Colistin combination therapy improves microbiologic cure in critically ill patients with multi-drug resistant gram-negative pneumonia.

Currently, in vitro synergy with colistin has not translated into improved clinical outcomes. This study aimed to compare colistin combination therapy to colistin monotherapy in critically ill patients with multi-drug resistant gram-negative (MDR-GN) pneumonia. This was a retrospective analysis of critically ill adult patients receiving intravenous colistin for MDR-GN pneumonia comparing colistin combination therapy to colistin monotherapy with a primary endpoint of clinical cure. Combination therapy was defined by administration of another antibiotic to which the MDR-GN pathogen was reported as susceptible or intermediate. Ninety patients were included for evaluation (41 combination therapy and 49 monotherapy). Baseline characteristics were similar between groups. No difference in clinical cure was observed between combination therapy and monotherapy in univariate analysis, nor when adjusted for APACHE II score and time to appropriate antibiotic therapy (57.1 vs. 63.4 %, adjusted OR 1.15, p = 0.78). Microbiological cure was significantly higher for combination therapy (87 vs. 35.5 %, p < 0.001). Colistin combination therapy was associated with a significant improvement in microbiological cure, without improvement in clinical cure. Based on the in vitro synergy and improvement in microbiological clearance, colistin combination therapy should be prescribed for MDR-GN pneumonia. Further research is warranted to determine if in vitro synergy with colistin translates into improved clinical outcomes.

Pre-injury neuro-psychiatric medication use, alone or in combination with cardiac medications, may affect outcomes in trauma patients.

BACKGROUND: Recent review of older (≥45-years-old) patients admitted to our trauma center showed that more than one-third were using neuro-psychiatric medications (NPMs) prior to their injury-related admission. Previously published data suggests that use of NPMs may increase patients' risk and severity of injury. We sought to examine the impact of pre-injury NPM use on older trauma patients' morbidity and mortality. MATERIALS AND METHODS: Retrospective record review included medication regimen characteristics and NPM use (antidepressants-AD, antipsychotics-AP, anxiolytics-AA). Hospital morbidity, mortality, and 90-day survival were examined. Comparisons included regimens involving NPMs, further focusing on their interactions with various cardiac medications (beta blocker - BB; angiotensin-converting enzyme inhibitor/angiotensin receptor blocker - ACE/ARB; calcium channel blocker - CCB). RESULTS: 712 patient records were reviewed (399 males, mean age 63.5 years, median ISS 8). 245 patients were taking at least 1 NPM: AD (158), AP (35), or AA (108) before injury. There was no effect of NPM monotherapy on hospital mortality. Patients taking ≥3 NPMs had significantly lower 90-day survival compared to patients taking ≤2 NPMs (81% for 3 or more NPMs, 95% for no NPMs, and 89% 1-2 NPMs, P < 0.01). Several AD-cardiac medication (CM) combinations were associated with increased mortality compared to monotherapy with either agent (BB-AD 14.7% mortality versus 7.0% for AD monotherapy or 4.8% BB monotherapy, P < 0.05). Combinations of ACE/ARB-AA were associated with increased mortality compared to ACE/ARB monotherapy (11.5% vs 4.9, P = 0.04). Finally, ACE/ARB-AD co-administration had higher mortality than ACE/ARB monotherapy (13.5% vs 4.9%, P = 0.01). CONCLUSIONS: Large proportion of older trauma patients was using pre-injury NPMs. Several regimens involving NPMs and CMs were associated with increased in-hospital mortality. Additionally, use of ≥3 NPMs was associated with lower 90-day survival.

In vitro assessment of red-cell concentrates in SAG-M filtered through the MacoPharma P-CAPT prion-reduction filter.

This study investigated whether filtration of leucodepleted red cells in SAG-M through the P-CAPT filter in order to prevent the potential risk of vCJD infection associated with prion transmission through transfusion has any deleterious effect on red-cell quality. Bottom-and-top SAG-M leucodepleted red-cell concentrates (24 units) were prion-reduction filtered on the day following collection, with half of the units undergoing irradiation on day 14. A control group (12 units) was not prion filtered. Units were sampled at 7-day intervals up to day 35 and tested using standard measures of red-cell quality as well as prothrombin content (to examine prion filter efficacy). Haemoglobin loss per unit was approximately 9 g and in some cases levels were below standard specification (40 g). Haemolysis increased significantly after filtration [0.01 (0.00-0.05) vs. 0.23 (0.07-0.52, p<0.001)]. Prothrombin levels were reduced 41.6-fold compared to leucodepleted red-cell units. Product specifications were within or close to routine acceptable levels. Owing to the reduction in haemoglobin levels below those specified, it may be preferable to reduce haemoglobin specification levels and transfuse more prion-filtered units rather than transfuse potentially unsafe blood product. The risk of transfusing more units with less haemoglobin should be offset against the risk of transfusing unfiltered blood.

Laboratory and clinical outcomes of pharmacogenetic vs. clinical protocols for warfarin initiation in orthopedic patients.

BACKGROUND: Warfarin is commonly prescribed for prophylaxis and treatment of thromboembolism after orthopedic surgery. During warfarin initiation, out-of-range International Normalized Ratio (INR) values and adverse events are common. METHODS: In orthopedic patients beginning warfarin therapy, we developed and prospectively validated pharmacogenetic and clinical dose refinement algorithms to revise the estimated therapeutic dose after 4 days of therapy. RESULTS: The pharmacogenetic algorithm used the cytochrome P450 (CYP) 2C9 genotype, smoking status, peri-operative blood loss, liver disease, INR values and dose history to predict the therapeutic dose. The R(2) was 82% in a derivation cohort (n = 86) and 70% when used prospectively (n = 146). The R(2) of the clinical algorithm that used INR values and dose history to predict the therapeutic dose was 57% in a derivation cohort (n = 178) and 48% in a prospective validation cohort (n = 146). In 1 month of prospective follow-up, the percent time spent in the therapeutic range was 7% higher (95% CI: 2.7-11.7) in the pharmacogenetic cohort. The risk of a laboratory or clinical adverse event was also significantly reduced in the pharmacogenetic cohort (Hazard Ratio 0.54; 95% CI: 0.30-0.97). CONCLUSIONS: Warfarin dose adjustments that incorporate genotype and clinical variables available after four warfarin doses are accurate. In this non-randomized, prospective study, pharmacogenetic dose refinements were associated with more time spent in the therapeutic range and fewer laboratory or clinical adverse events. To facilitate gene-guided warfarin dosing we created a non-profit website, http://www.WarfarinDosing.org.