Marino The ICU Book 4e, IE

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Disorders of Consciousness

The Potential Organ Donor For the potential organ donor, the following measures can be used to en- hance organ viability (36). Hemodynamics Potential organ donors should have a mean arterial pressure ≥ 65 mm Hg and a urine output ≥ 1 mL/kg per hour, and fluids and vasopressors should be used, if necessary, to achieve these goals. Circulatory support for the potential organ donor should follow the same principles of circu- latory support used for other critically ill patients (see pages 270 – 272). Pituitary Failure More than half of patients with brain death will develop pituitary failure with diabetes insipidus and secondary adrenal insufficiency (37). Both condi- tions can lead to profound hypovolemia (with reduced organ perfusion) and hypertonic hypernatremia (with cell dehydration). If there is evi- dence of central diabetes insipidus (i.e., spontaneous diuresis with a urine osmolality below 200 mOsm/L), treatment with desmopressin , a vasopressin analog that does not cause vasoconstriction, is advised (38). The usual dose of desmopressin is 0.5 – 2.0 µg IV every 2 – 3 hours, with dose titration to maintain a urine output of 100 – 200 mL/hr.

A FINALWORD

Family Care In the care of the patient with persistent coma or a persistent vegetative state, spending time with the patient’s family (or other intimates) is as important as patient care. These people will look to you for guidance, and avoiding the conspiracy of silence (39) is one of the greatest services you can perform as a physician.

REFERENCES

Altered Consciousness 1. León-Carrión J, van Eeckhout P, Dominguez-Morales Mdel R. The locked-in syndrome: a syndrome looking for a therapy. Brain Inj 2002; 16:555–569. 2. The Multi-Society Task Force on PVS. Medical aspects of the persistent veg- etative state (Part 1). N Engl J Med 1994; 330:1499–1508. 3. Bleck TP, Smith MC, Pierre-Louis SJ, et al. Neurologic complications of criti- cal medical illnesses. Crit Care Med 1993; 21:98–103. 4. Papadopoulos M, Davies D, Moss R, et al. Pathophysiology of septic encephalopathy: a review. Crit Care Med 2000; 28:3019–3024.