Adrenal Gland Neoplasms/surgery; Anesthesia, Epidural; Anesthesia, General/methods; Hypertension/etiology; Intraoperative Complications/etiology; Neoplasms, Multiple Primary/surgery; Pheochromocytoma/surgery; Pregnancy Complications, Neoplastic/surgery; Pregnancy Trimester, Second; Tachycardia/etiology; Adrenal Gland Neoplasms/complications; Adrenal Gland Neoplasms/diagnosis; Adrenergic alpha-Antagonists/administration & dosage; Adrenergic alpha-Antagonists/therapeutic use; Adult; Anesthetics, General/administration & dosage; Anesthetics, Local/administration & dosage; Female; Humans; Hypertension/drug therapy; Intraoperative Complications/drug therapy; Labetalol/therapeutic use; Laparotomy; Neoplasms, Multiple Primary/complications; Neoplasms, Multiple Primary/diagnosis; Pheochromocytoma/complications; Pheochromocytoma/diagnosis; Preanesthetic Medication; Pregnancy; Pregnancy Complications, Cardiovascular/drug therapy; Pregnancy Complications, Cardiovascular/etiology; Tachycardia/drug therapy