Ricardo Borges Magaldi

Effect of a Protective-Ventilation Strategy on Mortality in the Acute Respiratory Distress Syndrome

BACKGROUND In patients with the acute respiratory distress syndrome, massive alveolar collapse and cyclic lung reopening and overdistention during mechanical ventilation may perpetuate alveolar injury. We determined whether a ventilatory strategy designed to minimize such lung injuries could reduce not only pulmonary complications but also mortality at 28 days in patients with the acute respiratory distress syndrome. METHODS We randomly assigned 53 patients with early acute respiratory distress syndrome (including 28 described previously), all of whom were receiving identical hemodynamic and general support, to conventional or protective mechanical ventilation. Conventional ventilation was based on the strategy of maintaining the lowest positive end-expiratory pressure (PEEP) for acceptable oxygenation, with a tidal volume of 12 ml per kilogram of body weight and normal arterial carbon dioxide levels (35 to 38 mm Hg). Protective ventilation involved end-expiratory pressures above the lower inflection point on the static pressure-volume curve, a tidal volume of less than 6 ml per kilogram, driving pressures of less than 20 cm of water above the PEEP value, permissive hypercapnia, and preferential use of pressure-limited ventilatory modes. RESULTS After 28 days, 11 of 29 patients (38 percent) in the protective-ventilation group had died, as compared with 17 of 24 (71 percent) in the conventional-ventilation group (P<0.001). The rates of weaning from mechanical ventilation were 66 percent in the protective-ventilation group and 29 percent in the conventional-ventilation group (P=0.005): the rates of clinical barotrauma were 7 percent and 42 percent, respectively (P=0.02), despite the use of higher PEEP and mean airway pressures in the protective-ventilation group. The difference in survival to hospital discharge was not significant; 13 of 29 patients (45 percent) in the protective-ventilation group died in the hospital, as compared with 17 of 24 in the conventional-ventilation group (71 percent, P=0.37). CONCLUSIONS As compared with conventional ventilation, the protective strategy was associated with improved survival at 28 days, a higher rate of weaning from mechanical ventilation, and a lower rate of barotrauma in patients with the acute respiratory distress syndrome. Protective ventilation was not associated with a higher rate of survival to hospital discharge.

Impacto de biópsia pulmonar a céu aberto na insuficiência respiratória aguda refratária

OBJECTIVE: To determine the impact that open lung biopsy findings have on decisions regarding changes in the treatment strategies employed for critically ill patients presenting diffuse pulmonary infiltrates and suffering from refractory acute respiratory failure, as well as on their clinical improvement. METHODS: This study involved 12 mechanically ventilated patients with acute respiratory failure who were subjected to open lung biopsy (by thoracotomy) after not presenting a clinical response to standard treatment. RESULTS: The single most common cause of the acute respiratory failure was viral infection, which was identified in 5 patients (40%). The pre-operative evaluation of the cause of respiratory failure was modified in 11 patients (91.6%), and a specific diagnosis was made in 100% of the cases. Regardless of changes in treatment regimen, the mortality rate was 50%. Six patients (50%) survived to be discharged from the hospital. All of the discharged patients survived for at least one year after the open lung biopsy, for an overall one-year survival rate of 50% among the 12 patients studied. For the patients who died in the hospital, the time of survival after open lung biopsy was 14 + 10.8 days. CONCLUSION: We conclude that open lung biopsy is a useful tool in the management of acute respiratory failure when there is no clinical improvement after standard treatment, since it can lead to a specific diagnosis that requires distinct treatment, which probably lowers the mortality rate among such patients.

Distonia aguda relacionada ao uso de bromoprida em pacientes pediátricos

abstRact Objective: To report the case of two patients with acute dystonia induced by bromopride in children, followed by a review of the mechanisms of induction of movement dis-orders by antidopaminergic anti-emetic drugs, its clinical symptoms and treatment. Case description : Case 1: a 13 years old teenager who developed acute hypertonia and neck pain associated to fever and vomiting, suggestive of meningitis. Further investi-gation revealed that symptoms were associated with the ingestion of a single dose of bromopride. The symptoms stopped after administration of diphenidramine, preventing a spinal tap. Case 2: six months old infant who developed extrapyramidal movement disorder related to bromopride overdose, with prompt resolution of symptoms after treat-ment with biperiden. Comments: This seems to be the first report of acute dystonia after the use of bromopride in children. Although frequently used in Brazil as an anti-emetic and prokynetic agent, no clinical study has showed that bromopride has a better safety profile than other antidopaminergic anti-emetic drugs. While such studies are not available, caution is needed in the context of pediatric prescription of bromopride. Non pharmacological measures should be adopted in the manage-ment of vomiting and gastroesophageal reflux. If medical treatment cannot be avoided, one would rather use medica-tions with a better established safety profile.

Estudo da preservação do pulmão de cão mantido em autoperfusão

Foram estudados 14 blocos coracao-pulmao (BCP), nos quais os pulmoes foram mantidos em sistema de autoperfusao em periodo de duas ate oito horas. Realizaram-se biopsias pulmonares a cada duas horas. Dez blocos mantiveram-se preservados ate a quarta hora com pequena intensidade de alteracao, demonstrada semiquantitativamente atraves de estudo estrutural. A partir desse tempo, edema intra-alveolar, hemorragia perivasculo-bronquial, hemorragia intra-alveolar, enfisema perivasculo-bronquia e rotura alveolar ocorreram com maior intensidade.