Respiratory Nerve Research Articles

An Independent C1 Nerve Root Variant of the Ansa Cervicalis: A Case Report

The ansa cervicalis (AC) is a neural loop within the carotid triangle of the anterior neck. The loop is traditionally formed by nerve roots C1–C3 of the cervical plexus and extends multiple motor branches. The current case was discovered during a routine dissection as an anatomical variation of the right AC in an 86-year-old Caucasian male cadaver. In this variation, the C1 nerve root did not form the typical loop with the C2 and C3 nerve roots, but instead, remained independent, traveling deep to the superior belly of the omohyoid muscle to supply the sternothyroid muscle. Because no loop was formed, the anatomy of the current case was not an ansa according to the Latin origin of the word, meaning handle or loop. The AC is an important anatomical landmark within the neck and is implicated in laryngeal reinnervation and respiratory nerve stimulation for patients with sleep apnea. The current anatomical variant contributes to a relatively limited catalog of identified anomalies. Knowledge of new AC variations can guide future surgical interventions and further develop the current base of knowledge surrounding the neuromuscular structures of the head and neck.

THORACIC LONGUS NERVE LESION IN A PATIENT WITH ANKYLOSING SPONDYLITIS

The paper presents a 33 - year - old patient who has been suffering from ankylosing spondylitis since the age of 28. Pain in his right shoulder and weakness in his right arm developed after more hours of walking with a backpack. The performed procedure diagnosed a lesion of the long thoracic nerve without of sensory damage. Peripheral nerve injuries long thoracic nerve lead to weakness of the muscles -serratus anterior muscle and result in a protrusion of the medial side of the scapula (scapula alata). It is difficult to raise the arm in the shoulder joint above the horizontal line, that is to raise the shoulder from the chest when the arm is extended and pressed against a fixed object in front of the patient. Due to its long, relatively superficial course, long thoracic nerve is susceptible to injury, either through direct trauma or stretching. The long thoracic nerve, also called Charles Bell’s external respiratory nerve, is a rare isolated nerve damage. The nerve is often injured from carrying a load on his shoulder, with supraclavicular and axillary injuries, blows in the neck area. Injury has been reported in almost all sports, usually occurring from a blow to the ribs with an outstretched arm. Long thoracic nerve can be damaged during breast cancer surgery, especially radical mastectomy that involve the removal of axillary lymph nodes. It is a common lesion in spinal surgeries. Key words: Lesion, long thoracic nerve, ankylosing spondylitis

Changes in respiratory structure and function after traumatic cervical spinal cord injury: observations from spinal cord and brain.

Respiratory difficulties and mortality following severe cervical spinal cord injury (CSCI) result primarily from malfunctions of respiratory pathways and the paralyzed diaphragm. Nonetheless, individuals with CSCI can experience partial recovery of respiratory function through respiratory neuroplasticity. For decades, researchers have revealed the potential mechanism of respiratory nerve plasticity after CSCI, and have made progress in tissue healing and functional recovery. While most existing studies on respiratory plasticity after spinal cord injuries have focused on the cervical spinal cord, there is a paucity of research on respiratory-related brain structures following such injuries. Given the interconnectedness of the spinal cord and the brain, traumatic changes to the former can also impact the latter. Consequently, are there other potential therapeutic targets to consider? This review introduces the anatomy and physiology of typical respiratory centers, explores alterations in respiratory function following spinal cord injuries, and delves into the structural foundations of modified respiratory function in patients with CSCI. Additionally, we propose that magnetic resonance neuroimaging holds promise in the study of respiratory function post-CSCI. By studying respiratory plasticity in the brain and spinal cord after CSCI, we hope to guide future clinical work.

