Minimal-invasive percutaneous reduction and transsacral screw fixation for U-shaped fractures

STUDY DESIGN Technical note and case series. OBJECTIVE To introduce an innovative minimal-invasive surgical procedure reducing surgery time and blood loss in management of U-shaped sacrum fractures. SUMMARY OF BACKGROUND Despite their seldom appearance, U-shaped fractures can cause severe neurological deficits and surgical management difficulties. According to the nature of the injury normally occurring in multi-injured patients after a fall from height, a jump, or road traffic accident, U-shaped fractures create a spinopelvic dissociation and hence are highly unstable. In the past, time-consuming open procedures like large posterior constructs or shortening osteotomies with or without decompression were the method of choice, sacrificing spinal mobility. Insufficient restoration of sacrococcygeal angle and pelvic incidence with conventional techniques may have adverse long-term effects in these patients. METHODS In a consecutive series of 3 patients, percutaneous reduction of the fracture with Schanz pins inserted in either the pedicles of L5 or the S1 body and the posterior superior iliac crest was achieved. The Schanz pins act as lever, allowing a good manipulation of the fracture. The reduction is secured by a temporary external fixator to permit optimal restoration of pelvic incidence and sacral kyphosis. Insertion of 2 transsacral screws allow fixation of the restored spinopelvic alignment. RESULTS Anatomic alignment of the sacrum was possible in each case. Surgery time ranged from 90 to 155 minutes and the blood loss was <50 mL in all 3 cases. Two patients had very good results in the long term regarding maintenance of pelvic incidence and sacrococcygeal angle. One patient with previous cauda equina decompression had loss of correction after 6 months. CONCLUSIONS Percutaneous reduction and transsacral screw fixation offers a less invasive method for treating U-shaped fractures. This can be advantageous in treatment of patients with multiple injuries.

Clinical outcome of patients with stable ischaemic heart disease as compared to those with acute coronary syndromes after percutaneous coronary intervention

Aims: To compare clinical outcomes after percutaneous coronary intervention (PCI) between patients with acute coronary syndromes (ACS) and those with stable ischaemic heart disease (SIHD) stratified by anatomic disease complexity (SYNTAX score). Methods and results: Patient-level data from three all-comers PCI trials were pooled. Patients (n=4,204) were stratified by clinical presentation (i.e., ACS or SIHD) and by SYNTAX score (i.e., lowest vs. two highest tertiles). The major adverse cardiac event (MACE) rates of patients with low-risk SIHD (n=531) and high-risk SIHD (n=1,066) were compared with ACS patients (n=2,607), respectively. At two years, the risk of MACE was higher for high-risk SIHD patients (OR 1.34, 95% CI: 1.08-1.66) and lower for low-risk SIHD patients (OR 0.61, 95% CI: 0.43-0.87) compared with ACS patients, respectively. This difference between high-risk SIHD patients and ACS patients was primarily driven by a higher risk of myocardial infarction (OR 1.64, 95% CI: 1.21-2.21), while there was no difference for cardiac death (OR 0.77, 95% CI: 0.49-1.21) or target lesion revascularisation (OR 1.21, 95% CI: 0.91-1.62). Conclusions: In this pooled analysis, the majority of patients undergoing PCI for SIHD (i.e., with SYNTAX score >8) had a higher risk of MACE than patients with ACS. Trial registration: URL: http://www.ClinicalTrials.gov; unique identifier: NCT00297661 (Sirtax), NCT00389220 (Leaders), NCT00114972 (Resolute-AC).

Intra- and postoperative complications of navigated and conventional techniques in percutaneous iliosacral screw fixation after pelvic fractures: Results from the German Pelvic Trauma Registry

