Propofol-induced hippocampal Neurotoxicity: A mitochondrial perspective

Propofol is a frequently used anesthetic. It can induce neurodegeneration and inhibit neurogenesis in the hippocampus. This effect may be temporary. It can, however, become permanent in vulnerable populations, such as the elderly, who are more susceptible to Alzheimer's disease, and neonates and children, whose brains are still developing and require neurogenesis. Current clinical practice strategies have failed to provide an effective solution to this problem. In addition, the molecular mechanism of this toxicity is not fully understood. Recent advances in molecular research have revealed that apoptosis, in close association with mitochondria, is a crucial mechanism through which propofol contributes to hippocampal toxicity. Preventing the toxicity of propofol on the hippocampus has shown promise in in-vivo, in-vitro, and to a lesser extent human studies. This study seeks to provide a comprehensive literature review of the effects of propofol toxicity on the hippocampus via mitochondria and to suggest translational suggestions based on these molecular results.

Effect of Desmopressin on Bleeding After Heart Surgeries: A Narrative Review

Desmopressin is an analog of the antidiuretic hormone (vasopressin), which causes anticoagulant activity by increasing plasma factor 8. The use of desmopressin dates back to 1977, when this hormone was used to prevent bleeding during tooth extraction and surgery in patients with hemophilia A and von Willebrand disease. After that, this hormone was expanded to prevent bleeding in congenital defects and conditions such as chronic kidney and liver failure. Also, this hormone is used to prevent bleeding in major surgeries such as heart surgery, where the patient loses much blood and needs a blood transfusion. Considering the importance of desmopressin in bleeding control, the present study was conducted to investigate the possible effect of this hormone in heart surgery.

Effect of Vitamin C Infusion on Cerebral Oximetry During General Anesthesia for Carotid Endarterectomy in Diabetic Patients

Background

There is conflicting information about the effect of vitamin C on brain oxygenation during anesthesia.

Objectives

The current study was designed and performed to assess the effect of vitamin C infusion and brain oxygenation with cerebral oximetry on improving brain perfusion during general anesthesia in vascular surgery of diabetic patients.

Methods

This randomized clinical trial was performed on patients candidates for endarterectomy under general anesthesia and referred to Taleghani Hospital in Tehran, Iran, during 2019 - 2020. Considering inclusion criteria, the patients were divided into placebo and intervention groups. The patients in the placebo group received 500 mL of isotonic saline. In the intervention group, the patients received 1 g of vitamin C diluted in 500 mL of isotonic saline by infusion half an hour before anesthesia induction. Patients' oxygen levels were continuously measured by a cerebral oximetry sensor. The patients were put in a supine position for 10 minutes before and after anesthesia. At the end of the surgery, the indicators considered in the study were evaluated.

Results

No considerable difference was observed between systolic and diastolic blood pressure, heart rate, mean arterial pressure, partial pressure of carbon dioxide, oxygen saturation, regional oxygen saturation, supercritical carbon dioxide, and end-tidal carbon dioxide in total and between the two groups in the three stages before and after anesthesia induction and at the end of surgery (P > 0.05). Additionally, there was no significant difference between blood sugar (BS) levels in the study groups (P > 0.05) but in BS levels at three stages before and after anesthesia induction and at the end of the surgery, with a significant difference (P < 0.05).

Conclusions

The amount of perfusion in the two groups and, therefore, in total at the three stages before and after anesthesia induction and at the end of surgery is not different.

Effects of Acute Potassium Chloride Administration on Ventricular Dysrhythmias after Myocardial Infarction in a Rat Model of Ischemia/Reperfusion

