A Case of Hospitalization After Pre-operative Interscalene Nerve Block in an Ambulatory Surgery Center.

Interscalene nerve block (ISB) is an effective and low-risk local anesthetic (LA) procedure that is commonly employed for shoulder surgery. While phrenic nerve involvement occurs to some degree in every ISB procedure, the incidence of hypoxemia and other clinical signs of diaphragmatic disruption is much lower. This is a case of a 36-year-old female with no underlying respiratory disease who developed hypoxemia requiring a night of observation following an ISB for a rotator cuff repair procedure in an ambulatory surgical center. Her hypoxemia was easily treated with supplemental oxygen and she made a full recovery by the next day. The use of ultrasound guidance, reduced LA volume, less potent medication, sterile fluid for optimal visualization, and extrafascial administration should be considered for all patients receiving an ISB to prevent respiratory complications.

Bilateral Phrenic Nerve Palsy Associated With Neuralgic Amyotrophy.

Neuralgic amyotrophy (NA) is a multifocal inflammatory neuropathy accompanied by acute pain and muscle atrophy. NA commonly affects the upper extremities, but rarely affects the phrenic nerve. Here, we report a male with neck pain, orthopnea, difficulty sleeping in the supine position, and inability to slurp. His saturated oxygen level decreased from 97% to 86% in the supine position. His right shoulder showed muscle atrophy. Chest X-ray examination in the supine position and a nerve conduction study showed phrenic palsy. We diagnosed it as bilateral phrenic nerve palsy associated with NA. NA sometimes causes phrenic nerve palsy and may cause slurping difficulty.

Unilateral Phrenic Nerve Palsy as a Presentation of Diabetes Mellitus: A Rare Case Report.

Diabetes mellitus is one of the most debilitating diseases, diabetic neuropathy happens to be the most common and perhaps the most serious complication of diabetes mellitus, often leading to morbidity and mortality. A 60 year old female presented with disorientation, history of vomiting, shortness of breath, respiratory failure initially. Blood reports revealed that she was positive for ketone bodies with elevated HbA1c and general random blood sugar. Chest radiogram revealed atelectasis of the right lung with prominent involvement of right middle and lower lobes. High-resolution computed tomography of chest confirmed the findings and unilateral diaphragmatic paralysis due to phrenic nerve neuropathy due to undetected type 2 diabetes was diagnosed. Although phrenic nerve paralysis is a rare occurrence with diabetes, the possibility shouldn't be overlooked as a presentation of diabetes mellitus.

Erector Spinae Plane Block as the Phrenic Nerve Sparing Anaesthetic Technique for Shoulder Arthroplasty.

The utilization of the brachial plexus block has become commonplace in shoulder replacement surgery and the management of postoperative pain. Nonetheless, this technique carries risks, including the occurrence of phrenic nerve palsy and subsequent postoperative dyspnea. In light of these concerns, the erector spinae plane block emerges as a safe, simple, and effective alternative for shoulder surgery with reduced risk of phrenic nerve palsy and potential motor sparing in the affected limb. This research endeavors to elucidate the analgesic application of erector spinae plane block (ESPB) through the presentation and analysis of two cases involving reverse shoulder arthroplasty.

Peri-operative Hemi-diaphragmatic Variations After Brachial Plexus Block Above the Clavicle: A Prospective Observational Study of the Contralateral Side.

OBJECTIVE: Hemi-diaphragm palsy after brachial plexus block above the clavicle (BPBAC) occurs frequently, but few patients develop post-operative pulmonary complications (PPC). We hypothesized that contralateral hemidiaphragm function increases after BPBAC. This contralateral function preserves global diaphragmatic function, avoiding PPC in the case of ipsilateral hemi-diaphragm palsy. METHODS: This prospective observational cohort study included 64 adult patients undergoing shoulder surgery with planned BPBAC (interscalene brachial plexus block and supraclavicular block). The Thickening Fraction (TF) was measured by ultrasound in both hemi-diaphragms, ipsilateral (TF ipsilateral) and contralateral (TFcontralateral) to the BPBAC, before and after the surgery. TFglobal is the sum of TFipsilateral and TFcontralateral. PPC were defined as occurrences of dyspnea, tachypnea, SpO2 <90% or SpO2/FiO2 <315. RESULTS: TFcontralateral increased significantly (an average of 40%) after BPBAC (p = 0.001), and TFipsilateral decreased (an average of 72%). After BPBAC, 86% of patients had a decreased TFipsilateral and 59% of patients an increased TFcontralateral at post-operatively. Only 17% of patients have PPC. CONCLUSION: After BPBAC, global diaphragm function decreases because of ipsilateral hemi-diaphragm reduction, but less than expected because of increased contralateral hemi-diaphragm function. As a part of diaphragm function, contralateral hemi-diaphragm function must be checked.

