Chiari I malformations with syringomyelia: long-term results of neurosurgical decompression.

STUDY DESIGN: Retrospective case series. OBJECTIVES: The objective was to assess the long-term outcomes on scoliosis following Chiari-I (CM-I) decompression in patients with CM-I and syringomyelia (SM). A secondary objective was to identify risk factors of scoliosis progression. BACKGROUND: The association between CM-I with SM and scoliosis is recognized, but it remains unclear if CM-I decompression alters the long-term evolution of scoliosis in patients with associated syringomyelia. METHODS: A retrospective review of children with scoliosis, CM-I, and SM during 1997-2015 was performed. Congenital, syndromic, and neuromuscular scoliosis were excluded. Clinical and radiographic characteristics were recorded at presentation, pre-decompression, after 1-year, and latest follow-up. A scale to measure syringomyelia area on MRI was used to evaluate SM changes post-decompression. RESULTS: 65 children with CM-I, SM, and scoliosis and a mean age of 8.9 years (range 0.7-15.8) were identified. Mean follow-up was 6.9 years (range 2.0-20.4). Atypical curves were present in 28 (43%) children. Thirty-eight patients (58%) underwent decompression before 10 years. Syringomyelia size reduced a mean of 70% after decompression (p < 0.001). Scoliosis improved in 26 (40%), stabilized in 17 (26%), and progressed in 22 (34%) cases. Early spinal fusion was required in 7 (11%) patients after a mean of 0.5 ± 0.37 years and delayed fusion in 16 (25%) patients after 6.0 ± 3.24 years. The remaining 42 (65%) patients were followed for a median of 6.1 years (range 2.0-12.3) without spine instrumentation or fusion. Fusion patients experienced less improvement in curve magnitude 1-year post-decompression (p < 0.001) and had larger curves at presentation (43° vs. 34°; p = 0.004). CONCLUSIONS: Syringomyelia size decreased by 70% after CM-I decompression and scoliosis stabilized or improved in two-thirds of patients. Greater curve improvement within the first year post-decompression and smaller curves at presentation decreased the risk of spinal fusion. Neurosurgical decompression is recommended in children with CM-I, SM, and scoliosis with the potential to treat all three conditions. LEVEL OF EVIDENCE: Level IV.

Combined Reconstruction of the Medial Patellofemoral Ligament (MPFL) and Medial Quadriceps Tendon-Femoral Ligament (MQTFL) for Patellar Instability in Children and Adolescents: Surgical Technique and Outcomes.

OBJECTIVES: A variety of surgical options exist to treat the challenging problem of recurrent patellar instability in children and adolescents. The goal of the current study is to describe a novel combined reconstruction technique of both the medial patellofemoral ligament (MPFL) and the medial quadriceps tendon-femoral ligament (MQTFL) and report patient outcomes of a single-surgeon series. METHODS: All patients studied underwent simultaneous MPFL and MQTFL reconstruction for patellar instability using gracilis allograft. Demographic, clinical, and radiographic data were collected. Subjective outcomes were assessed for a minimum of 1 year postoperatively. RESULTS: Twenty-five patients (27 knees), including 15 female and 10 male individuals with an average age of 15.0±2.2 years (range, 10.3 to 18.9), were included. Prior ipsilateral patellofemoral surgery had been performed in 6 of 25 (24%) patients. Simultaneous hemiepiphysiodesis for valgus deformity at the time of combined reconstruction was performed in 5 of 25 (20%) patients. Preoperative imaging showed a mean tibial tubercle-trochlear groove of 17.2±3.8, Caton-Deschamps Index (CDI) of 1.13±0.16, and trochlear dysplasia Dejour A/B [22/26 (85%)] or Dejour C/D [4/26 (15%)]. A total of 18 patients (19 knees, 72%) returned outcomes questionnaires at a mean 2.0±0.5 years after surgery. Mean Kujala, Pedi-IKDC, and Lysholm scores were 85.9±13.9, 81.5±15.2, and 84.3±13.5, respectively. Later revision procedure (tibial tubercle osteotomy) for recurrent patellar instability was required in 2 of 25 patients (8%) patients, and another patient reported persistent instability not requiring revision. Return to sports was possible in 10 of 13 self-reported athletes (77%) at a mean of 5.8±3.9 months (range, 2 to 15). CONCLUSIONS: The present study describes a combined MPFL-MQTFL reconstruction technique with favorable short-term results. Although particularly useful in the skeletally immature patient where tibial tubercle osteotomy should be avoided and patellar fixation minimized, combined reconstruction may potentially be appropriate for older patients with patellofemoral instability as well. This technique more closely recreates the native anatomy of both the MPFL and MQTFL, may decrease the risk of patellar fracture, and can be useful in the revision setting. LEVEL OF EVIDENCE: Level IV.

