By Q. Frillock. Eastern Kentucky University.
This large cheap 40mg propranolol overnight delivery cardiovascular disease 1 cause of death, acute generic 80mg propranolol amex cardiovascular system drawing, left external capsule hema- case emphasizes the importance of looking for the cause of a hem- toma evolves from a ﬂuid collection containing deoxyhemoglobin orrhage cheap 80mg propranolol visa arteries in the wrist, as the post-contrast scan reveals the associated enhancing (white asterisk, with low signal intensity on T2-weighted scans), to metastasis (black arrows). One arachnoid hemorrhage due either to a time delay (a few key to the recognition of parenchymal hemorrhage, not days) between the hemorrhage and imaging or the small discussed in detail, is the presence of edema surrounding quantity of blood present. Depending on the amount of blood however not speciﬁc for subarachnoid hemorrhage, and 1 Brain 29 of methemoglobin. By 3 days following presentation, high signal intensity is commonly seen on T1-weighted scans, a ﬁnding that typically persists for days to weeks. High signal intensity Superﬁcial Siderosis on both T1- and T2-weighted scans is consistent with extracellular methemoglobin, in this late subacute hypertensive hemorrhage. The cause is recurrent subarachnoid hemorrhage, typi- cally due to a hemorrhagic neoplasm, ruptured aneurysm, or vascular malformation that has bled. The surface of the can be seen in any disease process that leads to a subtle cerebellum is the most common site (Fig. Meningitis symptoms occur rarely, and only when there is substan- produces this appearance, with administration of 100% O2 tial deposition of hemosiderin. Possible symptoms include in anesthetized ventilated patients another known cause. Any sequence that improves the sensitivity to speciﬁc for acute subarachnoid hemorrhage (Fig. On initial inspection, the T2-weighted scan appears normal (other than a small external capsule chronic lacunar infarct). There are three com- mon locations (given in order from the most to the least common, which also parallels the degree of severity of the injury from least to most): the gray–white matter junc- tion, the corpus callosum (splenium), and the brainstem (Fig. Most commonly these involve the frontal cerebellar folia, due to superﬁcial hemosiderin deposition from re- lobe. Suscep- tibility weighted imaging oﬀers a further improvement in sensitivity to T2* eﬀects, and in cases with hemorrhage ■ Trauma will demonstrate more extensive injury. A cortical contusion is simply a bruise of This injury and the subsequently described injury of the the brain’s surface. The inferofrontal and anteroinferior brainstem are usually not seen in isolation but with ex- temporal portions of these two lobes of the brain are par- tensive shear injury at the gray–white matter junction. The term “coup” is used to the brainstem, lesions are seen most often in the pons and reference an injury that lies directly beneath the area of the dorsolateral midbrain. The term “contrecoup” is used for an injury that very poor prognosis, often with a fatal outcome. High veloc- ity contusion injuries are illustrated in two dif- ferent patients, showing characteristic areas of the brain involved. In the ﬁrst, there is a large hemorrhagic contusion, with the area of hem- orrhage surrounded by low density (edema), overlying the right petrous apex. In the second patient, low-density regions are noted in the low frontal lobes bilaterally, cor- responding to nonhemorrhagic parenchymal contusions. Encephalomalacia, with both gliosis and cystic changes, will be seen in areas of prior contusion. Epidural Hematoma The dura is the periosteum of the inner table, and is strongly adherent to the skull. An epidural hematoma accumulates between the inner table of the skull and the dura, and is typically due to a skull fracture with lac- eration of a blood vessel. The most common location is temporal/parietal, due to laceration of the middle men- ingeal artery. Less common are posterior fossa lesions, due to an occipital skull fracture with secondary lacer- ation of the transverse sinus. In 50% of cases there will be an intervening lucid interval after the initial trauma, with subsequent rapid progressive deterioration. The imaging appearance is that of a biconvex, elliptical ﬂuid collection, which can cross the midline (falx) and the ten- torium, with the venous sinuses displaced away from the skull (Fig. Note also the extracranial soft tissue brain injuries, as well as subacute hemorrhage. Edema (high signal intensity) of the splenium of the corpus callosum reveals edema therein and petechial hemorrhage (low signal intensity) are seen on T2- (black arrow), a less frequent and more clinically significant in- weighted scans at the gray–white matter junction of the fron- jury. A large, extra-axial, high-density ﬂuid collection (acute hemorrhage) is seen on the right, overlying the