[The administration of 20 ppm of inhaled nitric oxide produces a faster response than the inhalation of 5 ppm in adult respiratory distress syndrome]. / La administración de 20 ppm de óxido nítrico inhalado produce una respuesta más rápida que la inhalación de 5 ppm en el síndrome de distrés respiratorio del adulto.

OBJECTIVES: To compare the effects of 5 and 20 ppm of nitric oxide, evaluating time until response for each dose, in patients with adult respiratory distress syndrome (ARDS). PATIENTS AND METHODS: The study was prospective, controlled and random. Fifteen patients assigned to two groups received either 5 ppm (8 patients) or 20 ppm (7 patients) from November 96 to July 97. The main variables analyzed were PaO2/FiO2 and pulmonary vascular resistance index. We also studied etiology, severity of pulmonary damage as reflected by the Lung Injury Score, age, sex, Apache II prognostic score and exitus. Outcome was considered good if PaO2/FiO2 increased and/or pulmonary vascular resistance index decreased by more than 30% from the initial level (before inhalation of nitric oxide). RESULTS: The mean lung injury score was 2.9 +/- 0.4 and the two groups were homogeneous. Time until response to nitric oxide was significantly less in the 20 ppm group. Both PaO2/FiO2 and pulmonary vascular resistance index improved significantly in both groups whereas Qs/Qt improved only in the 20 ppm group. We also found that cardiac index and oxygen transport increased, the latter significantly only in the 20 ppm group. NO2 formation was less than 2 ppm and methemoglobin levels did not rise above 2%. CONCLUSIONS: Inhaled nitric oxide significantly improves oxygenation and decreases pulmonary vascular resistance without altering systemic vascular resistance during treatment of ARDS. The final outcomes were similar for both doses, but the 20 ppm dose produced a significantly faster response as well as a significant decrease in Qs/Qt.

La administración de 20 ppm de óxido nítrico inhalado produce una respuesta más rápida que la inhalación de 5 ppm en el síndrome de distrés respiratorio del adulto / An inhaled nitric oxide dose of 20 ppm produces a faster response than 5 ppm in adult respiratory distress syndrome

Objetivos. Comparar los efectos respectivos de 5 y 20 partes por millón (ppm) evaluando el tiempo de respuesta de ambas dosis, en pacientes con síndrome de distrés respiratorio del adulto.Métodos. El estudio fue prospectivo, controlado y aleatorio. Se estudió a 15 pacientes divididos en dos grupos, que recibían dosis de 5 ppm (grupo 5 ppm: 8 pacientes) o bien de 20 ppm (grupo 20 ppm: 7 pacientes), entre noviembre de 1996 y julio de 1997. Las variables principales analizadas fueron el índice PaO2/FiO2 y el índice de resistencias vasculares pulmonares. También se estudiaron la etiología, la gravedad de la lesión pulmonar según la Lung Injury Score (LIS), la edad, el sexo, el índice pronóstico APACHE II y la mortalidad. Se consideró resultado positivo el aumento del PaO2/FiO2 y/o la disminución del índice de resistencias vasculares pulmonares en más del 30 por ciento de los valores previos a la inhalación de NO.Resultados. El valor medio del LIS fue de 2,9 ñ 0,4. Los dos grupos eran homogéneos. El tiempo de respuesta al NO fue significativamente inferior en el grupo 20 ppm. Tanto el PaO2/FiO2 como el índice de resistencias vasculares pulmonares mejoraron significativamente en los dos grupos, y el Qs/Qt sólo en el grupo 20 ppm. También se observó aumento en el índice cardíaco y transporte de O2, que fue significativo sólo en el grupo 20 ppm. La formación de NO2 fue inferior a 2 ppm y la metahemoglobina no superó el 2 por ciento.Conclusiones. La inhalación de NO produjo mejoría significativa en la oxigenación y disminuyó significativamente las resistencias vasculares pulmonares, sin alterar las resistencias vasculares sistémicas, durante el tratamiento del síndrome de distrés respiratorio del adulto. Los efectos finales de ambas dosis fueron similares, pero las dosis de 20 ppm produjeron una respuesta significativamente más temprana y una disminución del Qs/Qt también significativa (AU)

[Comparative study of percutaneous tracheotomy and conventional surgical tracheotomy in patients with prolonged intubation]. / Estudio comparativo entre la traqueotomía percutánea y la traqueotomía convencional quirúrgica en pacientes con intubación prolongada.

