other techniques include intercostal nerve block and intrapleural analge sia. Drugs such as clonidine, nonsteroidal anti-inflamma tory drugs, and ketamine are promising for the relief of pain after thoracotomy but further investigations are still warranted.

Pleural bupivacaine for pain treatment after nephrectomy

The efficacy of pleural analgesia after nephrectomy is controversial. We therefore evaluated i.v. opioid requirements in patients with and without pleural bupivacaine. Patients undergoing elective nephrectomy were randomly assigned to receive postoperative i.v. piritramid alone (n = 18) or piritramid combined with pleural bupivacaine (n = 19). In the patients assigned to receive pleural analgesia, boluses of 20 mL of 0.25% bupivacaine were given at 6-h intervals via an pleural catheter that was inserted in the medial axillary line at the sixth intercostal space. Pain scores (10-cm visual analog scale) and opioid requirements were recorded over the first 2 postoperative days. One hour after pleural puncture, a chest radiograph was performed. The catheter was removed 48 h after insertion. Patient characteristics were similar in each group, as was the duration of surgery. Pain scores were similar in each group: 3.0 +/- 2.5 in those given pleural bupivacaine and 3.1 +/- 2.7 in those given piritramid alone. However, the piritramid requirement was significantly less in those given pleural bupivacaine (23 +/- 3 mg) than in those given piritramid alone (45 +/- 6 mg). Furthermore, the time from completion of surgery until the first opioid request was significantly longer in the patients who received bupivacaine (4.7 +/- 1.0 vs 2.8 +/- 1.0 h). One patient had a small pneumothorax that resolved without treatment. These data indicate that pleural analgesia is effective and provides a significant opioid-sparing effect.

IMPLICATIONS

We conclude that pleural analgesia significantly prolongs the time until postoperative opioid was first requested and halves the total required dose. These data indicate that pleural analgesia is effective and provides a significant opioid-sparing effect.

Prospective, randomized comparison of extrapleural versus epidural analgesia for postthoracotomy pain

BACKGROUND

Thoracic epidural analgesia is considered the method of choice for postthoracotomy analgesia, but it is not suitable for every patient and is associated with some risks and side effects. We therefore evaluated the effects of an extrapleural intercostal analgesia as an alternative to thoracic epidural analgesia.

METHODS

In a prospective, randomized study, pain control, recovery of ventilatory function, and pulmonary complications were analyzed in patients undergoing elective lobectomy or bilobectomy. Two groups of 15 patients each were compared: one received a continuous extrapleural intercostal nerve blockade (T3 through T6) with bupivacaine through an indwelling catheter, the other was administered a combination of local anesthetics (bupivacaine) and opioid analgesics (fentanyl) through a thoracic epidural catheter.

RESULTS

Both techniques were safe and highly effective in terms of pain relief and recovery of postoperative pulmonary function. However, minor differences were observed that, together with practical benefits, would favor extrapleural intercostal analgesia.

CONCLUSIONS

These results led us to suggest that extrapleural intercostal analgesia might be a valuable alternative to thoracic epidural analgesia for pain control after thoracotomy and should particularly be considered in patients who do not qualify for thoracic epidural analgesia.

Pleural bupivacaine placement for optimal postthoracotomy pulmonary function: a prospective, randomized study

OBJECTIVE

To determine dependent chest tube losses of bupivacaine with paravertebral versus interpleural administration, thereby helping to explain the significant differences in pulmonary function that exist between these two techniques.

DESIGN

A prospective, randomized study.

SETTING

A single hospital.

PARTICIPANTS

Twelve adult patients undergoing posterolateral thoracotomies.

INTERVENTIONS

Paravertebral or interpleural administration of bupivacaine.

MEASUREMENTS AND MAIN RESULTS

Analgesia, as assessed by visual analog pain scores and patient-controlled morphine requirements, was similar in both groups. Postoperative spirometric values were significantly better at most times with the paravertebral route of administration. Dependent chest tube bupivacaine losses were approximately four times higher in the interpleural group.

CONCLUSION

Local anesthetic on the diaphragm might actively impair respiratory function through diaphragmatic and abdominal muscle weakness, while failing to contribute to pain relief.

