Ongoing effects of preterm birth on the dopaminergic and noradrenergic pathways in the frontal cortex and hippocampus of guinea pigs.

Children born preterm have an increased likelihood of developing neurobehavioral disorders such as attention-deficit hyperactivity disorder (ADHD) and anxiety. These disorders have a sex bias, with males having a higher incidence of ADHD, whereas anxiety disorder tends to be more prevalent in females. Both disorders are underpinned by imbalances to key neurotransmitter systems, with dopamine and noradrenaline in particular having major roles in attention regulation and stress modulation. Preterm birth disturbances to neurodevelopment may affect this neurotransmission in a sexually dimorphic manner. Time-mated guinea pig dams were allocated to deliver by preterm induction of labor (gestational age 62 [GA62]) or spontaneously at term (GA69). The resultant offspring were randomized to endpoints as neonates (24 h after term-equivalence age) or juveniles (corrected postnatal day 40, childhood equivalence). Relative mRNA expressions of key dopamine and noradrenaline pathway genes were examined in the frontal cortex and hippocampus and quantified with real-time PCR. Myelin basic protein and neuronal nuclei immunostaining were performed to characterize the impact of preterm birth. Within the frontal cortex, there were persisting reductions in the expression of dopaminergic pathway components that occurred in preterm males only. Conversely, preterm-born females had increased expression of key noradrenergic receptors and a reduction of the noradrenergic transporter within the hippocampus. This study demonstrated that preterm birth results in major changes in dopaminergic and noradrenergic receptor, transporter, and synthesis enzyme gene expression in a sex- and region-based manner that may contribute to the sex differences in susceptibility to neurobehavioral disorders. These findings highlight the need for the development of sex-based treatments for improving these conditions.

Neurodevelopmental follow-up of preterm infants: current practice for infants at a tertiary neonatal centre.

AIM: To characterise neurodevelopmental surveillance, assessment and outcomes for infants at risk of adverse neurodevelopment and inform targeted surveillance of infants discharged from a regional tertiary neonatal centre. METHODS: A retrospective study of developmental follow-up of 106 vulnerable infants born either preterm (23-29 weeks gestation, n=96) or at ≥30 weeks gestation with low birth weight (<1,200 grams n=10) admitted to our tertiary Neonatal Intensive Care Unit between January 2011 and December 2015. Infants transferred to other regions before two-years corrected postnatal age were excluded. Local health records were reviewed to determine neurodevelopmental follow-up, input and outcomes. RESULTS: Almost all (98%) of high-risk infants received at least one follow-up visit by a visiting neurodevelopmental therapist following discharge from the neonatal unit, and 73% of infants received early developmental follow-up in line with international recommendations. Ninety infants (87%) were seen until at least two years post term, at which point 61 (68%) had typical development. At five-years post term, 23 (26%) of the 89 infants remaining in the region had been diagnosed with a developmental disability, for which global developmental disability was the most common diagnosis (19 infants). CONCLUSION: Routine neurodevelopmental surveillance of vulnerable infants from our tertiary catchment has high coverage, with most infants receiving regular developmental assessment. However, universal developmental screening is resource intense, and overall rates of diagnosed neurodevelopmental impairment are relatively low. Better early identification of infants most at risk using earlier assessment tools may help to stratify and target follow-up to allow resources to be allocated more effectively and reduce the follow-up burden for infants at lower risk of developmental concerns.

Early identification of infants at risk of cerebral palsy: developing the use of general movement assessment in routine clinical practice in a tertiary neonatal unit in New Zealand.

