Perioperative factors influencing the mortalit

WSTĘP: Tętniaki aorty brzusznej są uznaną przyczyną zwiększonej śmiertelności w populacji europejskiej. Dlatego ważna jest identyfikacja śródoperacyjnych czynników ryzyka zgonu w okresie okołooperacyjnym. MATERIAŁ I METODY: Prospektywnym badaniem obserwacyjnym, przeprowadzonym w Klinice Chirurgii Naczyniowej Pomorskiego Uniwersytetu Medycznego w Szczecinie, objęto grupę 95 pacjentów z tętniakiem aorty brzusznej w odcinku podnerkowym. Na podstawie kryteriów TASC pacjentów zakwalifikowano do implantacji protezy naczyniowej. Analizowano wpływ czynników hemodynamicznych i metabolicznych na śmiertelność okołooperacyjną. Obserwację badanej populacji prowadzono przez 28 dni. WYNIKI: Wykazano, że wzrost stężenia mleczanów, potasu oraz spadek wartości pH szczególnie w pierwszych minutach po odklemowaniu aorty były zasadniczymi czynnikami zwiększającymi śmiertelność w okresie okołooperacyjnym. Ponadto ryzyko zgonu było zwiększone, jeśli poza znieczuleniem ogólnym nie zastosowano znieczulenia regionalnego. Poza tym nie wykazano istotnego wpływu pozostałych badanych czynników. WNIOSKI: Zastosowanie znieczulenia zewnątrzoponowego u pacjentów poddawanych operacjom tętniaków aorty brzusznej jest istotnym, niezależnym czynnikiem zmniejszającym śmiertelność we wczesnym okresie pooperacyjnym. Natomiast zmniejszenie wartości pH, wzrost stężenia potasu i mleczanów w pierwszych minutach po odklemowaniu aorty może być przydatnym wskaźnikiem służącym do identyfikacji pacjentów zagrożonych zwiększonym ryzykiem zgonu we wczesnym okresie pooperacyjnym.INTRODUCTION: Abdominal aorta aneurysm is a recognized cause of death for the European population. The identification of intra-operative risk factors for perioperative death is of crucial importance for the society. MATERIAL AND METHODS: A prospective observational study was conducted in the Vascular Surgery Department of the Pomeranian Medical University in Szczecin, Poland. The study group consisted of 95 patients, diagnosed with abdominal aorta aneurysm in the sub-renal region scheduled for an operative procedure of straight vascular graft implantation. Patient qualification was fulfilled according to TASC criteria. The influence of preoperative factors, hemodynamic and metabolic parameters on the risk of death in the study population was analyzed. Postoperatively, observation was continued for 28 days. RESULTS: In this study group an increase of lactate, potassium levels or pH decrease during the first minute post cross-clamp release were significant risk factors for perioperative death. The importance of metabolic parameters is a recognized risk factor, however their statistical significance within the first minute post cross-clamp release is in our opinion of crucial importance. Additionally, significantly higher mortality was reported among patients without epidural anaesthesia. No importance of other analyzed parameters was found. CONCLUSIONS: Epidural anaesthesia is an independent factor decreasing mortality in the early postoperative period in patients undergoing abdominal aorta aneurysm repair. A decrease of pH value and increase of lactate and K+ levels within the first minute after aortic cross-clamp release may be a valuable tool in identifying patients with an increased risk of perioperative death after abdominal aorta prosthesis implantation

Możliwości wykonania próby bezdechu w czasie procedury rozpoznawania śmierci mózgu u chorych leczonych z użyciem utlenowania pozaustrojowego (ECMO)

