Population kinetics of gentamicin in neonates

A population kinetic analysis was carried out on sparse plasma gentamicin (GE) concentration data from 469 neonates obtained as part of a routine therapeutic drug monitoring (TDM) programme in the hospital neonatology unit.The best predictors of the kinetic parameters of the monoexponential model, volume of distribution (Vd) and clearance (CL), were the weight (WT) and gestational age (GA). Vd of the neonates was only related to WT, whereas the half-life was only related to the GA.     

Gunther Tulip Retrievable Inferior Vena Caval Filters: Indications,Efficacy, Retrieval,and Complications

Purpose We evaluated the Gunther Tulip (GT) retrievable inferior vena cava (IVC) filter with regard to indications, filtration efficacy, complications, retrieval window, and use of anticoagulation. Method A retrospective study was performed of 147 patients (64 men, 83 women; mean age 58.8 years) who underwent retrievable GT filter insertion between 2001 and 2005. The indications for placement included a diagnosis of pulmonary embolism or deep venous thrombosis with a contraindication to anticoagulation (n = 68), pulmonary embolism or deep venous thrombosis while on anticoagulation (n = 49), prophylactic filter placement for high-risk surgical patients with a past history of pulmonary embolism or deep venous thrombosis (n = 20), and a high risk of pulmonary embolism or deep venous thrombosis (n = 10). Forty-nine of the 147 patients did not receive anticoagulation (33.7%) while 96 of 147 patients did, 82 of these receiving warfarin (56.5%), 11 receiving low-molecular weight heparins (7.58%), and 3 receiving antiplatelet agents alone (2.06%). Results Filter placement was successful in 147 patients (100%). Two patients had two filters inserted. Of the 147 patients, filter deployment was on a permanent basis in 102 and with an intention to retrieve in 45 patients. There were 36 (80%) successful retrievals and 9 (20%) failed retrievals. The mean time to retrieval was 33.6 days. The reasons for failed retrieval included filter struts tightly adherent to the IVC wall (5/9), extreme filter tilt (2/9), and extensive filter thrombus (2/9). Complications included pneumothorax (n = 4), failure of filter expansion (n = 1), and breakthrough pulmonary embolism (n = 1). No IVC thrombotic episodes were recorded. Discussion The Gunther Tulip retrievable filter can be used as a permanent or a retrievable filter. It is safe and efficacious. GT filters can be safely retrieved at a mean time interval of 33.6 days. The newly developed Celect filter may extend the retrieval interval.     

3He MR imaging of porcine paranasal sinuses

RATIONALE AND OBJECTIVES: The aim of this study was to test the effectiveness of laser-hyperpolarized helium 3 (3He) as a contrast agent for magnetic resonance (MR) imaging of porcine paranasal sinuses. MATERIALS AND METHODS: Imaging experiments were conducted on the heads of four 50-kg Yorkshire pigs after open sinus surgery was performed. Paranasal sinus MR images were obtained with laser-polarized 3He gas produced through the spin-exchange method. The gas was delivered into the sinuses through two 14-gauge plastic catheters inserted in the nostrils. The 3He MR images were then compared with spatially correlated proton MR images. RESULTS: The porcine paranasal sinuses were adequately depicted by MR imaging with hyperpolarized 3He. The signal intensity of the paranasal sinuses on the 3He MR images was related to the size of the opening joining the sinuses to the nasal cavity and was clearly time dependent. CONCLUSION: Hyperpolarized 3He MR imaging may be particularly useful for identifying the anatomic configuration of the paranasal sinuses, as well as for assessing sinus aeration. Further study of the time-dependence of 3He signal intensity may help increase understanding of gas exchange in the sinuses.     

Endovascular repair of posterior communicating artery aneurysms,associated with oculomotor nerve palsy: A review of nerve recovery

Purpose

Oculomotor nerve palsy (ONP) is often the presenting symptom in patients with posterior communicating artery (PCOMM) aneurysms with variable recovery of oculomotor nerve function following treatment. In this study we report the ophthalmologic outcome of 20 patients treated by endovascular coiling for PCOMM aneurysm-induced ONP.

Methods

We performed 230 PCOMM aneurysm endovascular coilings between the years 2006 and 2011, of which 20 cases presented with ONP. We recorded the degree of nerve recovery – complete, partial or none – while also documenting other predictive factors, such as degree of pre-intervention nerve deficit, presence of subarachnoid haemorrhage (SAH), size and location of the PCOMM aneurysm and length of follow-up.

Results

Of the 20 patients, 9 (45%) presented with complete ONP and 11 (55%) with partial ONP. After an average follow-up period of 16 months, all patients achieved oculomotor nerve recovery; 9 (45%) patients had complete recovery and 11 (55%) patients had partial recovery. Of the 9 patients who presented with complete ONP, 5 (56%) patients made a complete recovery and 4 (44%) made a partial recovery. Of the 11 patients who initially presented with partial ONP, 4 (36%) made a complete recovery and 7 (64%) made a partial recovery. 7 (35%) patients also had a SAH, of whom 3 (43%) made a complete recovery with 4 (57%) making a partial recovery.

Conclusions

ONP can occur with PCOMM aneurysm with or without SAH. Endovascular coiling is an effective treatment for ONP due to PCOMM aneurysms.     

Incidence and patterns of polydrug use and craving for ecstasy in regular ecstasy users: an ecological momentary assessment study

BACKGROUND: Previous studies employing retrospective assessments methods found that regular ecstasy users frequently use alcohol, marihuana and other drugs in combination with ecstasy. METHODS: Twenty-two participants (13 males, 9 females) wore a wrist actigraph/data recorder to record real-time drug use and ecstasy craving for 6 weeks. Rates of alcohol and drug use on ecstasy use versus non-use nights, and before, during, and after ecstasy use were analyzed with generalized estimation equations (GEE). Craving was modeled with GEE and linear mixed models. RESULTS: Approximately 70% of ecstasy uses occurred on Friday or Saturday nights. No drug was significantly more likely to be used on ecstasy use nights than comparison Friday and Saturday nights. On nights ecstasy was used, in general across all drugs assessed, use was more likely before and during than after ecstasy intoxication, while alcohol use was also more likely before than during ecstasy intoxication. Though low overall, craving for ecstasy increased over 24 h before use and was higher on Friday nights of weeks ecstasy was used on weekends than weeks it was not used. CONCLUSIONS: Use of ecstasy on a particular night may not be associated with any greater likelihood of using any other intoxicating drug, and use of other drugs on nights involving ecstasy use may simply reflect a "natural history" of drug-use nights that begins with alcohol, progresses to more intoxicating drugs, and ends with little drug use. Confirmation of these findings awaits further advances in the application of ecological momentary assessment methodologies.