Background: Percutaneous iliosacral screw placement following pelvic trauma is a very demanding technique involving a high rate of screw malpositions possibly associated with the risk of neurological damage or inadequate stability. In the conventional technique, the screw’s correct entry point and the small target corridor for the iliosacral screw may be difficult to visualise using an image intensifier. 2D and 3D navigation techniques may therefore be helpful tools. The aim of this multicentre study was to evaluate the intra- and postoperative complications after percutaneous screw implantation by classifying the fractures using data from a prospective pelvic trauma registry. The a priori hypothesis was that the navigation techniques have lower rates of intraoperative and postoperative complications. Methods: This study is based on data from the prospective pelvic trauma registry introduced by the German Society of Traumatology and the German Section of the AO/ASIF International in 1991. The registry provides data on all patients with pelvic fractures treated between July 2008 and June 2011 at any one of the 23 Level I trauma centres contributing to the registry. Results: A total of 2615 patients were identified. Out of these a further analysis was performed in 597 patients suffering injuries of the SI joint (187 � with surgical interventions) and 597 patients with sacral fractures (334 � with surgical interventions). The rate of intraoperative complications was not significantly different, with 10/114 patients undergoing navigated techniques (8.8%) and 14/239 patients in the conventional group (5.9%) for percutaneous screw implantation (p = 0.4242). Postoperative complications were analysed in 30/114 patients in the navigated group (26.3%) and in 70/239 patients (29.3%) in the conventional group (p = 0.6542). Patients who underwent no surgery had with 66/197 cases (33.5%) a relatively high rate of complications during their hospital stay. The rate of surgically-treated fractures was higher in the group with more unstable Type-C fractures, but the fracture classification had no significant influence on the rate of complications. Discussion: In this prospective multicentre study, the 2D/3D navigation techniques revealed similar results for the rate of intraoperative and postoperative complications compared to the conventional technique. The rate of neurological complications was significantly higher in the navigated group.

The effectiveness of a needleless intravenous system in prevention of percutaneous injury in two hospitals

This study assessed if hospital-wide implementation of a needleless intravenous connection system reduces the number of reported percutaneous injuries, overall and those specifically due to intravenous connection activities.^ Incidence rates were compared before and after hospital-wide implementation of a needleless intravenous system at two hospitals, a full service general hospital and a pediatric hospital. The years 1989-1991 were designated as pre-implementation and 1993 was designated as post-implementation. Data from 1992 were not included in the effectiveness evaluation to allow employees to become familiar with use of the new device. The two hospitals showed rate ratios of 1.37 (95% CI = 1.22-1.54, p $\le$.0001) and 1.63 (95% CI = 1.34-1.97, p $\le$.0001), or a 27.1% and a 38.6% reduction in overall injury rate, respectively. Rate ratios for intravenous connection injuries were 2.67 (95% CI = 1.89-3.78, p $\le$.0001) and 3.35 (95% CI = 1.87-6.02, p $\le$.0001), or a 62.5% and a 69.9% reduction in injury rate, respectively. Rate ratios for all non-intravenous connection injuries were calculated to control for factors other than device implementation that may have been operating to reduce the injury rate. These rate ratios were lower, 1.21 and 1.44, demonstrating the magnitude of injury reduction due to factors other than device implementation. It was concluded that the device was effective in reduction of numbers of reported percutaneous injuries.^ Use-effectiveness of the system was also assessed by a survey of randomly selected device users to determine satisfaction with the device, frequency of use and barriers to use. Four hundred seventy-eight surveys were returned for a response rate of 50.9%. Approximately 94% of respondents at both hospitals expressed satisfaction with the needleless system and recommended continued use. The survey also revealed that even though over 50% of respondents report using the device "always" or "most of the time" for intravenous medication administration, flushing lines, and connecting secondary intravenous lines, needles were still being used for these same activities. Compatibility, accessibility and other technical problems were reported as reasons for using needles for these activities. These problems must be addressed, by both manufacturers and users, before the needleless system will be effective in prevention of all intravenous connection injuries. ^

High intestinal cholesterol absorption is associated with cardiovascular disease and risk alleles in ABCG8 and ABO: evidence from the LURIC and YFS cohorts and from a meta-analysis.