Toxicity of Potassium Chloride Compared to Sodium Chloride for Zebra Mussel Decontamination.

The use of chemicals to decontaminate watercraft and/or equipment after exposure to zebra mussels Dreissena polymorpha is one method of decontamination that has been recommended by multiple government agencies in the United States. The ideal chemical to be used for decontamination would be inexpensive and easily obtained, would have no or limited effect on nontarget species, and would be relatively environmentally friendly. Two chemicals that have been tested are potassium chloride (KCl) and sodium chloride (NaCl). The toxicity of each chemical to both adult zebra mussels and veliger larvae was examined. Sodium chloride was less effective at causing mortality than KCl within the exposure periods tested. Adult mussels required a 4× longer exposure period to exhibit complete mortality when exposed to NaCl at 30,000 mg/L (24 h) compared to KCl (6 h). At 10,000 mg/L, NaCl took 8× longer (96 h) than KCl (12 h) to cause 100% mortality of adult mussels. Veligers that were exposed to KCl at 1,250 mg/L required a 12-h exposure to attain complete mortality, while those exposed to NaCl at 10,000 mg/L required an 18-h exposure to exhibit the same result. To determine whether KCl is more advantageous as a decontamination chemical, the cost and chemical availability must be researched.

Importance of accurate spectral simulations for the analysis of terahertz spectra: citric acid anhydrate and monohydrate.

The terahertz (THz) spectra of crystalline solids are typically uniquely sensitive to the molecular packing configurations, allowing for the detection of polymorphs and hydrates by THz spectroscopic techniques. It is possible, however, that coincident absorptions may be observed between related crystal forms, in which case careful assessment of the lattice vibrations of each system must be performed. Presented here is a THz spectroscopic investigation of citric acid in its anhydrous and monohydrate phases. Remarkably similar features were observed in the THz spectra of both systems, requiring the accurate calculation of the low-frequency vibrational modes by solid-state density functional theory to determine the origins of these spectral features. The results of the simulations demonstrate the necessity of reliable and rigorous methods for THz vibrational modes to ensure the proper evaluation of the THz spectra of molecular solids.

Will emergency health care providers respond to mass casualty incidents?

UNLABELLED: Emergency response plans often call on health care providers to respond to the workplace outside of their normal working pattern. HYPOTHESIS: Providers will report to work during a mass casualty emergency regardless of family duties, type of incident, or availability of treatment. METHODS: Survey of emergency personnel needed to respond to a mass casualty incident. Two scenarios were presented: one involving the release of a non-transmissible biological agent with proven treatment and the other the release of a transmissible biological agent with no treatment. At critical time points, participants were asked whether they would report to work. Additional questions considered the effect of commonly used treatment dissemination methods. RESULTS: A total of 186 surveys were issued and returned. (45 physicians, 29 nurses, 86 EMS personnel, and 20 support staff); 6 were incomplete and excluded. Initial commitment rates were 78%. The highest commitment rate identified was 84% and the lowest was 18%. Any treatment dissemination method excluding providers' family members led to decreases in commitment rate, as did agents identified to be transmissible. CONCLUSIONS: As an event develops, fewer health care providers will report to work and at no time will all providers report when asked. This conclusion may be generalizable to several types of incidents ranging from pandemic influenza to bioterrorism. Identification of the causative agent is a major decision point for providers to return to or stay away from work. Offering on-site treatment of providers' family increases commitment to work. These factors should be considered in emergency planning.

Will emergency health care providers respond to mass casualty incidents?

