TENSION PNEUMOTORAX IMAGENS PHISIOPATH .pdf

TENSION PNEUMOTORAX

1. Tension Pneumothorax
Simon Leigh-Smith
Emerg Med Consultant

Royal Infirmary Edinburgh
Defence Medical Services
MSc Resuscitation & Emergency Medicine
Queen Mary University London

2. 1
st
Interest

3. • + 20min
– <C> ?
– ABC Words
– D Confused
– E Pacing
• + 35min
– <C>ABCDE ??
– No response
– Sitting
14 YO boy

3 storey lift-shaft fall

4. 14 YO boy – 3 storey fall

+ 40min (on extrication)
• <C> / A ✔
• B
– BLUE FiO
2
0.21
– Dyspnoea++
0
words
– RR > 40
– SpO
2
un-recordable FiO
2
0.8
– Trachea central
– Bilateral normal air entry & resonance
– Bilateral crepitations
– Left Hypomobility & Hyper-expansion

• C - HR 140 & BP 140/70
• D – AVPU, Confused, occipital contusion, 4 limb movement ✔

5. 14 YO boy – 3 storey fall 

Treatment efficacy
• L Needle Thoracocentesis (2
nd
ICS MCL)
– Small hiss of air
– SpO
2
80%
– RR > 40
• L Finger Thoracostomy (5
th
ICS MAL)
– Huge expulsion of air
– SpO
2
90%
– RR 24
– Small amount of blood
• HR 100 / BP 120/60
• L Tube Thoracostomy (5
th
ICS MAL)
– SpO
2
95%

6. – Mum says
• “not as sharp as normal……….. seems a little bit slow
with his thinking…..”
14 YO boy – 3 storey fall
Outcome

7. Objectives

• 2 Diseases
– Mechanically Ventilated (MV) Decompensation
– Spontaneously Ventilating (SV) Compensatory period…...
• Hypoxic disease
– Respiratory demise in SV
– Cardiovascular demise in MV

• Diagnose then lateralise
• Revise ‘classical’ signs
• CXR / USS
• Decompression
– Considered decision
– NT / FT / TT

8. Pathophysiology

9. Physiology

Normal Respiratory
• Spont Vent
-5 to -8 cmH
2
0 (normal)
-80 cmH
2
0 (forced insp.)

• Mech Vent
+20 to +40 cm H
2
0

IPP

10. Pathophysiology

Pneumothorax
• Pneumothorax size changes
– Resolving
– Static
– Expanding

11. Evidence Base

12. Evidence Base

• Mechanically ventilated (MV)
– Animal experiments
– Case reports / series

• Spontaneously ventilating (SV)
– Animal experiments
– Case reports / series
• Post Mortem studies

13. Evidence Base

Pathophysiology Confounders
• Spontaneous
• Heimlich
• Traumatic
– MOI
– Confounders
• <C>
• # ribs (chest wall pain)
• Flail
• Pulmonary Contusion
• Haemothorax

14. Definition

15. Tension definition - inadequate
• Pneumothorax & iiBP
• Air “hiss” on needle thoracocentesis
• CXR
– mediastinal shift, diaphragmatic depression
• IPP (Ipsilateral)
– > atm / +ve
• throughout resp cycle
• at end expiration

16. Tension Definition - suggested
CLINICAL definition
• Pneumothorax with

significant improvement of vitals
on decompression alone

17. Incidence

18. Incidence
• Unknown
• Post Mortem studies
– 1 – 4%
• London HEMS patients (64% MV)
– 5.4%
• Needle thoracocentesis rates in PHEM services
– 0.7% - 30%
• Vietnam combat casualties
– 4% fatally wounded casualties died ‘with or from’ tension
– 0.3% PHEM cases in combat McPherson J Trauma 2006
Leigh-Smith J Trauma 2007

19. Mechanically Ventilated



Animal & Human Evidence


20. Animal Experiments – Mech Vent
• Dogs
Hilton 1925
Simmons 1958
Maloney 1961
Kilburn 1963

• Swine & Sheep
• Hypoxia & CVP rise
• iBP & hHR : 50% TLC
• Cardiovasc COLLAPSE: 90% TLC
• Death
Carvalho 1996
Barton 1999