temporal and parietal lobes (part 1). On the image win- dowed for bone, an underlying, mini- mally displaced, skull fracture (small white arrow) is noted. In a second pa- tient (part 2), a smaller epidural he- matoma is noted overlying the right frontal lobe (large black arrow). With some chronic subdural hematomas there may be suﬃcient resorption of blood products to make diﬀerentiation from a hygroma, on the Subdural Hematoma basis of signal intensity, diﬃcult. Findings include skull fractures, sub- intracellular methemoglobin to extracellular methemo- dural hematomas, and contusions. Otherwise, children in whom this entity is tually remove the blood products therein. Territorial infarcts and/or global hypoxic hypointense with brain on T1-weighted images, with high injury may also be present. A subdural hygroma, T2*-weighted scans is in part for the detection of chronic 1 Brain 33 Fig. A small subdural hematoma is seen on the right, with a much larger subdural hematoma on the left. The large subdural hema- toma exhibits many adhesions, best seen on the T2*-weighted gradient echo scan, important information to communicate to the neurosurgeon since drainage will likely require lysis of these adhesions. The ipsilateral ventricle will be compressed and displaced toward the Penetrating Injuries midline. The herniated anterior cerebral artery In addition to the defecThat the entry site, there may be can also be compressed against the free margin of the extensive skull fractures. The location of metal fragments falx, and thus occluded with subsequent infarction of the from the bullet will be readily evident. Parenchymal hemorrhage is almost always pres- Descending transtentorial herniation is the second ent and subdural hematomas common. The uncus of the temporal lobe will be ■ Herniation displaced medially and encroach upon the suprasellar cistern. On imaging, both the ipsilateral ambient cistern Subfalcine herniation is the most common brain hernia- (which lies lateral to the midbrain) and lateral portion tion, and is caused by a supratentorial mass on one side of the prepontine cistern may be widened. Herniation of brain mass eﬀect, the uncus and hippocampus can both herniate occurs across the midline under the inferior or “free” through the tentorial incisura. There are subdural hematomas of four diﬀer- ent time frames (numbered 1 to 4, each with a characteristic signal intensity) in this infant, a pathognomic appearance for nonaccidental trauma. In addition, there is mild cerebral atrophy on the right, with the subdural hematomas causing mass eﬀect on the left, re- ﬂected by obliteration of cerebral sulci together with the left atrium of the lat- eral ventricle.
Usual (less with terizidone) and include headache order propranolol 80mg with mastercard juxta glomerular capillaries, tremors cheap propranolol 40mg fast delivery cardiovascular medications, in- adult dose is 150 mg/day buy cheap propranolol 40mg line arteries pump blood away from the heart. Addition of pyridoxine (50 mg/ patients may have higher incidence of Stevens–Johnson 250 mg of cycloserine and terizidone is recommended) syndrome. Adverse effects range from to treat drug-susceptible or drug-resistant tuberculosis. This long interval renders moxifloxacin and gatifloxacin have equal potency, the lat- feasible the directly observed administration of rifampicin ter is not favoured in those with diabetes mellitus because which the above regimens require. It causes gas- lones have some efficacy against ofloxacin-resistant strains trointestinal symptoms. Commonly observed adverse effects include gastrointestinal upset, hepatic dysfunction, hypothyroidism; it should be administered cautiously in Other bacterial infections patients with cardiac and renal insufficiency because of Burns. Substantial absorption can occur from any raw Agents with unclear efficacy (not surface and use of aminoglycoside preparations, e. Use of systemic antibiotics for days 4 to 14 in patients with large burns has been Clofazimine. Usual adult dose is 600 mg twice a day for of a significant rise in the prevalence of antibiotic 4–6 weeks and subsequently the dose is reduced to resistance. However assiduous the skin preparation for orthopaedic operations or thigh amputations, this will not kill or re- Leprosy move all the spores. Surgery done for vascular insufficiency where tissue oxygenation may be poor is likely to be Effective treatment of leprosy is complex and requires followed by infection. Problems of gens) may occur; prophylaxis with benzylpenicillin or resistant leprosy now require that multiple drug therapy metronidazole is used. Mild streptococcal/staphylococ- Dapsone is a bacteriostatic sulphone (related to sulphona- cal cases will usually respond to flucloxacillin, although mides, acting by the same mechanism; see p. It has more clinically severe infections may require the addition long been the standard drug for all forms