Color Doppler ultrasonography of an agitated solution is predictive of accurate catheter placement for a continuous popliteal sciatic nerve block.

BACKGROUND: Continuous peripheral nerve catheters (PNCs) have been shown to provide superior postoperative analgesia, decrease opioid consumption, and improve patient satisfaction compared with single injection techniques. In order to achieve success and reliability, accurate catheter positioning is an essential element of PNC placement. An agitated solution of normal saline, D5W, or a local anesthetic solution can be produced by the introduction of air to the injectate, creating air bubbles that can enhance ultrasonographic visualization and possibly improve block success. METHODS: Eighty-three patients were enrolled. Ultrasound-guided continuous popliteal sciatic nerve blocks were performed by positioning the tip of a Tuohy needle between the tibial and common peroneal branches of the sciatic nerve and threading a catheter. An agitated local anesthetic solution was injected through the catheter, viewed with color Doppler ultrasound and video recorded. A peripheral block score (lower score = greater blockade, range 0-14) was calculated based upon the motor and sensory testing at 10, 20, and 30 min after block completion. The color Doppler agitation coverage pattern for the branches of the sciatic nerve was graded as follows: complete (> 50%), partial (> 0%, ≤ 50%), or none (0%). RESULTS: The degree of nerve blockade at 30 min as judged by median (10th, 90th percentile) peripheral block score was significant for partial or complete color Doppler coverage of the sciatic nerve injectate compared to no coverage [3 (0, 7) vs 8 (4, 14); p < 0.01] and block onset was faster (p = 0.03). The block success was higher in groups with partial or complete coverage of the branches of the sciatic nerve vs no coverage (96% vs 70%; p = 0.02). CONCLUSIONS: Injection of an agitated solution through a popliteal sciatic perineural catheter is predictive of accurate catheter placement when partial or complete coverage of the sciatic nerve branches is visualized with color Doppler ultrasound. TRIAL REGISTRATION: NCT01591603.

Comprehensive Analysis of 13,897 Consecutive Regional Anesthetics at an Ambulatory Surgery Center.

Objective: The authors investigated a wide range of perioperative outcome measures in the context of a robust regional anesthesia practice. Design: Comprehensive review of a prospectively collected six-year database. Setting: Freestanding, academic ambulatory surgery center. Subjects: There were 13,897 consecutive regional anesthetics in 10,338 patients. Methods: We investigated patient satisfaction, postoperative nausea and vomiting (PONV), postoperative pain, catheter analgesia, and complications. Clinical risk factors were examined and presented as odds ratios for multiple outcome analyses including block success, patient satisfaction, PONV, and postoperative neurologic symptoms (PONS). Results: Decreased block success was associated with nerve stimulation alone (P < 0.001), obesity (P = 0.001), higher American Society of Anesthesiologists classification (ASA; P = 0.01), lower extremity blocks (P = 0.04), and male sex (P < 0.001). Decreased patient satisfaction was associated with poor catheter analgesia (P < 0.001), complications (P < 0.001), higher ASA (P = 0.001), and younger age (P = 0.008). PONV was associated with postoperative pain (P < 0.005), female sex (P < 0.001), general anesthesia (P < 0.001), younger age (P = 0.001), lack of catheter (P = 0.03), and lack of dexamethasone/clonidine (D + C) adjuncts (P = 0.01). Serious complications and unexpected hospitalizations were rare (<0.2%). D + C adjuncts, lower extremity blocks, clonidine (but not dexamethasone alone), and female sex were associated with PONS (all P < 0.001). Conclusions: A regional anesthesia-based practice in ambulatory surgery is an effective means of providing excellent postoperative analgesia and is associated with a low rate of PONV and unexpected admissions. Dexamethasone, clonidine, and their combination when combined with 0.5% ropivacaine may have mixed effects on PONS risk that warrant dose/concentration alterations of these three drugs in the context of off-label perineural adjunct use.

Duration of upper and lower extremity peripheral nerve blockade is prolonged with dexamethasone when added to ropivacaine: a retrospective database analysis.