Increased Sensitivity of Cough Reflex is Not the Mechanism of Cough Attributed to Laryngopharyngeal Reflux

In laryngopharyngeal reflux (LPR) patients acid reaches laryngopharyngeal area and stimulates/sensitizes respiratory nerve terminals mediating cough. We addressed several hypothesis: if stimulation of respiratory nerves is responsible for coughing then acidic LPR should correlate with coughing and proton pump inhibitor (PPI) treatment should reduce both LPR and coughing. If sensitization of respiratory nerves is responsible for coughing then cough sensitivity should correlate with coughing and PPI should reduce both coughing and cough sensitivity. In this prospective single center study, patients with positive reflux symptom index (RSI > 13) and/or reflux finding score (RFS > 7) and ≥1 LPR episode/24 hours were enrolled. We evaluated LPR by dual channel 24-hour pH/impedance. We determined number of LPR events with pH drop at levels 6.0, 5.5, 5.0, 4.5, and 4.0. Cough reflex sensitivity was determined as lowest capsaicin concentration causing at least 2/5 coughs (C2/C5) by single breath capsaicin inhalation challenge. For statistical analysis C2/C5 values were -log transformed. Troublesome coughing was evaluated on the scale 0-5. We enrolled 27 LPR patients. The number of LPR events with pH 6.0, 5.5, 5.0, 4.5, and 4.0 was 14[8-23],4[2-6],1[1-3],1[0-2] and 0[0-1], respectively. There was no correlation between number of LPR episodes at any pH level and coughing (Pearson range -0.34 to 0.21, P = NS). There was no correlation between cough reflex sensitivity C2/C5 and coughing (R = -0.29 to 0.34, P = NS). Of patients that completed PPI treatment, 11 had RSI normalized (18.36 ± 2.75 vs. 7 ± 1.35, P < 0.01). There was no change in cough reflex sensitivity in PPI-responders. C2 threshold was 1.41 ± 0.19 vs. 1.2 ± 0.19 (P = 0.11) before and after PPI. No correlation between cough sensitivity and coughing and no change in cough sensitivity despite improvement of coughing by PPI argue that an increased cough reflex sensitivity is not mechanism of cough in LPR. We identified no simple relationship between LPR and coughing suggesting that this relationship is more complex.

Effect of cisplatin on respiratory activity in neonatal rats.

One side effect of cisplatin, a cytotoxic platinum anticancer drug, is peripheral neuropathy; however, its central nervous system effects remain unclear. We monitored respiratory nerve activity from the C4 ventral root in brainstem and spinal cord preparations from neonatal rats (P0-3) to investigate its central effects. Bath application of 10-100μM cisplatin for 15-20min dose-dependently decreased the respiratory rate and increased the amplitude of C4 inspiratory activity. These effects were not reversed after washout. In separate perfusion experiments, cisplatin application to the medulla decreased the respiratory rate, and application to the spinal cord increased the C4 burst amplitude without changing the burst rate. Application of other platinum drugs, carboplatin or oxaliplatin, induced no change of respiratory activity. A membrane potential analysis of respiratory-related neurons in the rostral medulla showed that firing frequencies of action potentials in the burst phase tended to decrease during cisplatin application. In contrast, in inspiratory spinal motor neurons, cisplatin application increased the peak firing frequency of action potentials during the inspiratory burst phase. The increased burst amplitude and decreased respiratory frequency were partially antagonized by riluzole and picrotoxin, respectively. Taken together, cisplatin inhibited respiratory rhythm via medullary inhibitory system activation and enhanced inspiratory motor nerve activity by changing the firing property of motor neurons.

Does acute flaccid myelitis cause respiratory failure in children?

Acute flaccid myelitis (AFM) is a rare disease that affects spinal cord gray matter, results in acute flaccid weakness of one or more limbs and predominantly involves the cervical spinal cord, which places patients at higher risk for respiratory failure. Our study aims to describe respiratory failure in pediatric AFM patients with emphasis on the need for assisted ventilation and respiratory nerve involvement from an acute and long-term perspective. We reviewed the medical records of patients diagnosed with AFM seen in a multidisciplinary clinic for persistent limb weakness between 2016 and 2020. We studied 54 patients, 35% were female. The median age of patients at illness onset was 5 years (range 7 months-19 years). The median age of patients at the time of study was 8.5 years (range 2-20 years). Eleven patients (20%) required assisted ventilation for acute respiratory failure. Of those that experienced acute respiratory failure, 81% developed chronic respiratory failure. Fifty-six percent of patients with chronic respiratory failure were able to wean off assisted ventilation by 1year. All patients that experienced unilateral diaphragm impairment with AFM onset experienced acute and chronic respiratory failure. Many patients with AFM may experience respiratory compromise and develop chronic respiratory failure. However, most of these patients can be weaned off ventilatory support by 1 year from illness onset. Most children with unilateral diaphragm impairment can sustain adequate ventilation without the need for long-term ventilatory support.

