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This study investigates the potential of a statistical-based, adaptive approach to unwrapping sequences of differential synthetic aperture radar (SAR) interferograms that cover a large swath of the terrain. The proposed method adopts a multiscale decomposition strategy to identify efficiently and then process sets of coherent points at different spatial scales. The coherent point selection process is performed considering the statistical properties of the stack of wrapped multilooked SAR interferograms generated at various scales. Overall, the adopted procedure allows automatically recognizing the areas in large swath interferograms where significant and reliable phase changes occur while moving from neighboring spatial scales. Over these regions, multiscale phase unwrapping (PhU) operations are performed efficiently, with a computational improvement and without losing significant information. To this aim, the implementation of a conditioned space-time PhU scheme that operates sequentially at different spatial grids is detailed. Then, the unwrapped interferograms are inverted to generate ground displacement time series through advanced multitemporal interferometric SAR (MT-InSAR) approaches, recovering information at different scales (from local to regional/continental). Experimental results have been obtained by applying the developed scheme to large-swath SAR datasets collected at the C band by Sentinel-1 sensors. The results demonstrate the feasibility and soundness of the developed multiscale PhU method.

Numerical simulations of the cardiovascular system are growing in popularity due to the increasing availability of computational power, and their proven contribution to the understanding of pathodynamics and validation of medical devices with in-silico trials as a potential future breakthrough. Such simulations are performed on volumetric meshes reconstructed from patient-specific imaging data. These meshes are most often unstructured, and result in a brutally large amount of elements, significantly increasing the computational complexity of the simulations, whilst potentially adversely affecting their accuracy. To reduce such complexity, we introduce a new approach for fully automatic generation of higher-order, structured hexahedral meshes of tubular structures, with a focus on healthy blood vessels. The structures are modeled as skeleton-based convolution surfaces. From the same skeleton, the topology is captured by a block-structure, and the geometry by a higher-order surface mesh. Grading may be induced to obtain tailored refinement, thus resolving, e.g., boundary layers. The volumetric meshing is then performed via transfinite mappings. The resulting meshes are of arbitrary order, their elements are of good quality, while the spatial resolution may be as coarse as needed, greatly reducing computing time. Their suitability for practical applications is showcased by a simulation of physiological blood flow modelled by a generalised Newtonian fluid in the human aorta.

Background In the United States, healthcare organizations utilize helicopter emergency medical services (HEMS), which are well-established and integral to trauma and emergency medical transport. HEMS expedites critical resources to trauma patients at the initial scene of the accident, which typically falls outside of the effective service area of ground transportation.Methods This is a single-center study of trauma registry data, inclusive years July 1, 2016, to September 26, 2021. The inclusion criteria were all adult ICU patients (≥18 years) traveling by air. An initial bivariate analysis was used to describe differences in HEMS vs rendezvous (ground + HEMS) mode of arrival. A multivariate linear regression was calculated to predict elapsed transport times on predictor variables to determine the clinical impact of prolonged transport times.Results There were 242 patients identified in the analysis, with 87 (36%) traveling by HEMS and 155 (64%) traveling by rendezvous. A significant regression equation was found (F(29,198) = 2.39, P< .01), with an R2 of .26. As the transport time increased by 10.67 minutes, the shock index ratio (SIR) increased by one unit (P= .04). Conversely, for each unit increase in Glasgow Coma Scores (GCS), flight time decreased by 1.03 minutes (P< .01). Rendezvous transport times were on average eight minutes longer than HEMS alone (P< .01).Conclusions Those with prolonged travel times were likely to travel by rendezvous with presentation of lower GCS and higher SIR upon arrival, despite equivocal injury patterns and severity. This research highlights the need for a helicopter auto-launch program to expedite helicopter travel times in distant locations to the only Level I trauma center in the region.

The current literature demonstrates an association between both size and presence of traumatic brain injury (TBI) and its effects on mortality, however it does not readily address the morbidity and associated functional outcomes of those who survive. We hypothesize that the likelihood of discharge to home decreases with advancement of age in the presence of TBI. This is a single-center study of Trauma Registry data, inclusive years July 1, 2016 to October 31, 2021. The inclusion criteria was based upon age (≥40 years), and ICD10 diagnosis of a TBI. Disposition to home without services was the dependent variable. 2031 patients were included in the analysis. We hypothesized correctly that the likelihood of discharge to home decreases (by 6%) with advancement of age (per year) in the presence of intracranial hemorrhage.