BACKGROUND: Dexamethasone, when added to local anesthetics, has been shown to prolong the duration of peripheral nerve blocks; however, there are limited studies utilizing large numbers of patients. The purpose of this study was to examine the effect of adding dexamethasone to ropivacaine on duration of nerve blocks of the upper and lower extremity. METHODS: We reviewed 1,040 patient records collected in an orthopedic outpatient surgery center that had received an upper or lower extremity peripheral nerve block with ropivacaine 0.5% with or without dexamethasone and/or epinephrine. The primary outcome was duration of analgesia in upper or lower extremity blocks containing dexamethasone as an adjunct. Secondary outcomes included postoperative patient pain scores, satisfaction, and the incidence of block related complications. Linear and ordinal logistic regression models were used to examine the independent effect of dexamethasone on outcomes. RESULTS: Dexamethasone was observed to increase median block duration by 37% (95% confidence interval: 31-43%). The increased block duration persisted within body regions (upper and lower) and across a range of block types. Dexamethasone was also observed to reduce pain scores on the day of surgery (P = 0.001) and postoperative day 1 (P < 0.001). There was no significant difference in duration of nerve blocks when epinephrine (1:400,000) was added to 0.5% ropivacaine with or without dexamethasone. CONCLUSION: The addition of dexamethasone to 0.5% ropivacaine prolongs the duration of peripheral nerve blocks of both the upper and lower extremity.

The impact of peripheral nerve techniques on hospital stay following major orthopedic surgery.

OBJECTIVE: To determine the impact of regional anesthesia on hospital stay for selected orthopedic procedures compared with traditional pain control modalities. DESIGN: In an era of an increasing volume of orthopedic surgeries, pain modalities that can optimize patient care while minimizing hospital length of stay can have an impact on reducing hospital costs as well as increasing patient satisfaction and improving patient outcomes. Previous studies have shown the potential benefits of regional anesthesia over traditional intravenous (IV) narcotics in meeting these goals in selected orthopedic procedures. METHODS: We retrospectively analyzed the medical records of 494 patients who underwent major orthopedic procedures performed with traditional postoperative pain management alone (IV patient-controlled analgesia and oral narcotics), single injection peripheral nerve block (PNB), and continuous peripheral nerve block (CPNB) in order to determine the impact that different pain modalities might have on hospital length of stay. RESULTS: When compared with traditional pain control modalities, single PNB and CPNB were associated with decreased length of hospital stay, though results for specific surgeries varied. The hazard ratios for hospital discharge from a Current Procedural Terminology code-stratified, covariate (age, gender, and ASA status) adjusted Cox proportional hazards model for single PNB vs no PNB and for CPNB vs no PNB were 1.35 (95% confidence interval: 1.02-1.79) and 1.91 (95% confidence interval: 1.42-2.57), respectively, pointing toward earlier hospital discharge when PNBs were used. CONCLUSIONS Our retrospective case review showed that, overall, hospital lengths of stay tended to be shorter for orthopedic surgery patients receiving single PNB and CPNB than for those receiving no block and traditional pain management.

Continuous peripheral nerve block catheter infections in combat-related injuries: a case report of five soldiers from Operation Enduring Freedom/Operation Iraqi Freedom.

DESIGN: Case series. SETTING: Military medical facility providing acute care for soldiers injured while fighting in the war in Iraq and Afghanistan. OBJECTIVE: To report a series of infections related to use of continuous peripheral nerve catheters for postoperative pain control in the military polytraumatic setting. The analysis of the above infections includes similarities and differences in infection patterns and attempts to clarify possible risk factors for such infections to include duration of catheter placement, type of catheter, preprocedural antibiotics, and tunnel vs nontunneled catheters. The goal of this analysis is to assist in the development of protocols that may prevent future catheter infections. METHODS: Clinical data were obtained from five previously healthy male soldiers receiving acute care at Brooke Army Medical Center using continuous peripheral nerve catheters for postoperative pain for multiple and frequent procedures. RESULTS: In a total of six catheter infections, two were noted to have superficial skin infections while four were shown to have deep tissue involvement confirmed by imaging studies. All patients were started on initial or additional antibiotics after catheter removal. Three catheter infections, all with stimulating catheters, required surgical irrigation and debridement in the operating room. CONCLUSIONS: Continuous peripheral nerve catheters are not without complications and risks including infection. Duration of catheter use was the most significant factor with the development of a catheter-related infection in our series. This series also highlights how stimulating and nonstimulating catheter infections may present differently, as stimulating catheters may have a greater tendency to present as deep space infections with minimal superficial findings.

