Management of right-sided aortic arch aneurysms.

Specific technical problems are associated with the management of patients who have either of the two types of right-sided arches and aneurysms of the aortic arch and descending aorta. Two different approaches to addressing these problems, depending on the predominant congenital vascular anatomy, are presented.

Prospective randomized neurocognitive and S-100 study of hypothermic circulatory arrest, retrograde brain perfusion, and antegrade brain perfusion for aortic arch operations.

BACKGROUND: To determine the optimal method of brain protection during deep hypothermic circulatory arrest (DHCA) for arch repair. METHODS: Of 139 potential aortic arch repairs (denominator), we randomized 30 patients to either DHCA alone (n = 10), DHCA plus retrograde brain perfusion (RBP) (n = 10), or antegrade perfusion (ANTE) (n = 10); a further 5 coronary bypass (CAB) patients were controls. Fifty-one neurocognitive subscores were obtained for each patient at each of four intervals: preoperatively, 3 to 6 days postoperatively, 2 to 3 weeks postoperatively, and 6 months postoperatively. Intraoperative and postoperative S-100 blood levels and electroencephalograms were also obtained. RESULTS: For the denominator, the 30-day and hospital survival rate was 97.8% (136 of 139) and the stroke rate 2.8% (4 of 139). For the randomized patients, the survival rate was 100% and no patient suffered a stroke or seizure. Circulatory arrest (CA) times were not different (DHCA: RBP:ANTE) for 11 total arch repairs (including 6 elephant trunk; mean, 41.4 minutes; standard deviation, 15). Hemiarch repairs (n = 17) were quickest with DHCA (mean 10.0 minutes; standard deviation, 3.6; p = 0.011) and longest with ANTE (mean 23.8 minutes; standard deviation, 10.28; p = 0.004). Of the patients, 96% had clinical neurocognitive impairment at 3 to 6 days, but by 2 to 3 weeks only 9% had a residual new deficit (1 DHCA, 1 RBP, 1 ANTE), and by 6 months these 3 patients had recovered. Comparison of postoperative mean scores showed the DHCA group did better than RBP patients in 5 of 7 significantly different (p < 0.05) scores and versus 9 of 9 ANTE patients. There were no S-100 level differences between CA groups, but levels were significantly higher versus the CAB controls, particularly at the end of bypass (p < 0.0001); however, these may have been influenced by other variables such as greater pump time, cardiotomy use, and postoperative autotransfusion. Circulatory arrest (p = 0.01) and pump time (p = 0.057) correlated with peak S-100 levels. CONCLUSIONS: The results of hypothermic arrest have improved; however, there is no neurocognitive advantage with RBP or ANTE. Nevertheless, retrograde brain perfusion may, in a larger study, potentially reduce the risk of strokes related to embolic material. S-100 levels may be artificial. In patients with severe atheroma or high risk for embolic strokes, we use a combination of retrograde and antegrade perfusion on a selective basis.

Reduction of neurologic injury after high-risk thoracoabdominal aortic operation.

BACKGROUND: Of all aortic operations, thoracoabdominal aortic repairs have the highest risk of spinal cord neurologic injury, manifest by lower limb paraplegia or paraparesis. Cerebrospinal fluid drainage combined with intrathecal papaverine (CSFDr + IP) may reduce the risk and severity of neurologic injury. The objective of this study was to evaluate the effect of CSFDr + IP to prevent neurologic injury after high-risk thoracoabdominal aneurysm repairs. METHODS: We screened 64 patients before operation with descending thoracic or thoracoabdominal aneurysms for possible inclusion in a prospective, randomized study. Thirty-three patients with high-risk type I and II thoracoabdominal aneurysms met inclusion criteria and 17 were randomly assigned to CSFDr + IP and 16 to the control group. The study was terminated early after interim analysis revealed a significant difference. RESULTS: Of 64 patients screened, 2 patients died after operation (3.1%, 2/64); both were in the randomized study (6%, 2/33), and neither had a neurologic injury. Neurologic injury developed in 2 CSFDr + IP patients and 7 control patients (p = 0.0392). Control patients also had lower postoperative motor strength scores (p = 0.0340). On multivariate analysis, risk factors for neurologic injury included (p < 0.05) longer cross-clamp time, failure to actively cool with bypass, and postoperative hypotension, whereas CSFDr + IP was protective. Logistic regression showed that CSFDr + IP and active cooling significantly reduced the risk of injury and that the two combined modalities were additive. Of 64 patients screened, only 2 (3%) had a permanent neurologic deficit preventing ambulation. CONCLUSIONS: For high-risk thoracoabdominal aneurysms, CSFDr + IP was effective in reducing the incidence and severity of neurologic injury. Active cooling may be further additive to CSFDr + IP protection, although this needs to be confirmed in a larger study.

