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Video-assisted thoracoscopic surgery has become increasingly popular due to faster recovery times and reduced postoperative pain compared with thoracotomy. However, analgesic regimens for video-assisted thoracoscopic surgery vary significantly. The goal of this systematic review was to evaluate the available literature and develop recommendations for optimal pain management after video-assisted thoracoscopic surgery. A systematic review was undertaken using procedure-specific postoperative pain management (PROSPECT) methodology. Randomised controlled trials published in the English language, between January 2010 and January 2021 assessing the effect of analgesic, anaesthetic or surgical interventions were identified. We retrieved 1070 studies of which 69 randomised controlled trials and two reviews met inclusion criteria. We recommend the administration of basic analgesia including paracetamol and non-steroidal anti-inflammatory drugs or cyclo-oxygenase-2-specific inhibitors pre-operatively or intra-operatively and continued postoperatively. Intra-operative intravenous dexmedetomidine infusion may be used, specifically when basic analgesia and regional analgesic techniques could not be given. In addition, a paravertebral block or erector spinae plane block is recommended as a first-choice option. A serratus anterior plane block could also be administered as a second-choice option. Opioids should be reserved as rescue analgesics in the postoperative period. ispartof: ANAESTHESIA vol:77 issue:3 pages:311-325 ispartof: location:England status: published

Item does not contain fulltext Surgery is the primary therapeutic intervention for breast cancer and can result in significant postoperative pain. We searched the current literature and performed a meta-analysis in order to compare the analgesic efficacy of the pectoral type-2 (Pecs II) block with systemic analgesia alone and with a thoracic paravertebral block for breast cancer surgery. Primary outcome was postoperative opioid consumption in the first 24 h after surgery. Secondary outcomes were pain scores at 0, 3, 6, 9 and 24 h after surgery, intra-operative opioid consumption, time to first analgesic request and incidence of postoperative nausea and vomiting. We identified 13 randomised controlled trials that included 815 patients. The Pecs II block significantly reduced postoperative opioid consumption (standardised difference in means: -13.64 mg oral morphine equivalents; 95%CI: -21.22 to -6.05; p < 0.01) and acute postoperative pain at all intervals in the first 24 h after surgery compared with systemic analgesia alone. Compared with the thoracic paravertebral block, the Pecs II block resulted in similar postoperative opioid consumption (standardised difference in means: -8.73 mg oral morphine equivalents; 95%CI: -18.16 to 0.69; p = 0.07) and postoperative pain scores after first measurement. In conclusion, the Pecs II block offers improved analgesic efficacy compared with systemic analgesia alone and comparable analgesic efficacy to a thoracic paravertebral block for breast cancer surgery.

Avoidance of general anaesthesia for breast surgery may be because of clinical reasons or patient choice. There is emerging evidence that the use of regional anaesthesia and the avoidance of volatile anaesthetics and opioid analgesia may have beneficial effects on oncological outcomes. We conducted a prospective observational case series of 16 breast cancer surgeries performed under thoracic paravertebral plus pectoral nerve block with propofol sedation to demonstrate feasibility of technique, patient acceptability and surgeon satisfaction. Fifteen out of 16 cases were successfully completed under sedation and regional anaesthesia, with one conversion to general anaesthesia. Eleven out of 16 cases required low-dose intra-operative opioid analgesia. Out of the 15 surgical procedures completed under regional anaesthesia with sedation, all patients experienced either no or minimal intra-operative pain, and all would choose this anaesthetic technique again. Surgeon-reported operating conditions were 'indistinguishable from general anaesthesia' in most cases, and surgeons were 'extremely satisfied' or 'satisfied' with the technique after every procedure. Combined thoracic paravertebral plus pectoral nerve block with intra-operative sedation is a feasible technique for breast surgery.

