How do pediatric anesthesiologists define intraoperative hypotension?

Introduction: Although blood pressure (BP) monitoring is a recommended standard of care by the ASA, and pediatric anesthesiologists routinely monitor the BP of their patients and when appropriate treat deviations from ‘normal’, there is no robust definition of hypotension in any of the pediatric anesthesia texts or journals. Consequently, what constitutes hypotension in pediatric anesthesia is currently unknown. We designed a questionnaire‐based survey of pediatric anesthesiologists to determine the BP ranges and thresholds used to define intraoperative hypotension (IOH). Methods: Members of the Society of Pediatric Anesthesia (SPA) and the Association of Paediatric Anaesthetists (APA) of Great Britain and Ireland were contacted through e‐mail to participate in this survey. We asked a few demographic questions and five questions about specific definitions of hypotension for different age groups of patients undergoing inguinal herniorraphy, a common pediatric surgical procedure. Results: The overall response rate was 56% (483/860), of which 76% were SPA members. Majority of the respondents (72%) work in academic institutions, while 8.9% work in institutions with fewer than 1000 annual pediatric surgical caseload. About 76% of respondents indicated that a 20–30% reduction in baseline systolic blood pressure (SBP) indicates significant hypotension in children under anesthesia. Most responders (86.7%) indicated that they use mean arterial pressure or SBP (72%) to define IOH. The mean SBP values for hypotension quoted by SPA members was about 5–7% lower across all pediatric age groups compared to values quoted by APA members (P = 0.001 for all age groups). Conclusions: There is great variability in the BP parameters used and the threshold used for defining and treating IOH among pediatric anesthesiologists. The majority of respondents considered a 20–30% reduction from baseline in SBP as indicative of significant hypotension. Lack of a consensus definition for a common clinical condition like IOH could have implications for patient care as well as future clinical research.     

Solvent effects on the conformation of cyclo(-D-Trp-D-Asp-Pro-D-val-Leu-) An NMR spectroscopy and molecular modeling study

The conformations of cyclo(-D-Trp-D-Asp-Pro-D-val-Leu-) in dimethyl sulfoxide-d₆ (DMSO-d₆) and water were determined using two-dimensional nuclear magnetic resonance spectroscopy and restrained molecular dynamics. Comparisons were made between conformations of the cyclic pentapeptide in both solvents. The NMR study revealed that, while the backbone remained relatively unchanged in both solvents, the side-chains adopted distinctly different orientations in DMSO-d₆ vs. H₂O. A modeling study, minus NOE constraints, produced a set of low-energy conformers possessing agreement in backbone conformation with the NMR-derived structures; however, lowest-energy conformers did not have this agreement. These results show that different solvents can significantly affect the preferred side-chain conformation of small cyclic peptides in solution. This finding will impact the selection of solvent when determining structures for use as templates in rational drug design.     

Young People and AIDS Mental Health Promotion in Action

This article describes the development and implementation of a two part health promotion and primary mental health prevention program developed for junior high students. AIDS education was used as a vehicle for promoting the development of a responsible decision-making framework in the students. Both cognitive and affective learning strategies were used in the program. The reactions of the students, their parents, and the educational system are described.     

ortho-Toluidine Blood Protein Adducts: HPLC Analysis with Fluorescence Detection after a Single Dose in the Adult Male Rat

Hemoglobin (Hb) and albumin (Alb) adducts of the suspect humancarcinogen ortho-toluidine (OT) were quantified in blood samplescollected from rats after a single i.p. injection. Mild alkalinehydrolysis of Hb adducted with [¹⁴C]OT followed by extractionwith ethyl acetate resulted in recovery of 63% of the boundradioactivity. HPLC analysis revealed a single radiolabeledpeak which was identified as OT by GC-MS. In subsequent experimentsHb and Alb adduct levels were determined by HPLC analysis ofthis cleavage product using fluorescence detection. 4-Ethylanilinewas used as internal standard. The detection limit for OT wasapproximately 450 pg/injection or 5 pmol/mg Hb. Mean adductlevels for Hb increased rapidly over the first 4 hr with thehighest (ng/mg Hb ± SD) 3.7 ± 0.5 detected 24hr after OT administration at 50 mg/kg body wt. In contrast,adduct levels for pooled Alb samples increased from 0.7 ng/mgAlb at 2 hr to 2.5 ng/mg Alb at 4 hr, but were not detectable24 hr after dosing. Hb adducts showed a linear relationshipfor OT doses of 10, 20, 40, 50, and 100 mg/kg body wt. The Hbadduct t (11 days) was determined after a single 100 mg/kg OTdose. Hb adduct levels were quantifiable (1.3 ± 0.2 ng/mgHb) by HPLC/fluorescence 28 days after 100 mg/kg OT. AlthoughHb and Alb adducts differ in stability, a ratio of such OT adductsmay be useful in long-term industrial biomonitoring for evaluationof OT exposure.     

