Protective effects of dexmedetomidine on ischaemia-reperfusion injury in an experimental rat model of priapism

The study aimed to investigate the effects of dexmedetomidine against ischaemia-reperfusion injury occurring after priapism in a model of induced-priapism in rats. A total of 18 male rats were randomised into three groups. Group 1 was the control group. A priapism model was performed rats in Group 2 and then ischaemia-reperfusion injury was evaluated. Group 3 had similar procedures to the rats in Group 2. Rats in Group 3 additionally had 100 μg/kg dexmedetomidine administered intraperitoneally immediately after reperfusion. Blood and tissue samples were analysed. Biochemical analysis of blood samples revealed a decrease in the levels of the pro-inflammatory cytokines including interleukin-1 beta (IL-1 Beta), interleukin-6 (IL-6), and tumour necrosis factor-alpha (TNF-alpha) in Group 3 compared to Group 2 (p:.04, p:.009 and p:.009, respectively). Similarly, the highest malondialdehyde (MDA) level was in Group 2 (p:.002). The levels of antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were significantly higher in Group 3 than that of Group 2 (p:.037 and p:.045, respectively). Direct microscopic examinations revealed positive changes in desquamation, oedema, inflammation and vasocongestion scores in Group 3 compared to Group 2 (p:.007, p:.008, p:.007 and p:.006, respectively). Dexmedetomidine has a protective effect against ischaemia-reperfusion injury in penile tissue.     

Comparative study of different transplantation methods of adipose tissue-derived stem cells in the treatment of erectile dysfunction caused by cavernous nerve injury

We aimed to compare intracavernosal injection (ICI), tail vein injection (IV), and periprostatic injection (PPI) of adipose-derived stem cells (ADSCs) for their ability to improve erectile function in cavernous nerve injury-induced erectile dysfunction (CNIED) rats and to explore the possible mechanism. Eighty-four male SD rats were divided into the sham group (n = 6), BCNI group (bilateral CN crush injury, n = 6), PBS-ICI group (n = 6), PBS-IV group (n = 6), PBS-PPI group (n = 6), ADSC-ICI group (n = 18), ADSC-IV group (n = 18) and ADSC-PPI group (n = 18). ADSCs were labelled with 5-ethynyl-2′-deoxyuridine (EdU), and six rats each in the ADSC-ICI group, ADSC-IV group, and ADSC-PPI group were sacrificed 2, 7, and 28 days after injection. EdU-labelled ADSCs were tracked by immunofluorescence staining. The intracavernosal pressure (ICP)/mean arterial pressure (MAP) ratio, neuronal nitric oxide synthase (nNOS)-positive nerve fibres in the dorsal penile nerve and the smooth muscle/collagen ratio in the cavernosum between groups were also evaluated. ADSCs can significantly improve erectile function through ICI or IV. The two are similar in efficacy and superior to PPI. The mechanism may be that after CN injury, ADSCs are recruited to around the MPG and secrete a variety of neurotrophic factors that promote the repair of the CN, thereby improving erectile function.     

The effects of pirfenidone on ischaemia–reperfusion injury in testicular torsion-induced rat model

The aim of this study was to analyse the effect of pirfenidone against ischaemia–reperfusion injury occurring after detorsion in rats with induced testicular torsion model. Group 1 was assigned as the control group. Group 2 first had testis torsion performed, and then, testicular detorsion was performed. Group 3 had similar procedures to the rats in Group 2. Rats in Group 3 additionally had 325 mg/kg pirfenidone administered immediately after ischaemia. The blood samples were analysed spectrophotometrically. To determine the intensity of tissue injury, haemorrhage, oedema and congestion levels were evaluated with direct microscopic investigation of testis. Seminiferous tubule architecture, spermatogenesis processes and germ cell maturation were graded by Johnsen and Cosentino scoring systems. In Group 3, superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities increased compared with Group 2 (p:.03 and p:.049 respectively). Additionally, the mean malondialdehyde (MDA) value was higher in Group 2 compared with the other groups (p:.001). Histopathological investigation of rats in Group 3 identified positive changes in haemorrhage, oedema and congestion levels compared with Group 2 (p:.031, p:.048, p:.044 respectively). Similarly, Johnsen and Cosentino scores were positively affected in Group 3 (p:.033, p:.032 respectively). Pirfenidone is protective against testicular oxidative damage.     

