Anesthesia and analgesia
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Anesthesia and analgesia · Dec 1996
Randomized Controlled Trial Comparative Study Clinical TrialComparison of a modified double-lumen endotracheal tube with a single-lumen tube with enclosed bronchial blocker.
This study compared the modified BronchoCath double-lumen endotracheal tube with the Univent bronchial blocker to determine whether there were objective advantages of one over the other during anesthesia with one-lung ventilation (OLV). Forty patients having either thoracic or esophageal procedures were randomly assigned to one of two groups. Twenty patients received a left-side modified BronchoCath double-lumen tube (DLT), and 20 received a Univent tube with a bronchial blocker. ⋯ Blinded evaluations by surgeons indicated that 18/20 DLT provided excellent exposure compared to 15/20 for the Univent group (P = not significant). We conclude that in spite of the greater frequency of malposition seen with the Univent, once position was corrected adequate surgical exposure was provided. In the Univent group the incidence of malposition and cost involved were both sufficiently greater that we cannot find cost/ efficacy justification for routine use of this device.
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Anesthesia and analgesia · Dec 1996
Randomized Controlled Trial Clinical TrialThe safety and efficacy of oral transmucosal fentanyl citrate for preoperative sedation in young children.
Oral transmucosal fentanyl citrate (OTFC) is a labeled preoperative pediatric sedative. Doses greater than 15 micrograms/kg are associated with a high incidence of post-operative nausea and vomiting and occasional respiratory depression. We studied the safety and efficacy of OTFC in children 6 yr old and younger at a dose of 15 micrograms/kg. ⋯ One OTFC patient developed rigidity during induction. Emergence and recovery were not delayed by OTFC despite a 50% incidence of postoperative vomiting. We do not recommend the use of OTFC in a 15 micrograms/kg dose as a routine preoperative sedative in children 6 yr old and younger.
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Anesthesia and analgesia · Dec 1996
Biphasic drug absorption from the epidural space of the dog may limit the utility of a slow release medium molecular weight hyaluronic acid-lidocaine ionic complex formulation.
Previous epidural studies conducted in rabbits have described a viscous lidocaine-hyaluronate formulation (L-HA) that prolonged the duration of sensory blockade twofold and decreased the rate of drug absorption fourfold relative to a solution formulation. As further evaluation of the L-HA formulation required studies in a larger animal that more closely reflected the characteristic absorption kinetics observed in humans, a conscious dog model was used to functionally and kinetically evaluate the viscous formulation relative to lidocaine solution. In terms of the measured pharmacodynamic end point (loss of weight-bearing ability in hind legs), epidural administration of the L-HA formulation did not prolong the duration of action relative to lidocaine solution in spite of a markedly altered pharmacokinetic profile. ⋯ The L-HA formulation markedly altered the absorption kinetics such that a single, slow absorption phase was evident (apparent t1/2 of 56 min), although this rate was more rapid than the slow phase observed after lidocaine solution. It is possible that the inability of the hyaluronate-based formulation to further reduce the magnitude of the slow absorption phase resulted in the failure to prolong the duration of action. These data highlight the need to carefully consider the absorption kinetics and pharmacokinetic characteristics of the animal models chosen to evaluate new formulation of epidurally administered local anesthetics.
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Anesthesia and analgesia · Dec 1996
Comparative StudyDelayed time response of the continuous cardiac output pulmonary artery catheter.
Previous studies of the accuracy of pulmonary artery catheters (PAC) which provide continuous cardiac output (CCO) monitoring have investigated the performance during steady-state conditions. We compared the response time to hemodynamic change using a CCO PAC and an ultrasonic flow probe (UFP). In five sheep, a CCO PAC was inserted, and an UFP for measurement of CCO was placed around the pulmonary artery via a left thoracotomy. ⋯ The time interval for 80% change was 14.5 +/- 4.1 min for CCO versus 1.8 +/- 0.9 min with UFP. The current study demonstrates clinically important time delays in the response of the CCO catheter. This delay must be considered when rapid alterations of the hemodynamic state may occur.