Luis Vicente Garcia

Use of neuron-specific enolase for assessing the severity and outcome of neurological disorders in patients

Neuron-specific enolase (NSE) is a glycolytic enzyme present almost exclusively in neurons and neuroendocrine cells. NSE levels in cerebrospinal fluid (CSF) are assumed to be useful to estimate neuronal injury and clinical outcome of patients with serious clinical manifestations such as those observed in stroke, head injury, anoxic encephalopathy, encephalitis, brain metastasis, and status epilepticus. We compared levels of NSE in serum (sNSE) and in CSF (cNSE) among four groups: patients with meningitis (N=11), patients with encephalic injuries associated with impairment of consciousness (ENC, N=7), patients with neurocysticercosis (N=25), and normal subjects (N=8). Albumin was determined in serum and CSF samples, and the albumin quotient was used to estimate blood-brain barrier permeability. The Glasgow Coma Scale score was calculated at the time of lumbar puncture and the Glasgow Outcome Scale (GOS) score was calculated at the time of patient discharge or death. The ENC group had significantly higher cNSE (P=0.01) and albumin quotient (P=0.005), but not sNSE (P=0.14), levels than the other groups (Kruskal-Wallis test). Patients with lower GOS scores had higher cNSE levels (P=0.035) than patients with favorable outcomes. Our findings indicate that sNSE is not sensitive enough to detect neuronal damage, but cNSE seems to be reliable for assessing patients with considerable neurological insult and cases with adverse outcome. However, one should be cautious about estimating the severity of neurological status as well as outcome based exclusively on cNSE in a single patient.

Effects of intrathecal sufentanil on plasma oxytocin and cortisol concentrations in women during the first stage of labor.

Background and Objectives Intrathecal sufentanil provides analgesia comparable to epidural bupivacaine for the first stage of labor. Both epidural local anesthetics and intrathecal opioid reduce some parameters of the neuroendocrine response to labor pain and the reflex release of oxytocin in animals. In humans, epidural local anesthetics only reduce the spurt release of oxytocin. This study compared the effect of intrathecal sufentanil and epidural bupivacaine administration on the plasma concentration of oxytocin and cortisol in women with labor pain during the first stage of labor. Methods Thirty healthy parturients requesting analgesia were enrolled in this randomized and open-label study. Each patient was in spontaneous labor at greater than 5 cm cervical dilatation. Using a combined spinal and epidural technique, patients received either intrathecal sufentanil 10 μg (SUF = intrathecal sufentanil group) or epidural plain bupivacaine 0.25%, 12 mL (BUPIV = epidural bupivacaine group). Analgesia was assessed using a visual analog scale, and blood samples for oxytocin and cortisol plasma concentration measurements were collected immediately before analgesia and 15, 30, 60, and 90 minutes after induction of the analgesia. Plasma cortisol and oxytocin concentrations were determined by specific radioimmunoassay. The values were expressed as mean ± SEM. Results Intrathecal sufentanil provided faster and more complete analgesia within 15 and 30 minutes of its administration, compared with epidural bupivacaine. Plasma oxytocin concentrations were similar in the 2 groups before analgesia (7.24 ± 2.1 and 6.6 ± 3.1 pg/mL SUF and BUPIV, respectively). It decreased significantly in the SUF and increased in the BUPIV after analgesic administration. Cortisol concentrations were elevated in both groups before analgesia (51.6 ± 5.3 and 54.2 ± 4.8 μg/dL SUF and BUPIV, respectively). Both analgesic treatments significantly decreased the plasma cortisol levels. Conclusions Intrathecal sufentanil analgesia decreases plasma concentrations of oxytocin and cortisol in women with labor pain during the first stage of labor, but epidural bupivacaine only reduced the cortisol concentration.

Oxytocin interference in the effects induced by inhalation of 7.5% CO2 in healthy volunteers

The objective of this study was to assess the acute effect of intranasally administered oxytocin (OT) on subjective states, cardiovascular, and endocrine parameters in healthy volunteers who inhaled 7.5% CO2.

Postoperative management of severe acute anemia in a Jehovah's Witness

Low levels of hemoglobin (Hb) are not rare in patients who refuse blood components but this case is unique due to the severity of anemia and the possibility that her previous episode of acute normovolemic hemodilution has influenced her outcome.

