Chronic postoperative pain after non-intubated uniportal VATS lobectomy

Introduction

Patients undergoing thoracic surgery are at increased risk of developing, long-lasting pain. Beyond the non-surgical factors, the type of operation, including the number of incisions, and the anesthetic assessment seemed to be important factors, although some studies are controversial. The aim of our study was to examine the presence of chronic postoperative pain after non-intubated uniportal VATS lobectomy. We examined the difference between the intubated, relaxed and non-intubated spontaneous ventilation surgical approaches in patients who underwent video-assisted thoracoscopic (VATS) uniportal lobectomy.

Methods

Demographic and postoperative data were retrospectively collected and analyzed, focusing on the use of pain medications, in 67 patients of the 140 patients selected by propensity score matching who underwent intubated (iVATS) or non-intubated (NITS) uniportal VATS lobectomy. This study focused on the use of analgesic medications 3, 6, and 12 months after surgery.

Results

Thirty-five intubated and 32 non-intubated patients were compared. Although the analgesic consumption was nearly 2% higher among the iVATS patients during the follow-up period, there were no statistically significant differences at 3 months (15.6 vs. 17.1%) (p = 0.868), at 6 months (9.4 vs. 12.4%) (p = 0.785), and at 12 months (3.3 vs. 5.9%) (p = 0.633) between the NITS and iVATS groups, respectively. More female than male patients reported chronic pain, but the difference was not statistically significant (p = 0.616). Diabetes mellitus was a statistically significant cofactor associated with chronic pain (p = 0.03), while cardiac disease (p = 0.6), perioperative morbidity (p = 0.228), prolonged air leak (p = 0.057), and repeat drainage (p = 0.626) were not.

Conclusion

Our study suggests that after non-intubation VATS lobectomies, the postoperative pain was less at 3, 6, and 12 months in NITS patients compared to iVATS patients. The 2% difference was not significant, so it may not be appropriate to claim the advantages of NITS in terms of postoperative pain.

Spontaneous Ventilation Combined with Double-Lumen Tube Intubation during Thoracic Surgery: A New Anesthesiologic Method Based on 141 Cases over Three Years

BACKGROUND

Non-intubated thoracic surgery has not achieved widespread acceptance despite its potential to improve postoperative outcomes. To ensure airway safety, our institute has developed a technique combining spontaneous ventilation with double-lumen tube intubation (SVI). This study aimed to verify the feasibility and limitations of this SVI technique.

METHODS

For the SVI method, anesthesia induction involves fentanyl and propofol target-controlled infusion, with mivacurium administration. Bispectral index monitoring was used to ensure the optimal depth of anesthesia. Short-term muscle relaxation facilitated double-lumen tube intubation and early surgical steps. Chest opening preceded local infiltration, followed by a vagal nerve blockade to prevent the cough reflex and a paravertebral blockade for pain relief. Subsequently, the muscle relaxant was ceased. The patient underwent spontaneous breathing without coughing during surgical manipulation.

RESULTS

Between 10 March 2020 and 28 October 2022, 141 SVI surgeries were performed. Spontaneous respiration with positive end-expiratory pressure was sufficient in 65.96% (93/141) of cases, whereas 31.21% (44/141) required pressure support ventilation. Only 2.84% (4/141) of cases reversed to conventional anesthetic management, owing to technical or surgical difficulties. Results of the 141 cases: The mean maximal carbon dioxide pressure was 59.01 (34.4-92.9) mmHg, and the mean lowest oxygen saturation was 93.96% (81-100%). The mean one-lung, mechanical and spontaneous one-lung ventilation time was 74.88 (20-140), 17.55 (0-115) and 57.73 (0-130) min, respectively.

CONCLUSIONS

Spontaneous ventilation with double-lumen tube intubation is safe and feasible for thoracic surgery. The mechanical one-lung ventilation time was reduced by 76.5%, and the rate of anesthetic conversion to relaxation was low (2.8%).

[Changes of the T cell composition in the thymus during the COVID-19 pandemic]

INTRODUCTION

In our study, we aimed to investigate whether the COVID-19 infection itself or the vaccination against it affect the differentiation of T cells in the thymus, and whether the reduction in T cell counts observed in the blood of COVID-19-infected individuals is also observed at the tissue level in the thymus.

METHOD

Data from a total of 55 thymectomy patients were processed to create three groups: 1) the pre-COVID-19 (PC) group included 22 patients, 12 women and 10 men, who underwent thymectomy between 2008 and 2013; 2) in the no-COVID-19 (NC) group (patients without verified infection or vaccination), 20 patients, 11 women and 9 men, underwent thymectomy in 2020-2021; 3) the vaccinated or infected COVID-19 (VIC) group included 13 patients, 4 women and 9 men, who underwent thymectomy also in 2020-2021. The pathological samples were immunohistochemically tested for CD4, CD8, CD25 and FOXP3 to verify the helper, cytotoxic and regulatory T cells.

RESULTS

The VIC group had significantly lower values for CD4, compared to the PC and NC groups. The FOXP3 value was significantly lower in the VIC and NC groups compared to the PC group. No significant differences were found for CD8 and CD25 between the groups studied.

DISCUSSION

The COVID-19 infection or vaccination affects the T cell composition of the thymus. Decreased expression of CD4 has been demonstrated in the VIC group, which confirms a decrease in the T cell counts that also occurs in the thymus. The low FOXP3 levels observed in the NC group during the COVID-19 era, compared to the PC group, may be indicative of a high rate of asymptomatic coronavirus infections and a worsening of immunetolerance.

CONCLUSION

First in the world, we have verified that the helper T cell composition of the thymus in COVID-19 infection era is reduced, and in the asymptomatic patients the immune function is decreased as well. Orv Hetil. 2022; 163(52): 2062-2066.

The More Extensive the Spread through Air Spaces, the Worse the Prognosis Is: Semi-Quantitative Evaluation of Spread through Air Spaces in Pulmonary Adenocarcinomas

INTRODUCTION

The extent of spread through air spaces (STAS) is less investigated among patients with lung adenocarcinoma who underwent sublobar resection. Therefore, we aimed to evaluate the extent of STAS semi-quantitatively, to assess its prognostic impact on overall survival (OS) and recurrence-free survival (RFS), and to investigate the reproducibility of this assessment.

METHODS

The number of tumour cell clusters and single tumour cells within air spaces was recorded in three different most prominent areas (200x field of view). The extent of STAS was categorized into three groups, and the presence of free tumour cluster (FTC) was recorded.