Single port thoracoscopic diaphragm plication: A novel treatment approach to bilateral phrenic nerve palsy and diaphragm paralysis.

INTRODUCTION AND IMPORTANCE: The diaphragm is the primary muscle of respiration. Bilateral paralysis of the diaphragm due to phrenic nerve palsy causes severe dyspnoea and is life threatening. Diaphragmatic Plication has shown great promise in treating diaphragm paralysis and has evolved as operative treatment from an open thoracotomy to multiport and robotic video assisted thoracoscopic surgery. CASE PRESENTATION: Here we present a case of idiopathic bilateral diaphragm paralysis resulting significant deterioration in lung function tests, supplemental oxygen, and ventilator dependence. The patient was treated with a 2-stage operative plication of each hemidiaphragm through a 2.5 cm single incision thoracoscopic technique, which resulted in normalization of lung function tests, elimination of oxygen dependence and negligible analgesia requirements. CASE DISCUSSION: This is the first case reported in the literature of a single port VATS plication of the diaphragm for the treatment of bilateral phrenic nerve palsy. Surgery, specifically diaphragm plication, is indicated for patients with significant symptoms and persistent paralysis. Video-assisted thoracoscopic surgery (VATS) has evolved from open operations to smaller incisions, offering improved lung function, postoperative pain, hospital stay, morbidity, and mortality. CONCLUSION: Single port diaphragmatic plication is a novel approach to the treatment of bilateral phrenic nerve palsy. We make the case for indication of the technique for treatment of diaphragmatic paralysis.

The diagnostic utility of inspiratory-expiratory radiography for the assessment of phrenic nerve palsy associated with brachial plexus injury.

BACKGROUND: The phrenic nerve is commonly injured with trauma to the brachial plexus. Hemi-diaphragmatic paralysis may be well-compensated in healthy individuals at rest but can be associated with persistent exercise intolerance in some patients. This study aims to determine the diagnostic value of inspiratory-expiratory chest radiography compared to intraoperative stimulation of the phrenic nerve for assessing phrenic nerve injury associated with brachial plexus injury. METHODS: Over a 21-year period, the diagnostic utility of three-view inspiratory-expiratory chest radiography for identification of phrenic nerve injury was determined by comparison to intraoperative phrenic nerve stimulation. Multivariate regression analysis was used to identify independent predictors of phrenic nerve injury and having an incorrect radiographic diagnosis. RESULTS: A total of 237 patients with inspiratory-expiratory chest radiography underwent intraoperative testing of phrenic nerve function. Phrenic nerve injury was present in approximately one-fourth of cases. Preoperative chest radiography had a sensitivity of 56%, specificity of 93%, positive predictive negative of 75%, and negative predictive value of 86% for identification of a phrenic nerve palsy. Only C5 avulsion was found to be a predictor of having an incorrect diagnosis of phrenic nerve injury on radiography. CONCLUSION: While inspiratory-expiratory chest radiography has good specificity for detecting phrenic nerve injuries, a high number of false negatives suggest that it should not be relied upon for routine screening of dysfunction after traumatic brachial plexus injury. This is likely multifactorial and relates to variation in diaphragm shape and position, as well as limitations regarding static image interpretation of a dynamic process.

Cryoablation for atrial tachycardia with cycle length variability originating from the vicinity of the sinus node.

