Superiority of manual disinfection using pre-soaked wipes over automatic UV-C radiation without prior cleaning.

BACKGROUND: The efficacy of ultraviolet C (UV-C) radiation against a broad spectrum of micro-organisms has been demonstrated in several studies, but differences in the specific doses and the extent of microbial reduction were found. Furthermore, the conditions of laboratory tests differ greatly from reality, such that efficacy achieved in tests may not necessarily be assumed in reality. Consequently, it is important to investigate the effectiveness of UV-C in representative field trials. The aim was therefore to develop and establish a field test to evaluate automatic UV-C in comparison to manual disinfection. METHODS: Before and after disinfection, samples were repeatedly collected from naturally highly contaminated surfaces using the swab technique to obtain representative data sets for disinfected and non-disinfected surfaces. Subsequently, the log reduction values (LRV) and the disinfection success were evaluated for UV-C radiation and full compliant manual disinfection using alcohol-based wipes. RESULTS: Surfaces that are naturally contaminated with bacteria on a regular and nearly uniform basis have been identified as particularly suitable for field testing. Mean contamination was reduced from 23.3 to 1.98 cfu/cm2 (LRV 0.9) and 29.7 to 0.26 cfu/cm2 (LRV 1.2) for UV-C and manual disinfection, respectively. UV-C disinfection achieved 75.5% successful disinfected surfaces, whereas manual disinfection showed 98.1%. CONCLUSIONS: Full compliant manual disinfection showed slightly higher LRVs and disinfection success than automatic UV-C disinfection. Successful, operator-independent UV-C disinfection still has the potential to improve disinfection performance in addition to manual disinfection.

Tolerance of clinical vancomycin-resistant Enterococcus faecium isolates against UV-C light from a mobile source.

BACKGROUND: Admission to a room previously occupied by patients carrying environmentally robust pathogens implies an increased risk of acquiring those pathogens. Therefore, 'No-touch' automated room disinfection systems, including devices based on UV-C irradiation, are discussed to improve terminal cleaning. It is still unclear if clinical isolates of relevant pathogens behave differently under UV-C irradiation compared to laboratory strains used in the approval process of disinfection procedures. In this study we analysed the susceptibility of well characterized clonally divergent vancomycin-resistant enterococci (VRE) strains, including a linezolid-resistant isolate, against UV-C radiation. METHODS: Susceptibility against UV-C of ten clonally divergent clinical isolates of VRE was determined in comparison to the commonly used test organism Enterococcus hirae ATCC 10541. Ceramic tiles contaminated with 105 to 106 colony forming units/25 cm² of the different enterococci were positioned at a distance of 1.0 and 1.5 m and irradiated for 20 s, resulting in a UV-C dose of 50 and 22 mJ/cm², respectively. Reduction factors were calculated after quantitative culture of the bacteria recovered from treated and untreated surfaces. RESULTS: Susceptibility to UV-C varied considerably among the strains studied, with the mean value of the most robust strain being up to a power of ten lower compared to the most sensitive strain at both UV-C doses. The two most tolerant strains belonged to MLST sequence types ST80 and ST1283. The susceptibility of the laboratory strain E. hirae ATCC 10541 ranged between the most sensitive and most tolerant isolates for both irradiation doses. However, for UV-C dose of 22 mJ/cm², the reduction of the most tolerant isolate of ST1283 was statistically significantly lower compared to E. hirae ATCC 10541. The most susceptible strains belonged to the MLST sequence types ST117 and ST203. CONCLUSIONS: These results indicate that UV-C doses reported in the literature are sufficient for the reduction of commonly used reference strains of enterococci but could be insufficient for the reduction of tolerant patient VRE-isolates in a hospital setting. Therefore, for future studies, the most tolerant clinical isolates should be used to validate automated UV-C devices or longer exposure times should be expected to ensure efficacy in the real world.

Superior hypogastric plexus block for chronic pelvic pain in the presence of endometriosis: CT techniques and results.

PURPOSE: To evaluate the use of superior hypogastric plexus block with computed tomographic (CT) guidance in patients with endometriosis and chronic pelvic pain. MATERIALS AND METHODS: Seven blocks were performed on an outpatient basis in five women with endometriosis and pelvic pain. In the first four patients, one or two 20-gauge, 15-cm needles were placed anterior to the spine at the common iliac bifurcation from a posterior approach. In the fifth patient, the block was performed from an anterior approach with a single needle. RESULTS: One procedure resulted in mild pain relief, three in considerable pain relief, one in complete midline pain relief with no change in the lateral pain, and one in complete pain relief. One procedure was terminated because anesthetic was injected into the peritoneal cavity. There were no other complications. CONCLUSION: CT-guided superior hypogastric plexus block is easily performed and can be used to assess whether chronic pelvic pain can be attenuated by blocking the superior hypogastric plexus.

Drug interactions of clinical significance with opioid analgesics.

Opioid analgesics and other drugs interact through multiple mechanisms, resulting in pharmacological effects that depend upon the pharmacodynamic action studied, the interacting agents and the route of administration. Many interactions result from induction or inhibition of the hepatic cytochrome P450 mono-oxygenase system. The elimination of opioids is largely dependent on hepatic metabolism, and drug interactions involving this mechanism can therefore be clinically significant. Antibiotics are often used concomitantly with opioids in patients undergoing medical or surgical procedures; the best documented metabolic interactions are with erythromycin and rifampicin (rifampin). Erythromycin increases and rifampicin decreases the effects of opioids. Cimetidine may increase the effects of opioids by increasing their duration of action; there have been no documented cases of interactions with ranitidine. Carbamazepine, phenytoin and the barbiturates can enhance the metabolism of opioids that rely on hepatic metabolism. Other pharmacokinetic interactions include those with benzodiazepines, tricyclic antidepressants, phenothiazines and metoclopramide. Interactions involving pharmacodynamic mechanisms are more common than pharmacokinetic ones. Such interactions are manifested clinically as as a summation (additive or synergistic) of similar or opposing pharmacological effects on the same body system. Idiosyncratic interactions also occur, the mechanisms of which have not been proven to be solely modulated by either pharmacokinetic or pharmacodynamic means. The knowledge of particular opioid-drug interactions, and the causative pharmacokinetic, pharmacodynamic, and idiosyncratic mechanisms, allows for the safer administration of opioid analgesics.