Top Banner
Updates on Asthma and COPD Keng Sheng Chew School of Medical Sciences Universi6 Sains Malaysia 1
33

Updates on Asthma and COPD

May 07, 2015

Download

Health & Medicine

Chew Keng Sheng

Presented during the 1st Malaysian National Emergency Critical Care Symposium in Ipoh, Perak, Malaysia, Nov 2013.
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Page 1: Updates on Asthma and COPD

Updates  on  Asthma  and  COPD  

Keng  Sheng  Chew  School  of  Medical  Sciences  

Universi6  Sains  Malaysia  

1  

Page 2: Updates on Asthma and COPD

Conflict  of  Interest  

•  I  declare  I  have  received  educa6onal  grants  from  Astra-­‐Zeneca  (M)  Sdn  Bhd  

2  

Page 3: Updates on Asthma and COPD

Outlines  

•  In  asthma:    •  Con6nuous  neb?  •  IV  B2-­‐agonist?    •  IV  steroids?  •  An6cholinergics?  •  Magnesium  sulphate?  

•  NIPPV?  •  When  intubate?  What  to  look  for?  

3  

Page 4: Updates on Asthma and COPD

Outlines  

•  In  COPD:  •  Recent  concepts  •  B2-­‐agonists  vs  an6cholinergics?  •  NIPPV?  •  Issues  of  mechanical  ven6la6on  

•  Hypoxic  drive  –how  true  is  this  fear?  

4  

Page 5: Updates on Asthma and COPD

Updates  on  Asthma  

5  

Page 6: Updates on Asthma and COPD

Pathophysiology  of  Asthma  

6  

Page 7: Updates on Asthma and COPD

Pathological  changes  

7  

Page 8: Updates on Asthma and COPD

“Rules  of  2”  in  asthma  

•  AXacks  >2  6mes  per  week  or  •  Needs  rescuer  inhaler  >2  6mes  per  week  

•  Awakening  due  to  nocturnal  symptoms  >2  6mes  per  month  

•  Use  >2  canisters  of  relievers  per  year  •  If  yes  to  any  =  uncontrolled,  needs  steroids  

•  (Adapted  from  GINA  guideline)  

8  

Page 9: Updates on Asthma and COPD

Con@nuous  neb  vs  intermiCent  neb?  

•  “Con6nuous”  neb  =  con6nuous  aerosol  delivery  or  sufficient  frequency  of  at  least  1  neb  q15  min  or  >  4  neb/hour  

•  In  a  Cochrane  systema6c  review,  Camargo  et  al  (2009),  8  trials,  n  =  461  

•  Con@nuous  neb  – Benefits  in  severe  disease  – Significant  lung  improvement  at  2  –  3  hours  – Similar  side  effects  (tremors,  increased  K+,  HR)  

– Well  tolerated  9  

Page 10: Updates on Asthma and COPD

IV  Beta-­‐2  agonists  vs  inhaled  Beta-­‐2  agonists?  

•  Travers  et  al  (2001),  in  a  Cochrane  systema6c  review,  15  trials,  n  =  583  

•  IV  beta  agonists  offer  no  therapeu6c  advantage  over  inhaled  forms  of  the  drugs.    

•  However,  no  difference  in  autonomic  side  effects  

10  

Page 11: Updates on Asthma and COPD

Early    IV  steroids  use?  

•  Rowe  et  al  (2009),  Cochrane  systema6c  review,  12  trials,  n  =  863  

•  IV  steroids  given  within  1  hour:  •  significantly  reduced  admission  rates  (OR  =  0.40,  95%  CI:  0.21  to  0.78)  

•  Benefits  most  pronounced  among  those  with  severe  asthma  and  in  those  who  have  not  yet  been  on  systemic  steroids  prior  to  ED  presenta6on  

11  

Page 12: Updates on Asthma and COPD

An@cholinergics  

•  An6cholinergics  –  not  to  be  used  alone  •  Teoh  et  al  (2012),  in  a  Cochrane  review,  4  trials,  n  =  171  – An6cholinergics  alone  less  efficacious  and  more  likely  to  fail  