RESULTS

Sixty-one patients were included. Recurrence was more frequent with higher grade (p = 0.003), presence of lymphovascular invasion (p = 0.027), and presence of STAS of any extent (p = 0.007). In multivariate analysis, presence of FTC (HR: 5.89; 95% CI: 1.63-21.26; p = 0.005) and more pronounced STAS (HR: 7.46; 95% CI: 1.60-34.6; p = 0.01) had adverse impact on OS and RFS, respectively. Concerning reproducibility, excellent agreement was found among STAS parameters (ICC range: 0.92-0.94).

DISCUSSION

More extensive STAS is an unfavourable prognostic factor in adenocarcinomas treated with sublobar resection. As the evaluation of extent of STAS is reproducible, further investigation is required to gather more evidence.

Anesthetic (r)evolution from the conventional concept to the minimally invasive techniques in thoracic surgery—narrative review

Background and Objective

Thanks to the growing experience with the non-intubated anesthetic and surgical techniques, most pulmonary resections can now be performed by using minimally invasive techniques. The conventional method, i.e., surgery on the intubated, ventilated patient under general anesthesia with one-lung ventilation (OLV) was considered necessary for the major thoracoscopic lung resections for all patients. An adequate analgesic approach (regional or epidural anesthesia) allows video-assisted thoracoscopy (VATS) to be performed in anesthetized patients and thus the potential adverse effects related to general anesthesia and mechanical OLV can be minimized.

Methods

Multiple medical literature databases (PubMed, Google Scholar, Scopus) were searched, using the terms [(non-intubated) OR (nonintubated) OR (tubeless) OR (awake)] AND [(thoracoscopic surgery)] from 2004 to December 2021. Thirty hundred and six scientific papers were collected. The editorials, commentaries, letters, and papers were excluded, that focus on other than the non-intubated (aka awake or tubeless) VATS technique, as well as the full text scientific papers available in languages other than English.

Key Content and Findings

After reviewing the literature, we identified “schools” with different techniques but with very similar results. Most of the differences were in the anesthetic technique, oxygenation and analgesia, however, the immunological results, and the qualitative parameters (inpatient hospital care days, complication rate, mortality) of the perioperative period showed great similarity, in addition, all three schools identified the same risk factors (hypoxia, hypercapnia, airway safety). The combination of spontaneous ventilation with double lumen tube intubation, called VATS-spontaneous ventilation with intubation (SVI) method seems to be suitable for reducing these risk factors, which may serve as an alternative for patients not suitable for the non-intubated technique in the near future.

Conclusions

Based on the results, non-intubated thoracic surgery appears to be an increasingly widespread, safe procedure, that will be available to a wider range of patients as experience expands and by the implication of the constantly evolving new processes.

A case study of acute oropharyngeal palsy concomitant with diabetic ketoacidosis

Acute oropharyngeal palsy is a rare variant of Guillain-Barré syndrome. In our study we present the case of a 63-year-old man with general symptoms who was diagnosed with diabetic ketoacidosis and prescribed insulin therapy. Two weeks later, the patient complained of paraesthesia of the perioral region and the tip of the tongue, dysphagia, and dysarthria. These symptoms were initially thought to be complications of the patient's type-1 diabetes. Due to rapidly developing paraparesis, the patient became bedridden. Clinical symptoms, cerebrospinal fluid analysis and a nerve conduction study resulted in a diagnosis of acute oropharyngeal palsy, a variant of Guillain-Barré syndrome. After five consecutive days of intravenous immunoglobulin treatment, neurological symptoms improved and the need for insulin ceased. One year later, the patient's only remaining neurological symptom was loss of tendon reflexes in the lower extremities. Furthermore, the patient's blood glucose level was normal without the use of medications or a special diet. Here, we report that oropharyngeal palsy can co-occur with diabetic ketoacidosis, and that immuntherapy is effective in treating both oropharyngeal palsy and type-1 diabetes. To our knowledge, this is the first description of a patient presenting with acut oropharyngeal palsy concomitant with diabetic ketoacidosis.

Near-infrared fluorescence guided surgery: State of the evidence from a health technology assessment perspective

Different applications of near-infrared fluorescence-guided surgery are very promising, and techniques that help surgeons in intraoperative guidance have been developed, thereby bridging the gap between preoperative imaging and intraoperative visualization and palpation. Thus, these techniques are advantageous in terms of being faster, safer, less invasive, and cheaper. There are a few fluorescent dyes available, but the most commonly used dye is indocyanine green. It can be used in its natural form, but different nanocapsulated and targeted modifications are possible, making this dye more stable and specific. A new active tumor-targeting strategy is the conjugation of indocyanine green nanoparticles with antibodies, making this dye targeted and highly selective to various tumor proteins. In this mini-review, we discuss the application of near-infrared fluorescence-guided techniques in thoracic surgery. During lung surgery, it can help find small, non-palpable, or additional tumor nodules, it is also useful for finding the sentinel lymph node and identifying the proper intersegmental plane for segmentectomies. Furthermore, it can help visualize the thoracic duct, smaller bullae of the lung, phrenic nerve, or pleural nodules. We summarize current applications and provide a framework for future applications and development.

[Early postoperative results of sublobal lung resections performed with spontaneous ventilation combined with double lumen tube intubation. A new surgical method]

Introduction. Non-intubated spontaneous ventilated (NITS) minimally invasive surgery (video-assisted thoracic surgery VATS) is a widespread procedure, but there are some doubts regarding its safety. We developed a safe method, spontaneous ventilation with intubation (SVI) to resolve these concerns. In this study, the early postoperative results of the SVI sublobar resections are presented. Methods. Between 2020 May 25 and 2021 March 26, 20 SVI VATS sublobar resection was performed with a double lumen intratracheal tube. Results. Surgeries were performed for 9 females and 11 males with a mean age of 66.1. The mean BMI was 27.8, FEV1 was 89.1%, and Carlson Comorbidity score was 6.1. The mean surgical time was 61.5 min, drainage time was 1.85 days and hospital stay was 3.35 days. Morbidity was found to be 5%. Primer lung cancer was removed in 9 cases, we performed 6 metastasectomies and in 5 cases benign lesion was removed. Conclusion. According to the early postoperative results spontaneous ventilated VATS sublobar resections with double lumen intratracheal tube can be considered a safe thoracic surgical method.

