RESPIRATORY ASSESSMENT including blood gases, x-rays and outcome measures
(for exercise testing, see ‘Exercise’)

To convert: kPa ↔ mmHg -

NICE guidelines [CG50] Acutely ill adults in hospital: recognising and responding to deterioration (2007)

AARC CLINICAL PRACTICE GUIDELINE (2012): transcutaneous monitoring of carbon dioxide and oxygen. Respir Care, 57, 11, 1955-62

AARC (2013) CLINICAL PRACTICE GUIDELINE: blood gas analysis and hemoximetry. Respir Care; 58(10):1694-703




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Alba GA, Truong QA, Gaggin HK et al (2016) Diagnostic and prognostic utility of procalcitonin in patients presenting to the emergency department with dyspnea
online extra. Am J Med; 129(1):96–104.e7
• procalcitonin concentrations are higher in subjects with pneumonia
• in patients with acute dyspnea, procalcitonin is an accurate diagnostic marker for pneumonia

Albarrati AM, Gale NS, Enright S et al (2016) A simple and rapid test of physical performance in chronic obstructive pulmonary disease. Internat J COPD; 11:1785-1791. doi:10.2147/COPD.S106151

Albert TJ, Swenson ER (2016) Circumstances when arterial blood gas analysis can lead us astray. Respir Care; 61(1):119-21. doi: 10.4187/respcare.04556

Anderson J (2016) Step tests are safe for assessing functional capacity in patients hospitalized with acute lung diseases. J Cardiopulmon Rehabilit Prevention; 36(1):56- 61

Andersen LW, Kim WY, Chase M et al (2016) The prevalence and significance of abnormal vital signs prior to in-hospital cardiac arrest (American Heart Association's Get With the Guidelines) Resuscitation; 98:112-7. doi: 10.1016/j.resuscitation.2015.08.016
• abnormal vital signs are prevalent 1-4 hours before an in-hospital cardiac arrest

Ansari BM, Zochios V, Falter F et al (2016) Physiological controversies and methods used to determine fluid responsiveness: a qualitative systematic review. Anaesthesia; 71:94–105. doi: 10.1111/anae.13246

Baldwin CE, Paratz JD, Bersten AD (2013) Muscle strength assessment in critically ill patients with handheld dynamometry: an investigation of reliability, minimal detectable change, and time to peak force generation. J Crit Care, 1, 77-86. doi: 10.1016/j.jcrc.2012.03.001

Beekman E, Mesters I, Hendriks EJM et al (2013) Course length of 30 metres versus 10 metres has a significant influence on six-minute walk distance in patients with COPD: an experimental crossover study. J Physiother, 59(3)169-176

Bennett S, Bruton A, Barney A et al (2015) The relationship between crackle characteristics and airway morphology in COPD. Respir Care; 60(3):412-421

Benton D (2011) Dehydration influences mood and cognition: a plausible hypothesis? Nutrients, 3, 5, 555–73

Birring SS, Prudon B, Carr AJ et al (2003) Development of a symptom specific health status measure for patients with chronic cough. Thorax, 58, 339-43.

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Bordoni B, Marelli F, Morabito B et al (2016) Manual evaluation of the diaphragm muscle. Int J Chron Obstruct Pulmon Dis; 11:1949-56. doi: 10.2147/COPD.S111634

Bruusgaard D, Tschudi-Madsen H, Ihlebæk C et al (2012) Symptom load and functional status: results from the Ullensaker population study. BMC Public Health, 12: 1085. doi: 10.1186/1471-2458-12-1085

Carlsten C, Aitken ML, Hallstrand TS (2007) Safety of sputum induction with hypertonic saline solution in exercise-induced bronchoconstriction. Chest; 131(5):1339–44

Chanques G et al (2006) Impact of systematic evaluation of pain and agitation in an intensive care unit. Crit Care Med, 34, 6, 1691-9
• accurate assessment of pain and agitation reduces duration of mechanical ventilation and hospital-acquired infections

Chanques G, Pohlman A, Kress JP et al (2014) Psychometric comparison of three behavioural scales for the assessment of pain in critically ill patients unable to self-report. Crit Care; 18:R160 doi:10.1186/cc14000

Chatterjee M, Ge X, Kostov Y et al (2015) A rate-based transcutaneous CO2 sensor for noninvasive respiration monitoring. Physiol Meas; 36(5):883-94. doi: 10.1088/0967-3334/36/5/883
• noninvasive CO2 monitoring as accurate as arterial blood gases

