Impact of the fluid challenge infusion rate on cardiac stroke volume during major spinal neurosurgery: a prospective single center randomized interventional trial.

BACKGROUND: Fluid therapy, including the choice of a crystalloid or colloid infusion, the execution time of a volume bolus, and the expected volume need of a patient during surgery, varies greatly in clinical practice. Different goal directed fluid protocols have been developed, where fluid boluses guided by dynamic preload parameters are administered within a specific period. OBJECTIVE: To study the efficacy of two fluid bolus infusion rates measured by the response of hemodynamic parameters. DESIGN: Monocentric randomized controlled interventional trial. SETTING: University hospital. PATIENTS: Forty patients undergoing elective major spinal neurosurgery in prone position were enrolled, thirty-one were finally analyzed. INTERVENTIONS: Patients were randomly assigned to receive 250 ml crystalloid and colloid boluses within 5 min (group 1) or 20 min (group 2) when pulse pressure variation (PPV) exceeded 14%. MAIN OUTCOME MEASURES: Changes in stroke volume (SV), mean arterial pressure (MAP), and catecholamine administration. RESULTS: Group 1 showed a greater increase in SV (P = 0.031), and MAP (P = 0.014), while group 2 still had higher PPV (P = 0.005), and more often required higher dosages of noradrenalin after fluid administration (P = 0.033). In group 1, fluid boluses improved CI (P < 0.01), SV (P < 0.01), and MAP (P < 0.01), irrespective of whether crystalloids or colloids were used. In group 2, CI and SV did not change, while MAP was slightly increased (P = 0.011) only after colloid infusion. CONCLUSIONS: A fluid bolus within 5 min is more effective than those administered within 20 min and should therefore be the primary treatment option. Furthermore, bolus infusions administered within 20 min may result in volume overload without achieving relevant hemodynamic improvements. TRIAL REGISTRATION: German Clinical Trials Register: DRKS00022917.

Arteriovenous malformations of the filum terminale: clinical characteristics, angioarchitecture, and management of a rare spinal vascular pathology.

OBJECTIVE: The goal of this study was to describe clinical and neuroradiological features of arteriovenous malformations of the filum terminale (FT AVMs) and to present the authors' diagnostic and therapeutic management in this rare disease. METHODS: The presented cases were retrieved from a retrospectively collected database of all spinal vascular malformations treated between June 1992 and December 2021 at the Rheinisch-Westfälische Technische Hochschule (RWTH) University Hospital Aachen. Pretreatment and follow-up clinical and neuroradiological data were analyzed for this study. RESULTS: Data in 15 patients with FT AVM with a mean age of 60 years were included, with an overall incidence of FT AVM of 19% among all spinal AVMs in our cohort. Twelve of 15 (80%) patients were men. Nonspecific but typical clinical and MR findings of thoracolumbar congestive myelopathy were found in all patients. Spinal MR angiography, performed in 10 patients, identified in all cases the arterialized FT vein as well as a lumbar/lumbosacral location of an AV shunt. Digital subtraction angiography (DSA) showed an arterial supply solely via the FT artery in 12/15 (80%) patients and via an additional feeder from the lumbosacral region in the other 3/15 (20%) patients. All patients were treated surgically. During 1-year follow-up, 2 patients presented with recurrent FT AVM due to further arterial supply from the lumbosacral region, and were treated surgically. Neurological status was improved in all patients within the 1-year follow-up, with marginal further changes during long-term follow-up. CONCLUSIONS: Congestive myelopathy is the major pathological mechanism of symptoms in these patients, with no evidence for intradural bleeding. Missing the presence of possible multiple arterial supply of FT AVM during DSA may result in misdiagnosis and/or insufficient treatment. Due to the frequently prolonged course of FT artery, resection of the FT AVM may be a favorable treatment modality in comparison with endovascular treatment. Follow-up examinations are obligatory within the first 3 years after treatment, and further MR angiography and DSA examinations are indicated if congestive myelopathy persists.

