Subcutaneous Veins

Subcutaneous veins of the trunk connect axillary and femoral veins (Figure 3). Superficial system anastomoses with the subfascial system by means of perforating veins, which carry blood from medial aspect of breasts and sternal branches of internal thoracic veins. 

Fig. 2.2a,b. Subcutaneous veins and nerves, a Transverse 12-5 MHz US image obtained over the posterior calf demonstrates the small saphenous vein (white arrowhead) and the adjacent sural nerve (black arrowhead) running in the deep subcutaneous tissue. Detection of the larger vein is a usefiil landmark for recognition of the smaller nerve. Arrows indicate the fascial plane, b Schematic drawing correlation shows subcutaneous veins (white arrowheads) and the nerve (black arrowhead) coursing in the connective spaces which separate fat lobules... 

Placement of vascular access ports is similar to that of a long-term indwelling arterial catheter. A small incision is made over the selected vein and a second incision is made lower in the anterior chest to create a pocket to house the port. The catheter is tuimeled subcutaneously from its entry point into the vein with the tip inside the right atrium. The final position of the catheter is verified by fluoroscopy, secured with sutures, and the subcutaneous pocket is closed. The port septum is easily palpable transcutaneously, and the system may be used immediately. A surgeon typically inserts the vascular access port in an outpatient setting. 

Bolus intravenous, intramuscular, or subcutaneous injections can be administered by a single person by securing the animal s arm through the cage bars (Mazue and Richez, 1982). For safety considerations, many investigators prefer to have the animal physically restrained by a second person before the injection is given. Arterial injections (via the femoral artery) as well as limited or continuous intravenous infusion (via catheterization of the femoral or jugular vein) are other less commonly used parenteral routes in the monkey. 

Unstable angina, non -wave MI Subcutaneous 120 international units/kg ql2h (maximum 10,000 international units/dose) given with aspirin until clinically stable. Prevention of deep vein thrombosis (DVT) or pulmonary edema in the acutely ill patient Subcutaneous 5000 international units once a day. 

Prevention of deep vein thrombosis (DVT) after hip and knee surgery Subcutaneous 30 mg twice a day, generally for 7-10 days. 

Draw 2 ml (0.8 mg) of naloxone into syringe. Inject 0.5 ml (0.2 mg) while needle is still in vein, observe patient for 30 sec for withdrawal signs or symptoms, if no evidence of withdrawal, inject remaining 1.5 ml (0.6 mg) observe patient for additional 20 min for withdrawal signs or symptoms. Subcutaneous Inject 2 ml (0.8 mg) of naloxone observe patient for 45 min for withdrawal signs or symptoms. 

Deep vein tfiromdosis (DVT) Subcutaneous 175 antifactor Xa international units/kg once a day. Continue for af leasf 6 days and unfil paf ienf is suffidenfly anticoagulafed wifh warfarin (INR of 2 or more for 2 consecufive days). 

Parenteral administration This route is applicable for drugs which are inactivated by gastrointestinal tract or absorption is poor when given orally or there is a urgency for fast response in small dose. Intramuscular, intravenous, or subcutaneous routes are commonly used. The intravenous injection (in aqueous solution) is introduced directly into the vein by which a rapid response is produced. The subcutaneous injection are given through the layer of skin, while intramuscular injection, introduced through the skin layer deep into the muscle. The nature of intramuscular injection may be in aqueous or oily solution/suspension form. The aqueous solution will be rapidly absorbed as compared to oily solution or suspension. So, the rate of absorption is dependent on the nature of the preparation. 

Figure 1.5 The blood vessel and nerve supply in the mammary glands of a cow. Circulatory system (arteries, white veins, stippled) h, heart a, abdominal aorta pa, external pudic artery pv, external pudic vein s, subcutaneous abdominal vein c, carotid artery j, jugular vein. Nerves 1, first lumbar nerve 2, second lumbar nerve 3, external spermatic nerve 4, perineal nerve. A and V show blood sampling points for arteriovenous (AV) difference determinations (Mepham, 1987).

The blood of the patient, withdrawn from an artery near the wrist, is allowed to flow through the blood circuit, which includes the dialyzer, usually a blood pump plus monitoring instruments, and is returned to a nearby vein. The connections to the blood vessels are made via the so-called subcutaneous arteriovenous shunt this involves an artificial tube that connects the artery and vein underneath the wrist skin. 

Hull, R.D., et al. "Heparin for 5 Days as Compared with 10 Days in the Initial Treatment of Proximal Venous Thrombosis, N. Eng. J. Med., 1260 (May 3. 1990). Hull, R.D., etal. "Subcutaneous Low-Molecular-Weight Heparin Compared with Continuous Intravenous Hepann in the Treatment ol Proximal-Vein Thrombosis,"... 

The use of traditional (unffactionated) heparin has therefore been replaced by LMWHs to a large extent.18,100 LMWHs are clearly safer and more convenient to their unfractionated counterparts, and these drugs have become the primary method of treating acute venous thrombosis.47,100 LMWHs are now used routinely to prevent or treat deep vein thrombosis (DVT) following various types of surgery or medical conditions (ischemic stroke, cancer).70,127 It has also been suggested that LMWHs will produce optimal effects if they are administered for more than a few days, and some patients who are at high risk for thrombosis may receive LMWHs via subcutaneous injection for several weeks or months.80 Future research will help determine the best way to use LMWHs to prevent or treat venous thrombosis in specific clinical situations. 

Until very recently, the most common means of administering heroin was injection with a hypodermic needle, either intravenously (into a vein called mainlining ), subcutaneously (just under the skin called skin-popping ) or intramuscularly (injected into muscle rather than a vein). Injection by regular users and addicts was preferred because the street drug was so diluted with fillers that injection was the most efficient way to get high. 

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