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In a series of 160 such patients order principen 500mg, 64% had complete long-term resolution of symptoms after pancreatic sphincterotomy [139] discount 500 mg principen visa. Pancreatic sphincterotomy should be undertaken only by expert endoscopists at specialized tertiary centers that frequently deal with this disorder discount 500 mg principen overnight delivery. Biliary sludge/microlithiasis Biliary sludge is a viscous suspension of uid that contains small stones cheap principen 250mg overnight delivery, cholesterol monohydrate crystals, or calcium bilirubinate granules [140]. Sludge appears at ultrasonography as low-amplitude layers in the most dependent part of the gallbladder that shift with positioning and that do not exhibit acoustic shadowing [141]. For example, in a series of 31 patients who had idiopathic acute pancreatitis, 23 patients (74%) had biliary sludge detected by ultrasonography or had cholesterol monohydrate or calcium bilirubinate crystals detected by biliary microscopy [142]. Therapy Team approach A team approach with specialist consultation and referral helps optimize the management of severe and complicated pancreatitis. The gastrointestinal surgeon performs necrosectomy for infected pancreatic necrosis. Triage Almost all patients who have acute pancreatitis should be hospitalized for supportive therapy and optimal management, especially for the rst episode of pancreatitis, in which there is a need to determine the specic cause. Occasionally patients who have chronic pancreatitis may be able to manage a smoldering episode of recurrent pancreatitis at home. The three goals of therapy for acute pancreatitis are general supportive therapy to prevent complications, directed therapy for specic causes of pancreatitis, and early recognition and aggressive treatment of complications. General supportive therapy Patients who have acute pancreatitis generally are severely intravascularly depleted on presentation from the profound loss of intravascular uid into the inamed pancreas and abdomen. This hypovolemia can manifest clinically as hemoconcentration, hypotension, tachycardia, dry mucous membranes, poor skin turgor, and oliguria. Such patients should be hydrated 3 intravenously aggressively with 250 to 300 cm /h of crystalloid solutions for the rst 48 hours after admission. Patients who have borderline cardiac function or respiratory failure may require a Swann-Ganz catheter to monitor uid balance during aggressive hydration. Patients without prior diabetes mellitus may experience moderate hyperglycemia during severe pancreatitis. Hypocalcemia commonly occurs with acute pancreatitis, particularly when the attack is severe [147]. Morphine traditionally has been disfavored for acute pancreatitis because it increases the sphincter of Oddi pressure. Meperidine can be administered safely for a few days but should not be administered long term at high dose (O100 mg/3 h) because the accumulation of the metabolite normeperidine can cause agitation and, Box 5. The dose of analgesia should be monitored and titrated to achieve pain relief without somnolence or hypoventilation. For example, in a prospective, randomized trial of 60 patients who had mild to moderate pancreatitis, patients receiving nasogastric aspiration tended to resume oral feedings later and remain hospitalized longer than patients not receiving nasogastric aspiration [153]. The oxygen saturation should be maintained at 95% or higher, with supplemental oxygen administered by nasal cannulae as necessary to maintain pancreatic oxygenation and prevent pancreatic necrosis. Patients who have mild to moderate and uncomplicated pancreatitis usually are managed solely by intravenous hydration without initiating parenteral feeding, because they typically can resume oral feedings within several days when the patient has no more abdominal pain, nausea, vomiting, and abdominal distention. The diet initially consists of clear liquids and then is advanced sequentially to full liquids, soft solids, and full solids, as tolerated. Initially intake is limited to small amounts of kcal/d that are increased gradually as tolerated. Mild to moderate residual elevations of the serum amylase or lipase level are not contraindications to oral feeding, but an amylase or lipase level that is more than threefold above the normal range signals a moderately increased risk of inducing abdominal pain with refeeding [156]. These patients, however, particularly benet from nutritional supplementation for tissue repair after tissue catabolism from pancreatic necrosis and the systemic inammatory response. Stimulation of pancreatic secretion by the presence of food in the gut only pertains to food within the gastric or duodenal lumen. In a meta-analysis of seven