Peripheral nerve blocks for postoperative pain after major knee surgery

Novel lumbar plexus block versus femoral nerve block for analgesia and motor recovery after total knee arthroplasty

This study aimed to compare the postoperative analgesic efficacy and motor recovery of a novel lumbar plexus block (LPB) with that of a femoral nerve block (FNB) after total knee arthroplasty (TKA). Forty patients who underwent TKA were randomised equally into an lumbar plexus and sciatic nerve (LS) group (receiving novel LPB) and an femoral and sciatic nerves (FS) group (receiving FNB). The assessed variables were the onset time of pain, time to the first analgesic request, pain scores, motor block at 6, 12, and 24 h after TKA, and the number of patients receiving successful blockade for each branch of the lumbar plexus. In the LS group, the femoral, lateral femoral cutaneous, genitofemoral, iliohypogastric, ilioinguinal, and obturator nerves were blocked in 18, 20, 16, 18, 15, and 19 patients. Compared to the FS group, the LS group had a significantly shorter onset time of pain and time to the first analgesic request, a significantly larger total postoperative dose of sufentanil, significantly higher numeric rating scale scores for both rest and dynamic pain at 6, 12, and 24 h, and faster motor recovery. Novel ultrasound-guided LPB has a high blocking success rate and provides inferior postoperative analgesia, but faster motor recovery after TKA than FNB.

Perineural Administration of Dexmedetomidine in Axillary Brachial Plexus Block Provides Safe and Comfortable Sedation: A Randomized Clinical Trial

Dexmedetomidine prolongs the duration of regional block while its systemic sedative effect when administered perineurally is unknown. We aimed to evaluate the systemic sedative effect of perineural dexmedetomidine in patients after axillary brachial plexus block (ABPB). This single-blinded prospective randomized control trial included 80 patients undergoing wrist surgery receiving ABPB. Patients were randomized into two groups – Control group (CG, N = 40) and dexmedetomidine group (DG, N = 40). Both groups received ABPB with 20 ml of 0.5% Bupivacaine and 10 ml of 2% Lidocaine. Additionally, patients in DG received 100 mcg of dexmedetomidine perineurally. Depth of sedation was evaluated using Narcontrend Index (NI) and Ramsay Sedation Scale (RSS) immediately after ABPB and in several time points up to 120 min. Duration of block as well as patient satisfaction with sedation was evaluated using a postoperative survey. Our results showed that NI and RSS statistically differed between groups, presenting a deeper level of sedation during the first 90 min in DG compared to controls, P < 0.001. In the first 10 to 60 min after ABPB the median RSS was 4 (IQR within median) and median NI was 60 (IQR 44–80) in DG group, in contrast to CG patients where median RSS was 2 (IQR within median) and median NI was 97 (IQR 96–98) throughout surgery. The level of sedation became equal in both groups 90 and 120 min after ABPB when the median NI value was 98 (97–99) in DG and 97.5 (97–98) in CG, P = 0.276, and the median RSS was 2 (IQR within median) in both groups, P = 0.128. No significant intergroup differences in hemodynamic or respiratory parameters were found. Patients in DG expressed satisfaction with sedation and 86.5% noted that the sensation was similar to ordinary sleep. In DG mean duration of motor block was 13.5 ± 2.1 h and sensory block was 12.7 ± 2.8 h which was significantly longer compared to CG 6.3 ± 1.5 h, P < 0.001 and 6.4 ± 1.8 h, P < 0.001. We found that beside prolongation of analgesia, perineural administration of dexmedetomidine might provide rather safe and comfortable sedation with no significant effect on hemodynamic or respiratory stability and yields a high level of patient satisfaction.

What is the minimum effective anesthetic volume (MEAV90) of 0.2% ropivacaine required for ultrasound-guided popliteal-sciatic nerve block?

Background and Aims:

Popliteal-Sciatic nerve block under Ultrasound Guidance (USG) using a local anesthetic agent like Ropivacaine is an established technique for providing analgesia and muscle relaxation for lower limb surgeries with minimal untoward events. Establishing the minimal volume of 0.2% ropivacaine required to provide intraoperative and postoperative analgesia will further reduce the drug requirements and adverse effects toward the patient.

