Psoas Compartment Block Research Articles

Combined Psoas Compartment Block and Sciatic Nerve Block for Elective Lower Limb Surgeries

AIM AND OBJECTIVE OF THE STUDY : This study was aimed at evaluation of the motor and sensory blockade and post operative analgesia using both psoas compartment block and sciatic nerve block in elective lower extremity surgeries. PRIMARY OBJECTIVE : To assess the effectiveness of the lower limb block based on 1. Sensory block. 2. Motor block. 3. Post operative analgesia. SECONDARY OBJECTIVE : To assess the onset of block, total duration of block, and the time taken for the first dose of rescue analgesia and to look for complications if any MATERIAL AND METHOD : DESIGN OF THE STUDY: Randomized Prospective study. Selection of Subjects : • Study involves adult patients between 18 to 60 years ofASAps I- II posted for elective lower limb surgeries. • Sample size 60. • Randomization – computer generated random numbers. PSOAS COMPARTMENT BLOCK AND SCIATIC NERVE BLOCK : Sixty patients subjected to psoas compartment block followed by sciatic nerve block using nerve stimulator 0.25% bupivacaine over 30 ml for psoas compartment block and 0.25% of 20ml bupivacaine for sciatic nerve block was administered. Under strict aseptic precautions, psoas compartment block performed by winnes technique and and sciatic nerve block by labat’s technique using peripheral nerve stimulator after obtaining twitch of quadriceps and calf muscle contraction and dorsiflexion of foot. Results are based on following parameters. • Time of onset of sensory blockade. • Time taken for onset of motor blockade. • From the time of block, visual analogue scale noted for every 30 minutes 1hour, 2 hour by 4, 6, and 8 hours • From the time of block Bromage score noted for 2, 6,and 8 hours. • Time elapsed till first rescue analgesia dose. • The incidence of first dose of rescue analgesia at 9 to 10 hours is 48.3 % (29 out of 60 patients) and at 10 to 11 hours is 51.7 % (31 out of 60 patients). • Sensory blockade by visual analogue scale reveals no pain upto 8 hours and almost complete block upto 6 hours in 73.3% of patients and good analgesic effect upto 9 to 10 hours in 48.3 % (29 out of 60 patients) and at 10 to 11 hours is 51.7 % (31 out of 60 patients). • So overall combined psoas comapartment block and sciatic nerve block provides effective sensoryblockade, motor blockade and good postoperative analgesic effect. CONCLUSION : This study concluded that skillful application of psoas compartment block by posterior approach [WINNIES APPROACH] and proximal sciatic nerve blockv [LABATS APPROACH] provides adequate intraoperative analgesia for major lower extremity procedures and maintains prolonged postoperative analgesia with significantly lower consumption of opioid analgesics. It also provides, early ambulation, short hospital stay and far less side effects when compared with neuroaxial blocks such as hemodynamic instability, meningeal irritation, introduction of infections, neurological complications and others. Finally, both patient and surgeon satisfaction were achieved successfully with psoas compartment block and sciatic nerve block. Combined psoas compartment block and sciatic nerve block is a safe and effective alternative for analgesia for lower limb surgeries.

Advances in preclinical human immune response studies – redefining immunogenicity

Modern joint arthroplasty protocols place an emphasis on minimizing patient-reported postoperative pain while minimizing opioid consumption. The use of multimodal pain management protocols has been reported to improve patient outcomes and satisfaction after total hip arthroplasty.In a prospective, single-surgeon trial, 50 patients undergoing primary direct anterior approach total hip arthroplasty were randomized to receive a preoperative fascia iliaca compartment block (FICB) or an intraoperative surgeon-delivered psoas compartment block (PCB). Patient-reported pain was recorded in the postanesthesia care unit, recovery floor and 3 weeks postoperatively. Opioid use was recorded during the hospital stay.Average visual analog scale pain scores in the postanesthesia care unit were 38.7 ± 8.7 vs 35.6 ± 8.3 (P = .502) for the preoperative FICB and intraoperative PCB groups, respectively. No significant difference was found between groups at the 3-week visit for postoperative pain (FICB: 2.9 ± 1.4; PCB: 3.2 ± 2.0; P = .970) and patient-reported pain satisfaction (FICB: 8.8 ± 2.2; PCB: 9.7 ± 0.6; P = .110).During the direct anterior approach for total hip arthroplasty, PCB is an effective and efficient regional anesthesia technique. It may be used to obtain satisfactory postoperative pain control and patient satisfaction while decreasing hospital resources.