A recommended emergency medical services ambulance response time to a medical emergency is within eight minutes for at least 90% of calls. This study aimed to evaluate scene times for rural education and outreach to improve the quality of trauma care. This is a single-center study of Trauma Registry data from July 1, 2016 to February 28, 2022. The inclusion criteria were based upon age (≥18 years). A logistic regression was performed to identify predictor variables on the likelihood that an adult trauma patient will experience scene times greater than eight minutes. 19 321 patients were included in the analysis; 7233 (37%) experienced an elapsed scene time within eight minutes. This research identified an opportunity to improve rural trauma team response time, which is only reaching 37% of the patient population within eight minutes. Prehospital cardiac arrest and unique pre-existing comorbidities may play a role in extended response times by EMS.

Background The process of interfacility transfer may cause a delay in the necessary medical treatment, which could lead to poor outcomes and increased mortality rates. The ACS-COT considers an acceptable under triage rate of <5%. The aim of this research was to identify the likelihood of under triage among transferred-in traumatic brain injury (TBI) patients.Methods This is a single-center study of Trauma Registry data, from July 1, 2016, to October 31, 2021. The inclusion criteria were based upon age (≥40 years), ICD10 diagnosis of TBI, and interfacility transfer. Under triage using the Cribari matrix method was the dependent variable. A logistic regression was performed to identify additional predictor variables on the likelihood that an adult TBI trauma patient experienced under triage.Results 878 patients were included in the analysis; 168 (19%) experienced an under triage. The logistic regression model was statistically significant (N = 837, P< .01). In addition, several significant increases in odds for under triage were identified, which included increasing injury severity score (ISS; OR 1.40, P< .01), increasing AIS head region (OR 6.19, P< .01), and personality disorders (OR 3.61, P= .02). In addition, a reduction in odds in TBI adult trauma under triage is the comorbidity of anticoagulant therapy (OR .25, P< .01).Conclusions The likelihood of under triage in the adult TBI trauma population is associated with increasing AIS head injuries and increasing ISS and among those with mental health comorbidities. This evidence and additional protective factors, such as patients on anticoagulant therapy, may aid in education and outreach efforts to reduce under triage among the regional referring centers.

The leading cause of preventable traumatic death is uncontrolled bleeding. This study aimed to better identify those most likely to experience in-hospital mortality with increasing injury severity scoring (ISS). This is a single-center study of Trauma Registry data, from July 3, 2016, to February 24, 2022. The inclusion criteria were based upon age (≥18 years) and in-hospital mortality. 546 patients (mean age 58) were included in the analysis. There were several significant associations with increasing ISS among those who experienced in-hospital mortality, which included a rising shock index ratio, activation of the massive transfusion protocol, and, most notably, motorcycle trauma. This research reiterates the importance of the “Stop the Bleed” campaign as vital for training laypersons in the life-saving technique for hemorrhage control.

The leading cause of preventable traumatic death is uncontrolled bleeding. This study aimed to better identify those most likely to experience in-hospital mortality with increasing injury severity scoring (ISS). This is a single-center study of Trauma Registry data, from July 3, 2016, to February 24, 2022. The inclusion criteria were based upon age (≥18 years) and in-hospital mortality. 546 patients (mean age 58) were included in the analysis. There were several significant associations with increasing ISS among those who experienced in-hospital mortality, which included a rising shock index ratio, activation of the massive transfusion protocol, and, most notably, motorcycle trauma. This research reiterates the importance of the “Stop the Bleed” campaign as vital for training laypersons in the life-saving technique for hemorrhage control.

The current literature demonstrates an association between both size and presence of TBI and its effects on mortality; however, it does not readily address the morbidity and associated functional outcomes of those who survive. We hypothesize that the likelihood of discharge to home decreases with advancement of age in the presence of TBI. This is a single-center study of trauma registry data, inclusive years July 1, 2016, to October 31, 2021. The inclusion criteria was based upon age (≥40 years), and ICD10 diagnosis of a TBI. Disposition to home without services was the dependent variable. 2031 patients were included in the analysis. We hypothesized correctly that the likelihood of discharge to home decreases (by 6%) with advancement of age (per year) in the presence of intracranial hemorrhage.