BACKGROUND: Preterm infants have a high risk of neurodevelopmental disability, including cerebral palsy (CP). Often, CP is not diagnosed until after 12 months, leading to delay in targeted interventions. The General Movements assessment (GM) evaluates the spontaneous movements of high-risk infants from birth to 20 weeks corrected postnatal age (CPA), and accurately predicts the risk of CP. This allows for earlier diagnosis and intervention, potentially changing the trajectory of disability, yet routine use of GM is not well established in New Zealand. AIM: To describe the process of setting up GM in a tertiary neonatal unit. METHODS: We reviewed the process and progress made to date setting up GM in our service. RESULTS: Challenges and potential solutions for the implementation of GM were identified. Key areas of development included staff training and support, IT services, resources, medical documentation, inter-departmental communication and establishing clinical pathways. CONCLUSION: GM has become successfully integrated into the assessment of high-risk infants in our neonatal unit, with the aim to provide valuable information to health professionals and families to optimise intervention and improve outcomes. Efforts will continue to ensure there is robust and sustainable system for using GM in our service.

Respiratory health inequality starts early: The impact of social determinants on the aetiology and severity of bronchiolitis in infancy.

AIM: To define the impact of demographics on the incidence, aetiology and clinical course of viral bronchiolitis in infants younger than 2 years of age. METHODS: Retrospective case review of all viral bronchiolitis admissions for patients aged younger than 2 years old from January 1 2014 to 31 December 2015 at Wellington Regional Hospital, New Zealand. Demographic data, second-hand smoke exposure (SHSE) and presence of predisposing conditions were collected, along with outcome data including use of respiratory support and intensive care unit (ICU) admission. This was compared to background rates calculated from regional census data. RESULTS: There were 556 admissions included (11% of paediatric medical admissions); 49% tested positive for respiratory syncytial virus (RSV) (84% tested), and 40% of admissions received positive pressure respiratory support and 10% ICU admission. Admission rates ranged from 9.6 to 77 per 1000/year, with higher rates seen in those from areas of high deprivation. Admission rates by deprivation varied according to aetiology. RSV-positive admission rates increased from 9.7 per 1000/year to 24.6 per 1000/year in the least to most deprived areas, whereas non-RSV admissions showed even greater disparity, increasing from 10.1 per 1000/year to 37.5 per 1000/year (both P < 0.0001). CONCLUSIONS: This study further reinforces that material deprivation contributes significantly to poor health outcomes that are apparent in infancy. SHSE is a potent risk factor for adverse respiratory outcomes in this patient population. Ongoing efforts to eradicate smoking and reduce material inequality need to continue.

Endovascular treatment of acute portal vein thrombosis using ultrasound-accelerated catheter-directed thrombolysis.

We report a case of extensive acute portal vein thrombosis (PVT) presenting with severe diffuse abdominal pain and impending small bowel infarction. The patient was successfully treated with ultrasound-accelerated catheter-directed thrombolysis (EKOS endowave system; Covidien, Mansfield, Massachusetts), which resulted in prompt recanalization of his portal vein (PV) and its tributaries. The patient eventually had ischemic stricture that necessitated bowel resection. However, we believe that our technique was successful in rapidly restoring the patency of the PV and its tributaries, and therefore, avoiding a life-threatening complication of more extensive bowel infarction. To our knowledge, the use of ultrasound-accelerated thrombolysis in treatment of PVT has not been previously described in the literature.

A single CT for attenuation correction of both rest and stress SPECT myocardial perfusion imaging: a retrospective feasibility study.

PURPOSE: In the effort to reduce radiation exposure to patients undergoing myocardial perfusion imaging (MPI) with SPECT/CT, we evaluate the feasibility of a single CT for attenuation correction (AC) of single-day rest (R)/stress (S) perfusion. METHODS: Processing of 20 single isotope and 20 dual isotope MPI with perfusion defects were retrospectively repeated in three steps: (1) the standard method using a concurrent R-CT for AC of R-SPECT and S-CT for S-SPECT; (2) the standard method repeated; and (3) with the R-CT used for AC of S-SPECT, and the S-CT used for AC of R-SPECT. Intra-Class Correlation Coefficients (ICC) and Choen's kappa were used to measure intra-operator variability in sum scoring. RESULTS: The highest level of intra-operator reliability was seen with the reproduction of the sum rest score (SRS) and sum stress score (SSS) (ICC > 95%). ICCs were > 85% for SRS and SSS when alternate CTs were used for AC, but when sum difference scores were calculated, ICC values were much lower (~22% to 27%), which may imply that neither CT substitution resulted in a reproducible difference score. Similar results were seen when evaluating dichotomous outcomes (sum scores difference of ≥ 4) when comparing different processing techniques (kappas ~0.32 to 0.43). CONCLUSIONS: When a single CT is used for AC of both rest and stress SPECT, there is disproportionately high variability in sum scoring that is independent of user error. This information can be used to direct further investigation in radiation reduction for common imaging exams in nuclear medicine.