Material and Methods:

This randomized prospective observational blinded study was done in a tertiary care referral hospital in South India over 9 months from August 2017 till April 2018. The block was performed on all recruited patients under ultrasound guidance with a starting volume of 16 ml 0.2% ropivacaine. Duration of time for loss of pin-prick sensation around the sole of the foot (tibial nerve) and the lateral malleolus (common peroneal nerve) was noted. If successful, the volume of the drug for subsequent patients was randomized by lottery method to either be kept the same or reduced. If the block failed, the subsequent patient recruited would have an increased volume of drug injected.

Results:

By Probit regression analysis using the biased coin up-and-down method we found that 9.3 ml (MEAV90) of 0.2% ropivacaine was sufficient for providing adequate analgesia. Factors such as patient age or weight had no role in efficacy of the block. There were no adverse effects such as allergy to the drug or systemic toxicity noted in the studied patients.

Conclusion:

9.3 ml of 0.2% ropivacaine is sufficient to provide analgesia (assessed by pin-prick) in 90% of patients undergoing popliteal-sciatic block for lower limb surgeries.

Does the performance of lower limb peripheral nerve blocks differ among orthopedic sub-specialties? A single institution experience in 246 patients

OBJECTIVES

Continuous peripheral nerve blocks (cPNBs) have shown promising results in pain management after orthopaedic surgeries. However, they can be associated with some risks and limitations. The purpose of this study is to describe our experience with the cPNBs regarding efficacy and adverse events in patients undergoing orthopedic surgeries on the lower extremity in different subspecialties.

METHODS

This is a prospective cohort study on collected data from perineural catheters for pain management after orthopedic surgeries in lower limbs. Catheters were placed by experienced anesthesiologists using sterile technique. After an initial bolus dose of 10-20 mL ropivacaine 0.5% (weight adjusted), the catheters were secured and connected to disposable mechanical infusion pumps with ropivacaine 0.2% (basal infusion rate = 6 mL/h; weight adjusted (0.2 mL/kg/h)). After catheterization, the patients were examined daily, by specially educated acute pain service nurses. Pro re nata (PRN) or fixed boluses (10 mL bupivacaine 0.25%; weight adjusted) with an upper limit of 4 times/day, were administered if indicated. Patients' demographic data, physiological status, and pre-op intake of opioids and other analgesics were registered. The severity of post-operative pain was assessed with 'Numeric Rating Scale' (NRS) and 'Face, legs, Activity, Cry, Consolability' (FLACC) scale for adults and children, respectively. The need for additional opioids and possible complications were registered.

RESULTS

We included 547 catheters of 246 patients (Range 1-10 catheters per patient). Overall, 115 (21%) femoral, 162 (30%) saphenous, 66 (12%) sciatic, and 204 (37%) popliteal sciatic nerve catheter were used. 452 (83%) catheters were inserted by a primary procedure, 61(11%) catheters employed as a replacement, and 34 catheters (6.2%) used as a supplement. For guiding the catheterization, ultrasound was applied in 451 catheters (82%), nerve stimulator in 90 catheters (16%), and both methods in 6 catheters (1.1%). The median duration a catheter remained in place was 3 days (IQR = 2-5). The proportion of catheters with a duration of two days was 81, 79, 73, and 71% for femoral, sciatic, saphenous, and popliteal nerve, respectively. In different subspecialties, 91% of catheters in wound and amputations, 89% in pediatric surgery, 76% in trauma, 64% in foot and ankle surgery, and 59% in limb reconstructive surgery remained more than two days. During first 10 days after catheterization, the proportion of pain-free patients were 77-95% at rest and 63-88% during mobilization, 79-92% of the patients did not require increased opioid doses, and 50-67% did not require opioid PRN doses. In addition to 416 catheters (76%), which were removed as planned, the reason for catheter removal was leaving the hospital in 27 (4.9%), loss of efficacy in 69 (13%), dislodgement in 23 (4.2%), leakage in 8 (1.5%), and erythema in 4 catheters (0.73%). No major complication occurred.

CONCLUSIONS

After orthopaedic procedures, cPNBs can be considered as an efficient method for improving pain control and minimizing the use of additional opioids. However, the catheters sometimes might need to be replaced to achieve the desired efficacy.