Extracorporeal Membrane Oxygenation (ECMO) is a well-established method of support in patients with severe respiratory and/or circulatory failure. Unfortunately, this invasive method of treatment is associated with a high risk of neurological complications including brain death. Proper diagnosis of brain death is crucial for the termination of futile medical care. Currently, the legal system in Poland does not provide an accepted protocol for apnea tests for patients on ECMO support. Veno-arterial ECMO is particularly problematic in this regard because it provides both gas exchange and circulatory support. CO2 elimination by ECMO prevents hypercapnia, which is required to perform an apnea test. Several authors have described a safe apnea test procedure in patients on ECMO. Maximal reduction of the sweep gas flow to the oxygenator should maintain an acceptable haemoglobin oxygenation level and reduce elimination of carbon dioxide. Hypercapnia achieved via this method should allow an apnea test to be conducted in the typical manner. In the case of profound desaturation and an inadequate increase in the arterial CO2 concentration, the sweep gas flow rate may be increased to obtain the desired oxygenation level, and exogenous carbon dioxide may be added to achieve a target carbon dioxide level. Incorporation of an apnea test for ECMO patients is planned in the next edition of the Polish guidelines on the determination of brain death.Extracorporeal Membrane Oxygenation (ECMO) is a well-established method of support in patients with severe respiratory and/or circulatory failure. Unfortunately, this invasive method of treatment is associated with a high risk of neurological complications including brain death. Proper diagnosis of brain death is crucial for the termination of futile medical care. Currently, the legal system in Poland does not provide an accepted protocol for apnea tests for patients on ECMO support. Veno-arterial ECMO is particularly problematic in this regard because it provides both gas exchange and circulatory support. CO2 elimination by ECMO prevents hypercapnia, which is required to perform an apnea test. Several authors have described a safe apnea test procedure in patients on ECMO. Maximal reduction of the sweep gas flow to the oxygenator should maintain an acceptable haemoglobin oxygenation level and reduce elimination of carbon dioxide. Hypercapnia achieved via this method should allow an apnea test to be conducted in the typical manner. In the case of profound desaturation and an inadequate increase in the arterial CO2 concentration, the sweep gas flow rate may be increased to obtain the desired oxygenation level, and exogenous carbon dioxide may be added to achieve a target carbon dioxide level. Incorporation of an apnea test for ECMO patients is planned in the next edition of the Polish guidelines on the determination of brain death

Remifentanil for labour pain relief

Labour is thought to be one of the most intense and painful experiences in a woman’s life. Numerous studies using a Visual Analogue Scale invariably demonstrate that 20% of women in labour describe the pain as “unbearable” and 60% describe the pain as “very intense”. Since the mid-1980s, continuous epidural analgesia during labour has been considered the gold standard of labour anaesthesia and is currently the most frequently used. There are situations in which this type of analgesia could not be used. An alternative pain management is administration of parenteral opioids, the most frequently used of which is pethidine. Its use is associated with adverse effects and unsatisfactory analgesia. Since the second half of the 20th century, a new generation of opioids, such as fentanyl or remifentanil, has been used. Despite their much better pharmacokinetic and pharmacodynamic parameters, obstetricians, midwives and neonatologists are most aware of pethidine, probably because it has been used for the longest period of time, despite its disadvantages and the risk that its use entails. The drug that is nearest to ideal is remifentanil. The countries in which it is widely used as an alternative type of labour anaesthesia have developed practice standards or guidelines practice. Guidelines and alternatives to pethidine protocols for effective labour analgesia in Poland might be merited.Labour is thought to be one of the most intense and painful experiences in a woman’s life. Numerous studies using a Visual Analogue Scale invariably demonstrate that 20% of women in labour describe the pain as “unbearable” and 60% describe the pain as “very intense”. Since the mid-1980s, continuous epidural analgesia during labour has been considered the gold standard of labour anaesthesia and is currently the most frequently used. There are situations in which this type of analgesia could not be used. An alternative pain management is administration of parenteral opioids, the most frequently used of which is pethidine. Its use is associated with adverse effects and unsatisfactory analgesia. Since the second half of the 20th century, a new generation of opioids, such as fentanyl or remifentanil, has been used. Despite their much better pharmacokinetic and pharmacodynamic parameters, obstetricians, midwives and neonatologists are most aware of pethidine, probably because it has been used for the longest period of time, despite its disadvantages and the risk that its use entails. The drug that is nearest to ideal is remifentanil. The countries in which it is widely used as an alternative type of labour anaesthesia have developed practice standards or guidelines practice. Guidelines and alternatives to pethidine protocols for effective labour analgesia in Poland might be merited

