A TRIAL OF PROPANIDID (FBA.1420): A NEW ULTRASHORT-ACTING ANAESTHETIC

Propanidid, a new intravenous anaesthetic derived from eugenol,has been employed for dental anaesthesia in 302 unpremedicatedpatients. In about half the patients propanidid was used asthe sole anaesthetic agent; a dose of 5 to 7 mg/kg (dependingon type of patient and number and ease of extractions) generallyallowed satisfactory extraction of a few teeth. Recovery ofconsciousness, orientation and ambulation were rapid. In patientsrequiring extraction of larger numbers of teeth and in somepatients in whom propanidid alone proved inadequate, nitrousoxide and oxygen supplementation was administered followingthe intravenous induction, and this provided adequate operatingconditions except in "resistant" patients in whom a volatilesupplement was necessary. The advantages and shortcomings ofthis new agent are detailed.     

HEMOGLOBIN-OXYGEN AFFINITY IN HYPOPHOSPHATEMIC RICKETS

Abstract. In 14 patients with simple X–linked hypophosphatemic rickets, 5 were below the third percentile in height and 9 were between the third and twenty-fifth percentile. Although the mean serum inorganic phosphorus level was only 2.01±0.65 (normal range for all age groups is 3.8 to 6.0 mg/100 ml), both the mean values for red cell 2,3-diphosphoglycerate (2,3-DPG) and adenosine triphosphate (ATP) were normal at 4.78±1.23 and 1.02±0.17 μmol/ml of red blood cells respectively. Moreover, the mean P₅₀ value was normal at 26.4±0.9 mmHg. These normal oxygen transport data make unlikely any proposal that short stature seen in these patients is secondary to chronic tissue hypoxia. They also indicate that the intra-erythrocytic organic phosphate levels are maintained at normal levels despite profound chronic hypophosphatemia.     

An institutional experience with epidural analgesia in children and young adults undergoing cardiac surgery

Background: Allowing spontaneous respiration after cardiac surgery eliminates complications related to mechanical ventilation and optimizes cardiopulmonary interaction. Epidural analgesia has been proposed to promote early extubation after cardiac surgery. Objective: To identify the characteristics of patients with epidural analgesia and safety profiles with respect to the timing of extubation following cardiac surgery. Design and method: A retrospective chart review of patients who underwent cardiac surgery during a 5‐year period. Demographic, procedural, and perioperative variables were analyzed to investigate factors that affect the timing of extubation. Results: A total of 750 records were reviewed. The patients’ median age was 12 months, and 52% were infants (<1 year). Seventy‐five percent of the patients utilized cardiopulmonary bypass. The study population was classified into three groups according to the timing of extubation: 66% were extubated in the operating room or upon arrival at the PICU (Immediate), 15% were extubated within 24 h (mean, 10.8 h; 95% CI, 9.0–12.6) (Early), and 19% were extubated after 24 h (Delayed). For the Immediate and Early groups, multivariate logistic regression identified young age, increased cross‐clamp time, and inotrope score as independent risk factors for the need for mechanical ventilation. Postextubation respiratory acidosis (mean P_aCO₂, 50 mmHg; 95% CI, 49–51) was well tolerated by all patients. There were no neurologic complications related to the epidural technique. Conclusion: Epidural analgesia in children undergoing cardiac surgery provides stable analgesia without complications in our experience.     

Sun exposure modification programmes and their evaluation: a review of the literature

Epidemiological studies have demonstrated a causal link betweenexcessive sun exposure and skin cancer, leading to the developmentof primary and secondary prevention programmes. In countrieswhere there has been a significant increase in the incidenceof melanoma, large amounts of time, effort and money have beenspent on the design and implementation of programmes aimed atincreasing knowledge about the risks of excessive sun exposure,changing attitudes about the effect of tanning, promoting sunprotective behaviours, and modifying sun exposing behaviours.The majority of the evaluations of intervention programmes havefocused on changes in knowledge levels and attitudes, with comparativelylittle attention paid to the impact on sun-related behaviour.This article reviews the studies which have evaluated programmesdesigned to modify sun exposure. The evaluation studies aregrouped according to methodological design; they relate bothto programmes aimed at the general population as well as specificsub-groups such as schoolchildren and outdoor workers. The reviewdemonstrates the considerable variation in the degree of successachieved by the programmes. Attention is drawn to the need forinformation on costs, and for the greater use of randomisedcontrolled trials. It also shows that the evaluation of theseprogrammes has been quite limited. The review addresses thedesign issues involved, and ways of improving evaluation aresuggested.     

