Faculty Bibliography

BACKGROUND: Although neurogenic stunned myocardium (NSM) after aneurysmal subarachnoid hemorrhage (SAH) is well described, its clinical significance remains poorly defined. We investigated the influence of left ventricular (LV) dysfunction and cerebral vasospasm on cerebral infarction, serious cardiovascular events, and functional outcome after SAH. METHODS: Of the 481 patients enrolled in the University Columbia SAH Outcomes Project between 10/96 and 05/02, we analyzed a subset of 119 patients with at least one echocardiogram, serial transcranial Doppler (TCD) data, and with no prior history of cardiac disease. LV dysfunction was defined as an ejection fraction <40% on echocardiography. Infarction from vasospasm was adjudicated by the study team after comprehensive review of all clinical and imaging data. Functional outcome was assessed at 15 and 90 days with the modified Rankin Scale (mRS). RESULTS: Eleven percent of patients had LV dysfunction (N = 13). Younger age, hydrocephalus, and complete filling of the quadrigeminal and fourth ventricles were associated with LV dysfunction (all P < 0.05). Despite a similar frequency of pre-existing hypertension, 0% of patients with LV dysfunction reported taking antihypertensive medication, compared to 35% of those without (P = 0.009). There was a significant association between LV dysfunction and infarction from vasospasm after adjusting for clinical grade, age, and peak TCD flow velocity (P = 0.03). Patients with LV dysfunction also had higher rates of hypotension requiring vasopressors (P = 0.001) and pulmonary edema (P = 0.002). However, there was no association between LV dysfunction and outcome at 14 days after adjustment for established prognostic variables. CONCLUSIONS: LV dysfunction after SAH increases the risk of cerebral infarction from vasospasm, hypotension, and pulmonary edema, but with aggressive ICU support does not affect short-term survival or functional outcome. Antihypertensive medication may confer cardioprotection and reduce the risk of catecholamine-mediated injury after SAH.

OBJECT: The purpose of this study was to identify predictors of shunt-dependent hydrocephalus after aneurysmal subarachnoid hemorrhage (SAH). METHODS: The authors evaluated the incidence of shunt-dependent hydrocephalus in a consecutive cohort of 580 patients with SAH who were admitted to the Neurological Intensive Care Unit of Columbia University Medical Center between July 1996 and September 2002. Patient demographics, 24-hour admission variables, initial CT scan characteristics, daily transcranial Doppler variables, and development of in-hospital complications were analyzed. Odds ratios and 95% CIs for candidate predictors were calculated using multivariate nominal logistic regression. RESULTS: Admission glucose of at least 126 mg/dl (adjusted OR 1.6; 95% CI 1.0-2.6), admission brain CT scan with a bicaudate index of at least 0.20 (adjusted OR 1.43; 95% CI 1.0-2.0), Fisher Grade 4 (adjusted OR 2.71; 95% CI 1.2-5.7), fourth ventricle hemorrhage (adjusted OR 1.78; 95% CI 1.1-2.7), and development of nosocomial meningitis (adjusted OR 2.2; 95% CI 1.4-3.7) were independently associated with shunt dependency. CONCLUSIONS: These data suggest that permanent CSF diversion after aneurysmal SAH may be independently predicted by hyperglycemia at admission, findings on the admission CT scan (Fisher Grade 4, fourth ventricle intraventricular hemorrhage, and bicaudate index >/= 0.20), and development of nosocomial meningitis. Future research is needed to assess if tight glycemic control, reduction of fourth ventricle clot burden, and prevention of nosocomial meningitis may reduce the need for permanent CSF diversion after aneurysmal SAH.

The need for organ donation has become a growing concern over that last decade as the gap between organ donors and those awaiting transplant widens. According to UNOS, as of 8/2009, there were 102,962 patients on the transplant waiting list and only 6,004 donors in 2009 (UNOS.org. Accessed 4/8/2009). In 2008, an estimated 17 patients died each day awaiting transplant (OPTN.org). Though currently most organ donations come after brain death (DND or donation after neurological death), tissue donation (cornea, skin, bone, and musculoskeletal tissue), and donation after cardiac death (DCD) and are also possible. The term "extended criteria donor" refers to potential donors over 60 years of age or age 50-59 years plus 2 of the 3 following criteria: stroke as the cause of death, creatnine > 1.5 meq/dl, or a history of hypertension. Historically, extended criteria donors have had a lower organ yield per donor. In order to preserve the choice of organ donation for the family, intensive management of the potential organ donor is necessary. Since each potential donor could save seven lives or more, nihilism in the care of such patients can have far reaching ramifications. This article describes intensive care management practices that can optimize organ donation.

To address the gap between organs available for transplant and the number of patients on the transplant waiting list, the Joint Commission on the Accreditation of Healthcare Organizations, Institute of Medicine, United Network for Organ Sharing and the federal government have recommended the increased used of donation after cardiac death (DCD) (JCAHOnline http://www.jointcommission.org/Library/JCAHOnline/jo_06.06.htm ; UNOS, Highlights of the June Board Meeting, 2006). DCD is defined as organ donation once death is declared after irreversible cessation of circulatory and respiratory functions, as opposed to brain death (donation after neurological death). Though DCD is one of the fastest growing categories of organ donors, it comprises only 8% of all deceased donors (Steinbrook in N Engl J Med 357:209-213, 2007). Prior to 1968, when the Ad Hoc Committee of Harvard Medical School proposed a neurological definition of death based on brain-death criteria, organs from deceased donors came from patients who had suffered cardio-pulmonary demise (IOM, Non-heart-beating organ transplantation: practice and protocols, 2000). Early transplantation from DCD donors met with limited success and most transplant surgeons turned to brain-dead donors. Consequently, DCD fell out of vogue and, until recently, has not been the focus of transplant initiatives.

OBJECTIVE: Hypertensive hypervolemic therapy is widely used to treat symptomatic vasospasm after subarachnoid hemorrhage. Few data exist to support a relationship between early clinical response and mortality or functional outcome. METHODS: In a prospective cohort of 580 subarachnoid hemorrhage patients, we studied 95 patients with acute symptomatic vasospasm who received stepwise volume expansion with crystalloid and/or 5% albumin solution followed by intravenous pressors to maintain systolic blood pressure between 180 and 220 mm Hg. We separately assessed the effects of volume expansion and induced hypertension on the neurological examination during the first 2 hours of each intervention. We used multivariate logistic regression analysis to calculate adjusted odds ratios assessing the relationship between clinical response to hypertensive hypervolemic therapy and 3-month outcome, as measured by the modified Rankin Scale. RESULTS: Of 95 patients with symptomatic vasospasm, volume expansion was used in 94% (n = 89), of whom 43% had a clinical response; 85% of the patients (n = 81) received pressors, of whom 68% responded. Early clinical improvement attributable to either volume expansion or pressors was not related to the development of infarction on computed tomography, but response to either modality within 2 hours was independently protective against death (adjusted odds ratio, 0.03; P < 0.05) and death-or-severe-disability (modified Rankin Scale score, 4-6; adjusted odds ratio, 0.1; P < 0.05) after adjusting for age, Hunt-Hess grade, angioplasty, and aneurysm size. CONCLUSION: Subarachnoid hemorrhage patients with symptomatic vasospasm who fail to demonstrate early clinical improvement in response to volume or pressor therapy are at high risk for death or disability. Urgent endovascular intervention in this high-risk patient cohort may be justified.