•  An6cholinergics  combined  with  SABA?  – Griffiths  et  al  (2013),  in  a  systema6c  review,  15  trials,  n  =  2497  (pediatrics),  found  

– combining  an6cholinergic  and  SABA  significantly  reduces  the  risk  for  hospital  admission  

12  

Page 13: Updates on Asthma and COPD

Magnesium  sulphate  

•  Blocks  calcium  channel  •  Relaxes  bronchial  smooth  muscle  •  Inhibits  contrac6le  response  to  endogenous  bronchoconstrictors  

•  Rowe  et  al  (2009):  •  7  trials,  n  =  665  •  Overall  no  improvement  in  lung  func6on,  no  improvement  in  adm  rate  

•  BUT  reduce  admission  rate  in  severe  asthma  subgroup  

13  

Page 14: Updates on Asthma and COPD

NIPPV  in  Asthma?  

•  Lim  et  al  (2012)  in  a  Cochrane  review,  5  trials,  n  =  206,  preliminary  results  show  NIPPV  has  benefit  of  –  Reduced  hospitaliza6on  rate  –  Reduced  6me  to  discharge  from  ED  –  Improves  lung  func6on  

•  But  s6ll  lack  of  good  evidence,  remains  controversial;  NOT  for  rou6ne  use  

•  Two  of  the  studies:  2  intuba6ons  needed  in  45  par6cipants  on  NPPV  vs  no  intuba6ons  in  41  control  pa6ents  (risk  ra6o  4.48;  95%  CI  0.23  to  89.13)  

14  

Page 15: Updates on Asthma and COPD

Mechanical  ven@la@on  

•  4  indica6ons  for  intuba6on  (Brenner  et  al,  2009  in  Proceedings  of  the  ATS)  –  cardiac  arrest  –  respiratory  arrest  or  profound  bradypnea  –  physical  exhaus6on  – AMS  (agitated  pa6ent,  interfering  with  oxygen  delivery)    

•  Hypercapnia  per  se  without  evidence  of  physical  exhaus6on  or  mental  changes  IS  NOT  an  indica6on  

•  Persistent  hypercapnia  despite  treatment  +/-­‐  AMS  is  an    indica6on  (PaCO2  increase  ~  5mmHg/Hr  or  more  than  55  –  70  mmHg)  

15  

Page 16: Updates on Asthma and COPD

Mechanical  ven@la@on  

•  Permissive  hypercapnia  -­‐  minimize  risk  of  increased  intrathoracic  pressure.  Ini6al  sepng:  – TV  6  ml/kg  – Rate  6/min  –  I:E  up  to  1:4  

•  Try  keep  Plateau  pressure  below  30  cm  H20.    

•  Pplat  (or  lung  distension  pressure)  gives  an  es6mate  of  average  of  end-­‐insp  alveolar  P  (Brenner  et  al,  2009)  

16  

Page 17: Updates on Asthma and COPD

Induc@on  Agents  

•  Ketamine    •  releases  of  catecholamines  

•  bronchial  smooth  muscle  relaxa6on  

•  Side  effects  –  hypersecre6on,  hypertension,  arrhythmias,  and  hallucina6ons  

•  rela6vely  contraindicated  in  pa6ents  with  ischemic  heart  disease,  hypertension,  increased  intracranial  pressure.   17  

Page 18: Updates on Asthma and COPD

Updates  on  COPD  

18  

Page 19: Updates on Asthma and COPD

Reversible Irreversible

Source: Peter J. Barnes, MD

Page 20: Updates on Asthma and COPD

Basics  

•  COPD  is  a  systemic  disease,  not  just  pulmomary  (Agus6,  2005)  – systemic  inflamma6on,  systemic  oxida6ve  stress,  ac6va6on  of  circula6ng  inflammatory  cells,  e.g.  neutrophils,  macrphages,  and  augmented  levels  of  pro-­‐inflammatory  cytokines  

