Effect of hemorrhagic hypotension on hydroxyl radicals in cat brain.

This study investigated the relationships between blood pressure, cortical oxygen pressure and hydroxyl radicals in the brain of adult cats during hemorrhagic hypotension and retransfusion. Oxygen pressure in the blood of the cortex was measured optically by the oxygen dependent quenching of phosphorescence and hydroxyl radicals by in vivo microdialysis. Following a 2 h stabilization period after implantation of the microdialysis probe in the striatum, the mean arterial blood pressure (MAP) was decreased in a stepwise manner from 132 +/- 2 Torr (control) to 90 +/- 1 Torr, 70 +/- 3 Torr and 50 +/- 3 Torr, holding the pressure at each level for 15 min. The whole blood was then retransfused and measurements were continued for 90 min. Cortical oxygen pressure progressively decreased with decrease in MAP, decreasing from 50 +/- 2 Torr (control) to 42 +/- 1 Torr, 31 +/- 2 Torr and 22 +/- 2 Torr, respectively. The level of hydroxyl radical increased by 20-25% following first 15 min of bleeding and stay on this level during the remaining period of hypotension. Maximal increase (by 78%) in level of hydroxyl radicals was observed after 15 min of retransfusion. The present study demonstrated that during hypotension and retransfusion there was an increase in the level of hydroxyl radicals in striatum. These can be important mediators of postischemic injury to the striatum.

Response of cortical oxygen and striatal extracellular dopamine to metabolic acidosis in newborn piglets.

This study determined the relationships of metabolic acidosis, cortical oxygen pressure, and striatal extracellular dopamine in the brain of newborn piglets. After a baseline period of 120 minutes, a 0.6 N HCl solution was infused intravenously to decrease the blood pH to about 7.0-7.05. The metabolic acidosis was then corrected by injecting sodium bicarbonate and measurements were continued for one hour. The results show that decreased blood pH to about 7.2-7.15 does not cause a statistically significant change in mean blood pressure, cortical oxygen pressure or striatal extracellular dopamine. Further decrease in pH caused significant decrease in both blood pressure and cortical oxygen pressure. By the end of the period of acidosis the cortical oxygen pressure decreased from the control value of 43 +/- 4 Torr to 22 +/- 8 Torr. Changes in the extracellular level of striatal dopamine were parallel to changes in cortical oxygen pressure. The extracellular dopamine increased to 1270% of the control on the end of HCl injection. Infusion of bicarbonate to correct the acidosis resulted in an increase of cortical oxygen and progressive decline of dopamine in the extracellular medium. It is suggested that the level of extracellular dopamine in the striatum of newborn piglets was not directly affected by decrease in pH but was dependent on changes in tissue oxygen pressure during metabolic acidosis.

[The study of the evolution of laryngeal premalignant lesions]. / Estudio evolutivo de lesiones premalignas laríngeas.

Hyperkeratosis of the laryngeal epithelium is considered a clinically premalignant lesion that develops into invasive carcinoma in about 7-20% of cases. We reviewed 125 cases of patients with laryngeal keratosis in biopsy obtained by direct laryngocopy over a 10-year period. The evolution of these lesions to malignancy was conditioned by age, the presence of atypias in the initial lesions, and smoking; smoking is a modifiable factor. Surgery is the treatment of choice, with periodic follow-up for three to five years. The literature was reviewed.

[Acute respiratory obstruction caused by laryngeal rheumatoid arthritis]. / Obstrucción respiratoria aguda por artritis reumatoide laríngea.

We present a case of acute upper airway obstruction due to cricoarytenoid arthritis in severe rheumatoid arthritis. Although laryngeal involvement is common in severe rheumatoid arthritis, the upper airway obstruction is a very rare complication. The endotracheal intubation may be very difficult in these patients, thus fiberotopic bronchoscopy may be useful. Surgery is the final treatment.

[Aspergillosis of maxillary sinus: a case report]. / Aspergillosis de seno maxilar. A propósito de un caso.

A case of semi-invasive maxillary aspergillosis that presented with epiphora and responded well to surgical treatment is reported. Sixteen percent of cases of chronic sinusitis are produced by mycosis (particularly aspergillosis). The infection may be limited to the affected sinus (non-invasive forms) or may destroy the sinus wall, without tissue invasion (semi-invasive forms) or with tissue invasion (invasive forms). The diagnosis is mainly histological. Cultures present a high percentage of false positives and negatives. Treatment consists of surgical debridement of the sinus. Systemic amphotericin B is reserved for invasive aspergillosis (particularly fulminant cases).

