Since the 1920s, fishermen have used crabpots to trap these crustaceans. The pots are designed only to catch larger animals, allowing the younger crab to escape and continue to grow. We prepare this seafood delicacy by boiling or steaming. Once the claws are removed, you can get at the delicate crabmeat by cracking the hard shell or carapace. The claws contain denser meat, which can be accessed by cracking them with a nutcracker. One specialty of French Quarter cuisine is stuffed crab, where the meat is removed, mixed with aromatics such as onion, bell pepper, celery and such, and then served on the shell, au gratin. Easy to eat; easy to love.
Mixed In Key Mac Os Cracked Ribs
On this day, the eve of his 53rd birthday, he was playing a mixed doubles exhibition match against his big brother, Luke. It was at the Colorado resort where Luke was finishing his first week as director of racquet sports.
Malignant HyperthermiaThe anesthetic management of MH presents a challenge to the anesthesiologist. MH is a clinical syndrome of markedly accelerated metabolism triggered primarily by volatile agents and the depolarizing agent succinylcholine. Susceptible patients may develop fever, tachycardia, hypercarbia, tachypnea, arrhythmias,hypoxemia, profuse sweating, HTN, myoglobinuria, mixed acidosis, and muscle rigidity in response to exposure to volatile agents or succinylcholine, although cases have been reported in which there is no evident triggering agent. Late complications may include consumptive coagulopathy, acute renal failure, muscle necrosis, pulmonary edema, and neurologic sequelae. Avoiding exposure to triggering agents is a cornerstone in the management of MH-susceptible patients.
The thoracic vertebral bodies are larger than the cervical vertebral bodies and are wider in the posterior than anterior dimension, contributing to the characteristic thoracic curvature. The long and slender thoracic spinous processes, with tips that point caudally, are most sharply angled between T4 and T9, making insertion of the epidural needle in the midline more difficult in the midthoracic region. Beyond T10, they increasingly resemble those in the lumbar region. Each thoracic vertebra articulates with ribs along the dorsolateral border of its body, a feature that may help distinguish the lower thoracic and upper lumbar regions. The inferior angle of the scapula and the 12th rib are widely used in clinical practice to estimate the level of the cross the L1 spinous process (Table 16).
TABLE 16. Anatomic landmarks to identify spinous processes of T7 and T12, respectively. The imaginary line connecting the caudal-most margin of the 12th ribs is often presumed tovertebral levels.Vertebra prominens C7Root of spine of scapula T3Inferior angle of scapula T7Rib marginL1Superior aspect of iliaccrestL3, L4Posterior superior iliacspineS2The lumbar vertebrae are the largest movable segments, with thicker anterior than posterior dimensions that contribute to the characteristic lumbar curvature. The spinous processes in this region are blunt and large, with tips that point posteriorly.Anatomic variations in the lumbosacral region that may have clinical implications are not uncommon. Sacralization of the last lumbar vertebra, marked by fusion of L5 to the sacral bone, and lumbarization of S1 and S2, in which fusion is incomplete, may make numbering and identification of the correct lumbar level difficult. Although probably not of clinical significance, patients with sacralization have also been found to have a higher position of the conus medullaris, which demarcates the cone-shaped terminus of the spinal cord, than those with lumbarization or without lumbosacral transitional vertebrae. In the absence of these transitional vertebrae, the largest and most easily palpable interspace corresponds to L5 to S1.
Spinal NervesSpinal nerves are classified as mixed nerves because they contain both a sensory and a motor component and, in many cases, autonomic fibers. Each nerve forms from the fusion of dorsal (sensory) and ventral (somatic and visceral motor) nerve roots as they exit the vertebral canal distal to the dorsal root ganglia, which contain the cell bodies of sensory neurons on either side of the spinal cord and lie between the pedicles of adjacent vertebrae.In general, dorsal roots are larger and more easily blocked than ventral roots, a phenomenon that may be explained in part by the larger surface area for exposure to LAs provided by the bundled dorsal roots.At the cervical level, the first pair of spinal nerves exits between the skull and C1. Subsequent cervical nerves continue to exit above the corresponding vertebra, assuming the name of the vertebra immediately following them. However, a transition occurs between the seventh cervical and first thoracic vertebrae, where an eighth pair of cervical nerves exits; thereafter, the spinal nerves exit below the corresponding vertebra and take the name of the vertebra immediately above.The spinal nerves divide into the anterior and posterior primary rami soon after they exit the intervertebral foramina. The anterior (ventral) rami supply the ventrolateral side of the trunk, structures of the body wall, and the limbs. The posterior (dorsal) primary rami innervate specific regions of the skin that resemble horizontal bands extending from the origin of each pair of spinal nerves, called dermatomes, and the muscles of the back. Clinically, knowledge of dermatomes is essential when planning anesthetics to specific cutaneous regions (Figure 9), although anesthesia may not be conferred reliably to the underlying viscera due to a separate innervation, and there is significant overlap in spinal nerve innervation of adjacent dermatomes (Table 18).
