Abstract: INTRODUCTION. Brain damage is the most common cause of morbidity and mortality after initial recovery of a cardiac arrest. AIM. To review the usefulness of transcranial Doppler ultrasonography (TCD) in monitoring and prognosis of comatose patients after initial recovery from cardiac arrest. DEVELOPMENT. The TCD records the velocity and pulsatility of cerebral blood flow, allowing 'beat to beat' hemodynamic analysis, with the added value of not being interfered by the use of sedatives or therapeutic treatments such as moderate hypothermia. In patients who remain comatose two hours after being recovered from cardiac arrest, persistence in the cerebral arteries of a diffuse hypodynamic TCD pattern (low medium velocity and high pulsatility) also predicts poor neurologic recovery. Early or late presence of a diffuse hyperdynamic TCD pattern (high medium velocity and low pulsatility) is also associated with poor prognosis because progression to intracranial hypertension and brain death. Coincidence of hypodynamic arteries and other with normal or hyperdynamic TCD patterns, suggests foci of hypoperfusion that may be predictors of stroke. CONCLUSIONS. Using serial TCD examinations in comatose patients after initial recovery from cardiac arrest, to detect and treat early changes in cerebral hemodynamics, will decrease the likelihood of secondary neurological damage. In the first 24 hours, TCD could identify patients who have progressed to irreversible neurological damage, thus avoiding therapeutic futility.
Abstract: Less than 10% of those individuals who suffer an episode of sudden cardiac arrest are successfully resuscitated and return home to live productive lives. New approaches to cardiac resuscitation could substantially improve such dismal outcome. Four current trends that have the greatest potential for improving outcome can be recognized in cardiopulmonary resuscitation (CPR): (1) systems to prevent cardiac arrests through recognition of early warning signs and timely intervention, (2) a shift towards a flow-based resuscitation emphasizing the delivery of high-quality uninterrupted CPR limiting the role of ventilation, (3) the growing role of technology in driving resuscitation interventions, incrementally enhancing the human decision-making process, and (4) the use of hypothermia.
Abstract: A higher prevalence of cardiac right-to-left shunt through a patent foramen ovale (PFO) has been recently reported in the irritable bowel syndrome (IBS). At the same time, signs of ischemia in medullary cerebral microcirculation and the presence of excess sympathetic activity in peripheral circulation have been identified, both related with change in pain perception and autonomic dysfunction characteristic of IBS. Considering these findings together, the possible etiopathogenic role of PFO in the development of IBS can be proposed, because the paradoxical embolism characteristic of PFO could damage the cerebral and intestinal microcirculation, and that injury would be also amplified by the percentage of venous blood that shunts the pulmonary filter, producing an alteration in the metabolism of serotonin, pro-inflammatory bradykinins or neurotensin, substances with a proven etiopathogenic relationship with IBS.
Abstract: More than 50,000 people suffer annually in Spain an episode of out-of-hospital cardiac arrest, but less than 10% of those individuals are successfully resuscitated and return home to live productive lives. The application of the scientific evidence available in resuscitation could substantially improve such dismal outcome. However, most of the procedures that have been able to reduce mortality are not sufficiently being used in Spain. In addition to the development of really intense strategies for early defibrillation, 4 current aspects in resuscitation have the greatest potential for improving outcome: a) prevention of cardiac arrests through recognition of early warning signs and timely intervention; b) flow-based cardiopulmonary resuscitation limiting the role of ventilation; c) use of technology in driving resuscitation interventions, and d) use of hypothermia.
Abstract: BACKGROUND AND OBJECTIVE: Both irritable bowel syndrome (IBS) and patent foramen ovale (PFO) have a similar prevalence in the general population, affect more commonly women and are related to comorbidities such as migraine. In IBS there are alterations in the metabolism of certain substances like serotonin. In the presence of PFO with a right- to left-shunt (RLS), a percentage of venous blood bypasses the lung filter and may increase these substances in blood. PATIENTS AND METHOD: A phone interview was done to determine the presence of IBS in patients previously attended for detection of RLS with transcranial Doppler ultrasound. The presence and grade of RLS was analyzed and compared with subjects without gastrointestinal symptoms (NoGI). Rome II criteria were used to diagnose IBS or other functional gastrointestinal disorder (FGD) and Venice 1999 consensus were used for the diagnosis of RLS. RESULTS: Thirthy-three (18.3%) of 180 interviewed patients had IBS and 62 (34.4%) other FGD. RLS was found in 41% of NoGI patients, 64% of patients with IBS and 68% of patients with other FGD (odds ratio [OR] = 2.56; p < 0.05 for SII, and OR = 3.06; p < 0.01 for other FGD). RLS with a massive pattern was registered in en 27% of NoGI patients, 39% of patients with IBS and 45% of patients with other FGD (OR = 1.73; p = 1 for IBS, and OR = 2.21; p < 0.05 for other FGD). CONCLUSIONS: We found a higher prevalence of cardiac RLS through a PFO in patients with IBS and other FGD. A possible etiopathogenic relationship must be considered in future studies.
