Comparison of average weekly pain using recalled paper and momentary assessment electronic diary reports in children with arthritis.

OBJECTIVE: The current study investigated the construct validity of a multidimensional pain diary for youth with juvenile idiopathic arthritis and also compared participants' responses on electronic and retrospective diary measures. The purpose of the latter part of this study was to compare absolute agreement, between-person and within-person consistency and judged change in weekly pain between these 2 methods of assessing pain. METHODS: A total of 70 adolescents with juvenile idiopathic arthritis completed both weekly recalled and momentary reports of pain over a 2-week period and assessed their change in pain over the 2-week period using a 5-point global change in pain scale. The Pearson correlations and intraclass correlation coefficients were computed to demonstrate 3 different ways of comparing the measures on both between-person and within-person basis. RESULTS: Momentary ratings of pain episodes were consistently greater than weekly ratings of recalled pain. Moderate to strong consistency and agreement correlations were computed for between-person momentary and recalled pain intensity. However, these correlations were much weaker when the within-person data were analyzed. The judged change in pain across weeks was significantly associated with computed change in both average momentary and recalled pain. DISCUSSION: This is one of the few studies to explore the relationship between the measurement methods of pain recall and momentary assessment in adolescents. The poor within-person correlations observed have important implications for research design and practice in pediatric pain.

Using an electronic pain diary to better understand pain in children and adolescents with arthritis.

UNLABELLED: Summary  AIM: To explore the pain experience of youths (9-18 years old) with juvenile idiopathic arthritis, using a real-time data capture electronic pain diary. MATERIALS & METHODS: A descriptive study design with repeated measures was used. A total of 76 youths, aged 9-18 years old with juvenile idiopathic arthritis were recruited from a Canadian pediatric tertiary care center and asked to record their pain three times a day for 2 weeks using the e-Ouch(©) pain diary. RESULTS: On average, participants reported mild levels of pain intensity, unpleasantness and interference, as well as stiffness and mild-to-moderate levels of fatigue. Interference of stiffness and pain with activities of daily living were significantly higher in the morning versus the afternoon and evening; while fatigue was significantly higher in the morning and evening compared with the afternoon. CONCLUSION: Real-time data capture approaches can be used enable a better understanding of how pain and other symptoms in youths with juvenile idiopathic arthritis change within and across days, and how best to treat them. Valuable next steps include incorporating the e-Ouch pain diary into an everyday clinical setting to measure patient outcomes.

Preparation of the Dräger Fabius GS workstation for malignant hyperthermia-susceptible patients.

PURPOSE: In order to establish guidelines for the preparation of the Dräger Fabius GS premium anesthetic workstation for malignant hyperthermia-susceptible patients, the authors evaluated the effect of the workstation's exchangeable and autoclavable components on the washout of isoflurane. METHODS: A Dräger Fabius GS workstation was primed with 1.5% isoflurane, and exchangeable components were replaced as follows: Group 1: no replacement (control); Group 2: autoclaved ventilator diaphragm and ventilator hose; Group 3: flushed ventilator diaphragm and ventilator hose; Group 4: autoclaved compact breathing system. The fresh gas flow (FGF) was set at 10 L . min(-1), and the concentration of isoflurane in the inspiratory limb of the circle breathing circuit was recorded every minute until an endpoint of 5.0 parts per million (ppm) was achieved, at which time the FGF was reduced to 3 L . min(-1). Six experiments were conducted in each of the four groups. RESULTS: The time to achieve an isoflurane concentration of 5.0 ppm decreased in the following order: Group 1 (151 +/- 17 min) > Group 3 (137 +/- 7 min) > Group 4 (122 +/- 11 min) > Group 2 (42 +/- 6 min) (P < 0.01 vs control). Isoflurane concentration increased approximately fivefold when the FGF was reduced to 3 L . min(-1). CONCLUSION: Anesthetic washout from the Dräger Fabius GS is relatively slow. Although washout was accelerated when the Dräger Fabius GS was equipped with autoclaved components, the reduction in washout time may be less than that required for this technique to be accepted into clinical practice. A dedicated vapor-free workstation may be preferable for rapid turnover between cases.

