Session 2: Blood and Lymph Systems Flashcards

Question

Compare the Right Lymphatic Duct to the Thoracic Duct

Answer 1

[\*] Right Lymphatic Duct * Drains lymph from the right upper quadrant of the body : right side of the head, right side of the neck, right side of the thorax and right upper limb * Enters the venous system via the right venous angle: angle at the union of the right internal jugular and right subclavian vein [\*] Thoracic Duct * It is the much larger of the two lymphatic ducts of the body * It drains lymph from the rest of the body that is not drained by the right lymphatic duct. * Enters the venous system via the left venous angle: i.e. the angle at the union of the internal jugular vein and subclavian vein * The cisterna chyli dilates to form the beginning of the thoracic duct. Thoracic duct crosses from right to left at T5 vertebra; point of crossing over is the Sternal Angle of Louis

Answer 2

Knowledge of the lymphatic drainage of the head and neck region is important because the presence of an enlarged lymph node may signal disease in the area draining into it. * Anatomical Organisation: Superficial lymph nodes (green ones) and deep lymph nodes are separated by the investing layer of the deep fascia of the neck. Most clinicians classify lymph nodes of the head and neck as regional and terminal lymph nodes. [\*] Regional lymph nodes drain specific anatomical regions of the body (determined by the areas drained, largely superficial – not all though) [\*] Terminal lymph nodes are the point of confluence of lymph drainage from many regional lymph nodes (where region lymph nodes terminate) [\*] Lymph drains from regional nodes into terminal nodes that in turn drain lymph into trunks and eventually into the right lymphatic duct or thoracic duct. Some clinical texts classify lymph nodes of the head and neck as horizontal group and vertical group [\*] Horizontal group of lymph nodes occur as clusters. They may be taken to be on the horizontal plane, irrespective of depth. [\*] Vertical group of lymph nodes occur on a vertical plane that closely follows the course of the internal jugular vein (NB: not an artery) [\*] The vertical lymph nodes are usually difficult to palpate because they occur deeply within tissues of the neck.

Answer 3

[\*] Lie outside of the deep fascia [\*] Are arranged as 2 further assemblies 1. An outer circle * Form a (regional) collar around the lower margins of the head * They are known as the peri-cervical collar nodes * They constitute a circular formation * From the chin to the occiput bilaterally 2. An inner circle * Lying within the outer circle * Surrounding: upper airway passages, openings of the alimentary passage – sometimes known as the innermost circle. * The inner circle involves the pretracheal nodes. [\*] The 2 circles are not parallel to one another The superficial, aka regional nodes of the head and neck comprise the occipital, retroauricular (also called the mastoid nodes), pre/auricular parotid, buccal (also called the facial nodes), the submandibular, submental, anterior cervical, superficial cervical, retropharyngeal, laryngeal (prelaryngeal) and tracheal (paratracheal) nodes.

Answer 4

[\*] Occipital nodes are located on the occipital bone on the back of the skull and drain the back of the scalp [\*] Retroauricular (Mastoid) nodes are behind the ear, over the mastoid process of the skull and drain the scalp over the ear, auricle and the back of the ear canal (external auditory meatus) [\*] Parotid nodes are located on or within the substance of the parotid salivary gland and drain the scalp over the parotid gland, the eyelids, the parotid gland, auricle and external auditory meatus [\*] Buccal (facial nodes) are located on the cheek over the buccinator muscle and drain the lymph that ultimately passes into the submandibular nodes. [\*] Submandibular nodes lie superficial to the submandibular gland just below the lower margin of the jaw and drain the front of the scalp, the nose, the cheek, the upper lip, lower lip (except central part), frontal, maxillary, ethmoidal air sinuses, upper and lower teeth (except incisors), anterior 2/3 of the tongue, floor of the mouth and vestibule and gums. [\*] Submental nodes are located at the submental triangle of the chin and drain the tip of the tongue, floor of the anterior part of the mouth, incisors, central part of the lower lip and skin over the chin. [\*] Anterior cervical nodes lie along the course of the anterior jugular vein in front of the neck and drain the skin and superficial tissues of the front of the neck. [\*] Superficial cervical nodes lie along the course of the external jugular vein and drain the skin over the angle of the jaw, skin over the lower part of the parotid gland and lobe of the ear. [\*] Retropharyngeal lymph nodes lie behind the pharynx in front of the vertebral column and drain the nasopharynx, Eustachian tube and vertebral column [\*] Laryngeal lymph nodes lie in front of the larynx and drain the larynx.

