Spine surgery in pregnant women: a multicenter case series and proposition of treatment algorithm.

PURPOSE: Spinal diseases requiring urgent surgical treatment are rare during pregnancy. Evidence is sparse and data are only available in the form of case reports. Our aim is to provide a comprehensive guide for spinal surgery on pregnant patients and highlight diagnostic and therapeutic aspects. METHODS: The study included a cohort of consecutive pregnant patients who underwent spinal surgery at five high-volume neurosurgical centers between 2010 and 2017. Perioperative and perinatal clinical data were derived from medical records. RESULTS: Twenty-four pregnant patients were included. Three underwent a preoperative cesarean section. Twenty-one patients underwent surgery during pregnancy. Median maternal age was 33 years, and median gestational age was 13 completed weeks. Indications were: lumbar disk prolapse (n = 14; including cauda equina, severe motor deficits or acute pain), unstable spine injuries (n = 4); intramedullary tumor with paraparesis (n = 1), infection (n = 1) and Schwann cell nerve root tumor presenting with high-grade paresis (n = 1). Two patients suffered transient gestational diabetes and 1 patient presented with vaginal bleeding without any signs of fetal complications. No miscarriages, stillbirths, or severe obstetric complications occurred until delivery. All patients improved neurologically after the surgery. CONCLUSION: Spinal surgical procedures during pregnancy seem to be safe. The indication for surgery has to be very strict and surgical procedures during pregnancy should be reserved for emergency cases. For pregnant patients, the surgical strategy should be individually tailored to the mother and the fetus.

Metabolic Parameters Influence Brain Infarction and Outcome after Resection of Brain Metastases.

Perioperative infarction in brain tumor surgery occurs in about 30-80% of cases and is strongly associated with poor patient outcomes and longer hospital stays. Risk factors contributing to postoperative brain infarction should be assessed. We retrospectively included all patients who underwent surgery for brain metastases between January 2015 and December 2017. Hemodynamic parameters were analyzed and then correlated to postoperative infarct volume and overall survival. Of 249 patients who underwent biopsy or resection of brain metastases during that time, we included 234 consecutive patients in this study. In total, 172/249 patients showed ischemic changes in postoperative magnet resonance imaging (MRI) (73%). Independent risk factors for postoperative brain infarction were perioperative blood loss (rho 0.189, p = 0.00587), blood glucose concentration (rho 0.206, p = 0.00358), blood lactate concentration (rho 0.176; p = 0.0136) and cumulative time of reduced PaCO2 (rho -0.142; p = 0.0445). Predictors for reduced overall survival were blood lactate (p = 0.007) and blood glucose levels (p = 0.032). Other hemodynamic parameters influenced neither infarct volume, nor overall survival. Intraoperative elevated lactate and glucose levels are independently associated with postoperative brain infarction in surgery of brain metastases. Furthermore, they might predict reduced overall survival after surgery. Blood loss during surgery also leads to more cerebral ischemic changes. Close perioperative monitoring of metabolism might reduce those complications.

Permutation entropy in intraoperative ECoG of brain tumour patients in awake tumour surgery- a robust parameter to separate consciousness from unconsciousness.

Awake craniotomies represent an essential opportunity in the case of lesions in eloquent areas. Thus, optimal surveillance of the patient during different stages of sedation, as well as the detection of seizure activity during brain surgery, remains difficult, as skin electrodes for electroencephalographic (EEG) analysis are not applicable in most cases. We assessed the applicability of ECoG to monitor different stages of sedation, as well as the influence of different patient characteristics, such as tumour volume, size, entity, and age or gender on permutation entropy (PeEn). We conducted retrospective analysis of the ECoG data of 16 patients, who underwent awake craniotomies because of left-sided brain tumours at our centre between 2014 and 2016. PeEn could be easily calculated and compared using frontal and parietal cortical electrodes. A comparison of PeEn scores showed significantly higher values in awake patients than in patients under anaesthesia (p ≤ 0.004) and significantly higher ones in the state of transition than under general anaesthesia (p = 0.023). PeEn scores in frontal and parietal leads did not differ significantly, making them both applicable for continuous surveillance during brain surgery. None of the following clinical characteristics showed significant correlation with PeEn scores: tumour volume, WHO grade, first or recurrent tumour, gender, and sex. Being 50 years or older led to significantly lower values in parietal leads but not in frontal leads. ECoG and a consecutive analysis of PeEn are feasible and suitable for the continuous surveillance of patients during awake craniotomies. Hence, the analysis is not influenced by patients' clinical characteristics.