21. Human Reports – Mech Vent
• Presentation
– Sudden at the point of DECOMPENSATION
– ii Sp02 - IMMEDIATE
–  ii BP
• Others
– Surgical emphysema
– hh HR
– (h ventilation pressure)
• Terminal
– Cardiovascular collapse (sudden)

22. Spontaneously Ventilating



Animal & Human evidence

23. Goats & sheep Rutherford 1968 / Gustman 1983 / Hurewitz 1986 / Bennet 1989

• COMPENSATORY MECHANISMS before “Tension”
– Minute Volume maintained
• hh RR
• hh TV

– Q / BP maintained
• –ve intra-thoracic P preserving venous return
• hh HR (compensating for i Stroke Vol)
• Rigid mediastinum
• Increased SVR
• Minimal evidence R sided venous obstruction
Animal Experiments – SV

24. • Pre-Terminal
– Progressive weakening of respiratory effort
– Decompensation secondary to
• Hypoxic
– Respiratory centre
– CVS centre
– Intercostal muscles
– Myocardium
• Restrictive ventilatory defect
• Decreased efficiency of flat diaphragm & stretched IC muscles
– Precipitous drop in minute volume @ ‘tension’
• Death = Resp arrest

Animal Experiments – SV

25. Animal Experiments – SV
IPP changes during development of TPT in SV goats (From Rutherford et al.)


+ve ipsilat. IPP
end exp.
+ve ipsilat. IPP
entire resp. cycle

26. Humans - SV
• COMPENSATORY PERIOD - VARIABLE
• Early & reliable
– Pleuritic Chest Pain
–  hh RR
–  hh HR
–  i Sp0
2
+/- Agitation

27. Humans - SV
• Pre-Terminal

–  ii RR
–  iii Sp0
2
– i BP
• But pp ??

28. Humans - SV
• Terminal
– Respiratory arrest


Crocker 1998 , Chest
Subotich D, Medical Hypotheses, 2005

29. Disease Lateralisation

30. Diagnosis – Lateralisation
IPSILATERAL

• SV (only)
– Hypo-expansion
• EARLY (if # ribs, pain)
• SV & MV
– Hyper-resonance
– Breath Sounds
• Decreased
• Added sounds (wheeze, creps)
– Hypo-mobility
– Hyper-expansion
• LATE & PATHOGNOMONIC
CONTRALATERAL

• SV (only)
– Hypermobility

31. Inconsistent Signs

32. Diagnosis

inconsistent signs
• Tracheal shift
Spiteri, Lancet 1988
• Distended neck veins
• (Cyanosis)
• Others

33. Imaging

34. Bob Pow Memorial Lecture 27 January 2012

35. Bob Pow Memorial Lecture 27 January 2012
•  CXR speed
•  Numbers taken
•  Diagnosis confirmation & lateralisation
•  Blind decompression complications
CXR in
Spont Vent

36. Bob Pow Memorial Lecture 27 January 2012
CXR
Features
Mediastinal deviation Vs clinical condition
Mediastinal deviation varies during respiration
Teplick, 1974
Greene, 1977
Clark , 2003

37. USS in diagnosis

38. Diagnostic Process

39. Bob Pow Memorial Lecture 27 January 2012
Diagnostic Process
• Consider
– Mechanism
– Index of Suspicion
– Mech Vent
• Low SpO
2

• Low BP
– Spont Vent
• Respiratory distress
• Confirm & lateralise
– Clinical Signs
– USS in PHEM
– CXR in ED (SV)

40. ATOM FC’s

41. (A)TOM FC

42. (A)TOM FC

…& tracheal deviation ✗ (No !)
pp
• chest injury
• shock
• dilated neck veins

• Tracheal deviation ??
• (Airway)
• Tension pneumothorax
• Open pneumothorax
• Massive haemothorax
• Flail chest
• Cardiac tamponade

43. (A)TOM FC

…hyper-expansion / USS ✔

pp
• chest injury
• severe tachypnoea
• Hyper-expansion
• Mobility (hyper/hypo)
• h Pn note
• i BS
• (Airway)
• Tension pneumothorax
• Open pneumothorax
• Massive haemothorax
• Flail chest
• Cardiac tamponade

44. Decompression Options

45. Decompression Options
• Tube
• Finger MV
• Needle

46. Needle Thoracocentesis

Complications
• Morbidity & MORTALITY
– Chest drain mandated
– Haemorrhage from major BVs
• Subclavian
• Mammary
• Intercostal
– Cardiac tamponade

47. Needle Thoracocentesis

Failure
• Not 100% NPV
– Needle length
• 4.5 cm venflon Vs ~ 30% ‘trauma patients’ > 5cm
• Venflon trocar alone is 7cm
– Obstruction
• blood / tissue / kinking
– Loculated tension
– Large air leak
• Actions on failure…...