Effects of Dexmedetomidine-Fentanyl Infusion on Blood Pressure and Heart Rate during Cardiac Surgery in Children

Background. The purpose of this study was to access the effects of dexmedetomidine-fentanyl infusion on blood pressure (BP) and heart rate (HR) before surgical stimulation, on their changes to skin incision, and on isoflurane requirement during cardiac surgery in children. Methods. This study had a prospective, randomized, and open-label design. Thirty-two children aged 1 month to 10 years undergoing surgery for repair congenital heart disease (CHD) with CPB were randomly allocated into two groups: group MDZ received midazolam 0.2 mg·kg−1·h−1 and group DEX received dexmedetomidine 1 μg·kg−1·h−1 during the first hour followed by half of these rates of infusions thereafter. Both group received fentanyl 10 μg·kg−1, midazolam 0.2 mg·kg−1 and vecuronium 0.2 mg·kg−1 for induction. These same doses of fentanyl and vecuronium were infused during the first hour then reduced to half. The infusions started after induction and maintained until the end of surgery. Isoflurane was given briefly to control hyperdynamic response to skin incision and sternotomy. Results. In both groups, systolic blood pressure (sBP) and heart rate (HR) decreased significantly after one hour of infusion of the anesthetic solutions, but there were significantly less increase in diastolic blood pressure, sBP, and HR, and less patients required isoflurane supplementation to skin incision in the patients of the DEX group. Discussion. Dexmedetomidine infusion without a bolus appears to be an effective adjunct to fentanyl anesthesia in control of hemodynamic responses to surgery for repair of CHD in children.

Labor analgesia in a patient with paroxysmal nocturnal hemoglobinuria with thrombocytopenia

Background and Objectives Paroxysmal nocturnal hemoglobinuria (PNH) is a form of acquired hemolytic anemia in which a defect of glycophosphoinositol anchor proteins in the cell membrane of bone marrow stem cells leads to activation of the complement system and consequent destruction of defective cells. The characteristics of this disease are an increased frequency of thrombotic events, anemia, and thrombocytopenia. Methods We report a case of a pregnant patient with PNH with thrombocytopenia who delivered vaginally after receiving epidural labor analgesia. Prophylaxis of thromboembolism was performed with heparin 1 hour after the removal of the epidural catheter, and repeated at 12-hour intervals. Sensory changes or motor changes and pain were monitored every 10 minutes for 8 hours after delivery. Results During analgesia, the patient reported complete pain relief. Delivery and the immediate postpartum period were without any untoward events. Conclusions Four major factors influenced the anesthetic conduct used for the present patient: (1) the risk of an acute hemolytic crisis, (2) the need to perform prophylaxis for thromboembolism, (3) the need to reduce labor stress, and (4) minimizing the risk of missing an epidural hematoma. We also present a survey of the literature about PNH and discuss the anesthetic conduct in this patient.

Uso do azul de metileno no tratamento de choque anafilático durante anestesia: relato de caso

BACKGROUND AND OBJECTIVES The risk of perioperative anaphylaxis should always be considered. The incidence of anesthetic allergic reactions is controversial, varying from 1/3,000 to 1/20,000, with mortality range between 3 and 9%. This report describes the use of methylene blue as coadjuvant drug to treat anaphylaxis refractory to conventional therapy. CASE REPORT A 53-year-old male patient was submitted to inguinal hernia correction under spinal anesthesia. After receiving 1.5 g intravenous dipirone at surgery completion, he immediately developed bronchospasm, cyanosis, decreased SpO2 and SBP, culminating with cardiac arrest. Resuscitation was started with external cardiac massage followed by tracheal intubation, as well as 1 mg epinephrine and 1 mg atropine injections. Heart rate returned (150 bpm) with no palpable pulse though. Additional 1 mg epinephrine and 1 g hydrocortisone were administered with central pulse recovery (8 minutes). Although receiving dopamine (20 microg.kg-1.min-1), patient remained hypotensive (60 mmHg) until 80 minutes. Intravenous 100 mg methylene blue was then administered with increased SBP to 85 and 105 mmHg after the second dose. Dopamine dose was tapered from 10 to 7, 5 and finally 2 microg.kg-1.min-1. CONCLUSIONS Histamine is the major anaphylaxis mediator. Inducing nitric oxide (NO) production, it consequently increases guanylate cyclase, which promotes arteriolar vasodilation by increasing cyclic GMP. Methylene blue may be helpful in such situations because it inhibits guanylate cyclase and consequently vasodilation, resulting in hemodynamic improvement.