Brachial plexus entrapment of interscalene nerve catheter after uncomplicated ultrasound-guided placement.

We report on the case of an entrapped interscalene nerve catheter in a 46-year-old male undergoing left shoulder arthroscopic lysis of adhesions for a frozen shoulder. The catheter was placed under ultrasound guidance without any apparent complications. The continuous interscalene nerve block was successfully used as the primary anesthetic and for postoperative pain management. Upon attempted catheter removal, the patient experienced severe pain and paresthesias. Fluoroscopy revealed possible brachial plexus involvement, and surgery was performed to extract the catheter, which had become hooked and entrapped around the C5 nerve root and sheath.

Rectus sheath catheters for continuous analgesia after laparotomy--without postoperative opioid use.

OBJECTIVE: Opioid and epidural analgesia have been the mainstay for postoperative pain control following laparotomies, yet have many potential side effects, risks, and limitations. This case report offers an alternative to opioid as well as epidural analgesia, which may be beneficial in some patients. DESIGN: We report a case of a patient who underwent a laparotomy with extensive lysis of adhesions who was treated postoperatively with continuous bilateral rectus sheath catheters and multimodal adjuncts including gabapentin, clonidine, and nonsteroidal anti-inflammatories. RESULTS: We successfully used a novel, multimodal approach that avoided the use of epidural analgesia and postoperative opioids. The patient was extremely satisfied, reported minimal discomfort, ambulated early, advanced her diet quickly, and was discharged home after a short hospital stay. CONCLUSIONS: This report may be the first description of a successful multimodal postoperative analgesic regimen including continuous bilateral rectus sheath blocks without inpatient postoperative opioid use or epidural analgesia following a midline laparotomy.

The evolution of pain management in the critically ill trauma patient: Emerging concepts from the global war on terrorism.

BACKGROUND: The evolution of military medical care to manage polytrauma, critically ill-wounded warriors from the greater war on terrorism has been accompanied by significant changes in the diagnosis, management, and modulation of acute and chronic trauma-related pain. A paradigm shift in pain management includes early treatment of pain at the point of injury and throughout the continuum of care with a combination of standard and novel therapeutic interventions. These concepts are important for all critical care providers because they translate to most critically ill patients, including those resulting from natural disasters. Previous authors have reported a high incidence of moderate to severe pain and poor analgesia in intensive care units associated with sleep disturbances, tachycardia, pulmonary complications, increased stress response with thromboembolic incidents, and immunosuppression, increased intensive care unit and hospital stays, and needless suffering. Although opioids have traditionally been the cornerstone of acute pain management, they have potential negative effects ranging from sedation, confusion, respiratory depression, nausea, ileus, constipation, tolerance, opioid-induced hyperalgesia as well as potential for immunosuppression. Alternatively, multimodal therapy is increasingly recognized as a critical pain management approach, especially when combined with early nutrition and ambulation, designed to improve functional recovery and decrease chronic pain conditions. DISCUSSION: Multimodal therapy encompasses a wide range of procedures and medications, including regional analgesia with continuous epidural or peripheral nerve block infusions, judicious opioids, acetaminophen, anti-inflammatory agents, anticonvulsants, ketamine, clonidine, mexiletine, antidepressants, and anxiolytics as options to treat or modulate pain at various sites of action. SUMMARY: With a more aggressive acute pain management strategy, the military has decreased acute and chronic pain conditions, which may have application in the civilian sector as well.

Peripheral nerve blocks and anesthesia of the hand.

Regional anesthesia of the hand can be used in a vast array of hand injuries and minor operations. Local infiltration techniques require multiple injections and higher doses of anesthetic the that make them less preferable to peripheral nerve blocks. Regional anesthesia can be safe and effective as long as the provider has a firm understanding of the anatomy and technique. Multiple peripheral nerve blockade at the wrist can be a safe means of exploring complex wounds to the hand in both the emergency department and the operating room with minimal tissue distortion.