OBJECTIVES This study sought to determine whether high intestinal cholesterol absorption represents a cardiovascular risk factor and to link ABCG8 and ABO variants to cardiovascular disease (CVD). BACKGROUND Plant sterol-enriched functional foods are widely used for cholesterol lowering. Their regular intake yields a 2-fold increase in circulating plant sterol levels that equally represent markers of cholesterol absorption. Variants in ABCG8 and ABO have been associated with circulating plant sterol levels and CVD, thereby suggesting atherogenic effects of plant sterols or of cholesterol uptake. METHODS The cholestanol-to-cholesterol ratio (CR) was used as an estimate of cholesterol absorption because it is independent of plant sterols. First, we investigated the associations of 6 single nucleotide polymorphisms in ABCG8 and ABO with CR in the LURIC (LUdwisghafen RIsk and Cardiovascular health study) and the YFS (Young Finns Study) cohorts. Second, we conducted a systematic review and meta-analysis to investigate whether CR might be related to CVD. RESULTS In LURIC, the minor alleles of rs4245791 and rs4299376 and the major alleles of rs41360247, rs6576629, and rs4953023 of the ABCG8 gene and the minor allele of rs657152 of the ABO gene were significantly associated with higher CR. Consistent results were obtained for rs4245791, rs4299376, rs6576629, and rs4953023 in YFS. The meta-analysis, including 6 studies and 4,362 individuals, found that CR was significantly increased in individuals with CVD. CONCLUSIONS High cholesterol absorption is associated with risk alleles in ABCG8 and ABO and with CVD. Harm caused by elevated cholesterol absorption rather than by plant sterols may therefore mediate the relationships of ABCG8 and ABO variants with CVD.

IN.PACT Amphirion paclitaxel eluting balloon versus standard percutaneous transluminal angioplasty for infrapopliteal revascularization of critical limb ischemia: rationale and protocol for an ongoing randomized controlled trial

BACKGROUND The effectiveness and durability of endovascular revascularization therapies for chronic critical limb ischemia (CLI) are challenged by the extensive burden of infrapopliteal arterial disease and lesion-related characteristics (e.g., severe calcification, chronic total occlusions), which frequently result in poor clinical outcomes. While infrapopliteal vessel patency directly affects pain relief and wound healing, sustained patency and extravascular care both contribute to the ultimate "patient-centric" outcomes of functional limb preservation, mobility and quality of life (QoL). METHODS/DESIGN IN.PACT DEEP is a 2:1 randomized controlled trial designed to assess the efficacy and safety of infrapopliteal arterial revascularization between the IN.PACT Amphirion™ paclitaxel drug-eluting balloon (IA-DEB) and standard balloon angioplasty (PTA) in patients with Rutherford Class 4-5-6 CLI. DISCUSSION This multicenter trial has enrolled 358 patients at 13 European centers with independent angiographic core lab adjudication of the primary efficacy endpoint of target lesion late luminal loss (LLL) and clinically driven target lesion revascularization (TLR) in major amputation-free surviving patients through 12-months. An independent wound core lab will evaluate all ischemic wounds to assess the extent of healing and time to healing at 1, 6, and 12 months. A QoL questionnaire including a pain scale will assess changes from baseline scores through 12 months. A Clinical Events Committee and Data Safety Monitoring Board will adjudicate the composite primary safety endpoints of all-cause death, major amputation, and clinically driven TLR at 6 months and other trial endpoints and supervise patient safety throughout the study. All patients will be followed for 5 years. A literature review is presented of the current status of endovascular treatment of CLI with drug-eluting balloon and standard PTA. The rationale and design of the IN.PACT DEEP Trial are discussed. IN.PACT DEEP is a milestone, prospective, randomized, robust, independent core lab-adjudicated CLI trial that will evaluate the role of a new infrapopliteal revascularization technology, the IA-DEB, compared to PTA. It will assess the overall impact on infrapopliteal artery patency, limb salvage, wound healing, pain control, QoL, and patient mobility. The 1-year results of the adjudicated co-primary and secondary endpoints will be available in 2014. TRIAL REGISTRATION NCT00941733

