Title : A significance of inspiratory muscle strength in gynaecologic patients after spinal anaesthesia
Background and Goal of Study: Spinal block, a method to provide anesthetics intrathecally, is a favorable technique in patients with difficult ventilation difficult intubation, or irritable airways. However, spinal anesthesia is not without adverse effects. Generally, it results in mild hypotension, weakness of diaphragm and respiratory muscles as well as cough impairment in a period of time. Apparently, the ventilatory impairment varies to the level of sympathetic blockage. Investigators are curious about the facility of Mini Wright Peak Flow Meter to assess patient’s respiratory function pre and post spinal anesthesia. Whether or not the peak expiratory flow rate (PEFR) is related to the level of sympathetic blockage? Is it possible to predict the respiratory outcome after the maneuver? This prospective study, scheduled from April to September 2018, has been approved by Siriraj Institutional Review Board (COA: Si108/2018) and registered via Thai Clinical Trials Registry (TCTR20180921002). The inclusion criteria were Gynecologic patients undergoing elective exploratomy laparotomy under spinal anesthesia, aged 18-65 years, ASA class I-II. The exclusion criteria were patients with BMI>30 kg/sqm, history of severe medical diseases, abnormal chest wall, kypho-scoliosis, using anti-psychotic or sedative drug, as well as pregnancy. As a result, investigators would like to study the relationship between anesthetic level and peak expiratory flow rate.
Take Away Notes:
• MiniWright Peak Flow Meter, a bedside instrument, is easy to assess patient in term of breathing exercise, and coughing in particular
• Regional anesthesia has effects on patient’s sympathetic outflow resulting in not only sensory and motor blockage but also vasodilatation and respiratory function impairment
• Investigators would like to use MiniWright Peak Flow Meter to evaluate patient undergoing spinal anaesthesia for gynecologic surgery