Psoas Compartment Block vs Periarticular Local Anesthetic Infiltration for Pain Management After Anterior Total Hip Arthroplasty: A Prospective, Randomized Study

BackgroundThe psoas compartment block (PCB) or periarticular soft-tissue local anesthetic injection are forms of regional anesthesia often used as one of the components in multimodal anesthesia applied during total hip arthroplasty (THA). The most efficacious form of regional anesthesia for THA has yet to be determined. MethodsIn a single-surgeon, prospective, clinical trial, patients undergoing THA via direct anterior approach were randomized to receive an intraoperative periarticular local anesthetic infiltration (periarticular injection) or a PCB. Postoperative pain scores, narcotic consumption, and complications were recorded. ResultsForty-nine patients were randomized to the PCB and 50 were randomized to the periarticular injection. The resting pain score 3 hours postoperatively was statistically significantly lower in the periarticular injection group by 1.1 point (2.9 ± 2.2 vs 4.0 ± 2.2, P = .036). No difference was found in resting pain scores or ambulatory pain scores in the morning or evening of postoperative day 1, 2, or at the 3-week follow-up visit. There was no difference in in-hospital narcotic consumption between groups (P = 1.0). There were no major complications directly related to the block in either group. A total of 6 patients reported complaints of transient numbness, 5 in the PCB group (5/49, 10.2%), and one in the periarticular injection group (1/50, 2%, P = .087). ConclusionThese results demonstrate similarity between the 2 methods. We prefer periarticular anesthetic infiltration over PCB due to improved immediate postoperative pain scores and avoidance of potential symptoms associated with nerve blockade.

Late Retroperitoneal Haematoma after Psoas Compartment Block for Total Hip Arthroplasty

Late Retroperitoneal Haematoma after Psoas Compartment Block for Total Hip Arthroplasty

Intraoperative Psoas Compartment Block vs Preoperative Fascia Iliaca Block for Pain Control After Direct Anterior Total Hip Arthroplasty: A Randomized Controlled Trial

BackgroundModern joint arthroplasty protocols place an emphasis on minimizing patient-reported postoperative pain while minimizing opioid consumption. The use of multimodal pain management protocols has been reported to improve patient outcomes and satisfaction after total hip arthroplasty. MethodsIn a prospective, single-surgeon trial, 50 patients undergoing primary direct anterior approach total hip arthroplasty were randomized to receive a preoperative fascia iliaca compartment block (FICB) or an intraoperative surgeon-delivered psoas compartment block (PCB). Patient-reported pain was recorded in the postanesthesia care unit, recovery floor and 3 weeks postoperatively. Opioid use was recorded during the hospital stay. ResultsAverage visual analog scale pain scores in the postanesthesia care unit were 38.7 ± 8.7 vs 35.6 ± 8.3 (P = .502) for the preoperative FICB and intraoperative PCB groups, respectively. No significant difference was found between groups at the 3-week visit for postoperative pain (FICB: 2.9 ± 1.4; PCB: 3.2 ± 2.0; P = .970) and patient-reported pain satisfaction (FICB: 8.8 ± 2.2; PCB: 9.7 ± 0.6; P = .110). ConclusionDuring the direct anterior approach for total hip arthroplasty, PCB is an effective and efficient regional anesthesia technique. It may be used to obtain satisfactory postoperative pain control and patient satisfaction while decreasing hospital resources.