A modern series of percutaneous intracavitary instillation of amphotericin B for the treatment of severe hemoptysis from pulmonary aspergilloma.

BACKGROUND: Pulmonary aspergillomas may cause life-threatening hemoptysis. The treatment of this condition is problematic because poor pulmonary function often precludes definitive surgical resection. METHODS: We retrospectively reviewed all patients hospitalized at our institution for hemoptysis associated with an aspergilloma over an 8-year period and who underwent percutaneous intracavitary instillation of amphotericin B (ICAB). ICAB consisted of catheter placement into the aspergilloma cavity with subsequent instillation of 50 mg amphotericin B in 20 mL 5% dextrose solution daily for 10 days. RESULTS: ICAB was attempted for 23 distinct episodes of severe hemoptysis in 20 individual patients. Catheter placement was successful in 21 of the 23 episodes (91%), and of these, ICAB instillation was successfully completed in 20 episodes (95%). In these 20 episodes, hemoptysis ceased by hospital discharge in 17 of 20 patients (85%) and in all 18 who survived until a follow-up visit 1-month after treatment. Pneumothorax occurred in six of 23 (26%) catheter placement attempts without long-term complications. Recurrence of serious hemoptysis occurred after six of 18 episodes for which follow-up was available. Potential risk factors associated with severe, recurrent hemoptysis were a size increase or reappearance of the aspergilloma on a chest CT scan (P = .001), bleeding diathesis (P = .08), and lack of bronchial artery embolization during index hospitalization (P = .07). CONCLUSIONS: Our data suggest that ICAB is an effective short-term treatment to control severe hemoptysis caused by pulmonary aspergilloma. The long-term benefit of this procedure is unknown. We identified several potential risk factors for recurrent hemoptysis after ICAB that could be examined prospectively in future trials.

Acquisition of endovascular skills for uterine artery embolization using a simulator.

This study addresses endovascular training using simulators for uterine artery embolization. A review of endovascular skill training for surgeons using simulators was performed. Surgeons possess varying levels of proficiency in endovascular techniques. A simulator will improve endovascular skills in the following areas: C-arm image intensifier use, catheter selection and manipulation, understanding of the pelvic anatomy, and technique of embolization. Surgeons may gain realistic experience on the simulator prior to entry into the cath lab or procedure room. Using a simulator, surgeons can learn valuable endovascular skills necessary for successful performance of uterine artery embolization.

Endovascular training with animals versus virtual reality systems: an economic analysis.

PURPOSE: To assess the relative costs of a virtual reality (VR) laboratory and an animal laboratory for endovascular skills training. MATERIALS AND METHODS: Cost data extracted from a previous experiment was used to perform a financial analysis according to the guidelines published by the National Institutes of Health. The analysis compared the purchase or rental of a Procedicus Vascular Interventional System Trainer to the rental of an animal laboratory. RESULTS: The VR laboratory course cost $3,434 per trainee versus $4,634 in the animal laboratory according to the purchase-versus-rental analysis. The cost ratio was 0.74 in favor of the VR laboratory. Cost ratio sensitivity analysis ranged from 0.25 in favor of the VR laboratory to 2.22 in favor of the animal laboratory. The first-year potential savings were $62,410 assuming exclusive use of the VR laboratory. The 5-year training savings totaled $390,376, excluding the $60,000 residual value of the simulator. Simulator rental reduced the course price to $1,076 per trainee and lowered the cost ratio to 0.23 in favor of the VR laboratory. Findings of sensitivity analysis ranged from 0.08 to 0.70 in favor of the VR laboratory. The first-year and 5-year potential national savings increased to $185,026 and $1,013,238, respectively. CONCLUSIONS: Although evidence remains sparse that the training of interventional skills in artificial environments translates to better performance in human procedures, there are good pedagogic grounds on which to believe that such training will become increasingly important. The present comparison of the direct costs of two such models suggests that VR training is less expensive than live animal training.

