Anesthesiology
-
Review
Anemia and patient blood management in hip and knee surgery: a systematic review of the literature.
A systematic search was conducted to determine the characteristics of perioperative anemia, its association with clinical outcomes, and the effects of patient blood management interventions on these outcomes in patients undergoing major orthopedic surgery. In patients undergoing total hip or knee arthroplasty and hip fracture surgery, preoperative anemia was highly prevalent, ranging from 24 +/- 9% to 44 +/- 9%, respectively. ⋯ Treatment of preoperative anemia with iron, with or without erythropoietin, and perioperative cell salvage decreased the need for blood transfusion and may contribute to improved patient outcomes. High-impact prospective studies are necessary to confirm these findings and establish firm clinical guidelines.
-
Recent clinical trials investigating the role of hyperoxia in decreasing surgical site infection have reported conflicting results. Immunologic mechanisms through which supplemental oxygen could act have not been elucidated fully. The authors sought to investigate the effects of hyperoxia on previously tested and prognostically significant innate immune parameters to uncover the potential effects of hyperoxia at the cellular level. ⋯ Hyperoxia exerts significant effects on multiple cellular and immunologic parameters, providing a potential mechanism for benefits from the use of supplemental oxygen. However, the ability to translate positive basic scientific findings to the operating suite or bedside require the existence of similar innate immune processes in vivo and the efficient transfer of oxygen to the sites where it may be used.
-
Comparative Study
Dexmedetomidine in the care of critically ill patients from 2001 to 2007: an observational cohort study.
Dexmedetomidine is a novel sedative agent that causes anxiolysis without respiratory depression in critically ill patients. We sought to examine patient and hospital variation in dexmedetomidine use and adoption patterns of dexmedetomidine over time. ⋯ Use of dexmedetomidine in critically ill patients has increased over time, primarily as a result of an increase in use among cardiac surgery patients. A substantial portion of dexmedetomidine was administered outside of the regulatory approval guidelines at the time.
-
Volume kinetics is a method used for analyzing and simulating the distribution and elimination of infusion fluids. Approximately 50 studies describe the disposition of 0.9% saline, acetated and lactated Ringer's solution, based on repeated measurements of the hemoglobin concentration and (sometimes) the urinary excretion. The slow distribution to the peripheral compartment results in a 50-75% larger plasma dilution during an infusion of crystalloid fluid than would be expected if distribution had been immediate. ⋯ Some of this temporary decrease can be attributed to the anesthesia and probably also to preoperative psychologic stress or dehydration. Crystalloid fluid might be allocated to "nonfunctional" fluid spaces in which it is unavailable for excretion. This amounts to approximately 20-25% during minor (thyroid) surgery.
-
Comparative Study
Feasibility and efficacy of preoperative epidural catheter placement for anterior scoliosis surgery.
Postoperative pain control via thoracic epidural catheters (TECs) is an important aspect of postoperative care, and ample evidence highlights its positive physiologic effects and superiority to intravenous analgesia. If epidural catheters for postoperative pain relief are used in scoliosis surgery, current practice is the intraoperative placement of the TEC by the surgeon because preoperative placement is considered challenging and dangerous. On the basis of magnetic resonance imaging of scoliotic spines, the authors developed a technique for preoperative placement of TEC and investigated its safety and feasibility. ⋯ The authors have demonstrated that it is possible to insert a TEC in patients with scoliotic spines with a high degree of success using a redesigned approach and thus provide adequate postoperative analgesia with a single epidural catheter. However, precautions have to be taken.