Comparison of psoas compartment block and epidural block for postoperative analgesia in hip surgeries

Context: Psoas compartment block via lumbar paravertebral approach has been compared with epidural block for postoperative pain relief following hip surgery. Settings and Design: This prospective, randomized study was conducted in the department of Anesthesia in a tertiary care hospital. Materials and Methods: This study was conducted on 60 patients undergoing unilateral hip surgery. They were randomly assigned to either psoas compartment (P) or epidural (E) group (30 in each group). A lumbar paravertebral (psoas compartment) or epidural catheter was placed before the start of surgery. A subarachnoid block using 0.5% hyperbaric bupivacaine and fentanyl was subsequently administered. After 2 h, a loading dose of 10 ml of 0.25% bupivacaine was given, and infusion of the same drug started at 5 ml/h in group P and 5 ml/h of 0.125% bupivacaine in group E using an elastomeric infusion pump. The patients were observed for 24 h and quality of pain relief with both the techniques was compared. Statistical Analysis: Categorical variables were analyzed with Chi-square test while continuous variables were analyzed with Student's t-test. Visual analog scale was expressed as median and was analyzed with Mann–Whitney test. A software program (SPSS 21) was used. P 0.05), which was not statistically significant. Mean pain scores at 4 and 8 h postoperatively were higher in the psoas compartment block resulting in greater rescue analgesic requirement in this group. Conclusions: Psoas compartment block can be considered an alternative in patients with relative contraindications to epidural block such as those on deep vein thrombosis prophylaxis with anticoagulants.

Psoas compartment block for intraoperative anesthesia for fracture neck of femur: Case report.

Psoas compartment block for intraoperative anesthesia for fracture neck of femur: Case report.

Intravenous dexamethasone fails to prolong psoas compartment block when assessed by objective pinprick sensory testing: a prospective, randomised, dose-dependent, placebo-controlled equivalency trial

BackgroundRecent studies have concluded that i.v. dexamethasone can prolong the duration of peripheral nerve blockade. We hypothesized that a 4 mg dose would equally prolong the duration of psoas compartment blocks (PCBs) when compared with 8 mg, and that both doses would prolong the duration when compared with placebo. MethodsThis was a prospective, randomized, placebo-controlled, dose-dependent, equivalency trial with 115 patients undergoing total hip arthroplasty. The patients received a PCB. Subsequently, 15 patients received i.v. normal saline (placebo), 50 patients received i.v. dexamethasone 4 mg, and 50 patients received i.v. dexamethasone 8 mg. The primary outcome was the duration in hours of PCB, determined by serial pinprick assessments. Secondary outcomes included pain scores, time to first analgesic, and opioid consumption. An intention-to-treat-analysis (ITA) and per-protocol analysis (PPA) were performed. ResultsThe ITA showed that block duration in the 4 and 8 mg groups was equivalent [mean (standard deviation), 18.5 h (8.0) vs 18.1 h (7.1)]. However, neither group differed from placebo [19.6 h (6.7), (4 mg vs placebo), P=0.97; (8 mg vs placebo), P=0.77)]. Postoperative pain scores and opioid consumption were not different between groups. Time to first analgesic was not different between the 4 and 8 mg groups, or the 4 mg and placebo groups. The 8 mg group, however, had a longer time to first analgesic (median of 533 vs 432 min, P=0.047) when compared with placebo, although the significance was not observed in the PPA (P=0.058). ConclusionsI.V. dexamethasone did not prolong PCB when duration was objectively assessed, or decrease total opioid consumption. However, dexamethasone 8 mg prolonged the time to first analgesic. Clinical trial registrationNCT 02464176.

Peripheral Nerve Blocks for the Lower Extremity

Lower extremity peripheral nerve blocks (PNBs) are often used for surgical anesthesia and postoperative pain management. The use of PNB provides improved analgesia, reduced opioid consumption, and improved patient satisfaction and can facilitate earlier rehabilitation and discharge. As the number of lower extremity total joint arthroplasties is projected to increase significantly, the role of peripheral nerve blocks can be expected to grow in similar fashion. With the growing number of procedures and the increasing focus on patient experience and expeditious hospital discharge, PNBs are increasingly recognized as a powerful tool to improve patient care and facilitate recovery after lower extremity surgery. We provide a basic review of regional anesthesia for lower extremity surgical procedures. The widespread availability of ultrasonography has improved the performance and efficacy of PNBs; thus, we focus on ultrasonography-guided procedures. In this review, we discuss pertinent lower extremity anatomy and sonoanatomy, indications, patient outcome measures, techniques, and complications of the most commonly used blocks. This review contains 35 figures, 11 tables, 5 videos, and 103 references. Key words: adductor canal block, analgesia, ankle block, clinical applications of peripheral nerve blocks, complications of peripheral nerve blocks, continuous peripheral nerve catheter, early ambulation, fascia iliaca compartment block, femoral nerve block, lower extremity nerve blocks, lower extremity regional anesthesia, lumbar plexus block, obturator nerve block, peripheral nerve block, peripheral nerve catheter, popliteal block, psoas compartment block, regional anesthesia, regional anesthesia techniques, saphenous nerve block, sciatic nerve block, ultrasonography guided

