Debriefing in Post-Resuscitation Care and Emergency Management: Role, Structure, and Purpose

MD Anaesthesia | Distinction-Level Theory Answer

1. INTRODUCTION AND DEFINITION

Examiner Pearl: The examiner will test whether the candidate knows that debriefing serves a dual mandate - quality improvement and psychological healing - and whether they can describe the two distinct temporal forms: the immediate informal huddle and the delayed formal session.

2. TYPES OF DEBRIEFING: CLASSIFICATION BY TIMING AND STRUCTURE

• Tintinalli's Emergency Medicine: "Critical incident stress debriefing can reduce the psychological impact of these events on medical responders and offer immediate emotional support to healthcare workers. Data from previous experiences suggest that such intervention can assist providers in maintaining job performance and satisfaction, resulting in improved patient care." (Tintinalli, Ch. 1)
• Sabiston Textbook of Surgery: "After disposition of the patient, scheduled structured debriefing sessions aid leaders and followers in professional development. Focus of these sessions is on team factors and must avoid personal accusations." (Sabiston, Ch. 36)

3. WHO SHOULD ORGANISE AND ATTEND

DEBRIEF ORGANISATION FRAMEWORK
┌───────────────────────────────────────────────────────────────┐
│  ORGANISER: Senior Intensivist (e.g., Obstetric Intensivist)  │
│  ± Anaesthesia Consultant ± Medical/Obstetric Consultant       │
└──────────────────────┬────────────────────────────────────────┘
                       │
            ┌──────────▼──────────────┐
            │  MANDATORY ATTENDEES    │
            │  All staff who were     │
            │  present during event:  │
            │  - Anaesthetists        │
            │  - Obstetricians        │
            │  - Intensivists         │
            │  - Midwives/Nurses      │
            │  - OT Technicians       │
            │  - Residents/Trainees   │
            │  - Non-clinical staff   │
            └─────────────────────────┘

4. STRUCTURE OF THE FORMAL DEBRIEFING SESSION

A. The After-Action Report (AAR) Framework

"The AAR should focus on gathering input in two categories: things that went well or worked and things that did not work or need to be improved... This should be done in an entirely nonjudgmental and nonpunitive manner, and input from all levels should be encouraged." - Sabiston Textbook of Surgery, Ch. 36 (Disaster Management)

"The AAR should be completed as soon after the event as possible to capture events while they are fresh in people's minds and ensure maximal participation." - Sabiston, Ch. 36

B. Structured Communication Tools Used During Debriefing

C. Debriefing Models Referenced in Anaesthesia Literature

From Miller's Anesthesia: "Although debriefing is uniformly viewed as essential to health care team simulation effectiveness and structured debriefing models are frequently cited as highly effective, there is no consensus on which specific methods, including video review debriefings, represent best practices. Quality of implementation is consistently cited as the most important contributing factor to effectiveness of debriefing." (Miller's Anesthesia, 10e, Ch. 5)

5. GOALS AND BENEFITS OF DEBRIEFING

A. Quality Improvement and Systems Learning

SYSTEMS LEARNING CYCLE
                     ┌─────────────────┐
                     │  Critical Event  │
                     └────────┬─────────┘
                              │
                    ┌─────────▼──────────┐
                    │ Immediate Huddle    │
                    │ (Hot Debrief)       │
                    │ Quick written note  │
                    └─────────┬──────────┘
                              │
                    ┌─────────▼──────────┐
                    │ Formal Debrief      │
                    │ (Cold Debrief)      │
                    │ AAR + Action Plan   │
                    └─────────┬──────────┘
                              │
              ┌───────────────▼───────────────────┐
              │      LEARNING HEALTH SYSTEM        │
              │   - Protocol updates               │
              │   - Equipment changes              │
              │   - Team retraining                │
              │   - Simulation drills              │
              │   - Policy amendments              │
              └───────────────────────────────────┘

1. Identify performance gaps - systematic identification of what went well, what went poorly, and what specific actions can be taken to improve future care
2. Reinforce correct behaviours - the debriefing is "where learning points are reinforced and progress towards desired knowledge, attitudes, and behavior can be developed" (Schwartz's Principles of Surgery, 11e)
3. Foster self-reflection - provides "opportunity to observe their performance and provide discussion of the strengths, weaknesses, and opportunities for improvement... in a non-judgmental, but constructive manner" (Miller's Anesthesia, 10e)
4. Scientific understanding - enhances evidence-based understanding of event pathophysiology and team dynamics
5. System-level change - identifies "latent threats" - system errors that would cause harm during actual patient encounters, discovered in in situ simulation (Miller's Anesthesia, 10e)
6. Improve decision-making - "Debriefing, after-action reflection, and metacognition can all create awareness around compromised decision-making" (Miller's Anesthesia, 10e, System Strategies)

B. Optimising Team Performance and Non-Technical Skills

• Have strong content knowledge
• Be cognisant of keeping the environment learner-centric
• Identify gaps between observed and desired performance
• Create psychological safety - defined as a non-threatening, open environment
• Possess conflict management and resolution skills
• Address strong learner emotions directly

"Debriefing faculty should be comfortable with skills that include postsimulation facilitation, creating psychological safety, and conflict management/resolution." - Sabiston Textbook of Surgery, Ch. 1

C. Psychological Support and Healing

• Acute anxiety and emotional shock
• Guilt, self-blame, and professional doubt
• Post-traumatic stress disorder (PTSD)
• Burnout and compassion fatigue
• Deteriorating job performance and satisfaction

Critical Examiner Pearl - The Paradox of Psychological Debriefing:

There is an important distinction that examiners may probe: "Critical Incident Stress Debriefing" (CISD, used in emergency/disaster settings) is different from "Psychological Debriefing" as studied in the trauma-psychiatry literature. Kaplan & Sadock's Comprehensive Textbook of Psychiatry explicitly states: "well-conducted studies showed no evidence of beneficial effects and even suggested that debriefing may have a negative effect on recovery. After a negative Cochrane review first published in 1997, most treatment guidelines have been updated to recommend against providing psychological debriefing on a routine basis for adults after trauma." However, within the context of clinical team debriefing post-resuscitation, the CISD framework and structured team debriefs serve an important recognitional and supportive function, and do not aim to be therapeutic in the narrow psychological sense. They facilitate acknowledgement of distress and appropriate onward referral.

