Free tissue transfer for burns reconstruction: A single-site experience

This study reviews free tissue transfer (FTT) surgery for both acute wound and reconstructive scar management of burn injuries at a UK burns unit over a 10-year period. Thirty eight patients underwent 46 FTTs, or free flaps, as part of their burn injury pathway. For the cohort of patients, there was one flap failure, which occurred for a secondary scar reconstruction. It is noted that FTT was successful for all seven acute or primary interventions. Anterolateral thigh flap was the most frequently performed (57%); followed by parascapular flaps (22%) of which 43% were pre-expanded. A method of pre-expansion for neck contractures and a novel technique of anchoring this flap to the pre-tracheal fascia are described here. This can provide the patient with good neck contouring by using the capsule to hitch the flap into a good position. It is clear that further work is required to study the prevention of hypertrophic scarring that can occur at the interface between flap and adjacent skin, where occurrence rate in this cohort was 17%. It is proposed that FTT now provides a viable solution both to the coverage of complex burn wounds and to the revision of scar contractures. Consensus over an FTT protocol for the primary management of open burn wounds is seen as the logical next step for this surgical intervention.

A systematic review of prehabilitation programs in abdominal cancer surgery

INTRODUCTION

Prehabilitation programs aim to optimise patients in order to enhance post-operative recovery. This study aims to review the composition of prehabilitation programs for patients undergoing major abdominal cancer surgery and define the outcome measures that are used to evaluate this intervention.

METHODS

A systematic literature review of all comparative studies on prehabilitation versus standard care in patients undergoing abdominal cancer surgery was performed in accordance with PRISMA guidelines. Literature search was performed using Medline, OVID, EMBASE, Google Scholar, and Cochrane databases. Outcomes of interest included prehabilitation program composition (exercise, nutritional, and psychological interventions), duration, mode of delivery, and outcome measures used to determine impact of prehabilitation versus standard care.

RESULTS

9 studies (7 randomised controlled and 2 prospective non-randomised trials) comprising of 549 patients (281 prehabilitation versus 268 standard care) were included in this review. 5 studies reported patients undergoing surgery for colorectal cancer, 2 for bladder tumours, 1 for liver resections, and 1 involving unspecified abdominal oncological operations. The 6 min walk test (6MWT) was used in 4 studies to measure functional capacity with a threshold of >20 m improvement at 4-8 weeks post-operatively deemed significant (distance range from 278 to 560 m). Changes in anaerobic threshold and VO₂^max with prehabilitation were evaluated in 5 studies (ml/kg/min). Health-related quality of life was evaluated using SF-36 system, anxiety assessed using hospital anxiety and depression score (HADS). Post-operative complications were classified according to the Clavien-Dindo classification with no significant difference between prehabilitation and standard care groups.

CONCLUSION

Prehabilitation programs in patients undergoing abdominal cancer surgery remain heterogeneous in their composition, mode of administration, outcome measures of functional capacity that are used to evaluate their impact. All these aspects require standardisation prior to the evaluation of prehabilitation on a larger scale.

Physiologically Based Pharmacokinetic Model to Assess the Influence of Blinatumomab-Mediated Cytokine Elevations on Cytochrome P450 Enzyme Activity

Blinatumomab is a CD19/CD3 bispecific T-cell engager (BiTE®) antibody construct for treatment of leukemia. Transient elevation of cytokines (interleukin (IL)-6, IL-10, interferon-gamma (IFN-γ)) has been observed within the first 48 hours of continuous intravenous blinatumomab infusion. In human hepatocytes, blinatumomab showed no effect on cytochrome P450 (CYP450) activities, whereas a cytokine cocktail showed suppression of CYP3A4, CYP1A2, and CYP2C9 activities. We developed a physiologically based pharmacokinetic (PBPK) model to evaluate the effect of transient elevation of cytokines, particularly IL-6, on CYP450 suppression. The predicted suppression of hepatic CYP450 activities was <30%, and IL-6-mediated changes in exposure to sensitive substrates of CYP3A4, CYP1A2, and CYP2C9 were Collapse