Olestra Postmarketing Surveillance Study: Design and Baseline Results from the Sentinel Site

Objective To describe the design of the Olestra Postmarketing Surveillance Study (OPMSS) and to present baseline results from the sentinel site. The purpose of the OPMSS is to monitor consumption patterns of olestra-containing snacks and to determine whether consumption affects nutritional status.Design The OPMSS combines repeated cross-section, random-digit dial telephone surveys before and after the market release of olestra-containing foods as well as intensive dietary and clinical assessments on a subsample of survey participants.Subjects Data are from baseline telephone (n=1,962) and clinical (n=1,069) assessment of participants (aged 18 to 74 years) in the Marion County, Indiana, sentinel site. Mean age of participants in the telephone survey was 43.2 years; 19% of respondents were black and 29% had completed college.Statistical analysis Analyses examined associations among savory snack use, fruit and vegetable consumption, and demographic and health-related characteristics. Data from the telephone survey were adjusted to be representative of the Marion County population.Results Almost 96% of the population surveyed had eaten savory snacks in the month before the survey: 74% had eaten regular-fat, 26% fat-reduced, and 78% nonfat types. Total snack consumption did not differ by gender, education, or race. Residents younger than 35 years ate snacks 16 times a month compared with 12 times a month among older residents. Types of snacks consumed differed markedly by demographic characteristics. Male, younger, and less educated residents ate more regular-fat snacks; female, white, and college-educated residents ate more nonfat snacks. In general, residents practicing healthful behaviors, including not smoking, eating fruits and vegetables, and exercising, also ate fewer regular-fat and more nonfat snacks. Fat intake was also related linearly to use of snack foods, ranging from 33.2% of energy among those consuming 1 serving per month or less to 36.8% among those consuming 20 or more servings per month.Applications/conclusions Procedures for recruitment and nutrition assessment appear adequate for evaluating the impact of olestra consumption on nutritional status. Nutritionists should be aware that there is potential for relatively high olestra consumption, given that almost 35% of Marion County residents eat snack foods at least 20 times a month. Consumers eating at least 20 servings of snacks per month derived more than 12% of their total energy and fat from snack foods, which suggests that substituting olestra snacks could substantially reduce intakes of fat and energy. J Am Diet Assoc. 1998;98:1290–1296.     

Advances in Catheter Ablation use of Unipolar Electrograms

Ventricular tachycardia in man can be eliminated by relatively small lesions in the reentrant circuit. This report includes a review of available energy sources, and methods for localizing arrhythmias. Methods to assure contact and prevent perforation using low frequency electrograms are presented including the new finding of reverse ST deflection with contact. Experience with laser energy in dogs showed discrete homogenous lesions. When compared with DC shock the animals showed far less arrhythmia and the lack of far field effect greatly reduced echo abnomalities in the post shock period. Studies with radiofrequency show ability to produce localized lesions similar to the laser but with a more flexible catheter. Localization requires a correlation of techniques including pacemapping, activation maps and pacing during tachycardia. Early activation (< −60 ms) at times 180–320 ms, with comparable pace to QRS during tachycardia with no change in morphology best localized the slow zone of the reentrant circuit. The low frequency unipolar electrogram from the tip and immediately proximal electrode revealed contact with ST deviation. The distal deviation was always greater than the proximal RV free wall and posterior basal produced depression rather than elevation of the electrogram. While the mechanism of ST reversal with contact is not understood and may relate to the type of indifferent reference used (Wilson central terminal), the ST depression reveals the same information about contact that elevation does in most other areas of the heart studied in our patients.