CVR Physiotherapy › Technique cards › Scales and investigations
Investigations: chest X-ray, PFT, ECG and bedside tests
Investigations are asked as 3-mark questions (X-ray of pleural effusion, emphysema, COPD and tetralogy of Fallot; PFT in obstructive and restrictive disease; ECG criteria for MI; ABI) and they are the spots in the practical exam (chest X-ray, ABG, PFT, ECG). Learn a fixed order for reading each one and the physiotherapy meaning of each finding.
- Syllabus
- Ch 2(a) Investigation and clinical implication: X-ray, PFT, ABG, ECG, ABI, claudication time, pulses, auscultation, postural hypotension
- Priority
- High yield. 3-mark questions in most papers, and four of the five practical spots.
- Asked as
- 7m W24 (ABG, PFT, X-ray in COPD) 3m S16W18S19W19W20S21S24W24
- Usual split
- 3-mark findings; practical spots
- Checked against
- ERS/ATS interpretive strategies for lung function tests (2022); consensus definition of orthostatic hypotension (2011); Fourth Universal Definition of MI (2018); standard chest radiograph and ECG interpretation. Full list under Sources.
- Content checked
- 19 October 2026. Next review due October 2027.
- My revision
-
1Chest X-ray
A fixed order for reading
- Details and quality: name, date, PA or AP (AP films, taken in bed, make the heart look bigger); rotation (the spinous processes sit midway between the clavicle ends); inspiration (about 6 anterior or 10 posterior ribs above the right diaphragm); exposure.
- A, Airway: trachea central or shifted.
- B, Breathing (lungs and pleura): compare left and right zone by zone; lung markings reaching the edge; pleural lines; costophrenic angles sharp.
- C, Cardiac: heart size (cardiothoracic ratio below 0.5 on a PA film), borders, mediastinum.
- D, Diaphragm: the right is usually slightly higher; flattened in hyperinflation; free air under it.
- E, Everything else: bones (fractures, sternal wires), soft tissues (surgical emphysema), lines and tubes.
Silhouette sign: when a white area touches a border and blurs it, it lies next to that border. Loss of the right heart border means right middle lobe disease; loss of a hemidiaphragm means lower lobe disease.
| Finding | What you see | Physio meaning |
|---|---|---|
| Consolidation | White area with air bronchograms; volume kept | Early pneumonia: positioning and mobility; airway clearance only when sputum is retained |
| Collapse (atelectasis) | White, smaller lobe; fissure, trachea and mediastinum pulled towards it; raised hemidiaphragm | Target that lobe: positioning, deep breaths with a hold, airway clearance |
| Pleural effusion | Dense white base with a concave upper edge (meniscus); blunted costophrenic angle; large ones push the mediastinum away | Lie on the good side, thoracic expansion; drainage first if large |
| Pneumothorax | Black area with no lung markings beyond a thin pleural line; tension: mediastinum pushed away | No positive-pressure techniques until drained; tension is an emergency |
| Hyperinflation (COPD) | Dark lungs, flat diaphragms, more than 6 anterior ribs visible, narrow heart | Forward-lean positions, pursed-lip breathing; bullae mean no high pressures |
| Pulmonary oedema | Haziness spreading from both hila ("bat's wing"), Kerley B lines, large heart, effusions | Sit up; no airway clearance for oedema fluid |
| Interstitial lung disease | Fine net-like (reticular) shadows at the bases, small lungs | Expect exercise desaturation: oxygen during training |
| Bronchiectasis | Thick-walled airways seen as tram lines and ring shadows | Daily airway clearance for the affected lobes |
| Lung abscess | Round cavity with an air–fluid level | Drainage with the abscess uppermost; never the good lung down if it may spill |
| Lines and tubes | Endotracheal tube tip a few cm (about 5) above the carina; nasogastric tube below the diaphragm; chest drain in the pleural space | A tube in the right main bronchus collapses the left lung; check before treating |
Condition-specific films: emphysema and COPD on the COPD page; pleural effusion and pneumothorax on the pleural page; tetralogy of Fallot (boot-shaped heart) on the congenital page.