Construct validity of a multidimensional electronic pain diary for adolescents with arthritis.

The aim of this study was to evaluate the construct validity and feasibility of a multidimensional electronic pain diary (e-Ouch(c)) in adolescents with juvenile idiopathic arthritis (JIA). Two descriptive studies with repeated measures were conducted between January and December 2005. Participants were drawn from a large metropolitan rheumatology clinic in a university affiliated pediatric tertiary care centre. In Study 1, 76 adolescents with active arthritis recorded their pain three times a day for 2weeks using the e-Ouch(c). In Study 2, 36 adolescents recorded their pain three times a day for 1week before and 2weeks after joint injections. Adolescents in both studies completed multiple measures to determine the construct validity and feasibility of the e-Ouch(c). Adolescents reported mild levels of pain intensity, unpleasantness, and interference as well as stiffness, and mild to moderate levels of fatigue. e-Ouch(c) average weekly pain unpleasantness and interference scores were higher in adolescents with higher pain intensity scores. Correlations between average weekly pain ratings on the e-Ouch(c) and scores from: (a) recalled least, average and worst weekly pain, (b) health-related quality of life and pain coping, and (c) disease activity were as predicted. Pain ratings were significantly lower following joint injections with effect sizes in the low to moderate and moderate to high ranges at the first and second week post-injection, respectively. These findings provide evidence of the construct validity and feasibility of the e-Ouch(c) electronic diary in adolescents with JIA. Use of real-time data capture approaches should be considered in future studies of chronic arthritis.

Awareness during pediatric anesthesia: what is the position of European pediatric anesthesiologists?

BACKGROUND: The incidence of awareness in the pediatric population is reported as high as 1 : 125. An online survey was conducted about the current perception and practice of members of the British and French pediatric anesthesia societies regarding awareness during general anesthesia. METHODS: Following the approval of the executive committees of the British and French pediatric anesthesia societies, members with a valid email contact address were invited to participate in a web-based survey. Perceived risk factors, use of awareness monitors, pre- and postoperative discussions of awareness as well as personal experience were enquired. RESULTS: A total of 302 (51%) responded to the email survey. More than 60% indicated that awareness is a problem in pediatric anesthesia with the majority estimating an incidence of 1 : 1000. Almost half (49%) the respondents believe that awareness is age-dependent and 50% are not concerned below 1 month of age. More than 86% of respondents do not discuss the risk of awareness with the parents or actively look for awareness despite 27% reporting at least one episode in their practice. Intra-operative monitoring almost exclusively consists of clinical signs and endtidal anesthetic concentrations. Bispectral index (BIS) monitoring is routinely used by approximately 10% of the surveyed members. CONCLUSIONS: This survey demonstrates that European pediatric anesthesiologists perceive awareness as a major problem. However, none seems to address the issue openly or looks for its presence routinely. The vast majority of pediatric anesthesiologists rely almost exclusively on clinical monitoring and endtidal anesthetic concentrations for its detection.

Accelerating the washout of inhalational anesthetics from the Dräger Primus anesthetic workstation: effect of exchangeable internal components.

BACKGROUND: To establish guidelines for the preparation of the Primus anesthetic workstation (Dräger, Lübeck, Germany) for malignant hyperthermia-susceptible patients, the authors evaluated the effect of replacing the workstation's exchangeable internal components on the washout of isoflurane. METHODS: Primus workstations were exposed to isoflurane, and contaminated internal components were replaced as follows: group 1, no replacement; group 2, new ventilator diaphragm; group 3, autoclaved ventilator diaphragm; group 4, autoclaved integrated breathing system; group 5, flushed integrated breathing system; group 6, autoclaved ventilator diaphragm and integrated breathing system. The fresh gas flow was set at 10 l/min, and subsequently reduced to 3 l/min when a concentration of 5 ppm was achieved. Isoflurane concentration was measured in the inspiratory limb of the circle circuit every minute. RESULTS: Washout times for isoflurane decreased in the following order: group 1 (67 +/- 6.5 min) > groups 2 and 3 (50 +/- 4.1 and 50 +/- 5.7 min, respectively) > group 5 (43 +/- 9.5 min) > group 4 (12 +/- 1.5 min) > group 6 (3.2 +/- 0.4 min). Isoflurane concentration increased approximately threefold when the fresh gas flow was reduced to 3 l/min. CONCLUSION: Washout of isoflurane increased 20-fold with the use of an autoclaved ventilator diaphragm and integrated breathing system. To prepare the Primus for malignant hyperthermia-susceptible patients, the authors recommend replacing the ventilator diaphragm and integrated breathing system with autoclaved components, flushing the workstation for 5 min at a fresh gas flow of 10 l/min, and maintaining this flow for the duration of anesthesia.

