Peripheral Nerve Blocks and Continuous Catheter Techniques

Comparison of the Efficacy of Continuous Femoral Nerve Block With Epidural Analgesia for Postoperative Pain Relief After Unilateral Total Knee Replacement

Introduction With recent developments in postoperative pain management after total knee replacement (TKR), the continuous femoral nerve block is becoming a common practice. The purpose of this study was to compare a femoral nerve block with time-tested epidural analgesia in a tertiary care setup in a developing country. Methodology A randomized control trial took place at Shifa International Hospital (SIH), Islamabad, Pakistan. Sixty patients, aged 40 to 90 years old, 12 males and 48 females, who were undergoing unilateral TKR for osteoarthritis in American Society of Anesthesiologists (ASA) physical status classes I and II, weighing between 50 and 99 kg, and fully able to understand and respond to the numeric rating scale (NRS) were included in the study. While patients belonging to ASA physical status class ≥3, with chronic opiate therapy, having allergies to local anesthetics or equipment material, or with neuromuscular disease, were excluded from the study. Ethical approval was obtained, and patients were divided into two groups, with group A given epidural and group B given a femoral nerve block for pain management postop. Data were collected. The pain was recorded using the NRS at six, 12, and 24 hours postop. Results The results for six hours and 12 hours were found to be significant. Patients in group A had a lower NRS rating postop as compared to group B and required a lesser amount of additional boluses for pain management.  Conclusion The femoral nerve block is inferior to epidural analgesia for pain management after unilateral TKR in the first 24 hours, with a greater need for extra boluses to relieve pain.

Effect of local anesthetic volume (20 mL vs 30 mL ropivacaine) on electromyography of the diaphragm and pulmonary function after ultrasound-guided supraclavicular brachial plexus block: a randomized controlled trial

BACKGROUND AND OBJECTIVES

Diaphragmatic paralysis following supraclavicular brachial plexus block (SCBPB) is ascribed to phrenic nerve palsy. This study investigated the effect of 2 volumes of 0.375% ropivacaine on efficacy of block as a surgical anesthetic and as an analgesic and examined diaphragm compound muscle action potentials (CMAPs) and pulmonary function before and after SCBPB.

METHODS

Eighty patients scheduled for removal of hardware for internal fixation after healing of an upper limb fracture distal to the shoulder were randomized to receive ultrasound-guided SCBPC for surgical anesthesia with 20 mL (Group A) or 30 mL (Group B) 0.375% ropivacaine. The latency and amplitude of diaphragm CMAPs and forced vital capacity (FVC), FVC% predicted, and forced expiratory volume in 1 s (FEV1) were measured before and 30 min after SCBPB.

RESULTS

Block success as primary anesthetic in addition to analgesia was 81% in Group A and 91% in Group B. There were no obvious differences in the effectiveness of analgesia between the two groups. The mean time to onset of motor block was significantly longer in Group A (8.1±2.7 min) than in Group B (5.4 ± 2.8 min; p<0.05). The mean amplitude of the diaphragm CMAP was significantly lower in Group B than in Group A (p=0.03). The changes in FVC (Group A, - 8.1% vs Group B, -16.5%), FVC% (Group A, -8.0% vs Group B, -17.1%), and FEV1 (Group A, -9.5% vs Group B, -15.2%) from pre-SCBPB to post-SCBPB were significantly less in Group A than in Group B (all p=0.03).

CONCLUSIONS

The incidence rates of phrenic nerve palsy and diaphragm paralysis were reduced, and lung function was less impaired in patients who received 20 mL vs 30 mL of 0.375% ropivacaine without any differences in block success. Selecting a lower volume of anesthetic for nerve block may be especially beneficial in obese patients or patients with cardiopulmonary disease.

TRIAL REGISTRATION NUMBER

ChiCTR-IND-17012166.