Perioperative Systemic Inflammation in Lung Cancer Surgery

Systemic inflammation (SI) is a response of the immune system to infectious or non-infectious injuries that defends the body homeostasis. Every surgical intervention triggers SI, the level of which depends on the extent of damage caused by the surgery. During the first few hours after the damage, the innate or natural immunity, involving neutrophils, macrophages, and natural killer cells, plays a main role in the defense mechanism, but thereafter the adaptive immune response ensues. The number of leukocytes is elevated, the levels of lymphocytes and natural killer cells are reduced, and the cytokines released after surgery correlate with surgical damage. Minimally invasive thoracic surgery procedures induce less inflammatory response and reduce the immune defense in patients to a more moderate level compared with the open surgery procedures; this immunosuppression can be further diminished in spontaneous ventilation cases. The normal functioning of the immune defense is important in controlling the perioperative circulatory tumor cells. Moreover, elevated levels of inflammatory cytokines before immune therapy have a negative impact on the response, and significantly shorten the progression-free survival. Clinically, the lower are the levels of cytokines released during lung surgery, the lesser is the postoperative morbidity, especially pneumonia and wound infection. The return to normal levels of lymphocytes and cytokines occurs faster after spontaneous ventilation surgery. The use of locoregional anesthesia can also reduce SI. Herein, we review the current knowledge on the effects of different operative factors on postoperative SI and defense mechanism in lung cancer surgery.

Pathophysiological Advantages of Spontaneous Ventilation

Surgical procedures cause stress, which can induce an inflammatory response and reduce immune function. Following video-assisted thoracoscopic surgery (VATS), non-intubated thoracic surgery (NITS) was developed to further reduce surgical stress in thoracic surgical procedures. This article reviews the pathophysiology of the NITS procedure and its potential for reducing the negative effects of mechanical one-lung ventilation (mOLV). In NITS with spontaneous ventilation, the negative side effects of mOLV are prevented or reduced, including volutrauma, biotrauma, systemic inflammatory immune responses, and compensatory anti-inflammatory immune responses. The pro-inflammatory and anti-inflammatory cytokines released from accumulated macrophages and neutrophils result in injury to the alveoli during mOLV. The inflammatory response is lower in NITS than in relaxed-surgery cases, causing a less-negative effect on immune function. The increase in leukocyte number and decrease in lymphocyte number are more moderate in NITS than in relaxed-surgery cases. The ventilation/perfusion match is better in spontaneous one-lung ventilation than in mOLV, resulting in better oxygenation and cardiac output. The direct effect of relaxant drugs on the acetylcholine receptors of macrophages can cause cytokine release, which is lower in NITS. The locoregional anesthesia in NITS is associated with a reduced cytokine release, contributing to a more physiological postoperative immune function.

Non-intubated Thoracoscopic Surgery-Tips and Tricks From Anesthesiological Aspects: A Mini Review

Background

In the last few decades, surgical techniques have been developed in thoracic surgery, and minimally invasive strategies such as multi-and uniportal video-assisted thoracic surgery (VATS) have become more favorable even for major pulmonary resections. With this surgical evolution, the aesthetic approach has also changed, and a paradigm shift has occurred. The traditional conception of general anesthesia, muscle relaxation, and intubation has been re-evaluated, and spontaneous breathing plays a central role in our practice by performing non-intubated thoracoscopic surgeries (NITS-VATS).

Methods

We performed a computerized search of the medical literature (PubMed, Google Scholar, Scopus) to identify relevant articles in non-intubated thoracoscopic surgery using the following terms [(non-intubated) OR (non-intubated) OR (awake) OR (tubeless) OR (regional anesthesia)] AND [(VATS) OR (NIVATS)], as well as their Medical Subject Headings (MeSH) terms.

Results

Based on the outcomes of the reviewed literature and our practice, it seems that pathophysiological concerns can be overcome by proper surgical and anesthetic management. All risks are compensated by the advantageous physiological changes that result in better patient outcomes. With the maintenance of spontaneous breathing, the incidence of potential adverse effects of mechanical ventilation, such as ventilator-induced lung injury and consequent postoperative pulmonary complications, can be reduced. The avoidance of muscle relaxants also results in the maintenance of contraction of the dependent hemidiaphragm and lower airway pressure levels, which may lead to better ventilation-perfusion matching. These techniques can be challenging for surgeons as well as for anesthetists; hence, a good knowledge of physiological and pathophysiological changes, clear inclusion and exclusion and intraoperative conversion criteria, and good communication between team members are essential.

Conclusion

NITS-VATS seems to be a feasible and safe method in selected patients with evolving importance as a part of the minimally invasive surgical and anesthetic conception and has a role in reducing perioperative complications, which is crucial in the thoracic surgical patient population.

Standard OSEM vs. regularized PET image reconstruction: qualitative and quantitative comparison using phantom data and various clinical radiopharmaceuticals

We investigated the block sequential regularized expectation maximization (BSREM) algorithm. ACR phantom measurements with different count statistics and 60 PET/CT research scans from the GE Discovery 600 and 690 scanners were reconstructed using BSREM and the standard-of-care OSEM algorithm. Hot concentration recovery and cold contrast recovery were measured from the phantom data. Two experienced nuclear medicine physicians reviewed the clinical images blindly. Liver SNR liver and SUV_max of the smallest lesion detected in each patient were also measured. The relationship between the maximum and mean hot concentration recovery remained monotonic below 1.5 maximum concentration recovery. The mean cold contrast recovery remained stable even for decreasing statistics with a highest absolute difference of 4% in air and 2% in bone for each reconstruction method. The D600 images resulted in an average 30% higher SNR than the D690 data for BSREM; there was no difference in SNR results between the two scanners with OSEM. The small lesion SUV_max values on the BSREM images with β of 250, 350 and 450, respectively were on average 80%, 60% and 43% (D690) and 42%, 29%, and 21% (D600) higher than in the case of OSEM. In conclusion, BSREM can outperform OSEM in terms of contrast recovery and organ uniformity over a range of PET tracers, but a task dependent regularization strength parameter (beta) selection may be necessary. To avoid image noise and artifacts, our results suggest that using higher beta values (at least 350) may be appropriate, especially if the data has low count statistics.