Abstract: BACKGROUND AND PURPOSE: A major concern during carotid artery stent placement is the potential for cerebral embolism. Diminishing the number of device manipulations across the lesion might reduce procedural stroke risk. For this purpose, we report our initial experience with carotid stent placement without the use of either balloon angioplasty or distal protection devices. MATERIALS AND METHODS: Eighty-seven consecutive patients with 100 carotid stenoses compose this series. Ninety four of the 100 hundred stented carotid arteries were either symptomatic (58 [58%]) or had a greater than 70% stenosis (36 [36%]). Six percent of them were asymptomatic and had stenosis between 50% and 70%. Patients underwent neurologic evaluation before the procedure and during follow-up at 1, 3, 6, and 12 months and annually thereafter. Carotid sonography and plain films of the neck were performed immediately after the procedure and then at the same time intervals. RESULTS: Primary stent placement was successful in 98 of 100 case subjects. In 2 case subjects, predilation was necessary before stent deployment. Neurologic periprocedural complications included 1 nondisabling and 1 disabling stroke and 5 transient ischemic attacks. The mean duration of follow-up was 23 months (range: 10-36 months). During the follow-up period, there were 5 deaths, all unrelated to the carotid disease, and no major stroke. The degree of stenosis decreased from a mean of 78.85% before the procedure to a mean of 21.23% immediately after. CONCLUSIONS: In this series, carotid stent placement without the use of either balloon angioplasty or distal protection devices was safe and effective with a low incidence of periprocedural complications.
Abstract: It is considered that in Spain, every year, we have more than 24,500 out-of-hospital cardiac arrests. Around 85% of these are secondary to ventricular fibrillation, with possibility of reversion in more than 90% if defibrillation is performed in the first minute of arrhythmia. However, if we delay this defibrillation, survival possibilities disappear in a few minutes. Clinical advances in last decades have not achieved satisfactory results in the treatment of cardiac arrest as survival rates at hospital discharge do not exceed 7%. Aware of this situation, the International Scientific Societies are recommending decreasing time to defibrillation, advising, at best, a time less than five minutes between the 112-call (emergency) and adequate electric discharge. Development of automated defibrillators in Emergency Medical Systems and their use by <<first responders>> of <<non-health care>> emergency services (police, fire fighters, etc) contribute to reach this objective. Because of this, Emergency Medical Systems are modifying their assistance strategies, to implement the early defibrillation as <<key to survival>>. Literature showed the effective value of automated defibrillators in the public areas but their efficiency level is less than that reached with the Emergency Services. Efficiency depends on multiple factors such as type of installation, accessibility level to emergency medical services or incidence rate of sudden cardiac arrest. Thus, their introduction should be preceded by a cost-effectiveness study. Effectiveness of automated defibrillators at home, where up to 80% of cardiac arrest are produced, has still not been evaluated. Nevertheless, in the USA, its marketing with this indication has been authorized.
Abstract: A frequent finding in healthy individuals, patent foramen ovale (PFO) with right-to-left shunt (RLSh), is an embrionary residue that has been linked with cryptogenic stroke and peripheral ischemia. Pulmonary hypertension and entities like decompression illness, migraine with aura or plathypnea-orthodeoxia have been found to have a higher prevalence of PFO with RLSh. Some dementias and unexplained syncopes could also have some relationship. Paradoxical embolism, thrombosis of the foramen channel or the atrial structures with subsequent embolism, transient arrhythmias, prothrombotic states and vasoactive substances passage have been proposed as physiopathologic mechanisms involved. Contrast-enhanced transesophageal echocardiography is the standard reference diagnostic procedure but contrast-enhanced transcranial Doppler is a good non-invasive alternative diagnostic tool that is highly sensitive and specific.
Abstract: INTRODUCTION: Transcranial oximetry (TCO) is a new method to measure continuous changes in brain blood oxygen saturation (rSO2) by using near-infrared spectroscopy (NIRS). To our knowledge, no studies about TCO in air medical transport have been published. METHODS: Twenty healthy volunteers (HEMS medical crew) were investigated during flight missions without patients. We measured oxygen saturation (SpO2), cardiac rate, and rSO2 with an INVOS 4100 Cerebral Oximeter at sea level and at each 1000 feet until we reached a flight level of 5000 feet. RESULTS: The oximeter did not produce any interference with medical or aeronautical equipment. Subjects' SpO2 showed a slight decrease with altitude (P < 0.010), but rSO2 remained constant (P = 0.28), with little delay in the physiological correction of SpO2 and rSO2 values. CONCLUSION: TCO may play an important role in the development of new monitoring methods for critical patients in air medical transport. Further studies with large sample sizes and patients are necessary to generalize findings.
Abstract: No studies had been conducted about Spanish HEMS programs, so we conducted a nationwide survey by phone from January to June 1999. We identified 18 HEMS programs in 13 regions, which transported 4870 patients in 1998. The primary/interhospital missions ratio was 51.25/48.75. In 78% of responding programs, the medical crew was a physician and a nurse. Only 33% of HEMS had standard medical equipment; most lacked noninvasive blood pressure monitors, and one-third of the medical personal were correctly protected with flight helmets and flight suits. It is necessary to study the cost-effectiveness of the Spanish model of HEMS.
Abstract: The results of electrical transcutaneous cardiac stimulation (ETCCS) were evaluated in 38 emergency situations seen at the Emergency Service of the Hospital 12 de Octubre (Madrid) during one year. ETCCS is a noninvasive stimulation procedure through electrodes placed on the chest surface (negative left sub-mamillary and positive right infraclavicular--AA--or left subscapular--AP2--). The stimulation impulse has a duration of 0.01-0.04 seconds depending on the type of device used, with intensities which can achieve 200 mA and stimulation frequencies up to 180/min. The high electrical (97.4%) and mechanical (75.7%) effectiveness of ETCCS in our series, its acceptable tolerance (80.1% of the conscious patients) and its easy management have led us to support the use of electrocardiographic monitor-defibrillator-ETCCS units for the complete early electrical support of emergencies associated with disorders of the cardiac rhythm. This support may be given in emergency areas with minimal training requirements.
