Regional anesthesia decreases complications and resource utilization in shoulder arthroplasty patients.

BACKGROUND: Regional anesthesia can be used as part of the anesthetic to optimize anesthesia and analgesia during shoulder arthroplasty, but little is known about the overall effect that regional anesthesia has on perioperative outcomes and resource utilization. We hypothesized that regional anesthesia may decrease complication rates and resource utilization in shoulder arthroplasty patients. METHODS: We examined administrative data from 588 US hospitals from 2010 to 2015. Logistic regression was used to examine the relationship between type of anesthesia and perioperative complications. RESULTS: Among patients who underwent shoulder arthroplasty, 79.1% (53,243) had general anesthesia alone, 17.8% (12,011) had general anesthesia and a nerve block, and 3.1% (2062) had a nerve block alone. Overall, the complication rate was 13.3% and 30-day mortality was 1.2 per 1000 (95% CI 0.9, 1.4). In adjusted analyses, patients who had general anesthesia alone (compared to general anesthesia and nerve block) had a 16% increase in all cause infectious complications (OR 1.16, 95% CI: 1.03, 1.31) and were 2.6 times more likely to develop pulmonary complications (OR 2.6, 95% CI: 1.14, 5.78). General anesthesia alone (relative to either block only or general anesthesia and block) was associated with substantial increases in the likelihood of blood transfusions, intensive care unit transfers, and prolonged length of stay. CONCLUSION: Patients receiving regional anesthesia for shoulder arthroplasty may have a reduction in perioperative complications, the need for intensive care unit transfers, blood transfusions, and prolonged hospital stays.

Adductor canal blocks: changing practice patterns and associated quality profile.

BACKGROUND: Femoral nerve blocks have been the gold standard approach for post-operative analgesia following total knee arthroplasty; however, the adductor canal block has recently gained popularity due to less block-induced motor weakness. The primary aim of this time-series analysis was to identify whether regional anesthesia practice changes have occurred for total knee arthroplasty. Our secondary aim was to assess for possible associated changes in safety and quality. METHODS: Using a 20-member clinical registry, we examined the practice patterns and safety around the performance of adductor canal blocks for all total knee arthroplasties between 18 July 2011 to 9 October 2015. To obtain more information about changes in quality associated with this practice transition, we analyzed clinical outcomes data surrounding all primary total knee arthroplasties from the largest contributing institution. RESULTS: A total of 6921 blocks were performed for 4822 primary and revision total knee arthroplasties (TKAs). Across the registry, adductor canal block utilization for TKA increased. This was not associated with any increase in immediate or recovery room-related complications. When analyzing unilateral primary TKAs from the largest surgical volume center (n = 766), there were no statistically significant changes in numeric rating scale scores (5.4 to 4.6, P value = 0.004), length of stay (3.0 to 2.8 days, P value = 0.3), or 30-day hospital re-evaluations for pain (2.8-4.9%, P value = 0.1). CONCLUSION: There was a large increase in the utilization of adductor canal blockade for TKAs among participating registry members. This change in practice was not associated with significant changes in safety or quality.

Fluoroscopy-assisted epidural catheter placement: an exploratory analysis of 303 pre-operative epidurograms.

BACKGROUND: Epidural catheters that are placed for post-operative analgesia have a significant failure rate in the first 24 hours. Beginning in 2011, we have used fluoroscopic guidance to place all non-obstetrical epidural catheters. In this retrospective analysis, we hypothesized that the characteristics of dye distribution on an epidurogram obtained immediately after catheter placement would predict clinical catheter function after surgery. METHODS: The epidurograms and medical records of 303 consecutive patients who had epidural catheters placed for post-operative analgesia were reviewed. We extracted data on epidural dye distribution on the epidurograms and compared these results to the clinical function of the epidural catheters assessed on post-operative day 1 (POD1). RESULTS: The three-dimensional pattern of epidural dye distribution (cephalad-caudad, right-left, anterior-posterior) had significant correlations with clinical function of an epidural catheter after surgery. Increased cephalad-caudad and anterior dye spread both correlated with decreased epidural solution infusion rates on POD1, whereas right- or left-sided dye distribution correlated with unilateral sensory deficits. A higher catheter placement on the neuraxis correlated with lower pain scores after thoracic surgery. CONCLUSIONS: An epidurogram obtained immediately after epidural catheter placement may have clinical utility for predicting clinical function of the catheter after surgery.

Ultrasound-guided interscalene blocks: understanding where to inject the local anaesthetic.

Although ultrasound-guided regional anaesthesia has gained in popularity, few data exist describing the optimal location(s) to inject local anaesthetic. Our objective was to compare, for interscalene blocks, the effectiveness of an injection between the middle scalene muscle and brachial plexus sheath (peri-plexus) with an injection within the brachial plexus sheath (intra-plexus). We enrolled 170 patients undergoing shoulder surgery with general anaesthesia and interscalene block in this randomised, controlled trial. Our primary outcome variable was loss of shoulder abduction. Block quality was also measured and defined by an evaluation of onset time, sensory and motor loss and duration. There was no difference between the two groups in block onset times or block quality. After adjusting for sex, age and volume injected, intra-plexus blocks lasted a mean of 2.6 h (16%) longer (95% CI 0.25-5.01, p=0.03) than peri-plexus blocks.