[Thrombolysis in case of ischemic stroke caused by aortic dissection]

Seldom, an acute aortic dissection can be the etiology of an acute ischemic stroke. The aortic dissection typically presents with severe chest pain, but in pain-free dissection, which ranges between 5-15% of the case, the neurological symptoms can obscure the sypmtos of the dissection. By the statistical data, there are 15-20 similar cases in Hungary in a year. In this study we present the case history of an acute ischemic stroke caused by aortic dissection, which is the first hungarian publication in this topic. A 59-year-old man was addmitted with right-gaze-deviation, acute left-sided weakness, left central facial palsy and dysarthric speech. An acute right side ischemic stroke was diagnosed by physical examination without syptoms of acute aortic dissection. Because, according to the protocol it was not contraindicated, a systemic intravenous thrombolysis was performed. The neurological sypmtoms disappeared and there were no complication or hypodensity on the brain computed tomography (CT). 36 hours after the thrombolysis, the patient become restlessness and hypoxic with back pain, without neurological abnormality. A chest CT was performed because of the suspition of the aortic dissection, and a Stanford-A type dissection was verified. After the acute aortic arch reconstruction the patient died, but there was no bleeding complication at the dissection site caused by the thrombolysis. This case report draws attention to the fact that aortic dissection can cause acute ischemic stroke. Although it is difficult to prove it retrospectively, we think the aortic dissection, without causing any symptoms or complain, had already been present before the stroke. In our opinion both the history of our patient and literature reviews confirms that in acute stroke the thrombolysis had no complication effect on the aortic dissection but ceased the neurological symptoms. If the dissection had been diagnosed before the thrombolysis, the aortic arch reconstruction would have been the first step of the treatment, without thrombolysis.

l-Arginine Pathway Metabolites Predict Need for Intra-operative Shunt During Carotid Endarterectomy

OBJECTIVE/BACKGROUND

Asymmetric dimethylarginine (ADMA) inhibits nitric oxide (NO) synthesis and is a marker of atherosclerosis. This study examined the correlation between pre-operative l-arginine and ADMA concentration during carotid endarterectomy (CEA), and jugular lactate indicating anaerobic cerebral metabolism, jugular S100B reflecting blood-brain barrier integrity, and with factors of surgical intervention.

METHODS

The concentration of l-arginine, ADMA, and symmetric dimethylarginine was measured in blood taken under regional anaesthesia from the radial artery of 55 patients prior to CEA. Blood gas parameters, concentration of lactate, and S100B were also serially measured in blood taken from both the radial artery and the jugular bulb before and after carotid clamping, and after release of the clamp. To estimate anaerobic metabolism, the jugulo-arterial ratio of CO₂ gap/oxygen extraction was calculated.

RESULTS

Positive correlation was found between pre-operative ADMA levels and the ratio of jugulo-arterial CO₂ gap/oxygen extraction during clamp and reperfusion (p = .005 and p = .01, respectively). An inverse correlation was found between the pre-operative l-arginine concentration and jugular lactate at each time point (both p = .002). The critical pre-operative level of l-arginine was determined by receiver operator curve analysis. If l-arginine was below the cutoff value of 35 μmol/L, jugular S100B concentration was higher 24 h post-operatively (p = .03), and jugular lactate levels were increased during reperfusion (p = .02). The median pre-operative concentration of l-arginine was lower in patients requiring an intra-operative shunt than in patients without need of shunt (median: 30.3 μmol/L [interquartile range 24.4-34.4 μmol/L] vs. 57.6 μmol/L [interquartile range 42.3-74.5 μmol/L]; p = .002).

CONCLUSION

High pre-operative ADMA concentration predicts poor cerebral perfusion indicated by elevated jugulo-arterial CO₂ gap/oxygen extraction. Low pre-operative l-arginine concentration predicts the need for a shunt. The inverse correlation between pre-operative l-arginine concentration and both jugular lactate and S100B during carotid clamping suggests a protective role of the NO donor l-arginine.

[In Process Citation]

OBJECTIVES

Different methods of open or minimally invasive thymectomies have been recommended for the treatment of myasthenia gravis (MG). We compared the results of standard transsternal thymectomy (TS) and two different types of minimally invasive thymectomies [video-assisted thoracoscopic extended thymectomy (VATET) and classic Video-Assisted Thoracoscopic Surgery (cVATS)] performed at the same department.

METHODS

During three different time periods 71 patients (60 female and 11 male; mean age 31 [range, 14-84] years) underwent thymectomy for MG. Twenty-three underwent standard transsternal thymectomy (January 1995 - September 2004), 22 VATET (September 2004 - August 2009), and 26 cVATS (September 2009 - December 2011) thymectomy for the right side. Operative data, MG- and surgery-related postoperative morbidity and early improvement of MG during the initial 1-year follow-up period were compared among the three methods.

RESULTS

There were no perioperative deaths during the study period. Operative time was 112, 211, and 116 minutes (p = 0.001) in the TS, VATET and cVATS, respectively, and the length of hospital stay was 8.9, 5.6, and 4.0 (p = 0.001) days. Postoperative MG-related neurological morbidity affected 21.7%, 18.2%, and 7.7% (p = 0.365) of the patients and the surgery-related morbidity rate was 4.3%, 13.7%, and 0% (p = 0.118) in the TS, VATET and cVATS groups, respectively. Symptom improvement rates were 91.3%, 94.7%, and 87.5% (p = 0.712), and complete remission rates were 13%, 10.5%, and 11.5% (p = 0.917) after TS, VATET and cVATS thymectomies, respectively.

CONCLUSIONS

In terms of operative time and hospital stay the best results were found after cVATS. The use of a less invasive surgical intervention resulted in less surgical-, and MG related neurological complications. The improvement of MG symptoms was excellent and results were similar after different types of thymectomies.

Cold wall effect eliminating method to determine the contrast recovery coefficient for small animal PET scanners using the NEMA NU-4 image quality phantom

The contrast recovery coefficients (CRC) were evaluated for five different small animal PET scanners: GE Explore Vista, Genisys4, MiniPET-2, nanoScan PC and Siemens Inveon. The NEMA NU-4 2008 performance test with the suggested image quality phantom (NU4IQ) does not allow the determination of the CRC values for the hot regions in the phantom. This drawback of NU4IQ phantom motivated us to develop a new method for this purpose. The method includes special acquisition and reconstruction protocols using the original phantom, and results in an artificially merged image enabling the evaluation of CRC values. An advantageous feature of this method is that it stops the cold wall effect from distorting the CRC calculation. Our suggested protocol results in a set of CRC values contributing to the characterization of small animal PET scanners. GATE simulations were also performed to validate the new method and verify the evaluated CRC values. We also demonstrated that the numerical values of this parameter depend on the actual object contrast of the hot region(s) and this mainly comes from the spillover effect. This effect was also studied while analysing the background activity level around the hot rods. We revealed that the calculated background mean values depended on the target contrast in a scanner specific manner. Performing the artificially merged imaging procedure and additional simulations using the micro hollow sphere (MHS) phantom geometry, we also proved that the inactive wall around the hot spheres can have a remarkable impact on the calculated CRC. In conclusion, we have shown that the proposed artificial merging procedure and the commonly used NU4IQ phantom prescribed by the NEMA NU-4 can easily deliver reliable CRC data otherwise unavailable for the NU4IQ phantom in the conventional protocol or the MHS phantom.

Have the boundaries of the 'grey zone' of perinatal resuscitation changed for extremely preterm infants over 20 years?