Identification of possible artifacts in the association of official analytical chemists sporicidal test.

Two laboratories tested four different brands of alkaline 2% glutaraldehyde sterilants by the Association of Official Analytical Chemists sporicidal test. Each laboratory found survival of Clostridium sporogenes spores on spore-labeled unglazed porcelain penicylinders (cylinders) to vary from test to test, and survival did not always correlate with increasing sterilant exposure time. These results were consistent with a theory that there may be random conditions within the test that prevent the sterilant from contacting all spores. Further studies indicated that the prior history of the unglazed porcelain cylinders and whether the C. sporogenes culture grown in egg-meat media had been processed (homogenized) to eliminate visible pieces of egg-meat media were important factors affecting the results and repeatability of this test.

Replacement of entire aorta from aortic valve to bifurcation during one operation.

A 68-year-old patient presented with an extensive aortic aneurysm extending from the aortic valve to the aortic bifurcation associated with severe continuous pain, dysphagia, and hoarseness. Because of the risk of impending rupture and an "elephant trunk" procedure not being an option, the entire aorta from the aortic valve to the aortic bifurcation was replaced during one operation using deep hypothermia with circulatory arrest and retrograde perfusion of the brain through the jugular veins. Seven months after the operation the patient walks more than 3 km a day and lives a normal life. The operative repair is presented.

Perioperative complications of anesthesia.

An overview of several perioperative complications and their management strategies is presented. Operative hypothermia, malignant hyperthermia, bronchospasm, and side effects of spinal opioid agents are discussed. Ramifications of these complications may extend well beyond the operative period and influence patient outcome. Therefore, it is necessary that the surgeon have a fundamental understanding of the pathophysiology and modalities of treatment in the context of anesthesia and surgery.

[Histologic studies of lymphatic tissue in sudden infant death]. / Histologische Untersuchungen des lymphatischen Gewebes beim plötzlichen Kindstod.

The lymphatic tissues (lymph nodes, spleen, thymus) were examined in 79 children who had died between the ages of one week and two years old. 59 of these children could be categorized as Sudden Infant Death because of their history and postmortem findings. In the remaining 20 cases a definite cause of death could be established. The demonstrated morphological reaction patterns which have different functional significances were differentiated and examined in detail. These revealed a substantial increase in indications of the occurrence of an acute infection in the infant organism in cases of Sudden Infant Death when compared to the control cases. A defect in the immunesystem could not be demonstrated by classical histomorphological methods.

[Histologic findings in the lung in sudden infant death]. / Histologische Lungenbefunde beim plötzlichen Kindstod.

The lungs of 79 children who had died between the ages of 1 week and 2 years old were histologically examined. 59 of these children could be categorized as cases of Sudden Infant Death because of the history and postmortem findings. In the remaining 20 cases a definite cause of death could be established. This is the same collective on which the histological investigations of the lymphatic tissue has been carried out. Morphological changes which are typical for a virus pneumonia were found in a substantially higher frequency in the cases of Sudden Infant Death than in the control cases. The validity of these findings and their possible significance for the cause of death are discussed.