Ewolucja próby bezdechu w rozpoznawaniu śmierci mózgu

The concept of brain death (BD) was initially described in 1959 and subsequently became widely accepted in the majority of countries. Nevertheless, the diagnostic guidelines for BD markedly differ, especially regarding the apnoea test (AT), a crucial element of clinical BD confirmation. The current basic guidelines recommend preoxygenation rather than disconnection from the ventilator and insertion of an oxygen insufflation catheter into the endotracheal tube. Although a properly prepared and conducted AT is relatively safe, it has to be aborted in cases of serious disturbances, such as severe cardiac arrhythmia, cardiac arrest, hypotension, hypercarbia, desaturation and tension pneumothorax. These complications may be more frequent in patients with previously existing risk factors, such as poor oxygenation, severe acidosis, hypotension and cardiac rhythm disturbances. Airway injuries can occur if the insufflation catheter is placed too deep or catheter-related obstruction of the intubation tube occurs. It is widely accepted that AT should be performed as the very last BD diagnostic procedure due to its possible lethal consequences. Reports concerning the possible pitfalls of AT and confounding situations have inspired attempts to determine the most effective and safe method of AT. The use of CPAP with oxygen supplementation is becoming highly popular. CPAP can be generated in three manners: directly by the ventilator; through the use of a CPAP valve with a reservoir; and through the use of a highly traditional T-piece system with a reservoir bag connected to distal tubing immersed in water.The concept of brain death (BD) was initially described in 1959 and subsequently became widely accepted in the majority of countries. Nevertheless, the diagnostic guidelines for BD markedly differ, especially regarding the apnoea test (AT), a crucial element of clinical BD confirmation. The current basic guidelines recommend preoxygenation rather than disconnection from the ventilator and insertion of an oxygen insufflation catheter into the endotracheal tube. Although a properly prepared and conducted AT is relatively safe, it has to be aborted in cases of serious disturbances, such as severe cardiac arrhythmia, cardiac arrest, hypotension, hypercarbia, desaturation and tension pneumothorax. These complications may be more frequent in patients with previously existing risk factors, such as poor oxygenation, severe acidosis, hypotension and cardiac rhythm disturbances. Airway injuries can occur if the insufflation catheter is placed too deep or catheter-related obstruction of the intubation tube occurs. It is widely accepted that AT should be performed as the very last BD diagnostic procedure due to its possible lethal consequences. Reports concerning the possible pitfalls of AT and confounding situations have inspired attempts to determine the most effective and safe method of AT. The use of CPAP with oxygen supplementation is becoming highly popular. CPAP can be generated in three manners: directly by the ventilator; through the use of a CPAP valve with a reservoir; and through the use of a highly traditional T-piece system with a reservoir bag connected to distal tubing immersed in water

The Neutrophil/Lymphocyte Count Ratio Predicts Mortality in Severe Traumatic Brain Injury Patients

Neutrophil-lymphocyte count ratio (NLCR) is a simple and low-cost marker of inflammatory response. NLCR has shown to be a sensitive marker of clinical severity in inflammatory-related tissue injury, and high value of NLCR is associated with poor outcome in traumatic brain injured (TBI) patients. The purpose of this study was to retrospectively analyze NLCR and its association with outcome in a cohort of TBI patients in relation to the type of brain injury

