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Melissa Wheeler

Publications and source records attributed to Melissa Wheeler.

13 recordsLinked to original sources
PubMed2006

ProSeal laryngeal mask airway in 120 pediatric surgical patients: a prospective evaluation of characteristics and performance.

BACKGROUND: The ProSeal LMA (PLMA) has recently been introduced in pediatric sizes (1.5, 2, 2.5, 3). Limited pediatric data have been published. METHODS: After Institutional Review Board (IRB) approval, the PLMA was placed in 120 children aged 4 months to 13 years (5-50 kg). The following data were collected prospectively: induction agent, number of placement attempts (limited to three), placement success or failure, PLMA size, leak pressure, ventilatory pattern [spontaneous (SV) or controlled positive pressure ventilation (PPV)], success or failure of gastric suction tube placement, hypoxemia, dislodgement, laryngospasm, bronchospasm, aspiration, and traumatic placement. RESULTS: The PLMA was easily placed in children with a higher first attempt success rate (94%) than reported for adults. Overall PLMA and gastric tube placement were both 100% successful. Leak pressures were similar to those reported for the PLMA in adults and higher than reported for the Classic LMA in children. No bronchospasm, laryngospasm, hypoxemia, dislodgement, or aspiration occurred. CONCLUSIONS: Although the PLMA can be used with SV or PPV, the higher leak pressure achieved with the PLMA, and the ability to evacuate fluid and air from the stomach suggest that it may be a useful alternative to tracheal intubation for procedures in which PPV is desired in children aged 4 months to 13 years.

Adolescent↗
PubMed2005

The addition of clonidine 2 microg.kg-1 does not enhance the postoperative analgesia of a caudal block using 0.125% bupivacaine and epinephrine 1:200,000 in children: a prospective, double-blind, randomized study.

BACKGROUND: In this prospective, randomized, double-blind study, we compared the efficacy of 0.125% bupivacaine and epinephrine 1:200,000 with and without clonidine 2 microg.kg-1 for 'single shot' pediatric caudal analgesia. METHODS: Thirty ASA I and II children, ages 2-8 years, undergoing outpatient surgical procedures below the umbilicus received 1 ml.kg-1 0.125% bupivacaine with fresh epinephrine 1:200,000 and clonidine 2 microg.kg-1 (group-C) or 1 ml.kg-1 0.125 % bupivacaine with epinephrine 1:200 000 (group-NC). All patients received a standardized general anesthetic (induction with 67% N2O in O2 and sevoflurane followed by isoflurane maintenance). Primary outcome measures were time to first rescue analgesic and number of patients requiring rescue analgesic at 4, 6, 8, 12, and 24 h after caudal placement. Secondary outcome measures included: extubation times, Objective Pain Scale (OPS) scores, sedation scores, time in postanesthesia care unit (PACU), discharge time, number of analgesic doses given in 24 h following caudal blockade, and adverse effects (vomiting, hypotension, and bradycardia). RESULTS: There were no differences in demographics, investigated parameters, or adverse effects between groups. CONCLUSIONS: We found that the addition of clonidine 2 microg.kg-1 to 0.125% bupivacaine with fresh epinephrine 1:200,000 for caudal analgesia did not significantly delay the time to first rescue analgesic or decrease the overall need for rescue analgesics in children 2-8 years undergoing surgical procedures below the umbilicus.

Adjuvants, Anesthesia↗
PubMed2004

Teaching residents pediatric fiberoptic intubation of the trachea: traditional fiberscope with an eyepiece versus a video-assisted technique using a fiberscope with an integrated camera.

BACKGROUND: The authors' hypothesis was that a video-assisted technique should speed resident skill acquisition for flexible fiberoptic oral tracheal intubation (FI) of pediatric patients because the attending anesthesiologist can provide targeted instruction when sharing the view of the airway as the resident attempts intubation. METHODS: Twenty Clinical Anesthesia year 2 residents, novices in pediatric FI, were randomly assigned to either the traditional group (traditional eyepiece FI) or the video group (video-assisted FI). One of two attending anesthesiologists supervised each resident during FI of 15 healthy children, aged 1-6 yr. The time from mask removal to confirmation of endotracheal tube placement by end-tidal carbon dioxide detection was recorded. Intubation attempts were limited to 3 min; up to three attempts were allowed. The primary outcome measure, time to success or failure, was compared between groups. Failure rate and number of attempts were also compared between groups. RESULTS: Three hundred patient intubations were attempted; eight failed. On average, the residents in the video group were faster, were three times more likely to successfully intubate at any given time during an attempt, and required fewer attempts per patient compared to those in the traditional group. CONCLUSIONS: The video system seems to be superior for teaching residents fiberoptic intubation in children.

Child↗
PubMed2004

The pharmacokinetics of the intravenous formulation of fentanyl citrate administered orally in children undergoing general anesthesia.

The bioavailability of oral transmucosal fentanyl citrate (OTFC) in children is similar to that of fentanyl solution administered orally to adults. We hypothesized that administering an oral fentanyl solution to children would result in similar fentanyl plasma concentrations and pharmacokinetic variables as administering comparable doses of OTFC. In this pilot study, 10 healthy children requiring postoperative analgesia were enrolled. Each received the undiluted IV fentanyl formulation orally (approximately 10-15 microg/kg; maximum, 400 microg). Venous blood samples were collected from 15 to 600 min after administration. Pharmacokinetic variables were determined using noncompartmental analysis and were compared with a previously studied population of children who received a similar dose of OTFC. Pharmacokinetic variables for the orally administered IV fentanyl formulation were as follows: time to reach peak concentration = 1.7 +/- 1.6 h, peak concentration = 1.83 +/- 1.19 ng/mL, half-life = 4.7 +/- 2.8 h, area under the plasma concentration time curve = 6.46 +/- 3.96 h . ng(-1) . mL(-1), apparent oral volume of distribution (V/F) = 17.5 +/- 7.2 L/kg, apparent oral clearance (CL/F) = 3.33 +/- 2.25 L . kg(-1) . h(-1). Although both OTFC and orally administered IV fentanyl resulted in similar pharmacokinetic variables and plasma concentrations for a given dose, there was marked interpatient variability, particularly in the early hours after oral administration of the IV formulation of fentanyl. This suggests that this method of administration be used with caution until further data are available.

