Search

Background In pediatric patients, the Bispectral Index (BIS), derived from the electroencephalogram, and the composite A-Line autoregressive index (cAAI), derived from auditory evoked potentials and the electroencephalogram, have been used as measurements of depth of hypnosis during anesthesia. The performance and reliability of BIS and cAAI in distinguishing different hypnotic states in children, as evaluated with the University of Michigan Sedation Scale, were compared. Methods Thirty-nine children (aged 2-16 yr) scheduled to undergo elective inguinal hernia surgery were studied. For all patients, standardized anesthesia was used. Prediction probabilities of BIS and cAAI versus the University of Michigan Sedation Scale and sensitivity/specificity were calculated. Results Prediction probabilities for BIS and cAAI during induction were 0.84 for both and during emergence were 0.75 and 0.74, respectively. At loss of consciousness, the median BIS remained unaltered (94 to 90; not significant), whereas cAAI values decreased (60 to 43; P < 0.001). During emergence, median BIS and cAAI increased from 51 to 74 (P < 0.003) and from 46 to 58 (P < 0.001), respectively. With respect to indicate consciousness or unconsciousness, 100% sensitivity was reached at cutoff values of 17 for BIS and 12 for cAAI. One hundred percent specificity was associated with a BIS of 71 and a cAAI of 60. To ascertain consciousness, BIS values greater than 78 and cAAI values above 52 were required. Conclusions BIS and cAAI were comparable indicators of depth of hypnosis in children. Both indices, however, showed considerable overlap for different clinical conditions.

Background The safety and value of acetaminophen (paracetamol) in addition to continuous morphine infusion has never been studied in newborns and young infants. We investigated the addition of acetaminophen to evaluate whether it decreased morphine consumption in this age group after major thoracic (non-cardiac) or abdominal surgery. Methods A randomized controlled trial was performed in 71 patients given either acetaminophen 90–100 mg kg −1 day −1 or placebo rectally, in addition to a morphine loading dose of 100 µg kg −1 and 5–10 µg kg −1 h −1 continuous infusion. Analgesic efficacy was assessed using Visual Analogue Scale (VAS) and COMFORT scores. Extra morphine was administered if VAS was ≥4. Results We analysed data of 54 patients, of whom 29 received acetaminophen and 25 received placebo. Median (25–75th percentile) age was 0 (0–2) months. Additional morphine bolus requirements and increases in continuous morphine infusion were similar in both groups ( P = 0.366 and P = 0.06, respectively). There was no significant difference in total morphine consumption, respectively, 7.91 (6.59–14.02) and 7.19 (5.45–12.06) μg kg −1 h −1 for the acetaminophen and placebo group ( P = 0.60). COMFORT [median (25–75th percentile) acetaminophen 10 (9–12) and placebo 11 (9–13)] and VAS [median (25–75th percentile) acetaminophen 0.0 (0.0–0.2) and placebo 0.0 (0.0–0.3)] scores did not differ between acetaminophen and placebo group ( P = 0.06 and P = 0.73, respectively). Conclusions Acetaminophen, as an adjuvant to continuous morphine infusion, does not have an additional analgesic effect and should not be considered as standard of care in young infants, 0–2 months of age, after major thoracic (non-cardiac) or abdominal surgery.

Objectives: To evaluate over a 5-yr period the feasibility and tolerance of a protocol of routine enteral nutrition in neonates requiring extracorporeal membrane oxygenation (ECMO). Design: Retrospective medical chart review. Setting: Level III children’s hospital, pediatric surgical intensive care unit. Patients: Neonates treated with venoarterial ECMO (VA-ECMO) between January 1997 and January 2002. Patients with congenital diaphragmatic hernia were excluded. Interventions: None. Measurements and Main Results: Charts of all neonates treated with VA-ECMO were reviewed. Feasibility was evaluated by recording the time period needed for enteral nutrition to reach 40% of total fluid intake; tolerance was evaluated by reviewing data on enteral nutrition related morbidity. Sixty-seven of the 77 eligible patients received enteral feeding during ECMO. Thirty-six of these patients (54%) received 40% of total fluid intake as enteral nutrition within a median of 3 (range, 2–4) days. Over the years there was a trend toward an increasing usage of enteral nutrition from 71% to 94% (p = .07). Enteral nutrition was temporarily discontinued in 16 patients, with 14 showing gastric retentions, one showing discomfort, and one showing aspiration. Symptoms of bilious vomiting, blood-stained stool, or abdominal distention were not present. Conclusion: Neonates on ECMO in this series tolerated enteral feeding well and did not show serious adverse effects. Overall, it is our experience that routine use of enteral feeding in critically ill neonates on VA-ECMO is feasible.