A review of peripheral nerve blocks for cesarean delivery analgesia

Peripheral nerve blocks have a unique role in postcesarean delivery multimodal analgesia regimens. In this review article, options for peripheral nerve blocks for cesarean delivery analgesia will be reviewed, specifically paravertebral, transversus abdominis plane, quadratus lumborum, iliohypogastric and ilioinguinal, erector spinae, and continuous wound infiltration blocks. Anatomy, existing literature evidence, and specific areas in need of future research will be assessed. Considerations for local anesthetic toxicity, and for informed consent for these modalities in the context of emergency cesarean deliveries, will be presented.

Fixation of intracapsular fracture of the femoral neck using combined peripheral nerve blocks and transthoracic echocardiography in a patient with severe obstructive hypertrophic cardiomyopathy: a case report

Background

Hypertrophic obstructive cardiomyopathy (HOCM) is a type of hypertrophic cardiomyopathy associated with left ventricular outflow tract stenosis. The increased pressure gradients across the left ventricular outflow tract in patients with HOCM could lead to circulatory collapse. We describe our experience with perioperative management under femoral nerve block (FNB), lateral femoral cutaneous nerve block (LFCNB), and transthoracic echocardiography (TTE) monitoring during open reduction and internal fixation of a femoral neck fracture in a patient with severe HOCM.

Case presentation

A 72-year-old man, who was indicated to undergo open reduction and internal fixation of an intracapsular femoral neck fracture, had a history of treatment for hypertension and HOCM. He had heart failure for 4 years and was hospitalized several times. He was resuscitated after ventricular fibrillation and received an implantable cardioverter-defibrillator at that time. He also had severe physical limitations (New York Heart Association class III). We selected FNB and LFCNB as the methods for anesthesia and injected 0.25% levobupivacaine (20 mL) around the femoral nerve and 0.25% levobupivacaine (10 mL) into the lateral femoral nerve region. He underwent TTE during the perioperative period, which enabled us to perform hemodynamic and morphological evaluations of the heart. The intraoperative TTE findings remained stable from before the induction of anesthesia to the patient’s exit from the operating room. Postoperatively, his hemodynamic parameters continued to remain stable.

Conclusions

In this case, FNB and LFCNB contributed to hemodynamic stability during non-cardiac surgery. Additionally, TTE was useful for the perioperative evaluation of cardiac hemodynamics and morphology in our patient with severe HOCM.

Catheter use in regional anesthesia: pros and cons

Continuous peripheral nerve blocks refer to a local anesthetic solution administered via perineurally placed catheters in an effort to extend the benefits of a single-shot peripheral nerve block. They offer several advantages in the postoperative period including excellent analgesia, reduced opioid consumption and associated side effects, enhanced rehabilitation and improved patient satisfaction. The current trend towards less invasive, one-day surgery and enhanced recovery programs may decrease the requirement of catheter use. Prolonged motor block in particular is associated with undesirable outcomes. Should we routinely use continuous peripheral nerve blocks in our daily practice? This PRO-CON debate aims at answering the question from the experts' perspectives. Fascial compartment and wound catheters are outside the scope of this debate.

Continuous adductor canal blockade facilitates increased home discharge and decreased opioid consumption after total knee arthroplasty

BACKGROUND

There is a growing interest in avoiding discharging patients to rehab to maximize outcome and minimize complications after total knee arthroplasty (TKA). In addition, use of postoperative pain pathways that minimize opioid use is critical amidst the current opioid epidemic. However, the ideal pain regimen after TKA has yet to be determined.

METHODS

From July 1, 2013 to October 1, 2014 two perioperative pathways were used to address surgical pain. These included either a single shot femoral nerve block plus liposomal bupivacaine pericapsular injection (FNB + LB-PAI) or adductor canal catheter plus posterior capsule single shot block (ACC + iPACK), each with an oral analgesic protocol. Little modification occurred with regard to surgical technique, postoperative medications, or postoperative physical therapy (PT).

RESULTS

Overall, 264 unilateral, primary TKA patients (146 FNB + LB-PAI, 118 ACC + iPACK) were included. ACC + iPACK patients had a shorter median length of stay (LOS, 2.0 vs 3.0, p < 0.001), more discharges home (79.7% vs 67.8%, p = 0.002), and less median opioid consumption (IV morphine equivalents, IVME, 20.0 vs 44.1, p < 0.001) than the FNB + LB-PAI group. In multivariable analysis, use of ACC + iPACK remained independently associated with shorter LOS, increased discharge home, and less IVME consumed when controlling for confounding variables. ACC + iPACK patients also had fewer opioid related adverse events (0.8 vs 5.5, p = 0.045) and a lower rate of MUA (0.8% vs 6.2%, p = 0.026).

