Combined caudal retrocostal and lateral ultrasound-guided approach for transversus abdominis plane injection: A descriptive pilot study in pig cadavers.

Transversus abdominis plane (TAP) block is a regional anesthetic technique used to desensitize the abdominal wall in several species. This study aimed to describe the anatomical characteristics of the abdominal wall and to identify a feasible approach for an US-guided TAP injection that would result in adequate staining of the relevant nerves in the abdominal wall in pig cadavers. Fresh cadavers from five Landrace pigs (age, 12 weeks; body weight, 35.5 ± 1.6 kg) were used. One pig (n = 1) was anatomically dissected, and four pigs (n = 4; i.e., 8 hemiabdomens) were used for TAP injections and evaluation of dye spread. The volume of 0.3 mL/kg/injection point of methylene blue was injected bilaterally. In the caudal retrocostal approach, the injection was performed ventral to the most caudal part of the costal arch. In the lateral approach, the injection was performed between the last rib and iliac crest. A needle was inserted in plane for the caudal retrocostal and the lateral approach caudocranially and craniocaudally, respectively. Successful staining was defined as presence of dye on the nerve for a length of >1 cm in its entire circumference. The TAP was found between different muscle layers in the described anatomical regions. In the caudal retrocostal approach the TAP was found between the external abdominal oblique and transversus abdominis muscle bellies. In the lateral approach the TAP was found between the internal abdominal oblique and transversus abdominis muscles. The approach combining lateral and caudal retrocostal injections at the studied volume stained a median of 5 (3-6) target nerves from the fourth-last thoracic nerve to L2 (six nerves). Combined caudal retrocostal and lateral TAP injections of 0.3 mL/kg/injection point, resulted in staining of target nerve branches which supply the periumbilical and caudal abdominal wall in pig cadavers.

Ultrasonographic anatomy of the long thoracic nerve: A reappraisal using high frequency (24-MHz) probe.

PURPOSE: The purpose of this study was to analyze the potential of ultrasound with a high frequency probe (24-MHz) in the assessment of the long thoracic nerve (LTN) and describe ultrasonographic landmarks that can be used for standardization. MATERIAL AND METHODS: Ultrasonography analysis of the LTN was done on 2 LTNs in a cadaver specimen and then on 30 LTNs in 15 healthy volunteers (12 men, 3 women; mean age, 28.8±3.8 [SD] years; age range: 24-39 years) by two independent radiologists (R1 and R2) using a 24-MHz probe. Interrater agreement was assessed using Kappa test (K) and intraclass correlation coefficient (ICC). RESULTS: In the cadaver, dissection confirmed that the India ink was injected near the LTN in the middle scalene muscle. In volunteers, visibility of the LTN above the clavicle was highly reproducible for the branches arising from C5 (R1: 87% [26/30]; R2: 90% [27/30]; K=0.83) and from C6 (R1: 100% [30/30]; R2: 97% [29/30]; K=0.94). Where the nerve emerged from the middle scalene muscle, the mean diameter was 0.85±0.24 (SD) mm (range: 0.4-1.6mm) for R1 and 0.9±0.23 (SD) mm (range: 0.4-1.7mm) for R2 (ICC: 0.96; 95% CI: 0.92-0.98%). Along the thoracic wall, where LTN run along the lateral thoracic artery, the mean diameter was 0.83±0.19 (SD) mm (range: 0.5-1.27mm) for R1 and 0.89±0.21 (SD) mm (range: 0.6-1.2mm) for R2 (ICC: 0.86; 95% CI: 0.72-0.93%). CONCLUSION: The LTN can be analyzed with ultrasound using high-frequency probe by using the C5 and C6 roots, the middle scalene muscle above the clavicle and the lateral thoracic artery on the chest wall as landmarks.

Shrug radiographs for the diagnosis of long thoracic nerve palsy in traumatic brachial plexus injury.