AIM

To determine the boundaries of the grey zone of discretionary resuscitation over the past 20 years.

BACKGROUND

As the likelihood of survival improves over time, the BW- and GA-specific boundaries of discretionary nonresuscitation should fall.

HYPOTHESIS

Between 1988 and 2008 reductions in BW- and GA-specific mortality would drive a parallel reduction in BW and GA boundaries of discretionary resuscitation.

METHODS

We determined the likelihood of resuscitation and survival to NICU discharge for all infants born <700 g or <26 gestational weeks from 1988 to 2008. In addition, for 1988, 1993, 1998, 2003 and 2008, we determined the BW and GA for the 10 smallest infants who were resuscitated, and the 10 largest infants who were not resuscitated. We excluded any infant born with congenital anomaly.

RESULTS

Mortality fell from 80% in 1988 to 28% in 2008, and as expected, the percentage who were resuscitated rose from 63% in 1988-93 to 95% in 2004-2008. However, unexpectedly, over the 20-year study period, the smallest infants who were resuscitated despite extreme immaturity did not change (450-550 g and 23-24 weeks) and the largest infants not resuscitated did not change (600-700 g and 23-24 weeks.

CONCLUSION

Neither the BW nor GA boundaries of the grey zone of discretionary resuscitation have fallen over the past 20 years. Factors guiding resuscitation at the border of viability are complex and incompletely understood.

Ischaemic postconditioning reduces serum and tubular TNF-α expression in ischaemic-reperfused kidney in healthy rats

OBJECTIVE

We studied the protective effects of postconditioning (PS) in healthy and hypercholesterolemic rats after renal ischaemia-reperfusion (IR) injury. We aimed to examine cytokine expression and apoptosis in tissue damage after revascularisation (TNF-α levels in serum and tissue).

METHODS

Male Wistar rats (n = 32) were divided into four groups. The animals of normal feed groups (NF) were fed with normal rat chow and the cholesterol feed groups (CF) were fed with 1.5% cholesterol containing diet for 8 weeks. Anaesthetized rats underwent a 45-min cross-clamping in both kidney pedicles. Ischaemia was followed by 120-min reperfusion with or without PS protocol (group PS vs. IR). Postconditioning was induced by four intermittent periods of ischaemia-reperfusion of 15-s duration each. Serum cholesterol, triglyceride, urea and creatinine levels were determined. Proinflammation was characterized by the measurement of serum TNF-α. Tissue injury in kidney was determined by formaline-fixed, paraffin-embedded tissue sections. Tissue TNF-α levels were determined by immunohistochemistry.

RESULTS

Significant elevation was observed in serum TNF-α level after IR injury in normal feed groups, which was reduced by PS. In CF group neither the elevation nor the postconditioning induced reduction were as significant as in the NF groups. In normal feed group PS caused a significant reduction in tissue TNF-α level which was significantly higher in CF.

CONCLUSIONS

Ischaemic postconditioning proved to be an effective defense against IR in NF groups, but it was ineffective in CF groups in kidney tissue.

End of life, death and dying in neonatal intensive care units in Latin America

AIM

Most analyses of end of life decisions in Neonatal Intensive Care Units (NICUs) have come from Europe/English-speaking countries. Would decisions be different in Latin American NICUs? Therefore, we aim to evaluate the approach to dying infants/families in NICUs in Latin America.

METHODS

Multinational descriptive study of all deaths in babies born at >22 weeks in eight NICUs in five Latin American countries. Deaths were categorized as: (i) no Cardiopulmonary Resuscitation (CPR) or life support offered; (ii) life support initiated but do not resuscitate (DNR) orders written or no CPR provided; (iii) full life support and CPR; and (iv) unclassifiable.

RESULTS

There were 100 deaths, 81% in >27 weeks. Seventeen infants received no CPR/life support at birth, 10 died in DR and seven in NICU. There were 27 infants in group 2, 54 in group three and two in group 4. No baby had care withdrawn or care withdrawn/CPR withheld. Thirty-two infants had 'do not resuscitate' order. Decisions without parents' involvement in 15%, both parents present at death 24% and sedatives/narcotics documented 14%.

CONCLUSIONS

Latin American NICUs differ from those in Northern Europe/English-speaking countries. More deaths are accompanied by full life support and CPR. DNR orders are rare. Withdrawal of life support is virtually non-existent. Latin American's doctors are more likely to make decisions without the objections of family about withholding life-sustaining treatment.

[Minimally invasive thymectomy with videothoracoscopy via the right chest]

BACKGROUND

The authors present the technique and results of minimally invasive thymectomy via the right chest based on their clinical practice.

PATIENTS AND METHODS

Between 1 June 2009 and 31 March 2011 27 patients (22 females, 5 males; mean age 35.1 [17-84] years) underwent thymectomy without sternotomy at the division of thoracic surgery of the Department of Surgery, University of Szeged. Indications were myasthenia gravis in 24 and thymoma in 3 patients. The incisions were the following: two 1.5 cm in the right breast fold and one 3 cm incisions in the axillara. There were no incisions in the neck or no sternotomy was carried out either. Preparation and removal of the thymus were performed by conventional and endoscopic instruments, and a drain was inserted into the right chest cavity up until the mediastinum.

RESULTS

Mean time for surgery was 119 minutes (45-285). There was no conversion and no transfusion needed. Further, there was no surgical mortality or morbidity detected. Mean time for chest drain removal was 2.05 (1-3) days, and mean length of hospital stay was 4.56 (4-7) days. Two patients were admitted to the intensive care unit for myasthenia symptoms. Importantly, myasthenia gravis improved in 91.6% of the patients.

CONCLUSIONS

Minimally invasive thymectomy is a safe procedure with excellent cosmetic results. Improvement in myasthenia gravis was similar to published literature data.

Preconditioning is a method that may reduce the negative side-effect of pneumoperitoneum

Increased intra-abdominal pressure during laparoscopy leads to hypoxia due to reduced blood flow. Aim of our study was to investigate whether preconditioning can reduce this negative effect of the pneumoperitoneum. Fifty female Wistar rats were used, divided into 5 groups. I: Sham operation (Sham), II: conventional pneumoperitoneum (PP), III: transvaginal pneumoperitoneum (TV), IV: preconditioning for 2.5 minutes in two cycles (Pre 2.5), V: preconditioning for 5 minutes (Pre 5). Malondialdehyde (MDA), reduced glutathione (GSH), sulfhydrylgroup (SH-) concentrations, superoxide-dismutase (SOD) and mieloperoxidase (MPO) activity, and anti-apoptotic pathway marker p-AKT level and inflammatory cytokine TNF-α were measured. SOD activity and GSH concentration were decreased in PP and TV groups comparing to Sham and preconditioning groups. MPO activity was decreased also in PP and TV groups comparing to the Sham group but in the preconditioning groups it has remained high. MDA concentration in plasma was increased in PP and TV groups comparing to Sham and preconditioning groups. There was no difference in the case of blood MDA and SH-concentrations between groups. Anti-apoptotic pathway marker p-AKT level was decreased in the TV group comparing to the sham and preconditioning groups. TNF-α level was increased in TV and preconditioning groups compared to the sham group. According to the results preconditioning can reduce negative effects of pneumoperitoneum.