Peripheral Nerve Blocks for the Lower Extremity

Lower extremity peripheral nerve blocks (PNBs) are often used for surgical anesthesia and postoperative pain management. The use of PNB provides improved analgesia, reduced opioid consumption, and improved patient satisfaction and can facilitate earlier rehabilitation and discharge. As the number of lower extremity total joint arthroplasties is projected to increase significantly, the role of peripheral nerve blocks can be expected to grow in similar fashion. With the growing number of procedures and the increasing focus on patient experience and expeditious hospital discharge, PNBs are increasingly recognized as a powerful tool to improve patient care and facilitate recovery after lower extremity surgery. We provide a basic review of regional anesthesia for lower extremity surgical procedures. The widespread availability of ultrasonography has improved the performance and efficacy of PNBs; thus, we focus on ultrasonography-guided procedures. In this review, we discuss pertinent lower extremity anatomy and sonoanatomy, indications, patient outcome measures, techniques, and complications of the most commonly used blocks. This review contains 35 figures, 11 tables, 5 videos, and 103 references. Key words: adductor canal block, analgesia, ankle block, clinical applications of peripheral nerve blocks, complications of peripheral nerve blocks, continuous peripheral nerve catheter, early ambulation, fascia iliaca compartment block, femoral nerve block, lower extremity nerve blocks, lower extremity regional anesthesia, lumbar plexus block, obturator nerve block, peripheral nerve block, peripheral nerve catheter, popliteal block, psoas compartment block, regional anesthesia, regional anesthesia techniques, saphenous nerve block, sciatic nerve block, ultrasonography guided

Comparison of Spinal Nerve Root Block Alone and Spinal Nerve Root Block with Psoas Compartment Block in Patients with a Herniated Lumbar Disc

Comparison of Spinal Nerve Root Block Alone and Spinal Nerve Root Block with Psoas Compartment Block in Patients with a Herniated Lumbar Disc

Psoas compartment and sacral plexus block via electrostimulation for pelvic limb amputation in dogs

ObjectiveTo assess the efficacy of psoas compartment and sacral plexus block for pelvic limb amputation in dogs. Study designProspective clinical study. AnimalsA total of 16 dogs aged 8±3 years and weighing 35±14 kg (mean±standard deviation). MethodsDogs were administered morphine (0.5 mg kg−1) and atropine (0.02 mg kg−1); anesthesia was induced with propofol and maintained with isoflurane. Regional blocks were performed before surgery in eight dogs with bupivacaine (2.2 mg kg−1) and eight dogs were administered an equivalent volume of saline. The lumbar plexus within the psoas compartment was identified using electrolocation lateral to the lumbar vertebrae at the fourth–fifth, fifth–sixth and sixth–seventh vertebral interspaces. The sacral plexus, ventrolateral to the sacrum, was identified using electrolocation. Anesthesia was monitored using heart rate (HR), invasive blood pressure, electrocardiography, expired gases, respiratory frequency and esophageal temperature by an investigator unaware of the group allocation. Pelvic limb amputation by coxofemoral disarticulation was performed. Dogs that responded to surgical stimulation (>10% increase in HR or arterial pressure) were administered fentanyl (2 μg kg−1) intravenously for rescue analgesia. Postoperative pain was assessed at extubation; 30, 60 and 120 minutes; and the morning after surgery using a visual analog scale (VAS). ResultsThe number of intraoperative fentanyl doses was fewer in the bupivacaine group (2.7±1.1 versus 6.0±2.2; p<0.01). Differences in physiologic variables were not clinically significant. VAS scores were lower in bupivacaine dogs at extubation (0.8±1.9 versus 3.8±2.5) and at 30 minutes (1.0±1.4 versus 4.3±2.1; p<0.05). Conclusions and clinical relevancePsoas compartment (lumbar plexus) and sacral plexus block provided analgesia during pelvic limb amputation in dogs.