In vitro controlled release kinetics of local anaesthetics from poly(D,L-lactide) and poly(lactide-co-glycolide) microspheres

Poly(D,L)lactide and polylactide-co-glycolide drug-loaded microspheres were prepared with lipopholic (bupivacaine and etidocaine) and hydrophilic (mepivacine and lidocaine) local anaesthetics. Formulations of drug-loaded microspheres were characterized by the drug content, the in-vitro release kinetics and by the physical state of the drug within the microspheres. Release rates of the local anaesthetics from the microspheres were different and could not be accounted for by the intrinsic dissolution rates of the drugs. The encapsulation efficiency was highly dependent on the lipophilicity of the drugs, reaching the maximum for the lipophilic drugs and the poly(lactide-co-glycolide) polymers. The influence of the molecular weight of the poly(lactide-co-glycolide) polymers on the release rate and on the release mechanism depended on the drug studied and its physical state within the polymeric matrices. Diffusion-controlled release was evidenced in various formulations as a result of the linearity of the release as a function of the square root of time.

Continuous extrapleural intercostal nerve block with continuous infusion of lidocaine after thoracotomy. A descriptive pilot study

Continuous extrapleural intercostal block (EPIB) with bupivacaine has been reported to be an effective analgesic technique in patients after thoracotomy. We report a retrospective study of EPIB using a continuous infusion of 1% lidocaine hydrochloride at a dose of 1 mg/kg/h. A posterior parietal pleural pocket was created and cannulated with a 16-g polyethylene catheter. Lidocaine was perfused over a 3-day period following surgery. Patients also had access to morphine sulfate via patient-controlled analgesia. Eighteen consecutive posterolateral thoracotomies (in 17 patients) performed during a 6-month period were reviewed. Serum lidocaine exceeded the toxic level of 5 microgram/mL in only one patient, a 104.5-kg man who had a level of 5.9 micrograms/mL on postoperative day 2 but experienced no clinical toxicity. Pain was evaluated by verbal analog scores (0 = no pain and 10 = worst pain), which averaged 3.02, 3.14, and 2.8 in the 3 days following surgery. Mean total daily MS doses were 24.3, 37.75, and 34.32 mg (range, 0 to 94 mg). Sedation was scored on a 1 to 5 scale. Mean scores were 2.78, 2.56, and 2.6. No patient died or had a major respiratory complication. Continuous EPIB with lidocaine appears to be a promising adjuvant technique in the management of postthoracotomy pain. Effectiveness needs to be confirmed in a prospective randomized study.

Thoracic paravertebral analgesia

Thoracic paravertebral nerve blockade, although once widely practised, has now only a few centres which contribute to the literature. Data production has, however, continued and this review correlates this new information with existing knowledge. Its history, taxonomy, anatomy, indications, techniques, mechanisms of analgesia, efficacy, contraindications, toxicity, side effects and complications are reviewed. Thoracic paravertebral analgesia is advocated for surgical procedures of the thorax and abdomen, especially wherever the afferent input is predominantly unilateral eg. thoracotomy, cholecystectomy and nephrectomy. It is also of benefit in the prevention and management of chronic pain. It is a simple undertaking with impressive efficacy. Plasma local anaesthetic levels are acceptable and its side effect and complication rates are low. No mortality has been reported. For unilateral surgery of the chest or truck, thoracic paravertebral analgesia should be considered as the afferent block of choice. For bilateral surgery, its efficacy may be limited by the doses of local anaesthetic which could safely be used and further study in this area in particular is required. This form of afferent blockade deserves greater consideration and investigation.

Pain outcomes after thoracotomy: lumbar epidural hydromorphone versus intrapleural bupivacaine

OBJECTIVE

To evaluate postthoractomy analgesia in patients receiving lumbar epidural hydromorphone versus intrapleural bupivacaine.

DESIGN

A randomized, prospective, double-blind study.

SETTING

A university-affiliated medical center.

PARTICIPANTS

Twenty patients undergoing lateral thoracotomy for either pulmonary wedge resection, lobectomy, or pneumonectomy.

INTERVENTION

Nine patients received epidural hydromorphone, and 11 patients received intrapleural bupivacaine in the postoperative period.

MEASUREMENTS AND MAIN RESULTS

Severity of pain was assessed using a visual analog pain scale (VAPS) (0 to 100 mm) at 1, 3, and 5 hours. Patients receiving epidural hydromorphone had a statistically significant improvement in VAPS scores. Patients who received intrapleural bupivacaine did not achieve a significant reduction in pain scores. Nine of 11 patients in the intrapleural bupivacaine group had "failed" postoperative analgesia as defined by a VAPS greater than 30. Only 3 of 9 patients in the continuous epidural hydromorphone group had "failed" analgesia.