6. THE OBSTETRIC CONTEXT: MATERNAL CARDIAC ARREST

1. It involves a "bundled" multi-disciplinary team with distinct communication challenges
2. The event is extremely rare, making real-world learning opportunities scarce and simulation imperative
3. The stakes involve two lives - mother and neonate - amplifying emotional impact on all staff
4. Near-simultaneous decision-making (CPR quality vs. perimortem CS vs. transfer) creates multiple potential debriefable moments
5. Quality of CPR during transfer is significantly impaired (interruptions in 92% of transfers during simulated maternal cardiac arrest - Creasy & Resnik, 7e), making system-level debrief and protocol review essential

7. ELEMENTS OF A DISTINCTION-LEVEL DEBRIEF SESSION: PRACTICAL FLOWCHART

POST-CRITICAL EVENT DEBRIEFING PROTOCOL
═══════════════════════════════════════════════════════════

PHASE 1: IMMEDIATE HUDDLE (Within minutes of event)
─────────────────────────────────────────────────────
 • Assemble all available team members at bedside
 • Team leader facilitates (2-5 min)
 • "What just happened?" - brief chronological recap
 • Acknowledge emotional reactions verbally
 • Generate QUICK WRITTEN NOTE (contemporaneous record)
 • Plan for formal debrief - set date/time/venue

PHASE 2: LOGISTICAL ORGANISATION (Within 24-48 hours)
──────────────────────────────────────────────────────
 • Senior intensivist (obstetric) organises session
 • Invite ALL involved staff (mandatory attendance)
 • Relevant consultants: anaesthesia, OB, neonatology
 • Gather: event record, monitoring data, video if available
 • Prepare structured agenda

PHASE 3: FORMAL DEBRIEFING SESSION (48 hours - 2 weeks)
────────────────────────────────────────────────────────
 OPENING (5-10 min)
   ├── Ground rules: non-judgmental, no blame, confidential
   ├── Establish psychological safety
   └── Define purpose: learning + support

 EVENT RECONSTRUCTION (10-20 min)
   ├── Chronological re-narration
   ├── Each team member's perspective invited
   └── Clarify timeline and sequence of decisions

 PERFORMANCE REVIEW (20-30 min)
   ├── What went well? (start here - positive first)
   ├── What could have been improved?
   ├── Protocol adherence / deviations
   ├── Communication issues (CRM failures)
   ├── Equipment/system failures
   └── Near-misses identified

 PSYCHOLOGICAL CHECK-IN (10-15 min)
   ├── Normalise distress responses
   ├── "How is everyone feeling?"
   ├── Acknowledge grief, guilt, shock
   └── Identify individuals needing onward referral

 ACTION PLANNING (10-15 min)
   ├── Specific actionable improvements listed
   ├── Assign responsibility + deadline
   ├── Schedule follow-up simulation if needed
   └── Document in formal AAR

 CLOSING
   ├── Summarise key learning points
   ├── Thank all participants
   └── Signpost: employee assistance / psychology referral

═══════════════════════════════════════════════════════════

8. QUALITY IMPROVEMENT OUTPUT: THE AFTER-ACTION REPORT (AAR)

• Completed as soon as possible post-event
• Conducted at every level: department (ED, ICU, OT) up to facility and system level
• Non-judgmental, non-punitive
• Captures input from ALL levels of the team
• Formal written report submitted up the chain of command
• Generates a specific action plan with prioritised changes

"Institutionalization of processes like this, with the aim of continual improvement of the delivery of care and focused on the patient at the center, characterise the 'Learning Health System.'" - Sabiston Textbook of Surgery, Ch. 36

9. ROLE OF SIMULATION IN DEBRIEF CULTURE

"The debriefing environment and discussion ought to be open, nonjudgmental, and directed at improvement in individual and overall team performance. A facilitator with strong content knowledge should ensure that the discussion includes identification of gaps between the observed and desired performance." - Schwartz's Principles of Surgery, 11e

10. GAP CHECK AND EXAMINER PEARLS

11. CONCLUSION

Sources Cited

• Miller's Anesthesia, 10e - Chs. 5 (Briefings and Debriefings, Debriefing and Feedback, System Strategies, Patient Simulation for System Evaluation)
• Barash, Cullen, and Stoelting's Clinical Anesthesia, 9e - Ch. 14 (Maternal Cardiac Arrest)
• Schwartz's Principles of Surgery, 11e - Ch. 23 (Principles of Team-Based Health Care, Postsimulation Debriefing)
• Sabiston Textbook of Surgery, 20e - Ch. 1 (Effective Uses of Simulation for Training, Debriefing Faculty), Ch. 36 (Debrief, Trauma Resuscitation), Ch. 36/11 (Postevent Processing and Improvement, After-Action Reports)
• Tintinalli's Emergency Medicine, 9e - Ch. 1 (Mental Health, Terminating Disaster Response, Critical Incident Stress Debriefing, After-Action Reports)
• Kaplan & Sadock's Comprehensive Textbook of Psychiatry, 12e - Ch. 26 (Early Psychological Interventions, Psychological Debriefing - evidence against routine use)
• Fuster and Hurst's The Heart, 15e - Ch. 21 (Cardiopulmonary Resuscitation during Pregnancy)
• Creasy & Resnik's Maternal-Fetal Medicine, 8e - Ch. 18 (Maternal Cardiac Arrest - CPR quality during transfer)

One-Lung Ventilation (OLV)

MD Anaesthesia | Distinction-Level Theory Answer

1. INTRODUCTION

Examiner Pearl: The examiner expects the candidate to know the critical distinction between lung isolation (protecting a healthy lung from contamination - DLT mandatory) and lung separation (surgical access - DLT or blocker acceptable). Failure to make this distinction loses marks immediately.

