RESUMEN
Field surveys and laboratory studies were used to determine the role of substrata in habitat selection by young-of-the year winter flounder. A synoptic field survey of winter flounder and sediments in the Navesink River-Sandy Hook Bay estuarine system in New Jersey demonstrated that winter flounder distribution was related to sediment grain size. Analysis using a generalized additive model indicated that the probability of capturing 10-49 mm SL winter flounder was high on sediments with a mean grain diameter of =0.5 mm, while fish 50-95 mm were least likely to be collected on fine sediments and most commonly on sediments with a grain-size near 1.0 mm. In the laboratory, sediment preferences and the burying ability of winter flounder (15-69 mm SL) were tested by exposing fish in 10-mm size groups to a choice of azoic sediments of different sediment grain sizes. Smaller individuals (<40 mm SL) preferred fine-grained sediments while larger individuals (>/=40 mm SL) preferred coarse-grained sediments. Burying ability increased with size and all flounders avoided sediments that prevented burial. Subsequent laboratory experiments revealed that the presence of live prey (Mya arenaria) can over-ride sediment choice by winter flounder (50-68 mm SL) indicating the complexity of interrelated factors in habitat choice.
RESUMEN
Central venous catheters (CVCs) are widely used in critically ill patients in intensive care units. However, infectious complications are common and may limit their utility. We critically review the literature to determine the impact of CVC design and composition, insertion site selection, insertion procedures, care and removal of temporary CVCs on infectious complications. Relevant articles were identified and selected for review using a database search (Medline and manual of the English language literature) based upon study design and sample size with an emphasis on prospective randomized trials. To minimize infectious complications and maintain a reasonable cost-benefit ratio, we recommend: i) use a single lumen catheter unless clear indications for a multi-lumen catheter exist; ii) insert the catheter via the subclavian vein if no relative contraindication exists (bleeding diathesis, positive pressure ventilation); iii) disinfect the insertion site employing sterile technique; iv) apply a dry, sterile dressing and change the dressing every other day; v) inspect the insertion site for signs of infection and remove the catheter if pus is present; vi) if a catheter-related infection is suspected, change the catheter over a guidewire and culture the distal segment. The replacement catheter should be removed if an original catheter segment culture is positive.