Neurologic deficit in patients at high risk with thoracoabdominal aortic aneurysms: the role of cerebral spinal fluid drainage and distal aortic perfusion.

PURPOSE: This prospective study evaluated the possible prevention of postoperative neurologic deficit in patients at high risk with thoracoabdominal aortic aneurysms (TAAA), types I and II, by use of perioperative cerebrospinal fluid drainage and distal aortic perfusion. METHODS: Between September 18, 1992, and August 8, 1993, 45 consecutive patients underwent TAAA repair (14 type I, 31 type II). Thirty-six were men and nine were women. The median age was 63 years (range 28 to 88). Twenty-four of 45 patients (53%) had dissection and 17 of 45 (38%) had prior proximal aortic replacement. All patients underwent perioperative cerebrospinal fluid drainage and distal aortic perfusion. Median aortic clamping time was 42 minutes. Thirty-five of 45 patients (78%) underwent intercostal artery reattachment. RESULTS: The 30-day survival rate was 96% (43 of 45 patients). Early neurologic deficit occurred in two of 45 patients (4%), and late neurologic deficit also occurred in two of 45 patients (4%). We compared the neurologic deficit of our current group of 45 patients with the data of a previously unpublished study of 112 patients also from this center. Total neurologic deficit for the current group was four of 45 (9%) versus the previous group of 35 of 112 (31%) with a p value of 0.0034 (Pearson chi-square test). Neurologic deficit for patients with type I TAAA was 0 of 14 (0%) versus 15 of 73 (21%) (p = 0.062); for patients with type II TAAA 4 of 31 (13%) versus 20 of 39 (51%) (p = 0.0008). In patients with aortic dissection, neurologic deficit was 3 of 24 (12%) versus 9 of 32 (28%) (p = 0.0304); no dissection was 1 of 21 (5%) versus 26 of 80 (32%) (p = 0.011). For aortic clamp times less than 45 minutes, neurologic deficit was 1 of 24 (4%) versus 14 of 68 (21%) (p = 0.061); for aortic clamp times equal to or greater than 45 minutes, neurologic deficit was 3 of 21 (14%) versus 21 of 44 (48%) (p = 0.0090). CONCLUSION: Neurologic deficit in patients treated for types I and II TAAA was reduced significantly by perioperative cerebral spinal fluid drainage and distal aortic perfusion.

Accurate determination of left ventricular ejection fraction by transesophageal echocardiography with a nonvolumetric method.

The multiple diameter method previously described and validated for transthoracic echocardiography (TTE) determines ejection fraction (EF) by use of the average of several left ventricular (LV) diameters from multiple views measured at the base, midthird, and distal third of the LV combined with an estimate of the shortening fraction of the long axis (delta L). This method may be ideal for transesophageal echocardiography (TEE) because it does not require tracing of the endocardial contour or volume determinations. Accordingly, EF was calculated with the multiple diameter method in 20 patients in whom TTE and TEE were performed within 1 hour of each other. EF by TTE averaged 49% +/- 20% and ranged from 14% to 80%. The multiple diameter method was modified for TEE as follows: (1) three diameters were taken from the four-chamber view (base, mid-LV, and distal LV) and four from the transgastric view (approximately at 45 degrees from each other), (2) because the LV apex is not well seen by TEE, delta L was estimated from the descent of the mitral anulus towards the apex as 0.15, 0.10, 0.05, or 0 for a descent of > or = 10, 6 to 9, 3 to 5 or < or = 2 mm, respectively. EF by TEE averaged 48% +/- 21% and correlated very well with EF by TTE (r = 0.98; y = 1.03x-2.7). The diameter method was tested prospectively in 30 patients undergoing coronary artery bypass surgery. TEE and TTE were performed within 5 minutes of each other with the patients asleep before initiation of surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

Brain protection via cerebral retrograde perfusion during aortic arch aneurysm repair.

Eleven patients underwent resection and graft replacement of ascending and aortic arch aneurysms. Retrograde cerebral perfusion was used during the procedures to minimize cerebral ischemia. Retrograde cerebral perfusion (15 degrees to 24 degrees C) was administered through the superior vena cava. The mean cerebral ischemic time was .35 minutes (range, 11 to 71 minutes). Throughout retrograde cerebral perfusion, blood samples were drawn from the innominate and left carotid arteries at 1, 5, and every 10 minutes thereafter for analysis of arterial oxygen content, total creatine kinase level, and creatine kinase BB fraction. All patients survived. All except 1 awoke neurologically intact. In this patient, electroencephalogram and transcranial Doppler studies conducted before circulatory arrest were consistent with embolic phenomena. There was no significant difference between the current group's intraoperative electroencephalograms and those of a similar historical group. Postoperative complications included transient renal failure, myasthenia gravis, cholecystitis, premature atrial contractions, atrial fibrillation, and vocal cord paralysis. The creatine kinase BB fraction range was 1.8 to 13.4. The increase of total creatine kinase level was due to MM fraction. Retrograde cerebral perfusion during circulatory arrest is a valuable adjunct for protecting the brain. The creatine kinase BB band was not a good marker to detect brain injury. With continued use of this technique and accumulation of a larger series, we may better define the role of retrograde cerebral perfusion in brain protection.