This study aimed to evaluate non-survivors who were admitted to a level I trauma center but later died, in terms of predicting who would expire early vs late. This is a single-center study of Trauma Registry data, from July 3, 2016, to February 24, 2022. The inclusion criteria were based upon age (≥18 years) and in-hospital mortality. 546 patients (mean age 58) were included in the analysis. Trauma patients who may experience an earlier death were those with increasing injury severity scores, activation of massive transfusion protocol, comorbid advanced directive limiting care, COPD, personality disorder, and ED death location. Patients were more likely to experience later in-hospital mortality, including those with increasing ICU stays, and comorbid dementia.

This research aims to evaluate the specific effects of end-stage renal disease on acutely injured trauma patients. This is a single-center study of Trauma Registry data, inclusive years July 1, 2016 to February 28, 2021. Patients were grouped by pre-existing comorbidity of chronic kidney disease (CKD) and those without. Overall, 7261 elderly trauma patients were included in the analysis; stratified groups identified 197 with CKD (3%) and 7064 without (97%). The Injury Severity Scores (ISSs) between the two groups were not significantly different. Elderly trauma patients with CKD typically stayed in the ICU and hospital longer with discharge to hospice, rehab, experienced an in-hospital mortality, and most likely experienced an in-hospital complication. For CKD and non-CKD cohorts, ISSs were similar. However, outcomes for the CKD cohort in the trauma setting were significantly worse, particularly in elderly patients with fall trauma and lower extremity fractures.

This study aims to assess chemical VTE prophylactic type and timing and associated outcomes within the elderly trauma population. This is a single center study of Trauma Registry data, inclusive years July 1, 2016, to February 28, 2021. The patients were grouped based upon discharge disposition. 7261 elderly trauma patients were included in the analysis. Late administration of VTE prophylaxis was associated with a discharge disposition to hospice. Administration of unfractionated heparin was most associated with in-hospital mortality. Xa inhibitors had the least impact on morbidity and mortality, with most likely associations in discharge to rehab or a skilled nursing facility. LMWH associated with a discharge to a rehab facility. The timing of administration and type of VTE prophylaxis may significantly affect the morbidity and mortality outcomes in elderly trauma.

Isolated hip fractures (IHFs) contribute to functional decline in the elderly. Our purpose was to evaluate IHF at two level 1 trauma centers and the effect of comorbidities on length of stay (LOS), ICU admission, disposition, and mortality. A retrospective study from July 2016 through December 2020 including patients ≥65 with IHFs identified 785 patients. Prior dependent functional status yielded a longer LOS (>6 days vs <6 days, P= .01). Comorbidities were not associated with increased LOS or ICU admission. ICU admission rate was 12.75%. Patients with advanced directive had increased ICU admission (8% vs 3%). The mortality rate was 2%. Increased mortality was seen with advanced directives (17% vs 2%, P< .05) and cirrhosis/substance abuse (12% vs 2%, P< .05). Disposition included home (20%), rehabilitation (43%), and SNF (31%). Comorbidities did not affect ICU admission, LOS, or disposition; however, cirrhosis/substance abuse demonstrated increased mortality.

This study aims at identifying the under-triage patients to improve the quality of care among those transferred into a level I trauma system. This is a single-center study of Trauma Registry data, inclusive years, from July 1, 2016 to January 31, 2021. Patients were grouped based upon under-triage, over-triage, and OK triage. The under-triage group was more likely to be older, partially activated, blunt, fall trauma patients with a higher GCS, higher ISS, and significant injuries found to the head/neck who experienced a longer length of stay at the referring facility and higher morbidity outcomes with diagnosed comorbidities of dementia and hypertension. There are distinct differences in under and over-triage groups within this trauma system, which gives insight into future education and outreach among interfacility transfers.

