Morphological variation in the tropical anole, Anolis casildae (Squamata: Polychrotidae).

We describe morphological variation (scalation and coloration) observed among eight individuals of the Panamanian lizard species Anolis casildae. This variation was not observed in the holotype and aids in identification of this recently described species (originally described on the basis of a single, male specimen). This species occurs only in the Reserva Forestal Fortuna (Chiriquí Province) and the adjacent Bosque Protector Palo Seco (Bocas del Toro Province) in western Panama. Anolis casildae can be distinguished from all other Panamanian anole species via six features: (1) two enlarged superciliary scales (the first larger than the second); (2) an anterior nasal scale in contact with the rostral scale or separated from the rostral by one scale; (3) 6-8 sublabial scales to the center of the eye; (4) 3-4 scales between the supraobital semicircles; (5) unique coloration (4-6 oblique brown bands interspersed by blue-outlined yellow patches; dewlap is a dirty cream color with broad yellow scale rows irregularly interspersed with smaller emerald green scales) and (6) A. casildae occurs from 1,050 to 1,400 m in the Cordillera Central. We also compare our natural history observations of A. casildae to a similar large anole, A. frenatus, a species which we believe A. casildae to be closely related.

Low dose bupivacaine/fentanyl epidural infusions in labour and mode of delivery.

The aim of this study was to determine the effect on the instrumental delivery rate of two different concentrations of bupivacaine combined with fentanyl in epidural infusions during labour. Only primiparous women in whom a spontaneous vaginal delivery was anticipated, were included in the study. Those women receiving a higher concentration of bupivacaine and therefore a greater amount of local anaesthetic agent during labour were significantly more likely to have an instrumental delivery with Kielland's rotational forceps (p < 0.01). Those women receiving a lower concentration and smaller amount of bupivacaine were significantly more likely to have an instrumental delivery with Neville-Barnes forceps (p < 0.05). This provides evidence to support the theory that epidural analgesia may contribute to inadequate rotation of the presenting fetal part due to weakened pelvic floor muscles and that this is more likely to occur when higher concentrations of bupivacaine are used and a greater degree of motor block occurs.

Influence of tramadol on the ventilatory response to hypoxia in humans.

We studied the effect of tramadol on the ventilatory response to 7 min acute isocapnic hypoxia (SpO2 85.1 (SD 0.4)%) during steady mild hypercapnia (PE'CO2 0.7 kPa above normoxic baseline) in 14 healthy volunteers (seven male). The acute hypoxic response was measured before and 1 h after oral placebo or tramadol (100 mg). After tramadol, ventilation during mild hypercapnia (mean 11.28 litres min-1) was significantly less (P < 0.05) than during placebo baseline (13.93 litres min-1), tramadol baseline (14.63 litres min-1), or after placebo (14.95 litres min-1), confirming that tramadol has a small depressive effect on the hypercapnic ventilatory response. There was no significant difference in the hypoxic ventilation/SpO2 response (1 min-1 %-1) measured during the placebo baseline (0.99), placebo (1.18), tramadol baseline (0.78) or tramadol (0.68) runs. These data suggest that tramadol does not depress the hypoxic ventilatory response.