Comparison of the area of the pharynx during wakefulness and induced sleep in patients with Obstructive Sleep Apnea (OSA)

UNLABELLED The study of obstructive sleep apnea (OSA) has received growing attention over the past years since various aspects have not been sufficiently established. AIM To evaluate, with the use of magnetic resonance imaging (MRI), changes in the area of the pharynx during wakefulness and induced sleep in patients with OSA. MATERIALS AND METHODS A prospective study of thirty-two patients with a polysomnographic diagnosis of OSA. All patients were submitted to MR imaging in order to obtain high-definition anatomical sagittal sequences during wakefulness and during sleep induced with Propofol. An area was defined on the sagittal plane in the midline of the pharynx. This region was called pharyngeal midplane (PMP) area. RESULTS A significant difference in PMP area (mm²) was observed between wakefulness and induced sleep in each patient (p < 0.000001). CONCLUSION The patients with OSA suffer a significant reduction of 75.5 % in the area of the pharynx during induced sleep compared to wakefulness.

Neuron-specific enolase in patients with neurocysticercosis

BACKGROUND Neurocysticercosis (NC) is the most frequent parasitic disease of the human nervous system. Its clinical manifestations are varied and depend on the number and location of cysts, as well as the host immune response. Symptoms in NC usually occur when cysts enter into a degenerative phase associated with perilesional inflammation. We speculate that neuron-specific enolase (NSE)--a marker of neuronal injury--could be elevated in patients with degenerating cysts comparing to those with viable cysts. METHODS We examined serum NSE (sNSE) and cerebrospinal fluid (CSF) NSE (cNSE) levels in 25 patients with NC: 14 patients with degenerative cysts (D), 8 patients with viable cysts (V) and 3 patients with inactive cysts. Samples of eight normal controls (C) were also obtained. Determination of albumin was performed in serum and CSF samples, and the CSF/serum albumin ratio (albumin quotient, Q(alb)) was used to estimate the blood-brain barrier permeability. RESULTS All patients, with the exception of one case, had five or less cysts. Comparisons between V, D and C groups did not demonstrate significant differences of cNSE, Q(alb) and sNSE levels. Further, there were no significant differences of cNSE and sNSE levels between patients with or without intracranial hypertension (ICH). CONCLUSIONS These findings suggest that the inflammatory response associated with a relatively small number of degenerating cysts does not provoke significant neuronal damage. Further studies considering patients with a larger number of cysts will be required to assess if there is evidence of neuronal damage in such more severe cases.

Hemodynamic Effects of the Combination of Dexmedetomidine-Fentanyl versus Midazolam-Fentanyl in Children Undergoing Cardiac Surgery with Cardiopulmonary Bypass

BACKGROUND AND OBJECTIVES To evaluate the efficacy of the combined infusion of dexmedetomidine and fentanyl on the hemodynamic response during cardiac surgery with cardiopulmonary bypass (CPB) in children. METHODS Thirty-two children, ages 1 month to 10 years, scheduled for cardiac surgery with cardiopulmonary bypass were randomly divided in two groups: the MDZ Group received midazolam 0.2 mg.kg(-1).h(-1), while the DEX group received dexmedetomidine 1 microg.kg(-1).h(-1) during one hour followed be a reduction by half in the rate of infusion in both groups. Both groups received fentanyl 10 microg.kg(-1), midazolam 0.2 mg.h(-1), and vecuronium 0.2 mg.kg(-1) for anesthesia induction. The same doses of fentanyl and vecuronium used during induction were infused during the first hour after induction, followed by a reduction to half. Infusions were initiated immediately after induction and maintained until the end of the surgery. Isoflurane was administered for a short time to control the hyperdynamic response to incision and sternotomy. RESULTS In both groups, systolic blood pressure and heart rate reduced significantly after one hour of anesthetic infusion, but the increase in systolic and diastolic pressure and heart rate to skin incision were significantly lower in the DEX Group. A significantly lower number of patients demanded supplementation with isoflurane in the DEX Group. After CPB, patients in both groups had similar hemodynamic responses. CONCLUSIONS Infusion of dexmedetomidine without bolus seems to be an effective adjuvant to fentanyl on the promotion of sedation and control of hemodynamic responses during surgery for congenital cardiopathies in children.