Continuous Peripheral Nerve Blocks for Early Active Mobilization after Hand Surgery: Four Case Reports

Early active mobilization after hand surgery is extremely important for preventing scar tissue and adhesion. We examined four patients for whom continuous peripheral nerve blocks (CPNB) were used during and after hand surgery. This method was used for three median nerves and one ulnar nerve. A 2-cm incision was made at distal one-third of the forearm with local analgesia. The catheter tip was placed in the distal one-fourth of the forearm, and the hand surgery was begun. Early active mobilization and the self-rehabilitation exercise started immediately after the operation. The VAS scores during exercise were 0-2 (mean: 1.3); pain was controlled sufficiently. Regarding ROM, excellent results were obtained for tenolysis, with good results for arthrolysis. No infection or postoperative nerve compression was found. This method, using CPNB with a portable infusion pump, is effective and safe for use at home for postoperative pain control.

Continuous Femoral Nerve Blockade versus Epidural Analgesia for Postoperative Pain Relief in Knee Surgeries: A Randomized Controlled Study

Background:

Peripheral neural blockade provides effective analgesia with potentially less side effects than an epidural blockade. The present study was undertaken to compare continuous femoral nerve blockade (CFNB) with continuous epidural analgesia (CEA) for postoperative pain control in knee surgeries.

Materials and Methods:

The patients belonging to the American Society of Anesthesiologists Class I and II scheduled for various knee surgeries under spinal anesthesia were enrolled in this study. They were randomly divided into two equal groups of thirty patients each. The Group I patients received CFNB and in the Group II patients epidural catheter was placed preoperatively. Postoperatively, continuous infusion with 0.0625% bupivacaine and fentanyl 2 μg/ml started at 5 ml/h for 72 h in both the groups. Data on Visual Analog Scale (VAS) pain scores, hemodynamic changes, side effects at 0, 1, 6, 12, 24, 36, 48, 60, and 72 h and requirement of analgesic doses for the first 24 h of the surgery were noted.

Results:

In both the groups, pain was well controlled, mean VAS of pain were 0.2, 0.6, 2.47, 2.07, 2.73, 1.5, 1.43, 1.37, and 1.3 for femoral and 0.13, 0.93, 2.57, 2.17, 2.33, 1.6, 1.43, 1.30, and 1.33 for epidural group during 0, 1, 6, 12, 24, 36, 48, 60, and 72 h which was not statistically significant. Hemodynamics were stable throughout in both the groups. The patients in CEA had more incidences of pruritus and urinary retention.

Conclusion:

CFNB provides postoperative analgesia equivalent to that obtained with a CEA but with fewer side effects.

Meta-analysis of epidural analgesia versus peripheral nerve blockade after total knee joint replacement

BACKGROUND

Postoperative pain after major knee surgery can be severe. Our aim was to compare the outcomes of epidural analgesia and peripheral nerve blockade (PNB) in patients undergoing total knee joint replacement (TKR). Moreover, we aimed to compare outcomes of adductor canal block (ACB) with those of femoral nerve block (FNB) after TKR.

METHODS

We conducted a systematic search of electronic information sources, including MEDLINE; EMBASE; CINAHL; and the Cochrane Central Register of Controlled Trials (CENTRAL). We applied a combination of free text and controlled vocabulary search adapted to thesaurus headings, search operators, and limits in each of the above databases. Pain intensity assessed on visual analogue scale (VAS), nausea and vomiting, systolic hypotension, and urinary retention was the reported outcome parameters.