CONCLUSION

Epidural hydromorphone is superior to intrapleural bupivacaine in achieving satisfactory pain outcomes during the first 5 hours after thoracotomy.

Spinal controlled delivery of bupivacaine from DL-lactic acid oligomer microspheres

Bupivacaine-loaded microspheres made from DL-polylactic acid oligomers of different molecular weights (MW 2000 and 9000 g/mol, named PLA 2000 and PLA 9000, respectively) which displayed different in vitro release profiles were administered via the spinal route to rabbits. In comparison to the drug administered as a solution (2 mg as equivalent base), PLA 2000 and PLA 9000 microspheres (10 mg as equivalent base) led to a slower uptake of the drug in the systemic circulation, as suggested by the mean maximal plasma concentrations: 326 +/- 81, 321 +/- 57 and 64 +/- 54 ng/mL, respectively. Pharmacodynamic evaluation of the anesthetic action, by means of intensity and time course of motor blockade, indicated a sustained release. In comparison to the drug solution, the PLA 2000 microspheres led to an increase duration of median maximal blockade (172 min versus 44.5 min). The PLA 9000 microspheres failed to reach maximal blockade as a result of a too low release rate.

Interpleural or thoracic epidural analgesia for pain after thoracotomy. A double blind study

The analgetic effect of bupivacaine given epidurally or interpleurally after thoracotomy was investigated in a randomized, double blind, placebo controlled study. 32 patients with both an epidural and an interpleural catheter, were randomized to receive either interpleural or epidural analgesia. The interpleural group was given bupivacaine 5 mg.ml-1 with 5 microgram epinephrine as a 30 ml interpleural bolus, followed by a continuous infusion starting at a rate of 7 ml per hour and epidurally a bolus of 0.9% NaCl followed by a continuous infusion of 0.9% NaCl. The epidural group was given bupivacaine 3.75 mg.ml-1 with 5 microgram epinephrine as a 5 ml epidural bolus, followed by a continuous infusion starting at a rate of 5 ml per hour and interpleurally a bolus of 0.9% NaCl followed by a continuous infusion of 0.9% NaCl. The draining tubes were clamped during the injection of the interpleural bolus and 15 min afterwards. Adequacy of pain relief was evaluated with the Prins-Henry pain scale. Morphine requirement was registered, there was no difference between the groups in pain scores or need for additional morphine.

Lack of efficacy of intrapleural bupivacaine for postoperative analgesia following thoracotomy

Intrapleural bupivacaine has been reported to be effective for analgesia following cholecystectomy and thoracic surgery. Twenty patients who had a posterolateral thoracotomy were studied in a randomized, double-blind, placebo-controlled fashion. Patients were assigned to receive intrapleural administration of either 0.5 percent bupivacaine or saline solution every 4 h for 12 doses postoperatively, as well as narcotic analgesics as needed for additional pain control. Pain was assessed using a visual analogue scale. Narcotic analgesic use, duration of hospitalization, and the development of complications were recorded. There were nine evaluable patients who received bupivacaine, and ten patients who received placebo. The age, sex, and type of operation were similar in the two groups, and the procedures were performed by the same two surgeons. The mean pain score at 24 h postoperatively was 5.8 +/- 0.8 in the bupivacaine group and 6.0 +/- 0.6 in the placebo group. At 48 h, the scores were 4.6 +/- 0.8 in the bupivacaine group and 5.1 +/- 0.9 in the placebo group. The mean dose of morphine sulfate or equianalgesic dose of meperidine during the first 24 h was 13.9 +/- 3.7 mg in the bupivacaine group and 12.6 +/- 1.8 mg in the placebo group, and during the next 24 h it was 40.0 +/- 13.4 mg in the bupivacaine group and 38.0 +/- 9.2 mg in the placebo group. The mean duration of hospitalization was 12.8 +/- 3.2 days in the bupivacaine group and 12.1 +/- 2.9 days in the placebo group. Two patients who received bupivacaine and three patients who received placebo had development of pneumonia or atelectasis postoperatively. There was no statistically significant difference in any parameter between those who received bupivacaine and those who received placebo. Thus, there was no subjective or objective clinical benefit of this method of postoperative analgesia compared with placebo following posterolateral thoracotomy.