48. Decompression Indications



(in SUSPECTED tension pneumothorax)

49. Indications for decompression

RELATIVE

• Respiratory distress
– Exclude anxiety +/- pain if possible
– Consistent & Progressive (2 min)
• Severe flail chest in SV
– RSI capable
• ? NT +/- TT è RSI
• ? RSI è FT
– RSI incapable = DIFFICULT !
• Tension or Flail dominant ?
• Chest signs / USS ?
• If in doubt - decompress

50. Indications for decompression

ABSOLUTE
DECOMPENSATION
MECH VENT

– SpO
2
< 92% on FiO
2
0.8
– Systolic BP < 90 mmHg
– Arrest
• Traumatic
• (Asthmatic)

DECOMPENSATION
SPONT VENT

– SpO
2
< 92% on FiO
2
0.8
– Systolic BP < 90 mmHg
– Severe Resp Distress
– Falling RR

51. Bob Pow Memorial Lecture 27 January 2012
Some Cases

Mech Vent

52. Bob Pow Memorial Lecture 27 January 2012
Some Cases

Spont Vent

53. 47 YOM

6m fall onto grass
• + 40min
• SOB
– RR 28
– Sp0
2
99% on FiO
2
0.8
• HR 120 & BP 130/80
• R side
– severe pleuritic CP
–  i BS
–  h resonance

54. 47 YOM

6m fall onto grass
• TT
– Air expulsion
• Exhalation
• Inhalation
• Vitals “improved”

55. 56 YOM 

Chronic Bronchitic

• Spont Pneumothorax
• No ‘tension’ on CXR
• BUT vitals monitored
during NT before TT:

56. 56 YOM 

Chronic Bronchitic
• Pre NT
– RR 34
– Sentences
– HR 130
– BP 220/130
– Sats 91% on FiO
2
0.8
• Post NT
– RR 20
– Paragraphs
– HR 110
– BP 130/80
– Sats 99% on FiO
2
0.8

57. 16 YOM 

Spontaneous Pneumothorax
• 0800hrs sudden
– SOB
– Pleuritic CP
• +5hrs 20min ED
– RR 40
– SpO
2
98% on FiO
2
0.8
– HR 90
– BP 130/80
– R side
• i BS
• h Resonance
• Hypomobility

58. 30 YOM 

Spontaneous Pneumothorax
• Sudden
• Severe pleuritic pain
• Restlessness
• + 5hrs 20min ED
– RR 22
– Sats 100% on FiO
2
0.8
– HR 80
– BP 130/60
• + 5hrs 50min Dr RV
– Trachea deviated to L
–  i BS on R
– CXR

59. 24 YOM

Cyclist Vs Car
• At Scene
– GCS 15
– LBP & SOB
• + 60min (into Helo)
– SpO
2
70% FiO
2
0.8
• + 100min – (in Flight)
– Increased SOB & CP
– Respiratory Arrest
• + 110min (in ED)
– Traumatic arrest resus
– Enormous gush of air on FT
– Died

60. Talk (gasp) & die….

61. doesn’t mean it isn’t time for a re-think !

62. Summary

• 2 Diseases
– Mechanically Ventilated Decompensation
– Spontaneously Ventilating Compensatory period…...
• Hypoxic disease
– Respiratory demise in SV
– Cardiovascular demise in MV

• Diagnose then lateralise
• Revise ‘classical’ signs
• CXR / USS Spontaneously Ventilating
• Decompression
– Considered decision
– NT / FT / TT

63. Bob Pow Memorial Lecture 27 January 2012
Questions?


Tension Pneumothorax – time for a re-think?
S Leigh-Smith, T Harris Emerg Med J 2005

Clinical Presentation of Patients with Tension Pneumothorax – A Systematic Review
D J Roberts, S Leigh-Smith et al Annals of Surgery 2014

Tension Pneumothorax: diagnosis and management.
www.bmjlearning.com

[email protected]