Leadless pacemaker (LP) therapy has been proved effective in cases where traditional transvenous right pacing (TRP) failed. TRP through a bioprosthetic tricuspid valve (BTV) has always been considered an unpreferable solution because of possible deleterious effect of permanent pacing leads on BTV function and specifically on tricuspid regurgitation (TR). Very limited data exist about the feasibility and safety of LP implantation in this setting. We describe two cases of LP implantation through BTV in patients with failure of epicardial pacemaker implanted after cardiac surgery. The focus is on technical description of the procedure and on electrical and echocardiographic evaluation at implantation and at the follow‐up. In both cases, skilled and careful handling of the delivery system as well as proper use of X‐ray oblique views was determinant for atraumatic successful valve crossing. Likewise, an accurate selection of the deployment site inside the right ventricle, far enough from the valve to avoid valvular dysfunction, was important for successful implantation. Electrical parameters of LP were satisfying at implantation and at the follow‐up. The echocardiogram after implantation and at the follow‐up showed no mechanical interference of LP with prosthetic valve, no significant TR, and absence of significant changes in the biventricular function. Our data seem to support feasibility and safety of this type of procedure in skilled hands, allowing efficacious pacing without valvular dysfunction or right ventricular (RV) physiology impairment. Leadless pacemaker (LP) therapy has been proved effective in cases where traditional transvenous right pacing (TRP) failed. TRP through a bioprosthetic tricuspid valve (BTV) has always been considered an unpreferable solution because of possible deleterious effect of permanent pacing leads on BTV function and specifically on tricuspid regurgitation (TR). Very limited data exist about the feasibility and safety of LP implantation in this setting. We describe two cases of LP implantation through BTV in patients with failure of epicardial pacemaker implanted after cardiac surgery. The focus is on technical description of the procedure and on electrical and echocardiographic evaluation at implantation and at the follow‐up. In both cases, skilled and careful handling of the delivery system as well as proper use of X‐ray oblique views was determinant for atraumatic successful valve crossing. Likewise, an accurate selection of the deployment site inside the right ventricle, far enough from the valve to avoid valvular dysfunction, was important for successful implantation. Electrical parameters of LP were satisfying at implantation and at the follow‐up. The echocardiogram after implantation and at the follow‐up showed no mechanical interference of LP with prosthetic valve, no significant TR, and absence of significant changes in the biventricular function. Our data seem to support the feasibility and safety of this type of procedure in skilled hands, allowing efficacious pacing without valvular dysfunction or RV physiology impairment.

Acute small bowel obstruction (SBO) is a common cause of emergency department visits in the United States, and it accounts for approximately 20% of emergency surgical operations.1Its etiology is divided into intrinsic luminal obstruction or extrinsic compression of the bowel.2Among the causes of SBO, by far the most common is intraperitoneal adhesions due to previous abdominal surgeries, which comprises about 60-70% of the cases.2The abdominal cavity is subdivided into the peritoneal cavity and the retroperitoneal cavity; the division is marked by a thin covering of parietal peritoneum that encases all the intraperitoneal structures. Here, we present a rare case of an acute small bowel obstruction secondary to exposure of the retroperitoneal external iliac artery from a surgical procedure 20 years prior to presentation.

Anticoagulated older adults suffering ground-level falls are a specialty trauma population at risk for intracranial hemorrhage (ICH). Delays in diagnosis or initiation of anticoagulation reversal can lead to increased morbidity/mortality. A novel “Headstrike” protocol was implemented to improve the treatment efficacy and disposition of these patients. The study objective was to determine effectiveness of the “Headstrike” protocol in providing these patients with timely treatment and disposition, while maintaining positive outcomes. A trauma performance improvement database was queried for all “Headstrike” activations for a 12-month period after implementation. Demographics, patient care, and health data were collected. Descriptive statistics were used for cohort analysis. Five hundred fifteen patients were activated as a “Headstrike” during the study period. Thirty eight patients were diagnosed with ICH (7.4%), 35 of whom were identified on initial imaging. Anticoagulation reversal was ordered for 84.6 per cent of these patients. Of the patients with negative initial CT, only three patients (0.8%) were found to have a delayed ICH on routine follow-up imaging. No anticoagulant/antiplatelet agent was associated with a significantly higher risk of ICH. Implementation of the “Headstrike” protocol resulted in trauma service line resources being used more efficiently, while ensuring high-quality, expeditious care to this population.