Characteristics of COVID and post COVID polyneuropathies in adults and pediatrics: an Egyptian sample

BackgroundThe aim of this study is to describe the different forms of polyneuropathy associated with coronavirus disease 2019 (COVID-19) as a secondary neurological complication for (COVID-19) and the outcome from different therapeutic regimens in adults and pediatrics in first and second waves of the pandemic.Case presentationThis study was conducted on 42 patients, they were divided into two groups, group (A) and group (B) in first and second waves respectively. Twenty-five patients presented by ascending weakness preceded by fever, dry cough and respiratory distress, electromyography (EMG) and nerve conduction (NC) studies done and confirmed the clinical diagnosis of demyelinating polyneuropathy. Eight patients presented by acute flaccid quadriparesis, more severe in upper limbs preceded by fever and diarrhea diagnosed as acute axonal polyneuropathy. Five patients presented by severe fatigue and progressive weakness of both lower and upper limbs, they developed fever and cough 10 days after the neurological symptoms. EMG and NC done and confirmed clinical diagnosis of polyneuropathy of demyelinating with secondary axonal picture. Four patients presented 30 to 40 days after their recovery form corona virus infection with gradual progressive weakness of both upper and lower limbs over 2 to 3 months duration, mainly the proximal muscles of lower limbs were affected with areflexia. EMG and NC done and confirmed the diagnosis of chronic inflammatory demyelinating polyneuropathy (CIDP).ConclusionWe should gain a better understanding of the underlying pathophysiology and therapeutic options of polyneuropathies related to COVID-19, which will have an impact on the treatment of the COVID related respiratory failure presenting with neuropathy.

The Bicentenary of Bell's Description of the Neuroanatomical Basis of Facial Paralysis: Historical Remarks.

Charles Bell was a talented and versatile Scottish anatomist, neurophysiologist, artist, and surgeon. On July 12, 1821, he reported his studies regarding facial innervation in the essay "On the Nerves," read before the Royal Society in London. Since then, idiopathic peripheral facial paralysis has been named "Bell's palsy." He was the first author to describe the neuroanatomical basis of facial paralysis, in an essay enriched by beautifully self-made illustrations. The aim of this article is to trace the history of Bell's description of the neuroanatomy of the facial nerve, reexamining his 1821 article, in which he stated that the lower facial expression muscles were dually innervated by both the fifth and seventh cranial nerves. In 1829, he rectified this conclusion, recognizing the exclusive role of the facial nerve, which he defined as the "respiratory nerve." We offer a tribute to this polymath scientist on the bicentenary of his 1821 publication.

Changes in the autonomic and respiratory patterns in mice submitted to short-term sustained hypoxia.

What is the central question of this study? Do mice submitted to sustained hypoxia present autonomic and respiratory changes similarly to rats? What is the main finding and its importance? Arterial pressure in the normal range, reduced baseline heart rate and tachypnoea were observed in behaving sustained hypoxia mice. Recordings in the in situ preparation of mice submitted to sustained hypoxia show an increase in cervical vagus nerve activity and a simultaneous reduction in thoracic sympathetic nerve activity correlated with changes in the respiratory cycle. Therefore, mice are an important model for studies on the modulation of sympathetic activity to the cardiovascular system and the vagus innervation of the upper airways due to changes in the respiratory network induced by sustained hypoxia. Short-term sustained hypoxia (SH) in rats induces sympathetic overactivity and hypertension due to changes in sympathetic-respiratory coupling. However, there are no consistent data about the effect of SH on mice due to the different protocols of hypoxia and difficulties associated with the handling of these rodents under different experimental conditions. In situ recordings of autonomic and respiratory nerves in SH mice have not been performed yet. Herein, we evaluated the effects of SH ( =0.1 for 24h) on baseline mean arterial pressure (MAP), heart rate (HR), respiratory frequency (fR ) and responses to chemoreflex activation in behaving SH mice. A characterization of changes in cervical vagus (cVN), thoracic sympathetic (tSN), phrenic (PN) and abdominal (AbN) nerves in SH mice using the in situ working heart-brainstem preparation was also performed. SH mice presented normal MAP, significant reduction in baseline HR, increase in baseline fR , as well as increase in the magnitude of bradycardic response to chemoreflex activation. In in situ preparations, SH mice presented a reduction in PN discharge frequency, and increases in the time of expiration and incidence of late-expiratory bursts in AbN activity. Nerve recordings also indicated a significant increase in cVN activity and a significant reduction in tSN activity during expiration in SH mice. These findings make SH mice an important experimental model for better understanding how changes in the respiratory network may impact on the modulation of vagal control to the upper airways, as well as in the sympathetic activity to the cardiovascular system.

