• Table of Contents
• Fluid Management

XII. Brain Protection

       A. Hypothermia
	  - potential problems: coagulation problems may
            be seen, often will be a difficult wake up.

            1. For moderate hypothermia, 33.5 to 34.0 oC,
               drop off the edge, drift down to moderate 
	       levels without active cooling.

            2. For cranial base surgery, active cooling
               is needed.  Don't cover the leg from which
               the fat will be harvested. Set the cooling
               blanket to 22 oC.

       B. Thiopental

            1. There exists a range of opinion as to what
               the optimal dose of thiopental for brain
               protection is. The best way to titrate it
               is to observe the effects on the EEG tracing.
               Newfield and Cottrell recommend a loading
               dose of 15mg/kg with maintenance at
               12mg/kg/hr as a starting point for
               rendering the EEG isoelectric. In the
               average patient, a bolus of about 300 to
               500 mg followed by an infusion of
               7mg/kg/hr will produce 50% burst
               suppression. In one patient, burst
               suppression was achieved with with 350mg
               of pentothal in 3 divided doses
               (150+100+100). Another technique for
               inducing burst suppression is to
               administer 5-75mg every 30 seconds till
               the endpoint is acheived. One series of 7
               patients required 6-12mg/kg/hr to maintain
               burst suppression after a loading dose of
               3mg/kg. (?3-5mg/kg - Spetzler)

            2. High dose thiopental will necessitate some
               treatment of the hypotension that results.
               There are two schools of thought on how
               blood pressure should be treated. Newfield
               and Cottrell suggests that the order of
               steps taken to regain normotension is
               fluids, dopamine, phenylephrine. Others
               state that if the brain is supplied with
               enough blood pressure, autoregulation will
               result in adequate perfusion. These
               authors suggest going to phenylepherine (neo)
               rather than dopamine. In either case, it
               is important that fluids	be adequate, 
	       especially blood. 

       C. Other agents

            1. Pentobarbital vs. Thiopental vs. Phenobarbital



    XIII. Coagulation Considerations

       A. TEG