BACKGROUND: Preoperative diagnosis of long thoracic nerve (LTN) palsy is important for shoulder reconstruction after a traumatic brachial plexus injury (BPI). In the present study, we developed an objective diagnostic method for LTN palsy for patients with traumatic BPI. METHODS: This is a retrospective review of 56 patients with traumatic BPI who had been receiving treatment at a single institution for over 8 years. The patients were divided into 2 groups: an LTN palsy group (n = 30) and a no palsy control group (n = 26). The LTN palsy group had 21 different palsy types with 4 and 5 C5-7 and C5-8, whereas the no palsy group had 18 different palsy types with 5 and 3 C5-6 and C5-8, respectively. Preoperative plain anteroposterior radiographs were taken in shoulder adduction and shrug positions. Scapulothoracic (ST) upward rotation and clavicle lateral (CL) rotation angles were measured on X-rays. The differences between the adduction and shrug positions for the respective angles were calculated and defined as ΦST and ΦCL, respectively. The differences in the ΦST and ΦCL values due to the presence or absence of LTN palsy were examined, the cutoff values of ΦST and ΦCL for the diagnosis of LTN palsy were determined, and further sensitivity and specificity were calculated. RESULTS: Both ΦST and ΦCL were significantly decreased in the LTN palsy group compared with the no palsy control group. The sensitivity and specificity for LTN palsy were 0.833 and 1.000 for ΦST and 0.833 and 0.840 for ΦCL, respectively, when the cutoff value was set as ΦST = 15° and ΦCL ≤ 24°. CONCLUSION: Dynamic shrug radiographs provide a useful objective diagnosis of LTN palsy after traumatic BPI.

Identification of long thoracic nerve on high-resolution 3T MRI.

OBJECTIVE: Long thoracic neuropathy results in serratus anterior muscle denervation and presents with scapular winging. Previously published studies have been unable to identify the long thoracic nerve on MRI; instead, secondary imaging features of serratus anterior muscle denervation are used to infer nerve injury. Our study's purpose was to evaluate the ability of high-resolution MRI to depict the long thoracic nerve. MATERIALS AND METHODS: In this HIPAA-compliant, IRB-approved retrospective study, two musculoskeletal radiologists reviewed the brachial plexus MRI exans of 24 subjects performed for clinical suspicion of long thoracic neuropathy. The radiologists evaluated whether the long thoracic nerve could be identified and for the presence of serratus anterior denervation; when the nerve was seen, assessment for nerve enlargement, signal hyperintensity, and morphologic change was performed. Inter-observer reliability was estimated with Cohen's kappa (κ). Clinical presentation and electromyogram (EMG) were then reviewed. RESULTS: The long thoracic nerve was identified in 18 cases (75%), with high inter-observer reliability for nerve visualization. Kappa values of 1.0, 0.9, 1.0, and 0.9 were obtained for identification of the LTN on coronal sequences of the brachial plexus, identification of the LTN on proximal and mid segments of the nerve on oblique sagittal sequences, and identification of the distal segment of the LTN on axial sequences through the chest, respectively. The nerve was identified in 91% of patients with positive EMG findings for a long thoracic neuropathy. In patients with EMG features of long thoracic neuropathy, 70% had corresponding abnormal MRI features. When denervation edema was present, the nerve was identified 86% of the time. CONCLUSION: High-resolution MRI can be used to visualize segments of the long thoracic nerve.

Cryoneurolysis in Patients with Dorsal Neuropathic Pain Secondary to Tumor Invasion.

PURPOSE: To evaluate the safety and efficacy of cryoneurolysis (CNL) in patients with refractory thoracic neuropathic pain related to tumor invasion. MATERIALS AND METHODS: Between January 2013 and May 2017, this single-center and retrospective study reviewed 27 computed tomography-guided CNLs performed on 26 patients for refractory thoracic neuropathic pain related to tumor invasion. Patients with cognitive impairment were excluded. Pain levels were recorded on a visual analog scale (VAS) before the procedure, on days 1, 7, 14, 28 and at each subsequent follow-up appointment. CNL was clinically successful if the postprocedural VAS decreased by 3 points or more. To determine the duration of clinical success, the end of pain relief was defined as either an increased VAS of 2 or more points, the introduction of a new analgesic treatment, a death with controlled pain, or for lost to follow-up patients, the latest follow-up appointment date with controlled pain. RESULTS: Technical success rate was 96.7% and clinical success rate was 100%. Mean preprocedural pain score was 6.4 ± 1.7 and decreased to 2.4 ± 2.4 at day 1; 1.8 ± 1.7 at day 7 (P < .001); 3.3 ± 2.5 at day 14; 3.4 ± 2.6 at day 28 (P < .05). The median duration of pain relief was 45 days (range 14-70). Two minor complications occurred. CONCLUSIONS: Cryoneurolysis is a safe procedure that significantly decreased pain scores in patients with thoracic neuropathic pain related to tumor invasion, with a median duration of clinical success of 45 days.

Multiphasic presentation of neuralgic amyotrophy associated with hepatitis E virus infection.