Answer 5

The terminal group of nodes, usually referred to as the deep cervical nodes, receive all the afferent lymph vessels of the head and neck, either directly or indirectly, via one of the regional groups. [\*] They lie within the deep fascia of the neck [\*] They are founded embedded deep within the carotid sheath. [\*] They surround the whole length of the internal jugular vein starting from base of the skull to the level of the clavicle (these deep nodes do not follow the artery) [\*] They ultimately drain all the lymph from the head and neck region. [\*] Most lymph reaching them would have been filtered by nodes of the two circles of the superficial groups. The efferent lymph vessels from the deep cervical nodes join to form the jugular lymph trunks. [\*] On the left side it usually joins the thoracic duct, which enters the left brachiocephalic vein at the junction of the subclavian and internal jugular vein. [\*] On the right side, it enters the venous system at the junction between the subclavian and internal jugular vein via a short right lymphatic duct.

Answer 6

[\*] The deep cervical lymph nodes are divisible into superior/upper deep cervical nodes and inferior/lower deep cervical nodes * The upper deep cervical nodes are situated at the angle between the lower body of the mandible and anterior border of SCM. - One is situated near the posterior belly of the digastric muscle. This is the jugulo-digastric node and often tender and enlarged in infections of the tonsil as it drains the tonsil and tongue. Thus it also known as the tonsillar node * The lower deep cervical nodes are situated in the angle between the sternomastoid muscle and clavicle. - One lies deep to the SCM muscle above the inferior belly of the omohyoid muscle. This is the jugulo-omohyoid node and is associated with lymphatic drainage of the tongue, oral cavity, trachea, oesophagus and thyroid gland. AKA the lingual node. * Another part of the lower deep cervical nodes are the supraclavicular nodes lying in the posterior triangle of the neck, behind the posterior border of the SCM. Efferents from the lower deep cervical group form the jugular lymph trunk which joins the thoracic duct on the left side. - These nodes lie along the course of the accessory nerve; this relationship has bearing on the removal of the accessory nerve affected by a malignancy in the neck.

Answer 7

[\*] Some nodes (supraclavicular nodes) in the root of the neck enlarge in the late stages of malignancies of the thorax and abdomen; an example of this is Virchow’s node associated with gastric carcinoma. * In tumours of the bronchus and some abdominal organs, e.g. stomach, supraclavicular nodes, particularly those on the left side may enlarge, indicating spread. * Backflow of lymph from the thoracic duct can pass into the supraclavicular nodes. This may explain why nodes of the left side are often implicated/raised.

Answer 8

[\*] Nodes of lymphoid tissue assembled as a circle around the entrance of the mouth and nose into the pharynx. [\*] This is Waldeyer’s ring – composed of paired and unpaired nodes. [\*] Paired Nodes: Palatine Tonsil and Tubal Tonsil (Eustachian tube) [\*] Unpaired Nodes: pharyngeal tonsil (adenoid) and lingual tonsil

Answer 9

[\*] Lymphadenitis: infection of the lymph nodes themselves [\*] Lymphangitis: inflammation of the lymph nodes [\*] Lymphoedema: * Chronic pooling of lymph in tissues – usually starts in the feet/legs * Can be result from complications of surgery [\*] Lymphocytosis: * High lymphocyte count from infection, blood cancer lymphoma, autoimmune disorders [\*] Cancers of the lymph system (lymphoma) * Hodgkin’s Disease * Non-Hodgkin’s Disease (usually malignant)

Answer 10

When cervical metastases occur, the surgeon usually performs a block dissection of the cervical nodes. This procedure involves the removal en bloc of the internal jugular vein, the fascia, the lymph nodes and the submandibular salivary gland. The am of the operation is removal of all the lymph tissues on the affected side of the neck.

Answer 11

The common carotid artery pulse can be felt by pressing against the anterior tubercle of the transverse process of C6 vertebra. Pulsation of the artery is also palpable and often visible at the point of its division (Vertebral level C4 – upper border of the thyroid cartilage). [\*] Stand at the patient’s right side with the patient in a supine position (lying on their back). [\*] Index and third fingers are placed on the thyroid cartilage and then slipped laterally between the trachea and sternocleidomastoid muscle. [\*] Carotid artery pulse can be felt just medial to the SCM. [\*] Palpation should be performed low in the neck to avoid pressure on the carotid sinus; pressure on the carotid sinus would cause a reflex drop in blood pressure and heart rate. Indeed sinus massage is sometimes used to reduce heart rate. [\*] Each carotid artery should be evaluated separately; never press on both carotids at the same time

Answer 12

[\*] The pulsations of the internal jugular vein are beneath the SCM and are visible as they are transmitted through the surrounding tissue (the vein is itself not visible). [\*] Because the right internal jugular vein is straighter than the left, only the right internal jugular vein is evaluated – effectively like a direct connection to right atrium * Patient at 45o * Height from sternal angle + 5cm * [\*] It is important to note that although the external jugular vein is easier to visualise (courses superficially over the SCM), its pulsations are less accurate and are not used in clinical examination. The internal jugular vein is a better indication of pressure in the right atrium

