A cannula is a tube that can be inserted into the body for the delivery or removal of fluid or for the gathering of samples. In simple terms, a cannula can surround the inner or outer surfaces of a trocar needle thus extending the effective needle length by at least half the length of the original needle, it is called an intravenous cannula. Its size ranges from 14 to 24 gauge. Different-sized cannula have different colours as coded. Decannulation is the permanent removal of a cannula of a tracheostomy cannula, once a physician determines it is no longer needed for breathing. Cannulae come with a trocar inside; the trocar is a needle. Many types of cannulae exist:Intravenous cannulae are the most common in hospital use. A variety of cannulae are used to establish cardiopulmonary bypass in cardiac surgery. A nasal cannula is a piece of plastic tubing that runs under the nose and is used to administer oxygen. A venous cannula is inserted into a vein for the administration of intravenous fluids, for obtaining blood samples and for administering medicines.
An arterial cannula is inserted into an artery the radial artery, is used during major operations and in critical care areas to measure beat-to-beat blood pressure and to draw repeated blood samples. Insertion of the venous cannula is a painful procedure that can lead to stress. Use of a vapocoolant before cannulation reduces pain during the procedure, without increasing the difficulty of cannulation. Complications may arise in the vein as a result of the cannulation procedure, the four main groups of complication are: hematoma: a collection of blood, which can result from failure to puncture the vein when the cannula is inserted or when the cannula is removed. Selection of an appropriate vein and applying pressure above the insertion point on removal of the cannula may prevent this. Infiltration: when infusate enters the subcutaneous tissue instead of the vein. To prevent this, a cannula with accurate trim distances may be used, it is essential to fix the cannula in place firmly. Embolism: this can be caused by air, a thrombus, or fragment of a catheter breaking off and entering the venous system.
It can cause a pulmonary embolism. Air emboli can be avoided by making sure. A thromboembolism can be avoided by using a smaller cannula. Phlebitis: an inflammation of the vein resulting from mechanical or chemical irritation or from an infection. Phlebitis can be avoided by choosing the site for cannulation and by checking the type of infusate used. A nasal cannula or an oral–nasal cannula consists of a flexible tube with multiple short, open-ended branches for comfortable insertion into the nostrils and/or mouth, may be used for the delivery of a gas, a gas mixture, or to measure airflow into and out of the nose and/or mouth; the removal of a tracheotomy tube is referred to as decannulation. A cannula is used in an emergency procedure to relieve pressure and bloating in cattle and sheep with ruminal tympany, due most to their accidentally grazing wilted legume or legume-dominant pastures alfalfa and red and white clover. Cannulas are a component used in the insertion of the Verichip. Much larger cannulas are used to research about the digestive system of cows.
In aesthetic medicine, a blunt-tip cannula or microcannula is a small tube with an edge, not sharp and an extrusion port or pore near the tip, designed for atraumatic subdermal injections of fluids or gels. Depending on the size of the internal diameter, it can be used either for the injection of cosmetic wrinkle fillers like hyaluronic acid, poly-L-lactic acid, CaHA, etc. or for fat transfer. The advantage of using these is that they are less painful, have less risk of bruising, have less swelling, a better safety profile. Accidental intravascular injections are more difficult with blunt-tip microcannulas, reducing the risk of skin necrosis and embolization to the retinal artery which can result in blindness. Indeed, in May 2015, the USA issued a warning of these risks as an FDA Safety Communication on the "Unintentional Injection of Soft Tissue Filler Into Blood Vessels In the Face". In January 2012, the "Dermasculpt" microcannula was approved by the FDA for use in the United States for use with soft tissue fillers followed by the "Magic Needle", "Softfil", "TSK by Air-Tite", "Sculpt-face".