BACKGROUND: The aim of this study was to further characterize the clinical phenotype of hepatitis E virus (HEV)-associated neuralgic amyotrophy (NA). METHODS: Three patients with HEV-associated NA underwent clinical, electrodiagnostic, and ultrasound assessment. RESULTS: In all patients, symptoms developed in several phases within a time span of 4-6 weeks, with three or more nerves involved. Symptoms were bilateral in two. In two patients, nerves of the trunk and the lower limb were affected as well. In one patient, three bouts occurred, each heralded by an increase in pain. In the other two, pain subsided quickly and nerve damage developed in two phases. Segmental enlargement with or without hourglass-like constrictions of the nerves was demonstrated by ultrasound in all. CONCLUSIONS: The multiphasic presentation, together with the extensive multi-nerve involvement, may reflect a severe and protracted inflammation of the nerves in HEV-associated NA.

Schwannoma of the long thoracic nerve in the left axilla: a case report.

Schwannoma, which is also known as neurilemmoma, is a type of tumor that arises from the peripheral nerve sheaths. Cases of schwannomas located in different regions have been reported. Some schwannomas present as asymptomatic masses, while others cause discomfort, such as pain and numbness. Magnetic resonance imaging (MRI) is a valuable diagnostic tool. A 23-year-old woman presented to our hospital with a mass in the left axilla that was misdiagnosed as mammae erraticae. The patient also considered the condition to be mammae erraticae for approximately 14 months because of a lack of symptoms. MRI was recommended by a surgeon from the galactophore department. A giant schwannoma was found. The mass was surgically excised, while preserving the continuity of the long thoracic nerve. Routine histopathological analysis confirmed the presence of a benign schwannoma. Schwannomas located in the axilla are rare and may be easily misdiagnosed as mammae erraticae or enlarged lymph nodes. Early investigation is necessary to make the diagnosis, and surgical excision is usually curative.

PECS, serratus plane, erector spinae, and paravertebral blocks: A comprehensive review.

Thoracic planar blocks represent a novel and rapidly expanding facet of regional anesthesia. These recently described techniques represent the potential for excellent analgesia, enhanced technical safety profiles, and reduced physiological side effects versus traditional techniques in thoracic anesthesia. Regional techniques, particularly those described in this review, have potential implications for mitigation of surgical pathophysiological neurohumoral changes. In the present investigation, we describe the history, common indications, technique, and limitations of pectoral nerves (PECS), serratus plane, erector spinae plane, and thoracic paravertebral plane blocks. In summary, these techniques provide excellent analgesia and merit consideration in thoracic surgery.

Sonoanatomy revisited: the long thoracic nerve.

The long thoracic nerve (LTN) arises from the C5, C6 and C7 roots and innervates the serratus anterior muscle. Scapular winging is the landmark manifestation of LTN neuropathy and may develop after an accidental injury during selective cervical nerve root or inter-scalene brachial plexus blocks. Although its sonoanatomy has been described in the previous literature, how to gradually identify the entire nerve course has rarely been discussed. In this regard, the present paper aims to elaborate the scanning method of the LTN from its origin to its distal segment.

Comparison of the effects of modified pectoral nerve block and erector spinae plane block on postoperative opioid consumption and pain scores of patients after radical mastectomy surgery: A prospective, randomized, controlled trial.

STUDY OBJECTIVE: Breast cancer is the most common malignancy of women all over the world. In this study, we compared the effects of ultrasound-guided modified pectoral nerve (PECS) block and erector spinae plane (ESP) block on postoperative opioid consumption, pain scores, and intraoperative fentanyl need of patients undergoing unilateral modified radical mastectomy surgery. DESIGN: Single-blinded, prospective, randomized, efficacy study. SETTING: Tertiary university hospital, postoperative recovery room and surgical ward. PATIENTS: Forty patients (ASA I-II) were allocated to two groups. After exclusion, 38 patients were included in the final analysis (18 patients in the PECS groups and 20 in the ESP group). INTERVENTIONS: Modified pectoral nerve block was performed in the PECS group and erector spinae plane block was performed in the ESP group. MEASUREMENTS: Postoperative tramadol consumption and pain scores were compared between the groups. Also, intraoperative fentanyl need was measured. MAIN RESULTS: Postoperative tramadol consumption was 132.78 ±â€¯22.44 mg in PECS group and 196 ±â€¯27.03 mg in ESP group (p = 0.001). NRS scores at the 15th and 30th min were similar between the groups. However, median NRS scores were significantly lower in PECS group at the postoperative 60th min, 120th min, 12th hour and 24th hour (p = 0.024, p = 0.018, p = 0.021 and p = 0.011 respectively). Intraoperative fentanyl need was 75 mg in PECS group and 87.5 mg in ESP group. The difference was not statistically significant (p = 0.263). CONCLUSION: Modified PECS block reduced postoperative tramadol consumption and pain scores more effectively than ESP block after radical mastectomy surgery.

Comparison of the Efficacy of Ultrasound-Guided Serratus Anterior Plane Block, Pectoral Nerves II Block, and Intercostal Nerve Block for the Management of Postoperative Thoracotomy Pain After Pediatric Cardiac Surgery.

