Focused Feedback

MAC Check is a self-paced, dynamic online platform that uses a longitudinal assessment approach and offers immediate, ongoing feedback after each question, including supporting rationale for correct and incorrect answers. The focused feedback webpage offers insight and distillation for topics within MAC Check that are commonly marked as incorrect, while also providing practical steps on how CRNAs can implement best practices. 

The Sitting Position in Anesthesia – Protecting Cerebral Perfusion 

  • Use an arterial line transduced at the tragus to accurately monitor cerebral perfusion pressure (CPP) and adjust vasopressor support as needed. Non-invasive blood pressure (NIBP) measurements at the arm underestimate brain perfusion in this position. 

  • To reduce the risk of venous air embolism (VAE), maintain adequate venous pressure by ensuring proper hydration, using PEEP cautiously, and positioning the head lower than the heart when feasible. Consider precordial Doppler for high-risk cases. 

Long-Standing Diabetes and Perioperative Management

  • Avoid aggressive glucose correction intraoperatively. Maintain blood glucose between 140-180 mg/dL to reduce the risk of perioperative hypoglycemia and hyperglycemia-induced complications (e.g., infection, poor wound healing). Insulin infusions are preferred over sliding-scale insulin alone for tight control in high-risk cases. 
  • Screen for autonomic dysfunction preoperatively. Long-standing diabetes increases the risk of silent myocardial ischemia, gastroparesis, and intraoperative hemodynamic instability. Perform a thorough cardiac risk assessment and consider minimizing anesthetic agents that blunt compensatory sympathetic responses (e.g., high-dose volatile anesthetics, rapid induction with propofol). 

Preventing Perioperative Hypothermia and Combating Redistribution Hypothermia 

  • Pre-warm patients for at least 30 minutes before induction using forced-air warming blankets or warmed IV fluids. This reduces the impact of redistribution hypothermia, which occurs in the first hour after induction due to vasodilation and core-to-peripheral heat transfer. 
  • Use a multimodal warming approach intraoperatively, including active forced-air warming, warmed IV fluids (>37°C), and minimizing heat loss with draping strategies. Passive warming alone (e.g., blankets) is insufficient to maintain normothermia during prolonged procedures. 

Myasthenia Gravis and Anesthesia – Risk Recognition and Management

  • Assess risk for postoperative respiratory failure using the 'TOO WEAK' tool (high pyridostigmine dose, long disease duration, bulbar involvement, low vital capacity, emergency surgery, age >50, prior intubation issues). High-risk patients should have an ICU plan for extubation readiness. 
  • Minimize neuromuscular blocking agents (NMBAs)—use 1/10th the usual dose of non-depolarizing agents if required, with quantitative TOF monitoring. Consider volatile anesthetics, propofol, or remifentanil-based techniques for relaxation. 

Essential Monitoring in General Anesthesia (Standard V – Scope & Standards for Nurse Anesthesia Practice)

  • Continuously Monitor These Four Key Parameters: 
      1. Oxygenation: Pulse oximetry and FiO₂ verification. 
      2. Ventilation: End-tidal CO₂ (ETCO₂) to confirm adequate ventilation. 
      3. Circulation: ECG and blood pressure (at least every 5 minutes). 
      4. Temperature: Monitor for hypothermia in prolonged cases. 
  • Use Multimodal Monitoring to Optimize Patient Safety: 
      - Capnography detects apnea before hypoxia develops. 
      - Invasive monitoring may be needed for high-risk cases. 
      - Neuromuscular monitoring prevents residual paralysis.