Síndrome compartimental agudo extremidad inferior después de cirugía cardíaca / Acute compartment syndorme lower extremity after cardiac surgery

El síndrome compartimental agudo en el postoperatorio de cirugía cardiaca bajo circulación extracorpórea y especialmente tras revascularización miocárdica quirúrgica, es una complicación grave que se presenta de manera excepcional en las primeras horas del postoperatorio, requiere para su diagnóstico un alto nivel de sospecha y precisa de actuación quirúrgica urgente. Presentamos un caso de síndrome compartimental en la extremidad inferior de un paciente afecto de patología valvular aórtica degenerativa y enfermedad coronaria asociada, sometido a remplazo valvular por prótesis y bypass aortocoronario con injertos venosos y arterial, con especial atención hacia el mecanismo fisiopatológico que desencadena esta grave complicación, necesidad de un diagnóstico preciso y precoz y atención quirúrgica inmediata (AU)

Acute compartmental syndrome in the postoperative period of cardiac surgery with cardiopulmonary bypass, especially aftercoronary artery bypass graft surgery is a severe complication that rarely occurs during the firsts hours after surgery; diagnosis requires a high level of suspicion and emergency surgical treatment. We report a case of compartmental syndrome of lower extremity in a patient with degenerative aortic valve disease and associated coronary disease, who underwent valve replacement and aortocoronary bypass with venous ad arterial grafts, pointing at the pathophysiological mechanisms that triggers this serious complication, and the need for early and accurate diagnosis and inmmediate surgical management (AU)

Playing harp, another unusual task-specific dystonia.

Herein we report a task-specific dystonia in a 48-year-old woman, with an unusual association between a familial harp-playing dystonia and essential tremor.

Amyotrophic lateral sclerosis IgG-treated neuromuscular junctions develop sensitivity to L-type calcium channel blocker.

In order to search for early changes induced by the application of human immunoglobulin G (IgG) on motor nerve terminals, IgG from patients with amyotrophic lateral sclerosis (ALS) and control subjects was injected subcutaneously into the levator auris muscle of mice. A week or a month after the last injection, endplate potentials were recorded. No changes in quantal content of transmitter release were observed. In control and ALS IgG-treated muscles, neurotransmitter release remained sensitive to P/Q-type and insensitive to N-type voltage-sensitive calcium channel (VSCC) blockers as in untreated muscles. In contrast, IgG from 5 of 8 different ALS patients induced a significant reduction in quantal content of the evoked response after incubation with nitrendipine, indicating that a novel sensitivity to this calcium channel blocker appears in these motor nerve terminals. These results indicate that ALS IgG induces plastic changes at nerve terminals. The expression of transmitter release coupled to L-type VSCC indicate that ALS IgGs are capable of inducing plastic changes at the nerve terminals that may participate in the process leading to neuronal death.

SEPs and CNS magnetic stimulation in syringomyelia.

Somatosensory evoked potentials (SEPs) and motor evoked potentials (MEPs) to transcranial and spinal stimulation from upper and lower limb muscles were elicited in 13 patients with syringomyelia. Seven had an associated Chiari type I anomaly. Diagnosis was confirmed by MRI. In 5 cases, SEPs and MEPs were performed before and after surgical treatment. Prolonged central motor conduction times or absent motor responses in upper or lower limbs were found in most patients. The greatest number of abnormalities was disclosed by measurement of CMCT followed by SEPs after tibial nerve stimulation. Two of 5 cases undergoing surgery improved clinically and showed reduction in CMCT after surgical treatment. Our study shows that MEPs were useful in the evaluation of neurophysiological status in syringomyelia patients, helping to estimate anterolateral spinal cord function.

Electric vs magnetic trans-cranial stimulation of the brain in healthy humans: a comparative study of central motor tracts 'conductivity' and 'excitability'.

Motor evoked potentials (MEPs) were elicited in the thenar muscles of 11 healthy volunteers via individual electric unifocal and magnetic trans-cranial stimuli (TCS). The effects of TCS strength, of the muscular state (relaxed, contracted) as well as of the amplitude-latency characteristics and the duration of the motor tracts central conduction times (CCTs) to hand muscles, were evaluated and compared between the two types of brain excitation. MEPs with the shortest latency (18.91 +/- 1.31 ms) were recorded in the voluntarily contracted muscle during electric TCS, whilst those with maximal latency (23.3 +/- 1.63 ms) were found after magnetic TCS with an intensity at threshold for eliciting an MEP of about 0.1 mV in the relaxed muscle. Mean CCTs for electric and magnetic TCS calculated in the contracted target muscles, were respectively 5.07 +/- 0.51 and 6.34 +/- 0.46 ms. MEPs with larger amplitudes and durations were observed during magnetic TCS, being maximal when suprathreshold stimuli were delivered. A restricted range of liminar values of magnetic TCS was obtained by defining the threshold for raising motor responses in complete muscle relaxation, indicating that magnetic pulses might represent a useful probe for testing the 'excitability' of the motor tracts.