•  Extrapulmonary  associa6ons:  IHD,  osteopenia,  cachexia,  malnutri6on,  skeletal  was6ng  

20  

Page 21: Updates on Asthma and COPD

Bronchodilators  

•  Cochrane  systema6c  review  by  McCrory  et  al  (2005)  – No  significant  difference  in  changes  in  FEV1  between  b2-­‐agonists  and  the  an6cholinergic  ipratropium  at  90  minutes  and  24  hours  and    

–  no  advantage  combining  

•  An6cholinergics  –  slower  onset  (15  min,  peak  60  to  90  min,  and  longer  6  to  8  hrs).  

•  General  consensus  (GOLD)  –  SABA  first,  then  an6cholinergics  

21  

Page 22: Updates on Asthma and COPD

NIPPV  in  COPD  

•  Ram  FSF  et  al  (2004)  in  a  Cochrane  systema6c  review,  14  trials  involving  n  =  622  (outcomes  of  treatment  failure),  n  =  541  (mortality)  

•  NIPPV  resulted  in  •  decreased  mortality    

•  decreased  need  for  intuba6on    •  reduc6on  in  treatment  failure  

22  

Page 23: Updates on Asthma and COPD

Mechanical  ven@la@ons  

•  Issues  with  mechanical  ven6la6on  in  COPD  (BruloXe  et  al,  2012):  

•  poorer  prognosis  (mortality  rates  between  20%  and  73%)    

•  a  mean  life  expectancy  of  1  year  

•  Barotrauma,  infec6ons  

•  Discuss  with  family  regarding  pros  and  cons  

23  

Page 24: Updates on Asthma and COPD

Hypoxic  Drive  in  COPD?  

•  How  real  is  this  fear?  •  Started  off  with  a  paper  by  E.J.M  Campbell  in  1960    

•  Really  no  science  behind  it!  Consensus  opinion  

•  A  Cochrane  review  by  Aus6n  Wood-­‐Baker  (2009)  –  “No  relevant  trials  have  been  published  to  date,  so  there  is  no  evidence  to  indicate  whether  different  oxygen  therapies  in  the  pre-­‐hospital  se@ng  have  an  effect  on  outcome  for  people  with  acute  exacerbaBons  of  COPD”  

24  

Page 25: Updates on Asthma and COPD

Hypoxic  Drive  in  COPD?  

•  Plant  et  al  (2000)  shows  an  associa6on  between  increased  oxygen  with  hypercapnea,  respiratory  acidosis,  and  ICU  admission  but  this  does  not  occur  in  every  pa6ent  given  increased  FiO2.  

•  May  happen  

•  Careful  observa6on  of  this  pa6ent  •  BUT  remember:  the  risks  of  withholding  oxygen  are  much  greater  than  giving  them  too  much!  

25  

Page 26: Updates on Asthma and COPD

Summary  

•  In  asthma:    •  Con6nuous  neb?  •  IV  B2-­‐agonist?    •  IV  steroids?  •  An6cholinergics?  •  Magnesium  sulphate?  

•  NIPPV?  •  When  intubate?  What  to  look  for?  

26  

Page 27: Updates on Asthma and COPD

Summary  

•  In  COPD:  •  Recent  concepts  •  B2-­‐agonists  vs  an6cholinergics?  •  NIPPV?  •  Issues  of  mechanical  ven6la6on  

•  Hypoxic  drive  -­‐  controversials  

27  

Page 28: Updates on Asthma and COPD

References  •  Camargo  Jr  CA,  Spooner  C,  Rowe  BH.  Con6nuous  

versus  intermiXent  beta-­‐agonists  for  acute  asthma.  Cochrane  Database  of  Systema6c  Reviews  2003,  Issue  4.  Art.  No.:  CD001115.  DOI:  10.1002/14651858.CD001115  

•  Travers  A,  Jones  AP,  Kelly  K,  Barker  SJ,  Camargo  CA,  Rowe  BH.  Intravenous  beta2-­‐agonists  for  acute  asthma  in  the  emergency  department.  Cochrane  Database  Syst  Rev.2001;(2)  :CD002988  

•  Rowe  BH,  Spooner  C,Ducharme  F,  Bretzlaff  J,  BotaG.  Early  emergency  department  treatment  of  acute  asthma  with  systemic  cor6costeroids.  Cochrane  Database  of  Systema6c  Reviews  2001,  Issue  1.  Art.  No.:  CD002178.  DOI:  10.1002/14651858.CD002178.  