The Effect of Unilateral Spinal Anaesthesia and Psoas Compartment with Sciatic Block on the Postoperative Pain Management in Total Knee Artroplastic Surgery.

Purpose. This study was designed to investigate the effects of peripheral nerve block methods, applied through unilateral spinal anaesthesia on elderly patients to undergo total knee arthroplasty, on perioperative hemodynamic parameters and postoperative analgesia period. Materials and Method. 60 patients were randomly divided into two groups in the study. In group USA spinal anaesthesia was performed. In group PCS it was applied on psoas compartment block and sciatic nerve block. Results. Significantly higher intraoperative 60th and 90th minute mean arterial pressure values were ascertained in the PCS group compared to the USA group. The decrease observed in the 5th, 10th, and 20th minute MAP values in the USA group was statistically significant according to the control MAP value. Concerning within group comparisons, the decrease in 5th, 10th, and 20th minute heart rate values in the USA group was statistically significant compared with the control measurement value. The mean beginning time of sensory and motor blocks in the PCS group was found to be at a significantly advanced level compared with that in the USA group. Conclusions. The PCS block technique using bupivacaine hydrochloride ensured a higher haemodynamic efficiency in the perioperative period in high-risk elderly patients undergoing total knee arthroplasty. This trial is registered with ClinicalTrials.gov Identifier: NCT03021421.

The comparative study of two techniques of lumbar plexus block by anterior and posterior approach for lower limb surgery

Background: Lower extremity peripheral nerve blocks (PNBs) have been traditionally less employed compared to other forms of regional anesthesia. The advent of peripheral nerve stimulator and ultrasonography, complications associated with neuraxial anesthesia, and improved rehabilitation with PNBs has led to renewed interest in lower limb blocks. Lumbar plexus block can be given by anterior (Winnie's “3 in 1” block) and posterior (psoas compartment block) approaches. Subjects and Methods: In this randomized, observer-blinded study, we compared these techniques in two groups of patients (Group A [n = 30] and Group P [n = 30]) undergoing lower limb surgeries using nerve locator. They were supplemented with sciatic nerve block by Labat's approach. The primary objective was to compare the onset of sensory and motor blockade. Secondary objectives included the duration of sensory and motor blockade, sparing of nerves and complications if any. The onset of sensory analgesia was assessed by visual analog scale

Study on evaluating the Adequacy of Psoas Compartment Block and Sacral Plexus Block for Lower Limb Surgeries

Study on evaluating the Adequacy of Psoas Compartment Block and Sacral Plexus Block for Lower Limb Surgeries

An Evaluation of Ultrasound-Guided Adductor Canal Blockade for Postoperative Analgesia After Medial Unicondylar Knee Arthroplasty

Unicondylar knee arthroplasty (UKA) is a commonly performed procedure with significant expected postoperative pain. Peripheral nerve blocks are 1 analgesic option, but some approaches may decrease quadriceps motor strength and interfere with early ambulation. In this study, we compared the analgesia provided by an adductor canal block (ACB) and a psoas compartment block (PCB) after UKA. We hypothesized that the ACB would provide equivalent analgesia, defined as a difference of <2 points on the pain scale (0-10 numeric rating scale [NRS]), at rest and with movement 6 hours after block placement. One hundred fifty patients undergoing medial UKA were randomly assigned to receive either an ACB or a PCB with 0.25% bupivacaine, 5 μg/mL epinephrine, and 1.67 μg/mL clonidine. All patients received multimodal analgesics, sham blockade at the alternate site, and a posterior capsule injection during surgery. Patients and observers were blinded to treatment groups. The primary end points were NRS pain scores with rest and movement at 6 hours. Secondary end points included quadriceps muscle strength at 6 hours (0-5 [5 being full strength]; Medical Research Council scale) as well as NRS pain scores, opioid consumption, and opioid-related side effects over 24 hours. One hundred forty-seven patients were analyzed. Pain scores were equivalent at 6 hours with rest (ACB 1.0 ± 2 vs PCB 1.1 ± 2.2 [mean NRS ± SD]; 95% confidence interval of mean difference, -0.8 to 0.6; P < 0.0001) and with movement (ACB 1.6 ± 2.6 vs PCB 1.5 ± 2.8; 95% confidence interval of mean difference, -0.8 to 0.9; P < 0.0001). In addition, pain scores at rest and with movement at 12, 18, and 24 hours were equivalent. Quadriceps motor strength was significantly increased in the ACB group (Medical Research Council scale score, 4.0 ± 1.1 vs 2.5 ± 1.3 [mean ± SD]; P < 0.0001). No significant differences were found between groups for time to first analgesic or for cumulative opioid consumption at 6, 12, 18, or 24 hours. Other than an increase in the incidence of pruritus in the ACB group at 6 hours, there were no differences in opioid-related side effects. An ACB provides equivalent analgesia after medial UKA when compared with a PCB. In addition, the ACB caused significantly less motor weakness. An ACB should be considered for postoperative analgesia after medial UKA.