Administration, Oral↗
PubMed2003

Traditional versus new needle retractable i.v. catheters in children: are they really safer, and whom are they protecting?

Retractable needle IV catheters are designed to reduce needle-stick injuries; their use is mandated by federal regulations. We undertook a prospective data collection with the "traditional" IV catheters (JELCO) versus the "new" (Angiocath Autoguard). Assignment of catheter type was randomized by week. Data collected included assessment of the difficulty of i.v. access; number of catheters used; and splatters or spills of blood on skin, linen, floor, clothing, and operating room table. There were 473 attempted insertions in 330 patients over 20 days. No needle-stick injuries occurred. Seventy-seven blood spills or splatters occurred in 42 patients. The number of splatters or spills was four times more with the new compared with the traditional catheters. There were significantly more total splatters or spills and patients who experienced splatters or spills with new catheters when they were placed by attendings but not when placed by trainees. Our study suggests that use of this technology by more experienced anesthesiologists may increase the risk of exposure of health care providers to blood-borne pathogens. Practitioners should choose the i.v. system that allows the most efficient venous access with the least potential for blood contamination. Hospitals should allow the choice to be made by the individuals using the devices.

Catheterization, Peripheral↗
PubMed2003

Patient-controlled epidural analgesia in children: can they do it?

UNLABELLED: Extensive clinical experience and many studies support the use of i.v. patient-controlled analgesia (i.v. PCA) and regional anesthesia techniques for the treatment of postoperative pain in children. In contrast, little has been reported about the ability of children to use patient-controlled epidural analgesia (PCEA) or about the efficacy of this technique. We report a descriptive analysis of prospectively recorded data in 128 children (132 procedures) in whom PCEA was used for acute postoperative pain control. Satisfactory analgesia was obtained in 119 patients (90.1%) for up to 103 h with no episodes of desaturation and without clinical evidence of toxicity or serious adverse effects. Analgesia was satisfactory with the initial settings in 89 patients; in 38 others, this was achieved with changes in PCEA settings or solution. Five patients were switched to i.v. PCA because of inadequate analgesia. Eight patients with satisfactory analgesia were converted to i.v. PCA because of adverse effects. Children as young as 5 yr had the cognitive ability to understand and the willingness to use PCEA, consistent with reported use of i.v. PCA. Careful attention should be paid to the total hourly local anesthetic dose to avoid exceeding the recommended limits. Our prospectively collected data demonstrate that PCEA provides satisfactory analgesia with a small incidence of adverse side effects in children and should be considered along with other strategies in pediatric postoperative pain management. IMPLICATIONS: A descriptive analysis of prospectively recorded data in 132 children receiving patient-controlled epidural analgesia for postoperative pain relief demonstrates satisfactory analgesia without serious toxicity or side effects in children as young as 5 yr. This modality should be considered as another strategy in pediatric postoperative pain management.

Adolescent↗
PubMed2002

Practical pediatric regional anesthesia.

In children, regional anesthetic techniques are safe and effective adjuncts to general anesthesia and for postoperative pain relief. Application of the techniques described in this article will contribute to improved care for pediatric patients undergoing surgical procedures. The judicious choice of local anesthetics, along with the blockades of targeted nerves, decrease the need for supplemental analgesics in the recovery phase.

Abdomen↗
PubMed2002

Uptake pharmacokinetics of the Fentanyl Oralet in children scheduled for central venous access removal: implications for the timing of initiating painful procedures.

BACKGROUND: The Fentanyl Oralet (Abbott Laboratories, Abbott Park, IL, USA) is an oral transmucosal drug delivery system. We previously examined pharmacokinetic parameters of children who had completed consumption of the Fentanyl Oralet. The present study was designed to clarify pharmacokinetic parameters during the consumption phase to determine if there is an optimal administration time before painful procedures. METHODS: Patients, aged 3-10 years, who were scheduled for elective removal of central venous access devices under general anaesthesia, received a Fentanyl Oralet (fentanyl 10-15 microg x kg(-1)). Plasma fentanyl concentrations were measured by radioimmunoassay. Data from blood samples obtained during and after consumption of the Fentanyl Oralet from 17 patients in the present study were combined with data from our previous study to better characterize both the consumption and postconsumption concentration versus time profiles. RESULTS: Estimated fentanyl bioavailability (mean +/- SD) was low (36.1 +/- 0.4%), as were peak plasma concentrations (1.03 +/- 0.31 ng.ml-1), suggesting that many children swallowed a large fraction of the dose. This led to a relatively late and variable peak concentration time of 53 +/- 40 min. In addition, because of the apparently large degree of gastrointestinal absorption, concentration versus time curves were wide and flat. CONCLUSIONS: The wide and flat concentration versus time profile may allow flexibility in the timing of a painful procedure following Fentanyl Oralet administration. However, the variability of the time to peak concentration makes it difficult to suggest a minimum interval between Fentanyl Oralet consumption and the start of a painful procedure.

Administration, Buccal↗
PubMed2002

Age-stratified pharmacokinetics of ketorolac tromethamine in pediatric surgical patients.

UNLABELLED: 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. IMPLICATIONS: 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.

Adolescent↗