Background: Acute myocardial infarction is an important cause of morbidity. This study aimed to investigate the effects of the administration of potassium chloride (KCl) on reperfusion-induced injuries in a rat model of myocardial ischemia/reperfusion. Methods: Thirty-six male Wistar rats, weighing 200 to 250 g, were randomly assigned to 3 experimental groups: control, K1 (10 µg/kg of KCl), and K2 (20 µg/kg of KCl). Twenty minutes before ischemia, a single dose of 10 and 20 µg/kg of KCl was intraperitoneally administered in the K1 and K2 groups, respectively. The coronary artery was occluded for 30 minutes (ischemia); thereafter, it was opened for 60 minutes (reperfusion) to measure hemodynamic parameters and ventricular arrhythmias. Blood sampling was performed after the reperfusion period to determine the serum levels of lactate dehydrogenase, troponin I, creatine kinase (CK)-MB, malondialdehyde, and pro-oxidant-antioxidant balance. Results: Serological parameters significantly decreased in the potassium groups compared with the control group. In particular, the decline was more pronounced for the serum levels of lactate dehydrogenase (1180.25±69.48 vs 1556.67±77.02 U/L; P=0.011), troponin I (21.98±0.61 vs 28.76±1.65 ng/mL; P=0.020), and pro-oxidant-antioxidant balance (15.51±0.72 vs 20.63±1.42 HK; P=0.041) in the K2 group compared with the K1 group. Moreover, the administration of 20 µg/kg of KCl significantly decreased the incidence of ventricular tachycardias and fibrillations compared with the control group (P=0.002). Additionally, no considerable differences were observed between the control group and the groups with 10 µg/kg and 20 µg/kg of KCl regarding the number of ventricular ectopic beats.  Conclusion: The administration of KCl before ischemia could reduce ventricular arrhythmias and reperfusion-induced injuries by reducing oxidative stress.

Introducing and Prospective Efficacy Comparison of an Innovative and Affordable Technique for the Treatment of Distal Radius Fractures

Background

There are different treatments as well as controversies surrounding the adequate treatment for Distal Radius Fractures (DRF). In the absence of enough evidence[HYPHEN]base data regarding clinical effectiveness of available treatments, cost should be considered as an essential factor in selecting the surgical technique for DRF treatment. The goal of this study is introducing an improved and modified pin[HYPHEN]and[HYPHEN]plaster (MP&P) technique as an affordable alternative for treatment of DRF. This study also assesses and compares the outcomes of DRF treatment by using the introduced method versus external fixation (EF) technique.

Methods

In this clinical cohort study, 98 patients presenting with closed DRF Types III or IV, randomly were classified into two modified P&P (50 patients) and EF (48 patients) groups and assessed for functional, clinical, radiographic and overall outcome at the time, 2, 10 and 22 months after surgery. They were also followed[HYPHEN]up for up to 3 years to determine the rate of complications.

Results

Eighty one percent of EF and 86% of MP&P group were female. The average ages in the EF and MP&P groups were 44.9 ± 12.4 and 46.1 ± 5.4, respectively. Around 70% of the patients in each group had a Type III fracture, and 30% had Type IV. The rate of complications was higher among EF group patients (seven major and seven minor complications) compared to the MP&P (only 4 minor complications), however the difference between two groups regarding the complications and treatment outcome were insignificant, except in extension ROM and the quick[HYPHEN]dash score (only in two and four months follow up visits) and also returning to work (only in two month follow up visit).

Conclusion

This study introduces a modified P&P technique that protects the transverse palmar curvature, prevents the collapse of the distal radius, and simplifies casting, thereby obviating a full arm cast and mitigating elbow stiffness in patient outcomes. This modified technique could be considered as a more cost[HYPHEN]conscious alternative to external fixation for patients with distal radius fractures.

Complicated Congenital Dislocation of the Knee: A Case Report

Congenital dislocation of the knee (CDK) is a rare disorder. We report the case of a 7-year-old girl with bilateral knee stiffness, marked anterior bowing of both legs, and inability to walk without aid. Radiologic investigation revealed bilateral knee joint dislocation accompanied by severe anterior bowing of both tibia proximally and posterior bowing of both femur distally, demonstrating a complicated congenital knee dislocation. Two-staged open reduction with proximal tibial osteotomy was performed to align the reduced knee joints. The patient was completely independent in her daily activities after surgical correction.

A new method for tibial torsion measurement by computerized tomography

BACKGROUND

Computerized tomography (CT) is the gold standard technique for tibial torsion assessment. This study compared two methods of tibial torsion assessment and proposed a new method, which could be of value in cases of abnormal fibular changes.

METHODS

The CT-scanograms of 60 participants were assessed by using two different techniques, differed in determination of the distal tibial axis.

RESULTS

The interobserver reliability was 0.861 and 0.863 in the first and second methods, respectively. The intraobserver reliability in both measurement methods was 0.868.