Real-time ultrasound-guided comparison of adductor canal block and psoas compartment block combined with sciatic nerve block in laparoscopic knee surgeries.

Background:Lumbar plexus block, combined with a sciatic nerve block, is an effective locoregional anesthetic technique for analgesia and anesthesia of the lower extremity. The aim of this study was to compare the clinical results outcome of the adductor canal block versus the psoas compartment block combined with sciatic nerve block using real time ultrasound guidance in patients undergoing elective laparoscopic knee surgeries.Patients and Methods:Ninety patients who were undergoing elective laparoscopic knee surgeries were randomly allocated to receive a sciatic nerve block in addition to lumbar plexus block using either an adductor canal block (ACB) or a posterior psoas compartment approach (PCB) using 25 ml of bupivacine 0.5% with adrenaline 1:400,000 injection over 2-3 minutes while observing the distribution of the local anesthetic in real time. Successful nerve block was defined as a complete loss of pinprick sensation in the region that is supplied by the three nerves along with adequate motor block, 30 minutes after injection. The degree of motor block was evaluated 30 minutes after the block procedure. The results of the present study showed that the real time ultrasound guidance of PCB is more effective than ACB approach. Although the sensory blockade of the femoral nerve achieved equally by both techniques, the LFC and OBT nerves were faster and more effectively blocked with PCB technique. Also PCB group showed significant complete sensory block without need for general anesthesia, significant decrease in the post-operative VAS and significant increase time of first analgesic requirement as compared to the ACB group.Result and Conclusion:The present study demonstrates that blockade of lumber plexus by psoas compartment block is more effective in complete sensory block without general anesthesia supplementation in addition to decrease post-operative analgesic requirement than adductor canal block.

The distribution of anesthetic in the case of psoas-compartment block according to the data of radiography

Anesthesia in hip surgery faces many problems due to age and comorbidity, the necessity of reliable intra- and perioperative anesthesia, thromboprophylaxis. That is why spinal and epidural anesthesia are so popular. However, a lot of potential risks are associated with these types of anesthesia: bradycardia, arterial hypertension, respiratory depression, postpuncture headache, epidural hematoma or abscess and so on. Peripheral nerves block both single application and prolong (via catheter) that include lumbar plexus and sciatic nerve, have some advantages comparing with spinal and epidural anesthesia. Several approaches are proposed to block effectively lumbar plexus in psoas-compartment. The goal: to assess the spreading of local anesthetic after the blockade in psoas-compartment via Capdevila approach. Methods: prolong blockades of psoas-compartment via catheter in lumbar plexus was used as a component of intra- and postoperative analgesia in case of total hip replacement in 21 adult patient. 10 ml of 1 % Lidocaine and 10 ml of contrast agent (iohexol) were injected in catheter at the end of operative procedure. Then standard AP radiography was performed with following assessment of contrast agent spreading along the vertebral bodies. Results: spreading of contrast agent along spinal segments LIII and LIV were found in all (100 %) patients, LV — 7 (33 %), LII — 5 (24 %), and along all, including LI–SI , — 2 (10 %) only. Moreover, two radiographic patterns were distinguished: 8 (38 %) patients had equal distribution of contrast agent along spine, but in 13 (62 %) patients contrast agent was predominantly concentrated near LIII and LIV bodies. Conclusion: 20 ml of solution always envelope LIII and LIV spinal segments, other segments may require additional blockade.

