Thoracic Interfascial Plane Blocks and Outcomes After Minithoracotomy for Valve Surgery.

Introduction. Thoracic interfascial plane blocks are increasingly used for pain management after minimally invasive thoracotomy for valve repair and replacement procedures. We hypothesized that the addition of these blocks to the intercostal nerve block injected by the surgeon would further reduce pain scores and opioid utilization. Methods. In this retrospective cohort study, 400 consecutive patients who underwent minimally invasive thoracotomy for mitral or aortic valve replacement and were extubated within 2 hours of surgery were enrolled. The maximum pain score and opioid utilization on the day of surgery and other outcome variables were compared between patients who received interfascial plane blocks and those who did not. Results.193 (48%) received at least one interfascial plane block while 207 (52%) received no interfascial plane block. Patients who received a thoracic interfascial plane block had a maximum VAS score on the day of surgery (mean 7.4 ± 2.5) after the block was administered which was significantly lower than patients in the control group who did not receive the block (mean 7.9 ± 2.2) (P = .02). Opioid consumption in the interfascial plane block group on the day of surgery was not significantly different from the control group. Conclusion. Compared to intercostal blocks alone, the addition of thoracic interfascial plane blocks was associated with a modest reduction in maximum VAS score on the day of surgery. However, no difference in opioid consumption was noted. Patients who received interfascial plane blocks also had decreased blood transfusion requirements and a shorter hospital length of stay.

Effect of vitrification on mechanical properties of porcine articular cartilage.

Articular cartilage (AC) injuries do not heal primarily and large lesions progress to degenerative osteoarthritis. Osteochondral allograft transplantation is an effective surgical treatment but is limited by the lack of donor tissue availability. Fresh allografts can be stored hypothermically up to 28-45 days after which the tissue is no longer viable for transplantation. Vitrification is a method of cryopreservation with the potential to extend the storage time of AC. A specific protocol has been demonstrated to preserve high chondrocyte viability; however, its effect on various mechanical properties of the extracellular matrix (ECM) remains unknown and is the focus of this initial study. Porcine AC was subject to a defined vitrification protocol, using fresh and frozen samples as positive and negative controls, respectively; n = 20 for all three groups. Unconfined compression testing was used to assess mechanical properties of the tissue under rapid load, stress relaxation, and equilibrium conditions. The stress relaxation time constants (modeled with a 2-term Prony series) τ1 and τ2 were significantly lower for frozen (p = 0.014, p < 0.001) and vitrified (p = 0.009, p = 0.003) tissue compared to fresh, with no differences between frozen and vitrified samples (p = 0.848 and 0.105 for τ1 and τ2, respectively). These values indicate that frozen and vitrified samples relaxed more rapidly than fresh, which may suggest altered matrix composition and permeability post-treatment. These results represent the initial study in our experimental path to evaluate differences in mechanical properties of vitrified tissues.

Unrecognised Outbreak: Human parainfluenza virus infections in a pediatric oncology unit. A new diagnostic PCR and virus monitoring system may allow early detection of future outbreaks.

Background: Human parainfluenza viruses (HPIVs) are significant causes of both upper and lower respiratory tract infections with type 3 (HPIV3) causing the most severe disease in the immunocompromised cohorts.  The objective of this study was to analyse the epidemiological nature of a cluster of cases of HPIV3 in a pediatric oncology unit of a major teaching hospital. Methods: In order to determine whether the activity observed represented a deviation from the norm, seasonal trends of HPIV3 in the surrounding geographical area as well as on the ward in question were analysed.  The genetic link between cases was established by the phylogenetic analysis of the non-coding hypervariable region between the M (Matrix) and F (fusion) genes of HPIV3. The 15 cases involved and 15 unrelated cases were sequenced.  Transmission routes were subsequently inferred and visualized using Konstanz Information Miner (KNIME) 3.3.2. Results: Of the 15 cases identified, 14 were attributed to a point source outbreak. Two out of 14 outbreak cases were found to differ by a single mutation A182C. The outbreak strain was also seen in 1 out of 15 unrelated cases, indicating that it was introduced from the community. Transmission modeling was not able to link all the cases and establish a conclusive chain of transmission. No staff were tested during the outbreak period. No deaths occurred as a result of the outbreak. Conclusion: A point source outbreak of HPIV3 was recognized post factum on an oncology pediatric unit in a major teaching hospital. This raised concern about the possibility of a future more serious outbreak. Weaknesses in existing systems were identified and a new dedicated respiratory virus monitoring system introduced.  Pediatric oncology units require sophisticated systems for early identification of potentially life-threatening viral outbreaks.

Alpha Thalassemia/Mental Retardation Syndrome X-Linked, the Alternative Lengthening of Telomere Phenotype, and Gliomagenesis: Current Understandings and Future Potential.

Gliomas are the most common primary malignant brain tumor in humans. Lower grade gliomas are usually less aggressive but many cases eventually progress to a more aggressive secondary glioblastoma (GBM, WHO Grade IV), which has a universally fatal prognosis despite maximal surgical resection and concurrent chemo-radiation. With the identification of molecular markers, however, there is promise for improving diagnostic and therapeutic strategies. One of the key molecular alterations in gliomas is the alpha thalassemia/mental retardation syndrome X-linked (ATRX) gene, which is frequently mutated. One-third of pediatric GBM cases are also found to have the ATRX mutation and the genetic signatures are different from adult cases. The exact role of ATRX mutations in gliomagenesis, however, is unclear. In this review, we describe the normal cellular function of the ATRX gene product followed by consequences of its dysfunction. Furthermore, its possible association with the alternative lengthening of telomeres (ALT) phenotype is outlined. Lastly, therapeutic options potentiated through a better understanding of ATRX and the ALT phenotype are explored.