of leprosy. Occasionally ular and inadequate duration of treatment with a single the infection may progress to a rapidly spreading infection drug has allowed the emergence of primary and secondary of the tissues, with necrosis of the overlying skin (so-called resistance to become a major problem. Dapsone is also ‘necrotising fasciitis’); to halt its spread requires urgent 209 Section | 3 | Infection and inflammation surgical resection of all non-viable tissues, and addition of These bacteria can be resistant to all conventional antimi- clindamycin to the antibiotic regimen is recommended. Systemic antibiotic therapy is necessary at least otics have been recommended and previously outdated for several days in dirty wounds, and in penetrating agents have been resurrected for treatment of infections with wounds of body cavities. Many reported strains produce a white-cell toxin, the Panton–Valentine leucocidin, and Bites from humans and other mammals are common and affected patients may suffer cutaneous abscesses and involve the inoculation of the rich bacterial flora of the necrotizing fasciitis and pneumonia. Secondary infection is frequent treatment regimens include antibiotics active at (up to 80% cat bites become infected) and may involve the ribosome to reduce toxin production – Pasteurella multocida which can cause rapidly spreading especially linezolid and clindamycin – and topical cellulitis and is resistant to flucloxacillin and erythromycin. Antibiotic prophylaxis reduces wound infection risks in bites of the hand and those made by humans or cats, and co-amoxiclav is considered the Actinomycosis. The anaerobe Actinomyces israelii is sensi- best choice; microbiological advice should be sought for tive to several drugs, but not to metronidazole, and drug patients allergic to penicillin. High Abscesses and infections in serous cavities are treated doses of benzylpenicillin or amoxicillin are given for sev- according to the antimicrobial sensitivity of the organism eral weeks; the infections are often mixed with other anaer- concerned, but require high doses because of poor penetra- obic bacteria, so metronidazole is often given in addition to tion. Aspiration or surgical drainage of such collections of ensure activity against all components of the mixture. Co- pus shortens the period of illness, and antibiotic therapy amoxiclav may be a convenient alternative. Surgery is likely may on occasion be avoided for smaller abscesses after to be needed. To be maximally effective against Leptos- Acne is in part caused and exacerbated by infection with pira, start chemotherapy within 4 days of the onset of Propionibacterium acnes. Benzylpenicillin is recommended for severe (such as doxycycline) produce modest benefit when com- disease, and cefotaxime is an alternative; a Herxheimer re- bined with topical therapy with benzoyl peroxide. General ventilator-associated pneumonia, surgical wound infection, supportive management is important, including attention intravenous catheter-associated bacteraemia, meningitis fol- to fluid balance and observation for signs of hepatic, renal lowing neurosurgery, and infection of prosthetic devices or cardiac failure. Keeping the skin covered and use of insect field Group A beta-haemolytic streptococcus, but a number repellents are probably effective to prevent tick bites; tick of antibiotic-resistant pathogens are also commonly in- removal shortly after attachment (within 24 h) should pre- volved. A single dose of doxycycline 200 mg within lems, especially because the infections often present in 72 h of a recognised tick bite is 87% effective as prophy- patients with multiple pre-existing pathologies, including laxis, but should be used only in high-risk areas (expert ad- liver and renal impairment. Bacterial septic arthritis in meningococcal septicaemia in decisions: management of skin and adults. Skin and soft-tissue Diagnosis and management of protocols-adults (accessed November infections caused by methicillin- prosthetic joint infection. Available online at: http:// infection in adults: a national clinical (accessed November 2011). Available online at: investigating and treating a wide range management of acute cutaneous http://jac. Guidelines for the programmatic meningococcal disease in children and van de Beek, D. The earlier that treatment is given, therefore, the better metabolism of host cells. In the past 15 years, ten the consequence of reactivation of latent virus in the identification of the molecular differences between body. Patients whose immune systems are compromised viral and human metabolism has led to the may suffer particularly severe illness. Viruses are capable development of many effective antiviral agents; four of developing resistance to antimicrobial drugs, with simi- were available in 1990, now there are over 40. An overview of drugs that • Fungal infections range from inconvenient skin have proved effective