Cheuvront SN (2013) Physiologic basis for understanding quantitative dehydration assessment. Am J Clin Nutr; 97(3):455-462. doi:10.3945/ajcn.112.044172

Connolly MA (2001) Black, white and shades of gray: common abnormalities in chest radiographs. AACN Clin Issues, 12, 259-69;jsessionid=D48oT8PdT9msfbUhDRFB24d3SZbnLeBWhzqhIKW51KXDWJZeGiVZ!-477899252!-949856144!9001!-1?index=1&database=ppvovft&results=1&count=10&searchid=1&nav=search (abstract only)
• systematic examination, common abnormalities, examples

Corner EJ, Handy JM, Brett SJ (2016) eLearning to facilitate the education and implementation of the Chelsea Critical Care Physical Assessment: a novel measure of function in critical illness. BMJ Open; 6(4):e010614. doi: 10.1136/bmjopen-2015-010614.

Cortés CA, Martínez RM (2013) Manifestations of lobar atelectasis on chest X-rays and correlation with computed tomography findings. Radiologia. 56;(3):257–267. doi:10.1016/j.rx.2013.08.003

Costa R, Almeida N, Ribeiro F (2015) Body position influences the maximum inspiratory and expiratory mouth pressures of young healthy subjects Physiotherapy; 101(2): 239–241 doi:10.1016/

Cowley NJ, Owen A (2013) Interpreting arterial blood gas results. BMJ, 346, f16

Dale DC (2016) How I diagnose and treat neutropenia. Curr Opin Hematol; 23(1):1-4. doi: 10.1097/MOH.0000000000000208

Davis AHT (2007) Reliability and validity of the Exercise Self-regulatory Efficacy Scale for individuals with COPD. Heart Lung, 36, 3, 205-16

Davidson WJ, Dennis J, The S et al (2014) Identification and validation of nebulized aerosol devices for sputum induction. Can Respir J; ;21(2):101-6

Desborough MJ, Keeling DM (2013) How to interpret a prolonged prothrombin time or activated partial thromboplastin time. Br J Hosp Med, 74, 1, C10-C12

Dick E (2000) Chest x rays made easy. Student BMJ, 89, 444-6

Dicpinigaitis PV, Lim L, Farmakidis C (2014) Cough syncope. Respir Med; 108(2):244-251

DiLibero J, O'Donoghue SC, DeSanto-Madeya S et al (2016) An innovative approach to improving the accuracy of delirium assessments using the Confusion Assessment Method for the intensive care unit. Dim Crit Care Nurs; 35(2): 74- 80

Doyle JF, Schortgen F (2016) Should we treat pyrexia? And how do we do it? Crit Care; 20: 303. doi: 10.1186/s13054-016-1467-2
• the concept of pyrexia as a protective physiological response to aid in host defence has been challenged with the awareness of the severe metabolic stress induced by pyrexia.

Farkhooy A (2013) Impaired Carbon Monoxide Diffusing Capacity is the strongest predictor of exercise intolerance in COPD. COPD, 10(2):180–185. doi:10.3109/15412555.2012.734873

Fortis S, Corazalla EO, Qi W et al (2015) The difference between slow and forced vital capacity increases with increasing body mass index: a paradoxical difference in low and normal body mass indices. Respir Care; 60(1):113-118

Frerichs I, Amato MBP, van Kaam AH et al (2017) Chest electrical impedance tomography examination, data analysis, terminology, clinical use and recommendations. Thorax; 72(1): 83-93

Garcia-Pachon E (2002) Paradoxical movement of the lateral rib margin (Hoover sign) for detecting obstructive airway disease. Chest, 122, 651-5
• Hoover sign is easy to recognise and useful for detecting obstructive airway disease

Gilbert M (2013) Cardiac output measurement. Anaesth Int Care Med, 14(2):63-67

Grosbois J, Riquier C, Chehere B et al (2016) Six-minute stepper test: a valid clinical exercise tolerance test for COPD patients. International J COPD; 11:657-663. doi: 10.2147/COPD.S98635.