Computed tomographic angiography in the evaluation of brain death

According to Polish criteria two neurophysiological methods are used to demonstrate the cessation of brain function: electroencephalography (EEG) and brain stem auditory evoked potentials. Among the techniques measuring cerebral blood flow, conventional angiography of the four cerebral arterial axes is the reference standard for imaging brain death. Thus, it is an invasive examination which needs an experienced neuroradiologist and the availability of an angiography suite. The use of a computed tomographic (CT) scan to diagnose BD was proposed as early as 1978. This exam developed widely these last years thanks to a new generation of multirow CT which allows visualization of opacified cerebral vessels. The aim of the present study was to determine the accuracy of CT-a for the confirmation of BD. We examined four patients with suspicion of BD according to clinical criteria defined by law. CT scan was performed without and with injection of contrast material, followed by cerebral angiography. In our material CT-angiography showed opacification of A2-ACA in two patients (patient 1 and 2). In all our patients the results of CT-angiography fulfill the criteria proposed by the French Society of Neuroradiology in 2007 - absence of perfusion of M4 middle cerebral artery segments (M4-MCA) and deep cerebral veins. In conventional angiography one patient (patient 2) showed, at the level of the anterior and middle cerebral artery, a phenomenon already described as "stasis filling". CT angiography seemes to be a promising radiological exam in the diagnosis of BD. When confirmatory examinations are required among brain-dead patients for whom the clinical diagnosis remains essential, it may be an interesting alternative to conventional cerebral angiography, which is more invasive and constraining, and to EEG when it is unavailable or inadequate

Atypical Pupil Reactions in Brain Dead Patients

Background: During routine diagnosis of brain death, changes in pupil diameter in response to the stimulation of peripheral nerves are sometimes observed. For example, pupillary dilation after diagnosed brain death is described in the literature as the ciliospinal reflex. However, pupil constriction creates diagnostic doubts. Objective: The pupillometric analysis of pupil response to stimulation of the cervicothoracic spinal cord in patients with diagnosed brain death. Methods: Instrumental tests to confirm the arrest of cerebral circulation were performed in 30 adult subjects (mean age 53.5 years, range 26–75 years) with diagnosed brain death. In addition, a pupillometer was used to measure the change in pupil diameter in response to neck flexion. Intervention: Flexion of the neck and measuring the response in change of the pupil with the use of the pupillometer. Results: The change in the pupil was observed in the examined group of patients. Difference in pupil size ≥ 0.2 mm was observed in 14 cases (46%). In five cases (17%), pupil constriction was found (from 0.2 to 0.7 mm). Measurement error was +/− 0.1 mm. Conclusions: Both pupillary constriction and dilatation may occur due to a ciliospinal reflex in patients with brain death. This phenomenon needs further research in order to establish its pathophysiology

Melatonin and the Brain–Heart Crosstalk in Neurocritically Ill Patients—From Molecular Action to Clinical Practice

Brain injury, especially traumatic brain injury (TBI), may induce severe dysfunction of extracerebral organs. Cardiac dysfunction associated with TBI is common and well known as the brain–heart crosstalk, which broadly refers to different cardiac disorders such as cardiac arrhythmias, ischemia, hemodynamic insufficiency, and sudden cardiac death, which corresponds to acute disorders of brain function. TBI-related cardiac dysfunction can both worsen the brain damage and increase the risk of death. TBI-related cardiac disorders have been mainly treated symptomatically. However, the analysis of pathomechanisms of TBI-related cardiac dysfunction has highlighted an important role of melatonin in the prevention and treatment of such disorders. Melatonin is a neurohormone released by the pineal gland. It plays a crucial role in the coordination of the circadian rhythm. Additionally, melatonin possesses strong anti-inflammatory, antioxidative, and antiapoptotic properties and can modulate sympathetic and parasympathetic activities. Melatonin has a protective effect not only on the brain, by attenuating its injury, but on extracranial organs, including the heart. The aim of this study was to analyze the molecular activity of melatonin in terms of TBI-related cardiac disorders. Our article describes the benefits resulting from using melatonin as an adjuvant in protection and treatment of brain injury-induced cardiac dysfunction