RESULTS

We identified 12 randomised controlled trials (RCTs) comparing outcomes of epidural analgesia and PNB reporting a total of 670 patients. There was no significant difference between two groups in VAS scores at 0-12 h (MD -0.48; 95 % CI -1.07-0.11, P = 0.11), 12-24 h (MD 0.04; 95 % CI -0.81-0.88, P = 0.93), and 24-48 h (MD 0.16; 95 % CI -0.08-0.40, P = 0.19). However, epidural analgesia was associated with significantly higher risk of postoperative nausea and vomiting (RR 1.65; 95 % CI, 1.20-2.28, P = 0.002), hypotension (RR 1.76; 95 % CI, 1.26-2.45, P = 0.0009), and urinary retention (RR 4.51; 95 % CI, 2.27-8.96, P < 0.0001) compared to PNB. Moreover, pooled analysis of data from 6 RCTs demonstrated no significant difference in VAS score between ACB and FNB at 24 h (MD -0.00; 95 % CI, -0.56-0.56, P = 0.99) and 48 h (MD -0.06; 95 % CI, -0.14-0.03, P = 0.23).

CONCLUSIONS

PNB is as effective as epidural analgesia for postoperative pain management in patients undergoing TKR. Moreover, it is associated with significantly lower postoperative complications. ACB appears to be an effective PNB with similar analgesic effect to FNB after TKR. Future RCTs may provide better evidence regarding knee range of motion, length of hospital stay, and neurological complications.

A novel suture method to place and adjust peripheral nerve catheters

We have developed a peripheral nerve catheter, attached to a needle, which works like an adjustable suture. We used in‐plane ultrasound guidance to place 45 catheters close to the femoral, saphenous, sciatic and distal tibial nerves in cadaver legs. We displaced catheters after their initial placement and then attempted to return them to their original positions. We used ultrasound to evaluate the initial and secondary catheter placements and the spread of injectate around the nerves. In 10 cases, we confirmed catheter position by magnetic resonance imaging. We judged 43/45 initial placements successful and 42/43 secondary placements successful by ultrasound, confirmed in 10/10 cases by magnetic resonance imaging.

A novel concept for continuous peripheral nerve blocks. Presentation of a new ultrasound-guided device

BACKGROUND

Existing techniques for placing and maintaining the position of peripheral nerve catheters are associated with variable success rates and frequent secondary failures. These factors may affect the clinical efficacy and usefulness of peripheral nerve catheters.

METHODS

We developed a new concept and prototype for ultrasound-guided in-plane positioning and readjustment of peripheral nerve catheters (patent pending). The integrated catheter-needle prototype comprises three parts: a curved needle, a catheter with clear echogenic markings attached to the needle tail and a detachable hub allowing injection of local anesthetic while advancing the needle in the tissue. The system works like a suture and is introduced through the skin, passes in close relation to the nerve and exits through the skin. This allows in-plane ultrasound guidance throughout the procedure both during initial positioning as well as during later in-plane readjustment of the catheter. We tested the system in the popliteal region of two fresh cadavers in a preliminary proof of concept study.

RESULTS

Both initial placement and secondary readjustment were precise, judged by the catheter orifices placed close to the sciatic nerve in the popliteal fossa. Circumferential spread of 3-ml isotonic saline around the sciatic nerve was observed on ultrasound images in both conditions.

CONCLUSION

Preliminary proof of concept of this novel method demonstrates that precise in-plane ultrasound-guided initial placement and secondary in-plane readjustment is possible in fresh cadavers. Future studies should address the clinical efficacy and usefulness of this novel concept.

Acute pain service: the journey in a developing country setting

BACKGROUND

In India, acute pain service (APS) is in nascent stage because of lesser importance given to pain management. After establishing an APS in our hospital, we conducted a prospective audit (2008-2011) with an aim to regularly assess the efficacy of techniques on pain scores, muscle power, and adverse effects.

METHODS

The audit was undertaken in three phases. An assessment of the existing system and recommendation to modify the APS was undertaken in phase I. In phase II, an APS team was constituted and audits were conducted at six monthly intervals for formation of the protocol. Subsequently in phase III, yearly audits were undertaken that led to the development of a final APS.