Soluble suppression of tumorigenicity-2 predicts pneumonia in patients with inhalation injury: Results of a pilot study

IntroductionSeveral mechanisms play a role in the development of pneumonia after inhalation injury. Our aim was to analyze whether higher concentrations of inflammatory markers or of biomarkers of epithelial injury are associated with a higher incidence of pneumonia in patients with inhalation injury.Material and methodsSecondary analysis of a single-center prospective observational cohort pilot study, performed over a two-year period (2015–2017) at the Burns Unit of the Plastic and Reconstructive Surgery Department of Vall d’Hebron University Hospital. All patients aged 18 with suspected inhalation injury undergoing admission to the Burns Unit were included. Plasma biomarkers of the lung epithelium (RAGE and SP-D), inflammation markers (IL6, IL8), and IL33, as well as soluble suppression of tumorigenicity-2 (sST2) levels, were measured within the first 24 h of admission.ResultsTwenty-four patients with inhalation injury were included. Eight (33.3%) developed pneumonia after a median of 7 (4–8) days of hospital stay. Patients with pneumonia presented higher plasma concentrations of sST2 (2853 [2356–3351] ng/mL vs 1352 [865–1839] ng/mL; p < 0.001), IL33 (1.95 [1.31–2.59] pg/mL vs 1.26 [1.07–1.45] pg/mL; p = 0.002) and IL8 (325.7 [221.6–430.0] pg/mL vs 174.1 [95.2–253.0] pg/mL; p = 0.017) on day 1 of inclusion. Plasma sST2 concentration in the first 24 h demonstrated excellent diagnostic accuracy for predicting the occurrence of pneumonia in patients with smoke inhalation (AUROC 0.929 [95%CI 0.818–1.000]). A cutoff point of ≥2825 ng/mL for sST2 had a sensitivity of 75% and a specificity of 100%. The risk ratio of pneumonia in patients with sST2 ≥ 2825 ng/mL was 7.14 ([95% CI 1.56–32.61]; p = 0.016).ConclusionsPlasma sST2 in the first 24 h of admission predicts the occurrence of pneumonia in patients with inhalation injury.     

Mathematical model of volume kinetics and renal function after burn injury and resuscitation

This paper presents a mathematical model of blood volume kinetics and renal function in response to burn injury and resuscitation, which is applicable to the development and non-clinical testing of burn resuscitation protocols and algorithms. Prior mathematical models of burn injury and resuscitation are not ideally suited to such applications due to their limited credibility in predicting blood volume and urinary output observed in wide-ranging burn patients as well as in incorporating contemporary knowledge of burn pathophysiology. Our mathematical model consists of an established multi-compartmental model of blood volume kinetics, a hybrid mechanistic-phenomenological model of renal function, and novel lumped-parameter models of burn-induced perturbations in volume kinetics and renal function equipped with contemporary knowledge on burn-related physiology and pathophysiology. Using the dataset collected from 16 sheep, we showed that our mathematical model can be characterized with physiologically plausible parameter values to accurately predict blood volume kinetic and renal function responses to burn injury and resuscitation on an individual basis against a wide range of pathophysiological variability. Pending validation in humans, our mathematical model may serve as an effective basis for in-depth understanding of complex burn-induced volume kinetic and renal function responses as well as development and non-clinical testing of burn resuscitation protocols and algorithms.     