This case is about atrial tachycardia with cycle length variability originating from the vicinity of the sinus node and diagnostic pacing maneuvers to assess the tachycardia circuit were not achieved. Activation mapping revealed that the origin of atrial tachycardia was 15 mm away from the sinus node and the phrenic nerve was captured by pacing at the posterior portion of atrial tachycardia. A multipolar catheter was placed in the right brachiocephalic vein to capture the right phrenic nerve by pacing. The absence of phrenic nerve palsy was confirmed by palpation of constant diaphragmatic movement. The cryoablation could be safely and efficiently performed without ablation-induced injury of sinus node and phrenic nerve palsy by confirming constant diaphragmatic movement. The efficacy of cryoablation in the vicinity of the conduction system and phrenic nerve will be increasingly confirmed in the future. Learning Objective: Cryoablation for atrial tachycardia might be more safe and effective in terms of ablation-induced injury of conduction system and phrenic nerve palsy compared with conventional radiofrequency ablation when diagnostic pacing maneuvers are not able to estimate the circuit due to variability of tachycardia cycle length.

Optimal prevention method of phrenic nerve injury in superior vena cava isolation: efficacy of high-power, short-duration radiofrequency energy application on the risk points.

BACKGROUND OR PURPOSE: Superior vena cava isolation (SVCI) is widely performed adjunctively to atrial fibrillation (AF) ablation. Right phrenic nerve injury (PNI) is a complication of this procedure. The purpose of the study is to determine the optimal PNI prevention method in SVCI. METHODS: A total of 1656 patients who underwent SVCI between 2009 and 2022 were retrospectively examined. PNI was diagnosed based on the diaphragm position and movement in the upright position on chest radiographs before and after SVCI. RESULTS: With the introduction of various PN monitoring systems over the years, the incidence of SVCI-associated PNI has decreased. However, complete PNI avoidance has not been achieved. PNI incidence according to fluoroscopy-guided PN monitoring, high-output pace-guided, compound motor action potential-guided, and 3-dimensional electro-anatomical mapping (EAM) systems was 8.1% (38/467), 2.7% (13/476), 2.4% (4/130), and 2.8% (11/389), respectively. However, a high-power, short-duration (50 W/7 s) radiofrequency (RF) energy application only on PNI risk points tagged by a 3-dimensional EAM system completely avoids PNI (0%; 0 /160 since April 2021). PNI showed no symptoms and recovered within an average of 188 days post-SVCI, except for a few patients who required > 1 year. CONCLUSIONS: Although PNI incidence decreased annually with the introduction of various monitoring systems, these monitoring systems did not prevent PNI completely. Most notably, the delivery of a high-power, short-duration RF energy only on risk points tagged by EAM prevented PNI completely. PNI recovered in all patients. The application of higher-power, shorter-duration RF energy on risk points tagged by EAM appears to be an optimal PNI prevention maneuver.

Asymptomatic unilateral phrenic nerve palsy after bortezomib treatment in a newly diagnosed multiple myeloma patient.

INTRODUCTION: Bortezomib is the first chemotherapeutic agent of proteosome inhibitor class that can be used in newly diagnosed and relapsed/refractory multiple myeloma. It is well known that bortezomib has side effects such as peripheral sensory, motor, or autonomic neuropathy. In this paper, we will present our patient who developed unilateral phrenic nerve palsy as an autonomic neuropathy after six cycles of subcutaneous bortezomib treatment. This case differs from other cases in that our patient was asymptomatic. CASE REPORT: A 57-year-old male patient was admitted with back pain and gait disturbances. In the thorax computed tomography, a soft tissue mass causing compression on the spinal canal was observed in the T12 vertebra. Bone biopsy pathology report resulted in diffuse plasma cell infiltration. The patient was diagnosed with stage ISS-3, IgG kappa type multiple myeloma. MANAGEMENT AND OUTCOME: Subcutaneous bortezomib 1 × 2.2 mg (Days 1-4-8-11) + intravenous cyclophosphamide 1000 mg (Day 1) + intravenous dexamethasone 40 mg (Days 1-2-3-4) (VCD chemotherapy protocol) was started. Totally six cycles of VCD were administered. While the patient did not have any respiratory symptoms, an elevation consistent with phrenic nerve palsy was observed in the left hemidiaphragm in the thorax computed tomography that was taken during the preparation for autologous hematopoietic stem cell transplantation. DISCUSSION: Bortezomib is a frequently used chemotherapeutic agent in patients with multiple myeloma and care should be taken in terms of the risk of developing phrenic nerve palsy in patients. There are cases of autonomic neuropathy developing after bortezomib treatment.