Porcine transfer study: virtual reality simulator training compared with porcine training in endovascular novices.

PURPOSE: To compare the learning of endovascular interventional skills by training on pig models versus virtual reality simulators. METHODS: Twelve endovascular novices participated in a study consisting of a pig laboratory (P-Lab) and a virtual reality laboratory (VR-Lab). Subjects were stratified by experience and randomized into four training groups. Following 1 hr of didactic instruction, all attempted an iliac artery stenosis (IAS) revascularization in both laboratories. Onsite proctors evaluated performances using task-specific checklists and global rating scales, yielding a Total Score. Participants completed two training sessions of 3 hr each, using their group's assigned method (P-Lab x 2, P-Lab + VR-Lab, VR-Lab + P-Lab, or VR-Lab x 2) and were re-evaluated in both laboratories. A panel of two highly experienced interventional radiologists performed assessments from video recordings. ANCOVA analysis of Total Score against years of surgical, interventional radiology (IR) experience and cumulative number of P-Lab or VR-Lab sessions was conducted. Inter-rater reliability (IRR) was determined by comparing proctored scores with the video assessors in only the VR-Lab. RESULTS: VR-Lab sessions improved the VR-Lab Total Score (beta = 3.029, p = 0.0015) and P-Lab Total Score (beta = 1.814, p = 0.0452). P-Lab sessions increased the P-Lab Total Score (beta = 4.074, p < 0.0001) but had no effect on the VR-Lab Total Score. In the general statistical model, both P-Lab sessions (beta = 2.552, p = 0.0010) and VR-Lab sessions (beta = 2.435, p = 0.0032) significantly improved Total Score. Neither previous surgical experience nor IR experience predicted Total Score. VR-Lab scores were consistently higher than the P-Lab scores (Delta = 6.659, p < 0.0001). VR-Lab IRR was substantial (r = 0.649, p < 0.0008). CONCLUSIONS: Endovascular skills learned in the virtual environment may be transferable to the real catheterization laboratory as modeled in the P-Lab.

Assessment of a virtual interventional simulator trainer.

PURPOSE: To assess the construct validity of the Procedicus Virtual Interventional Simulator Trainer (Procedicus-VIST) and its use as a training tool. METHODS: Two groups comprised of 8 interventional radiologists (experts) and 8 medical students (novices) performed 6 renal artery procedures on the Procedicus-VIST. All participants received a 45-minute standardized didactic introduction before starting the simulations. The first 2-hour session was used for familiarization, whereas the second session constituted the testing period. During each procedure, objective performance data including procedure time, fluoroscopic time, contrast, cine loops, lesion coverage, tool:lesion ratio, placement accuracy, and residual stenosis were recorded by the Procedicus-VIST software. Exit surveys were completed to document demographic and subjective data. A visual analogue scale (VAS) from 0 to 100 was used to rate total, guidewire, catheter, balloon, stent, fluoroscopic, and joystick realism, as well as the simulator's pedagogic value. RESULTS: There were no significant differences in performances between the 2 groups in residual stenosis, placement accuracy, procedure time, number of cine loops, lesion coverage, or tool:lesion ratio. The total fluoroscopic use was greater for the novice group (p < 0.01). Experts rated 6 of the 8 subjective parameters favorably, whereas the novice group approved of 7. CONCLUSIONS: Using this study design, the quantitative metrics recorded by the Procedicus-VIST software failed to stratify performances based upon experience level, with the exception of fluoroscopic use. Investigation comparing standard training to virtual reality training should be performed to assess any differences in actual performance in the catheterization laboratory.