Impact of ischemic preconditioning on surgical treatment of brain tumors: a single-center, randomized, double-blind, controlled trial.

BACKGROUND: Postoperative ischemia is a frequent phenomenon in patients with brain tumors and is associated with postoperative neurological deficits and impaired overall survival. Particularly in the field of cardiac and vascular surgery, the application of a brief ischemic stimulus not only in the target organ but also in remote tissues can prevent subsequent ischemic damage. We hypothesized that remote ischemic preconditioning (rIPC) in patients with brain tumors undergoing elective surgical resection reduces the incidence of postoperative ischemic tissue damage and its consequences. METHODS: Sixty patients were randomly assigned to two groups, with 1:1 allocation, stratified by tumor type (glioma or metastasis) and previous treatment with radiotherapy. rIPC was induced by inflating a blood pressure cuff placed on the upper arm three times for 5 min at 200 mmHg in the treatment group after induction of anesthesia. Between the cycles, the blood pressure cuff was released to allow reperfusion. In the control group no preconditioning was performed. Early postoperative magnetic resonance images (within 72 h after surgery) were evaluated by a neuroradiologist blinded to randomization for the presence of ischemia and its volume. RESULTS: Fifty-eight of the 60 patients were assessed for occurrence of postoperative ischemia. Of these 58 patients, 44 had new postoperative ischemic lesions. The incidence of new postoperative ischemic lesions was significantly higher in the control group (27/31) than in the rIPC group (17/27) (p = 0.03). The median infarct volume was 0.36 cm3 (interquartile range (IR): 0.0-2.35) in the rIPC group compared with 1.30 cm3 (IR: 0.29-3.66) in the control group (p = 0.09). CONCLUSIONS: Application of rIPC was associated with reduced incidence of postoperative ischemic tissue damage in patients undergoing elective brain tumor surgery. This is the first study indicating a benefit of rIPC in brain tumor surgery. TRIAL REGISTRATION: German Clinical Trials Register, DRKS00010409 . Retrospectively registered on 13 October 2016.

Safe Brain Tumor Resection Does not Depend on Surgery Alone - Role of Hemodynamics.

Aim of this study was to determine if perioperative hemodynamics have an impact on perioperative infarct volume and patients' prognosis. 201 cases with surgery for a newly diagnosed or recurrent glioblastoma were retrospectively analyzed. Clinical data and perioperative hemodynamic parameters, blood tests and time of surgery were recorded. Postoperative infarct volume was quantitatively assessed by semiautomatic segmentation. Mean diastolic blood pressure (dBP) during surgery (rho -0.239, 95% CI -0.11 - -0.367, p = 0.017), liquid balance (rho 0.236, 95% CI 0.1-0.373, p = 0.017) and mean arterial pressure (MAP) during surgery (rho -0.206, 95% CI -0.07 - -0.34, p = 0.041) showed significant correlation to infarct volume. A rank regression model including also age and recurrent surgery as possible confounders revealed mean intraoperative dBP, liquid balance and length of surgery as independent factors for infarct volume. Univariate survival analysis showed mean intraoperative dBP and MAP as significant prognostic factors, length of surgery also remained as significant prognostic factor in a multivariate model. Perioperative close anesthesiologic monitoring of blood pressure and liquid balance is of high significance during brain tumor surgery and should be performed to prevent or minimize perioperative infarctions and to prolong survival.