Key Words Collapse

MESH Headings Collapse

Grants Collapse

Affiliation(s)

Y Xu Amgen, Clinical Pharmacology, Modeling and Simulation Group, Department of Medical SciencesThousand Oaks, California, USA
Y Hijazi Amgen Research (Munich)Munich, Germany
A Wolf Amgen Research (Munich)Munich, Germany
B Wu Amgen, Clinical Pharmacology, Modeling and Simulation Group, Department of Medical SciencesThousand Oaks, California, USA
Y-N Sun Amgen, Clinical Pharmacology, Modeling and Simulation Group, Department of Medical SciencesThousand Oaks, California, USA
M Zhu Amgen, Clinical Pharmacology, Modeling and Simulation Group, Department of Medical SciencesThousand Oaks, California, USA

Collapse

Pharmacokinetics and haemodynamics of ketamine in intensive care patients with brain or spinal cord injury

BACKGROUND

Ketamine is used as an anaesthetic agent for short surgical procedures, and as a sedative and analgesic in intensive care patients. Intensive care patients with brain or spinal cord injury may have physiological changes that could alter the pharmacokinetics of ketamine. The pharmacokinetics of ketamine have been studied in healthy volunteers and in patients undergoing different types of surgery, but no data are available in intensive care patients.

METHODS

We determined the pharmacokinetics of ketamine and its active metabolites, norketamine and dehydronorketamine, in 12 intensive care patients with brain or spinal cord injury. The effect of ketamine on haemodynamic variables was also investigated.

RESULTS

The total clearance of ketamine, mean (SD), was 36.0 (13.3) ml min(-1) kg(-1), the volume of distribution (Vbeta) was 16.0 (8.6) litre kg(-1), and the elimination half-life was 4.9 (1.6) h. Ketamine did not alter any haemodynamic variables in the patients studied.

CONCLUSIONS

Pharmacokinetic variables of ketamine in intensive care patients are greater than in healthy volunteers and in surgical patients. The increase in the volume of distribution is greater than the increase in clearance, resulting in a longer estimated half-life of ketamine in this patient group.

Seroprevalence of West Nile, Rift Valley, and sandfly arboviruses in Hashimiah, Jordan

We conducted a serosurvey among patients of a health center in Hashimiah, a Jordanian town of 30,000 inhabitants located near a wastewater treatment plant and its effluent channel. Serum samples from 261 patients >/=5 years of age were assessed for immunoglobulin G (IgG) and IgM antibodies against West Nile, sandfly Sicilian, sandfly Naples, and Rift Valley viruses; the seroprevalence of IgG antibodies was 8%, 47%, 30%, and 0%, respectively. Female participants were more likely to have been infected than male. Persons living within 2 km of the treatment plant were more likely to have been infected with West Nile (p=0.016) and sandfly Sicilian (p=0.010) viruses. Raising domestic animals within the house was a risk factor for sandfly Sicilian (p=0.003) but not for sandfly Naples virus (p=0.148). All serum samples were negative for IgM antibodies against the tested viruses. Our study is the first documentation of West Nile and sandfly viruses in Jordan and calls attention to the possible health hazards of living close to wastewater treatment plants and their effluent channels.

Neuroectodermal differentiation in Ewing's sarcoma family of tumors does not predict tumor behavior