3D mapping of phrenic nerve course for radiofrequency pulmonary vein isolation.

INTRODUCTION: Phrenic nerve (PN) injury is a rare but severe complication of radiofrequency (RF) pulmonary vein isolation (PVI). The objective of this study was to characterize the typical intracardiac course of the PN with a three-dimensional electroanatomic mapping system, to quantify the need for modification of the ablation trajectory to avoid delivering an ablation lesion on sites with PN capture, and to identify very circumscribed areas of common PNC on the routine ablation trajectory of a RF-PVI, allowing fast and effective PN screening for everyday usage. METHODS: We enrolled 137 consecutive patients (63 ± 9 years, 64% men) undergoing PVI. A detailed high output (20 mA) pace-mapping protocol was performed in the right (RA) and left atrium (LA) and adjacent vasculature. RESULTS: The right PN was most commonly captured in the superior vena cava at a lateral (50%) or posterolateral (23%) position before descending along the RA either straight (29%) or with a posterolateral bend (20%). In the LA, beginning deep within the right superior pulmonary vein (RSPV), the right PN is most frequently detectable anterolateral (31%), then descends to the lateral proximal RSPV (23%), and further towards the lateral antral region (15%) onto the medial LA wall (12%). To avoid delivering an ablation lesion on sites with PN capture, modification of ablation trajectory was necessary in 23% of cases, most commonly in the lateral RSPV antrum (81%). No PN injury occurred. CONCLUSION: PN mapping frequently reveals the close proximity of the PN to the ablation trajectory during PVI, particularly in the lateral RSPV antrum. Routine PN pacing should be considered during RF PVI procedures.

[A case of Guillain-Barré syndrome with unilateral diaphragmatic nerve palsy that was longitudinally evaluated using multiple examinations].

The patient, a 50-year-old woman, presented with fever and diarrhea in early July, X. One week later, she noticed muscle weakness in both lower extremities, which upon examination was found to be dominant in the distal muscles, with associated loss of tendon reflexes. We diagnosed the case as Guillain-Barré syndrome. After admission, the patient experienced decreased oxygenation, and a chest X-ray indicated elevation of the left hemidiaphragm. The phrenic nerve conduction studies revealed laterality of the amplitude of compound muscle action potential, and diaphragmatic ultrasonographic examination revealed decreased left diaphragmatic wall motion. We diagnosed the patient with unilateral diaphragmatic nerve palsy and initiated intravenous immunoglobulin and methylprednisolone treatment. After 2 weeks, the patient demonstrated good clinical recovery, increased diaphragmatic nerve amplitude, and improved diaphragmatic movement. We evaluated the longitudinal clinical course of unilateral diaphragmatic nerve palsy in the patient using nerve conduction tests and diaphragmatic echocardiography. The longitudinal evaluation allowed us to assess the pathological condition more sensitively so that the prognosis could be predicted accurately.

Ultrasonographic evaluation of incidence of diaphragmatic paralysis following different volumes of supraclavicular brachial plexus block- A prospective randomized double blinded study.