A phase I, two-center study of the pharmacokinetics and pharmacodynamics of dexmedetomidine in children.

BACKGROUND: To investigate dexmedetomidine in children, the authors performed an open-label study of the pharmacokinetics and pharmacodynamics of dexmedetomidine. METHODS: Thirty-six children were assigned to three groups; 24 received dexmedetomidine and 12 received no drug. Three doses of dexmedetomidine, 2, 4, and 6 microg x kg x h, were infused for 10 min. Cardiorespiratory responses and sedation were recorded for 24 h. Plasma concentrations of dexmedetomidine were collected for 24 h and analyzed. Pharmacokinetic variables were determined using nonlinear mixed effects modeling (NONMEM program). Cardiorespiratory responses were analyzed. RESULTS: Thirty-six children completed the study. There was an apparent difference in the pharmacokinetics between Canadian and South African children. The derived volumes and clearances in the Canadian children were V1 = 0.81 l/kg, V2 = 1.0 l/kg, Cl1 (systemic clearance) = 0.013 l x kg x min, Cl2 = 0.030 l x kg x min. The intersubject variabilities for V1, V2, and Cl1 were 45%, 38%, and 22%, respectively. Plasma concentrations in South African children were 29% less than in Canadian children. The volumes and clearances in the South African children were 29% larger. The terminal half-life was 110 min (1.8 h). Median absolute prediction error for the two-compartment mammillary model was 18%. Heart rate and systolic blood pressure decreased with time and with increasing doses of dexmedetomidine. Respiratory rate and oxygen saturation (in air) were maintained. Sedation was transient. CONCLUSION: The pharmacokinetics of dexmedetomidine in children are predictable with a terminal half-life of 1.8 h. Hemodynamic responses decreased with increasing doses of dexmedetomidine. Respiratory responses were maintained, whereas sedation was transient.

Preparation of the Dräger Primus anesthetic machine for malignant hyperthermia-susceptible patients.

PURPOSE: Preparation of anesthesia machines for patients who are susceptible to malignant hyperthermia includes flushing the machine with vapour-free fresh gas to washout residual anesthetic agents. To establish guidelines for the preparation of the Dräger Primus machine, we compared the washout profiles for isoflurane and sevoflurane in the Dräger Primus and Ohmeda Excel 210 anesthesia machines. TECHNICAL FEATURES: The machines were primed with 1.5% isoflurane or 2.5% sevoflurane. Fresh gas flow (FGF) was set at 10 L.min(-1) during the early washout phase, and subsequently reduced to 3 L.min(-1) during the late washout phase. A Miran ambient air analyzer measured the anesthetic concentration every minute during washout until a concentration of 5 ppm was achieved in the inspiratory limb of the circle circuit. We found that at a FGF of 10 L.min(-1), maximum washout times for isoflurane and sevoflurane in the Primus, 70 and 74 min, respectively, were approximately tenfold greater than for isoflurane in the Excel 210 (7.0 min). Increasing the FGF to 18 L.min(-1) decreased the washout time for isoflurane in the Primus, only moderately, to 52 min. We observed a threefold increase in anesthetic concentration in the Primus during the late washout phase. CONCLUSION: We conclude that the Primus must be flushed for at least 70 min to decrease the anesthetic concentration to 5 ppm when using a FGF of 10 L.min(-1). We recommend maintaining a FGF of 10 L.min(-1) for the duration of anesthesia in order to prevent the rebound increase in anesthetic concentration in the FGF.

e-Ouch: usability testing of an electronic chronic pain diary for adolescents with arthritis.