Answer 13

* The pads of the fingers should roll the underlying skin over the cranium in circular motion to assess its contour and to feel for the presence of lymph nodes or masses. * Start from the occipital region, move into the posterior auricular region, down into the posterior triangle of the neck, along the SCM, hooking around the muscle to feel deeply, into the anterior of the neck, up to the jaw margin, along the jaw margin and up to the area in front of the ear. * Any nodes that are felt should be assessed for mobility, consistency and tenderness; tender lymph nodes are suggestive of inflammation, whereas fixed, firm nodes are consistent with malignancy. Palpation of Supraclavicular Nodes [\*] Stand behind the patient and place fingers into the medial supraclavicular fossae, deep to the clavicle and adjacent to the SCM. [\*] Ask the patient to take a deep breath while the examiner presses deeply in and behind the clavicle. Any supraclavicular nodes that are enlarged will be felt as the patient inhales.

Answer 14

[\*] The normal gland has a consistency of muscle tissue. Unusual hardness is associated with tumour or scarring. [\*] Tenderness is associated with acute infections or with haemorrhage into the gland. [\*] The thyroid gland can be palpated in 2 ways – one from the front and the second from behind (posterior) to the patient. * In the anterior approach, the examiner sits in front of the patient face to face. By flexing the patient’s neck or turning the chin slightly to the right, the SCM on that side is relaxed. The examiner’s right hand should displace the larynx to the right, and, during swallowing, the displaced right thyroid lobe can be palpated between the examiner’s left thumb and index fingers. The procedure is repeated on the left side to evaluate the left lobe by reversing the hand positions. * In the posterior approach, the examiner stands behind the patient and places both hands around the neck of the patient, whose neck is slightly extended. Use right hand to push the trachea to the right and ask the patient to swallow while your right hand rolls over the thyroid cartilage. As the patient swallows, the examiner’s right hand feels for the thyroid gland against the SCM. Repeat the procedure to feel for the thyroid gland on the left side. [\*] A diffused enlarged thyroid gland will often cause generalised enlargement of the neck. Superficial venous distension in the neck may be associated with goitre. Proptosis: the eyes are displaced forwards and bulging. This may be caused by thyroid dysfunction or a mass in the orbit. See Thyroid Examination Guide on Notability

Answer 15

* The most common symptoms related to the neck include neck mass (lump or swelling) and neck stiffness. If there is associated pain with a mass in the neck; an acute infection would be most likely. Neck masses that have been present for only a few days are commonly inflammatory, whereas those present for months are more likely to be caused by a tumour. A mass that has been present for a long period would often turn out to be benign or congenital. Blockage of the salivary gland duct may produce a mass that changes in size while the patient eats. * The age of the patient is relevant in the assessment of a neck mass. A lump in the neck in a patient under the age of 20 years may be an enlarged tonsillar lymph node or a congenital mass. If the mass is in the midline, it is likely to be a thyroglossal cyst. Between the ages of 20 and 40, thyroid disease is more common. * The location of the mass is also important. Midline masses tend to be benign or dermoid cysts. Lateral masses are frequently neoplastic. Masses in the lateral upper neck may be metastatic lesions from tumours of the head and neck, whereas masses in lateral lower neck may be metastatic from tumours of the breast, lung and stomach. Hoarseness in association with a thyroid nodule suggests vocal cord paralysis by compression/impingement of the recurrent laryngeal nerve by tumour. * Stiffness of the neck is usually caused by spasm of the cervical muscles and is commonly the cause of tension headaches. A sudden occurrence of a stiff neck, fever and headache should be considered as a sign/symptom of possible meningeal irritation. Neck pain may be associated with referred pain from the chest; patients with angina or a myocardial infarction may complain of neck pain.

Answer 16

**Lump Examination: She Cuts the Fish Perfectly** [\*] Three Ss * Site: describe location briefly * Size: use your hand and fingers to estimate if you do not have a ruler with you * Surface/overlying skin [\*] Three Cs * Colour * Contour – is the lump well-defined or irregular * Consistency -?soft/firm/hard [\*] Three Ts * Tenderness * Temperature – is it hot/inflamed? * Transilluminable [\*] Three Fs * Fluctuance - ?fluid-filled cyst * Fixity - ?Is it fixed to the underlying tissue or to the overlying skin * Fields – draining lymph glands in the area [\*] Finally, remember to check for whether the lump is: * Pulsatile (is it an aneurysm?) * Expansile (is it aneurysm?) * Reducible (is it a hernia?)

Answer 17

[\*] Facial Pulse: located on the mandible (lower jawbone) on a line with the corners of the mouth (facial artery) [\*] Temporal Pulse: located on the temple directly in front of the ear (superficial temporal artery)

Session 2: Blood and Lymph Systems Flashcards

(41 cards)