against virus diseases appears in conditions to life-threatening systemic diseases; the Table 15. Drug resistance is an increasing problem and differs with geographical Aciclovir location, and species of plasmodium. Aciclovir (t 3 h) is a nucleoside analogue that is selectively ½ • Helminthic infestations cause considerable morbidity. Phos- Thedrugsthatareeffectiveagainsttheseorganismsare phorylated aciclovir inhibits viral replication by acting as summarised. About 20% is absorbed vitro, which was the basis for the boom of antibiotics in the 1950s, was from the gut, but this is sufficient for oral systemic treat- not successful for antivirals... Nature These differences are taken into account in dosing for viral Medicine 10:1177–1185. For oral and topical use the drug is given five times • Ocular keratitis (topical treatment with ophthalmic daily. It can be given twice daily orally for suppressive ointment is standard, oral treatment is also effective). The ophthalmic produce profound suppression of viral replication in ointment causes a mild transient stinging sensation and a many patients and allow useful reconstitution of diffuse superficial punctate keratopathy which clears when the immune system, measured by a fall in the plasma the drug is stopped. It is used for treating herpes zoster infec- either prevent binding of the drug to the active site tions and herpes simplex infections of the skin and mucous of the protease or reverse transcriptase enzymes, or membranes.
Potassium phosphate is a suit- Acidosis able alternative with concomitant hypophosphate- Hypertonicity mia (diabetic ketoacidosis) order propranolol 80mg free shipping heart disease congestive heart failure. Rhabdomyolysis Excessive exercise Periodic paralysis Anesthetic Considerations Succinylcholine Hypokalemia is a common preoperative fnding cheap propranolol online visa capillaries greatest surface area. Decreased renal potassium excretion The decision to proceed with elective surgery is Renal failure + Decreased mineralocorticoid activity and impaired Na+ ofen based on lower plasma [K ] limits somewhere reabsorption between 3 and 3 order propranolol 80mg visa blood vessels names. The decision, how- Acquired immunodeficiency syndrome ever, should also be based on the rate at which the Potassium-sparing diuretics hypokalemia developed as well as the presence or Spironolactone absence of secondary organ dysfunction. The latter may not apply to patients Nonsteroidal antiinflammatory drugs receiving digoxin, who may be at increased risk of Pentamidine Trimethoprim developing digoxin toxicity from the hypokalemia; plasma [K+] values above 4 mEq/L are desirable in Enhanced Cl− reabsorption such patients. Intravenous Increased potassium intake potassium should be given if atrial or ventricular Salt substitutes arrhythmias develop. Hyperkalemia rarely occurs in nor- mal individuals because of the kidney’s capability A similar release of potassium from platelets occurs when the platelet count exceeds 1,000,000 × 10 /L. When potassium intake is increased slowly, the kidneys can excrete as much as 500 mEq of K+ per day. The sympathetic Hyperkalemia due to Extracellular nervous system and insulin secretion also play Movement of Potassium important roles in preventing acute increases in Movement of K+ out of cells can be seen with aci- plasma [K+] following acquired potassium loads. Although lality, digitalis overdoses, during episodes of hyper- usually asymptomatic, these patients develop hyper- kalemic periodic paralysis, and with administration kalemia when they increase their potassium intake of succinylcholine, β2-adrenergic blockers, and argi- or when given potassium-sparing diuretics. The average increase in plasma also ofen have varying degrees of Na+ wasting and a [K+] of 0. Drugs interfering with the renin–aldosterone β2-Adrenergic blockade accentuates the increase system have the potential to cause hyperkalemia, in plasma [K+] that occurs following exercise. Large doses of heparin can a performance-enhancing supplement by athletes, interfere with aldosterone secretion. The potassium- can cause hyperkalemia as the cationic arginine ions sparing diuretic spironolactone directly antagonizes enter cells and potassium ions move out to maintain aldosterone activity at the kidneys. Decreased renal excretion of potassium can also occur as a result of an intrinsic or acquired Hyperkalemia due to defect in the distal nephron’s ability to secrete Decreased Renal Excretion potassium. Such defects may occur even in the of Potassium presence of normal renal function and are char- acteristically unresponsive to mineralocorticoid Decreased renal excretion of potassium can result therapy. The kidneys of patients with pseudohy- from (1) marked reductions in glomerular fltration, poaldosteronism display an intrinsic resistance to (2) decreased aldosterone activity, or (3) a defect in aldosterone. Increased Potassium