1. Criteria and Protocols for Weaning and Discontinuation

Safe discontinuation of extracorporeal modalities hinges on confirming toxin clearance and clinical recovery amid vigilant monitoring for rebound toxicity. This process requires a structured approach with clear endpoints and fail-safes.

A. Toxin Clearance Endpoints

The primary goal is to ensure the offending substance has been adequately removed. Target values are toxin-specific and must be sustained.

• Specific Targets: Examples include serum methanol <20 mg/dL, lactate <2 mmol/L, normalization of the anion gap, and a sustained pH ≥7.30.
• Confirmation: Require at least two consecutive measurements over a 6 to 12-hour period without an upward trend to confirm sustained clearance.

B. Clinical Improvement Markers

Laboratory data must be paired with clinical signs of recovery.

• Hemodynamics: Mean arterial pressure (MAP) ≥65 mm Hg off vasopressors, or a vasopressor dose reduction of ≥50% over 12 hours.
• Mental Status: Return of purposeful movement and coherent speech or orientation.

C. Stepwise De-escalation Protocol

A gradual reduction in support allows for safe assessment of the patient’s tolerance.

1. Reduce blood flow rate by 20–30% every 4–6 hours.
2. After 1–2 successful blood flow reductions, decrease dialysate or replacement fluid flow by 25%.
3. Monitor labs (e.g., lactate, pH) and vital signs before each step.
4. Cease therapy once minimal flows are tolerated and clinical/lab endpoints are met.

D. Escalation Triggers and Fail-safes

Immediate action is required if the patient shows signs of decompensation.

• Rebound Toxicity: A rebound in lactate to >2 mmol/L or a drop in pH to <7.30.
• Hemodynamic Instability: New-onset hypotension requiring vasopressor initiation/escalation or new significant arrhythmias.
• Action: If a trigger occurs, revert to the prior successful settings immediately and repeat toxin assays every 2 hours.

2. Transitioning to Enteral Pharmacotherapy

Converting from intravenous to enteral medications reduces line-related risks and facilitates patient mobility, but it demands a careful assessment of gastrointestinal (GI) function, appropriate formulation selection, and diligent pharmacokinetic and pharmacodynamic monitoring.

A. Assessing Gastrointestinal Readiness

Before any transition, GI function must be confirmed to ensure adequate drug absorption.

• Clinical Signs: Presence of bowel sounds, minimal gastric residual volumes (<200 mL), and no significant abdominal distension or signs of ileus.
• Functional Marker: The ability to tolerate trophic enteral nutrition feeds is a good indicator of adequate gut mucosal perfusion and function.

B. Dosing, Titration, and Monitoring Examples

Initiating oral therapy often requires dose adjustments and close monitoring. Therapeutic drug monitoring (TDM) is crucial for narrow therapeutic index agents.

3. Prevention and Management of Post-ICU Syndrome (PICS)

Post-ICU Syndrome (PICS) is a constellation of physical, cognitive, and psychiatric impairments that persist after critical illness. Proactive, multidisciplinary strategies are essential to reduce its incidence and severity.

A. Identifying High-Risk Patients

Certain factors increase the likelihood of developing PICS:

• Age >65 years
• Pre-existing comorbidities (e.g., frailty, cognitive impairment)
• Duration of sedation >48 hours
• Duration of mechanical ventilation >7 days
• Presence of delirium during the ICU stay

4. Medication Reconciliation and Discharge Counseling

A structured reconciliation and counseling process at ICU and hospital discharge is critical to ensure continuity of care, prevent medication errors, and avoid accidental toxin re-exposure.

A. Comprehensive Medication Review

• Reconciliation: Meticulously compare pre-ICU home medications with the current ICU regimen and the planned discharge list. Systematically resume chronic therapies that were paused during critical illness.
• Dose Adjustments: Verify current renal and hepatic function and adjust all medication doses accordingly before discharge.

B. Patient Education and Adherence Tools

• Medication List: Provide a clear, reconciled, and preferably color-coded medication list that specifies each drug’s purpose, dose, schedule, and key monitoring parameters.
• Checklists: Use patient and caregiver-friendly checklists to reinforce adherence strategies and teach them how to recognize common or serious adverse effects.

C. Follow-up and Toxin Avoidance

• Monitoring Plan: Schedule necessary laboratory follow-up within 7 days of discharge, especially for serum creatinine and drug levels for narrow-TI agents.
• Referrals: Arrange timely referrals to relevant specialists, such as nephrology, toxicology, or psychiatry, as needed.
• Toxin Counseling: For patients recovering from poisoning, provide explicit counseling on environmental risks and strategies to avoid re-exposure (e.g., safe storage and handling of antifreeze after ethylene glycol poisoning).