NORMAL SWALLOWING & DISORDERS OF SWALLOWING: For the #NeuroCriticalCare #Physician & #Anesthesiologist

👅Cranial nerves V,VII,IX,X,XI,XII contributes to swallowing

👅2 brain stem nuclei control swallowing: (1) Nucleus Tractus Solitarius(NTS) which is a pure sensory nucleus in the medulla (2) Nucleus Ambiguous (NA) which is a motor nucleus situated deep in the reticular formation in medulla
 
👅Sensory info sent via cranial nerves to NTS. Interneurons relay info to NA & surrounding reticular formation which sends efferent messages to cranial nerve pathways.

👅Muscles innervated by Trigeminal nerve helps in Mastication, jaw closure, upward movement of larynx, backward movement of tongue to soft palate, tensing and elevation of soft palate and posterior pharyngeal wall constriction

👅Muscles innervated by Facial nerve helps in mandibular depression and contributes to hyoid elevation

👅Glossopharyngeal nerve supplies Stylopharyngeus , contributes to palatoglossus - portion of middle pharyngeal constrictor Ⓜ️NEMO> “Glossy nerve helps Stylish Middle Class”

👅Vagus supplies muscles of soft palate (except Tensor Veli Palatini) - Superior, middle and inferior pharyngeal constrictors - Intrinsic muscles of larynx and muscles of esophagus Ⓜ️NEMO> “Vague nerve helps all classes”
 
👅Recurrent Laryngeal Nerve innervates Cricopharyngeus muscle.
 
👅Hypoglossal nerve innervates all intrinsic and some extrinsic muscles of tongue and geniohyoid ; hence responsible for all movements of the tongue
 
👅Aetiology of swallowing disorders: Stroke, Traumatic Brain Injury, Brain Tumor , Cerebral Palsy, Neuroleptic drug- induced Tardive dyskinesia , Surgery ( Generally damage to the pharyngeal plexus may occur with anterior cervical fusion. Injury of the seventh, tenth, and twelfth cranial nerves may occur with carotid endarterectomy, as these nerves are close to the carotid bifurcation), various forms of dementia, Movement disorders including Parkinsons disease, Multiple Sclerosis , Amyotrophic Lateral Sclerosis (ALS)
 
👅It has been suggested that recovery of swallowing in acute stroke patients may be rapid, warranting reassessment within 3 weeks of the initial swallowing evaluation
 
👅Abnormal volitional cough, abnormal gag,dysarthria,dysphonia, cough after swallow, voice change after swallow are indicators of risk of aspiration after acute stroke
 
👅But many of the neurologic disorders that affect swallowing are progressive; thus swallowing can be expected to decline as the disease worsens.
 
👅Dysarthria may correlate with dysphagia with bulbar Amyotrophic Lateral Sclerosis (ALS). Dysphagia increases as respiratory capacity decreases regardless of the form of ALS. Vital capacity should be consistently measured, as accurate and timely assessment of a clinically relevant decline in respiratory status is crucial for determining the timing of feeding tube placement
 
👅Pneumonia can be a frequent complication in patients with dysphagia owing to CNS disease
 
👅Although an abnormal gag reflex may be apparent in patients with dysphagia resulting from various neurologic disorders, it may be absent in healthy control subjects or it may be normal in patients with neurogenic dysphagia
 
👅The two imaging tools used to evaluate oropharyngeal dysphagia are Video Fluoroscopic Swallow Study (VSS- Gold Standard) and videoendoscopy. The Penetration-Aspiration Scale (PAS) provides an objective way during the VSS to measure the depth, response, and clearance of material entering the larynx and trachea.
 
👅They are also valuable in identifying and teaching maneuvers that may facilitate swallowing and prevent aspiration in a patient.
 
👅When significant aspiration cannot be prevented, alternatives to oral feeding such as percutaneous endoscopic gastrostomy (PEG) tube placement should be considered.
 
👅Patients with oropharyngeal dysphagia owing to CNS lesions are best managed by a team approach including a speech pathologist, neurologist, and gastroenterologist.
 