During the 2012 Emilia‐Romagna (Italy) seismic sequence, several time‐dependent phenomena occurred, such as changes in the groundwater regime and chemistry, liquefaction, and postseismic ground displacements. Because time‐dependent phenomena require time‐dependent physical mechanisms, we interpreted such events as the result of the poroelastic response of the crust after the main shock. In our study, we performed a two‐dimensional poroelastic numerical analysis calibrated with Cosmo‐SkyMed interferometric data and measured piezometric levels in water wells. The simulation results are consistent with the observed postseismic ground displacement and water level changes. The simulations show that crustal volumetric changes induced by poroelastic relaxation and the afterslip along the main shock fault are both required to reproduce the amplitude (approximately 4 cm) and temporal evolution of the observed postseismic uplift. Poroelastic relaxation also affects the aftershock distribution. In fact, the aftershocks are correlated with the postseismic Coulomb stress evolution. In particular, a considerably higher fraction of aftershocks occurs when the evolving poroelastic Coulomb stress is positive. These findings highlight the need to perform calculations that adequately consider the time‐dependent poroelastic effect when modeling postseismic scenarios, especially for forecasting the temporal and spatial evolution of stresses after a large earthquake. Failing to do so results in an overestimation of the afterslip and an inaccurate definition of stress and strain in the postseismic phase. The postseismic phenomena that occurred after the 2012 Mw5.9 northern Italy earthquake depended on the poroelastic response of the crustPoroelastic relaxation is equally important as the afterslip in terms of the aftershock distributionDInSAR ground deformation data and in‐well water level changes were used to successfully calibrate the poroelastic numerical model

Historically, tube thoracostomy, image-guided drainage, or an open thoracotomy has been indicated as the standard procedure for the management of patients with retained infected pleural collections (RIPC). These infections can be a debilitating and potentially lethal complication in already critically ill trauma patients. The purpose of this review was to evaluate the usefulness of an open thoracic window (OTW) as definitive therapy for the management of RIPC refractory to conventional therapies. The medical records of patients who underwent an OTW for RIPC were reviewed for the following: demographic data, primary diagnosis, clinical findings that explained the failure of the conventional management, bacteriology of the retained collection, and final outcome. Over a 3-year period, eight critically ill trauma patients who had sustained multiple system trauma and developed a RIPC were identified (six males and two females; average age, 47 years). Of the eight patients identified, six collections were in the right and two in the left pleural cavity. Staphylococcus aureusand Acinetobacterwere the two most common bacterial isolates from these collections. All patients had undergone multiple and unsuccessful drainage attempts by thoracostomy tubes. Additionally, two of the patients also underwent image-guided drainage procedures, which proved to be unsuccessful. After creation of the OTW, all patients had complete resolution of the RIPC, and all were discharged alive from the hospital. During outpatient follow up, the OTW was found to have completely healed and required no further surgical intervention. The creation of long-term pleural drainage, with an OTW, facilitates and expedites the resolution of persistent infected pleural collections by providing more efficient surgical drainage and mechanical debridement. Our experience also shows this uncommon operation to be an effective alternative when conventional measures have failed.

PURPOSE: We present a case-control study of seven polymorphisms of six genes involved in homocysteine/folate pathway as risk factors for Down syndrome. Gene-gene/allele-allele interactions, haplotype analysis and the association with age at conception were also evaluated.METHODS: We investigated 94 Down syndrome-mothers and 264 control-women from Campania, Italy.RESULTS: Increased risk of Down syndrome was associated with the methylenetetrahydrofolate reductase (MTHFR) 1298C allele (OR 1.46; 95% CI 1.02–2.10), the MTHFR 1298CC genotype (OR 2.29; 95% CI 1.06–4.96), the reduced-folate-carrier1 (RFC1) 80G allele (1.48; 95% CI 1.05–2.10) and the RFC1 80 GG genotype (OR 2.05; 95% CI 1.03–4.07). Significant associations were found between maternal age at conception =34 years and either the MTHFR 1298C or the RFC 180G alleles. Positive interactions were found for the following genotype-pairs: MTHFR 677TT and 1298CC/CA, 1298CC/CA and RFC1 80 GG/GA, RFC1 80 GG and methylenetetrahydrofolate-dehydrogenase 1958 AA. The 677–1298 T-C haplotype at the MTHFR locus was also a risk factor for Down syndrome (P = 0.0022). The methionine-synthase-reductase A66G, the methionine-synthase A2756G and the cystathionine-beta-synthase 844ins68 polymorphisms were not associated with increased risk of Down syndrome.CONCLUSION: These results point to a role of maternal polymorphisms of homocysteine/folate pathway as risk factors for Down syndrome.