An understanding of the physiology of nerve conduction and the pharmacology of LAs is essential for successful epidural block. Potency and duration of LAs, preferential block of sensory and motor fibers, and the anticipated duration of surgery or need for postoperative analgesia are factors that should be considered before initiating epidural block. This section covers several practical aspects of attaining effective epidural anesthesia and analgesia.Epidural solutions may contain an LA with or without an adjuvant drug. Dose, volume, and concentration, as well as site of injection, of the LA solution vary, resulting in different pharmacodynamic effects. A, B, and C nerve fibers vary in size and in the presence of a myelin sheath. A-delta and C fibers are responsible for temperature and pain transmission. B fibers are autonomic fibers. The larger A fibers (especially A-alpha fibers) are motor fibers. C fibers are unmyelinated and smallest in size. Because they lack a protective myelin sheath and diffusion barrier, they are blocked rapidly. A and B fibers are myelinated and larger in size than C fibers. B fibers are responsible for autonomic nervous system transmission. They are smaller in size than A-delta fibers, but larger than C fibers. It is widely accepted that autonomic fibers are more susceptible to LA nerve block than sensory fibers. Epidurally administered LA preferentially nerve blocks sympathetic neural function; this explains the more extensive sympathetic dermatomal block when compared with sensory and motor nerve blocks. However, Ginosar et al recently suggested that sensory function was more susceptible to block than sympathetic function. Several other studies concurred. The dose and concentration of LA used may account for the different findings in these studies. Because of their thick myelin sheath, motor fibers require much more LA and much more time before an adequate nerve block is achieved.Local anesthetics produce reversible nerve block by blocking sodium passage through the nerve membrane. When LA is injected into the epidural space, several things occur. Most of the injected LA is absorbed into the venous blood, and a large part is retained in epidural fatty tissue. The primary sites of action of an epidurally administered LA are the ventral and dorsal nerve roots that pass through the epidural space. However, based on studies using labeled LAs, LAs can cross the dura and penetrate the spinal cord, but to a lesser extent than their penetration into the spinal nerve roots. The segmental nerve roots are mixed sensory, motor, and sympathetic nerve fibers. Hence, all three types of fibers will be affected (to varying degrees).
A variety of other classes of drugs have been studied more recently to try to improve the quality of neuraxial block. In addition to several opioids (eg, fentanyl, sufentanil, and preparations of morphine); α-adrenergic agonists; cholinesterase inhibitors; semisynthetic opioid agonist-antagonists; ketamine; and midazolam have been studied, with mixed results. The administration of clonidine in the epidural space has been studied extensively. An α2-adrenergic agonist, clonidine appears to prolong the duration of action of LAs, although the mechanism remains unclear. Animal studies have shown that clonidine reduces regional spinal cord blood flow, therefore slowing the rate of drug elimination. Kroin and colleagues demonstrated that the mechanism by which clonidine prolongs the duration of a nerve block when mixed with LAs is not mediated by α-adrenoreceptors; rather, it is more likely related to the hyperpolarization-activated cation current Ih.Some of the potential benefits of the administration of clonidine in the epidural space may include the following:
Side effects that are commonly associated with epidural clonidine include dose-independent hypotension, bradycardia, sedation, and dry mouth. Combining clonidine with other agents, such as opioids, anticholinergics, opioid agonist-antagonists, and ketamine, may enhance the beneficial effects of these drugs while minimizing adverse side effects.Neostigmine, a cholinesterase inhibitor, is a more recent addition to the list of epidural additives for selective analgesia. The mechanism of action for its analgesic effect appears to be the inhibition of the breakdown of acetylcholine and the indirect stimulation of muscarinic and nicotinic receptors in the spinal cord. Although experience with epidural neostigmine is limited, it has been reported to provide postoperative pain relief without inducing respiratory depression, motor impairment, or hypotension. When combined with other opioids, clonidine, and LAs, it may provide benefits similar to clonidine without the side-effect profile of any of these drugs given alone. Observations in patients with cancer pain showed promise that its use might be associated with less nausea and vomiting than the intrathecal application. In an investigation randomizing 48 patients to receive 0, 1, 2, or 4 μg/kg of epidural neostigmine in addition to a bupivacaine spinal anesthetic for minor knee surgery, no case of intraoperative nausea or vomiting was observed, and postoperative nausea scores did not differ between groups. These results need to be corroborated by further studies before epidural neostigmine can be recommended for daily practice.Other agents, such as ketamine, tramadol, droperidol, and midazolam, have been considered for epidural administration, with mixed results. Considerable controversy surrounds the use of midazolam intrathecally. Despite multiple publications recommending its use, recent studies have demonstrated that even a single dose of intrathecal midazolam may have neurotoxic effects. Until its safety profile can be ensured in human subjects, it is not recommended for neuraxial use at this time.One agent that shows promise is the extended-release formulation of one of the oldest opioids, morphine. DepoDur, the brand name for extended-release epidural morphine, uses a drug-release delivery system called DepoFoam. DepoFoam is composed of microscopic lipid-based particles with internal vesicles that contain the active drug and slowly release it. Recent studies have demonstrated effective pain relief with relatively minor side effects for up to 48 hours when appropriately dosed. However, concerns about delayed respiratory depression have limited its clinical use in this early stage of its clinical use. 2ff7e9595c
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