2. INDICATIONS FOR ONE-LUNG VENTILATION

Classification: Absolute vs. Relative (Barash, 9e; Morgan & Mikhail, 7e)

3. PHYSIOLOGY OF ONE-LUNG VENTILATION

A. Six Physiological States in the Lateral Decubitus Position

B. The Two Key Complications of OLV Physiology

C. Shunt During OLV

TWO-LUNG VENTILATION vs. ONE-LUNG VENTILATION: SHUNT COMPARISON

Two-lung ventilation:
  Qs/Qt ≈ 10% (5% each lung)
  PaO2: Normal
  
One-lung ventilation (without HPV compensation):
  Nondependent lung collapsed but still perfused = OBLIGATORY SHUNT
  Right-to-left shunt ≈ 20-30%
  A-a gradient widens → PaO2 falls

With HPV compensation:
  Blood flow to nondependent lung ↓ by ~50%
  Net shunt reduced to ≈ 17-22%
  PaO2 stabilises (usually after 20-30 min; nadir at onset)
  
Two contributors to hypoxemia during OLV:
  1. Shunt through nonventilated lung (obligatory)
  2. Atelectasis in dependent (ventilated) lung → local shunt + low V/Q

"During one-lung anesthesia, there are two main contributors to impaired oxygenation: (1) the persisting blood flow through nonventilated lung and (2) development of atelectasis in the dependent lung." - Miller's Anesthesia 10e

D. Hypoxic Pulmonary Vasoconstriction (HPV) - The Body's Defence

1. High mean airway pressures in ventilated lung (high PEEP, hyperventilation, high PIP) - produce HPV in the ventilated lung
2. Low FiO2 - causes HPV in the ventilated lung
3. Vasoconstrictors - greater effect on normoxic than hypoxic vessels
4. Intrinsic PEEP (auto-PEEP) from inadequate expiratory times

Examiner Pearl: Examiners love asking: "Which drugs inhibit HPV?" The key answer is volatile anaesthetics - but only at >1 MAC do they significantly impair HPV. At <1 MAC, their effect is minimal. Propofol (TIVA) has no effect on HPV and may therefore be preferred in patients at high risk of hypoxaemia.

4. DEVICES FOR LUNG SEPARATION AND ISOLATION

Overview of Four Techniques

A. Double-Lumen Tubes (DLTs)

• Longer endobronchial lumen entering a main bronchus
• Shorter endotracheal lumen terminating in lower trachea
• Preformed curve allowing preferential bronchial entry
• Endobronchial cuff (distal, smaller)
• Endotracheal cuff (proximal, larger)

1. Distorted anatomy of the left main bronchus (intraluminal or extraluminal mass)
2. Compression of the left main bronchus by descending thoracic aortic aneurysm
3. Left-sided pneumonectomy
4. Left-sided single lung transplantation
5. Left-sided sleeve resection

"Either a left-sided or right-sided double-lumen tube can be used in most surgical procedures; for simplicity, many practitioners prefer to use left-sided tubes for nearly every case." - Morgan & Mikhail 7e

• Laryngoscopy with curved (MacIntosh) blade preferred - more room for the large DLT
• Video laryngoscopy increasingly used (Morgan & Mikhail 7e)
• Initial blind placement then confirm with fiberoptic bronchoscopy (FOB) - mandatory in modern practice

• Airway trauma: tracheal/bronchial laceration or rupture (from oversized DLT or distal migration)
• Signs: unexpected air leak, subcutaneous emphysema, massive airway bleeding, protrusion of cuffs into surgical field
• Tension pneumothorax in the dependent, ventilated lung during OLV

B. Bronchial Blockers (BBs)

• Preferred in difficult airway patients (awake nasotracheal/orotracheal intubation first, then BB placed)
• Patients with tracheostomy
• Patients with previous contralateral pulmonary resection (selective lobar blockade)
• When postoperative mechanical ventilation is anticipated (SLT already in place)
• Paediatric patients (Cohen Blocker and Fuji Uniblocker can be placed exterior to SLT)

• More likely to dislodge intraoperatively than DLT
• Low-pressure high-volume cuffs; peak airway pressure should be kept below 30 cmH2O
• Cannot provide robust suctioning (critical limitation)
• Once balloon deflated, diseased material can contaminate the healthy lung
• Not suitable for lung isolation (protection from blood/pus) - DLT mandatory in that setting

"When lung protection is necessary, DLTs are preferable to endobronchial blockers (BBs) because the low-pressure high-volume cuff of the BB would not provide an adequate protective seal to prevent contamination of the dependent lung." - Barash 9e

• Direct fiberoptic visualisation of inflated cuff
• Or: lumen connected to suction to detect discrepancy between inspiratory and expiratory volumes (Barash 9e)

5. CONFIRMATION OF CORRECT POSITION

1. Clinical assessment
2. Chest movement visualization
3. Auscultation
4. Pressure/volume flow profile
5. Fiberoptic bronchoscopy (FOB) - mandatory in modern practice

• Blue bronchial cuff just visible at the entrance of left main bronchus
• Carina visible above the white line marker
• No obstruction of left upper lobe bronchus

"It is a common practice to visualize the tip of the blue bronchial cuff at the level of the carina to ensure that the left upper lobe orifice is not obstructed. Once the patient is turned into the lateral position, the position of the DLT should be rechecked to exclude dislocation of the tube during positioning." - Barash 9e