Intake Hyperkalemia due to decreased aldosterone Increased potassium loads rarely cause hyperka- activity can result from a primary defect in adre- lemia in normal individuals unless large amounts nal hormone synthesis or a defect in the renin– are given rapidly and intravenously. Patients with primary adrenal mia, however, may be seen when potassium intake insufciency (Addison’s disease) and those with is increased in patients receiving β blockers or isolated 21-hydroxylase adrenal enzyme defciency in patients with renal impairment. Treatment is directed to reversal of cardiac Clinical Manifestations manifestations and skeletal muscle weakness, and of Hyperkalemia to restoration of normal plasma [K ]. Drugs contributing to hyperkalemia should muscle membrane, eventually resulting in paralysis. Contrac- mote cellular uptake of potassium and can decrease tility may be relatively well preserved until late in the plasma [K+] within 15 min. Hypocalcemia, cellular uptake of potassium and may be useful in hyponatremia, and acidosis accentuate the cardiac acute hyperkalemia associated with massive transfu- efects of hyperkalemia. An intravenous infusion of glu- tion, and bone metabolism, and abnormalities in cose and insulin (30–50 g of glucose with 10 units of calcium balance can result in profound physiologi- insulin) is also efective in promoting cellular uptake cal derangements. In the absence of renal function, Intestinal absorption of calcium occurs primar- elimination of excess potassium can be accom- ily in the proximal small bowel but is variable. The kidneys are responsible for most cal- Dialysis is indicated in symptomatic patients cium excretion. Hemodialy- 100 mg/d but may vary from as low as 50 mg/d to sis is faster and more efective than peritoneal dialy- more than 300 mg/d. Calcium reabsorption paral- removal with hemodialysis approaches 50 mEq/h, lels that of sodium in the proximal renal tubules and compared with 10–15 mEq/h for peritoneal dialysis. Succinylcholine Plasma Calcium Concentration is contraindicated, as is the use of any potassium- containing intravenous solutions such as lactated The normal plasma calcium concentration is Ringer’s injection. Approximately respiratory acidosis is critical to prevent further 50% is in the free ionized form, 40% is protein increases in plasma [K+]. Ventilation should be con- bound (mainly to albumin), and 10% is complexed trolled under general anesthesia, and mild hyper- with anions such as citrate and amino acids. Changes in plasma albumin concentration afect total but not ionized calcium Disorders of Calcium Balance concentrations: for each increase or decrease of 1 g/dL in albumin, the total plasma calcium con- Although 98% of total body calcium is in bone, centration increases or decreases approximately maintenance of a normal extracellular calcium con- 0. Calcium ions Changes in plasma pH directly afect the degree are involved in nearly all essential biological func- of protein binding and thus ionized calcium con- tions, including muscle contraction, the release of centration. In contrast, calcium normally leaves the Lithium extracellular compartment by (1) deposition into bone, (2) urinary excretion, (3) secretion into the intestinal tract, and (4) sweat formation. Hypercalcemia due to increased turnover metabolic conversion of (primarily endogenous) of calcium from bone can also be encountered in cholecalciferol, frst by the liver to 25-cholecalcif- patients with benign conditions such as Paget’s erol and then by the kidneys to 1,25-dihydroxycho- disease and chronic immobilization. Calcitonin is a polypeptide hormone that is secreted by parafollicular cells in the thyroid gland. Clinical Manifestations Its secretion is stimulated by hypercalcemia and of Hypercalcemia inhibited by hypocalcemia. Calcitonin inhibits Hypercalcemia ofen produces anorexia, nausea, bone reabsorption and increases urinary calcium vomiting, weakness, and polyuria. Hypertension is ofen present initially before Anesthetic Considerations hypovolemia supervenes. The most efective initial treatment utilized, especially for patients with cardiac impair- is rehydration followed by a brisk diuresis (urinary ment. Serial measurements of [K+] and [Mg ] 2+ output 200–300 mL/h) utilizing intravenous saline are helpful in detecting iatrogenic hypokalemia infusion and a loop diuretic to accelerate calcium and hypomagnesemia. Ventilation should dration may aggravate the hypercalcemia by exac- be controlled under general anesthesia. Renal loss of potassium should be avoided so as to not worsen the elevated and magnesium usually occurs during diuresis, and plasma [Ca2+]. Additional therapy available, the total calcium concentration must be with a bisphosphonate or calcitonin may be required corrected for decreases in plasma albumin concen- to further lower the serum calcium level. The causes of hypocalcemia are hypercalcemia (>15 mg/dL) usually