Comparison of analgesic efficacy between rectus sheath blockade, intrathecal morphine with bupivacaine, and intravenous patient-controlled analgesia in patients undergoing robot-assisted laparoscopic prostatectomy: a prospective, observational clinical study

BackgroundWe explored the analgesic outcomes on postoperative day (POD) 1 in patients undergoing robot-assisted laparoscopic prostatectomy (RALP) who received intravenous patient-controlled analgesia (IV-PCA), rectus sheath bupivacaine block (RSB), or intrathecal morphine with bupivacaine block (ITMB).MethodsThis was a prospective, observational clinical trial. Patients were divided into three groups: IV-PCA (n = 30), RSB (n = 30), and ITMB (n = 30). Peak pain scores at rest and with coughing, cumulative IV-PCA drug consumption, the need for IV rescue opioids, and Quality of Recovery-15 (QoR-15) questionnaire scores collected on POD 1 were compared among the groups.ResultsThe preoperative and intraoperative findings were comparable among the groups; the ITMB group required the least remifentanil of all groups. During POD 1, the ITMB group reported lower levels of pain at rest and with coughing, compared with the other two groups. During POD 1, incidences of severe pain at rest (10.0% vs. 23.3% vs. 40.0%) and with coughing (16.7% vs. 36.7% vs. 66.7%) were the lowest in the ITMB group compared with the RSB and IV-PCA groups, respectively. After adjustment for age, body mass index, diabetes mellitus, hypertension, and intraoperative remifentanil infusion, severe pain at rest was 0.167-fold less common in the ITMB group than in the IV-PCA group, while pain with coughing was 0.1-fold lower in the ITMB group and 0.306-fold lower in the RSB group, compared with the IV-PCA group. The ITMB group required lower cumulative IV-PCA drug infusions and less IV rescue opioids, while exhibiting a better QoR-15 global score, compared with the other two groups. Complications (nausea and pruritus) were significantly more common in the ITMB group than in the other two groups; however, we noted no ITMB- or RSB-related anesthetic complications (respiratory depression, post-dural headache, nerve injury, or puncture site hematoma or infection), and all patients were assessed as Clavien-Dindo grade I or II during the hospital stay.ConclusionAlthough ITMB induced complications of nausea and pruritus, this analgesic technique provided appropriate pain relief that enhanced patient perception related to early postoperative recovery.Trial registrationClinical Research Information Service, Republic of Korea, (approval number: KCT0005040) on May 20, 2020

Respiratory pathology in the Optn-/- mouse model of Amyotrophic Lateral Sclerosis