6. MANAGEMENT OF ONE-LUNG VENTILATION

A. Pre-OLV Preparation: Speed of Lung Collapse

B. Ventilator Settings During OLV - Lung-Protective Ventilation

RECOMMENDED OLV VENTILATOR SETTINGS (Lung-Protective Strategy)
═══════════════════════════════════════════════════════════════
FiO2:          1.0 (FiO2 of 1 generally recommended; some use 0.5-0.8)
VT:            5-6 mL/kg predicted body weight (max)
               [range 4-8 mL/kg debated - see below]
Plateau Paw:   < 25 cmH2O
Peak Paw:      < 35 cmH2O
PEEP:          Titrated to optimal compliance (usually 5-10 cmH2O)
Mode:          Pressure-controlled ventilation (PCV) preferred
               [limits peak and plateau pressure; better flow pattern]
RR:            Adjusted to maintain normocapnia or permissive hypercapnia
═══════════════════════════════════════════════════════════════

"There is no evidence to confirm that the data derived from ARDS patients can be applied to the thoracic surgical population." - Barash 9e (important nuance)

• PEEP to the dependent (ventilated) lung prevents atelectasis and improves V/Q matching
• BUT excessive PEEP in the dependent lung increases mean airway pressure, shifts blood flow to the nondependent collapsed lung, and worsens PaO2
• PEEP should be titrated to optimal compliance, not applied universally
• Caution: Avoid high PEEP in emphysematous patients (risk of auto-PEEP and air trapping)

• PCV limits peak and plateau airway pressures (barotrauma protection)
• PCV provides a decelerating flow pattern - more even gas distribution
• Morgan & Mikhail state: "Although there is no unequivocal evidence that one mode may be more beneficial, pressure-controlled ventilation may diminish the risk of barotrauma"
• Practical advantage of PCV: Surgeon may inadvertently compress the bronchus; PCV's pressure-limited nature is protective

C. FiO2 During OLV

• FiO2 of 1.0 is generally recommended during OLV (Barash 9e) - provides margin of safety
• A high FiO2 may cause absorption atelectasis and paradoxically increase shunt
• Some clinicians use FiO2 0.5-0.8 to reduce absorption atelectasis risk
• Barash: "Some clinicians use an O2 80%/N2O 20% mixture as long as SpO2 is maintained in a safe range"
• If FiO2 is reduced in the dependent lung, HPV will be triggered there too - worsening overall oxygenation

D. Choice of Anaesthetic Agent

• All current techniques have been used successfully (Morgan & Mikhail 7e)
• Volatile agents (isoflurane, sevoflurane, desflurane): potent bronchodilation; depress airway reflexes; inhibit HPV dose-dependently but minimally at <1 MAC
• Sevoflurane may be the most potent bronchodilator of volatile anaesthetics (Miller's Anesthesia 10e)
• Propofol (TIVA): no effect on HPV - theoretical advantage; combined with opioids
• If epidural opioids planned for postoperative analgesia, minimise IV opioids intraoperatively (Morgan & Mikhail 7e)
• Ketamine and propofol reduce bronchospasm on induction (vs. barbiturates, etomidate - no benefit) (Miller's Anesthesia 10e)
• Neuromuscular blockade: nondepolarizing NMB facilitates rib spreading and anaesthetic management

• Excessive fluid administration is associated with ALI postoperatively
• In lateral decubitus position, promotes "lower lung syndrome" - fluid transudation into dependent lung increasing shunting (Morgan & Mikhail 7e)
• Goal-directed fluid therapy is now advocated during thoracic surgery

7. PREDICTION AND TREATMENT OF HYPOXAEMIA DURING OLV

A. Predictors of Desaturation (Box 49.7, Miller's Anesthesia 10e)

"The most important predictor of PaO2 during OLV is the PaO2 during two-lung ventilation, specifically the intraoperative PaO2 during TLV in the lateral position before OLV." - Miller's Anesthesia 10e

"The mean PaO2 difference between left and right thoracotomies during stable OLV is approximately 100 mm Hg." - Miller's Anesthesia 10e

B. Timing of Hypoxaemia

• PaO2 falls to its nadir at 20-30 minutes after initiation of OLV
• Then stabilises or may rise slightly as HPV increases over the next 2 hours
• "The majority of patients who desaturate do so quickly and within the first 10 minutes of OLV" (Miller's Anesthesia 10e)

C. Treatment Algorithm for Hypoxaemia During OLV

HYPOXAEMIA DURING OLV - STEPWISE TREATMENT PROTOCOL
══════════════════════════════════════════════════════

STEP 1: SEVERE/PRECIPITOUS DESATURATION
  → Resume two-lung ventilation (reinflate nondependent lung)
  → Diagnose cause, institute prophylaxis, re-attempt OLV
  
STEP 2: GRADUAL DESATURATION - CHECK BASICS FIRST
  ├── Confirm FiO2 = 1.0
  ├── Check DLT/blocker position via FOB (lobar obstruction?)
  └── Check haemodynamics (cardiac output adequate?)
      [IVC compression by surgeon → ↓CO → rapid desaturation]
  
STEP 3: VENTILATED LUNG INTERVENTIONS
  ├── Recruitment maneuver: inflate to 20 cmH2O for 15-20 sec
  │   [Note: transient further drop in PaO2 during maneuver]
  ├── Increase PEEP to ventilated lung
  │   [Avoid in emphysema/COPD]
  └── Reduce volatile anesthetic to ≤1 MAC (if >1 MAC)
  
STEP 4: NONDEPENDENT LUNG INTERVENTIONS (ascending order)
  ├── Apneic oxygen insufflation to nondependent lung
  ├── CPAP 1-2 cmH2O to nondependent lung
  │   [Apply recruitment maneuver BEFORE CPAP]
  │   [Single most effective maneuver - Barash 9e]
  │   [Limitation: CPAP interferes with VATS visualization]
  └── Partial ventilation techniques:
      - Intermittent PPV
      - Fiberoptic lobar insufflation
      - Selective lobar collapse (blocker)
      - Small tidal volume ventilation
  