Guenther U, Weykam J, Andorfer U (2012) Implications of objective vs subjective delirium assessment in surgical intensive care patients. Am J Crit Care, 21, e12-e20; doi:10.4037/ajcc2012735

Hajian B, Backer J, Vos W et al (2016) Functional respiratory imaging (FRI) for optimizing therapy development and patient care. Expert Rev Respir Med; 60(5):740-3. doi: 10.4187/respcare.03457
• functional imaging techniques offer the possibility of visualising lobe volumes and airflow distribution in three dimensions

Hammond K, You D, Collins EG et al (2013) Life-threatening hypokalemia following rapid correction of respiratory acidosis. Heart Lung; 42(4)287-289

Hansen KB, Westin J, Andersson LM et al (2016) Flocked nasal swab versus nasopharyngeal aspirate in adult emergency room patients: similar multiplex PCR respiratory pathogen results and patient discomfort. Infect Dis (Lond); 48(3):246-50. doi: 10.3109/23744235.2015.1096956
• flocked nasal swab might be preferable in certain settings and situations

Heavens KR, Charkoudian N, O’Brien C et al (2016) Noninvasive assessment of extracellular and intracellular dehydration in healthy humans using the resistance-reactance–score graph method. Am J Clin Nutr; 103:724-729. doi:10.3945/ajcn.115.115352

Ikematsu Y (2007) Incidence and characteristics of dysphoria in patients with cardiac tamponade. Heart Lung, 36, 6, 440-9.

Inoue H (2009) A new breath-holding test may noninvasively reveal early lung abnormalities caused by smoking and/or obesity. Chest, 136, 2, 545-553
• the fall in SaO2 during a 20-second breath-hold at resting end-exhalation reveals early lung abnormalities

Irwin Z, Cook JO (2016) Advances in point-of-care thoracic ultrasound. Emerg Med Clin; 34(1): 151–157. doi:

Jácome C, Marques A (2017) Computerized respiratory sounds: novel outcomes for pulmonary rehabilitation in COPD. Respir Care; 62(2):199-208

Jain SN (2011) A pictorial essay: radiology of lines and tubes in the intensive care unit. Indian J Radiol Imaging, 21, 3, 182–190.

Janssen R, Wang W, Moço A et al (2016) Video-based respiration monitoring with automatic region of interest detection. Physiol Meas; 37(1):100-14. doi: 10.1088/0967-3334/37/1/100

Jones PW (2013) COPD Assessment Test – rationale, development, validation and performance. COPD, 10(2): 269-271. doi:10.3109/15412555.2013.776920

Jones AYM, Jones RD (2000) The effect on sound generation of varying both gas flow rate and the viscosity of sputum-like gel. Lung, 178, 31-40
• absence of crackles does not always indicate absence of secretions

José A, Dal Corso S (2016) Step tests are safe for assessing functional capacity in patients hospitalized with acute lung diseases. J Cardiopulm Rehabil Prev; 36(1):56-61. doi: 10.1097/HCR.0000000000000149

Jubran A (2015) Pulse oximetry. Crit Care; 19:272. doi: 10.1186/s13054-015-0984-8

Karbing DS, Kjaergaard S, Smith BW et al (2007) Variation in the PaO2/FiO2 ratio with FiO2: mathematical and experimental description, and clinical relevance. Crit Care, 11:R118
• PaO2/FiO2 quantifies effects of treatment
• PaO2/FiO2 varies with both FiO2 and SaO2
• classifies patients' gas exchange status, including definitions of ALI (27 kPa ≤ PaO2/FiO2 < 40 kPa) and ARDS (PaO2/FiO2 < 27 kPa)
(useful commentary on how this measurement can achieve a balance between accuracy and feasibility is on

Kaur R, Prabhakar A, Kochhar S et al (2015) Blunt traumatic diaphragmatic hernia: Pictorial review of CT signs. Indian J Radiol Imaging; 25(3):226-32. doi: 10.4103/0971-3026

Khan AN, Al-Jahdali H, Al-Ghanem H (2009) Reading chest radiographs in the critically ill. Ann Thorac Med; 4(2):75–87

Kusmirek JE, Martin MD, Kanne JP (2016) Imaging of idiopathic pulmonary fibrosis. Radiol Clin N Am; 54(6):997–1014

Kusmirek JE, Martin MD, Kanne JP (2016) Imaging of idiopathic pulmonary fibrosis. Radiol Clin N Am; 54(6):997–1014. httpdx.doi.org10.1016j.rcl.2016.05.004

Kvale A, Johnsen TB, Ljunggren AD (2002) Examination of respiration in patients with long-lasting musculoskeletal pain. Advances Physiother, 4, 169-81
• fascinating insight into the effect of pain on breathing

Lakhe A, Sodhi I, Warrier J et al (2016) Development of digital stethoscope for telemedicine. J Med Eng Technol; 40(1):20-4. doi: 10.3109/03091902.2015.1116633

Lange NE (2009) Spirometry: don't blow it! Chest, 136, 2, 608-614
• everything you need to know about the practicalities of spirometry.