Background: Ipsilateral diaphragmatic paralysis occurs following supraclavicular blocks such as interscalene blocks, supposedly attributable to the backward diffusion of the local anesthetic (LA) inside the neural sheath. Hence, we have made an attempt to assess diaphragmatic paralysis with ultrasonogram (US) following different volumes of supraclavicular brachial plexus blocks (SCB). Aim: To compare the incidence of diaphragmatic paralysis with different volumes of supraclavicular brachial plexus block using ultrasonogram. Methods: Sixty patients with American Society of Anesthesiologists (ASA) Physical Status I and II were randomized to receive 20, 25, or 30 mL of 0.375% bupivacaine in a double-blinded fashion, and supraclavicular block was performed using ultrasound guidance in an in-plane technique. Diaphragmatic excursion and velocity were studied using a curvilinear 3.5 MHz transducer before and 20 min after giving the block. Results: The incidence of reduction in diaphragmatic excursion and velocity in the group receiving 30 mL was 45% and 45%, respectively, which was higher, whereas it was 47.5% and 32.5% in the 25 mL group and 40% and 25% in the 20 mL group, respectively, which were still lower. Pre- and post-block data were studied using T-test, Kruskal-Wallis test, and Mann-Whitney U test. The probability of reduction in diaphragmatic excursion and velocity in each group was <0.05, which was statistically significant. Conclusion: Our results suggest that there is a greater risk of inadvertent phrenic nerve blockade even in supraclavicular brachial plexus block. The resulting hemidiaphragmatic paralysis is volume dependent, and the overall incidence is higher at greater volumes. Hence, caution is required against compromised perioperative lung function in patients with preexisting cardiorespiratory dysfunction.

Diaphragmatic CMAP Monitoring During Cryoballoon Procedures: Surface vs. Hepatic Recording Comparison and Limitations of This Approach.

BACKGROUND: Compound motor action potential (CMAP) monitoring is a common method used to prevent right phrenic nerve palsy during cryoballoon ablation for atrial fibrillation. OBJECTIVE: We compared recordings simultaneously obtained with surface and hepatic electrodes. METHODS: We included 114 consecutive patients (mean age 61.7 ± 10.9 years) admitted to our department for cryoballoon ablation. CMAP was monitored simultaneously with a hepatic catheter and a modified lead I ECG, whilst right phrenic nerve was paced before (stage 1) and during (stage 2) the right-sided freezes. If phrenic threat was detected with hepatic recordings (CMAP amplitude drop >30%) the application was discontinued with forced deflation. RESULTS: The ratio of CMAP/QRS was 4.63 (2.67-9.46) for hepatic and 0.76 (0.55-1.14) for surface (p < 0.0001). Signal coefficients of variation during stage 1 were 3.92% (2.48-6.74) and 4.10% (2.85-5.96) (p = 0.2177), respectively. Uninterpretable signals were more frequent on surface (median 10 vs. 0; p < 0.0001). For the 14 phrenic threats, the CMAP amplitude dropped by 35.61 ± 8.27% on hepatic signal and by 33.42 ± 11.58% concomitantly on surface (p = 0.5417). Our main limitation was to achieve to obtain stable phrenic capture (57%). CMAP monitoring was not reliable because of pacing instability in 15 patients (13.16%). A palsy occurred in 4 patients (3.51%) because cryoapplication was halted too late. CONCLUSION: Both methods are feasible with the same signal stability and amplitude drop precocity during phrenic threats. Clarity and legibility are significantly better with hepatic recording (sharper signals, less far-field QRS). The two main limitations were pacing instability and delay between 30% CMAP decrease and cryoapplication discontinuation.

Persistent phrenic nerve palsy after atrial fibrillation ablation: Follow-up data from The Netherlands Heart Registration.

BACKGROUND: Persistent phrenic nerve palsy (PNP) is an established complication of atrial fibrillation (AF) ablation, especially during cryoballoon and thoracoscopic ablation. Data on persistent PNP reversibility is limited because most patients recover <24 h. This study aims to investigate persistent PNP recovery, freedom of PNP-related symptoms after AF ablation and identify baseline variables associated with the occurrence and early PNP recovery in a large nationwide registry study. METHODS: In this study, we used data from the Netherlands Heart Registration, comprising data from 9549 catheter and thoracoscopic AF ablations performed in 2016 and 2017. PNP data was available of 7433 procedures, and additional follow-up data were collected for patients who developed persistent PNP. RESULTS: Overall, the mean age was 62 ± 10 years, and 67.7% were male. Fifty-four (0.7%) patients developed persistent PNP and follow-up was available in 44 (81.5%) patients. PNP incidence was 0.07%, 0.29%, 1.41%, and 1.25%, respectively for patients treated with conventional-RF, phased-RF, cryoballoon, and thoracoscopic ablation respectively. Seventy-one percent of the patients fully recovered, and 86% were free of PNP-related symptoms after a median follow-up of 203 (113-351) and 184 (82-359) days, respectively. Female sex, cryoballoon, and thoracoscopic ablation were associated with a higher risk to develop PNP. Patients with PNP recovering ≤180 days had a larger left atrium volume index than those with late or no recovery. CONCLUSION: After AF ablation, persistent PNP recovers in the majority of patients, and most are free of symptoms. Female patients and patients treated with cryoballoon or thoracoscopic ablation are more prone to develop PNP.