Using a bioinformatic approach, we have identified a new transcript, SLC7A8, mapping to 14q11.2, within the lysinuric protein intolerance (LPI) critical region. This gene is highly expressed in skeletal muscle, intestine, kidney, and placenta and encodes a predicted protein of 535 amino acids, homologous to the amino acid permease CD98 light chain and cationic amino acid transporters. RNA in situhybridization data on mouse embryos confirm the expression in kidney and intestine and, interestingly, reveal that SLC7A8 is also highly expressed in eye, in retinal pigmented epithelium, and in tooth buds at day 16.5 of gestation. Mutational analysis excluded any direct involvement of the SLC7A8 gene product in LPI disease. The homology data and the expression pattern are in agreement with the hypothesis that SLC7A8 represents a novel light chain interacting with the 4F2 heavy chain in the multimeric complex mediating neutral and/or cationic amino acid transport and cystine/glutamate exchange.

We develop finite element models of the coseismic displacement field accounting for the 3D elastic structures surrounding the epicentral area of the 2019 Ridgecrest earthquake sequence containing two major events of Mw7.1 and Mw6.4. The coseismic slip distribution is inferred from the surface displacement field recorded by interferometric synthetic aperture radar. The rupture dip geometry is further optimized using a novel nonlinear‐crossover‐linear inversion approach. It is found that accounting for elastic heterogeneity and fault along‐strike curvilinearity improves the fit to the observed displacement field and yields a more accurate estimate of geodetic moment and Coulomb stress changes. We observe spatial correlations among the locations of aftershocks and patches of high slip, and rock anomalous elastic properties, suggesting that the shallow crust's elastic structures possibly controlled the Ridgecrest earthquake sequence. Most of the coseismic slip with a peak slip of 7.4 m at 3.6 km depth occurred above a zone of reduced S‐wave velocity and significant post‐Mw7.1 afterslip. This implies that viscous materials or fluid presence might have contributed to the low rupture velocity of the mainshock. Moreover, the zone of high slip on the northwest‐trending fault segment is laterally bounded by two aftershock clusters, whose location is characterized by intermediate rock rigidity. Notably, some minor orthogonal faults consistently end above a subsurface rigid body. Overall, these observations of structural controls improve our understandings of the seismogenesis within incipient fault systems. On July 4 and 5, 2019, a magnitude 7.1 and 6.4 earthquake occurred near the town, Ridgecrest, California. The permanent surface movements induced by these events were captured by satellite images. Here, we develop realistic numerical models and innovational optimization algorithms to investigate the displacement fields and image the distribution of the earthquake slip. These events were hosted by a pair of orthogonal faults and their resolved orientations are similar to the nearby known fault structures. We discover that the fault slip and aftershock locations could be related to the local rock materials, suggesting that the variable elastic properties of the shallow crust might have influenced the development of the Ridgecrest earthquake sequence. As also supported by other seismic and geophysical datasets, most of the coseismic slip appeared over a zone of elastic weakness where could be relevant to subsurface viscous or fluid bodies, meanwhile, aftershocks tended to cluster within a shallow rigid body. Overall, the findings of this study provide insights into potential structural controls over the seismic occurrence and help improve our understandings of the seismogenesis within the western Mojave desert. Heterogeneous velocity structures in the epicentral area are simulated in elastic modelsPeak slip occurred above a zone of reduced S‐wave velocity and documented afterslipMost aftershocks are located outside slip asperities and within a shallow brittle zone Heterogeneous velocity structures in the epicentral area are simulated in elastic models Peak slip occurred above a zone of reduced S‐wave velocity and documented afterslip Most aftershocks are located outside slip asperities and within a shallow brittle zone

We evaluated the impact of increasing the interval between routine central venous catheter exchanges from every 3 days to every 4 days on the rate of catheter infections and catheter-related bacteremia. Computer records of catheter tip and blood culture results in burn patients were reviewed. The change to every 4 day catheter exchange occurred in November 2000 and data were collected until June 2001. One hundred and ninety-six guidewire exchanges were performed in the every 3 day (q3day) group, and 164 guidewire exchanges were performed in the every 4 day (q4day) group. The rate of catheter infections (>15 colony forming units) was 11% in the q3day group and 28% in the q4day group. Catheter-related blood stream infection occurred in 4% of patients in q3day group and 12% of patients in q4day group. A prospective review of this change in practice revealed that there was a significantly greater risk of infections in the q4day group. The increase in infected central venous catheter segments was associated with an increase in blood stream infections.