Amyotrophic Lateral Sclerosis (ALS) is a devastating neurodegenerative disorder that results in death due to respiratory failure. Many genetic defects are associated with ALS; one such defect is a mutation in the gene encoding optineurin (OPTN). Using an optineurin null mouse (Optn-/-), we sought to characterize the impact of optineurin deficiency on respiratory neurodegeneration. Respiratory function was assessed at 6 and 12 mo of age using whole body plethysmography at baseline during normoxia (FiO2: 0.21; N2 balance) and during a respiratory challenge with hypoxia and hypercapnia (FiCO2: 0.07, FiO2: 0.10; N2 balance). Histological analyses to assess motor neuron viability and respiratory nerve integrity were performed in the medulla, cervical spinal cord, hypoglossal nerve, and phrenic nerve. Minute ventilation, peak inspiratory flow, and peak expiratory flow are significantly reduced during a respiratory challenge in 6 mo Optn-/-mice. By 12 mo, tidal volume is also significantly reduced in Optn-/- mice. Furthermore, 12mo Optn-/- mice exhibit hypoglossal motor neuron loss, phrenic and hypoglossal dysmyelination, and accumulated mitochondria in the hypoglossal nerve axons. Overall, these data indicate that Optn-/- mice display neurodegenerative respiratory dysfunction and are a useful model to study the impact of novel therapies on respiratory function for optineurin-deficient ALS patients.

Characteristics of immune response in patients with acute chronic maxillary sinusitis associated with intra-cellular bacterial infections

Currently, chronic inflammatory pathology of paranasal sinuses mostly affecting maxillary antrum is one of the pressing issues for health care. Over the last two decades, a great etiological importance in inducing inflammation in paranasal sinuses was referred to bacterial intracellular infections caused by Mycoplasma and Chlamydia. In particular, Chlamydia, whose life cycle is closely linked to residence inside host cells defines them as pathogenic obligate intracellular gram-negative bacteria, whereas Mycoplasma is a membrane-associated microorganism able to self-replication and long persistence on host cellular membranes. Increased incidence of chronic pathology in paranasal sinuses associated with intracellular infection is shaped by a range of circumstances, primarily increased prevalence of immunocompromised subjects, worsened social and ecological conditions, uncontrolled and unjustified administration of available of antimicrobials and anti-septic agents, hormone preparations altering community of extracellular microbe populations (microbiocenoses), inhabiting natural biotope in the upper respiratory tract mucosa. These factors contribute to the lowering colony resistance, entrance and propagation of Chlamydia and Mycoplasma as a monoor mixed infection. Upon that, mixed variants of Chlamydia-Mycoplasma infection are characterized by development of more severe sinusitis accompanied with diverse complications in the lower respiratory tract, digestive tract, urinary and nerve system. There were examined 189 subjects for assessing epidemiologic characteristics and features of systemic and mucosal immune responses in patients with exacerbated chronic maxillary sinusitis associated with intracellular bacterial infection. Presence of intracellular bacterial infection was confirmed by laboratory tests: direct immune fluorescent analysis and PCR. It was found that high prevalence of Сhlamydia trachomatis, Chlamydophila pneumoniae and Mycoplasma pneumoniae in patients with exacerbated chronic inflammatory pathology of paranasal sinuses. Comparing laboratory test data for patients with identified intracellular bacterial pathogens vs. those with negative results revealed a common trend in pathologic immune-related changes that fits to typical host anti-infection response manifested by inflammatory process. Besides, we described features of immune reactivity in patients with verified Chlamydia infection including more pronounced unbalance in Т cell immunity as well as evelated parameters of humoral immunity in patients with verified Chlamydia and Mycoplasma infection.

P37 LIMITED MEDIASTINAL LYMPHADENECTOMY FOR ELDERLY PATIENTS OVER 75 YEARS OLD WITH THORACIC ESOPHAGEAL CARCINOMA IS PERMISSIBLE