👅Swallowing therapy may include compensatory or rehabilitative strategies. Compensatory therapy does not change the physiology of the swallow; rather, bolus flow is redirected
 
👅Compensatory strategies consist of manipulation of posture, consistency of the liquid, and sensory input. Facilitatory postures that have been studied in the neurogenic population include chin tuck and head rotation to the weak side
 
👅Rehabilitative therapy includes muscular strengthening and range of motion exercises, thermal-tactile application, and swallowing maneuvers
 
👅Vocal fold medialization is the procedure generally performed to treat aspiration owing to an incompetent larynx
 
👅A tracheotomy may be performed for neurologic patients with chronic aspiration. Although it does not improve swallowing, it facilitates pulmonary toileting
 
👅Laryngotracheal separation is a more radical attempt to prevent chronic aspiration while allowing for oral intake. Although patients may return to oral diets, the ability to phonate is eliminated. If physiologic aspects of swallowing improve sufficiently, this procedure can be reversed, as the glottis is not affected.

#Swallowing , #Anesthesia , #TheLayMedicalMan , #CriticalCare , #Anatomy , #Physiology , #GastroEnterology

ICTAL BRADYCARDIA &ASYSTOLE: AN ENTITY ALL ANESTHESIOLOGISTS SHOULD KEEP IN MIND WHEN SEEING BRADYCARDIA IN A PATIENT WITH EPILEPSY

📌Ictal bradycardia/asystole is a poorly recognised cause of collapse late in the course of a typical complex partial seizure

📌It is important to identify ictal bradycardia as a potential harbinger of lethal rhythms, such as asystole, as this may be one important mechanism leading to sudden unexpected death in epilepsy (SUDEP)

📌Tachycardia is the most common rhythm abnormality occurring in 64–100% of temporal lobe seizures. Ictal bradycardia has been reported in less than 6% of patients with complex partial seizures

📌The ictal bradycardia syndrome occurs in mostly in patients with temporal lobe seizures.

📌It is believed that abnormal neuronal activity during a seizure can affect central autonomic regulatory centres in the brain leading to cardiac rhythm changes.

📌Ictal bradycardia/asystole may be unrecognised until documented during video-electroencephalograph (video EEG)–electrocardiogram (ECG) monitoring in those with refractory epilepsy, often in the context of pre-surgical evaluation

📌Other rhythm abnormalities which can occur are change in heart rate variability, ictal tachycardias and atrioventricular (AV) block

📌If sufficiently severe, the ictal-induced bradyarrhythmia temporarily impairs both cerebral perfusion and cortical function; the result has the dual effect of terminating the seizure, while at the same time triggering syncope with consequent loss of consciousness and postural tone. In essence, a complex partial seizure patient may manifest both seizure and syncope features during the same episode.

📌There are currently no guidelines on who should undergo further cardiovascular investigations ; dual chamber pacemaker implantation has been suggested as a treatment in the long term, for epilepsy patients who manifest this syndrome and suffer repeated falls; but there is not much mention in literature  both about diagnosis and about pharmacological and non pharmacological interventions to counter such episodes when presenting as an emergency situation in the perioperative scenario , especially when the patient is under anesthesia.

#Neurology , #NeuroCriticalCare , #Anesthesia , #LayMedicalMan , #CriticalCare , #Epilepsy , #Cardiology , #CardiacAnesthesia

Reference: Ictal bradycardia and atrioventricular block: a cardiac manifestation of epilepsy; Salman S. Allana  Hanna N. Ahmed  Keval Shah  Annie F. Kelly, Oxford Medical Case Reports, British Journal of Cardiology : Ictal Bradycardia and Asystole Associated with Intractable Epilepsy: A Case Series Elijah Chaila, Jaspreet Bhangu, Sandya Tirupathi, Norman Delanty; Ictal Asystole-Life-Threatening Vagal Storm or a Benign Seizure Self-Termination Mechanism? David G. Benditt, Gert van Dijk, Roland D. Thijs (Editorial:Circulation )