RESULTS

There was a steady increase in the number of patients availing APS in intravenous patient-controlled analgesia (IVPCA), epidural analgesia (EA), and continuous peripheral nerve block (CPNB). At the same time, the average visual analogue score (VAS) decreased significantly as the year progressed. While the VAS score did not differ significantly between EA and CPNB, it was less compared with IVPCA. Introduction of regional analgesic techniques played a major role in improving the pain scores.

CONCLUSION

Implementation of APS resulted in reduced pain scores in our surgical patients. Proper planning, role allocation, formation, and adherence to protocols as well as undertaking regular audit resulted in improving the quality of APS.

Analgesic techniques in hip and knee arthroplasty: from the daily practice to evidence-based medicine

Total hip arthroplasty (THA) and total knee arthroplasty (TKA) are major orthopedic surgery models, addressing mainly ageing populations with multiple comorbidities and treatments, ASA II–IV, which may complicate the perioperative period. Therefore effective management of postoperative pain should allow rapid mobilization of the patient with shortening of hospitalization and social reintegration. In our review we propose an evaluation of the main analgesics models used today in the postoperative period. Their comparative analysis shows the benefits and side effects of each of these methods and guides us to how to use evidence-based medicine in our daily practice.

Brachial plexus anesthesia: A review of the relevant anatomy, complications, and anatomical variations

The trend towards regional anesthesia began in the late 1800s when William Halsted and Richard Hall experimented with cocaine as a local anesthetic for upper and lower limb procedures. Regional anesthesia of the upper limb can be achieved by blocking the brachial plexus at varying stages along the course of the trunks, divisions, cords and terminal branches. The four most common techniques used in the clinical setting are the interscalene block, the supraclavicular block, the infraclavicular block, and the axillary block. Each approach has its own unique set of advantages and indications for use. The supraclavicular block is most effective for anesthesia of the mid-humerus and below. Infraclavicular blocks are useful for procedures requiring continuous anesthesia. Axillary blocks provide effective anesthesia distal to the elbow, and interscalene blocks are best suited for the shoulder and proximal upper limb. The two most common methods for localizing the appropriate nerves for brachial plexus blocks are nerve stimulation and ultrasound guidance. Recent literature on brachial plexus blocks has largely focused on these two techniques to determine which method has greater efficacy. Ultrasound guidance has allowed the operator to visualize the needle position within the musculature and has proven especially useful in patients with anatomical variations. The aim of this study is to provide a review of the literature on the different approaches to brachial plexus blocks, including the indications, techniques, and relevant anatomical variations associated with the nerves involved.

Comparative study of ultrasound-guided continuous femoral nerve blockade with continuous epidural analgesia for pain relief following total knee replacement

Background:

Regional analgesia is widely used for total knee replacement surgeries (TKR) as it has lesser side-effects and better analgesic efficacy when compared with traditional oral analgesics. Peripheral nerve blockade has also been utilized, including continuous infusion techniques. With the use of ultrasound, the needle and catheter placement can be done accurately under real-time guidance. This may prove a more suitable approach compared with the epidural technique.

Aims:

Post-operative analgesia in TKR patients was compared between continuous epidural analgesia (CEA) and continuous femoral block (CFB) techniques. VAS scores and use of rescue analgesic were used as parameters. Secondary aims included comparison of rehabilitation scores and side-effects in the form hypotension, vomiting, itching and urinary retention.

Settings and Design:

Randomised, controlled, non-blinded study done in a tertiary care private hospital.

Methods:

Forty-two patients fulfilling the study criteria were randomised into the CEA and CFB groups. In total, four patients: three in the CFB group and one in the CEA group, were excluded because of catheter migration.

Statistical Analysis:

Mean VAS score at 6, 6–24, 24–48 and 48–72 h were considered. Significance was assessed at the 5% level.

Results and Conclusion:

VAS scores were significantly high (P=0.001) in the femoral group at 6 h, after which there was a declining trend, and scores were essentially similar from 24 h. Common side-effects were more common in the CEA group. Our study shows that CFB gives equivalent analgesia compared with CEA in TKR patients with clinically meaningful decrease in side-effects.