STEP 5: PHARMACOLOGIC / MECHANICAL
  ├── Almitrine (pulmonary vasoconstrictor - potentiates HPV)
  ├── Inhaled NO + almitrine combination (better than NO alone)
  ├── Stop vasodilators (NTG, SNP)
  ├── Mechanical compression of nondependent lung
  │   [Surgeon clamps pulmonary artery if all else fails]
  └── Venovenous ECMO (last resort)

══════════════════════════════════════════════════════

Examiner Pearl on CPAP vs. PEEP:

• CPAP to the nondependent (collapsed, non-ventilated) lung = single most effective maneuver (Barash 9e). Maintains alveolar patency, allows some O2 uptake. Dose: 5-10 cmH2O.
• PEEP to the dependent (ventilated) lung = prevents atelectasis but risk of diverting blood to collapsed lung if excessive.
• These work synergistically but must be carefully titrated.

8. OLV-INDUCED LUNG INJURY (ALI/VILI)

• Overall: 2.5% of all lung resections
• After pneumonectomy: 7.9%
• When ALI occurs: mortality/major morbidity ~40% (Morgan & Mikhail 7e)

• Extent of lung injury depends on total mechanical energy delivered per unit time
• High MP is independently associated with increased in-hospital mortality, ICU mortality, 30-day mortality, ventilator-free days (Serpa Neto et al., 8207 patients)
• In lateral decubitus position, weight of contralateral hemithorax adds chest wall restriction - MP delivered to dependent lung INCREASES during OLV
• Reducing VT from 8 to 5 mL/kg did NOT reduce MP (Chiuemello et al.) - simply reducing VT may be insufficient

• Deliberate hypercapnia (PaCO2 60-70 mmHg) during OLV:
  • Inhibits local inflammatory response
  • Decreases airway pressure
  • Increases lung compliance
  • Improves PaO2/FiO2 following surgery
  • No severe adverse effects reported (Barash 9e - Gao et al., 50 patients)
• Permissive hypercapnia is reasonable in patients with elevated CO2 tensions who have adequate SpO2 (Morgan & Mikhail 7e)

9. SPECIAL SITUATIONS

A. Lung Isolation vs. Lung Separation - The Critical Distinction

B. OLV in the Difficult Airway Patient

• Perform awake nasotracheal or orotracheal intubation with an SLT first
• Then place an independent bronchial blocker to achieve lung separation
• Cohen Blocker and Fuji Uniblocker can be placed exterior to the SLT (through glottis or tracheostomy) - allows use of a smaller SLT (Miller's Anesthesia 10e)

C. OLV in Patients with Tracheostomy

• Standard DLTs cannot be used
• Options: Specific tracheostomy DLTs, or SLT via tracheostomy + bronchial blocker

D. Tubeless Thoracic Surgery (Barash 9e)

• Cooperative patient
• BMI <40
• No difficult airway (for emergency intubation)
• Skilled surgeon comfortable with tubeless approach
• Procedures: carefully selected VATS only

• Avoids PPV-related lung injury
• Avoids muscle relaxants → less atelectasis in dependent zone
• No residual neuromuscular blockade
• Avoids laryngeal/tracheal injury
• Lower postoperative complication rate, shorter hospital stay, lower perioperative mortality (meta-analysis, Zhang et al.) (Barash 9e)

10. GAP CHECK - CONFLICTING RECOMMENDATIONS AND UNIQUE POINTS

11. SUMMARY FLOWCHART: OLV MANAGEMENT AT A GLANCE

PATIENT REQUIRING THORACIC SURGERY WITH OLV
══════════════════════════════════════════════════════════

PREOPERATIVE ASSESSMENT
  ├── PFTs: FVC, FEV1, DLCO; ppoFEV1 calculation
  ├── Predict OLV tolerance: PaO2 TLV, V/Q scan, side
  ├── Assess airway: standard vs. difficult
  └── Determine need: Lung ISOLATION or Lung SEPARATION?

DEVICE SELECTION
  ├── Isolation needed → DLT (mandatory)
  ├── Separation only + normal airway → DLT (preferred)
  ├── Difficult airway → Awake intubation SLT + BB
  └── Tracheostomy → SLT + BB

DLT SELECTION
  ├── Left-sided DLT: default for most cases
  └── Right-sided DLT: left pneumonectomy, left sleeve resection,
      left bronchial compression/distortion, left lung transplant

CONFIRM POSITION
  ├── Clinical exam + auscultation
  ├── FOB via tracheal lumen (mandatory)
  └── RECHECK after lateral positioning

OLV VENTILATION SETTINGS
  FiO2 1.0 | VT 5-6 mL/kg PBW | Plateau <25 cmH2O
  PEEP titrated to compliance | PCV preferred | permissive hypercapnia

MONITOR OXYGENATION
  ├── Nadir at 20-30 min (most desaturate in first 10 min)
  ├── SpO2 target ≥ 95%
  └── PaO2 target: guide by clinical context

HYPOXAEMIA? → Follow stepwise treatment (see Section 7)

REEXPANSION
  └── Before chest closure: expand all segments manually
      under direct vision; test bronchial stump under water
      at 30 cmH2O sustained pressure

══════════════════════════════════════════════════════════

12. CONCLUSION

Sources Cited

• Barash, Cullen & Stoelting's Clinical Anesthesia, 9e - Ch. 38 (Physiology of OLV, Lung Isolation/Separation, Management of OLV, DLTs, BBs, Tidal Volume, CPAP, PEEP, Tubeless)
• Miller's Anesthesia, 10e - Ch. 49 (Management of OLV, Prediction of Desaturation, Treatment of Hypoxaemia, Bronchial Blockers, Lung Collapse Speed) and Ch. 12 (OLV overview)
• Morgan & Mikhail's Clinical Anesthesiology, 7e - Ch. 25 (Indications Table 25-1, DLTs, Anatomic Considerations, HPV inhibitors, Management of OLV, ALI incidence, Protective Ventilation, Maintenance of Anaesthesia)

Celiac Plexus Block (CPB) and Celiac Plexus Neurolysis (CPN)

MD Anaesthesia | Distinction-Level Theory Answer

1. INTRODUCTION AND DEFINITIONS

Examiner Pearl: CPN causes permanent destruction and is therefore contraindicated in any patient who remains a surgical candidate. CPB with local anaesthetic and steroid is the temporary, reversible option. Conflating these two is a common examination error.