Summary The serratus anterior plane block has been described for analgesia of the hemithorax. This study was conducted to determine the spread of injectate and investigate the anatomical basis of the block. Ultrasound-guided serratus anterior plane block was performed on six soft-fix embalmed cadavers. All cadavers received bilateral injections, on one side performed with 20 ml latex and on the other with 20 ml methylene blue. Subsequent dissection explored the extent of spread and nerve involvement. Photographs were taken throughout dissection. The intercostal nerves were involved on three occasions with dye, but not with latex. The lateral cutaneous branches of the intercostal nerve contained dye and latex on all occasions. The serratus plane block appears to be mediated through blockade of the lateral cutaneous branches of the intercostal nerves. Anatomically, serratus plane block does not appear to be equivalent to paravertebral block for rib fracture analgesia.

We examined whether paravertebral block has an effect on the prevalence of persistent postsurgical pain after breast surgery. Seven randomised, controlled trials (559 patients) which had the outcome assessor blinded were included, comparing patients who received paravertebral blocks after breast surgery with patients who did not. The risk ratio (95% CI) was 0.75 (0.48-1.15) for the incidence of postoperative pain at 3 months (four studies, 317 patients); the risk ratio (95% CI) obtained from three studies including 301 patients reporting on pain after 6 months was 0.57 (0.29-1.72), and the risk ratio (95% CI) for pain after 12 months (three trials, 237 patients) was 0.42 (0.15-1.23). Conventional meta-analysis using the random effects model thus showed no statistically significant risk reduction for persistent postoperative pain at 3 months, 6 months or 12 months. Trial sequential analysis, used to consider the risk of type 1 and type 2 random error, showed that at 3 months, 6 months and 12 months, the number of subjects in the analyses were only 18.3%, 6.8% and 4.2% of the required information sizes at those time points, respectively. Our study is the first to evaluate data on pain 12 months postoperatively. Trial sequential analysis revealed that the current evidence is not sufficient to reach a conclusion. These findings stand in contrast to previous meta-analyses with fewer studies that had concluded that paravertebral block effectively reduces chronic pain.

Quadratus lumborum block has recently been described as an effective and long-lasting analgesic strategy for various abdominal operations, including gynaecological laparoscopy. Despite evidence that the analgesic effect is mediated by indirect paravertebral block and that local anaesthetic spreads to the lumbar paravertebral space, there have been no reports to date of lower limb motor weakness. We present a patient with unilateral hip flexion and knee extension weakness leading to unplanned overnight admission following lateral quadratus lumborum block with 20 ml levobupivacaine 0.25%. The L2 dermatomal sensory loss and hip flexion weakness suggested spread to either the L2 paravertebral space or to the lumbar plexus, causing weakness of the psoas and iliacus muscles and possibly the quadriceps. The duration of motor block was approximately 18 h. This complication should be considered when performing the block, especially in the setting of day-case surgery.

It is not known which regional analgesic technique is most effective or safest after open lung resection. We retrospectively examined outcomes in 828 patients who received thoracic epidural analgesia and 791 patients who received paravertebral block after lung resection between 2008 and 2012. We analysed outcomes for 648 patients, 324 who had each analgesic technique, matched by propensity scores generated with peri-operative data. There were 22 out of 324 (7%) postoperative respiratory complications after thoracic epidural and 23 out of 324 (7%) after paravertebral block, p = 0.88. For any postoperative complication, there were 80 out of 324 (25%) and 78 out of 324 (24%) complications, respectively, p = 0.85. There were 17 out of 324 (5%) re-admissions to intensive care after thoracic epidural and 17 out of 324 (5%) after paravertebral block, p > 0.99, and the number of deaths before discharge were 6 out of 324 (2%) and 4 out of 324 (1%), respectively, p = 0.53. There was no significant difference in median (IQR [range]) hospital stay after thoracic epidural or paravertebral block, 6 (5-9 [2-94]) days vs. 6 (5-9 [2-122]), respectively, p = 0.83. Our study suggests that rates of complications as well as length of hospital stay after thoracic epidural analgesia and paravertebral blockade are similar. We were unable to compare analgesic efficacy due to incomplete data.