Strategies Aimed at Preventing Chronic Post-surgical Pain: Comprehensive Perioperative Pain Management after Total Joint Replacement Surgery

PURPOSE

Chronic post-surgical pain (CPSP) is a frequent outcome of musculoskeletal surgery. Physiotherapists often treat patients with pain before and after musculoskeletal surgery. The purposes of this paper are (1) to raise awareness of the nature, mechanisms, and significance of CPSP; and (2) to highlight the necessity for an inter-professional team to understand and address its complexity. Using total joint replacement surgeries as a model, we provide a review of pain mechanisms and pain management strategies.

SUMMARY OF KEY POINTS

By understanding the mechanisms by which pain alters the body's normal physiological responses to surgery, clinicians selectively target pain in post-surgical patients through the use of multi-modal management strategies. Clinicians should not assume that patients receiving multiple medications have a problem with pain. Rather, the modern-day approach is to manage pain using preventive strategies, with the aims of reducing the intensity of acute postoperative pain and minimizing the development of CPSP.

CONCLUSIONS

The roles of biological, surgical, psychosocial, and patient-related risk factors in the transition to pain chronicity require further investigation if we are to better understand their relationships with pain. Measuring pain intensity and analgesic use is not sufficient. Proper evaluation and management of risk factors for CPSP require inter-professional teams to characterize a patient's experience of postoperative pain and to examine pain arising during functional activities.

Continuous peripheral nerve blockade for inpatient and outpatient postoperative analgesia in children

BACKGROUND

This is an audit of the continuous peripheral nerve blockade (CPNB) program that was implemented at our institution to provide postoperative analgesia after orthopedic procedures in children.

METHODS

We reviewed the departmental regional anesthesia registry and the medical records of consecutive children who received CPNB for postoperative analgesia at The Children's Hospital of Philadelphia between February 2003 and July 2006. Patients were prospectively followed until cessation of the effects of CPNB and/or resolution of any related complications. Data collected contemporaneously included presence of sensory and motor blockade, pain scores in inpatients, opioid administration, and complications related to CPNB.

RESULTS

A total of 226 peripheral nerve catheters were placed in 217 patients. One hundred eight patients (112 catheters) were discharged home with CPNB. The ages ranged from 4 to 18 yr (13.7 +/- 3.4). Local anesthetic solution (0.125% bupivacaine [n = 164], 0.1% ropivacaine [n = 12], or 0.15% ropivacaine [n = 27]) was infused at an initial rate of 2-12 mL/h based on patients' weights and locations of catheters. The mean duration of local anesthetic infusion was 48.4 +/- 29.3 h (range 0-160 h). The percentage of patients who did not require any opioids in the first 8, 24, and 48 h after surgery was 56%, 26%, and 21%, respectively. The incidence of nausea and vomiting was 14% (13% in outpatients, 15% in inpatients). Complications were noted in 2.8% of patients. Three patients had prolonged numbness (>24 h) that resolved spontaneously; one developed superficial cellulitis that resolved with a course of antibiotics; one had difficulty removing the catheter at home and one developed tinnitus 24 h after starting CPNB that resolved quickly after clamping of the catheter followed by removal.

CONCLUSION

It is feasible to implement a CPNB program to provide an alternative method of inpatient and outpatient postoperative analgesia after orthopedic surgery in children when appropriate expertise is available. Patient and family education along with frequent follow-up are crucial to detect and address adverse events promptly.

Complications and Adverse Effects Associated with Continuous Peripheral Nerve Blocks in Orthopedic Patients

BACKGROUND

The increasing popularity of continuous peripheral nerve blocks (CPNBs) warrants further study of their adverse effects and complications.

METHODS

Anterior sciatic, femoral, and interscalene brachial plexus CPNBs were performed preoperatively using standardized catheter techniques in orthopedic patients prior to general or spinal anesthesia. Complications and adverse effects related to CPNBs were prospectively evaluated.