2. ANATOMY OF THE CELIAC PLEXUS

A. Anatomical Location

• A dense network of ganglia and interconnecting fibers (not a single discrete structure)
• Located caudal to the diaphragm (in an antecrural position)
• Surrounds the origin of the celiac trunk and the abdominal aorta
• Anterior to the crura of the diaphragm, surrounding the celiac and superior mesenteric arteries (Barash, 9e)

B. The Celiac Ganglia

• Number: 1-5 ganglia (variable) (multiple sources agree)
• Size: 0.5-4.5 cm (Clinical GI Endoscopy 3e)
• Location: At the level of T12-L2 (Clinical GI Endoscopy 3e); body of L1 (Morgan & Mikhail 7e)
• Right side: Posterior to the inferior vena cava (Morgan & Mikhail 7e)
• Left side: Just lateral to the aorta (Morgan & Mikhail 7e)
• Both sides: Posterior to the pancreas (Morgan & Mikhail 7e)

C. Neural Connections

D. Visceral Territory of the Celiac Plexus

• Left side of the colon
• Rectum
• Pelvic organs

E. The Splanchnic Nerves - Clinically Important Distinction

• Retrocrural approach to celiac plexus = the injectate spreads over the splanchnic nerves (above the diaphragm, posterior to the crura)
• Antecrural approach = "true" CPN - injection anterior to the diaphragm, spread over the celiac ganglia themselves

3. INDICATIONS

• Pelvic pain (inferior hypogastric plexus block required)
• Left colonic or rectal pain
• Somatic/neuropathic pain (CPN targets visceral afferents only)
• Chronic pancreatitis as a primary indication (current guidelines do NOT recommend) (Sleisenger & Fordtran's)

Guideline Endorsements (Barash 9e):

• European Association for Palliative Care (EAPC) - strongly endorses CPB for pancreatic cancer pain
• American Society of Pain and Neuroscience (ASPN) - strongly endorses CPB for pancreatic cancer pain

4. APPROACHES AND TECHNIQUES

Classification of Approaches

APPROACHES TO CELIAC PLEXUS BLOCK/NEUROLYSIS
═══════════════════════════════════════════════════════

A. PERCUTANEOUS POSTERIOR APPROACHES (Fluoroscopy/CT guided)
   ├── 1. Retrocrural (Posterior Paravertebral)
   ├── 2. Anterocrural (Anterior Peri-aortic / "True CPN")
   ├── 3. Posterior Transaortic
   └── 4. Transdiscal
   
B. ANTERIOR APPROACH
   └── Anterior Peri-aortic (ultrasound or CT guided)
   
C. ENDOSCOPIC ULTRASOUND (EUS) GUIDED
   ├── Central (single, midline, above celiac trunk)
   ├── Bilateral (left + midline/right of celiac trunk)
   └── Direct Celiac Ganglia Injection (EUS-CGN)
   
D. SURGICAL / INTRAOPERATIVE
   └── At time of laparotomy / laparoscopy

E. EMERGING TECHNIQUES
   └── EUS-guided Radiofrequency Ablation (EUS-RFA)

═══════════════════════════════════════════════════════

A. Percutaneous Posterior Approaches (Fluoroscopy / CT-Guided)

• Needle(s) inserted 7-8 cm from the midline at the inferior edge of the spinous process of L1
• Advanced under fluoroscopic guidance toward the midline
• Passes under the edge of the 12th rib
• Lateral view: Needle tip anterior to the body of L1
• AP view: Needle tip close to midline overlying the same vertebral body
• CT-guided: Tip lies anterolateral to the aorta at a level between the celiac and superior mesenteric arteries
• Volume: 15-20 mL local anaesthetic per side

• Needle tip in the upper third of L1, approximately 1 cm beyond the border of the vertebral body
• Contrast spreads cephalad (over the splanchnic nerves)
• Volume: 15-30 mL per retrocrural space

• Needle tip in the lower third of L1, approximately 3 cm beyond the border of the vertebral body
• Contrast spreads caudad and in front of the aorta (over celiac ganglia)
• Volume: 30-50 mL for the antecrural space

• Local anaesthetic first to predict efficacy before committing to neurolysis (Barash 9e)
• If pain relief is confirmed, proceed to neurolytic injection
• If initial block reduces pain, may be repeated to confirm and exclude placebo effect (Morgan & Mikhail 7e)

B. EUS-Guided Approach

• Hydration with 500-1000 mL normal saline to minimise hypotension risk (Clinical GI Endoscopy 3e)
• Yamada's also specifies: 500 mL saline pre-procedure (Yamada's 7e)
• Moderate sedation or general anaesthesia
• Continuous monitoring during and for 2 hours after procedure
• Blood pressure checked supine and erect before discharge to assess for orthostasis

• Uncorrectable coagulopathy (INR >1.5)
• Thrombocytopenia (platelets <50,000/L)
• Inadequate hydration
• Altered anatomy prohibiting visualisation/access to celiac plexus or ganglia

Examiner Pearl - EUS vs. CT guidance: Multiple sources indicate EUS is safer, more effective, and more long-lasting than CT-guided approaches (Sleisenger & Fordtran's). The EUS approach is advantageous because of: (1) accurate needle positioning above/lateral to the celiac trunk; (2) Doppler control to avoid vessel interposition; (3) real-time visualisation; (4) can be done immediately after diagnostic EUS (Yamada's 7e).