OBJECTIVE: The aim of this study was to compare the relative efficacy of ultrasound-guided serratus anterior plane block (SAPB), pectoral nerves (Pecs) II block, and intercostal nerve block (ICNB) for the management of post-thoracotomy pain in pediatric cardiac surgery. DESIGN: A prospective, randomized, single-blind, comparative study. SETTING: Single-institution tertiary referral cardiac center. PARTICIPANTS: The study comprised 108 children with congenital heart disease requiring surgery through a thoracotomy. INTERVENTIONS: Children were allocated randomly to 1 of the 3 groups: SAPB, Pecs II, or ICNB. All participants received 3 mg/kg of 0.2% ropivacaine for ultrasound-guided block after induction of anesthesia. Postoperatively, intravenous paracetamol was used for multimodal and fentanyl was used for rescue analgesia. MEASUREMENTS AND MAIN RESULTS: A modified objective pain score (MOPS) was evaluated at 1, 2, 4, 6, 8, 10, and 12 hours post-extubation. The early mean MOPS at 1, 2, and 4 hours was similar in the 3 groups. The late mean MOPS was significantly lower in the SAPB group compared with that of the ICNB group (p < 0.001). The Pecs II group also had a lower MOPS compared with the ICNB group at 6, 8, and 10 hours (p < 0.001), but the MOPS was comparable at hour 12 (p = 0.301). The requirement for rescue fentanyl was significantly higher in ICNB group in contrast to the SAPB and Pecs II groups. CONCLUSION: SAPB and Pecs II fascial plane blocks are equally efficacious in post-thoracotomy pain management compared with ICNB, but they have the additional benefit of being longer lasting and are as easily performed as the traditional ICNB.

Unilateral winged scapula: Clinical and electrodiagnostic experience with 128 cases, with special attention to long thoracic nerve palsy.

INTRODUCTION: In this study we report a large series of patients with unilateral winged scapula (WS), with special attention to long thoracic nerve (LTN) palsy. METHODS: Clinical and electrodiagnostic data were collected from 128 patients over a 25-year period. RESULTS: Causes of unilateral WS were LTN palsy (n = 70), spinal accessory nerve (SAN) palsy (n = 39), both LTN and SAN palsy (n = 5), facioscapulohumeral dystrophy (FSH) (n = 5), orthopedic causes (n = 11), voluntary WS (n = 6), and no definite cause (n = 2). LTN palsy was related to neuralgic amyotrophy (NA) in 61 patients and involved the right side in 62 patients. DISCUSSION: Clinical data allow for identifying 2 main clinical patterns for LTN and SAN palsy. Electrodiagnostic examination should consider bilateral nerve conduction studies of the LTN and SAN, and needle electromyography of their target muscles. LTN palsy is the most frequent cause of unilateral WS and is usually related to NA. Voluntary WS and FSH must be considered in young patients. Muscle Nerve 57: 913-920, 2018.

Pectoral Fascial (PECS) I and II Blocks as Rescue Analgesia in a Patient Undergoing Minimally Invasive Cardiac Surgery.

INTRODUCTION: Patients undergoing minimally invasive cardiac surgery have the potential for significant pain from the thoracotomy site. We report the successful use of pectoral nerve block types I and II (Pecs I and II) as rescue analgesia in a patient undergoing minimally invasive mitral valve repair. CASE REPORT: In this case, a 78-year-old man, with no history of chronic pain, underwent mitral valve repair via right anterior thoracotomy for severe mitral regurgitation. After extubation, he complained of 10/10 pain at the incision site that was minimally responsive to intravenous opioids. He required supplemental oxygen because of poor pulmonary mechanics, with shallow breathing and splinting due to pain, and subsequent intensive care unit readmission. Ultrasound-guided Pecs I and II blocks were performed on the right side with 30 mL of 0.2% ropivacaine with 1:400,000 epinephrine. The blocks resulted in near-complete chest wall analgesia and improved pulmonary mechanics for approximately 24 hours. After the single-injection blocks regressed, a second set of blocks was performed with 266 mg of liposomal bupivacaine mixed with bupivacaine. This second set of blocks provided extended analgesia for an additional 48 hours. The patient was weaned rapidly from supplemental oxygen after the blocks because of improved analgesia. CONCLUSIONS: Pectoral nerve blocks have been described in the setting of breast surgery to provide chest wall analgesia. We report the first successful use of Pecs blocks to provide effective chest wall analgesia for a patient undergoing minimally invasive cardiac surgery with thoracotomy. We believe that these blocks may provide an important nonopioid option for the management of pain during recovery from minimally invasive cardiac surgery.