Effect of vitamin E on reperfusion injuries during reconstructive vascular operations on lower limbs

INTRODUCTION

The challenge against reperfusion injury and tissue oxidative stress, especially in vascular surgical interventions has an essential importance to reach the optimal clinical result. Numerous experimental attempts have proved the positive antioxidant effect of vitamin E in both chronic and acute phase models. In our study we monitored the effect of continuous preoperative treatment with vitamin E, on oxidative stress and tissue inflammation reactions developed after reconstructive operations.

PATIENTS AND METHODS

32 patients have been involved in a randomized, prospective study, all suffering from AFS occlusion proved by angiography, and all undergone supragenual reconstruction. Duration of ischemia and amount of tissues under vascular clamping were almost the same in all patients. In the group treated with E-vitamin, we administered 1 x 200 mg of vitamin E p/o from the preoperative day till the 7th post operative day. Patients of the second group did not receive vitamin E.

MATERIALS AND METHODS

Peripheral blood samples were collected immediately before operation and at the end of the second reperfusion hour (early reperfusion period). Late reperfusion period has been monitored by analyzing blood samples taken at 24th hour and 7th day next to the operative ischemia. Among oxidative stress parameters, direct measurement of reactive oxygen intermediator (ROI) and determination of antioxidant state (GSH, Total-SH group, SOD) have been performed. Malondialdehyde was chosen as marker for lipidperoxidation. Inflammation reactions were monitored up on expression of adhesion molecules (CD11a and CD18). We also controlled the oscillation of myeloperoxidase (MPO) activity.

RESULTS

Our study has proved that preoperative (from the preoperative day till the 7th post operative day) administration of 200 mg vitamin E could reduce the level of oxidative stress developed after ischemic-reperfusion insult (lipidproxidation, antioxidant enzymes). According to our results, the prooxidant-antioxidant imbalance also diminished in the group with E-vitamin treatment. We proved that elective administration of vitamin E could decrease the WBC activity (MPO activity, free radicals production, expression of adhesion molecules) and its consequential local inflammation process, during early reperfusion.

Caregivers attitudes for very premature infants: what if they knew?

BACKGROUND

Decisions about resuscitation of extremely premature babies are controversial. Such decisions may reflect poor understanding of outcomes.

OBJECTIVE

To compare caregivers' attitudes towards the resuscitation of a premature infant if they are only told the infant's gestational age or if they are only given prognostic information for infants at that gestational age.

DESIGN/METHODS

Residents and nurses involved in perinatal care were asked whether they would resuscitate a depressed AGA 24-week gestation infant at birth. In another question they were asked whether they would resuscitate a depressed preterm infant with a 50% chance of survival, knowing that of those who survived, 50% would have a development 'within normal limits', 20-25% a serious handicap and 40% with behavioural and/or learning disability.

RESULTS

Two hundred and seventy-nine caregivers responded (91% response rate). In the scenario that only presented gestational age, 21% of respondents would resuscitate. In the scenario that only presented prognostic statistics, 51% of respondents would resuscitate (p<0.05).

CONCLUSIONS

Providers of perinatal health care respond to vignettes differently depending upon the format in which information is provided. The relative unwillingness to resuscitate a baby of 24-week gestation is surprising since outcomes for such babies are the same or better than those we described in the scenario that provided only outcome data without specifying gestational age. Two explanations are possible: (1) respondents have irrational negative associations with low gestational ages or (2) respondents are unaware of actual outcomes.

Reperfusion injury and inflammatory responses following acute lower limb revascularization surgery

After revascularization of an acute arterial occlusion the development of a serious ischaemic-reperfusion injury is a menacing challenge and a hard task in peripheral vascular surgery. A whale of evidences point to oxidative stress, as an important trigger, in the complex chain of events leading to reperfusion injury. In the present study authors aimed to examine oxidative stress parameters, antioxidant-prooxidant state and leukocyte adhesion molecules (CD11a and CD18) expression following acute revascularization surgery of lower limb.10 patients were examined in the prospective randomized study. Peripheral blood sample was collected in ischaemic period, and after reperfusion in the 2nd and 24th hours, and on 7th day. Superoxide-dismutase activity, reduced glutathion concentration and leukocytes free radical production were measured. The degree of lipidperoxidation was marked with the quantity of malondialdehyde. The expressions of adhesion molecules were measured with flowcytometry.The speed and rate of free radical production significantly increased in the early reperfusion (p<0.05). The level of antioxidant enzymes decreased after revascularization. The CD11a and CD18 expression of the granulocytes significantly (p<0.05) decreased right after the revascularization, but with a gradual elevation until the 7th day they exceed the ischaemic value. Our results showed a time specific turnover of the sensitive antioxidant-prooxidant balance after revascularization operation.

Ischaemic postconditioning reduces peroxide formation, cytokine expression and leukocyte activation in reperfusion injury after abdominal aortic surgery in rat model

OBJECTIVE

We studied the protective effects of ischaemic postconditioning (PS) on ischemia-reperfusion injury of the lower extremities in a rat model of abdominal aortic intervention. We aimed to examine the evoked oxidative stress, cytokine expression and leukocyte activation after revascularisation surgery.

METHODS

Anesthetized animals (48 Whistar rats) underwent a 60 min infrarenal aorta cross-clamping. After the ischaemic period, an intermittent 4 times 15 s reperfusion--15 seconds ischaemic episodes--were applied (ischaemic postconditioning: group PS). Then we started a 120 min reperfusion in the aorta. In untreated group animals underwent a long ischaemia (60 min) and the following reperfusion (group IR). Peripherial blood samples were collected before operation, and in early (5, 10, 15, 30, 60 and 120 min) reperfusion periods. Serum peroxide level, TNF-alpha concentration, myeloperoxidase (MPO) activity and PMA-induced leukocyte ROS production were measured.

