Volume Dependence of High-Frequency Respiratory Mechanics in Healthy Adults

Respiratory system input impedance (Zrs) at low to medium frequencies below 100 Hz, and study of its volume dependence, have been used extensively to quantify airway and tissue mechanics. Zrs at high oscillation frequencies including the first antiresonant frequency (far,1) may contain important information about airway mechanics. Changes in high-frequency Zrs with lung volume have not been studied. The volume-dependent behavior of high-frequency Zrs, specifically far,1 and respiratory system resistance at first antiresonance (Rrs(far,1)), was characterized in 16 healthy adults. Zrs was measured with a forced oscillation signal (5–302.5 Hz) through a wavetube setup. To track Zrs, subjects performed slow deep inspiratory and expiratory maneuvers over 30-s measurements, during which average impedance was calculated over 0.4-s intervals, with successive overlapping estimates every 0.156 s. Flow was measured using a pneumotachometer and integrated to obtain volume. Transpulmonary pressure dependence (Ptp) of Zrs was separately determined in five subjects. Both far,1 and Rrs(far,1) decreased with increasing lung volume and Ptp, consistent with an increase in airway caliber and decreased airway wall compliance as volume increased. These characterizations provide insight into airway mechanics, and are furthermore a necessary first step toward determining whether volume dependence of the first antiresonance is altered in disease.     

Basic emotion profiles in healthy, chronic pain, depressed and PTSD individuals

Objectives: To compare self‐reports of five basic emotions across four samples: healthy, chronic pain, depressed and post‐traumatic stress disorder (PTSD), and to investigate the extent to which basic emotion reports discriminate between individuals in healthy or clinical groups. Methods: In total, 439 participants took part in this study: healthy (n = 131), chronic pain (n = 220), depressed (n = 24) and PTSD (n = 64). The participants completed the trait version of the Basic Emotion Scale. Basic emotion profiles were compared both within each group and between the healthy group and each of the three other groups. Discriminant analysis was used to assess the extent to which basic emotions can be used to classify the participants as belonging to the healthy group or one of the clinical groups. Results: In the healthy group, happiness was experienced more than any other basic emotion. This was not found in the clinical groups. In comparison to the healthy participants, the chronic pain group experienced more fear, anger and sadness, the depressed group reported more sadness and the PTSD group experienced all of the negative emotions more frequently. Discriminant analysis revealed that happiness was the most important variable in determining whether an individual belonged to the healthy group or one of the clinical groups. Anger was found to further discriminate between depressed and chronic pain individuals. Conclusion: The findings demonstrate that basic emotion profile analysis can provide a useful foundation for the exploration of emotional experience both within and between healthy and clinical groups. Copyright © 2011 John Wiley & Sons, Ltd. Key Practitioner Message: ? More frequent experiences of happiness relative to discrete negative emotions most clearly discriminate between individuals in healthy and clinical groups. More frequent anger experiences further discriminate between individuals with chronic pain and those with depression while disgust levels help discriminate between those with post‐traumatic stress disorder (PTSD) and depression. ? More frequent experiences of high arousal negative emotions—fear, anger and disgust—are characteristic of individuals with PTSD. ? Fear is the most frequently experienced negative emotion in both healthy and clinical groups. Higher levels of fear compared with other discrete negative emotions are not necessarily an indicator of psychopathology. Consideration of emotional profiles more generally and the relative frequency with which happiness is experienced relative to negative emotions may be more useful in delineating between healthy individuals and those with chronic pain, depression or PTSD.     

A rapid precurarization technique using rocuronium

Purpose

To evaluate a rapid and time-saving precurarization technique using rocuronium to prevent succinylcholine-induced myalgia.

Method

In a prospective, double blind randomized study, 42 ASA 1–2 patients were assigned to one of three pretreatment groups: 0.01 ml · kg^?1 normal saline, 0.1 mg · kg^?1 atracurium, and 0.1 mg · kg^?1 rocuronium. Anaesthesia commenced with 1.5 μg · kg^?1 fentanyl and 0.5 mg · kg^?1 lidocaine at time zero. Pretreatment was administered 60 sec later, followed by 2.5 mg · kg^?1 propofol. At 90 sec, 1.5 mg · kg^?1 succinylcholine was injected and 30 sec later, the trachea was intubated and the ease of intubation was graded. The patient was observed for the presence and severity of fasciculations. Myalgias were recorded on postoperative days 1, 2 and 7.

Results

The incidence of fasciculations in the rocuronium group (21.4%) was lower (P < 0.001) than atracurium (78.5%) or placebo (92.8%) groups. On postoperative day 1, the incidence of postoperative myalgia in the rocuronium group (14.2%) was less than the placebo group (78.2%;P < 0.002) and atracurium group (85.7%;P < 0.001). The incidence of myalgia in the rocuronium group (7.1%) was lower than in the placebo group (78.5%;P < 0.001) but not different from the atracurium group (42.8%;P = 0.077) on postoperative day 2. On postoperative day 7, there was no difference among the three groups. Fasciculations were related to post-operative myalgia. There was no difference in intubating conditions among the three groups.

Conclusion

Rocuronium pretreatment given just before induction of anaesthesia with propofol reduces fasciculations and succinylcholine-induced myalgia.     

Graduate medical education in Ireland: a profile of the first cohort of students

Background  The first graduate-entry programmes to Irish medicine were established at the Royal College of Surgeons in Ireland (RCSI) and the University of Limerick (UL) in 2007. There were over 400 applications across both institutions and 306 people sat a special aptitude test (GAMSAT) in Ireland in 2007. Ultimately, 61 Irish/EU students were admitted to one or other programme. Aims and methods  We describe the demographic profile, academic background and aggregated GAMSAT performance of 306 people who sat GAMSAT in Ireland in 2007 and of the 61 people admitted to the RCSI/UL programmes. Results  While more females than males sat GAMSAT, slightly more males were admitted. Over 90% of those admitted were aged in their 20s, almost 20% had a higher degree and they came from a wide range of academic backgrounds. Conclusions  Among others, this information should be of interest to prospective students and to government policy makers.     

Non-vital immature permanent incisors: factors that may infIuence treatment outcome

Finucane D, Kinirons MJ. Non-vital immature permanent incisors: factors that may influence treatment outcome. Endod Dent Traumatol 1999; 15: 273–277. © Munksgaard, 1999.
Abstract — This study examines the treatment of non-vital immature permanent incisors using the calcium hydroxide apexification tecnique. The objectives of the present study were to determine the speed and location of bamer formation and those factors discernible at presentation and during treatment which may be related to it. Forty-four non-vital immature incisors undergoing calcium hydroxide apexification were reviewed in detail. All cases were reviewed every 8–12 weeks for up to 18 months, or until apexification occurred. Details of the time and nature of the injuries and treatment were recorded. The degree of apical development prior to treatment was assessed, and barrier formation, location and time were noted. Mean time to barrier formation was 34.2 weeks (range 13–67 weeks). The strongest predictor of rapid barrier formation was the rate of change of calcium hydroxide and a barrier also formed more rapidly in cases with narrower initial apical width. There was evidence of displacement and a higher mean time for barrier formation in half of the cases. The presence of an abscess was the weakest predictor of rapid barrier formation and the effect was not significant (P=0.280). The barrier was located at the apex in 28 cases (63.6%) and the distance from the barrier to the apex for the remaining 16 (36.4%) varied from 1 mm to 5 mm. The number of placements of calcium hydroxide varied from 1 to 4 with a mean of 1.9, and there was a higher mean number of calcium hydroxide placements in the cases where the barrier was located at the apex.