Anesthesia and analgesia
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Anesthesia and analgesia · Jul 2010
The effective concentration of epsilon-aminocaproic Acid for inhibition of fibrinolysis in neonatal plasma in vitro.
Pediatric patients, particularly neonates, are at high risk for bleeding complications after cardiovascular surgery because of their immature hemostatic system, small size, and the complex operations they require. Activation of intravascular fibrinolysis is one of the principle effects of cardiopulmonary bypass that causes poor postoperative hemostasis. This complication has long been recognized and treated with antifibrinolytic medications, including the lysine analog epsilon aminocaproic acid (EACA). The therapeutic plasma concentration of EACA has been scientifically determined for the adult population, but the current recommended dosage for neonates has been empirically derived from adult studies. Therefore, we investigated the appropriate concentration of EACA for neonates undergoing bypass. ⋯ Our data establish the minimal effective concentration of EACA necessary to completely prevent fibrinolysis in neonatal blood in vitro. This concentration is significantly less than that targeted by current dosing schemes, indicating that neonates are possibly being exposed to greater levels of EACA than is clinically necessary.
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Anesthesia and analgesia · Jul 2010
ReviewResidual neuromuscular block: lessons unlearned. Part II: methods to reduce the risk of residual weakness.
The aim of the second part of this review is to examine optimal neuromuscular management strategies that can be used by clinicians to reduce the risk of residual paralysis in the early postoperative period. Current evidence has demonstrated that frequently used clinical tests of neuromuscular function (such as head lift or hand grip) cannot reliably exclude the presence of residual paralysis. When qualitative (visual or tactile) neuromuscular monitoring is used (train-of-four [TOF], double-burst, or tetanic stimulation patterns), clinicians often are unable to detect fade when TOF ratios are between 0.6 and 1.0. ⋯ The use of intermediate-acting neuromuscular blocking drugs (NMBDs) can reduce, but do not eliminate, the risk of residual paralysis when compared with long-acting NMBDs. In addition, complete recovery of neuromuscular function is more likely when anticholinesterases are administered early (>15-20 minutes before tracheal extubation) and at a shallower depth of block (TOF count of 4). Finally, the recent development of rapid-onset, short-acting NMBDs and selective neuromuscular reversal drugs that can effectively antagonize deep levels of blockade may provide clinicians with novel pharmacologic approaches for the prevention of postoperative residual weakness and its associated complications.
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Anesthesia and analgesia · Jul 2010
Comparative StudyHigh-resolution solid-state manometry of the upper and lower esophageal sphincters during anesthesia induction: a comparison between obese and non-obese patients.
The prevalence of obesity has increased dramatically in recent decades. The gastrointestinal changes associated with obesity have clinical significance for the anesthesiologist in the perioperative period. The lower esophageal sphincter and the upper esophageal sphincter play a central role in preventing regurgitation and aspiration. The effects of increased intra-abdominal pressure during anesthesia on the lower esophageal sphincter and the upper esophageal sphincter in obese patients are unknown. In the present study we evaluated, with high-resolution solid-state manometry, the upper esophageal sphincter, lower esophageal sphincter, and barrier pressure (BrP) (lower esophageal pressure--gastric pressure) in obese patients during anesthesia induction and compared them with pressures in non-obese patients. ⋯ Lower esophageal sphincter and BrPs decreased in both obese and non-obese patients during anesthesia induction, but were significantly lower in obese patients. Although the BrP was significantly lower, it remained positive in all patients.
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Anesthesia and analgesia · Jul 2010
Skin collagen synthesis is depressed in patients with severe sepsis.
Skin is an essential barrier in maintaining a stable internal environment. Adequate regenerative capacity is crucial to overcome the homeostatic challenges caused by a septic insult. In sepsis, coagulation and inflammation are activated to restore homeostasis, but it is not known whether sepsis also alters tissue regeneration processes such as skin collagen synthesis. ⋯ Skin collagen synthesis is depressed during severe sepsis and is followed by a compensatory response 3 and 6 months after the onset of sepsis.