RESULTS

In PS group, plasma peroxide level elevation was significantly lower in very early reperfusion (5-30 min) comparing to non-conditioned IR group (10.04+/-1.9 microM/l vs. 16.91+/-3.67 microM/l, p<0.05). PS also reduced serum TNF-alpha concentration (167.41+/-31.26 microg/ml vs. 116.55+/-12.04 microg/ml, p<0.05), MPO activity (1.759+/-0.239 microM/ml vs. 1.22+/-0.126 microM/ml, p<0.05) and leukocyte activation detected by PMA-induced leukocyte ROS production (5.7+/-0.96 AU/10(3) cells vs. 4.63+/-0.69 AU/10(3) cells).

CONCLUSIONS

Ischaemic postconditioning could reduce ROI production after IR in early reperfusion period, thus limiting ROI mediated tissue lesion, cytokine-leukocyte activation and inflammatory responses. PS seems to be an effective tool in vascular surgery to reduce reperfusion injuries after revascularization interventions.

Effect of cardiopulmonary bypass on cytokine network and myocardial cytokine production

BACKGROUND

In addition to the well-investigated proinflammatory cytokine expression, there is an ever increasing interest in the field of anti-inflammatory response to cardiopulmonary bypass (CPB). Evidence suggests that myocardium serves as an important source of cytokines during reperfusion and application of CPB. The effect of coronary artery bypass graft (CABG) without CPB on myocardial cytokine production has not as yet been investigated.

HYPOTHESIS

Cardiopulmonary bypass can cause long-term disturbance in pro- and anti-inflammatory cytokine balance, which may impede a patient's recovery following surgery. Therefore, the effect of CPB on the balance of the pro-/anti-inflammatory cytokines network and myocardial cytokine outflow was assessed throughout a longer period after surgery.

METHODS

Twenty patients were scheduled for CABG with CPB and 10 had off-pump surgery. Blood samples were taken before, during, and over the first week following surgery. Coronary sinus blood samples were collected during surgery. The ratio of pro- and anti-inflammatory cytokines was calculated and the cytokine concentration of peripheral and coronary sinus blood were compared in both groups.

RESULTS

Pro-/anti-inflammatory cytokine ratio decreased early after CPB followed by a delayed and marked increase. A more balanced ratio was present following off-pump surgery. Coronary sinus levels of certain cytokines exceeded the concentration of systemic blood in the course of CPB but not during off-pump operation.

CONCLUSION

Patients show pro-inflammatory predominant cytokine balance at a later stage after CPB in contrast to those without CPB. The heart produces a remarkable amount of cytokines only in the course of surgery with CPB.

Expression of CD97 and Adhesion Molecules on Circulating Leukocytes in Patients Undergoing Coronary Artery Bypass Surgery

OBJECTIVE

Leukocyte activation is thought to be responsible for the adverse effects and postoperative complications following cardiopulmonary bypass (CPB). A novel cell surface molecule, CD97, is a sensitive marker of leukocyte and primary lymphocyte activation. The present study aimed to determine the activation of different leukocyte subsets by comparing the expression of CD97 and adhesion molecules (CD11, CD18) in patients receiving coronary surgery with or without CPB.

METHODS

30 patients were enrolled and scheduled for coronary bypass surgery under CPB (20 patients, group A) and with off-pump (OP) operation (10 patients, group B). Blood samples were taken before and during surgery, and over the following first week.

RESULTS

Here, we report an early decrease in CD97 expression of granulocytes (PMN) and monocytes (MC) followed by an intensive increase reaching the maximum on postoperative days 2 and 3 in patients operated with CPB. The rate of active CD97-positive lymphocytes showed a marked, gradual increase until postoperative day 3 and remained elevated up to day 7 after CPB. OP surgery resulted in moderate alteration in the presence of CD97 on PMN, MC and lymphocytes. The expression of adhesion molecules was similar to CD97 in all leukocyte subsets.

CONCLUSION

The findings about CD97 expression suggest considerable leukocyte activation following coronary bypass with CPB compared to OP surgery. The collected data show that the lymphocytes are highly activated and involved in leukocyte sequestration after CPB. Moreover, the importance of CD97 in CPB-related inflammatory response can be stated.

A cost-effective screening method for pesticide residue analysis in fruits, vegetables, and cereal grains

This paper reports the results of studies performed to investigate the potential of applying thin layer chromatography (TLC) detection in combination with selected extraction and cleanup methods, for providing an alternative cost-effective analytical procedure for screening and confirmation of pesticide residues in plant commodities. The extraction was carried out with ethyl acetate and an on-line extraction method applying an acetone-dichloromethane mixture. The extracts were cleaned up with SX-3 gel, an adsorbent mixture of active carbon, magnesia, and diatomaceous earth, and on silica micro cartridges. The Rf values of 118 pesticides were tested in eleven elution systems with UV, and eight biotest methods and chemical detection reagents. Cabbage, green peas, orange, and tomatoes were selected as representative sample matrices for fruits and vegetables, while maize, rice, and wheat represented cereal grains. As an internal quality control measure, marker compounds were applied on each plate to verify the proper elution and detection conditions. The Rf values varied in the different elution systems. The best separation (widest Rf range) was achieved with silica gel (SG)--ethyl acetate (0.05-0.7), SG--benzene, (0.02-0.7) and reverse phase RP-18 F-254S layer with acetone: methanol: water/30:30:30 (v/v) (0.1-0.8). The relative standard deviation of Rf values (CV(Rf)) within laboratory reproducibility was generally less than 20%, except below 0.2 Rf, where the CVRf rapidly increased with decreasing Rf values. The fungi spore inhibition, chloroplast inhibition, and enzyme inhibition were found most suitable for detection of pesticides primarily for confirming their identity or screening for known substances. Their use for determination of pesticide residues in samples of unknown origin is not recommended.

Application of TLC for confirmation and screening of pesticide residues in fruits, vegetables, and cereal grains: Part 2. Repeatability and reproducibility of Rf and MDQ values

This paper illustrates the effect of major factors influencing the reproducibility of thin layer chromatography (TLC) separation and detection under largely differing environmental and laboratory conditions. The optimum conditions for reproducibility and detection sensitivity was obtained on 20 x 20 cm layer in the retention factor (Rf) range of 0.2-0.7 by applying the sample in spots of 3-4 mm diameter at 2 cm from the edge of the plate. The reproducibility rapidly decreased below Rf = 0.2. Above Rf = 0.2 the within-laboratory reproducibility of 219 pesticides obtained in ethyl acetate silica gel elution system by several laboratories was typically below 10%. The among-laboratories reproducibility of the average retention factors was generally below 12%. The minimum detectable quantities (MDQ) of 219 pesticide residues were determined with nine detection methods. The MDQ values largely varied depending on the mode of detection. Bioassay methods enabled the detection down to 0.1-10 ng, while 20-100 ng could be achieved with the chemical reagents. Higher MDQ values are also reported in order to assist the identification of compounds potentially present. The between-laboratories reproducibility of MDQ values was typically 1-5 MDQmin.