randomized, controlled trials, enteral nutrition resulted in signicantly fewer infectious complications (risk ratio, 0. Peritoneal lavage to remove toxic necrotic compounds no longer is recommended for severe pancreatitis. In a meta-analysis of eight randomized, prospective clinical trials involving a total of 333 patients, peritoneal lavage did not reduce morbidity or mortality signicantly [162]. In contrast, a meta-analysis of eight controlled trials involving 814 patients (which did not include the aforementioned study) reported a signicantly lower mortality in patients administered prophylactic antibiotics than in untreated controls (6. Antibiotics selected for pancreatic infections should be bactericidal and produce adequate therapeutic levels within pancreatic tissue [164]. Gallstones are the most common cause because of the cholestatic eects of gestational sex hormones, particularly estrogen [169]. Alcohol is a relatively uncommon cause of pancreatitis during pregnancy, presumably because of decreased use of alcohol, a known teratogen [170]. Pregnancy does not alter the clinical presentation of acute pancreatitis signicantly. Signs include mid-abdominal tenderness, abdominal guarding, hypoactive bowel sounds, abdominal distention, and increased tympany [172]. The serum lipase level is not aected by pregnancy and retains its diagnostic usefulness during pregnancy [173]. Acute pancreatitis tends to be mild during pregnancy and to respond well to medical therapy, including intravenous uid administration, analgesia, T able C omplications of acute pancreatitis C omplication M ech anism iag nosis T reatment H ypocalcemia S equestrationof calcium S erum calcium and albuminlevels arelysevere orsymptomatic. S erum calcium level intravenouslyif unbound maybe artif actuallyd epressed (ionized) serum calcium byd ecreased bind in of levelis d ecreased. D isseminated Lipolysis bypancreatic enzymes T end ersubcutaneous, S upportive th erapyto control f at necrosis released into th e blood stream eryth ematous nod ules th at are th e acute pancreatitis converts trig lycerid es to – cm ind iameteralon monog lycerid es and toxic th e d istallimbs; pyrexia; f ree f attyacid s. S terile pancreatic necrosis elease of activated pancreatic T : f ocallackof en ancement ressive supportive care, enzymes th at cause pancreatic with injectionof intravenous especiallyintravenous h yd ration autod ig estion microvascular contrast S upplementaloxy enationas injury and necrosis necessary M onitorin of pulmonaryveinwed g e pressure bya S wann anzcath eter I nf ected pancreatic necrosis O ne th ird ormore of patients w o S epsis, persistent pyrexia and ressive percutaneous d rainag e h ave pancreatic necrosis d evelop leukocytosis.

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The meta analysis conducted by the Colorectal Cancer Collaborative Group reviewed 13 randomized trials involving 1365 patients cheap principen 250 mg fast delivery. Individual patient data for 866 patients were associated with a 35% reduction in risk of death (95% confidence interval 24 to buy principen 500mg with visa 44%) 500 mg principen visa. This was equivalent to safe 500mg principen an absolute improvement in survival of 16% at 6 and 12 months and a median survival improvement of 3. There appeared to be no difference in benefit between age groups, but fewer than 2. Quality of life scores were no different between the groups overall, but patients with abnormal scores pretreatment fared better in the chemotherapy arm. Irinotecan appeared to delay time to deterioration in performance status, weight loss, pain control and global quality of life. The Nordic gastrointestinal tumour adjuvant therapy group 114 compared early versus delayed introduction of chemotherapy for asymptomatic patients. This study demonstrated a significant improvement in symptom-free survival (10 versus 2 months, p=0. An Australian and Canadian meta analysis has failed to confirm a survival benefit for early versus delayed chemotherapy. One problem in interpreting the literature with respect to both intra-arterial and systemic chemotherapy is that although survival benefits have been demonstrated the principal determinants of enhanced survival are poorly understood. A treatment that lowered the odds of failure to respond by 50% would decrease the odds of death by Surgical Management of hepatobiliary and pancreatic disorders 218 6%. It is possible that delay in progression rather than objective response is a better surrogate marker for survival. Agents, regimens and results 5 Fluorouracil this has been the principal agent used to treat colorectal carcinoma for the past 40 years. Folinic acid (calcium folinate or leucovorin) increases intracellular levels of 5-10-methylene tetrahydrofolate. Infusion schedules tend to