28  

Page 29: Updates on Asthma and COPD

References  

•  Griffiths  B,  Ducharme  FM.  Combined  inhaled  an6cholinergics  and  short-­‐ac6ng  beta2-­‐agonists  for  ini6al  treatment  of  acute  asthma  in  children.  Cochrane  Database  of  Systema6c  Reviews  2013,  Issue  8.  Art.  No.:  CD000060.  DOI:  10.1002/14651858.CD000060.pub2.  

•  Lim  WJ,  Mohammed  Akram  R,  Carson  KV,  Mysore  S,  Labiszewski  NA,  Wedzicha  JA,  Rowe  BH,  Smith  BJ.  Non-­‐invasive  posi6ve  pressure  ven6la6on  for  treatment  of  respiratory  failure  due  to  severe  acute  exacerba6ons  of  asthma.  Cochrane  Database  of  Systema6c  Reviews  2012,  Issue  12.  Art.  No.:  CD004360.  DOI  10.1002/14651858.CD004360.pub4.   29  

Page 30: Updates on Asthma and COPD

References  

•  Barry  Brenner,  Thomas  Corbridge,  and  Antoine  Kazzi  "Intuba6on  and  Mechanical  Ven6la6on  of  the  Asthma6c  Pa6ent  in  Respiratory  Failure",  Proceedings  of  the  American  Thoracic  Society,  Vol.  6,  No.  4  (2009),  pp.  371-­‐379.    

•  McCrory  DC,  Brown  CD.  An6cholinergic  bronchodilators  versus  beta2-­‐sympathomime6c  agents  for  acute  exacerba6ons  of  chronic  obstruc6ve  pulmonary  disease.  Cochrane  Database  of  Systema6c  Reviews  2003,  Issue  1.  Art.  No.:  CD003900.  DOI:10.1002/14651858.CD003900.  

30  

Page 31: Updates on Asthma and COPD

References  

•  Agus6  AG.  Systemic  effects  of  chronic  obstruc6ve  pulmonary  disease.  Proc  Am  Thorac  Soc  2005;  2  (4):367-­‐70;  discussion  71-­‐2.    

•  Ram  FSF,  Picot  J,  Lightowler  J,  Wedzicha  JA.  Non-­‐invasive  posi6ve  pressure  ven6la6on  for  treatment  of  respiratory  failure  due  to  exacerba6ons  of  chronic  obstruc6ve  pulmonary  disease.  Cochrane  Database  of  Systema6c  Reviews  2004,  Issue  3.  Art.  No.:  CD004104.  DOI:  10.1002/14651858.CD004104.pub3.    

•  BruloXe  CA,  Lang  ES.  Acute  exacerba6ons  of  chronic  obstruc6ve  pulmonary  disease  in  the  emergency  department.  Emerg  Med  Clin  North  Am.  2012;  May;30(2):223-­‐47,  vii.  

31  

Page 32: Updates on Asthma and COPD

References  

•  Teoh  L,  Cates  CJ,  et  al.  An6cholinergic  therapy  for  acute  asthma  in  children.  Cochrane  Database  Syst  Rev  2012,  Issue  4:  CD003797.  

•  Plant  PK,  Owen  JL,  Elliot  MW.  One  year  period  prevalence  study  of  respiratory  acidosis  in  acute  exacerba6ons  of  COPD:  implica6ons  for  the  provision  of  noninvasive  ven6la6on  and  oxygen  administra6on.  Thorax  2000;55:550–4.  

32  

Page 33: Updates on Asthma and COPD

33