Current descriptions of thoracic paravertebral block techniques require the needle tip to be anterior to the superior costotransverse ligament. We hypothesised that an injection point midway between the posterior border of the transverse process and the pleura would result in spread to the paravertebral space. We completed bilateral injections of 5 ml methylene blue 0.2% midway between the posterior border of the transverse process and the pleura at T2, T4, T6, T8 and T10 in three unembalmed cadavers. The presence of methylene blue dye at the nerve root in the paravertebral space, the corresponding intercostal nerve and sympathetic chain at the level of injection, and at additional levels, was examined. We identified the superior costotransverse ligament, pleural displacement and spread to the erector spinae plane. We describe two case reports using this technique in patients. Our cadaver results and clinical cases demonstrate that, with the exception of cadaver 1, an injection point midway between the posterior border of the transverse process and pleura consistently achieved spread of dye at least to the paravertebral space at the level of injection, and frequently to adjacent levels. This may be a plausible explanation for the landmark technique's inability to reliably achieve a multilevel block. We describe a new ultrasound-guided technique for a single level paravertebral block.

Factors affecting the distribution of continuous thoracic paravertebral block have never been examined. We designed this prospective, double-blind study to check whether continuous thoracic paravertebral block with a higher ropivacaine concentration would provide a wider segmental sensory block spread. Sixty consecutive patients undergoing pulmonary lobectomy or segmentectomy were randomly allocated to receive continuous paravertebral infusion of either 0.2% or 0.5% ropivacaine (6 ml.h(-1) ). The primary outcome was the number of anaesthetised dermatomes as determined by loss of cold sensation 24 h after surgery. Twenty-seven patients per group were included in the final analysis. The median (IQR [range]) number of anaesthetised dermatomes 24 h after surgery was 4 (3-6 [1-9]) with ropivacaine 0.2% and 4 (3-6 [2-11]) with ropivacaine 0.5% (p = 0.66). Contrary to our expectation, the segmental spread of sensory block produced by continuous thoracic paravertebral block does not depend on ropivacaine concentration.

The aim of this prospective clinical study was to evaluate the location of paravertebral catheters that were placed using the classical landmark puncture technique and to correlate the distribution of contrast dye injected through the catheters with the extent of somatic block. Paravertebral catheter placement was attempted in 31 patients after video-assisted thoracic surgery. In one patient, an ultrasound-guided approach was chosen after failed catheter placement using the landmark method. A fluoroscopic examination in two planes using contrast dye was followed by injection of local anaesthetic and subsequent clinical testing of the extent of the anaesthetised area. In nine patients (29%), spread of contrast dye was not seen within the paravertebral space as intended. Misplaced catheters were in the epidural space (three patients), in the erector spinae musculature (five patients), and in the pleural space (one patient). There was also a discrepancy between the radiological findings and the observed distribution of loss of sensation. We have demonstrated an unacceptably high misplacement rate of paravertebral catheters using the landmark method. Additional research is required to compare the efficacy and safety of continuous paravertebral block using ultrasound-guided techniques or surgical inserted catheters.

There are conflicting results with regard to the use of catheter-based techniques for continuous paravertebral block. Local anaesthetic spread within the paravertebral space is limited and the clinical effect is often variable. Discrepancies between needle tip position and final catheter position can also be problematic. The aim of this proof-of-concept study was to assess the reliability of placing a newly developed coiled catheter in human cadavers. Sixty Tuohy needles and coiled catheters were placed under ultrasound guidance, three on each side of the thoracic vertebral column in 10 human cadavers. Computed tomography was used to assess needle tip and catheter tip locations. No catheter was misplaced into the epidural, pleural or prevertebral spaces. The mean (SD) distance between catheter tips and needle tips was 8.2 (4.9) mm. The median (IQR [range]) caudo-cephalad spread of contrast dye injectate through a subset of 20 catheters was 4 (4-5[3-8]) thoracic segments. All catheters were removed without incident. Precise paravertebral catheter placement can be achieved using ultrasound-guided placement of a coiled catheter.

Thoracic paravertebral blockade has been described as an effective alternative to epidural blockade for the management of postoperative pain after thoracic surgery. Here we present what we believe is the first description of the use of thoracic paravertebral block as the sole anaesthetic for video-assisted thoracoscopy. Two oncology patients with severe respiratory disease presented for video-assisted thoracoscopic surgery. Thoracic paravertebral block provided excellent surgical conditions and postoperative pain relief for these patients and allowed an optimal assessment of the anaesthetic impact on respiratory function.