CONCLUSIONS

We recommend ACC + iPACK with a multimodal oral analgesic protocol as the primary postoperative analgesia in enhanced recovery TKA protocols. This resulted in an easier recovery with fewer complications.

LEVEL OF EVIDENCE

Level III.

Successful use of femoral nerve block with dexmedetomidine for fracture fixation of an intracapsular fracture of the femoral neck in a patient with severe aortic stenosis: a case report

We described a case in which femoral nerve block (FNB) and lateral femoral cutaneous nerve block (LFCNB) with dexmedetomidine (DEX) was useful for open reduction and internal fixation (ORIF) of a femoral neck fracture in a patient with severe aortic stenosis. Cardiac surgery had been recommended but was declined by the patient. Thus, ORIF was selected because of the patient's concomitant severe aortic stenosis. The anesthesia method used was FNB plus LFCNB with DEX, which achieved adequate local anesthesia. DEX was used to avoid respiratory depression because this patient has pulmonary hypertension. This patient had been sedative up to the end of surgery. Total operating time was 51 min, and the patient's hemodynamics were stable throughout the perioperative period. There were no complications. In this case, anesthesia using a nerve block with DEX contributed to the safety of noncardiac surgery in a patient with severe cardiac disease under conservative treatment during the perioperative period.

Patient Satisfaction After Total Knee Arthroplasty: A Realistic or Imaginary Goal?

This article summarizes the current literature regarding patient satisfaction after total knee arthroplasty. In 10% to 15% of cases, the operation has not met the patients' expectations. The causes of this dissatisfaction are multifactorial, and include patient-related factors, details related to the surgical procedure and prosthesis chosen, perioperative factors, and factors associated with nursing and general medical care. However, surgeons must bear the brunt of patients' dissatisfaction. This dissatisfaction erodes the doctor-patient relationship, and may have implications in an emerging health care economy in which doctors and hospitals are reimbursed based on both clinical outcome and patient satisfaction.

Ultrasound-Guided Motor-Sparing Knee Blocks for Postoperative Analgesia Following Total Knee Arthroplasty: A Randomized Blinded Study

BACKGROUND

Pain following total knee arthroplasty (TKA) is often severe and can inhibit rehabilitation. Motor-sparing analgesic techniques such as periarticular infiltrations and adductor canal blocks have been popularized for knee analgesia since they preserve motor strength and permit early mobilization. Our primary objective was to compare the duration of analgesia from motor-sparing blocks with that of a standard periarticular infiltration. We used the time to first rescue analgesia as the end point.

METHODS

We randomized 82 patients scheduled for elective TKA to receive either the preoperative motor-sparing block (0.5% ropivacaine, 2.5 μg/mL of epinephrine, 10 mg of morphine, and 30 mg of ketorolac) or intraoperative periarticular infiltration (0.3% ropivacaine, 2.5 μg/mL of epinephrine, 10 mg of morphine, and 30 mg of ketorolac). For the motor-sparing block, we modified the ultrasound-guided adductor canal block by combining it with a lateral femoral cutaneous nerve block and posterior knee infiltration. The patients, surgeons, anesthetists administering the blocks, and outcome assessors all remained blinded to group allocation. Our primary outcome was duration of analgesia (time to first rescue analgesia). Secondary outcomes included quadriceps strength, function, side effects, satisfaction, and length of hospital stay.

RESULTS

The duration of analgesia was significantly longer (mean difference, 8.8 hours [95% confidence interval = 3.98 to 13.62], p < 0.01) for the motor-sparing-block group (mean [and standard error], 18.1 ± 1.7 hours) compared with the periarticular infiltration group (mean, 9.25 ± 1.7 hours). The infiltration group had significantly higher scores for pain at rest for the first 2 postoperative hours and for pain with knee movement at 2 and 4 hours. There were no significant differences between groups with regard to any other secondary outcomes.

CONCLUSIONS

In patients undergoing a TKA, a motor-sparing block provides longer analgesia than periarticular infiltration with retention of quadriceps muscle strength, function, patient satisfaction, and a short hospital stay.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.