2Pulmonary function tests
| Measure | Meaning |
|---|---|
| FVC | The total volume blown out as hard and fast as possible after a full breath in |
| FEV1 | The volume blown out in the first second |
| FEV1/FVC | Normally about 0.75–0.80 in adults; low in obstruction |
| PEF | Peak expiratory flow: the fastest flow; used for home asthma diaries |
| TLC, RV, FRC | Lung volumes (body box or gas dilution): high in hyperinflation, low in restriction |
| DLCO | Diffusing capacity: low in emphysema, ILD and pulmonary vascular disease; normal in asthma |
| Pattern | FEV1 | FVC | FEV1/FVC | TLC | Examples |
|---|---|---|---|---|---|
| Obstructive | Low | Normal or low | Low (below 0.70, or below the lower limit of normal) | Normal or high | COPD, asthma, bronchiectasis |
| Restrictive | Low | Low | Normal or high | Low (needed to confirm) | ILD, pleural thickening, kyphoscoliosis, obesity, neuromuscular weakness, after lung resection |
| Mixed | Low | Low | Low | Low | Post-TB lung disease, cystic fibrosis |
- Bronchodilator response: traditionally an FEV1 or FVC rise of at least 12% and 200 mL after salbutamol (ATS/ERS 2005); the 2022 ERS/ATS standard uses a rise of more than 10% of the predicted value. Large responses suggest asthma.
- Flow–volume loop: a "scooped" (concave) expiratory curve in obstruction; a small, narrow loop in restriction; flattening in upper airway obstruction.
- Peak flow variability through the day supports asthma; a personal best guides the action plan.
- Read the S25 case: FVC 60%, FEV1 82%, FEV1/FVC 94% predicted: both volumes reduced with a high ratio, so restrictive (old TB scarring).
Severity grading in COPD (GOLD 1–4 by FEV1 % predicted) is on the COPD page; the spirometry curves are drawn on the COPD page.
3ECG
Basics
- Paper speed 25 mm a second: one small square = 0.04 s, one large square = 0.2 s; 10 mm = 1 mV.
- P wave = atria depolarise; QRS = ventricles depolarise; T wave = ventricles repolarise.
- Normal intervals: PR 0.12–0.20 s (3–5 small squares); QRS below 0.12 s (under 3 small squares); QTc below about 0.44 s in men and 0.46 s in women.
- Heart rate: 300 ÷ number of large squares between two R waves (regular rhythm), or the number of QRS complexes in a 10-second strip × 6 (irregular rhythm).
- Order: rate, rhythm (regular?), P before every QRS?, PR, QRS width, ST and T changes.
Rhythm strips to recognise (simplified)
| Rhythm or finding | Key features | Physiotherapy action |
|---|---|---|
| Sinus tachycardia | Normal beats above 100 | Look for a cause (pain, fever, anaemia, low fluid, anxiety); resting rate above 120: postpone exercise |
| Sinus bradycardia | Normal beats below 60 | Common with beta-blockers and in fit people; stop if dizzy or the BP falls |
| Atrial fibrillation | No P waves; irregularly irregular | Exercise if the rate is controlled; use RPE, not heart rate; anticoagulants mean bleeding risk |
| Ectopic beats | Early extra beats; ventricular ones are wide | Occasional ones are harmless; frequent, multiform or in runs during exercise: stop |
| Ventricular tachycardia | Fast, wide, regular complexes | Emergency: check pulse, call for help; if no pulse, start CPR |
| Ventricular fibrillation | Chaotic line, no QRS | Cardiac arrest: CPR and defibrillation (see the BLS card) |
| Heart block | First degree: PR above 0.20 s. Second degree: some P waves not followed by QRS (Mobitz I: PR lengthens then a beat drops; Mobitz II: beats drop suddenly). Third degree: P and QRS unrelated | First degree and Mobitz I: usually safe. Mobitz II and third degree: no exercise until treated (pacemaker) |
| ST elevation or depression | Elevation in neighbouring leads: acute MI; depression: ischaemia | New changes: stop and report (criteria on the IHD page) |
| Paced rhythm | Sharp pacing spikes before the P wave or QRS | Device precautions; heart rate may not rise normally |
4Bedside cardiovascular tests
| Test | How | Interpretation |
|---|---|---|