Langridge PJ, Sheehan RL, Denning DW (2016) Microbial yield from physiotherapy assisted sputum production in respiratory outpatients. BMC Pulm Med. doi: 10.1186/s12890-016-0188-2

Laouani A, Rouatbi S, Saguem S et al (2016) Thorax and abdomen motion analysis in patients with obstructive diseases. J Pulm Respir Med; 6:313. doi:10.4172/2161-105X.1000313

Leech M, Bissett B, Kot M et al (2015) Physiotherapist-initiated lung ultrasound to improve intensive care management of a deteriorating patient and prevent intubation: a case report. Physiother Theory Pract; 31(5):372-6. doi: 10.3109/09593985.2014.1003629
• (pleural effusion could also be picked up with percussion note and vascular markings visible through the density on x-ray)

Lermuzeaux M, Meric H, Bertrand Sauneuf B et al (2016) Superiority of transcutaneous CO2 over end-tidal CO2 measurement for monitoring respiratory failure in nonintubated patients: A pilot study. J Crit Care; 31(1):150–156. doi:
• PtcCO2 is more accurate than ETCO2

Magnet FS, Windisch W, Storre JH (2016) Monitoring of pCO2 during ventilation. Med Klin Intensivmed Notfmed; 111(3):202-7. doi: 10.1007/s00063-016-0150-3

Malaguti C (2009) Reliability of chest wall mobility and its correlation with pulmonary function in patients with Chronic Obstructive Pulmonary Disease. Respir Care, 54, 12, 1703-11

Manali ED (2010) MRC chronic dyspnea scale: Relationships with cardiopulmonary exercise testing and 6-minute walk test in idiopathic pulmonary fibrosis patients. BMC Pulm Med, 10, 32

Marques A, Cruz J, Quina S et al (2016) Reliability, agreement and minimal detectable change of the Timed Up & Go and the 10-Meter Walk Tests in older patients with COPD. COPD; 13(3): 279-287. doi: 10.3109/15412555.2015.1079816

McSwain SD, Yeager BE (2015) Is there an easy, effective, efficient, and inexpensive technique to reduce pain of arterial punctures? Respir Care; 60(1):141-143. doi: 10.4187/respcare.03865.
• the ‘significant morbidity’ of taking ABGs can be prevented by gels, ice packs or painfree jet injections:

Miravitlles M, Kruesmann F, Haverstock D et al (2012) Sputum colour and bacteria in chronic bronchitis exacerbations: a pooled analysis. Eur Respir J; 39(6):1354-1360. doi:10.1183/09031936.00042111

Morélot C, Gilet H, Aguilaniu B et al (2016) Real-life assessment of the multidimensional nature of dyspnoea in COPD outpatients. Eur Respir J; 47(6):1668-79. doi: 10.1183/13993003.01998-2015

Muñoz M, Gómez-Ramírez S, Kozek-Langeneker S (2016) Pre-operative haematological assessment in patients scheduled for major surgery. Anaesthesia; 71 Suppl 1:19-28. doi: 10.1111/anae.13304

Nakada TA, Masunaga N, Nakao S et al (2016) Development of a prehospital vital signs chart sharing system. Am J Emerg Med; 34(1):88-92. doi: 10.1016/j.ajem.2015.09.048

Pasterkamp H, Brand PL, Everard M, Garcia-Marcos L et al (2016) Towards the standardisation of lung sound nomenclature. Eur Respir J; 47(3):724-32. doi: 10.1183/13993003.01132-2015

Patel MJ (2016) Cardiopulmonary exercise tests in patients with heart failure and chronic obstructive pulmonary disease: moving beyond risk assessment. JACC Heart Fail; 4(4):262-4. doi: 10.1016/j.jchf.2016.02.005

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Persichini R, Gay F, Schmidt M et al (2016) Diagnostic accuracy of respiratory distress observation scales as surrogates of dyspnea self-report in intensive care unit patients. Anesthesiology; 123(4):830-7. doi: 10.1097/ALN.0000000000000805