Abstract Aim The aim of this study is to investigate the influence on postoperative complications and survival rate by the difference in the number of mediastinal lymph node dissection for elderly patients over 75 years old with thoracic esophageal carcinoma. Background &amp; Methods In esophagectomy for thoracic esophageal carcinoma, mediastinal lymphadenectomy is an essential procedure for the radical cure and also an invasive procedure. In elderly patients, especially, the postoperative complications are likely to be serious, and less-invasive surgical procedure is preferred. We sometimes perform limited mediastinal lymphadenectomy for elderly patients with thoracic esophageal carcinoma depending on the case, but the influence on survival rate is controversial. 55 patients who underwent esophagectomy for thoracic esophageal carcinoma over 75 years old between 2007 and 2015 were included in this study. Patients were divided into two groups by number of mediastinal lymph node dissection: normal group (15 or more: n=28) and limited group (less than 15: n=27). The short- and long-term outcomes were retrospectively examined to those groups. Results The median age of the normal and limited group were 76.5 and 79, respectively. No significant differences were demonstrated in clinical stage, operation time and estimated blood loss between these groups. The incidences of postoperative circulatory complications were 37.0% in the normal group and 25.0% in the limited group, but there was no statistically significant difference (P = 0.43). In the normal group, the postoperative respiratory complications (46.4 vs. 14.8%, P = 0.011) and recurrent laryngeal nerve paralysis (21.4 vs. 3.7%, P = 0.049) were significantly higher than that of the limited group. The 5-year overall survival rate (OS) and the 5-year relapse free survival rate (RFS) did not show statistical differences between the normal and limited group (OS: 45.0 vs. 46.0%, P = 0.44; RFS: 39.7 vs. 37.7%, P = 0.57). Conclusion In the limited mediastinal lymphadenectomy group, the postoperative respiratory complications and recurrent laryngeal nerve paralysis have a low occurrence rate. There was no difference in the survival rate between these groups. It was considered that limited mediastinal lymphadenectomy for elderly patients with thoracic esophageal carcinoma is permissible to prevent postoperative complications.

Severe diaphragmatic dysfunction with preserved activity of accessory respiratory muscles in a critically ill child: a case report of failure of neurally adjusted ventilatory assist (NAVA) and successful support with pressure support ventilation (PSV)

BackgroundNeurally adjusted ventilatory assist (NAVA) is an alternative to pressure support ventilation (PSV) potentially improving patient-ventilator interaction. During NAVA, diaphragmatic electrical activity (EAdi) is used to trigger the ventilator and perform a proportional respiratory assistance. We present a case in which the presence of severe bilateral diaphragmatic dysfunction led to a failure of NAVA. On the contrary, the preserved activity of the accessory inspiratory muscles allowed a successful respiratory assistance using PSV.Case presentationA 10-year-old girl developed quadriplegia after neurological surgery. Initially, no spontaneous breathing activity was present and volume controlled ventilation was necessary. Two months later spontaneous inspiratory efforts were observed and a maximal negative inspiratory force of − 20 cmH2O was recorded. In addition, a NAVA nasogastric tube was placed. The recorded EAdi signal, despite showing a phasic activity, had a very low amplitude (1–2 μV). Two brief (15 min) breathing trials to compare PSV (pressure support = 8 cmH2O) with NAVA (Gain = 5 cmH2O/μV, inspiratory trigger = 0.3 μV) were performed. On PSV, the patient was well adapted with stable tidal volumes, respiratory rates, minute ventilation, end-tidal and venous carbon dioxide levels. When switched to NAVA, her breathing pattern became irregular and she showed clear sign of increased work of breathing and distress: tidal volume dropped and respiratory rate rose, leading to an increase in total minute ventilation. Nevertheless, end-tidal and venous carbon dioxide rapidly increased (from 49 to 55 mmHg and from 52 to 57 mmHg, respectively). An electromyographic study documented an impairment of the diaphragm with preserved activity of the accessory inspiratory muscles.ConclusionsWe document the failure of mechanical assistance performed with NAVA due to bilateral diaphragmatic dysfunction in a critically ill child. The preserved activity of some accessory respiratory muscles allowed to support the patient effectively with pressure support ventilation, i.e. by applying a pneumatic trigger. The present case underlines (i) the importance of the integrity of the respiratory centers, phrenic nerves and diaphragm in order to perform NAVA and (ii) the possible diagnostic role of EAdi monitoring in complex cases of weaning failure.

