Use of Classic LMA During Endovascular Therapy

Objective

• To assess the usefulness of general anesthesia with Laryngeal Mask Airway (LMA)-Classic for the endovascular treatment of cerebral aneurysms based on cardiovascular stability analysis Data collection Anesthetic protocol was standardized for all patients consisting of an intravenous induction with fentanyl (1-2 μg/kg), lidocaine (1.5 mg/kg), propofol (2 mg/kg), and dexamethasone (8 mg) followed by the insertion of the LMA-Classic. Sevoflurane with a minimal alveolar concentration (MAC) between 0.9 and 1.1%, dipyrone (2 gr IV), and morphine (0.05 mg/kg IV) were used during maintenance. Tidal volume (VT) and respiratory rate (RR) were adjusted to 7 ml/Kg and 12-14 per minute respectively. Non-invasive hemodynamic monitoring included mean arterial pressure (MAP), heart rate (HR), oxygen saturation, and end-tidal carbon dioxide (ETCO2).

Data was collected within six time points: Time point 1: before induction, Time point 2: after induction, Time point 3: after LMA-Classic insertion, Time point 4: during the endovascular procedure, Time point 5: during coiling, and Time point 6: at the end of the procedure and LMA-Classic removal.

The following demographic and clinical data were collected: age, gender, American Society of Anesthesiologists Physical Status (ASA-PS), total procedure time, comorbidities, aneurysm location, and associated clinical manifestations. Adverse events, such as intraoperative aneurysm rupture or need for endotracheal intubation, will be recorded.

Ethical considerations Approvals were obtained from the ethics committees at Antioquia University and Especialidades Médicas Metropolitanas Sociedad Anónima (EMMSA) Clinic. Patients signed an informed consent and confidentiality agreement before participating.

Statistical analysis Data was collected in an excel spreadsheet (Microsoft Excel 2010®), SAS 9.4 (SAS Institute, Cary, N.C.) was used for subsequent analysis. Continuous variables were summarized as means and standard deviations (SD). Categorical variables were summarized as frequencies and percentages. Linear mixed models were fit to model continuous clinical variables over time using contrasts to test differences between time points. P-values less than 0.05 were considered to be statistically significant.

Inclusion criteria

• Patients ≥ 18 years old
• Diagnosed with an unruptured cerebral aneurysm or SAH (Hunt & Hess grade I or II)
• Planned to undergo endovascular therapy under general anesthesia between April 2015 and February 2017 in the Especialidades Médicas Metropolitanas Sociedad Anónima (EMMSA) Clinic in Bello, Antioquia, Colombia

Exclusion criteria

• Patients diagnosed with a cerebral aneurysm undergoing craniotomy and clipping and patients with SAH (Hunt & Hess grade > II).