[Instruments for the assessment of the needs of family members of patients in intensive care units: a systematic review]. / Instrumentos para la valoración de las necesidades de los familiares de pacientes ingresados en cuidados intensivos: una revisión sistemática.

The hospitalisation of a family member in an intensive care unit is a stressful event for the rest of the family members. During hospitalisation, the family suffers situations of fear, uncertainty and tiredness, and focuses on the medical evolution of their ill member. In this context, support and attention from health care professionals through the assessment of the needs of the family are crucial. There are different instruments for the assessment of a family's needs. This systematic review aims to identify these questionnaires and to critically analyse their characteristics, so as to offer professionals valid and reliable questionnaires that they can use when caring for families in critical units.

Effect of hemorrhagic hypotension on cortical oxygen pressure and striatal extracellular dopamine in cat brain.

This study investigated the relationships between blood pressure, cortical oxygen pressure, and extracellular striatal dopamine in the brain of adult cats during hemorrhagic hypotension and retransfusion. Oxygen pressure in the blood of the cortex was measured by the oxygen dependent quenching of phosphorescence and extracellular dopamine, dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) by in vivo microdialysis. Following a 2 h stabilization period after implantation of the microdialysis probe in the striatum, the mean arterial blood pressure (MAP) was decreased in a stepwise manner from 132 +/- 2 Torr (control) to 90 Torr, 70 Torr and 50 Torr, holding the pressure at each level for 15 min. The whole blood was then retransfused and measurements were continued for 90 min. As the MAP was lowered there was a decrease in arterial pH, from a control value of 7.37 +/- 0.05 to 7.26 +/- 0.06. The PaCO2 decreased during bleeding from 32.3 +/- 4.8 Torr to 19.6 +/- 3.6 Torr and returned to 30.9 +/- 3.9 Torr after retransfusion. The PaO2 was 125.9 +/- 15 Torr during control conditions and did not significantly change during bleeding. Cortical oxygen pressure decreased with decrease in MAP, from 50 +/- 2 Torr (control) to 42 +/- 1 Torr, 31 +/- 2 Torr and 22 +/- 2 Torr, respectively. A statistically significant increase in striatal extracellular dopamine, to 2,580 +/- 714% of control was observed when MAP decreased to below 70 Torr and cortical oxygen pressure decreased to below 31 Torr. When the MAP reached 50 Torr, the concentration of extracellular dopamine increased to 18,359 +/- 2,764% of the control value. A statistically significant decrease in DOPAC and HVA were observed during the last step of bleeding. The data show that decreases in systemic blood pressure result in decrease in oxygen pressure in the microvasculature of the cortex, suggesting vascular dilation is not sufficient to result in a full compensation for the decreased MAP. The decrease in cortical oxygen pressure to below 32 Torr is accompanied by a marked increase in extracellular dopamine in the striatum, indicating that even such mild hypoxia can induce significant disturbance in brain metabolism.

Relationships of dopamine, cortical oxygen pressure, and hydroxyl radicals in brain of newborn piglets during hypoxia and posthypoxic recovery.

The present study describes the relationships of extracellular striatal dopamine, cortical oxygen pressure, and striatal hydroxyl radicals in brain of newborn piglets during hypoxia and posthypoxic reoxygenation. Hypoxia was induced by reducing the fraction of inspired oxygen (FiO2) from 22% (control) to 7% for 1 h. The FiO2 was then returned to the control value and measurements were continued for 2 h. Cerebral oxygen pressure was measured by the oxygen dependent quenching of phosphorescence and extracellular levels of dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), and hydroxy radicals in the striatum were determined by in vivo microdialysis. Hypoxia decreased the cortical oxygen pressure from 47 +/- 2 to 9 +/- 1.3 torr (p < 0.001); the levels of extracellular dopamine in the striatum increased to 16,000 +/- 3,270% of control (p < 0.01), whereas the levels of DOPAC and HVA decreased to 25.3 +/- 6% (p < 0.001) and 36 +/- 5% (p < 0.01) of control, respectively. Compared with control, the hydroxyl radical levels at each time point were not significantly increased during hypoxia, although the sum of the measured values was significantly increased (p < 0.05). During the first 5 min after FiO2 was returned to 22%, the cortical oxygen pressure increased to control values and stayed at this level for the remainder of the measurement period. The extracellular level of dopamine declined to values not statistically different from control during 40 min of reoxygenation. During the first 10 min of reoxygenation, DOPAC and HVA further decreased and then began to slowly increase. By 70 min of reoxygenation, the values were not significantly different from control.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of the efficacy of blood and polyethylene glycol-hemoglobin in recovery of newborn piglets from hemorrhagic hypotension: effect on blood pressure, cortical oxygen, and extracellular dopamine in the brain.