BACKGROUND: Percutaneous tracheotomy (PT) has become an alternative to conventional surgical tracheotomy (CST) in recent years. Our aim was to compare the advantages and disadvantages of the two techniques in our intensive care unit (ICU). PATIENTS AND METHODS: Two patient groups were compared. Sixty underwent PT and 47 underwent CST, and all were admitted to the ICU between May 1995 and August 1997. PT was performed in 49 by way of progressive dilations, and 11 were performed by Griggs' method using a dilator. Variables studied were age, sex, reason for admission, APACHE II upon admission to the ICU, duration of technique, and immediate and late complications. Statistical analysis was provided by applying a Student t test to contrast quantitative variables and a chi-squared test to compare proportions. RESULTS: The following variables were significantly different. APACHE II upon admission was 18 +/- 5 in the PT group and 15 +/- 6 in the CST group (p < 0.002). Duration of the procedure was 15 +/- 4 minutes in the PT group and 36 +/- 11 in the CST group (p < 0.005). Complications after tracheotomy in PT group patients consisted of 1 false line during a change of cannula and 1 late tracheoesophageal fistula. Complications in the CST group included 16 episodes of slight bleeding, 9 stoma infections, 3 cases of pneumothorax, 2 of bad scarring of the stoma and 1 late fistula (p < 0.005). Time of follow-up was 41 to 76 days for PT patients and 32 to 51 days for CST patients. CONCLUSIONS: PT is a fast, simple procedure that is easy to manage and requires fewer resources (operating theater, personnel and equipment) and causes fewer medium-term complications than does CST.

[Synchronized independent pulmonary ventilation in the treatment of adult respiratory distress syndrome]. / Ventilación pulmonar independiente sincronizada en el tratamiento del síndrome de distrés respiratorio del adulto.

INTRODUCTION: Synchronized independent lung ventilation (SILV) is an effective mode of mechanical ventilation for treating both unilateral and bilateral pulmonary lesions. Oxygenation improves with an increase in the ventilation/perfusion ratio and also diminishes the risk of barotrauma. We describe our broad experience with this technique. Our main objective was to confirm whether SILV is able to improve the alveolar-arterial oxygen difference [P(A-a)O2] of patients with severe adult respiratory distress syndrome (ARDS) in whom conventional mechanical ventilation has not brought about improvement after being used for over 48 hours. PATIENTS AND METHODS: We carried out a descriptive, open, controlled prospective study of 45 patients with severe ARDS, enrolled from among 68 who underwent treatment with SILV. The most frequent cause of ARDS in our study was multiple trauma. The patients diagnosed of ARDS who did not improve with conventional mechanical ventilation were treated with SILV. Clinical characteristics and mortality are described. APACHE II scores, PAOA-aO2, dynamic distensibility were analyzed before and after SILV. The results of SILV were considered good if PA-aO2 improved at least 30% within 48 hours, with no increase in distensibility. RESULTS: No complications due to the technique were observed. Twenty-two patients (48.8%) died, 18 as a result of multiple organ failure and only one (4.5%) because of hypoxia. The improvements in APACHE II and (PA-aO2 were statistically significant, while distensibility did not change. The result was defined as good in most cases (n = 34, 83.8%). CONCLUSIONS: SILV is useful for providing ventilatory support when ARDS fails to improve with conventional mechanical ventilation. Clear improvement in respiratory function was observed, with significant decrease in PA-aO2 and no change in distensibility. SILV is a safe technique with few complications and can be managed by the intensive care unit nursing staff.

[Independent pulmonary ventilation as a treatment in the re-expansion of atelectasis]. / Ventilación pulmonar independiente como tratamiento en la reexpansión de atelectasias.

Two patients with respiratory failure were treated with independent lung ventilation (ILV). During their clinical course they developed atelectasis without response to usual therapies. The use of ILV and selective positive end-expiratory pressure (S-PEEP) allowed lung expansion and oxymetric improvement. With the ILV plus S-PEEP we tried to correct the abnormal ventilation/perfusion ratio. ILV plus S-PEEP increases both the ventilation in the highly perfused areas, and the functional residual capacity selectively in the pathologic lung in unilateral affection cases.