The use of artificial intelligence and machine learning monitoring to safely administer a fluid-restrictive goal-directed treatment protocol to minimize the risk of transfusion during major spine surgery of a Jehovah's Witness: a case report.

BACKGROUND: The Hypotension Prediction Index (HPI) displays an innovative monitoring tool which predicts intraoperative hypotension before its onset. CASE PRESENTATION: We report the case of an 84-year-old Caucasian woman undergoing major spinal surgery with no possibility for the transfer of blood products given her status as a Jehovah's Witness. The hemodynamic treatment algorithm we employed was based on HPI and resulted in a high degree of hemodynamic stability during the surgical procedure. Further, the patient was not at risk for either hypo- or hypervolemia, conditions which might have caused dilution anemia. By using HPI as a tool for patient blood management, it was possible to reduce the incidence of intraoperative hypotension to a minimum. CONCLUSIONS: In sum, this HPI-based treatment algorithm represents a useful application for the treatment of complex anesthesia and perioperative patient blood management. It is a simple but powerful extension of standard monitoring for the prevention of intraoperative hypotension.

Clinical Outcome and Prognostic Factors of Patients with Perimesencephalic and Nonperimesencephalic Subarachnoid Hemorrhage.

OBJECTIVE: To demonstrate the clinical outcome of patients with nonperimesencephalic subarachnoid hemorrhage (npSAH) compared with patients with aneurysmal SAH (aSAH) and perimesencephalic SAH (pSAH) and to evaluate predictive value of various clinical and radiological findings in patients with npSAH. METHODS: We retrospectively identified patients with SAH who presented at our institution between 2009 and 2018. We analyzed demographic and clinical data and outcomes. Multivariable analysis was performed for outcome parameters. RESULTS: Of 608 patients with confirmed SAH, 78% had aSAH, and 22% had nonaneurysmal SAH. Nonaneurysmal SAH was perimesencephalic in 30% of cases and nonperimesencephalic in 70%. Initial clinical status (Hunt and Hess score) was significantly worse in patients with aSAH compared with patients with nonaneurysmal SAH. Complications such as delayed cerebral ischemia occurred significantly more often in patients with aSAH. Patients with pSAH had a more favorable clinical course than patients with aSAH or npSAH. There was no significant difference in 30-day mortality between aSAH (29%) and npSAH (28%) patients (P = 0.835). Hunt and Hess score emerged as a strong predictor of unfavorable outcome in both aSAH and npSAH in multivariable regression. CONCLUSIONS: Patients with npSAH had a similar clinical outcome as patients with aSAH, although there were significantly fewer clinical complications in patients with npSAH. Patients with pSAH demonstrated an overall good clinical course. Our multivariable analysis showed that initial Hunt and Hess score was an important predictor for clinical outcome in aSAH as well as npSAH.

Posterior reversible encephalopathy syndrome after induced hypertension therapy for delayed cerebral ischemia after subarachnoid hemorrhage: A case-control study.

BACKGROUND: Posterior reversible encephalopathy syndrome (PRES) is associated with arterial hypertension. Our aim was to investigate whether induced hypertension (IH) as therapy for delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH) is associated with PRES and to identify risk factors for PRES. MATERIAL AND METHODS: We retrospectively searched our database for patients with SAH and IH in our institution between 2009 and 2018 and identified additional cases of PRES after SAH with IH from the literature. We then analyzed demographic findings and clinical features of these patients. RESULTS: 172 patients with acute SAH received IH. PRES was diagnosed in 3/172 (1.7%) patients. Our literature search revealed 17 additional cases. The pooled PRES group (n = 20) was non-significantly older than the non-PRES group (n = 169) (median, 62.5 years vs. 52 years, p = 0.06). No significant differences were found between both groups with regard to sex (p = 0.73), Hunt & Hess-Score (p = 0.9), aneurysm treatment (p = 0.13), and time from diagnosis of SAH to the start of IH (p = 0.14). CONCLUSIONS: PRES after IH in SAH patients occurred in 1.7% of our patients. Our results imply that it is important to be aware of a possible development of a PRES in older SAH patients with IH, irrespective of sex, initial clinical status, and treatment modality.