5. DRUG DOSES AND AGENTS

A. For Celiac Plexus Block (CPB) - Temporary/Reversible

B. For Celiac Plexus Neurolysis (CPN) - Permanent

• 98% dehydrated alcohol + 0.75% Marcaine (bupivacaine) in a 70:30 ratio (alcohol:bupivacaine)
• Total volume: 10-20 mL

C. For Splanchnic Nerve Block

6. OUTCOMES AND EFFICACY

Pancreatic Cancer Pain (CPN - Primary Indication)

• Splanchnic neurolysis has been reported to have superior results compared to celiac plexus neurolysis for cancer of the pancreatic body and tail (Barash 9e)

Chronic Pancreatitis Pain (CPB)

Examiner Pearl - Chronic Pancreatitis: CPB may be used as adjunct therapy to reduce opioid requirement or facilitate step-down from IV to oral analgesics, but is not a first-line or guideline-recommended treatment for chronic pancreatitis. CPN is contraindicated if surgical candidacy remains.

EUS-Guided Radiofrequency Ablation (EUS-RFA) - Emerging

• A randomised trial comparing EUS-RFA to EUS-CPN for palliative pain in pancreatic cancer showed: EUS-RFA had significantly less pain, fewer GI symptoms, and improved quality of life (Yamada's 7e)

7. COMPLICATIONS

Splanchnic Nerve Block Complications

• Hypotension
• Pneumothorax (needle must maintain contact with vertebral body at all times to avoid this)
• Injury to azygos vein (right side)
• Injury to hemiazygos vein and thoracic duct (left side)

Celiac Plexus Block/Neurolysis Complications

Percutaneous Approaches

Examiner Pearl - Paraplegia: This is the most feared catastrophic complication. The mechanism is spasm of lumbar segmental arteries that perfuse the anterior spinal cord (including the artery of Adamkiewicz/radicularis magna), direct vascular injury, or retrograde spread of neurolytic agent to the nerve roots or spinal cord. The artery of Adamkiewicz most commonly arises from the left intercostal or lumbar arteries at T9-T12 - in close proximity to the injection zone.

Prevention of Hypotension:

• Adequate IV hydration before the procedure (Morgan & Mikhail 7e; Clinical GI Endoscopy 3e)
• Clinical GI Endoscopy 3e: 500-1000 mL IV normal saline preprocedure

EUS-Guided Complications (Clinical GI Endoscopy 3e)

8. PERIOPERATIVE MANAGEMENT PROTOCOL

CELIAC PLEXUS BLOCK/NEUROLYSIS - MANAGEMENT FLOWCHART
═══════════════════════════════════════════════════════════

STEP 1: PATIENT SELECTION
  ├── Diagnosis confirmed (pancreatic cancer / chronic pancreatitis)
  ├── Pain predominantly visceral, upper abdominal
  ├── Pharmacologic analgesics inadequate or causing side effects
  ├── CPN: Confirm patient NOT a surgical candidate
  └── Exclude: coagulopathy (INR>1.5), thrombocytopenia (<50k),
              altered anatomy, inadequate hydration

STEP 2: CHOOSE APPROACH
  ├── EUS available + skilled operator → EUS-guided (preferred)
  ├── EUS not available → Percutaneous posterior with CT guidance
  ├── No CT → Fluoroscopic guidance
  └── At laparotomy/laparoscopy → Intraoperative

STEP 3: CHOOSE AGENT
  ├── Malignant pain → CPN: Absolute ethanol 98%
  │   ± diagnostic local anaesthetic block first
  └── Chronic pancreatitis → CPB: Bupivacaine + triamcinolone

STEP 4: PREPROCEDURE PREPARATION
  ├── IV hydration: 500-1000 mL normal saline
  ├── Consent including risk of paraplegia, hypotension, diarrhoea
  ├── Continuous monitoring setup (SpO2, ECG, BP, NIBP)
  └── Sedation/anaesthesia plan (conscious sedation or GA)

STEP 5: PROCEDURE
  ├── Confirm position: aspiration test before each injection
  ├── Diagnostic LA injection if CPN planned (optional)
  └── Neurolytic injection after efficacy confirmed

STEP 6: POST-PROCEDURE MONITORING
  ├── Continuous monitoring for ≥2 hours
  ├── BP checked supine AND erect before discharge (orthostasis)
  ├── Neurological assessment
  └── Discharge with instructions: orthostatic precautions

STEP 7: FOLLOW-UP
  ├── Reassess pain scores at 4, 8, 12 weeks
  ├── Splanchnic nerve block → consider RFA at T11/T12 if effective
  └── If first block effective: repeat to exclude placebo effect
      before proceeding to neurolysis

═══════════════════════════════════════════════════════════

9. SPLANCHNIC NERVE BLOCK - RELATED AND IMPORTANT

• Less likely to block the lumbar sympathetic chain
• Requires less anaesthetic

• Needle: 6-7 cm from midline at lower end of T11 spinous process
• Advanced under fluoroscopy to anterolateral surface of T12
• Volume: 10 mL local anaesthetic per side
• Needle must maintain contact with vertebral body at all times (prevents pneumothorax)

• Repeat to exclude placebo effect
• If confirmed beneficial: radiofrequency ablation of splanchnic nerves at T11-T12 for potentially longer duration
• Performing on one side at a time is advised due to pneumothorax risk

