Dexmedetomidine for awake craniotomy without laryngeal mask

OBJECTIVE: This paper reports the use of dexmedetomidine in three epileptic patients with cavernous angiomas that underwent awake surgery in order to map their speech areas. METHOD: Loading dose of dexmedetomidine varied from 1 microg/Kg/h to 3 microg/Kg/h over 20 minutes and maintenance dose from 0.4 microg/Kg/h to 0.8 microg/Kg/h. RESULTS: There was no occurrence of hemodynamic instability, convulsions or respiratory depression. Patients tolerated well the procedure. CONCLUSION: Dexmedetomidine was useful for awake craniotomy as it decreased patients level of consciousness but did not produce agitation. Laryngeal mask was not necessary to keep air ventilation.

OBJETIVO: Este trabalho relata o uso de desmedetomidina em três pacientes com angiomas cavernosos próximos a área de linguagem e epilepsia que foram operados acordados para mapeamento cortical. MÉTODO: A dose de ataque de dexmedetomidina variou de 1 mg/Kg/h a 3 mg/Kg/h durante 20 minutos e dose de manutenção de 0,4 mg/Kg/h a 0,8 mg/Kg/h. RESULTADOS: Os pacientes toleraram bem o procedimento e não houve instabilidade hemodinâmica, convulsões ou depressão respiratória. CONCLUSÃO: Dexmedetomidina foi útil nas craniotomias com o paciente acordado para mapeamento cortical pois gerou sedação sem agitação. A máscara laríngea não foi necessária para manter a ventilação nesses pacientes.

Hemodynamic changes during dynamic exercise in patients after mitral valve replacement for chronic mitral regurgitation.

To evaluate hemodynamic changes during dynamic exercise, we investigated 13 patients after mitral valve replacement (MVR) for chronic mitral regurgitation (MR) and 5 control subjects by right heart catheterisation during supine bicycle exercise. According to the sizes of the St. Jude Medical (SJM) prosthesis during MVR, patients were divided into group A (n = 8) with SJM 31mm and group B (n = 5) with SJM 29mm. Significant rise in cardiac index (CI) was noted during exercise in both groups A and B (from 3.3 +/- 0.8 to 5.5 +/- 0.9 l/min/m2, p < 0.01 and from 3.0 +/- 0.6 to 5.6 +/- 0.6 l/min/m2, p < 0.01 respectively) and also in control subjects (from 3.4 +/- 0.7 to 6.2 +/- 0.6 l/min/m2, p < 0.01). Mean pulmonary artery and pulmonary capillary wedge pressure were significantly higher during exercise in patients of both groups A and B than control subjects (p < 0.05 and p < 0.01 respectively). Total pulmonary vascular resistance was significantly higher during exercise in both groups A and B than control subjects (p < 0.05 and p < 0.01 respectively). No difference in hemodynamics were noted between the patients of group A and B during exercise. It is concluded that response of CI to exercise in patients after MVR for chronic MR was adequate in comparison to control subjects irrespective of two different valve sizes.