Anesthesia induction,emergence, and postoperative behaviors in children with attention‐deficit/hyperactivity disorders

Background/Aim: Given the increasing prevalence of attention‐deficit and attention‐deficit hyperactivity disorders (ADHD), anesthesiologists are now presented with a greater number of children who are diagnosed with these conditions. This prospective, observational study was designed to compare anesthesia induction, emergence, and postoperative behaviors in children with and without ADHD. Methods/Materials: The sample included 268 children, 4–17 years of age undergoing elective surgery with a confirmed diagnosis of ADHD. A cohort of children without ADHD, matched for age, gender, and procedure served as controls. Preoperative cooperation, induction, and emergence behaviors were measured using established scales. Postoperative maladaptive behaviors were measured using a modified Post‐Hospital Behavioral Questionnaire that was administered via telephone 1 week after surgery. Results: Children with ADHD were significantly less cooperative at induction of anesthesia compared with controls (20.9% vs 10.6% respectively, P = 0.001). Although some control children exhibited an increase in maladaptive behaviors postoperatively, these behaviors were significantly greater among children with ADHD. In particular, relative to their normal behaviors, children with ADHD had greater difficulties in concentration and decision‐making; were more disobedient, impulsive, fidgety, had poor appetite; were difficult to talk to; and exhibited an increase in temper tantrums following surgery. Conclusions: This is the first prospective study to our knowledge that has examined the perioperative and postoperative behaviors of children with ADHD compared to those without this disorder. These results are important in alerting anesthesiologists, parents, and teachers to the potential for difficulties during induction of anesthesia and postoperative behavioral problems at home and in school, respectively.     

Globin-methionine complexes formed during labelling studies

Summary. In implementing globin synthetic measurements using our recently described technique of Cellogel separation of ³⁵S-methionine-labelled globin chain we sometimes encountered aberrant results. We discovered the presence of prominent radioactive bands trailing both the alpha and beta globin chains. Such bands were not present when ³H-leucine served as a label. These bands were not duc to contaminants in the ³⁵S-methionine. Their formation could be prevented by including in the incubating mixture 1 mM cystine, cysteine or homocysteine. The bands could not be removed by trichloracetic acid or acid acetone precipitation but did disappear almost entirely after prolonged dialysis against a urea-containing buffer. The trailing bands appear to represent the result of the firm, but not covalent, binding of methionine to globin during the protein synthetic process. Since methionine is commonly used as a label for newly synthesized protein, this phenomenon may be important not only in the investigation of globin synthesis, but also in the study of the synthesis of other proteins.     

Shortened sleep duration does not predict obesity in adolescents

Obesity continues to be a major public health issue. In adolescents, there are limited studies on the relationship between obesity and sleep duration. We found hypothesized that an average sleep duration of <6 h in adolescents was associated with obesity. Data were from the National Longitudinal Study of Adolescent Health (ADD Health); a survey of 90 000 youths, aged 12–18 years; surveyed in several waves. The sample population for our study was 13 568. Weighted multiple logistic regression was used to identify the relationship between obesity at Wave II and sleep duration, having adjusted for skipping breakfast ≥ 2/week; race, gender, parental income, TV ≥ 2 h per day, depression, and obesity at Wave I. At Wave I, the mean age was 15.96 ± 0.11 years; mean sleep hours were 7.91 ± 0.04. At Waves I and II, respectively, 10.6 and 11.2% of adolescents were obese. Adjusted analyses suggest that the effect of shortened sleep duration in Wave I was not significantly predictive of obesity in Wave II (P < 0.218). Longitudinally, depression and TV ≥ 2 h per day at Wave I was associated with a higher risk of obesity at Wave II in adjusted analyses. Depressed adolescents were almost twice as likely to be obese (OR = 1.84, 95% CI = 1.25–2.72); adolescents who watched TV ≥ 2 h per day were 37% more likely to be obese (OR = 1.37, 95% CI = 1.09–1.72). Environmental factors including TV ≥ 2 h per day and depression were significantly associated with obesity; shortened sleep duration was not. Future longitudinal studies in adolescents are needed to determine whether timing of television watching directly influences sleep patterns and, ultimately, obesity.