ETT Placement confirmationprediction of post extubation stridor, Successful Extubation & Diaphagramatic Function

Dr. Dinakara PrithvirajChief Neonatalogist & pediatric intensivistVydehi institute of medical sciences& RC

For Next Generation

Introduction

• Emergency sonography in Pediatrics has evolved to become one of the most versatilemodalities for diagnosing and guidingtreatment of critically ill patients.

• It complements rather than replacestraditional sonology.

Why we need to learn doing U/S inPediatrics

• It is usually not feasible to have a cardiologist orsonographer available on immediate call on a 24-h basis.

• Allows the ability to perform serial bedsideexaminations and allows the important assessment and reassessment of the adequacy and efficacy of therapy.

ACEP/ SCCM guidelines includeUSG by Pediatricians

In critically ill patients physical examination is quitelimited and inaccurate.• USG has potential to reinvigorate physical exam,improving accuracy.• Important attributes: portability, lack of radiation,repeatability, absence of consumables, being battery powered , plus Information can be stored fordocumentation, transmission & consultation.

Remember• USG may appear complex at first sight butsimply requires a change in thinking.

• Once the process has been learned, a step bystep use will make it a routine

Remember

• Inappropriate interpretation or application of data gained by a poorly skilled user may have adverse consequences.

• So adequate training is essential and this must beindividualized and tailored to the specific needsand applications of the user.

AIRWAY ULTRASOUND

Trachea

AIRWAY ULTRASOUND

Trachea

Tube in Esophagus

2 Signals Bad

Transverse View Showing ETT

Longitudinal View Showing ETT

ETT Position Assesment with Ultrasound

• Proximal ETT Malposition (ETT too High)-Measure distance from vocal cord to tip of the tube-Tip of tube should not be visible above sternal notch• Distal ETT Malposition-Unilateral pleural sliding may indicate mainstem intubation -Combination of both may eleminate the need for chest x-ray (Study Underway)

Laryngeal Ultrasound-An useful method in predicting post extubation stridor

• Identifying patients at high risk for Re-intubation due to stridor

-Cuff-leak test: was widely used but its application is limited due to controversial result

-The air-column width during deflation is a potential predictor of post extubations stridor

• Air column during balloon calf inflation(hyper echoic)

• True cords are over both the side of air column(Hypo-echoic)

• Cartilages are behind the true vocal cords & beside the air column (hyper echoic)

• Air column during balloon-cuff deflation

-Air column width increased

-This patient did not develop post extubation stridor

• Air column during baloon cuff defletion-air column width increasedThis patient did not develop post extubation stridor

• Air column during baloon cuff inflation(hyper echoic)

• True cords are over both side of the air column(hypoechoic)

• Cartilages are behind the true vocal cords and beside the air column (hyper echoic)

LARYNGEAL ULTRASOUND:An USEFUL METHOD IN PREDICTING POST EXTUBATION STRIADOR

• The air column width during calf deflation is a potential predictor of post extubation stridor

Can you extubate this patient?

Diaphragmatic Movement evaluation with Thorasic Ultrasound

• Thoracic ultrasound-lack of ionizing radiation-bedside procedure-should be the method of choice in the investigation of suspected hemidiaphgramatic movement abnormality• Proposed technique-changes in diaphragm thickness during contraction-chronically paralyzed diaphragm is atrophic and doesn't thicken during inspiration(contraction)

Diagnosis of Diaphgramatic Paralysis• Chest Radiograph-Elevated hemidiaphragm & atelectasis• Fluoroscopy-requires patient transportation-uses iniozing radiation-sniff test:paradoxical elevation of paralyzed hemidiaphragm with inspiration(>90%)

Diaphragmatic Paralysis• Unilateral vs bilateral• Increase in load on the other respiratory accessory muscle-respiratory failure• Clinical manifestations• -DOE,orthopnoea• -Rapid shallow breathing• Paradoxical abdominal wall retraction during inspiration• Hypoxemia due to atelectasis• Hypercapnoea & hypoxemia• Severe cases (Ventilatory failure, severe pulmonary

hypertension, secondary erythrocytosis)

Challanges• During DB, descending lung may obscure the

diaphragm -The probe should be displaced caudally with angle adjustment to maintain a perpendicular approach of the hemi diaphragmatic motion• Patients with respiratory disease and dysonoea-increased respiratory effort can result in greater chest wall movement and cause the ribs & lung to obscure the images• Visualization of the left hemidiaphragm is recognised

as more difficult due to the smaller window of the spleen as compared with the liver window