requires addi- listed in Table 49–12. Dialysis is very efective in Hypoparathyroidism correcting severe hypercalcemia and may be neces- Pseudohypoparathyroidism sary in the presence of kidney or heart failure. Addi- tional treatment depends on the underlying cause of Vitamin D deficiency the hypercalcemia and may include glucocorticoids Nutritional Malabsorption in the setting of vitamin D–induced hypercalcemia Postsurgical (gastrectomy, short bowel) such as granulomatous disease states. Inflammatory bowel disease It is necessary to look for the underlying eti- Altered vitamin D metabolism ology and direct appropriate treatment toward the Hyperphosphatemia cause of the hypercalcemia once the initial threat of hypercalcemia has been removed.
With the patient’s head pathetic system in a patient’s pain and possibly also extended 40 mg propranolol for sale cardiovascular system video lecture, a 4- to 5-cm 22-gauge needle is inserted provide long-term pain relief generic propranolol 80mg free shipping blood vessels for grade 6. The most common at the medial edge of the sternocleidomastoid mus- indications for sympathetic nerve blocks include cle just below the level of the cricoid cartilage at the refex sympathetic dystrophy best buy for propranolol cardiovascular accident, visceral pain, acute level of the transverse process of C6 (Chassaignac’s herpetic neuralgia, postherpetic pain, and periph- tubercle) or C7 (3–5 cm above the clavicle). Isolated sympathetic blockade operative hand should be used to retract the muscle to a region is characterized by loss of sympathetic together with the carotid sheath prior to needle tone, as evidenced by increased cutaneous blood insertion. The needle is advanced to the transverse fow and cutaneous temperature, and by unaltered process and withdrawn 2–3 mm prior to injection. Other tests include loss of the Aspiration must be carried out in two planes before skin conductance (sympathogalvanic refex) and a 1-mL test dose is used to exclude unintentional sweat response (ninhydrin, cobalt blue, or starch intravascular injection into the vertebral or subcla- tests) following a painful stimulus. A total of 5–10 mL of local anesthetic may Cervicothoracic (Stellate) Block be injected. Indications formed under fuoroscopy, ultrasound may also be This block is ofen used for patients with head, neck, used to visualize the anatomy and decrease the risk arm, and upper chest pain. Injection of lowed promptly by an increase in the skin tempera- larger volumes of anesthetic ofen extends the block ture of the ipsilateral arm and the onset of Horner’s to the T5 ganglia. The latter consists of ipsilateral ptosis, for vasospastic disorders of the upper extremity. Sympathetic innervation of the head, neck, and most of the arm is derived from four cervical gan- D. The latter In addition to intravascular and subarach- 20 usually represents a fusion of the lower cervical and noid injection, other complications of stellate frst thoracic ganglia. Other complications may to blockade of the recurrent laryngeal nerve, and, include hypotension and possible injury to the azy- rarely, osteomyelitis or mediastinitis following gos vein on the right or to the hemiazygos vein and esophageal puncture, particularly if a lef-sided the thoracic duct on the lef. The posterior approach may have If a patient’s pain lessens afer a splanch- the highest incidence of pneumothorax. In addition, if the patient obtained pain relief from the initial block, he or she may subse- The thoracic sympathetic ganglia lie just lateral to quently beneft from radiofrequency ablation of the the vertebral bodies and anterior to the spinal nerve splanchnic nerves at T11 and T12, with potentially roots, but this block is generally not used because of longer duration of analgesia. T ree groups of splanchnic nerves (greater, lesser, and least) arise from the lower seven thoracic sym- pathetic ganglia on each side and descend alongside Celiac Plexus Block the vertebral bodies to communicate with the celiac A. Although similar to celiac plexus block, the A celiac plexus block is indicated for patients with splanchnic nerve block may be preferred because it pain arising from the abdominal viscera, particu- is less likely to block the lumbar sympathetic chain larly intraabdominal cancers. Anatomy line at the lower end of the T11 spinous process, The celiac ganglia vary in number (1–5), form, and and advanced under fuoroscopic guidance to the position. Ten milliliters of local the body of L1, posterior to the vena cava on the anesthetic is injected on each side. The needle should right, just lateral to the aorta on the lef, and poste- maintain contact with the vertebral body at all times rior to the pancreas. Technique injection into the vena cava is more likely to produce The patient is placed in a prone position and a 15-cm a severe systemic reaction than accidental intraaor- 22-gauge needle is used to