The primary structural differences between microcannulas is the distance of the extrusion port or pore from the tip, the bluntness of the tip, the flexibility of the shaft (enough flexibility to move around sensitive structures but enough rigidity for precise placement. Since microcannula tips are blunt, a Pilot or Introducer needle is required for entry through the skin and the technique is to thread the microcannula through this tiny opening. Microcannula cosmetic injection techniques have been developed on how to best place cosmetic wrinkle fillers such as the Long MicroCannula Double Cross-Hatched Fan and the Wiggle Progression techniques. In April 2016, the concept of the use of microcannula to inject more than cosmetic fillers was first published; the technique of Microcannula Injected Local Anesthesia was described on the use of microcannula to inject local anesthesia with less pain and swelling. Introduced were Accelerated Healing After Platelet-Rich Pl
Sigma Herculis, Latinized from σ Her, is a binary star system in the northern constellation of Hercules. It has a combined apparent visual magnitude of 4.18, making it bright enough to be visible to the naked eye. Based upon an annual parallax shift of 10.36 mas as seen from Earth, Sigma Herculis is located about 310 light years away from the Sun. The components of this binary system have a separation of 7 AU, are orbiting their common barycenter with a period of 7.4 years and an eccentricity of 0.5. The primary, component A, is magnitude 4.20 B-type main sequence star with a stellar classification of B9 V. At an age of around 404 million years, it is spinning with a projected rotational velocity of 280 km/s; this is giving the star an oblate shape with an equatorial bulge, an estimated 18% larger than the polar radius. The star has an estimated 2.60 times the mass of the Sun, 4.91 times the Sun's radius, is radiating 230 times the solar luminosity from its photosphere at an effective temperature of 9,794 K.
The primary is emitting an infrared excess, suggesting the presence of an orbiting debris disk with a temperature of 80 K located at a radius of 157 AU. There may be a second disk orbiting between 7 and 30 AU with a temperature of 300±100; the Poynting–Robertson lifetime of the dust grains in this inner belt is around 46,000 years − much less than the age of the star. Hence the grains are being replenished through collisions between larger objects. Circumstellar gas is visible in ultraviolet images from the FUSE satellite, being emitted by the circumstellar matter driven outward by the star's radiation; the secondary, component B, is an A-type main-sequence star. It has around 1.5 times the mass of the Sun and 7.4 times the Sun's luminosity
The third USS Neptune, a collier of the U. S. Navy, was laid down by the Maryland Steel Co. Sparrows Point, Md. 23 March 1910. Except for a period out of service at Norfolk Navy Yard 6 May to 5 December 1912, Neptune operated along the east coast and in the Caribbean from Boston to Guantanamo Bay, supporting ships and installations of the Atlantic Fleet into 1913. Continuing her replenishment operations, she made two coaling voyages to Vera Cruz, Mexico in the spring and summer of 1913, returned to Norfolk 8 September, decommissioned there 13 October, was placed in reserve. Neptune commissioned with a naval complement 7 December 1914 and resumed collier service with the Atlantic Fleet. Assigned to the Auxiliary Division, Atlantic Fleet on 28 December 1915, she continued this duty into 1917, she made four voyages to Santo Domingo between June 1916 and February 1917, carrying Marines and mail to support Navy and Marine Corps Units protecting American interests in the Dominican Republic during unrest there.
When the United States entered World War I, Neptune was at Baltimore, loading general cargo. Departing that port, she put into Norfolk to embark a division of the 1st Aeronautical Detachment and sailed 25 May 1917 for France escorted by destroyers Jarvis and Perkins. Arriving at St. Nazaire on 8 June, the ship offloaded her cargo and disembarked her troops, the first American forces to land in Europe for service against the enemy. Neptune sailed for home 28 June; the vessel again resumed service with the Train, Atlantic Fleet, making one voyage to the Caribbean, 12 July to 27 August, operated off the Atlantic Coast, delivering coal to ports in Chesapeake Bay through the end of the war. In 1919, following three voyages to Guantanamo Bay to supply naval forces at the training base there, the collier departed Norfolk on 3 October for the Pacific, calling en route at the Panama Canal Zone and Honduras with Marines and cargo and arriving at San Diego on the 20 October, she operated along the West Coast, coaling ships and supplying naval bases between Bremerton and San Diego.
Returning to the east coast the way she came, the collier arrived at Norfolk on 20 January 1920. Neptune made another coaling voyage to the west coast before departing Philadelphia on 27 August for an eleven-month cruise as part of the Train, Pacific Fleet, she visited Pearl Harbor from 8 September to 25 October and cruised to Valparaiso, Chile in January and February 1921 to coal units of the Battle Force engaged in maneuvers off the Chilean coast. The collier returned to Norfolk 11 July and made one more voyage to the West Coast from 23 July to 30 December and a coaling cruise to the Caribbean, 25 January to 3 April 1922 before decommissioning at Boston on 28 June 1922. Towed by tugs Kalmia and Wandank, Neptune departed Boston 14 December on her last voyage, arriving at Philadelphia three days later. There the ship remained in reserve, until struck from the Navy List 14 May 1938 and sold for scrapping to Northern Metals Co. Philadelphia 18 April 1939; this article incorporates text from the public domain Dictionary of American Naval Fighting Ships