Animal Guts as Ideal Chemical Reactors: Maximizing Absorption Rates

I solved equations that describe coupled hydrolysis in and absorption from a continuously stirred tank reactor (CSTR), a plug flow reactor (PFR), and a batch reactor (BR) for the rate of ingestion and/or the throughput time that maximizes the rate of absorption (=gross rate of gain from digestion). Predictions are that foods requiring a single hydrolytic step (e.g., disaccharides) yield ingestion rates that vary inversely with the concentration of food substrate ingested, whereas foods that require multiple hydrolytic and absorptive reactions proceeding in parallel (e.g., proteins) yield maximal ingestion rates at intermediate substrate concentrations. Counterintuitively, then, animals acting to maximize their absorption rates should show compensatory ingestion (more rapid feeding on food of lower concentration), except for the lower range of diet quality fur complex diets and except for animals that show purely linear (passive) uptake. At their respective maxima in absorption rates, the PFR and BR yield only modestly higher rates of gain than the CSTR but do so at substantially lower rates of ingestion. All three ideal reactors show milder than linear reduction in rate of absorption when throughput or holding time in the gut is increased (e.g., by scarcity or predation hazard); higher efficiency of hydrolysis and extraction offset lower intake. Hence adding feeding costs and hazards of predation is likely to slow ingestion rates and raise absorption efficiencies substantially over the cost-free optima found here.

The MI SYNTAX score for risk stratification in patients undergoing primary percutaneous coronary intervention for treatment of acute myocardial infarction: A substudy of the COMFORTABLE AMI trial.

BACKGROUND To investigate the performance of the MI Sxscore in a multicentre randomised trial of patients undergoing primary percutaneous coronary intervention (PPCI). METHODS AND RESULTS The MI Sxscore was prospectively determined among 1132 STEMI patients enrolled into the COMFORTABLE AMI trial, which randomised patients to treatment with bare-metal (BMS) or biolimus-eluting (BES) stents. Patient- (death, myocardial infarction, any revascularisation) and device-oriented (cardiac death, target-vessel MI, target lesion revascularisation) major adverse cardiac events (MACEs) were compared across MI Sxscore tertiles and according to stent type. The median MI SXscore was 14 (IQR: 9-21). Patients were divided into tertiles of Sxscorelow (≤10), Sxscoreintermediate (11-18) and Sxscorehigh (≥19). At 1year, patient-oriented MACE occurred in 15% of the Sxscorehigh, 9% of the Sxscoreintermediate and 5% of the Sxscorelow tertiles (p<0.001), whereas device-oriented MACE occurred in 8% of the Sxscorehigh, 6% of the Sxscoreintermediate and 4% of the Sxscorelow tertiles (p=0.03). Addition of the MI Sxscore to the TIMI risk score improved prediction of patient- (c-statistic value increase from 0.63 to 0.69) and device-oriented MACEs (c-statistic value increase from 0.65 to 0.70). Differences in the risk for device-oriented MACE between BMS and BES were evident among Sxscorehigh (13% vs. 4% HR 0.33 (0.15-0.74), p=0.007 rather than those in Sxscorelow: 4% vs. 3% HR 0.68 (0.24-1.97), p=0.48) tertiles. CONCLUSIONS The MI Sxscore allows risk stratification of patient- and device-oriented MACEs among patients undergoing PPCI. The addition of the MI Sxscore to the TIMI risk score is of incremental prognostic value among patients undergoing PPCI for treatment of STEMI.

Randomized comparison of biodegradable polymer sirolimus-eluting stents versus durable polymer everolimus-eluting stents for percutaneous coronary revascularization: Rationale and design of the BIOSCIENCE trial

Background Biodegradable polymers for release of antiproliferative drugs from metallic drug-eluting stents (DES) aim to improve long-term vascular healing and efficacy. We designed a large scale clinical trial to compare a novel thin strut, cobalt chromium DES with silicon carbide coating releasing sirolimus from a biodegradable polymer (Orsiro, O-SES) with the durable polymer-based Xience Prime everolimus-eluting stent (X-EES) in an all-comers patient population. Design The multicenter BIOSCIENCE trial (NCT01443104) randomly assigned 2,119 patients to treatment with biodegradable polymer SES or durable polymer EES at 9 sites in Switzerland. Patients with chronic stable coronary artery disease or acute coronary syndromes, including non-ST-elevation and ST-elevation myocardial infarction, were eligible for the trial if they had at least one lesion with a diameter stenosis >50% appropriate for coronary stent implantation. The primary endpoint target lesion failure (TLF) is a composite of cardiac death, target-vessel myocardial infarction, and clinically-driven target lesion revascularization within 12 months. Assuming a TLF rate of 8% at 12 months in both treatment arms and accepting 3.5% as a margin for non-inferiority, inclusion of 2,060 patients would provide 80% power to detect non-inferiority of the biodegradable polymer SES compared with the durable polymer EES at a one-sided type I error of 0.05. Clinical follow-up will be continued through five years. Conclusion The BIOSCIENCE trial will determine whether the biodegradable polymer SES is non-inferior to the durable polymer EES with respect to TLF.