In children, patient controlled analgesia (PCA) and continuous infusion (CI) of morphine are well established methods of relieving postoperative pain. This study was designed to assess the efficacy of PCA plus background infusion (BI) (15 microg x kg(-1) x h(-1) and bolus doses of 15 microg x kg(-1) with a lock-out interval of 10 min) with CI (20 to 40 microg x kg(-1) x h(-1)) in terms of analgesia, morphine needs and side-effects. A stratified randomized controlled trial was carried out. 47 children aged 5-18 years undergoing major elective lower/upper abdominal or spinal surgery were allocated. The magnitude of surgery was assessed by the Severity of Surgical Stress scoring (SSS) system. Pain was assessed by self-report every three h. Side-effects compatible with morphine as well as morphine consumption were recorded. Morphine consumption was significantly increased in the PCA group compared with the CI group. Moreover, morphine consumption was associated with SSS, independent of the technique of administration. There were no significant differences between groups in pain scores or in the incidence of side-effects.

Concerns exist about the optimal analgesic for postoperative pain management following (adeno)tonsillectomy. Hence, we decided to review the efficacy of paracetamol (acetaminophen) and diclofenac in children aged 3 to 12 years after (adeno)tonsillectomy Pharmacokinetics and adverse effects of the two agents were also addressed. A MEDLINE search (1966 to 1998), review articles and textbooks were used as data sources. In general, systematic and practice-based research on these drugs for this indication is scarce. Paracetamol 20 mg/kg administered orally, 60 minutes preoperatively, and diclofenac 2 mg/kg administered rectally at induction seem to achieve satisfactory analgesia in the majority of children during the first few hours postoperatively.

The purpose of this clinical trial was to investigate the safety and efficacy of semi-closed circle ventilation of the Drager anaesthesia ventilators (Cicero, Cato), using a fresh gas flow (FGF) of 600ml.min -1 . Twenty infants, weighing less than 6000g, without cardiorespiratory abnormalities who required general anaesthesia of at least 30 min were included. The FGF was reduced to 600ml.min -1 after 10 min of denitrogenation with a FGF of 4 to 6 l.min -1 . The composition of the FGF (600ml.min -1 ) was calculated as follows: oxygen necessary for consumption (60ml.min -1 ) plus the remaining FGF in a 1:2 relationship for oxygen. The inspiratory nitrogen fraction was calculated to exclude accumulation. Inspiratory fractions of 02 and N 2 O plus inspiratory and endtidal CO 2 partial pressures and noninvasive oxygen saturation were the control parameters. The gas concentrations (02 and N 2 O) remained within safe limits. Hypoxic gas concentrations were not observed. Neither nitrogen nor CO 2 accumulated in the circle system. In conclusion, low flow anaesthesia can be performed safely in infants under 6000 grams with the Drager Cicero and Cato anaesthesia ventilators.