BACKGROUND: Successful blood substitutes, when infused in place of an equal volume of whole blood, provide similar delivery of oxygen to the tissues without introducing abnormalities in cellular metabolism. STUDY DESIGN AND METHODS: Equal volumes of whole blood (control), polyethylene glycol-hemoglobin solution at 6 g per dL, dextran solution, and physiologic saline were compared for their ability to reverse the effects of hemorrhagic hypotension on oxygenation and dopamine metabolism in the brain of newborn piglets. The decrease in mean arterial blood pressure was used as a measure of the hemorrhagic insult. Cerebral oxygen pressure was determined optically by the oxygen-dependent quenching of phosphorescence, and the extracellular level of dopamine in the corpus striatum was determined by in vivo microdialysis. RESULTS: Following a 2-hour stabilization after implantation of the microdialysis probe in the corpus striatum, the mean arterial blood pressure was decreased from 88 +/- 7 torr (control) to 42 +/- 5 torr by the removal of blood in a stepwise manner, over a period of 60 minutes. Decrease in mean arterial blood pressure caused a progressive stepwise decrease in cortical oxygen pressure from 48 +/- 5 torr to 16 +/- 4 torr at the end of bleeding. As a consequence of the decrease in oxygen pressure, extracellular dopamine increased progressively to about 2300 percent of the control value. When a volume of blood equal to that removed was returned and bicarbonate was injected to help correct arterial pH, blood pressure, cortical oxygen pressure, and extracellular dopamine all returned within the 20- to 30-minute recovery period to values not significantly different from control values. An equal volume of polyethylene glycol-hemoglobin solution, even with significantly lower hemoglobin content than whole blood, gave results comparable to those with whole blood. CONCLUSION: Polyethylene glycol-hemoglobin solution, like whole blood but in contrast to physiologic saline or dextran solution, was capable of returning the mean arterial blood pressure, cortical oxygen pressures, and extracellular dopamine nearly to control levels after acute blood loss in newborn piglets.

Miasis cavitaria: reporte de un caso / Miasis cavitaria: reporte de caso / Cavitary myiasis: case report

La miasis es una enfermedad producida en tejidos o en cavidades corporales por la infestación de larvas de algunas especies de dípteros; su clasificación se hace según el sitio anatómico de infestación o de acuerdo al ciclo vital de la especie. En Colombia, la mayoría de los casos reportados de miasis cavitaria son debidos a Cochiliomyia hominivorax. Se reporta el caso de una paciente desnutrida con perforación del septo nasal, a quien al realizarle endoscopia nasal se le extraen once larvas vivas que posteriormente se envían al Laboratorio de Entomología del Instituto Nacional de Salud, en donde después de 22 días se obtienen moscas adultas de la familia Calliphoridae, género Cochliomyia, especie hominivorax...

Myiasis is an animal or human disease caused by parasitic dipterous fly larvae feeding on the host's necrotic or living tissue. Different classifications of myiasis can be adopted: description of myiasis by the infected area of the host, or accordingly with the biology of the fly species causing the myiasis and its likely effect. In Colombia most of the reported cases of cavity miasis are caused by Cochiliomyia hominivorax. A malnourished female patient is described with perforations in the nasal septo. A nasal endoscopy was performed to this patient and eleven alive larvae extracted and sent to the Laboratory of Entomology at the National Institute of Health. There, the larvea were given the appropriate development conditions for 22 days to finally obtained adult flies, which were identified in the Calliphoridae family, the Cochiliomyia gender and the hominivorax species...

A Miasis é uma doença produzida nos tecidos ou cavidades corporais pela infestação de larvas de algumas espécies de dípteros, sua classificação se faz segundo o lugar anatômico da infestação ou por o ciclo vital da espécie. Na Colômbia, A maioria dos casos reportados de miasis cavitaria são devidos à Cochiliomyia hominivorax. Reporta-se o caso de uma paciente desnutrida com perfuração do septo nasal, a quém ao realizar-lhe endoscopia nasal de llhe extraem onze larvas vivas que posteriormente se enviam ao laboratório de Entolologia do Instituto Nacional de Saúde, em onde depois de 22 dias de obtêm moscas adultas da família Calliphoridae, gênero Cochlomyia, espécie hominivorax...