Predictors of adverse events among patients undergoing primary percutaneous coronary intervention: insights from a pooled analysis of the COMFORTABLE AMI and EXAMINATION trials

Aims: The aim of this study was to identify predictors of adverse events among patients with ST-elevation myocardial infarction (STEMI) undergoing contemporary primary percutaneous coronary intervention (PCI). Methods and results: Individual data of 2,655 patients from two primary PCI trials (EXAMINATION, N=1,504; COMFORTABLE AMI, N=1,161) with identical endpoint definitions and event adjudication were pooled. Predictors of all-cause death or any reinfarction and definite stent thrombosis (ST) and target lesion revascularisation (TLR) outcomes at one year were identified by multivariable Cox regression analysis. Killip class III or IV was the strongest predictor of all-cause death or any reinfarction (OR 5.11, 95% CI: 2.48-10.52), definite ST (OR 7.74, 95% CI: 2.87-20.93), and TLR (OR 2.88, 95% CI: 1.17-7.06). Impaired left ventricular ejection fraction (OR 4.77, 95% CI: 2.10-10.82), final TIMI flow 0-2 (OR 1.93, 95% CI: 1.05-3.54), arterial hypertension (OR 1.69, 95% CI: 1.11-2.59), age (OR 1.68, 95% CI: 1.41-2.01), and peak CK (OR 1.25, 95% CI: 1.02-1.54) were independent predictors of all-cause death or any reinfarction. Allocation to treatment with DES was an independent predictor of a lower risk of definite ST (OR 0.35, 95% CI: 0.16-0.74) and any TLR (OR 0.34, 95% CI: 0.21-0.54). Conclusions: Killip class remains the strongest predictor of all-cause death or any reinfarction among STEMI patients undergoing primary PCI. DES use independently predicts a lower risk of TLR and definite ST compared with BMS. The COMFORTABLE AMI trial is registered at: http://www.clinicaltrials.gov/ct2/show/NCT00962416. The EXAMINATION trial is registered at: http://www.clinicaltrials.gov/ct2/show/NCT00828087.

New online method for water isotope analysis of speleothem fluid inclusions using laser absorption spectroscopy (WS-CRDS)

A new online method to analyse water isotopes of speleothem fluid inclusions using a wavelength scanned cavity ring down spectroscopy (WS-CRDS) instrument is presented. This novel technique allows us simultaneously to measure hydrogen and oxygen isotopes for a released aliquot of water. To do so, we designed a new simple line that allows the online water extraction and isotope analysis of speleothem samples. The specificity of the method lies in the fact that fluid inclusions release is made on a standard water background, which mainly improves the δ D robustness. To saturate the line, a peristaltic pump continuously injects standard water into the line that is permanently heated to 140 °C and flushed with dry nitrogen gas. This permits instantaneous and complete vaporisation of the standard water, resulting in an artificial water background with well-known δ D and δ18O values. The speleothem sample is placed in a copper tube, attached to the line, and after system stabilisation it is crushed using a simple hydraulic device to liberate speleothem fluid inclusions water. The released water is carried by the nitrogen/standard water gas stream directly to a Picarro L1102-i for isotope determination. To test the accuracy and reproducibility of the line and to measure standard water during speleothem measurements, a syringe injection unit was added to the line. Peak evaluation is done similarly as in gas chromatography to obtain &delta D; and δ18O isotopic compositions of measured water aliquots. Precision is better than 1.5 ‰ for δ D and 0.4 ‰ for δ18O for water measurements for an extended range (−210 to 0 ‰ for δ D and −27 to 0 ‰ for δ18O) primarily dependent on the amount of water released from speleothem fluid inclusions and secondarily on the isotopic composition of the sample. The results show that WS-CRDS technology is suitable for speleothem fluid inclusion measurements and gives results that are comparable to the isotope ratio mass spectrometry (IRMS) technique.