BACKGROUND: The electroencephalogram-derived Bispectral Index (BIS), and the composite A-line ARX index (cAAI), derived from the electroencephalogram and auditory evoked potentials, have been promoted as anesthesia depth monitors. Using an intracoperative wake-up test, we compared the performance of both indices in distinguishing different hypnotic states, as evaluated by the University of Michigan Sedation Scale, in children and adolescents during propofol-remifentanil anesthesia for scoliosis surgery. Postoperative explicit recall was also evaluated. METHODS: Twenty patients (aged 10-20 yr) were enrolled. Prediction probabilities were calculated for induction, wake-up test, and emergence. BIS and cAAI were compared at the start of the wake-up test, at purposeful movement to command, and after the patient was reanesthetized. During the wake-up test, patients were instructed to remember a color, and were then interviewed for explicit recall. RESULTS: Prediction probabilities of BIS and cAAI for induction were 0.82 and 0.63 (P < 0.001), for the wake-up test, 0.78 and 0.79 (P < 0.001), and 0.74 and 0.78 for emergence (P < 0.001). During the wake-up test, a significant increase in mean BIS and cAAI (P < 0.05) was demonstrated at purposeful movement, followed by a significant decline after reintroduction of anesthesia. CONCLUSIONS: During induction, BIS performed better than cAAI. Although cAAI was statistically a better discriminator for the level of consciousness during the wake-up test and emergence, these differences do not appear to be clinically meaningful. Both indices increased during the wake-up test, indicating a higher level of consciousness. No explicit recall was demonstrated.

Objective: To examine morphine metabolite serum concentrations in neonates undergoing venoarterial extra corporeal membrane oxygenation (ECMO) and to quantify clearance differences between these neonates and those subjected to noncardiac major surgery. Patients and methods: This was an observational study in level III referral centre Fourteen neonates (

To study morphine pharmacokinetics in neonates undergoing venoarterial ECMO and to quantify differences between these neonates and neonates subjected to noncardiac major surgery.Observational study in a level III referral center.Pharmacokinetic estimates from 14 neonates undergoing ECMO were compared with findings from a previous study in 0- to 3-year-olds after noncardiac major surgery using a nonlinear mixed effect model. A one-compartment linear disposition model with zero-order input (infusion) and first-order elimination was used to describe all data.Clearance in neonates (age7 days) at the start of ECMO (2.2 l per hour per 70 kg) was lower than that in postoperative neonates (10.5 l per hour per 70 kg) but increased rapidly (maturation half-life 30 and 70 days, respectively) and equaled that of the postoperative group after 14 days. Clearance was affected by size and age only. Exchange transfusion, when used, contributed only 1.1% (CV 46%) of total clearance. Distribution volume increased with age and was 2.5 times (CV 102%) greater in ECMO children than in postoperative children. The between-subject variability values for volume of distribution and clearance were 49.4% and 38.7%. Weight and age information explained 83% of the overall clearance variability and 60% of overall distribution volume variability.Morphine clearance is reduced in infants requiring ECMO, possibly reflecting severity of illness. Clearance maturation on ECMO is rapid and normalizes within 2 weeks. Initial morphine dosing may be guided by age and weight, but clearance and distribution volume changes (and their variability) during prolonged ECMO suggests that morphine therapy should be subsequently guided by clinical monitoring.

Does pain or tissue damage in early life lead to hyperalgesia persisting into childhood? We performed a cross-sectional study in 164 infants to investigate whether major surgery within the first 3 months of life increases pain sensitivity to subsequent surgery and to elucidate whether subsequent surgery in the same dermatome or in a different dermatome leads to differences in pain sensitivity. All infants received standard intraoperative and postoperative pain management, with rescue analgesia guided by a treatment algorithm. Differences in pain sensitivity during surgery were assessed by the intraoperative fentanyl intake and by (nor)epinephrine plasma concentrations. Differences in postoperative pain sensitivity were assessed by the observational pain measures COMFORT and VAS, and by morphine intake and (nor)epinephrine plasma concentrations. Infants previously operated upon in the same dermatome needed more intraoperative fentanyl, had higher COMFORT and VAS scores, had greater (nor)epinephrine plasma concentrations, and needed also more morphine than did infants with no prior surgery. In contrast, infants who previously underwent surgery in another dermatome had only significant higher postoperative analgesic requirements and norepinephrine plasma concentrations in comparison with infants with no prior surgery. These preliminary differences may indicate the occurrence of spinal and supraspinal changes following neonatal surgery. We conclude that the long-term consequences of surgery in early infancy are greater in areas of prior tissue damage and that these effects may portend limited clinical but important neurobiological differences.