Anesthesia and analgesia
-
Anesthesia and analgesia · Feb 2002
Randomized Controlled Trial Comparative Study Clinical TrialRopivacaine undergoes slower systemic absorption from the caudal epidural space in children than bupivacaine.
We compared the systemic absorption of ropivacaine and bupivacaine after caudal epidural administration in children. Twenty ASA physical status I or II children aged 1-7 yr undergoing elective hypospadias repair were randomized after the induction of general anesthesia to receive a single caudal epidural injection of 2 mg/kg of either ropivacaine 0.2% (R) or bupivacaine 0.2% (B) in a double-blinded fashion. Peripheral venous blood samples (1 mL) were obtained before and 1, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, and 120 min after the caudal injection. The total R and B concentration was measured in plasma by using high-performance liquid chromatography. All blocks were successful, and there were no complications. The peak plasma concentration (mean +/- SD) (R = 0.67 +/- 0.16 and B = 0.73 +/- 0.23 microg/mL) and the area under the plasma concentration curve (R = 61.9 +/- 20.6 and B = 62.7 +/- 18.2 microg x mL(-1) x min(-1)) were comparable between the two study groups. The median (range) time to attain peak plasma concentration was significantly slower in children who received ropivacaine (R = 65 [10-120] min and B = 20 [15-50] min, P < 0.05). We conclude that ropivacaine undergoes slower systemic absorption from the caudal epidural space in children than does bupivacaine. ⋯ We compared the systemic absorption of ropivacaine (0.2%) and bupivacaine (0.2%) after caudal epidural injection of 2 mg/kg in children aged 1-7 yr. Our results show that ropivacaine undergoes slower systemic absorption from the caudal epidural space in children than does bupivacaine.
-
Anesthesia and analgesia · Feb 2002
Age-stratified pharmacokinetics of ketorolac tromethamine in pediatric surgical patients.
Published data suggest that ketorolac pharmacokinetics are different in children than in adults. We sought to better characterize ketorolac pharmacokinetics in children. Thirty-six children, aged 1-16 yr, were stratified into four age groups: 1-3 yr, 4-7 yr, 8-11 yr, and 12-16 yr. Each child received 0.5 mg/kg of ketorolac tromethamine IV after completion of elective surgery. A maximum of 16 venous blood samples (mean, 13 +/- 2) were collected at predetermined times up to 10 h after drug administration. Plasma ketorolac concentrations were measured by high-performance liquid chromatography after solid-phase extraction. Individual concentration-versus-time relationships were best fit to a two-compartment pharmacokinetic model by using SAAM II. Body weight-normalized pharmacokinetic variables did not differ among the age groups and were similar to those reported for adults, including a volume of distribution at steady state of 113 +/- 33 mL/kg (mean +/- SD) and an elimination clearance of 0.57 +/- 0.17 mL x min(-1) x kg(-1). Our study demonstrates that a single dose of ketorolac (0.5 mg/kg) results in plasma concentrations in the adult therapeutic concentration range for 6 h in most children. Our data provide no evidence that children require either larger weight-adjusted doses or shorter dosing intervals than adults to provide similar plasma drug concentrations. ⋯ The literature suggests that ketorolac disposition differs between children and adults. We characterized ketorolac pharmacokinetics in 36 children. Body weight-normalized two-compartment pharmacokinetic variables did not differ among pediatric patients <17 yr old and were similar to adult values.
-
Anesthesia and analgesia · Feb 2002
Case ReportsDifficult retrograde endotracheal intubation: the utility of a pharyngeal loop.
Direct laryngoscopy and tracheal intubation remains the technique of choice to achieve control of the airway. Alternative or additional techniques of airway control are required whenever an airway is deemed difficult because of anatomical and/or technical reasons. The retrograde intubation technique is an important option for gaining airway access from below the vocal cords in such situations (1). We report successful management and the problems encountered while gaining the upper airway by the retrograde catheter method in a patient having bilateral fibrous ankylosis of the temporomandibular joint (TMJ). ⋯ A 30-yr-old woman presented for redo-release of bilateral temporomandibular joint ankylosis under general anesthesia. During the previous anesthetic for primary release of ankylosis, tracheostomy was done, as conventional blind nasotracheal and retrograde intubation attempts failed several times. This case report describes the method for overcoming the difficulties of a retrograde intubation procedure in removing the guiding catheter nasally by using a pharyngeal loop assembly.