CONCLUSIONS

We proposed a reliable method, independent of the fibular midpoint, in assessment of tibial torsion by CT.

Patellar tendon donor-site healing during six and twelve months after Anterior Cruciate Ligament Reconstruction

BACKGROUND

Bone-Patellar Tendon-Bone Graft is one of the most acceptable methods of treatment for Anterior Cruciate Ligament rupture (ACL). This study evaluates the recovery process of the graft donor site.

METHODS

This study evaluates the graft donor site recovery in 23 patients with ACL reconstruction, 6 and 12 months after the patellar tendon graft surgery.

RESULTS

In 70 percent of the cases, the healing process was completed after 6 months and the remaining 30 percent recovered after 12 months.

CONCLUSION

Time is an important factor in the recovery process of the patellar tendon for reconstruction of the ACL.

Comparison of different methods of femoral fixation anterior cruciate ligament reconstruction

The aim of this study is to compare three modes of femoral fixation, namely Aperfix, Rigidfix and Endobutton, in anterior cruciate ligament (ACL) reconstruction. 120 patients were randomly assigned to three groups, each consisting of 40 patients, and each group was treated by one of the above mentioned methods of femoral fixation. All patients were examined prior to and 24 months after surgery, and they were compared for anterior tibial displacement using the Lysholm score and KT-1000. The three modes of femoral fixation were not significantly different in terms of time of surgery. In the Endobutton group, the Lysholm score rose from 63.21±18.59 prior to ACL reconstruction to 90.64±9.47 after the surgery, while it rose from 65.72±18.74 to 96.22±5.35 in the Aperfix group and from 69.21±17.45 to 90.64±9.47 in the Rigidfix group. Anterior tibial displacement was 3.96±1.58 mm for Endobutton, 4.28±1.48 mm for Rigidfix and 4.03±1.79 mm for Aperfix. Aperfix was indicated to yield a better outcome in terms of instant stability and general results.

Adult tibial shaft fractures - different patterns, various treatments and complications

Background

Tibial Fractures constitute a large number of emergency operations in most trauma centers. There are different approaches for tibial fractures. To our knowledge, there is insufficient evidence to consider post-operative complications in relation to both surgical methods and the types of fractures. Our purpose is to report our experience regarding the efficacy and complications associated with diverse surgical methods of different patterns of tibial shaft fractures in adults.

Material/Methods

We studied 387 adult patients. The patients’ information was registered from the charts and after examination. The methods used were intramedullary interlocking nails, simple intramedullary rods, plating and external fixation. Early and late complications were recorded and by applying the DELPHI method different treatments were compared. Finally, the safest mode of treatment is proposed.

Results

In the intramedullary interlocking nails method the most noticeable complication was delayed union and the highest rate of complications was seen in open oblique fractures. In the simple intramedullary rods method the most frequent complication was pain, and in the with butterfly fractures the complications were the most. In the plating method the most frequent complication was pain, and most of the complications were seen in open comminuted fractures. Finally, in the external fixation method the most frequent complication was non-union and complications were the highest in the patients with oblique, comminuted and segmented fractures.

Conclusions

The proposed method to treat transverse, oblique and butterfly fractures is simple intramedullary rods; whereas intramedullary interlocking nails is the better method for comminuted, segmented and spiral fractures.

Avascular necrosis of the femoral head in children with acute lymphoblastic leukemia: a 4- to 9-year follow-up study

Avascular necrosis of the femoral head is usually seen in children aged 1.5 to 10 years, reaching a peak incidence between the ages of 4 and 9. Avascular necrosis of the femoral head is a known complication of corticosteroid therapy in acute lymphoblastic leukemia. There are few reports in the literature regarding the natural history of this condition, and there is no consensus on its management. This study examined the natural history of avascular necrosis of the femoral head in children with leukemia. From 1993 to 2006, a total of 865 children with acute lymphoblastic leukemia were admitted to the hematology-oncology ward of a children's hospital. The diagnosis of acute lymphoblastic leukemia was established by bone marrow aspiration. Based on clinical and radiographic findings, avascular necrosis of the femoral head was found in 7 patients; these patients underwent follow-up for 4 to 9 years. Avascular necrosis of the femoral head was clinically symptomatic in all of the children, and they had advanced radiographic collapse of the femoral head. However, the head of the femur was not at risk in any patient based on clinical and radiographic findings. Patients received supportive treatment such as abduction brace and physiotherapy. After 4 to 9 years of follow-up, clinical and radiographic results were satisfactory. Provided that the head of the femur is not at risk, avascular necrosis of the femoral head in children with acute lymphoblastic leukemia may be successfully managed with nonoperative care.

