Guidelines for Safe Spinal Anaesthesia

Pre‑procedure Assessment

Rule out absolute contraindications – patient refusal, coagulopathy or active anticoagulation must be excluded before proceeding. 1
Platelet count threshold – a platelet count of ≥75 × 10⁹ L⁻¹ is considered safe for spinal anaesthesia in patients with suspected thrombocytopenia. 2
Factor level requirements for haemophilia – maintain Factor VIII or IX ≥50 IU dL⁻¹ for a mild bleeding history and ≥80 IU dL⁻¹ for a severe history. 1
Minimum fibrinogen level – fibrinogen ≥1.5 g L⁻¹ (Clauss method) is acceptable for performing spinal anaesthesia in hypofibrinogenemic patients. 1
Intravenous fluid limitation – limit crystalloid administration to ≤500 mL before the block to reduce the risk of postoperative urinary retention. 3

Pencil‑point needles ≥25 G – using these needles lowers the incidence of post‑dural puncture headache (PDPH) to <1 %. 4
Avoid cutting‑bevel needles – cutting‑bevel designs significantly increase PDPH risk (American Society of Anesthesiologists recommendation). 5
Maintain aseptic technique – standard aseptic preparation and draping are sufficient for uncomplicated patients. 6

Sitting position for perianal/perineal surgery – this position helps minimise hypotension and motor block. 4
Lateral decubitus for unilateral procedures – placing the operative side down targets the block effectively. 4

Identify the lumbar interspace – the usual insertion sites are L3‑4 or L4‑5. 1
Insert a ≥25 G pencil‑point needle – the needle may be introduced via a midline or paramedian approach. 3
Confirm free flow of clear cerebrospinal fluid before drug injection. 1
Inject the calculated dose of local anaesthetic slowly to ensure even distribution. 4

Treat hypotension promptly – monitor blood pressure continuously and use vasopressors when needed. 2
Do not force oral intake post‑operatively – early oral intake may provoke nausea and delay discharge. 3

Mobilisation criteria – patients should have return of perianal sensation (S4‑5 dermatomes) and plantar‑flexion strength comparable to pre‑operative levels before ambulation. 3
Proprioception recovery – return of proprioception in the big toe is required before full discharge. 7
Discharge with residual sensory block – permissible if the limb is protected and adequate home support is arranged. 7
Provide written and verbal instructions about expected block duration and PDPH warning signs. 7
Driving and alcohol restrictions – advise patients to avoid driving, operating machinery, or consuming alcohol for 24 hours after the block. 3
Warning signs and emergency contacts – give patients clear information on signs of complications and how to obtain urgent help. 3
Prophylactic antiemetics – reserve anti‑emetic prophylaxis for patients at high risk of postoperative nausea and vomiting (e.g., prior PONV, motion sickness, laparoscopic procedures). 4
NSAID prophylaxis – administer a long‑acting NSAID pre‑emptively unless contraindicated. 4
Limit routine opioid use – avoid routine morphine administration to reduce the incidence of postoperative nausea and vomiting. 4

Establish intravenous access before initiating spinal anaesthesia – recommended by the American Society of Anesthesiologists to ensure safe drug delivery and monitoring. 8
Do not administer a routine fixed‑volume crystalloid bolus before the block – the American Society of Anesthesiologists advises against a standard bolus to avoid unnecessary fluid overload. 8

Consider routine aspiration prophylaxis for obstetric patients and anyone at high risk of pulmonary aspiration – a precaution endorsed by the American Society of Anesthesiologists. 9

Use ≥25‑gauge pencil‑point (Whitacre or Sprotte) needles for spinal puncture – this needle type reduces the incidence of post‑dural puncture headache (PDPH) to less than 1 %. 8
Avoid cutting‑bevel needles – cutting needles significantly increase the risk of PDPH compared with pencil‑point designs. 8

Sitting position for perianal or perineal surgery – this position minimizes intra‑operative hypotension and motor block in these procedures. 10
Lateral decubitus with the operative side down for unilateral lower‑extremity surgery (e.g., knee arthroscopy) – optimizes block distribution to the target limb. 10

Require return of perianal (S4‑5) sensation before allowing ambulation – a safety check to ensure adequate sensory recovery. 10
Require plantar‑flexion strength comparable to pre‑operative levels before ambulation – confirms sufficient motor recovery. 10
Require return of proprioception in the big toe before ambulation – ensures protective sensation is restored. 10
Patients may be discharged with residual sensory or motor block if the limb is protected and adequate home support is arranged – the Anaesthesia guideline permits discharge under these conditions. 10
Provide written and verbal instructions about expected block duration and warning signs of PDPH – essential for safe post‑discharge care. 10
Include clear guidance on actions to take if a post‑dural puncture headache develops – facilitates timely management. 10
Implement a postoperative analgesic plan that includes a long‑acting NSAID (unless contraindicated) and oral analgesics, with instructions for when the block resolves – recommended to control pain while minimizing opioid‑related side effects. 10