The observation that neuroectodermal differentiation imparts a worse prognosis to the Ewing family of tumors has been suggested by some studies and refuted by others. To assess whether the diagnosis of Ewing's sarcoma versus peripheral primitive neuroectodermal tumor (PNET) affects prognosis, we analyzed tumors from 63 analogously treated pediatric and young adult patients from the National Cancer Institute and St Jude Children's Research Hospital and retrospectively compared the results with clinical outcomes. The tumors were assessed using standard light microscopy and immunohistochemical stains for neuron-specific enolase, CD57, S100 protein, neurofilament protein, and synaptophysin with or without antigen retrieval. Ultrastructural evaluation was also performed in 39 tumors. Classification was performed using Kiel criteria as well as a modified classification. Kaplan-Meier analyses, with Mantel-Haenzel evaluation of the significance of the differences, were performed separately for localized or metastatic tumors. Using the Kiel classification on a subset of 60 cases, 39 tumors qualified as PNET and 21 as Ewing's sarcoma. Using the modified classification on a subset of 61 cases, 14 were classified as PNET, 21 as atypical Ewing's sarcoma, and 26 as Ewing's sarcoma. The addition of electron microscopy to the diagnostic armamentarium significantly increased the likelihood of identifying PNET. No significant differences in event-free or overall survival were seen using either the modified or Kiel classification, regardless of the ancillary diagnostic techniques employed. In this exploratory analysis, neuroectodermal differentiation did not play a role in clinical outcome. Confirmation of this finding will require a larger, separate study of similarly treated patients, and it may not apply to older patients.

Use of recombinant poxviruses to stimulate anti-melanoma T cell reactivity

BACKGROUND

Dendritic cells (DC) are potent professional antigen-presenting cells that can activate naive T lymphocytes and initiate cellular immune responses. As adjuvants, DC may be useful for enhancing immunogenicity and mediating tumor regression. Endogenous expression of antigen by DC could offer the potential advantage of allowing prolonged constitutive presentation of endogenously processed epitopes and exploitation of multiple restriction elements for the presentation of the same antigen.

METHODS

DC were prepared from the peripheral blood of HLA A*0201 patients with metastatic melanoma in the presence of IL-4 (1000 IU/mL) and GMCSF (1000 IU/mL). Recombinant vaccinia and fowlpox viruses encoding the hMART-1 gene were constructed and used to infect DC. The efficiency of infection and expression of the MART-1 antigen were assessed by immunohistochemistry and intracellular FACS analyses. Cytotoxic lymphocytes (CTL) were generated by the stimulation of CD8+ T cells, with DC expressing the recombinant gene. Reactivity of the CTL was determined at weeks 1 and 2 by the amount of IFN-gamma released.

RESULTS

DC were infected with recombinant poxviruses and demonstrated specific melanoma antigen expression by immunohistochemistry, immunofluorescence, and intracellular FACS analysis. The expression by DC of MART-1 MAA after viral infection was sufficient to generate CD8+ T lymphocytes that recognized naturally processed epitopes on tumor cells in 10 of 11 patients.

CONCLUSIONS

Human DC are receptive to infection by recombinant poxviruses encoding MAA genes and are capable of efficiently processing and presenting these MAA to cytotoxic T cells. The potential advantage of this approach is the ability to present specific antigen independent of the identification of the epitope or the MHC restriction element. This strategy may be useful for the identification of relevant epitopes for a diverse number of HLA alleles and for active immunization in patients.

Oncocytic nodular hidradenoma

Oncocytic neoplasms are most commonly of salivary, thyroid, parathyroid, and renal origin. Ocular adnexal tumors with oncocytosis have been reported. We report an unusual example of a skin adnexal tumor from the back. A tumor of uncertain duration was excised from a 54-year-old man. Light microscopy of hematoxylin and eosin-stained sections showed a large, fairly well-defined cystic nodular hidradenoma with areas infiltrated by numerous closely arranged, large, uniform, oval and polygonal cells with abundant intensely eosinophilic cytoplasm and small central, dark, round nuclei. No significant cellular atypia or mitotic figures were observed. The cytoplasm of these cells showed markedly positive immunostaining with monoclonal antimitochondrial antibodies. Electron microscopy demonstrated cytoplasm packed with mitochondria. Pure oncocytic tumors usually follow a benign clinical course. The focal presence of oncocytes in an otherwise histologically recognizable tumor apparently does not affect the prognosis, which in this case is the favorable outcome expected for a nodular hidradenoma.