10. GAP CHECK - CONFLICTING DATA AND UNIQUE POINTS

11. SUMMARY TABLE: CPB vs. CPN vs. SPLANCHNIC BLOCK

12. CONCLUSION

Sources Cited

• Barash, Cullen & Stoelting's Clinical Anesthesia, 9e - Ch. 56 (Celiac Plexus Block, approaches, volumes, complications, EAPC/ASPN guidelines, splanchnic neurolysis vs CPN for body/tail cancer)
• Morgan & Mikhail's Clinical Anesthesiology, 7e - Ch. 47 (Splanchnic Nerve Block, Celiac Plexus Block anatomy, technique, doses, complications including artery of Adamkiewicz, intravascular injection nuances)
• Clinical Gastrointestinal Endoscopy, 3e - Chs. 51 & 59 (EUS-guided CPB/CPN techniques, patient preparation, contraindications, drug protocol, EUS-CGN, bilateral vs. unilateral data, complication incidences, Cochrane and Eisenberg meta-analyses)
• Yamada's Textbook of Gastroenterology, 7e - Ch. 132 (EUS-CPN technique, bilateral vs. central RCT, EUS-CGN survival concern, EUS-RFA vs. EUS-CPN, CPB not recommended in CP)
• Sleisenger & Fordtran's Gastrointestinal and Liver Disease - Ch. 15 (Nerve blocks and neurolysis; guidelines do not recommend CPB/CPN for chronic pancreatitis; EUS safer, more effective, more long-lasting than CT guidance)

Celiac Plexus Block & Neurolysis — Concise High-Yield Answer

MD Anaesthesia | 4–5 Page Summary

1. DEFINITIONS — THE CRITICAL DISTINCTION

Examiner Pearl: Conflating CPB and CPN is the most common error. CPN permanently destroys the plexus — never perform in a potentially resectable patient.

2. ANATOMY

• Retrocrural injection → injectate spreads over splanchnic nerves (above diaphragm)
• Anterocrural injection → "true" CPN → spreads over celiac ganglia (below diaphragm, anterior to aorta)

3. INDICATIONS

Current guidelines (Sleisenger & Fordtran's): CPB and CPN are NOT recommended as primary therapy for chronic pancreatitis.

4. APPROACHES — CLASSIFICATION

APPROACHES TO CELIAC PLEXUS BLOCK/NEUROLYSIS
═══════════════════════════════════════════════
A. Percutaneous Posterior (Fluoroscopy / CT)
   1. Retrocrural
   2. Anterocrural ("true" CPN)
   3. Transaortic
   4. Transdiscal

B. Anterior (Ultrasound / CT)

C. EUS-Guided (PREFERRED)
   1. Central single injection
   2. Bilateral injection
   3. Direct celiac ganglia injection (EUS-CGN)

D. Surgical/Intraoperative

E. Emerging: EUS-guided Radiofrequency Ablation (EUS-RFA)
═══════════════════════════════════════════════

Percutaneous Posterior Technique (Fluoroscopy/CT)

• Position: Prone
• Needle: 15 cm, 22-gauge
• Inserted 7–8 cm from midline at inferior edge of L1 spinous process
• Lateral view: tip anterior to body of L1; AP view: close to midline
• CT-guided: tip anterolateral to aorta between celiac and superior mesenteric arteries

EUS-Guided Approach (Preferred)

• IV hydration: 500–1000 mL normal saline (prevent hypotension)
• Patient: left lateral decubitus
• Sedation: moderate sedation or GA
• Monitoring: continuous, including 2 hours post-procedure; BP checked supine AND erect before discharge

• INR >1.5 / Thrombocytopenia (<50,000/L)
• Inadequate hydration
• Altered anatomy preventing access

5. DRUGS AND DOSES

Diagnostic block before neurolysis: Always consider a test injection of local anaesthetic first to predict efficacy and confirm non-placebo response before committing to permanent neurolysis. (Barash 9e)

Splanchnic advantage (Morgan & Mikhail 7e): Splanchnic block uses less anaesthetic and is less likely to block the lumbar sympathetic chain than CPN. Splanchnic neurolysis also has superior results to CPN specifically for pancreatic body and tail cancer. (Barash 9e)

6. EFFICACY

Important: CPN is an adjunct to standard analgesic therapy, not a replacement. Most patients still require ongoing analgesics after CPN. (Yamada's 7e)

7. COMPLICATIONS

Common Side Effects

Serious Complications

Examiner Pearl — Paraplegia: The artery of Adamkiewicz (arteria radicularis magna) most commonly arises from T9–T12, in close proximity to the injection zone. Spasm or direct injury compromises anterior spinal cord perfusion → anterior spinal artery syndrome (motor paralysis, loss of pain/temperature; proprioception preserved).

8. PERIOPERATIVE PROTOCOL SUMMARY

PRE-PROCEDURE
  ✓ Confirm indication + surgical candidacy (CPN: no surgical candidate)
  ✓ Check INR (<1.5), platelets (>50,000)
  ✓ IV hydration: 500–1000 mL normal saline
  ✓ Consent: paraplegia, hypotension, diarrhoea, failure

PROCEDURE
  ✓ EUS preferred; CT/fluoroscopy if EUS unavailable
  ✓ Aspiration test before every injection
  ✓ Diagnostic LA block first if neurolysis planned
  ✓ Continuous monitoring

POST-PROCEDURE (≥2 hours monitoring)
  ✓ BP supine AND erect before discharge
  ✓ Neurological assessment
  ✓ Discharge instructions: orthostatic precautions
  ✓ Follow up: reassess pain at 4, 8, 12 weeks

9. GAP CHECK — HIGH-YIELD CONFLICTING/UNIQUE POINTS

10. CONCLUSION

One-line exam summary: CPB = reversible (LA + steroid), CPN = permanent (ethanol/phenol); EUS-guided preferred; 70–90% pain relief in pancreatic cancer; commonest complication = hypotension; most feared = paraplegia.