Total hip arthroplasty in advanced osteonecrosis: the short-term results by metal-on-metal hip resurfacing

BACKGROUND

Characteristically, osteonecrosis affects younger patients who typically refer to the orthopedic surgeon for the first time in the third to fifth decades of life, in the late stages of the disease. Femoral metal-on-metal hip resurfacing is as an alternative to conventional total hip arthroplasty in treating osteoarthritis of the hip. Since there are already many reports regarding the successful outcome of resurfacing in advanced osteoarthritis, the purpose of this study was to analyze the clinical outcomes of this procedure in patients with osteonecrosis of the femoral head and to compare them with a matched group of patients with osteoarthritis.

MATERIAL/METHODS

This retrospective cohort study evaluated a consecutive series of 52 patients with end-stage osteonecrosis (28 patients) and osteoarthritis (24 patients) of the femoral head, managed by metal-on-metal hip resurfacing in a referral orthopedic center from Feb 2002 to May 2007. Pain, function and deformity were evaluated with the use of the Harris hip score after the operation. Patients were clinically followed for a mean of 41 months.

RESULTS

The patients in the osteoarthritis group had a significantly higher mean age than those in the osteonecrosis group (47.88 ± 12.6 vs 30.86 ± 7.5, p=0.003). The clinical outcomes were similar for both groups. There was no significant difference in mean Harris hip score (p=0.347) and hip joint range of motion (p=0.346) between osteonecrosis and osteoarthritis groups after surgery.

CONCLUSIONS

On the basis of these initial findings, we recommend MOM resurfacing as a viable treatment option for patients with advanced stages of osteonecrosis.

Comparison of drain clamp after bilateral total knee arthroplasty

Suction drains provide an easy and feasible method for controlling hemorrhage after total knee arthroplasty. However, there has been no compromise regarding the optimum clamping time for these drains. We conducted a randomized clinical trial in 50 patients to compare 12-hour drain clamping and continuous drainage after total knee arthroplasty in terms of wound complications, blood loss, and articular arc of motion. To eliminate any other factor except duration of clamping, we chose to compare only knees belonging to a single patient and to restrict the study to those knees undergoing surgery due to osteoarthritis. From a total of 100 knees (50 patients) studied, the 12-hour-clamping method resulted in a significantly smaller amount of postoperative blood loss (p < 0.001). The passive ranges of motion and wound complications were not significantly different between the two groups.

Congenital bony fusion (absence) of the knee: a case report

Congenital knee ankylosis is a rare condition which might be accompanied with other abnormalities or not. To our knowledge, there is no report on true bony ankylosis of the knee. The only ones in the literature include fibrous knee ankylosis. Thus this seems to be the first presentation of true congenital bony fusion of the knee joint.

Clinical results of reversed V-shaped high tibial corticotomy with minimally invasive surgery without internal fixation devices

High tibial osteotomy is a method of treating knee osteoarthritis due to genu varum in advanced stages. High tibial osteotomy-associated problems continue to be reported. The purpose of this study was to investigate the clinical results of a new, innovative method of high tibial osteotomy with 3- to 13-year follow-up. Between 1996 and 2006, our new surgical method was performed on 293 patients with medial compartment osteoarthritis and genu varum. All patients were examined preoperatively, 6 months postoperatively, and at final follow-up. The Hospital for Special Surgery Knee Scoring System (HSS) was used at final follow-up, and limb alignment and patient satisfaction were reassessed. Immediate postoperative complications included varus recurrence, knee instability, and peroneal nerve palsy, and no signs of tibial nonunion or infection were observed. At final follow-up, 3 cases of genu recurvatum, 2 cases of peroneal nerve palsy, and 25 cases of loss of correction were observed. Average postoperative HSS score was 85 (range, 47-97), and 97.8% of the patients were satisfied. This new method is a good alternative for the correction of genu varum because it requires a small incision, is soft tissue friendly, is a corticotomy instead of an osteotomy, requires no internal or external fixation devices, has a shorter duration and an acceptable complication and recurrence rate, and results in satisfactory HSS scores and higher patient satisfaction rates.

