Complications of Rapid Sequence Induction and Moderate Sedation, and the Difficult Airway Ryan J Fink, MD Raquel Bartz, MD Duke University Medical Center Dept. of Anesthesiology

Objectives Goals of airway management Recognizing the difficult airway Complications surrounding airway management Other Complications – Rapid Sequence Induction/Intubation – Moderate Sedation

RSI and MS and the Airway RSI = planned intubation MS = intubation as recue technique Airway evaluation for all patients Plan on intubating

Emergency Airway Management: Indications for Intubation Loss of Airway Protection Loss of gag/cough (GCS ≤ 8) Airway obstruction (i.e. edema) Anticipated loss of airway control (i.e. worsening stridor, burns)

Emergency Airway Management: Indications for Intubation Failure of Ventilation (PaCO2 > 50 mmHg) – Neurological problems Sedation, narcosis, brain or spinal cord injury, peripheral nerve disease (i.e. Guillian-Barre) – Muscular problems Myasthenia gravis, steroid-induced myopathy – Anatomical problems Rib fractures, pneumothorax, abdominal hypertension – Gas exchange Problems Acute lung injury, lung contusion

Emergency Airway Management: Indications for Intubation Failure of Oxygenation (PaO2 <60mmHg) – Diffusion abnormality Pulmonary edema, alveolar proteinosis, aspiration – Increased Dead Space (ventilations w/o perfusion) Pulmonary embolus, shallow breathing – Shunt (perfusion w/o ventilation) Airway collapse, pneumonia, acute lung injury

Loss of Airway Protection + Failure of Ventilation + Failure of Oxygenation = Respiratory Failure and Need for Intubation Emergency Airway Management: Indications for Intubation

Airway Assessment Goals: – Assess for risk of difficult mask ventilation – Assess for risk of difficult intubation

Predictors of Difficult Mask Ventilation M = difficult Mask seal (full beard) O = Obese or airway Obstruction A = advanced Age N = No teeth S = Stiff lungs/history of Snoring

Predictors of Difficult Intubation: Mallampati Classification

↑ MP score correlates with difficult intubation – Relative Risk of difficult intubation Class III 7.5 times compared to class I – Sensitivity = 60-80% – Specificity = 53-80% – Positive Predictive Value = 20% Longnecker, Anesthesiology, 2008 Fleischer, Evidence Based Practice of Anesthesiology, 2009

Weight (>90kg) Head/neck movement (≤ 90⁰) Poor jaw mobility Incisior gap (≤ 5 cm) Difficulty with lower jaw subluxation Receding mandible Protruding maxillary teeth Short thyromental distance (<6cm) Other anatomic changes (tumor, goiter, etc…) Predictors of Difficult Intubation

Small mandible

Large tongue, airway edema

Limited mouth opening

Protruding front teeth

Airway Assessment: Helping to Prevent Complications Identify patients who might be difficult to ventilate and intubate prior to proceeding Call for assistance and have back-up plans Know potential complications Prevent potential complications – PREPARATION

RSI Complications Mort Study; N = 102Jaber Study; N = 251Schwartz Study; N = 238 Hypoxemia : 17%Hypoxemia: 26% Aspiration: 1.7%Aspiration: 4% Regurgitation: 4.4%Dental Injury: 1% Surgical Airway: 0.4%Pneumothorax: 1% Esophageal Intubation: 10% Esophageal Intubation: 4% Esophageal Intubation: 8% Bradycardia: 3.5%Severe Hemodynamic Collapse: 25% Cardiac Arrest: 2%Cardiac Arrest: 1%Cardiac Arrest/ Death 3% > 3 Attempts: 10%> 3 Attempts: 11% Mort TC J Clin Anesth 2004; 16: Schwartz DE Anesthesiology 1995; 82: Jaber S Crit Care Med 2006; 34:

RSI Complications ↑ complications with ↑ number of attempts – Dental injury – > 3 attempts = severe hypoxemia in all patients – > 3 attempts = 25% require surgical airway Prevention/Management – Thorough airway assessment – If unsuccessful, make adjustments Position, equipment, or personnel Mort TC J Clin Anesth 2004; 16:508