INTRODUCTION: Emergency response plans often call on health care providers to respond to the workplace outside of their normal working pattern. HYPOTHESIS: Providers will report to work during a mass casualty emergency regardless of family duties, type of incident, or availability of treatment. METHODS: Survey of emergency personnel needed to respond to a mass casualty incident. Two scenarios were presented: one involving the release of a nontransmissible biological agent with proven treatment and the other the release of a transmissible biological agent with no treatment. At critical time points, participants were asked whether they would report to work. Additional questions considered the effect of commonly used treatment dissemination methods. RESULTS: A total of 186 surveys were issued and returned. (45 physicians, 29 nurses, 86 EMS personnel, and 20 support staff); 6 were incomplete and excluded. Initial commitment rates were 78%. The highest commitment rate identified was 84% and the lowest was 18%. Any treatment dissemination method excluding providers' family members led to decreases in commitment rate, as did agents identified to be transmissible. CONCLUSIONS: As an event develops, fewer health care providers will report to work and at no time will all providers report when asked. This conclusion may be generalizable to several types of incidents ranging from pandemic influenza to bioterrorism. Identification of the causative agent is a major decision point for providers to return to or stay away from work. Offering on-site treatment of providers' family increases commitment to work. These factors should be considered in emergency planning.

Description and evaluation of a pilot physician-directed emergency medical services diversion control program.

OBJECTIVES: To describe the characteristics and feasibility of a physician-directed ambulance destination-control program to reduce emergency department (ED) overcrowding, as measured by hospital ambulance diversion hours. METHODS: This controlled trial took place in Rochester, New York and included a university hospital and a university-affiliated community hospital. During July 2003, emergency medical services (EMS) providers were asked to call an EMS destination-control physician for patients requesting transport to either hospital. The destination-control physician determined the optimal patient destination by using patient and system variables as well as EMS providers' and patients' input. Program process measures were evaluated to characterize the program. Administrative data were reviewed to compare system characteristics between the intervention program month and a control month. RESULTS: During the intervention month, 2,708 patients were transported to the participating hospitals. EMS providers contacted the destination-control physician for 1,866 (69%) patients. The original destination was changed for 253 (14%) patients. Reasons for redirecting patients included system needs, patient needs, physician affiliation, recent ED or hospital care, patient wishes, and primary care physician wishes. During the intervention month, EMS diversion decreased 190 (41%) hours at the university hospital and 62 (61%) hours at the community hospital, as compared with the control month. CONCLUSIONS: A voluntary, physician-directed destination-control program that directs EMS units to the ED most able to provide appropriate and timely care is feasible. Patients were redirected to maximize continuity of care and optimally use available emergency health care resources. This type of program may be effective in reducing overcrowding.

Validation of using EMS dispatch codes to identify low-acuity patients.

OBJECTIVE: To validate the predictive ability of previously derived emergency medical services (EMS) dispatch codes to identify patients with low-acuity illnesses. METHODS: This prospective descriptive study was conducted in Rochester, New York. An expert panel reviewed and modified a previously derived set of low-priority EMS dispatch codes. Patients assigned these 21 codes between July 2002 and June 2003 were included for further analysis. Dispatch data and level of EMS care were recorded for each dispatch code. The proportion of low-acuity patients (i.e., those who received only basic life support (BLS) care or those who were not transported using lights and sirens) was determined using previously established definitions. Codes were defined as associated with low-acuity patients if the lower bound of the 95% confidence interval (CI) exceeded 90%. Medical records for patients identified as high-acuity were reviewed to evaluate whether the advanced life support (ALS) level care that was provided had a clinical impact. RESULTS: Emergency medical services cared for 43,602 patients during the study, and 7,540 were dispatched as low-priority. We found that 7,197 (95%; 95% CI: 95-96%) of these patients met low-acuity criteria and that 11 of the evaluated codes were validated, with low-acuity care provided at least 90% of the time. Of the 343 patients identified as high-acuity, 62 (18%; 95% CI: 14-23%) were determined to have received interventions that had a clinical impact. CONCLUSIONS: This study prospectively validates 11 EMS dispatch codes as being associated with low-acuity patients. These codes could be used to triage EMS patients based on dispatch information.

An evaluation of paramedics' ability to screen older adults during emergency responses.