Epidemiology of adult tibial shaft fractures: a 7-year study in a major referral orthopedic center in Iran

BACKGROUND

Epidemiologic differences among various fracture sites and within different populations are important as they imply different cultures and lifestyles in each region. One of these fractures is the tibial shaft fracture. Rather few epidemiological studies have been undertaken on this injury. This study was designed to provide an update on various aspects of tibial shaft fractures during 1999-2006 in a referral educational orthopedic center in Iran.

MATERIAL/METHODS

The charts of 854 adult patients were evaluated in a cross-sectional study. All the patients were examined and the results were registered. The collated information was classified along with descriptive statistical analysis.

RESULTS

The highest frequency of these fractures was seen in the 20-30 year age group in both genders, and women had a higher rate than men in people aged > or =50 years old. The most common cause of fractures was road traffic accidents; 54% of all injuries were closed fractures and 46% were open. The most frequent fracture pattern was comminuted and the fewest were segmented and with butterfly fractures. The most noticeable complication early after treatment was infection and those during at least one year follow-up were pain, nonunion, and delayed union.

CONCLUSIONS

The peak frequency of tibial shaft fractures in Iran was one decade higher than in European populations and in those > or =50 years old the rate was higher in women, which was two decades lower than the mentioned populations. Furthermore, in this study in addition to high-energy trauma, low-energy trauma also had a great role.

Repeated administrations of dopamine receptor agents affect lithium-induced state-dependent learning in mice

The influence of repeated administration of dopamine receptor agents on the effect of lithium on lithium-induced state-dependent learning was examined in mice. Immediate post-training intraperitoneal (i.p.) administrations of lithium (10 and 20 m/kg) decreased the step-down latency of a single-trial inhibitory avoidance task. This was fully or partly reversed by pre-test administration of the same doses of the drug, with maximum response at the dose of 10 mg/kg, suggesting state-dependent learning was induced by lithium. Here, it has also been shown that repeated intracerebroventricular administrations of a mixed D1/D2 dopamine receptors agonist apomorphine (once daily injections of 0.5 microg/mouse for three consecutive days followed by five days of no drug treatment) increased the effect of lower doses of pre-test lithium (1.25, 2.5 and 5 mg/kg, i.p.) on the reinstatement of the step-down latency decreased by post-training lithium (10 mg/kg). On the contrary, not only repeated administrations of the dopamine D1 receptor antagonist SCH 23390 (0.5 and 1 microg/mouse) but also the dopamine D2 receptor antagonist sulpiride (0.3 and 1 microg/mouse) disrupted the state-dependent learning induced by lithium. These results suggest that state-dependent learning induced by lithium may be altered by repeated pretreatment of dopamine receptor agents.

Local control of soft tissue sarcoma of the extremity: the experience of a multidisciplinary sarcoma group with definitive surgery and radiotherapy

Data gathered on 62 patients with soft tissue sarcoma of an extremity, treated in entirety by an experienced multidisciplinary sarcoma group, were analysed. With a philosophy of emphasising attainment of histologically negative margins at carefully planned limb sparing surgery, combined with either pre-operative or postoperative radiation therapy, a crude local control rate of 95% (59 of 62 patients) at a minimum of 24 months follow-up was obtained. Of 9 patients with microscopically positive margins after definitive surgery, 8 had undergone maximal resection compatible with preservation of function. One of these 9 failed locally, indicating that radiation therapy is effective in eradicating microscopic disease in this tumour. The excellent local control obtained with limb-sparing surgery in this series justifies early referral of patients with these uncommon cancers to an experienced multidisciplinary unit. 26 patients (42%) failed systemically at a minimum of 24 months follow-up, and 19 (30.6%) died of their disease, confirming the need for effective systemic therapy in soft tissue sarcoma. Tumours greater than 10 cm in diameter had a greater risk of systemic relapse.