be associated with higher rates of cutaneous toxicity including plantarpalmar erythema (hand-foot syndrome). These studies have found increased response, decreased toxicity but no survival benefit for this strategy. It does this by creating a single strand break through which the intact strand can pass, and then by resealing the strand break. Irinotecan has been demonstrated to enhance survival compared with supportive care (9. Both trials found statistically significant advantages for irinotecan in overall survival (p= 0. The Mayo regimen exhibited increased mucositis and febrile neutropenia compared with the other treatments. Although not strictly comparable, these studies consistently demonstrate survival times that are two to three times greater than the 5-month survival observed in the supportive care arms of the Scheithauer and Beretta studies (Table 8. Oxaliplatin has low intrinsic activity against colorectal cancer, with response rates as a single agent of approximately 10%. There were significantly increased rates of neutropenia, diarrhoea and the typical cold-exacerbated neuropathy of oxaliplatin, but there was no overall difference in quality of life. Recent studies from both France and the United States 138, 139, 140 have demonstrated that between 10 and possibly 33% of patients with colorectal liver metastases, previously deemed inoperable by experienced liver surgeons, can be resected after chemotherapy using oxaliplatin. Long-term survival for these patients following hepatectomy is virtually identical to those patients who were deemed resectable at the outset. If these data are correct, resectability rates for patients with colorectal liver metastases might rise from the current rate of 10% of all patients with disease confined to the liver to possibly over 30%. A 3weekly schedule is possible with this agent due to uptake and retention within cells by the reduced folate carrier system and subsequent polyglutamation by folyl polyglutamate synthetase. The development and acceptance of raltitrexed has been hampered by the determination in separate phase I studies of differing maximum tolerated doses. The best established of these agents is capecitabine, a fluoropyrimidine carbamate prodrug. Trimetrexate enters cells by passive diffusion and inhibits dihydrofolate reductase. Which combination to use Currently there is no consensus as to which of the available agents or combinations appears to confer a substantial advantage. The prescription for any given patient may depend on ease of administration, age and performance status. While no difference was seen in the survival the trial suggests that oxaliplatin may remain active after irinotecan failure, rather than vice versa. Key points • Cryotherapy and other imaging-controlled ablative techniques can be associated with longterm survival in patients with unresectable disease. World J Surg 1998; 22:268–77 Non-resectional treatment of colorectal cancer 225 4. Percutaneous ethanol injection therapy of hepatocellular carcinoma: analysis of 77 patients. Percutaneous ethanol injection in the treatment of hepatocellular carcinoma in cirrhosis. Cryostatic congelation: a system for producing a limited controlled region of cooling or freezing of biological tissues. The role of intracellular freezing in the death of cells cooled at supraoptimal rates.

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In cats 250mg principen overnight delivery, oral cholecystography has been performed using iobenzamic acid at a dosage of 50 mg/kg and iodopate at a dosage of 150 mg/kg discount principen 250mg on line. Intravenous cholecystography has been performed in dogs using iodipamide at a dosage of 0 250mg principen. The gallbladder is monitored as it is filled with contrast material purchase 500mg principen with visa, and filling is continued until the contrast flows into the common bile duct and reaches the duodenum. Aspiration of the contrast and bile is performed before the needle is removed from the gallbladder. Twenty to thirty ml of contrast usually is required for average-size dogs (11 to 25 kg). A similar technique can be used for cholangiography, in which the contrast is identified within an intrahepatic bile duct or hepatic vein as the needle is withdrawn using fluoroscopy. These techniques are of limited value and are available only at centers that have fluoroscopic equipment. An alternative to fluoroscopy is ultrasonographically guided cholecystography and is used when it is specifically indicated to assess the gallbladder and extrahepatic biliary ducts. Sincalide, a synthetic cholecystokinin, has been used to induce gallbladder emptying in order to obtain some functional information and distinguish between obstructive and nonobstructive biliary disease. Normal dogs and dogs with nonobstructive