Diaphragmatic Movement & contractility evaluation by thoracic ultrasound

• Always identify the diaphragm• Don’t confuse the hepato renal pouch or

spleen renal recess for diaphragm• Sub diaphragmatic device insertion may have

lethal effect• Exercise particular caution in post CABG cases• Unilateral diaphragmatic dysfunction

Probe position for dome movement

DIAOHGRAM MOVEMENT AND CONTRACTILITY EVALUATION BY THORASIC ULTRASOUND

Diaphragmatic Paralysis: The use of M Mode Ultrasound for Diagnosis in Adult

• Normal diaphragm-Sniff test: sharp upstroke(normal caudal movement of the diaphragm during inspiration)

• Diaphragmatic Paralysis-No active caudal movement of the diaphragm with inspiration-sniff test: abnormal paradoxical movement (cranial movement on inspiration)

Manoever begun at the end of normal expiration

• Quiet Breathing(QB):-Diaphragm excursion(inspiratory amplitude)1.5-2 cm-lower limit for women 0.9 cm-lower limit for men 1 cm

• Voluntary Sniffing (VS)-Diaphragm excursion(inspiratory amplitude)2.5-3cmLower limit for women 1.6cmLower limit for men 1.8cmNormal caudal movement (sharp upstroke)of the diaphragm during inspiration

• Deep Breathing(DB)Diaphragm excursion (inspiratory amplitude) 6-7cm-lower limit ofor woman 3.7 cm-lower limit for men 4.7 cm

Diaphragmatic Paralysis: The Use of M mode ultrasound for diagnosis in adult

• Sniff Test• -Normal DiaphragmSharp upstroke (normal caudal movement of diaphragm during inspiration)

-Diaphragmatic Paralysis No caudal movement of diaphragm with inspirationAbnormal paradoxical cranial movement on inspiration

2

Ultrasonography Diagnostic criterion for severe diaphragmatic dysfunction after CABG

• After cardiac surgery-surgery related phrenic nerve injury

-severe diaphragmatic dysfunction can prolong mechanical ventilation

-(US)probe is positioned on right mid-axillary line

-Diaphragmatic excursion measured from the end of normal expiration(c) to end of maximal inspiratory effect (D)

Ultrasonography Diagnostic criterion for severe diaphragmatic dysfunction after cardiac surgery

• Best E< 25 mm was associated with severe diaphragmatic dysfunction

• None of the patients with uncomplicated post operative course have best E< 25mm, either before or after surgery

• Excellent negative likehood ratio of best E<25 mm

Paralysis weakness

Probe position for diaphragm muscle thickness

1. MOTION

2. AMPLITUDE

3.FORCE OF VELOCITY

Thickness inspiratory - thickness expiratory

WEAKNESS

PARALYSIS

LOW AMPLITUDE

PARADOXICAL MOVEMENT1.Can follow up with US

2.If phrenic nerve damage or paralysis

- Prolonged ventilation needed

4.THICKNESSthickness expiratory

TF[2.3]=

inspiratory[25mm]

expiratory [17mm]

Post operative diaphragm Amplitude maximum inspiration should be >25 (good)Weaning from ventilation – liver/spleen 1.1 cm displacement

1.Successful extubation-(a). Amplitude >25mm (b).TDI % >30%2. D/D (a) weakness (b) paralysis 3.Follow up of diapgramatic motion strength

Ventilation and Asynchrony

Ventilation and synchrony

CONCLUTION• M mode ultrasonography is a relatively simple and

accurate test for diagnosing paralysis of diaphragm

• Diaphragmatic function assessment with ultrasound is important in patients with prolonged ventilation

• Ultrasonography should be considered to exclude severe diaphragmatic dysfunction following cardiac surgery in daily practice with the advantages of being fully non invasive & easilty available in ICU

Remember• USG may appear complex at first sight butsimply requires a change in thinking.

• Once the process has been learned, a step bystep use will make it a routine

Remember cont..

• Inappropriate interpretation or application of data gained by a poorly skilled user may have adverse consequences.

• So adequate training is essential and this must beindividualized and tailored to the specific needsand applications of the user.

Lung Ultrasound Ready for Prime TimeIt is for you