The Fisher Scale grades subarachnoid haemorrhage on CT to predict vasospasm risk: Grade 0 (no blood), Grade 1 (thin SAH), Grade 2 (thin SAH + IVH), Grade 3 (thick SAH), Grade 4 (thick SAH + IVH). Modified Fisher Scale is preferred. Anaesthesia trainees use it to guide monitoring, vasospasm surveillance, and ICU triage.
The WFNS Scale grades subarachnoid haemorrhage using GCS (3-15) and motor deficit presence. Grade I (GCS 15, no deficit) to Grade V (GCS 3-6). It offers superior objectivity and prognostic accuracy over Hunt & Hess. Anaesthesia trainees use it to guide airway planning, monitoring intensity, and postoperative ICU destination in neurocritical care.
Tactile evaluation of the train-of-four is unreliable—fade is undetectable until the ratio falls below 0.4. Quantitative monitors provide a numeric TOF ratio, enabling objective assessment. Residual paralysis (TOF < 0.9) occurs in 30–40% of PACU patients when relying on qualitative PNS alone. Upgrade your practice. Protect your patients.
The Peripheral Nerve Stimulator (PNS) is essential for safely managing neuromuscular blocking agents. It quantifies twitch response to guide intubation, redosing, and reversal. Avoid reliance on tactile assessment alone—residual paralysis is often missed. Master PNS patterns (TOF, tetanus, PTC) to prevent PACU complications and improve patient outcomes.
The CO₂ absorber is the chemical device that removes this exhaled CO₂, allowing for low fresh gas flow (FGF) anesthesia. By scrubbing CO₂, it enables rebreathing of oxygen, volatile anesthetics, and inert carrier gases—conserving heat, humidity, and costly agents.