Evaluation of pre-procedure ultrasound examination as a screening tool for difficult spinal anaesthesia*.

We performed a pre-procedure ultrasound examination of the spine on 60 patients undergoing lower extremity orthopaedic surgery under spinal anaesthesia. We hypothesised that the inability to identify the posterior longitudinal ligament or vertebral body easily with ultrasound would be associated with difficulty placing a spinal anaesthetic. Clinicians blinded to the ultrasound scan performed the injections using the traditional landmark technique. The spinal procedure was videotaped and subsequently reviewed by independent investigators. We defined procedure difficulty by total procedure time (> 400 s) and number of needle passes (≥ 10) required to achieve return of cerebrospinal fluid, or abandonment of the procedure due to unsuccessful dural puncture. When images of the posterior longitudinal ligament were poor (low score group), the mean (SD) number of passes was 21.2 (30.6), compared with 4.8 (7.5) with good ultrasound images (high score group) (p < 0.01). The mean (SD) time for placement was 420 (300) s in the low score group vs 176 (176) s in the high score group (p < 0.01). You can respond to this article at http://www.anaesthesiacorrespondence.com.

Electron microscopy evaluation of block needle-related trauma to the tibial nerve.

BACKGROUND: Direct puncture by a needle is a risk factor for nerve damage. This investigation used scanning electron microscopy (SEM) to attempt to visualize the damage caused by different needles. METHOD: A 15 cm section of the tibial nerve was removed from the ankle of a patient undergoing below-the-knee amputation. The nerve specimen was punctured perpendicular to the fibers once by each of four needles: an insulated 22 G short-beveled (30 degrees), a 25 G long-beveled Quincke spinal needle, an 18 G Tuohy, and a 25 G Whitacre pencil point. The distal and proximal ends on either side of the needles were marked and the nerve was sectioned into 0.5 cm pieces. Each sample was preserved and then prepared for SEM. The needle tract was observed for evidence of mechanical damage at magnifications between x 47 and x 102 using SEM. RESULTS: The epineurium, perineurium, fascicles, endoneurium, and vessels were identified in each sample. In both the short-beveled and the Whitacre samples, all fascicles along with the surrounding perineurium were intact. In both the Tuohy and the Quincke samples, obvious transection of fascicles and disruption of the perineurium were observed. CONCLUSIONS: This investigation suggests that both the Tuohy and the Quincke needles may be more likely to cause trauma to the tibial nerve than either the short-beveled or the Whitacre needles.

Regional anesthesia meets ultrasound: a specialty in transition.

Despite its well-known benefits, regional anesthesia has not attained the stature, simplicity, and safety of general anesthesia. Many of the challenges and clinical failures of regional anesthetic techniques can be attributed to fact that neurovascular anatomy is highly variable. Furthermore, current nerve localization techniques provide little or no information regarding the anatomical spread local anesthesia. Recently, ultrasound technology has been utilized by anesthesiologists in an attempt to minimize many of the drawbacks of traditional nerve block techniques. This review article will update the reader on the current status of ultrasound-guided regional anesthesia, provide an evidence-based context, and supply key facts regarding ultrasound physics. In the process, we will also highlight several possible limitations of ultrasound techniques including learning curve issues, costs, and artifact generation.

Ultrasound guidance improves the success rate of a perivascular axillary plexus block.

BACKGROUND: Traditional approaches to performing brachial plexus blocks via the axillary approach have varying success rates. The main objective of this study was to evaluate if a specific technique of ultrasound guidance could improve the success of axillary blocks in comparison to a two injection transarterial technique. METHODS: Fifty-six ASA physical status I-III patients presenting for elective hand surgery were prospectively randomized to receive an axillary block performed by either a transarterial technique (Group TA) or an ultrasound-guided perivascular approach (Group US). Both groups received a total of 30 ml of 1.5% lidocaine (225 mg) with 5 microg/ml epinephrine. Patients were then evaluated for block onset in specific nerve distributions and whether or not the block acted as a surgical anesthetic. RESULTS: Group TA sustained more failures defined as conversion to general anesthesia or the inability to localize the artery [Group TA eight patients (29%) vs. Group US in which 0 patients required conversion to general anesthesia (0%) P < 0.01]. Group US demonstrated a reduction in performance times vs. Group TA (7.9 +/- 3.9 min vs. 11.1 +/- 5.7 min, P < 0.05). By 30 min post-injection, there were no significant differences between groups TA and US in terms of the proportion of patients demonstrating a complete motor or sensory loss. CONCLUSION: Ultrasonographic guidance improves the overall success rate of axillary blocks in comparison to a transarterial technique.