Efficacy of ultrasound-guided quadratus lumborum block for analgesia after laparoscopic cholecystectomy

Objective To evaluate the efficacy of ultrasound-guided quadratus lumborum block for analgesia after laparoscopic cholecystectomy. Methods Sixty American Society of Anesthesiologists physical statusⅠorⅡ patients, aged 18-64 yr, with body mass index of 20-27 kg/m2, scheduled for elective laparoscopic cholecystectomy, were divided into 2 groups (n=30 each) using a random number table method: ultrasound-guided transversus abdominis plane block group (group T) and ultrasound-guided quadratus lumborum block group (group Q). In T and Q groups, bilateral ultrasound-guided transversus abdominis plane block and quadratus lumborum block were performed after general anesthesia induction, respectively, with 0.25% ropivacaine 20 ml for each side.All the patients received patient-controlled intravenous analgesia with morphine after surgery, and visual analoge scale scores were maintained ≤3 in the two groups.The cumulative consumption of morphine was recorded at 2, 4, 6, 12, 24 and 48 h after surgery.The occurrence of adverse reactions such as nausea, vomiting, pruritus, over-sedation and respiratory depression was observed and recorded in the analgesic period.The operation time for nerve blocks and nerve blocks-related complications such as bleeding, accidental puncture into the abdominal cavity or intestinal injuries were recorded. Results Compared with group T, the cumulative consumption of morphine was significantly decreased at 6, 12, 24 and 48 h after surgery in group Q (P 0.05). There were no adverse reactions such as nausea, vomiting, pruritus, over-sedation and respiratory depression or nerve blocks-related complications in the two groups. Conclusion Ultrasound-guided quadratus lumborum block provides better efficacy than transversus abdominis plane block when used for analgesia after laparoscopic cholecystectomy. Key words: Nerve block; Analgesia; Ultrasonography; Laparoscopy

The Disputed Discovery of Facial and Trigeminal Nerve Function: Revisiting the Contributions of Herbert Mayo and Charles Bell.

The first description of the voluntary motor function of the facial nerve and separate sensory-motor contributions of the trigeminal nerve is most commonly attributed to Charles Bell. However, a review of the original scientific accounts and subsequent historical publications question the validity of this credit. The objective of the present historical analysis is to clarify the contributions of Herbert Mayo toward discovering the functions of the fifth and seventh cranial nerves and to raise awareness of this historical controversy within the medical literature. Review of Charles Bell's and Herbert Mayo's original dissertations published between 1821 and 1823, and subsequent reports relevant to these primary works. Bell's submissions to the Royal Society of London in 1821 and 1822 describe the seventh nerve as the "respiratory nerve of the face" responsible for involuntary coordination of facial movement with the organs of respiration. Separately, Bell states that the fifth nerve is responsible for sensibility and voluntary movement of the facial muscles. In these accounts, Bell only peripherally alludes to the motor function of the seventh nerve and often comments inaccurately on fifth and seventh cranial nerve innervation. In contrast, in 1822 and 1823, Herbert Mayo first accurately and unequivocally defined the voluntary motor function of the facial nerve and sensory-motor function of the trigeminal nerve on the basis of his detailed experiments. The ultimate transfer of acknowledgment to Bell was rooted in surreptitious reworking of Bell's original dissertations and personal attacks against Mayo rather than arguments of scientific merit. Several notable clinicians and anatomists have contributed to our current understanding of the anatomy and physiology of the facial and trigeminal nerves, including Charles Bell; however, Herbert Mayo should be remembered for first providing a more accurate and clear description of their separate functions.

Nursing Implications for the Management of Lymphatic Malformation in Children [Formula: see text

Lymphatic malformation (LM) is a benign congenital childhood growth that presents primarily at birth, with the remainder becoming evident by age 2 years. LM can cause devastating complications such as respiratory failure, dyspnea, dysphagia, organ compression, and nerve compression. Surgery is the preferred treatment option, although resection is not always an option due to the anatomic location of the malformation. Other treatments that have been tried with success include sclerotherapy, radiofrequency ablation, propranolol, and sirolimus. Nurses have an important role in caring for the child with LM, as with any complex disease. Nurses provide care at the bedside, education to the family, case coordination, and psychosocial support. LM is a rare disease in infancy necessitating pediatric nurses to support families through prolonged treatments and potential complications.

Power spectral analysis of hypoglossal nerve activity during intermittent hypoxia-induced long-term facilitation in mice.