Risk of postprocedural intracerebral hemorrhage in patients with ruptured cerebral aneurysms after treatment with antiplatelet agents.

OBJECTIVE: Endovascular treatment of ruptured cerebral aneurysms frequently requires antiplatelet medication to prevent thromboembolism. This might raise concern regarding the risk of postprocedural hemorrhage (pH), e.g. from placement of intracranial probes. We explored the risk of PH associated with standard antiplatelet therapy (sAP: acetylsalicylic acid, and/or clopidogrel) in the context of aneurysmal subarachnoid hemorrhage (aSAH). METHODS: We retrospectively reviewed a total of 146 consecutive cases with cerebral aneurysms treated between 1/2011-12/2015, and distinguished between minor (0.5 cm3) - 4 cm3) or major (> 4 cm3) PH occurring within four weeks after intervention. A separate analysis included hemorrhages related to placement of intracranial probes and drainages in the subgroup of 99 cases with such surgical interventions (pPH). Clinical outcome was assessed via Glasgow Outcome Scale (GOS) twelve months after aSAH. RESULTS: A total of 49 cases (33.6%) in the overall sample sustained PH, there were 19 cases of pPH. Multifactorial analyses yielded sAP as an independent predictor for minor, but not major PH (p < 0.001 vs. p = 0.829), with comparable results for pPH (p = 0.001 vs. p = 0.184). sAP did not influence the clinical outcome in either group. CONCLUSIONS: sAP was associated with a higher rate of minor PH and, more specifically, of minor pPH. However, it was neither accompanied by the occurrence of major hemorrhages nor by unfavorable clinical outcome. Future prospective studies should confirm these observations and hemorrhage risks associated with extended anticoagulation regimes after complex interventions and intra-arterial vasospasm therapy should be explored in order to facilitate interdisciplinary decision-making in aSAH.

Unique Angioarchitecture of Sacral Dural Arteriovenous Fistula.

BACKGROUND: Spinal dural arteriovenous fistulas (DAVFs) in the sacral region are extremely rare. The location and complex angioarchitecture of these lesions make both identification and treatment challenging, even in experienced hands. We report on a sacral DAVF with a unique angioarchitecture and discuss its specific anatomy. CASE DESCRIPTION: A 76-year-old male presented with progressive distal paraparesis and spinal ataxia. Three lumbar decompression surgeries were performed between 2016 and 2018 elsewhere on the basis of suspected degenerative lumbar syndrome. On admission to our center, the patient was wheelchair dependent due to extensive spinal ataxia associated with bilateral foot paresis and hypoesthesia. Spinal contrast-enhanced time-resolved magnetic resonance angiography and digital subtraction angiography were performed after admission to our center. Contrast-enhanced magnetic resonance angiography examinations suggested a sacral DAVF. Subsequent digital subtraction angiography demonstrated a spinal DAVF on the left side at the S2 vertebral level supplied via an arterial epidural branch from the right L4 segmental artery. The fistula was treated via surgical interruption of the proximal part of the radicular drainage vein. CONCLUSIONS: Sacral DAVFs present serious diagnostic difficulties and require a profound understanding of possible fistula-supplying arteries of the sacral region. Microsurgical interruption of the often ventrally located drainage vein presents an efficient treatment modality and could provide an immediate confirmation of fistula occlusion using indocyanine green videoangiography.

Anticoagulation Therapy After Surgical Treatment of Spinal Dural Arteriovenous Fistula. Effectiveness and Long-Term Outcome Analysis.