biliary disease reduce the volume of the gallbladder by 40% within 1 hour, while obstructed dogs reduced their gallbladder volume less than 20%. This approach may save you the effort, the patient the discomfort, and the owner 278 Small Animal Radiology and Ultrasonography the expense of a contrast study. Even if noncontrast radiographs were obtained several hours or a day before, they should be repeated. This is achieved by withholding all food for at least 12 hours and using laxatives or enemas or both. We do not recommend the routine use of iodine-containing, water-soluble contrast medium for this purpose. Commercially premixed products are preferred to barium powder that requires mixing with water, because the suspending agents in commercially prepared products seem to produce superior mucosal detail, more uniform passage, less artifactual aggregation and flocculation, and a more stable suspension. Furthermore, as the contrast medium passes through the intestine, the hyperosmolar ionic agents draw body fluids into the intestine. This results in a decreasing density throughout the study and systemic dehydration, which may be dangerous in an already dehydrated patient. The use of water-soluble agents has been recommended when bowel rupture is suspected because of the potential for granulomatous peritonitis caused by free barium in the abdominal cavity. Although this is a valid consideration, the possibility of misdiagnosis because of poor contrast density in cases of minimal leakage from small defects in the bowel, coupled with the opportunity to flush any leaked barium from the abdomen at laparotomy, leads us to recommend the use of barium for almost all studies. Instillation by stomach tube requires certainty that the tube is positioned in the stomach. Even in cats, the orogastric tube can be palpated to distinguish it from the trachea if care is exercised. Use of a stomach tube is superior to oral instillation, because it is common for animals to expectorate a portion of the barium as well as to inhale some of the barium if they struggle. Gastric intubation ensures that the stomach will receive a proper dose of barium so that it is adequately distended. It has been reported that the normal time for barium to reach the colon after instillation is 90 to 270 minutes in the dog and 30 to 60 minutes in the cat. At least a ventrodorsal or dorsoventral and a lateral view should be taken at each time thereafter. The ventrodorsal view is preferred because it minimizes superimposition of structures and allows better evaluation. In the normal animal, gastric contractions will be apparent and will alter the gastric shape over time. An open pylorus is rarely seen radiographically because, compared with gastric mixing, pyloric opening is relatively infrequent and of short duration. Although the length of time required for complete gastric emptying varies, a marked delay in beginning the passage of significant amounts of contrast agent from the stomach implies a pyloric outflow obstruction. These animals will usually resume normal peristalsis if left in a quiet environment for a few minutes. There is a great deal of variation in gastric emptying times among normal dogs, so most figures given are useful only as crude estimates. Although each individual dog is consistent, there is considerable variation from dog to dog. In most cases, the liquid barium will separate from the food and transit the intestines while the food remains in the stomach until it becomes liquefied. Although gastric emptying time following administration of a barium-food mixture is fairly consistent for an individual dog, a large variation is observed among dogs. The loops are smooth walled and uniformly distended, with a few constrictions representing normal peristalsis. Irregularities in the duodenum of the dog consisting of one or more crater-like lesions result from the presence of gut-associated lymphoid tissue (Fig. Radiographic findings include smooth and well-defined rectangular outpouchings of the mucosal pattern (arrows) at intervals along the course of the duodenum. If a structure appears abnormal on one film but does not remain constant in appearance on at least the same view throughout the series, it should be regarded as spurious and the study findings should be considered normal.