Power spectral analyses of electrical signals from respiratory nerves reveal prominent oscillations above the primary rate of breathing. Acute exposure to intermittent hypoxia can induce a form of neuroplasticity known as long-term facilitation (LTF), in which inspiratory burst amplitude is persistently elevated. Most evidence indicates that the mechanisms of LTF are postsynaptic and also that high-frequency oscillations within the power spectrum show coherence across different respiratory nerves. Since the most logical interpretation of this coherence is that a shared presynaptic mechanism is responsible, we hypothesized that high-frequency spectral content would be unchanged during LTF. Recordings of inspiratory hypoglossal (XII) activity were made from anesthetized, vagotomized, and ventilated 129/SVE mice. When arterial O2 saturation (SaO2) was maintained >96%, the XII power spectrum and burst amplitude were unchanged for 90 min. Three, 1-min hypoxic episodes (SaO2 = 50 ± 10%), however, caused a persistent (>60 min) and robust (>400% baseline) increase in burst amplitude. Spectral analyses revealed a rightward shift of the signal content during LTF, with sustained increases in content above ∼125 Hz following intermittent hypoxia and reductions in power at lower frequencies. Changes in the spectral content during LTF were qualitatively similar to what occurred during the acute hypoxic response. We conclude that high-frequency content increases during XII LTF in this experimental preparation; this may indicate that intermittent hypoxia-induced plasticity in the premotor network contributes to expression of XII LTF.

Hypoglossal long term facilitation shifts the power spectral density to higher frequencies

The frequency content of electrical activity in respiratory nerves shows distinct bands of increased content (power). Above approximately 75 Hz these bands show coherence across different respiratory nerves suggesting a pre‐synaptic mechanism. Since most evidence indicates that the mechanism(s) of intermittent hypoxia‐induced long‐term facilitation (LTF) are post‐synaptic, we hypothesized that the hypoglossal (XII) spectral content above 75 Hz would remain stable during LTF in urethane anesthetized, vagotomized and ventilated adult 129SVE mice. When arterial O2 saturation (SaO2) was held at &gt;97% the XII power spectrum and burst amplitude were unchanged for 90 min. Three 1‐min hypoxic episodes (SaO2=50±10), however, caused a persistent (&gt;60 min) and very robust (&gt;400%) amplitude increase. 60 min following intermittent hypoxia, spectral analyses revealed decreased power over 20‐50 Hz (P&lt;0.05) and a substantial increase at 150‐200 Hz (P&lt;0.05). Thus, the hypothesis was rejected, and we conclude that LTF in this preparation is associated with increased high frequency content of the XII neurogram.Funding: Parker B. Francis Fellowship and 1 K08 HD077040‐01A1 (MKE), 2R01HD052682‐06A1 (DDF).

Specific Respiratory Neuron Types Have Increased Excitability That Drive Presympathetic Neurones in Neurogenic Hypertension

A major aspect of hypertension is excessive sympathetic activity but the reasons for this remain elusive. Sympathetic tone is increased in the spontaneously hypertensive (SH) rat reflecting, in part, enhanced respiratory-sympathetic coupling. We aimed to identify which respiratory cells might have altered properties. Using the working heart-brain stem preparation, we monitored simultaneously sympathetic and respiratory nerve activity in combination with intracellular recordings of physiologically characterized medullary presympathetic or respiratory neurons. In SH rats, respiratory modulation of both inspiratory and postinspiratory phases of sympathetic activity was larger relative to Wistar rats. An additional burst of sympathetic activity in the preinspiratory phase was also present in SH rats. After synaptic isolation of rostral medullary presympathetic neurons, there was no difference in their excitability compared with neurons in Wistar rats. Rather, both pre-Bötzinger preinspiratory and Bötzinger postinspiratory neurons had increased neuronal excitability in SH rats relative to Wistar rats; this was attributed to higher input resistance/reduced leak current in preinspiratory neurons and reduced calcium activated potassium conductance in postinspiratory neurons. Thus, the respiratory network of the SH rat is reconfigured to a pattern dominated by heightened excitability of preinspiratory and postinspiratory neurons. These neurons both provide augmented excitatory synaptic drive to rostral medullary presympathetic neurons contributing to excessive sympathetic nerve activity associated with hypertension in the in situ SH rat. Our data indicate selective modulation of potassium conductances in 2 subsets of respiratory neurons contributing to neurogenic hypertension.