inject 15–20 mL of local tic injection. Under fuoroscopic guid- include pneumothorax, retroperitoneal hemor- ance, each needle is inserted 7–8 cm from the mid- rhage, injury to the kidneys or pancreas, sexual dys- line at the inferior edge of the spinous process of L1. Back pain is in the lateral radiographic view and close to the mid- another common side efect of a celiac plexus block. Indications aorta at a level between the celiac and superior mes- Lumbar sympathetic block may be indicated for enteric arteries. The lumbar sympathetic chain ganglia The most common complication is postural hypo- are in a more anteromedial position to the vertebral tension, from block of the visceral sympathetic bodies than the thoracic ganglia, and are anterior innervation and resultant vasodilation. The lumbar chain is son, patients should be adequately hydrated intrave- usually posterior to the vena cava on the right but is nously prior to this block. The supe- 7 cm 10 cm rior hypogastric plexus usually lies just to the lef of the midline at the L5 vertebral body and beneath the bifurcation of the aorta. The fbers of this plexus divide into lef and right branches and descend to the pelvic organs via the lef and right inferior hypo- L2 gastric and pelvic plexuses. The inferior hypogastric plexus additionally receives preganglionic parasym- pathetic fbers from the S2–S4 spinal nerve roots. Technique Inferior vena cava The patient is positioned prone, and a 15-cm needle Sympathetic ganglia is inserted approximately 7 cm lateral to the L4–L5 spinal interspace. Technique vertebral disc between L5 and S1 and within 1 cm A single-needle technique at the L3 level on either of the vertebral bodies in the anteroposterior view. The nous process and is directed above or just lateral to superior hypogastric plexus block may also be per- the transverse process of the vertebrae (depending formed using a transdiscal approach, though there is on the distance from the midline). Complications include intravascular injection into the vena cava, aorta, or lumbar vessels and somatic Ganglion Impar Block nerve block of the lumbar plexus. Indications Ganglion impar block is efective for patients 21 Superior Hypogastric Plexus Block with visceral or sympathetically maintained pain in the perineal area. Anatomy from the pelvis and is unresponsive to lumbar or The ganglion impar (ganglion of Walther) is the caudal epidural blocks. The two tains visceral sensory fbers that bypass the lower lowest pelvic sympathetic ganglia ofen fuse form- spinal cord. Tis block is usually appropriate for ing one ganglion in the midline just anterior to the patients with cancer of the cervix, uterus, bladder, coccyx. Tis procedure can be facilitated with given within 2 weeks of pain onset but appear to be fuoroscopy or ultrasound. Radiofrequency ablation, of little beneft in the absence of neural compres- or in some cases a neurolytic injection, may provide sion or irritation. Long-term studies have failed to longer duration of analgesia for this sympathetically show any persistent beneft afer 3 months, and these mediated pain. Complications The two most commonly used agents are meth- Intravascular injection and transient bowel or blad- ylprednisolone acetate (40–80 mg) and triamcino- der dysfunction are possible. Dexamethasone is being involve placement of the needle through the ano- used with increased frequency due to its smaller coccygeal ligament, although these may have higher particulate size (smaller than an erythrocyte). Intravascular injection of steroid suspension with larger particulate size may lead to embolic compli- Intravenous Regional Block cations. The steroid may be injected with diluent A Bier block (see Chapter 46) utilizing local anes- (saline) or local anesthetic in volumes of 6–10 mL or thetic solution with or without adjuvants can be 10–20 mL for lumbar and caudal injections, respec- used to interrupt sympathetic innervation to an tively. Injection of on the extremity, which is then elevated and exsan- local anesthetic along with the steroid can be help- guinated using an Esmarch bandage. The tourniquet ful if the patient has signifcant muscle spasm, but it is infated to a pressure that is two times the systolic is associated with risks of intrathecal, subdural, and blood pressure, the Esmarch bandage is removed, intravascular injection. The presenting pain is ofen and the limb is checked to be certain the pulse is transiently intensifed following injection, and the absent and there is no evidence of blood fow. The local anesthetic provides immediate pain relief until solution is then injected and usually lef in place the steroidal antiinfammatory efects take place, for at least 30 min, afer which the tourniquet is usually within 12–48 h. Premature release of the tourniquet may result in a single injection is given if complete pain relief is seizure, hypotension, arrhythmia, edema, diarrhea, achieved.