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The urethra was calibrated with ease generic principen 250mg free shipping, using a #26 French Van Buren urethral sound order principen 250mg mastercard. The prostate and bladder appeared normal discount principen 500mg otc, except for the presence of a left ureterocele buy cheap principen 250 mg on-line, which was incised longitudinally; a large calculus was extracted from the ureterocele. The stone was crushed with the Storz stone-crushing instrument, and the fragments were evacuated. Analysis Review the medical record Operative Report: Ureterocele to answer the following questions. Medical Record Activity 11–2 Operative report: Extracorporeal shockwave lithotripsy Terminology the terms listed in the chart come from the medical record Operative Report: Extracorporeal Shockwave Lithotripsy that follows. He now presents for the fragmenting of the remainder of the calculus and removal of the double-J stent. After induction of anesthesia, fluoroscopy was used to position the patient in the focal point of the shockwaves. Being well positioned, he was given a total of 4,000 shocks with a maximum power setting of 3. After confirming complete fragmentation via fluoroscopy, the patient was transferred to the cystoscopy suite. Medical Record Activities 343 the patient was placed in the dorsal lithotomy position and draped and prepped in the usual manner. Once the stent was visualized, it was grasped with the grasping forceps and removed as the scope was withdrawn. Analysis Review the medical record Operative Report: Extracorporeal Shockwave Lithotripsy to answer the following questions. What imaging technique was used for positioning the patient to ensure that the shockwaves would strike the calculus Recognize, pronounce, spell, and build words related to the female reproductive system. Key Terms this section introduces important female reproductive system terms and their definitions. Anatomy and Physiology 347 Anatomy and Physiology the female reproductive system is composed of internal and external organs of reproduction. The internal organs include the (1) ovaries, (2) fallopian tubes, (3) uterus, (4) vagina, and external genitalia. Included in these structures are the (5) labia minora, (6) labia majora, (7) clitoris, and (8) Bartholin glands. Anterior view Sacrum Peritoneal cavity (1) Ovary (2) Fallopian tube (3) Uterus (oviduct) Urinary bladder Rectum Pubis Urethra (7) Clitoris Cervix (5) Labia minora Anus (6) Labia majora (4) Vagina Perineum (8) Bartholin gland B. Hormones play an important role in the reproductive process, with each providing its influence at critical times during preconception, fertilization, and gestation. Female Reproductive Organs Female reproductive organs include the ovaries, fallopian tubes, uterus, and vagina. Ovaries the (1) ovaries are almond-shaped glands located in the pelvic cavity, one on each side of the uterus. Each ovary contains thousands of tiny, saclike structures called (2) graafian follicles. When an ovum matures, the (3) mature follicle moves to the surface of the ovary, ruptures, and releases the ovum, a process called ovulation. After ovulation, the empty follicle is transformed into a very different looking structure called the (4) corpus luteum, a small yellow mass that secretes estrogen and progesterone. In addition, both hormones prepare the uterus for implantation of the fertilized egg, help to maintain pregnancy, and promote growth Anatomy and Physiology 349 of the placenta. Estrogen and progesterone also play an important role in development of secondary sex characteristics. The (6) fimbriae are fingerlike projections that create wavelike currents (peristalsis) in fluid surrounding the ovary to move the ovum into the uterine tube. If the egg unites with a spermatozoon, the male reproductive cell, fertilization or conception takes place. If conception does not occur, the ovum disintegrates within 48 hours and is discharged through the vagina. Uterus and Vagina the (7) uterus contains and nourishes the embryo from the time the fertilized egg is implanted until the fetus is born. It is a muscular, hollow, inverted-pear–shaped structure located in the pelvic area between the bladder and rectum. The uterus is normally in a position of anteflexion (bent forward) and consists of three parts: the (8) fundus, the upper, rounded part; the (9) body, which is the central part; and the (10) cervix, also called the neck of the uterus or cervix uteri, the inferior constricted portion that opens into the vagina. The (11) vagina is a muscular tube that extends from the cervix to the exterior of the body. Its lining consists of folds of mucous membrane that give the organ an elastic quality. During sexual excitement, the vaginal orifice is lubricated by secretions from (12) Bartholin glands. In addition to serving as the organ of sexual intercourse and receptor of semen, the vagina discharges menstrual flow. The clitoris (see Figure 12–1), located anterior to the vaginal orifice, is composed of erectile tissue that is richly innervated with sensory endings. The clitoris is similar in structure to the penis in the male, but is smaller and has no urethra. Mammary Glands Although mammary glands (breasts) are present in both sexes, they function only in females.