OBJECTIVE: Effectiveness and safety of anticoagulation therapy (AC) after treatment of spinal dural arteriovenous fistula (sdAVF) are still inadequately discussed in the literature and are addressed in this study. METHODS: We retrospectively analyzed our medical database for patients with sdAVF treated in our institution between 2006 and 2016. Neurologic status at time of admission, discharge, and last follow-up was assessed via Aminoff-Logue disability score. Patient cohorts were dichotomized as group A (postoperative therapeutic heparinization) and group B (routine thromboembolic prophylaxis with low-dose heparin). RESULTS: Fifty-three patients were included in this analysis. In group A (n = 11), no acute deterioration was reported. In group B (n = 42), 4 patients developed acute postoperative deterioration; therapeutic AC was initiated in all 4 patients resulting in complete neurologic recovery within the inpatient stay. However, the incidence of postoperative deterioration did not reach statistical significance between treatment groups (P = 0.57). Data of 40 patients were available for long-term analysis (mean, 53.4 ± 36 months). Neurologic status did not differ significantly between both groups at time of admission (P = 0.093), discharge (P = 0.723), and last follow-up (P = 0.222). CONCLUSIONS: Acute postoperative deterioration in patients with sdAVF is a clinically relevant complication and was present in 7.5% of patients in our series. Although routine therapeutic AC did not decrease the rate of acute deterioration significantly, our findings imply that therapeutic AC in cases of acute postoperative deterioration might be a safe and efficient treatment option.

Arterial Hypertension Is Associated with Symptomatic Spinal Dural Arteriovenous Fistulas.

OBJECTIVE: To determine possible systemic factors that may induce or be associated with the pathogenesis and pathologic course of spinal dural arteriovenous fistulas (SDAVFs), the most common type of arteriovenous disorder of the spinal cord and its meninges. METHODS: We assessed the role of possible systemic (vascular) risk factors (arterial hypertension, diabetes mellitus, fat metabolism disorders, and nicotine dependence) by comparing the prevalence of these risk factors in an SDAVF cohort of 59 patients with the prevalence in the general population. RESULTS: Age-corrected prevalence of arterial hypertension in the SDAVF cohort was significantly higher than in the general population (P < 0.001). Prevalence of diabetes mellitus (P = 0.150.), nicotine dependence (P = 0.561), adiposity (P = 0.217), and fat metabolism disorders (P = 0.125) did not differ from prevalence of comparable cohorts in the general population. CONCLUSIONS: Our results and data from the literature suggest that arterial hypertension may play an important role in the development of SDAVF-related symptoms or the development of SDAVFs in the presence of other predisposing factors.

Twist Drill Procedure for Chronic Subdural Hematoma Evacuation: An Analysis of Predictors for Treatment Success.

BACKGROUND: Twist drill craniostomy (TDC) is a minimally invasive and cost-effective technique to treat chronic subdural hematomas (CSDHs). Predictors for treatment success such as imaging characteristics, hematoma volume, and drainage volume are not established; thus, they are purpose of this analysis. MATERIAL AND METHODS: We retrospectively evaluated all data of patients with CSDH undergoing TDC in our institution between January 2010 and December 2013. We analyzed imaging characteristics (extension and composition), volumetrically calculated pre- and postoperative hematoma volumes, measured drainage volume, and clinical course. Primary treatment success was defined as sufficient if definitive treatment was achieved via a single TDC (TDC-1) and insufficient if more than one TDC was needed. The need for open surgical evacuation was defined as treatment failure. RESULTS: Data of 233 patients undergoing 387 TDCs were available for our study. A total of 67% of TDCs treated CSDHs effectively, whereas the remainder required further open surgical evacuation. Via use of the median-split-method, we found that sufficient treatment was achieved more frequently in smaller hematomas (P < 0.05). Treatment effectiveness was neither correlated with hematoma image characteristics (presence of membranes: P = 0.11, extent of chronification: P = 0.55) nor with the respective drainage volume (P = 0.95). Residual hematoma volume was consistently greater than expected by drainage calculation (P < 0.05). CONCLUSIONS: TDC is an effective treatment option for CSDH. Sufficient treatment with single TDC was more common in smaller hematomas with an associated smaller residual hematoma. Failure of brain re-expansion after TDC may increase the treatment failure rates. In these cases, an open surgical evacuation might accelerate treatment and clinical recovery.