Continuous femoral nerve against psoas compartment block for analgesia in total knee arthroplasty

Background Total knee arthroplasty (TKA) is a surgical procedure that often demands potent analgesia. Anesthetists commonly rely on continuous epidural analgesia or psoas compartment block. After the American Society of Regional Anesthesia (ASRA) recent recommendation against the implication of deep regional blocks in the setting of perioperative anticoagulation, femoral nerve block might be a suitable alternative technique. Its effectiveness in TKA is a questionable issue. Our study is hypothesizing that continuous femoral block could provide an analgesic profile similar to continuous psoas compartment block. Patients and method Sixty patients undergoing TKA were randomly assigned into two groups to receive continuous femoral block or continuous psoas compartment block using ultrasound and nerve stimulation guidance. A bolus of 20 ml 0.25% levobupivacaine was injected through a perineural catheter in each group before surgery followed by a 5 ml bolus of 0.125%, and then 5 ml/h infusion at completion of surgery. A bolus of 5 ml 0.125% levobupivacaine was injected when numerical rating scale (NRS) was at least 5. In the first 24 h postoperatively, the median value and the interquartile range of the NRS at 1, 6, 12, and 24 h and after the first physiotherapy session were recorded as the primary end point. The total levobupivacaine and morphine consumption during the same 24-h period were the secondary end points, apart from patient's satisfaction with analgesia during hospitalization. Results The median and interquartile range of the NRS were 4.00 and 2.00 in the first hour, 4.00 and 1.5 in the sixth hour, 4.00 and 1.5 in the 12 th hour, 4.00 and 2.00 in the 24 th hour, and 4.00 and 2.00 after the first physiotherapy session, respectively, in the Fm group, and 3.00 and 3.00 in the first hour, 4.00 and 2.00 in the sixth hour, 4.00 and 1.5 in the 12 th hour, 3.00 and 2.5 in the 24 th hour, and 3.00 and 2.00 after the first physiotherapy session, respectively, in the Ps group. The total mean levobupivacaine and morphine consumption in the Fm and the Ps groups were 218. ± 7.89 vs. 216.6 ± 8.42 and 15.5 ± 4.01 vs. 13.50 ± 4.38, respectively, with no statistically significant difference between both the groups. The catheter insertion time was significantly shorter in the Fm group (8.53 ± 3.1 min) compared with (10.5 ± 3.2 min) the Ps group ( P = 0.021). Conclusion Continuous femoral nerve block provides a suitable alternative analgesic technique in patients undergoing TKA when psoas compartment block is unwarranted in the setting of perioperative anticoagulation as recommended by ASRA.

Early pharmacokinetic of ropivacaine without epinephrine after injection into the psoas compartment

Large amounts of local anaesthetics (LA) are used during psoas compartment block (PCB), especially if combined with sciatic nerve block. Data regarding early pharmacokinetics of ropivacaine for PCB are lacking, notably when a vasoconstrictive agent has not been added. PCB was established in 11 patients using 150 mg ropivacaine without epinephrine. Free and total arterial plasma concentrations of ropivacaine were measured at nine time points during the following 30 min. Also total protein, albumin, and α1-acid glycoprotein concentrations were analysed. Ropivacaine plasma concentrations were found in all patients within 30 s after injections. Maximum measured plasma concentrations were measured in all but two patients within the first 10 min. One patient experienced partial intravascular injection. Plasma concentrations showed wide inter-individual variability. Ranges of maximum measured plasma concentrations of total and free ropivacaine were 422-3905 and 5-186 ng ml(-1), respectively. The Pearson correlation between total and free concentrations was 0.96. No obvious relationship between concentrations of different plasma proteins (total protein, albumin, α1-acid glycoprotein) and ropivacaine concentrations was found. Maximal 5% of the measured ropivacaine was unbound. All blocks were successful and no signs of toxicity were observed. Maximum measured plasma concentrations of ropivacaine after PCB must be expected within 10 min. Although plasma concentrations stayed below toxic thresholds, our study demonstrates the risk of this regional anaesthesia technique. The clinical study was not registered because enrolment of study patients occurred in 2006.