A randomized controlled trial of prophylactic intra-aortic balloon counterpulsation in high-risk aneurysmal subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: To assess whether prophylactic postoperative intraaortic balloon counterpulsation (IABC) reduces the risk of poor outcome because of vasospasm following aneurysmal subarachnoid haemorrhage relative to conventional hypervolemic therapy (HT). METHODS: This was a single-center, parallel group randomized controlled trial. Patients suffering a subarachnoid hemorrhage at high risk of vasospasm were eligible. Patients were randomly allocated to receive prophylactic IABC (n=35) or HT (n=36). The primary end point was Glasgow Outcome and SF-36 scores assessed at 6 months by a blinded and independent observer and analyzed by intention to treat. Secondary analysis of physiological parameters was by treatment performed. RESULTS: Twenty-seven patients in each arm had a good outcome (P=0.55). There was no statistical difference in mean SF-36 score (t=0.39, P=0.70). There were no long-term complications secondary to IABC. There were no differences in preload (pulmonary artery wedge pressure, P=0.97) or afterload (mean arterial pressure, P=0.97). IABC was associated with a lower cardiac output (P=0.002) and higher systemic vascular resistance (P=0.005), although for both groups mean cardiac output was >6 L/min. Cerebral blood flow was not different between groups: HT=41.5 (SD 7.2), IABP=44.9 (SD 8.6) mL/100 g/min (P=0.14). CONCLUSIONS: In this study, prophylactic IABC did not improve perfusion indices or confer any clinical benefit following subarachnoid haemorrhage in patients with normal cardiac function. The study was small, however, and cannot be extrapolated to patients with cardiac failure and medically refractory symptomatic cerebral vasospasm. Clinical Trial Registration- This trial was not registered because enrolment began prior to July 1, 2005.

The SILVER (Silver Impregnated Line Versus EVD Randomized trial): a double-blind, prospective, randomized, controlled trial of an intervention to reduce the rate of external ventricular drain infection.

BACKGROUND: Cerebrospinal fluid (CSF) infections associated with external ventricular drain (EVD) placement attract major consequences. Silver impregnation of catheters attempts to reduce infection. OBJECTIVE: To assess the efficacy of silver catheters against CSF infection. METHODS: We performed a randomized, controlled trial involving 2 neurosurgical centers (June 2005 to September 2009). A total of 356 patients requiring an EVD were assessed for eligibility; 325 patients were enrolled and randomized (167 plain, 158 silver); 278 patients were analyzed (140 plain, 138 silver). The primary outcome measure was CSF infection as defined by organisms seen on Gram stain or isolated by culture. Secondary outcome measures included ventriculoperitoneal (VP) shunting. RESULTS: There was a significant difference in infection risk between the 2 study arms: 21.4% (30/140) for plain catheters vs 12.3% (17/138) for silver catheters (P = .0427; 95% confidence interval [CI]: 1.015-3.713). Patients who had an EVD infection had more than double the risk of requiring a VP shunt compared with patients without an EVD infection (45.7% [21/46] vs 19.7% [45/229], respectively, P = .0002; 95% CI: 1.766-6.682). There was also a significant difference in VP shunt risk with infection: plain (55.2%; 16/29) vs the silver arm (29.4%; 5/17); P = .0244 (95% CI: 1.144-11.695). A multivariate analysis demonstrated that infection risk was increased by duration of EVD placement (odds ratio: 1.160), spontaneous intracranial hemorrhage (odds ratio 4.958) and decreased by silver catheters (odds ratio: 0.423). CONCLUSION: The study provides Class I evidence that silver-impregnated catheters reduce CSF infection.