Pianosi PT, Zhang Z, Hernandez P et al (2016) Measuring dyspnea and perceived exertion in healthy adults and with respiratory disease: new pictorial scales. Sports Medicine - Open; 2:17. doi:10.1186/s40798-015-0038-4

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Pinsky M, Clermont G, Hravnak M (2016) Predicting cardiorespiratory instability. Crit Care; 20:70

Poulose V, Tiew PY, How CH (2016) Approaching chronic cough. Singapore Med J; 57(2):60-3. doi: 10.11622/smedj.2016028

Richardson M, Purssell E et al (2015) Who’s afraid of fever? Arch Dis Child; 100(9):818-820. doi:10.1136/archdischild-2014-307483
• Fever is a natural response to infection, some microorganisms being adversely affected and some defence mechanisms performing better at higher body temperatures

Rushton M, Smith J (2016) How to measure blood pressure manually. Nurs Stand; 30(21):36-9. doi: 10.7748/ns.30.21.36.s43

Sandhu PK, Bajaj D, Mehta K (2016) Correlation of peak expiratory flow rate with age and anthropometric parameters in elderly (>65 years) Natl J Physiol Pharm Pharmacol; 6(1): 89-92. doi: 10.5455/njppp.2015.5.0104201584

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Schmidt PE, Meredith P, Prytherch DR et al (2015) Impact of introducing an electronic physiological surveillance system on hospital mortality. BMJ Qual Saf; 24:10-20. doi:10.1136/bmjqs-2014-003073
• technology-assisted early-warning scores reduce mortality

See KC, Ong V, Wong SH et al (2016) Lung ultrasound training: curriculum implementation and learning trajectory among respiratory therapists. Int Care Med; 42(1):63–71

Sellarés J, Hernández-González F, Lucena CM et al (2016) Auscultation of velcro crackles is associated with usual interstitial pneumonia. Medicine (Baltimore); 95(5):e2573. doi: 10.1097/MD.0000000000002573

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Stieglitz S, Matthes S, Priegnitz C (2016) Comparison of transcutaneous and capillary measurement of pCO in hypercapnic subjects. Respir Care; 61(1): 98-105
• PtcCO2 is useful for monitoring hypercapnic patients at night.

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Swigris JJ et al (2017) Psychometric properties of the St George's Respiratory Questionnaire in patients with idiopathic pulmonary fibrosis.
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Tehrany R, Bruton A, Barney A (2016) The feasibility of recording speech breathing patterns before and after pulmonary rehabilitation in an out- patient environment. J Pulm Respir Med 6:318. doi:10.4172/2161-105X.1000318
• breathing pattern to assess work of breathing

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Ursprung E, Oren-Grinberg A (2016) Point-of-care ultrasound in the perioperative period. Int Anesthesiol Clin; 54(1):1-21. doi: 10.1097/AIA.0000000000000084

Vafaei A, Hatamabadi HR, Heidary K et al (2016) Diagnostic accuracy of ultrasonography and radiography in initial evaluation of chest trauma patients. Emerg (Tehran); 4(1):29-33

van Oppen JD, Daniel PS, Sovani MP (2015) What is the potential role of transcutaneous carbon dioxide in guiding acute noninvasive ventilation? Respir Care; 60(4):484-91. doi: 10.4187/respcare.03335
• transcutaneous CO2 monitoring provides a continuous and reliable alternative to repeated arterial blood gas sampling, and also allows pH prediction

Vasilevskis EE, Pandharipande PP, Graves AJ et al (2016) Validity of a Modified Sequential Organ Failure Assessment Score using the Richmond Agitation-Sedation Scale. Crit Care Med; 44(1):138-46. doi: 10.1097/CCM.0000000000001375

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• behavioural pain scale

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6MD = 6-minute distance
AARC = American Association for Respiratory Care
ACPRC = Association of Chartered Physiotherapists in Respiratory Care
CVD = cardiovascular disease
ETCO2 = end-tidal CO2 monitor
HCO3− = bicarbonate ion concentration
HF = heart failure
HR = heart rate
IPPV = intermittent positive pressure ventilation
JAMA = Journal of American Medical Association
MI = myocardial infarction
SOB = shortness of breath
SpO2 = saturation of haemoglobin taken by pulse oximeter
VO2 max = maximum oxygen consumption