OBJECTIVES: This study evaluated the feasibility of using the emergency medical services (EMS) system as a public health provider by having paramedics screen older adults (age >or= 65 years) for influenza immunization status during emergency responses. It also determined the proportion of older-adult EMS patients who lacked an influenza vaccination. METHODS: A retrospective descriptive study was performed, with medical-record review for patients treated between January 2003 and April 2003. Patients were included if they were age 65 years and older, requested assistance via a 9-1-1 call, and were treated by one of 13 paramedics using a directed medical record. The authors calculated the proportion of patients successfully screened and the proportion who reported being nonimmunized. They also compared the patients screened and not screened by the EMS providers and patients who reported being immunized and reported being nonimmunized. RESULTS: Two hundred eighty-eight patients were eligible; the median age was 80 years, 53% were women, 73% were white, and 59% required advanced life support care. Paramedics successfully screened 177 patients (61%; 95% CI, 56-67%). Sixty-five patients (37%; 95% CI, 30-44%) reported being nonimmunized. Failure to screen was associated with a Glasgow Coma Scale score of 13 or less. Lack of immunization was associated with younger age and female gender. CONCLUSION: Paramedics can screen a majority of older adults for influenza immunization status during emergency responses. Older adult users of EMS reported lacking influenza vaccination at levels similar to national estimates. An EMS-based, paramedic-implemented screening program has the potential to identify older adults at risk for preventable illnesses and to augment traditional screening programs, but additional measures are needed to enhance screening rates.

Patients with head injuries refusing emergency medical services transport.

PRIMARY OBJECTIVE: To characterize patients with head injury who refuse emergency medical services (EMS) transport to an emergency department (ED). To identify predictors of patients with head injury who refuse EMS transport. RESEARCH DESIGN: Retrospective chart review. METHODS: Patients with a head injury cared for by EMS during 2001 were identified. Medical records were abstracted for demographic and clinical information and reasons for refusing transport. Patients accepting transport were compared to those refusing. Reasons for refusing transport were described. RESULTS: Three hundred and thirty-three patients with head injuries were identified. Sixteen per cent refused EMS transport. Patients refusing transport were more likely to be male, younger and victims of assault and less likely to have lost consciousness. Patients refusing transport often felt they did not need care or could obtain care later. CONCLUSIONS: Patients with head injuries frequently refuse EMS transportation. Individuals accepting care differ significantly from those refusing care. Sufficient awareness of the risk of head injury seems to be lacking among patients.

Derivation of emergency medical services dispatch codes associated with low-acuity patients.

OBJECTIVE: To identify emergency medical services (EMS) dispatch codes associated with basic life support (BLS) level of prehospital care, a proxy for low illness acuity. METHODS: This retrospective cohort study was conducted in an urban city with a single advanced life support level EMS provider. The 911 center was certified in using dispatch protocols from Priority Dispatch Corporation (Salt Lake City, UT). Dispatch data on all transported EMS patients from August 2001 to April 2002 were abstracted. The authors prospectively defined a low-acuity patient as one who received BLS-level care and defined a low-acuity dispatch code as one in which at least 90% of coded patients required only BLS care. For each dispatch code or code group, the authors calculated the fraction of patients who received BLS-level care. For each "A"-level (lowest category) dispatch code group, the fraction of patients receiving BLS-level care was also evaluated. RESULTS: A total of 19,332 calls met inclusion criteria and were categorized into 118 dispatch codes or code groups. Twenty-eight codes or code groups with 7,801 patients met the authors' definition of low acuity. Overall, 7,394 patients received only BLS care (94.8%, 95% confidence interval: 94.3%-95.3%). Analysis of "A"-level dispatch code groups found BLS use rates of 52.8% to 99.3%. CONCLUSIONS: Certain dispatch codes are associated with the delivery of BLS-level care, indicating identification of patients likely to be low acuity. These codes are not necessarily "A"-level dispatch codes, which are commonly considered to represent the lowest-acuity patients. Future studies are needed to prospectively validate that these codes do represent low-acuity patients.

The utilization of quality assurance methods in emergency medical services

Objectives: The concept of the necessity of a good quality assurance (QA) plan for emergency medical services (EMS) is well-accepted, guide-lines as how best to achieve this and how current systems operate have not been defined. The purpose of this study was to survery EMS systems to discover current methods, used to perform medical control and QA and to examine whether the existence of an emergency medicine residency offected these components Methods: a survery was mailed in 1989 to the major teaching hospitals associated with all of the emergency medicine residency programs and all other hospitals with greater than 350 beds within the 50 largest United States metropolitan areas. The survery consisted of questions concerning four general EMS-QA Categories: 1) general informaction, 2) prospective, 3) immediate and 4) retrospective medical control. Conclusion: This survery characterizes some of the current methods utilized nationwide in EMS-QA programs. Further research is needed to determine the effectiveness of these various methods, and to develop a model program (AU)