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Most will stabilize or improve with development of increased collateral blood flow following institution of a program of daily exercise buy 250mg principen amex, cessation of smoking buy principen 500 mg mastercard, and weight loss purchase 500 mg principen free shipping. Ankle-brachial index is a useful preoperative tool but does not by itself determine whether someone is a candidate for revascularization order 250 mg principen with visa. Vasodilator drugs have been shown to have little benefit in the conservative management of intermittent claudication. Aspirin exerts an antiplatelet effect that will last for the life of the platelet (approximately 7-10 days). Aspirin interferes with platelet function by inhibiting the synthesis of thromboxane A2 and the subsequent production of prostaglandins. Other medical management options include lipid-lowering therapy and smoking cessation. On being subjected to exercise, the involved extremity (usually the left, which is more prone to atherosclerosis because of anatomic differences) develops relative ischemia, which gives rise to reversal of flow through the vertebral artery with consequent diminished flow to the brain. The operative procedure for treating the subclavian steal syndrome consists of delivering blood to the extremity by creating either a carotid-subclavian bypass or a subclavian-carotid transposition. Dilatation and stenting of the artery by endovascular techniques is effective as well. Ischemic rest pain or early onset of claudication after minimal exercise limits the effectiveness of stress testing as a screening procedure for occult coronary artery disease in this group of patients. Coronary angiography is invasive and therefore not used as a screening tool to assess the cardiac status of patients undergoing noncardiac surgery. Angiography is used to exactly define the anatomic abnormalities contributing the ischemia in patients who have already been evaluated with noninvasive testing. Transesophageal echocardiography is invasive and has no role in the preoperative screening of peripheral vascular patients. An electrocardiogram is useful in detecting perioperative ischemia and infarction, not in predicting them. The heart is the most common source of arterial emboli and accounts for 90% of cases. Sources include diseased valves, endocarditis, the left atrium in patients with unstable atrial arrhythmias, and mural thrombus on the wall of the left ventricle in patients with myocardial infarction. The diagnosis in this patient is clear, and therefore neither noninvasive testing nor arteriography is indicated. Embolectomy of the femoral artery can be performed under local anesthesia with minimal risk to the patient. Emboli typically lodge in 1 femoral artery; contralateral exploration is not indicated in the absence of signs or symptoms. The contralateral groin should always be prepared in case flow is not restored via simple thrombectomy, and femoral-femoral bypass is needed to provide inflow to the affected limb. Popliteal artery aneurysms are the most common peripheral arterial aneurysms and are bilateral in 53% of patients. Many patients are asymptomatic when diagnosed, but they can present with chronic limb ischemia or acute thromboembolism. All symptomatic popliteal aneurysms should undergo surgical repair with exclusion of the aneurysm (which is ligated and left in situ) combined with a surgical bypass. Because of the risk of complications, asymptomatic popliteal aneurysms greater than 2 cm should be repaired as well. Thrombolytic therapy is reserved for patients who present with acute limb ischemia to improve runoff for revascularization and decrease limb loss. Neither antiplatelet therapy nor anticoagulation therapy are useful in the management of popliteal artery aneurysms. This is confirmed by both the physical examination and the flow study findings which indicate a sharp decrease in the blood pressure below the level of the common femoral artery. Physical examination and flow studies indicate disease distal to the aortoiliac distribution. It is indicated in patients who sustain a recurrent pulmonary embolus despite adequate anticoagulant therapy or in patients with pulmonary emboli who cannot receive anticoagulants because of a contraindication (eg, bleeding ulcer, intracranial hemorrhage). It is placed in the inferior vena cava just below the renal veins and therefore would not be effective for emboli that arise cephalad to its position. Despite the hypercoagulable state seen in some patients with metastatic pancreatic cancer, anticoagulation can still be used as a first-line defense. The etiology of ischemia may be embolic or thrombotic occlusion of the mesenteric vessels or nonocclusive ischemia due to a low cardiac index or mesenteric vasospasm. While not without serious risks, angiography also offers the possibility of direct infusion of vasodilators into the mesenteric vasculature in the setting of nonocclusive ischemia. This patient, with a recent myocardial infarction and a low cardiac index, is at risk for embolism of clot from a left ventricle mural thrombus as well as low-flow mesenteric ischemia. If embolism or thrombosis is found angiographically (usually involving the superior mesenteric artery), thrombolytic therapy can be attempted in the absence of suspicion of ischemic bowel. If occlusive disease cannot be demonstrated, efforts should be made to simultaneously increase cardiac output with inotropic agents and dilate the mesenteric vascular bed by angiographic instillation of papaverine, nitrates, or calciumchannel blockers. Computed tomography is not helpful in delineating the cause of intestinal ischemia because it does not provide a sufficiently detailed image of the mesenteric vessels. Laparoscopy and/or laparotomy would be useful if ischemic bowel were suspected, although laparoscopy would not allow for adequate assessment of the visceral vessels. Flexible sigmoidoscopy, while useful in patients with ischemic colitis, has no role in the workup of mesenteric ischemia, which involves primarily the small intestine and right colon. Serum lactate is helpful in raising the suspicion of intestinal ischemia, but no absolute level should be used to decide whether or not to explore a patient. The proximal veins are not accessible due to their location and therefore cannot be adequately evaluated using the duplex ultrasound. The duplex scanning device is portable, and therefore the study is easily performed at the bedside, in a vascular laboratory, or in a radiology suite.