P>In this review, we discuss the central non-neuraxial regional anaesthesia blocks of the abdomen, including intercostal and intrapleural blocks, rectus sheath and ilioinguinal-iliohypogastric blocks, transversus abdominis plane blocks and paravertebral blocks.

Summary The aim of this study was to compare the efficacy of nerve stimulator guided paravertebral block with ilio-inguinal nerve block in children undergoing inguinal herniorrhaphy. Eighty children were randomly allocated to receive either paravertebral block or ilio-inguinal nerve block. Each block was evaluated in terms of intra-operative haemodynamic stability, postoperative pain scores at rest, on movement and during activity, requirement for supplemental analgesia and parental satisfaction. Haemodynamic stability was maintained significantly better during sac traction in the paravertebral block group (p < 0.005). Pain scores and analgesic consumption were significantly lower in the paravertebral block group during the postoperative follow-up period (p < 0.05). Parental satisfaction (93% vs 69%) and surgeon satisfaction (93% vs 64%) were significantly higher in the paravertebral block group (p < 0.05). Paravertebral blockade improved and prolonged postoperative analgesia, and was associated with greater parental and surgeon satisfaction when compared to ilio-inguinal nerve block.

Plasma concentrations of lignocaine were determined in six ASA 1 children treated with thoracic paravertebral blockade. Peak concentrations ranged between 1.7 and 3.0 micrograms.ml-1 after a bolus injection of lignocaine 0.5 ml.kg-1 (lignocaine 10 mg.ml-1 with adrenaline 5 micrograms.ml-1) and peak plasma concentrations were reached 15-30 min after injection. Two hours after the initial bolus a continuous infusion of the same lignocaine solution was started (0.25 ml.kg-1.h-1). Steady state levels of lignocaine were reached 8-10 h after the start of the infusion and ranged from 2.1-3.2 micrograms.ml-1. This regimen for paravertebral block in children resulted in moderate plasma concentrations of lignocaine, well below those which might result in side effects or systemic toxicity.

Summary Paravertebral analgesia is highly effective in blocking unilateral afferent input from the trunk, but its bilateral use does not appear to have been described. Eight patients undergoing major abdominal vascular surgery had pre-operative bilateral paravertebral catheters inserted. A dose of 25 ml of bupivacaine 0.5% divided between the two catheters provided the basis of an effective intra-operative analgesic regimen which was continued postoperatively by infusion of bupivacaine for 4 days. Diclofenac and morphine completed a balanced analgesic regimen which was started pre-operatively and continued for 5 and 3 days respectively. Cardiovascular stability was notable throughout surgery, even with aortic clamping and all patients were extubated at the end of surgery. Good quality analgesia was obtained as assessed by low postoperative pain scores at rest and on movement. Three patients were not admitted to the intensive care unit, where mean stays for the group was 10 h (range 0-24 h) and mean hospital stay was 10 days (range 7–14). There were no additional demands made on the nursing staff and no postoperative pain-related complications occurred. We conclude that bilateral paravertebral analgesia, as part of a balanced analgesic technique, is an alternative method of providing effective afferent blockage for major abdominal surgery.

Six patients undergoing paravertebral blocks for chronically painful conditions of the chest wall were thermographically imaged so that the extent of cutaneous vasodilatation and hence sympathetic block could be correlated with the distribution of the somatic block. All blocks were performed by a single experienced operator, with a single percutaneous entry, using 15 ml of 0.5% bupivacaine at a mean level of T9-10 (range T7-8--T10-11), with radiological confirmation of correct needle placement. There was a mean distribution of the somatic block of five dermatomes (range 1-8), as evidenced by loss of pinprick sensation, with upper and lower limits of T6 and L3. The mean distribution of the sympathetic block was eight dermatomes (range 6-10), as evidenced by ipsilateral skin warming (p = 0.0005-0.001), with upper and lower limits of T5 and L3. No bilateral spread was observed. No significant postural changes in blood pressures were seen, although there was a small but significant decrease in supine heart rate (p = 0.05). This study demonstrates that a large unilateral somatic and sympathetic block is obtainable with a single thoracic percutaneous paravertebral injection. It challenges the suggestions that this method of analgesia is ineffective and hazardous, that a sympathetic component is a rare accompaniment and that the lumbar nerve roots are spared.

