Management of anorectal foreign bodies: a cause of obscure anal pain

BACKGROUND: Few patients with anorectal foreign bodies will freely admit to transanal introduction. The results of long-term follow-up in these patients have been sparse. METHODS: Data from April 1989 to April 1997 were extracted from a prospective computerized database. The clinical features and the results of a departmental management protocol for anorectal foreign bodies were analysed. In addition, long-term outcomes were obtained by telephone interview. RESULTS: Thirty patients (25 men, 5 women) with a mean age of 46 (range 16-72) years) were treated for this condition. While 10 patients (33.3%) admitted to transanal insertion, the remaining 20 (66.7%) complained of anal pain. Among the latter, the foreign body was subsequently found on routine digital rectal examination in nine patients (45%), on X-ray in nine (45%) and it was passed out unexpectedly after fleet enema in two (10%). Factors which raised suspicion for X-rays included atypical gender behaviour, lax anal sphincters and bloody or mucoid rectal discharge. Transanal recovery was successful with sedation in 12 (40%), general anaesthesia in 13 (43.3%), and laparotomy was needed in three (10%; which included one perforated bowel at presentation). There were two complications (6.7%; one minor rectal abrasion and one bronchopneumonia). There was no long-term faecal incontinence or re-impaction of foreign bodies at 63 (range 8-96) months of follow-up. CONCLUSIONS: Foreign bodies should be suspected in patients with obscure anal pain. Judicious transanal extraction under sedation or general anaesthesia was usually successful with minimal short- and long-term complications.     

Development of commissural neurons in the wallaby (Macropus eugenii)

We have examined the development of the laminar and areal distribution of cortical commissural neurons in a marsupial mammal, the wallaby Macropus eugenii. In this species, commissural axons approach the major cerebral commissure, the anterior commissure, via either the internal capsule or the external capsule and first cross the midline at postnatal day 14 (P14). By retrogradely labelling these axons with 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine (DiI) at P15, we show here that the cell bodies of these neurons are restricted to a region of cortex adjacent to the rhinal fissure. Most of these labelled neurons are located in the compact cell zone of the cortical plate, with only a few labelled cells found in the zone of loosely packed cells deep to this layer. Over the subsequent 66 days, commissural neurons are found progressively more dorsally, rostrally, and caudally, so that, by P80, they are present throughout the extent of the neocortex. At this age, they are mainly pyramidal in morphology and form a single band within the deeper part of layer 5 of the developing cortex. From P80 to adulthood, the distribution of commissural neurons has been assessed in the visual cortex by using retrograde transport of horseradish peroxidase. At P80, labelled neurons with immature pyramidal morphology are present throughout the occipital cortex; as in DiI material, somata are located in deep layer 5. At P165, previously shown to be the age when commissural axon numbers peak, widespread labelling is present in the occipital region, with labelled cells now found in two bands corresponding to layers 3 and 5. After this age, neurons become more restricted in distribution, so that, by adulthood, commissural neurons are no longer apparent throughout area 17 but are restricted to a localised region around the area 17/18 boundary. Within this region, labelling is still present in layers 3 and 5 but is more dense in layer 3. The gradual restriction of commissural fields seen here in the wallaby is similar to that reported in the neocortex in many eutherians. These findings also support studies in eutheria, suggesting that subplate neurons do not appear to play a major role in commissural development.     

A note on sample size determination for bioequivalence studies with high-order crossover designs

Similar to Liu and Chow, approximate formulas for sample size determination are derived based on Schuirmann's two one-sided tests procedure for bioequivalence studies for the additive and the multiplicative models under various higher order crossover designs for comparing two formulations of a drug product. The higher order crossover designs under study include Balaam's design, the two-sequence dual design, and two four-period designs (with two and four sequences), which are commonly used for assessment of bioequivalence between formulations. The derived formulas are simple enough to be carried out with a pocket calculator. The number of subjects required for each of the four higher order designs are tabulated for selected powers and various parameter values.     

Surgical metabolism

Trauma, operative interventions, infection and other disturbances of homeostasis lead to a uniform reaction of the body, namely release and activation of hormones and cytokines. Profound alterations of substrate flow result, with mobilization of energy stores and degradation of structural and functional proteins of vital organs like the gut mucosa. Due to these reactions the energy demands of the organs are met and energy-consuming synthesis of substrates is indicated. Clinically, hypermetabolism, hyperglycemia, lipolysis and increased urea production with negative nitrogen balance can be observed. The metabolic reactivity is reached by an increased substrate cycling. To avoid negative consequences such as organ dysfunction, a rational situation-adapted substrate supply is warranted as well as reduction of catabolic stimuli and stimulation of anabolic factors. The metabolic care of the surgical patient is still a basic and important task.