OBJECTIVES: The aim of this study was to evaluate the usability of the e-Ouch electronic chronic pain diary in adolescents with juvenile idiopathic arthritis. METHODS: A qualitative usability testing approach with semistructured, audiotaped interviews with two iterative cycles was used. A purposive sample of 10 adolescents per cycle was drawn from a rheumatology clinic in a university-affiliated pediatric tertiary care center. Participants were provided with a brief demonstration of the diary and then asked to use the diary "thinking aloud" to record the pain they experienced: (1) when they woke up that morning, (2) during that afternoon, and (3) from the previous evening. Adolescents were then asked a series of open-ended questions addressing ease of use of the diary. Qualitative thematic analysis was used to generate categories and emerging themes from interview data. RESULTS: All of the adolescents stated the e-Ouch diary was very easy to learn, use, and understand and was satisfying to complete. Participants took less than 9 minutes to complete all three of the diary entries with minimal errors. The usability evaluation revealed aspects of the interface that were suboptimal (eg, VAS slider) and impeded the performance of certain tasks. Adolescents generated ideas on how the diary interface could be improved. CONCLUSIONS: A multifaceted usability approach provided important insight regarding the use of technology by adolescents with arthritis and, more specifically, for understanding how adolescents can more effectively use an electronic chronic pain diary.

Loss of resistance to normal saline is preferred to identify the epidural space: a survey of Canadian pediatric anesthesiologists.

PURPOSE: Several methods have been described to locate the epidural space, but the loss-of-resistance (LOR) technique is the most commonly used. Expert opinion states that LOR to air is the best medium for neonates and infants. We conducted a Canada-wide postal survey to determine the current state of practice for placement of epidural catheters in pediatric patients. METHODS: Two hundred and nine surveys were distributed to academic pediatric anesthesiologists across Canada. The survey was limited to six questions and was anonymous. RESULTS: The response rate was 62.2%. LOR was the method of choice for 124/130 anesthesiologists (95.4%). LOR to normal saline was the medium of choice for all age groups, although LOR to air and LOR to air/saline gained in popularity with increasing patient age. The majority of anesthesiologists do not change their LOR technique for different patient ages or level of epidural insertion. Most responders ranked 'training' as the most important determinant of practice, whereas 'departmental guidelines' were considered the least important. No complication attributable to the LOR technique used was reported. CONCLUSION: LOR to normal saline is the preferred method for identification of the epidural space in children of all age groups. The suggestion by experts that LOR to air should be used in neonates and infants was not supported by the practice of pediatric anesthesiologists across Canada.

Preparation of the Siemens KION anesthetic machine for patients susceptible to malignant hyperthermia.

BACKGROUND: Preparation of anesthetic machines for use with malignant hyperthermia-susceptible (MHS) patients requires that the machines be flushed with clean fresh gas. We investigated the washout of inhalational anesthetics from the KION anesthetic machine. METHODS: In part 1, halothane was circulated through KION anesthetic machines for either 2 or 12 h using a test lung. The times to washout halothane (to 10 parts per million [ppm]) first, from the internal circuitry and second, from the ventilator-patient cassette (without the carbon dioxide absorber) were determined at 5 and 10 l/min fresh gas flow (FGF). In part 2, the rates of washout of halothane or isoflurane from either the KION or Ohmeda Excel 210 machines were compared. The effluent gases were analyzed using calibrated Datex Capnomac Ultima (Helsinki, Finland) and a Miran LB2 Portable Ambient Air Analyzer (Foxboro, Norwalk, CT). RESULTS: Halothane was washed out of the internal circuitry of the KION within 5 min at 10 l/min FGF. Halothane was eliminated from the ventilator-patient cassette in 22 min at the same FGF. The times to reach 10 ppm concentration of halothane and isoflurane in the KION at 10 l/min FGF, 23 to 25 min, was four-fold greater than those in the Ohmeda Excel 210, 6 min. CONCLUSIONS: To prepare the KION anesthetic machine for MHS patients, the machine without the carbon dioxide absorber must be flushed with 10 l/min FGF for at least 25 min to achieve 10 ppm anesthetic concentration. This FGF should be maintained throughout the anesthetic to avoid increases in anesthetic concentration in the FGF.