Safety and efficacy of cryoballoon versus radiofrequency ablation for atrial fibrillation in elderly patients: A real-world evidence.

BACKGROUND: There are limited data describing the experience of radiofrequency (RF) vs. cryoballoon (CB) ablation for atrial fibrillation (AF) among elderly patients in the United States. METHODS: We conducted a retrospective analysis of patients ≥75 years of age undergoing index RF vs. CB ablation between January 2014 and May 2020 at our center. The choice of ablation technique was left to the operator's discretion. Major complications and efficacy, defined as freedom from any atrial tachyarrhythmia (ATA) lasting ≥30 s after one year of follow-up, were assessed in patients with index RF vs. CB ablation. RESULTS: In our cohort of 186 patients, the median age was 78 (76-81) years, 54.8% were men, and 39.2% had persistent AF. The median CHA2DS2-VASc score was 4 (3-4), while the median duration of AF was 3 (1-7) years. The majority (n = 112, 60.2%) underwent RF ablation. The median procedure time was significantly lower in CB group (197 vs 226.5 min, p=<0.01). The incidence of complications was similar in the two sub-groups (RF: 1.8% vs. CB: 2.7%, p = 0.67). Similarly, arrhythmia-free survival rate on antiarrhythmic drugs at 1-year follow-up remained statistically comparable (63.4% vs. 68.9%, p = 0.33) between patients receiving RF vs. CB ablation. CONCLUSION: The safety and efficacy of RF vs. CB ablation for AF remained comparable in our cohort of patients older than 75 years. CB ablation was associated with a shorter procedure time.

Transient phrenic nerve palsy induced by cardiac catheterisation in an infant.

We report on a 7-month-old male with transient phrenic nerve palsy induced by diagnostic cardiac catheterisation. The phrenic nerve palsy, which is a rare complication, was due to extravascular bleeding from a branch of the internal mammary artery.

Predicting Phrenic Nerve Palsy in Patients Undergoing Atrial Fibrillation Ablation With the Cryoballoon-Does Sex Matter?

Background: Phrenicus nerve palsy (PNP) is a typical complication during pulmonary vein isolation (PVI) using the cryoballoon with the ominous potential to counteract the clinical benefit of restored sinus rhythm. According to current evidence incidence of PNP is about 5-10% of patients undergoing Cryo-PVI and is more frequent during ablation of the RSPV compared to the RIPV. However, information on patient specific characteristics predicting PNP and long-term outcome of patients suffering from this adverse event is sparse. Aim of the Study: To evaluate procedural and clinical characteristics of AF patients with PNP during cryoballoon PVI compared to patients without PNP. Methods and Results: Between 2013 and 2019 we included 632 consecutive AF patients undergoing PVI with the cryoballoon in our study. 84/632 (13.3%) patients experienced a total number of 89 PNP during the ablation procedure. 75/89 (84%) cryothermal induced PNP recovered until the end of the procedure (transient PNP, tPNP), whereas 14/89 (16%) PNP hold beyond the end of the procedure (non-transient PNP, ntPNP). Using multivariate logistic regression, we found that sex and BMI are strong and independent predictors of cryothermal induced non-transient PNP during cryoballoon PVI with an odds ratio of 3.9 (CI: 95%, 1.1-14.8, p = 0.04) for female gender. Interestingly, all patients (14/14, 100%) with a non-transient PNP experienced complete PNP resolution after a mean recovery time of 68 ± 79 days. Conclusion: Our data indicate for the first time, that female sex and lower BMI are independent predictors for non-transient PNP caused by cryoballoon PVI. Fortunately, during follow up all PNP patients resolved completely with a median recovery time of 35 days.