RESULTS

We analyzed 1398 CPNBs in 849 consecutive patients (mean age 65 +/- 13 yr) between 2002 and 2004. Two-hundred-twenty-one patients received interscalene, 628 patients femoral, and 549 sciatic CPNBs, respectively. In all the latter patients, we performed both femoral and sciatic CPNBs. Overall, there were 9 cases of local inflammation at the insertion site (0.6%), and 3 local infections (pustule) (0.2%, all femoral CPNBs). In one patient undergoing a femoral technique, a retroperitoneal hematoma led to compression injury of the femoral nerve. Complete denervation of the quadriceps femoris muscle was confirmed by electroneuromyography. No other major neurological complications were noted. There was one case of methemoglobinemia associated with an interscalene CPNB. Vascular puncture occurred in approximately 6% of patients undergoing femoral and sciatic CPNBs. Catheter rupture was noted in one patient.

CONCLUSIONS

Our results add to the evidence that major complications from CPNBs are rare. However, minor adverse effects associated with CPNBs may be more common.

Regional anaesthesia and perioperative outcome

PURPOSE OF REVIEW

The ongoing debate on the outcome benefits of regional anaesthesia and analgesia over general anaesthesia and systemic analgesia has led to a large number of recently published papers, in particular systematic reviews and meta-analyses that justify a review of the current status of the debate.

RECENT FINDINGS

Meta-analyses have shown consistently improved analgesia with epidural techniques, but the results are by far less consistent with regard to other outcomes, in particular morbidity and mortality. Specific outcomes in specific types of surgery, however, such as bowel recovery after abdominal surgery, can be improved by neuraxial blockade, which also remains the technique of choice for obstetric analgesia and anaesthesia. In certain indications, peripheral nerve blocks may have the potential to replace neuraxial blocks while maintaining the benefits of the regional technique, such as paravertebral blocks for thoracotomies.

SUMMARY

Although there are a considerable number of recent publications on the topic, the complex issues around the effect of regional anaesthesia on outcome is not completely resolved, possibly because the data are often not procedure specific. In addition, however, it may be that our current literature cannot provide a definitive answer.

Continuous peripheral nerve block in combat casualties receiving low-molecular weight heparin

BACKGROUND

Continuous peripheral nerve block (CPNB) is an important therapeutic tool in the anaesthetic and analgesic management of combat casualties at Walter Reed Army Medical Center (WRAMC). We describe our experience using CPNB techniques in combat trauma patients treated with low-molecular weight heparin (LMWH). Guidelines used at our institution for managing CPNB catheters in patients being treated with LMWH are introduced.

METHODS

From March 2003 to April 2005, 187 combat casualties treated by the WRAMC regional anaesthesia/acute pain section using CPNB were evaluated retrospectively by electronic chart review. Patient characteristic data, CPNB type, duration of CPNB, indication for LMWH [enoxaparin sodium injection (Lovenox-Sanofi Aventis, Bridgewater, NJ, USA)], enoxaparin dose (mg) before and after catheter insertion and removal, time from CPNB placement and removal to enoxaparin dose, and complications were recorded.

RESULTS

Median enoxaparin dose and time given before catheter insertion were 30 mg and 21 h, respectively. Median enoxaparin dose was also 30 mg given a median of 12 h after peripheral nerve catheter placement. Catheters remained in situ for a median of 8 days (range 1-33 days). Catheter specific complications were infrequent and identified in 7 (3.7%) patients (two catheter malfunction-kinking, catheter tip dislodgement in situ, two superficial catheter site infections and two catheter dislocations). There were no catheter-related bleeding complications evident in this study.

CONCLUSIONS

Information regarding the safety of CPNB in patients treated with LMWH for perioperative venous thromboembolism prevention is scarce. Our initial experience with CPNB and concurrent LMWH has not been complicated by catheter-related bleeding.