The major drawback of paravertebral space location using the traditional method of loss of resistance to air or saline is a failure rate of at least 10%. We investigated whether pressure measurement during needle advancement could improve reliability. Twenty-nine blocks in 14 awake adult patients undergoing treatment for chronically painful neuralgic conditions of the chest or abdominal wall were studied. In erector spinae, the mean inspiratory pressure (29.5 mmHg, SD 14.2), exceeded the expiratory pressure (19.4 mmHg, SD 9.7). However, upon traversing the superior costo-transverse ligament, there was a sudden lowering of pressures and the mean expiratory pressure (7.6 mmHg, SD 3.7) exceeded the inspiratory pressure (3.3 mmHg, SD 2.9). No negative pressures were recorded. Correct needle placement was confirmed by X ray screening and contrast injection. All blocks were successful and uncomplicated. Location of the paravertebral space by this objective method of 'pressure inversion' improves sensitivity and specificity and should lead to an improvement in the success rate of thoracic paravertebral analgesia.

The failure rate and complications were studied prospectively in 367 paediatric and adult patients who had received a thoracic or lumbar paravertebral block. The overall failure rate was 10.1%; adults 10.7%; children 6.2%. The frequency of complications were: hypotension: 4.6%; vascular puncture: 3.8%; pleural puncture: 1.1%; pneumothorax: 0.5%. Since these results are similar to those found with alternative methods, e.g. epidural, intrapleural and intercostal blocks, paravertebral block can be recommended as an effective, safe technique for unilateral analgesia in both adults and children.

The failure rate and complications following thoracic and lumbar paravertebral blocks performed in 620 adults and 42 children were recorded. The technique failure rate in adults was 6.1%. No failures occurred in children. The complications recorded were: inadvertent vascular puncture (6.8%); hypotension (4.0%); haematoma (2.4%); pain at site of skin puncture (1.3%); signs of epidural or intrathecal spread (1.0%); pleural puncture (0.8%); pneumothorax (0.5%). No complications were noted in the children. The use of a bilateral paravertebral technique was found approximately to double the likelihood of inadvertent vascular puncture (9% vs. 5%) and to cause an eight-fold increase in pleural puncture and pneumothorax (3% vs. 0.4%), when compared with unilateral blocks. The incidence of other complications was similar between bilateral and unilateral blocks.

Summary The caudal limit of the thoracic paravertebral space was examined in 13 human cadavers. The origin of the psoas major muscle was found to completely seal off the paravertebral space below the level of the 12th thoracic vertebra. The possibility of caudal spread of a thoracic paravertebral block below this level through the paravertebral space would appear unlikely.

Continuous paravertebral block has not previously been described for use in children. This study reports the use of this technique in five patients (aged 7 months to 8 years) scheduled for renal surgery or cholecystectomy. The block was not difficult to perform and provided good intra- and postoperative analgesia. Continuous paravertebral block appears to be a promising technique for pain management in children and might prove a valuable addition in the field of paediatric regional anaesthesia.

Summary Patients were admitted as day-cases for inguinal herniorrhaphy under epidural anaesthesia and chlormethiazole sedation. The patients were given oral analgesia, and in addition, some were given either a paravertebral block with a dextran/bupivacaine mixture or cryoanalgesia of the ilio-inguinal nerve for postoperative pain relief. These anaesthetic and analgesic techniques are discussed in relation to day-case herniorrhaphy.

An accurate, simple and safe method, based upon cadaver studies, of obtaining a thoracic paravertebral block, suitable for repeated administration by catheter or for permanent accurate neurolytic block, and which carries significant advantages over intercostal or epidural block, is described in theory and practice.

Summary The case is reported of a patient who received an accidental intrathecal injection of a mixture containing 0.375% plain bupivacaine in dextran following a paravertebral block. From the duration of anaesthesia produced, it is suggested that the addition of dextran to a solution of bupivacaine does not potentiate the action of subarachnoid bupivacaine.