Variation in acute fluid resuscitation among pediatric burn centers

BackgroundAccurate resuscitation of pediatric patients with large thermal injury is critical to achieving optimal outcomes. The goal of this project was to describe the degree of variability in resuscitation guidelines among pediatric burn centers and the impact on fluid estimates.MethodsFive pediatric burn centers in the Pediatric Injury Quality Improvement Collaborative (PIQIC) contributed data from patients with ≥15% total body surface area (TBSA) burns treated from 2014 to 2018. Each center's resuscitation guidelines and guidelines from the American Burn Association were used to calculate estimated 24-h fluid requirements and compare these values to the actual fluid received.ResultsDifferences in the TBSA burn at which fluid resuscitation was initiated, coefficients related to the Parkland formula, criteria to initiate dextrose containing fluids, and urine output goals were observed. Three of the five centers’ resuscitation guidelines produced statistically significant lower mean fluid estimates when compared with the actual mean fluid received for all patients across centers (4.53 versus 6.35 ml/kg/% TBSA, p < 0.001), (4.90 versus 6.35 ml/kg/TBSA, p = 0.002) and (3.38 versus 6.35 ml/kg/TBSA, p < 0.0001).ConclusionsThis variation in practice patterns led to statistically significant differences in fluid estimates. One center chose to modify its resuscitation guidelines at the conclusion of this study.     

Decreased neuroplasticity in minor burn injury survivors compared to non-injured adults: A pilot study in burn injury survivors aged 45 years and older

ObjectiveNeuroplasticity is the capacity of the brain to change or adapt with experience: brain changes occur with use, disuse, and injury. Repetitive transcranial magnetic stimulation (rTMS) can be used to induce neuroplasticity in the human brain. Here, we examined rTMS-induced neuroplasticity in the primary motor cortex in burns survivors and controls without injury, and whether neuroplasticity is associated with functional recovery in burns survivors.MethodsSixteen burn injury survivors (total body surface area of burn injury <15%) and 13 non-injured control participants were tested. Repetitive TMS (specifically, spaced continuous theta-burst stimulation[cTBS]) was applied to induce neuroplasticity 6 and 12 weeks after injury in burn survivors and in two sessions separated by 6 weeks in controls. Motor evoked potentials (MEPs) elicited by single-pulse TMS were measured before and after rTMS to measure neuroplasticity. Burns survivors completed a functional assessment 12 weeks after injury.ResultsNon-injured controls showed decreased MEP amplitude 15?30 min after spaced cTBS in both experimental sessions. Burn survivors showed a smaller change in MEP amplitude after spaced cTBS compared to controls 6 weeks after burn injury but no difference compared to controls 12 weeks after burn injury. In burn survivors, there was a significant positive association between general health outcome (Short-Form Health Survey) and the change in MEP amplitude after spaced cTBS 12 weeks after injury (r=.73, p = .01).ConclusionsThe current findings suggest that burn survivors have a reduced capacity for neuroplasticity early in the recovery period (6 weeks after injury), which normalizes later in the recovery period (12 weeks after injury). Furthermore, the results provide preliminary evidence to suggest that burn survivors with normalized neuroplasticity 12 weeks after injury recover faster after burn injury.     

Point-of-care measured serum cholinesterase activity predicts patient outcome following severe burns

Risk stratification is of utmost importance in burn therapy. However, suitable bedside biomarkers to evaluate the emerging inflammatory response following burn injuries are missing. Serum cholinesterase (butyrylcholinesterase, BChE) has been shown to be a clinically relevant biomarker in acute inflammatory diseases including burns.In this observational cohort study BChE activity was measured by using point-of-care testing (POCT), a novel method in acute burn care. POCT measurements were performed at emergency room admission (ERA) of 35 patients and repeated 12, 24 and 48 h later. All patients or their legal designees gave informed consent.Patients with burn injuries showed sustained BChE activity reduction following hospital admission. BChE activity correlated negatively with burn injury severity, organ failure severity and intensive care unit resource requirements. BChE activity measured at ERA and 12 h later identified survivors and predicted 28-day patient outcome with noninferior efficacy compared to the abbreviated burn severity index (ABSI) scoring. Finally, POCT-measured BChE activity might complement ABSI scoring and possibly improve early risk stratification in acute burn care therapy.