Dynamism of NF-κB and AP-1 Activation in the Signal Transduction of Ischaemic Myocardial Preconditioning

Nuclear factor (NF)-kappaB and activation protein (AP)-1 transcription factors play an important role in the signal transduction of delayed ischaemic preconditioning (PC) leading to myocardial cytoprotection. Because the exact mechanism of the activation of these factors is still not clear, we aimed to monitor the time fluctuation of NF-kappaB and AP-1 induction in an in vivo animal model. Furthermore, we measured the induction rate of these factors using repeated cycles of PC. Following median thoracotomy, anaesthetized animals (24 New Zealand White rabbits) were subjected to ischaemic PC by occlusion of the left anterior descending coronary artery for 5 min. After 10 and 30 min, and 1, 2, 3 and 4 h of reperfusion, tissue samples were taken from the ischaemic myocardium, and the DNA binding activity of the transcription factors was measured with electrophoretic mobility shift assay. A further 12 animals were subjected to 2 x, 3 x or 4 x 5-min ischaemic PC, and after a 30-min or 1-hour reperfusion period, we investigated the possible modulation of NF-kappaB and AP-1 induction. Our results show significant, biphasically increased NF-kappaB activity with peak levels at 30 min and 3 h of reperfusion in preconditioned myocardium. AP-1 increased monophasically, with the peak level at 1 h of reperfusion. Repeated PC stimuli enhanced the activity of both transcription factors analyzed, but there was no significant correlation between the number of cycles and the rate of activation. Our results show that the activation of NF-kappaB and AP-1 have a specific time curve, and the induction of these factors is only slightly influenced by the number of PC cycles.

The effect of different levels of peritoneal CO2 pressure on bleeding time of spleen capsule injury

AIMS

The authors, in contrast to similar injuries with open surgery, had observed spontaneous hemostasis of relatively large spleen capsule injuries during laparoscopic surgery.

METHODS

Standard spleen injuries were carried out in 5 anesthetized mongrel dogs at different CO2 pressures and in open surgery. Bleeding was checked every minute by wiping around the injury but not removing the clot. Bleeding time was measured until no more oozing was detected. At every pressure level 3-3 measurements were done and analyzed. Parenchymal pressure of the spleen and systemic blood pressure were detected with direct catheter implantation.

RESULTS

In open surgery the average bleeding time was 15.2 min; at 5, 15, and 25 mmHg CO2 pressures bleeding times were 12.3, 10.6, and 9.8 min, respectively. The parenchymal pressure of the spleen (5-6 mmHg) rose synchronously with peritoneal pressure, but no significant changes in systemic blood pressure were seen.

CONCLUSION

Peritoneal CO2 pressure may counterweight the parenchymal pressure of the spleen, thus helping hemostasis. There seems to be an inverse proportion between peritoneal pressure and bleeding time. In case of spleen capsule injury during laparoscopic surgery, chances for spontaneous hemostasis are much better compared to open surgery. Attention must be paid to maintain adequate peritoneal pressure.

Is peripheral blood a reliable indicator of acute oxidative stress following heart ischemia and reperfusion?

BACKGROUND

Reactive oxygen species (ROS) play a crucial role in membrane damage in ischemic-reperfusion syndromes. The aim of our work was to determine whether blood samples taken from a peripheral vein are a reliable indicator to reflect the development of oxidative stress following acute heart ischemia and reperfusion.

MATERIAL AND METHODS

In a dog model, the left descending coronary artery (LAD) was occluded for 60 min followed by 60 minutes of reperfusion. The lipid peroxidation marker malondialdehyde (MDA), endogenous antioxidants reduced glutathione (GSH), the activity of superoxide dismutase (SOD) enzyme and the stimulated radical production of isolated neutrophil granulocytes (PMN) were measured simultaneously from the peripheral vein and the coronary sinus before and at the end of the LAD occlusion, and again during reperfusion.

RESULTS

MDA and SOD values increased during reperfusion. At the end of 1 hour the reperfusion changes in the coronary sinus were significant (p<0.05). GSH increased in the femoral vein, but decreased in the coronary sinus. The radical-producing capacity of PMNs decreased by the end of LAD occlusion, and a further significant decrease was measured during reperfusion in the coronary sinus (p<0.01). In the peripheral venous blood samples the decrease of PMN radical production became significant only at 30 minutes of reperfusion (p<0.02), and the earlier difference between the coronary sinus and the femoral vein tended to level out following 60 minutes of reperfusion.

CONCLUSIONS

During early reperfusion following myocardial ischemia coronary sinus blood sampling gives an earlier indication of myocardial damage. At a later phase, peripheral blood samples may also be informative regarding the altered balance between ROS production and the antioxidant capacity.

[Thrombotic thrombocytopenic purpura and systemic lupus erythematous. Three cases presenting simultaneously]

Thrombotic thrombocytopenic purpura (TTP) is a clinical syndrome characterized by microangiopathic hemolytic anemia, thrombocytopenia, fever, neurological symptoms, and renal involvement. The relationship of TTP to systemic lupus erythematosus (SLE) has been recognized in the medical literature since 1939. The differential diagnosis is difficult because both diseases have similar clinical features. The mainstay for recognizing TTP in the context of active SLE is the presence of helmet red cells, marked reticulocytosis, and negative direct Coomb's test. We report three female patients with simultaneous presentation of TTP and SLE. We suggest combined treatment with immunosuppressive therapy and plasma exchange using fresh frozen plasma.

Epidemiology and ethics in the neonatal intensive care unit

There are many ethical dilemmas in the neonatal intensive care unit (NICU), and almost as many solutions as dilemmas. Religion, philosophy, natural law, civil law, criminal law, to name but a few, have each been invoked as a source of authority to resolve the inevitable conflicts arising at the confluence of uncertain outcome, physical pain, and financial expenditure. This article takes a different approach. Here we begin by envisioning what we would most like to know about NICU care that we do not currently know (or at least is not widely known), and then combine "thought experiments" with preliminary "real experiments" to acquire a hypothetical database from which ethics in the NICU can be informed.

The physician as a health care proxy

Many states prohibit patients from appointing their physicians as health care proxies, fearing paternalism and conflict of interest. But the potential for conflict is not unique to physicians, and patients may have compelling reasons to prefer that their doctor make decisions on their behalf. Managing potential conflicts serves patients better than denying them the right to choose who will make health care decisions for them when they are no longer competent.