RSI Complications Mort Study; N = 102Jaber Study; N = 251Schwartz Study; N = 238 Hypoxemia : 17%Hypoxemia: 26% Aspiration: 1.7%Aspiration: 4% Regurgitation: 4.4%Dental Injury: 1% Surgical Airway: 0.4%Pneumothorax: 1% Esophageal Intubation: 10% Esophageal Intubation: 4% Esophageal Intubation: 8% Bradycardia: 3.5%Severe Hemodynamic Collapse: 25% Cardiac Arrest: 2%Cardiac Arrest: 1%Cardiac Arrest/ Death 3% > 3 Attempts: 10%> 3 Attempts: 11% Mort TC J Clin Anesth 2004; 16: Schwartz DE Anesthesiology 1995; 82: Jaber S Crit Care Med 2006; 34:

RSI Complications Esophageal Intubation – Delay to ventilation  hypoxemia – Gastric insufflation  aspiration – Esophageal tear – Cardiac arrest/death Prevention/Management – Airway assessment and preparation – Avoid “blind” intubations – Ascultate, bag compliance, + end tidal CO2 – Avoid gastric insufflation, remove the ETT

RSI Complications Mort Study; N = 102Jaber Study; N = 251Schwartz Study; N = 238 Hypoxemia : 17%Hypoxemia: 26% Aspiration: 1.7%Aspiration: 4% Regurgitation: 4.4%Dental Injury: 1% Surgical Airway: 0.4%Pneumothorax: 1% Esophageal Intubation: 10% Esophageal Intubation: 4% Esophageal Intubation: 8% Bradycardia: 3.5%Severe Hemodynamic Collapse: 25% Cardiac Arrest: 2%Cardiac Arrest: 1%Cardiac Arrest/ Death 3% > 3 Attempts: 10%> 3 Attempts: 11% Mort TC J Clin Anesth 2004; 16: Schwartz DE Anesthesiology 1995; 82: Jaber S Crit Care Med 2006; 34:

Aspiration – Difficult to visualize vocal cords and intubate – Pneumonia – Airway obstruction  Hypoxemia  Death Prevention/Management – Airway assessment and preparation – ? Pharmacotherapy – Intubate  suction trachea before ventilation – 30 degrees head-down tilt – Treat hypoxemia (FiO2, PEEP) RSI Complications

Mort Study; N = 102Jaber Study; N = 251Schwartz Study; N = 238 Hypoxemia : 17%Hypoxemia: 26% Aspiration: 1.7%Aspiration: 4% Regurgitation: 4.4%Dental Injury: 1% Surgical Airway: 0.4%Pneumothorax: 1% Esophageal Intubation: 10% Esophageal Intubation: 4% Esophageal Intubation: 8% Bradycardia: 3.5%Severe Hemodynamic Collapse: 25% Cardiac Arrest: 2%Cardiac Arrest: 1%Cardiac Arrest/ Death 3% > 3 Attempts: 10%> 3 Attempts: 11% Mort TC J Clin Anesth 2004; 16: Schwartz DE Anesthesiology 1995; 82: Jaber S Crit Care Med 2006; 34:

Hypoxemia – Pt characteristics: ↓ FRC; PE, pleural effusion – Procedural: multiple attempts, poor preoxygenation Prevention/Management – Airway assessment and preparation – Preoxygenation – Mask ventilate if needed, 100% oxygen – Tube migration, kinking, or circuit disconnect – Bronchspasm, pneumothorax RSI Complications

RSI Complications: ↓Blood Pressure Jaber S Crit Care Med 2006; 34:

Sedation Complications Regurgitation/aspiration Hypoxemia Hypotension Uncooperative patient – Pain? – Anxiety? – Hypoxemia? – Dis-inhibition?

RSI and Sedation Complications and the Difficult Airway Algorithm

Airway assessment Basic airway management choices, determined by clinical situation Awake intubation: invasive or non-invasive

Initial attempt is unsuccessful

Cannot intubate, cannot ventilate

The Difficult Airway Airway assessment Ventilation possible vs impossible Always plan for multiple different techniques – esp. LMA Call for assistance early – Including surgical assistance Have surgical airway kits available

Conclusions Complications of RSI and sedation are similar Thorough airway assessment is a must Plan for intubation must be individualized Have back-up plans available Be sure equipment is working properly Call for help early if needed