Dados do Trabalho

Título

Ocular motility in the diagnosis of coma

RESUMO

A 52-year-old male, obese, hypertensive and non-dialytic chronic renal patient underwent coronary artery bypass graft surgery and wide endarterectomy, with sixty-five minutes of cardiopulmonary bypass (CPB) and forty-five minutes of aortic clamping time, without intercurrences. He progressed in the postoperative period with weaning from vasoactive drugs, maintenance of renal function and reduction of mediastinal drain output. Sedation was turned off 48 hours after the surgical procedure, without awakening or adequate respiratory driving after five days. On physical examination, the patient remained in a comatose state (Glasgow coma scale 3/15), with mild alternating conjugate ocular deviations. A cranial tomography was requested, which showed an increase in the density of the basal ganglia symmetrically and of the thalamus.
In the intensive care unit, ocular signs may have prognostic, diagnostic and therapeutic value. Changes such as ptosis, nystagmus and pupillary dilation have different diagnostic values and can help in a faster and more adequate management of the case. In postoperative cardiac surgery units, especially in procedures with cardiopulmonary bypass, cerebrovascular accidents (CVA) should always be included in the list of differential diagnoses, since up to 14% of patients can develop CVA, as well as intraoperative hypoxic lesions. The roving conjugate eye is a slow, conjugated, lateral and symmetrical movement, characteristic of coma and suggestive of ischemic or metabolic lesions. Imaging exams may present without significant changes, which does not exclude brain injury.
In the case in question, despite the reduced CPB time and the absence of significant metabolic changes, the risk factor of obesity and the need for endarterectomy may have led to small ischemic lesions, in addition to cardiopulmonary bypass, which constitutes a risk factor isolated for hypoxic and ischemic injuries.
Ophthalmological examination is an important step in the physical examination of patients in intensive care and should be a widespread knowledge among attending physicians. Although there are imaging tests that complement and guide, sometimes they become insufficient in the diagnosis, and the clinical examination is an indispensable tool for better management of the patient.