| Pulses | Feel both sides: radial, brachial, carotid (one side at a time), femoral, popliteal, dorsalis pedis, posterior tibial | Graded 0 absent, 1+ weak, 2+ normal, 3+ bounding (some scales go to 4+). A weak or absent foot pulse suggests arterial disease (S21 case: popliteal 1+) |
| Postural (orthostatic) hypotension | BP after 5 minutes lying, then at 1 and 3 minutes of standing | A sustained fall of 20 mmHg or more systolic or 10 mmHg or more diastolic within 3 minutes (consensus, 2011). Common after bed rest, with diuretics and antihypertensives, in diabetes and spinal cord injury |
| Ankle–brachial index (ABI) | Doppler pressures at both ankles and both arms; highest ankle ÷ highest arm, for each leg | 0.91–1.40 normal, 0.90 or less PAD, below 0.40 severe; above 1.40 calcified arteries (full table on the PAD page) |
| Claudication distance or time | Treadmill at a fixed speed and gradient (often 3.2 km/h at 12%), or a graded protocol, or a 6-minute walk | Record the pain-free (initial) claudication distance and the maximal walking distance; used to set and review the walking programme |
| Capillary refill | Press a nail bed for 5 seconds, release | Colour should return within about 2–3 seconds; slower suggests poor circulation or shock |
| Auscultation | Breath sounds and added sounds | See the chest signs card |
| ABG | Arterial sample | See the ABG card |
5Exam corner
Past questions (MUHS, 2016–2026)
- 3-mark questionsRadiological findings of pleural effusion (S16). Radiological findings of emphysema (W18). Three spirometric findings in restrictive lung disease (S19). PFT findings in COPD (W19). PFT in obstructive lung disease (W20). Radiological features of tetralogy of Fallot (S21). ECG criteria for acute and evolved MI (S24). X-ray findings in COPD (W24). ABI (S17, W18, S23, S24, W25, S26).
- 7-mark questionRelevance of ABG, PFT and X-ray in decision-making for goal setting in COPD (W24; COPD page).
- Practical examSpots: chest or cardiac X-ray, ABG, PFT, ECG and devices (5 × 2 marks); see the practical exam card.
Test yourself
3 mGive three X-ray signs of a left lower lobe collapse.
A triangular white shadow behind the heart (the "sail sign"); loss of the medial part of the left hemidiaphragm outline (silhouette sign); raised left hemidiaphragm and the mediastinum shifted slightly to the left; smaller left lung.
3 mFEV1 45% predicted, FVC 80% predicted, FEV1/FVC 0.45, with only a small change after salbutamol. Interpret.
Obstructive pattern (low ratio), severe by FEV1 (GOLD 3, 30–49%), with little reversibility: typical of COPD.
MCQAn ECG shows a regular rhythm with 4 large squares between R waves. The heart rate is:A. 50B. 75C. 100D. 150
B. 300 ÷ 4 = 75 beats a minute.
MCQPostural hypotension is a fall within 3 minutes of standing of at least:A. 10 mmHg systolicB. 20 mmHg systolic or 10 mmHg diastolicC. 40 mmHg systolicD. 5 mmHg diastolic
B. 20 mmHg systolic or 10 mmHg diastolic.
Sources
- MUHS BPTh syllabus (2012) and MUHS IV BPTh question papers 2016–2026 (muhsonline.com, unofficial archive; Dhole Patil College of Physiotherapy past-paper page).
- Stanojevic S, et al. ERS/ATS technical standard on interpretive strategies for routine lung function tests. Eur Respir J 2022;60:2101499. Pellegrino R, et al. Interpretative strategies for lung function tests. Eur Respir J 2005.
- Freeman R, et al. Consensus statement on the definition of orthostatic hypotension, neurally mediated syncope and the postural tachycardia syndrome. Clin Auton Res 2011;21:69–72.
- Thygesen K, et al. Fourth Universal Definition of Myocardial Infarction. Circulation 2018.
- Gerhard-Herman MD, et al. 2016 AHA/ACC guideline on the management of patients with lower extremity peripheral artery disease (ABI interpretation).
- Structure and classical content: Corne & Kumaran, Chest X-Ray Made Easy; Hampton, The ECG Made Easy; Hough, Physiotherapy in Respiratory and Cardiac Care.
Educational notes for exam preparation. Not medical advice.
Version 1. Content checked 19 October 2026. Next review October 2027.