| Anatomical structures | |
| anterior junction line (on an x-ray) | AJL |
| aortic arch | AA |
| azygos vein | AV |
| blood-brain barrier | BBB |
| bronchopleural | BP |
| caudal ventral respiratory group neurons | cVRG |
| cerebrospinal fluid | CSF |
| costophrenic angle | CPA |
| cranial nerves IX, X, etc | CN-IX, CN-X |
| descending (or dorsal) aorta | DA |
| dorsal respiratory group neurons | DRG |
| ductus arteriosus, patent | PDA |
| extracellular fluid | ECF |
| foramen ovale (patent) | FO (PFO) |
| inferior vena cava | IVC |
| infrahilar window (on a lateral chest x-ray) | IH |
| laryngotracheoesophageal cleft | LTEC |
| left atrium | LA |
| left diaphragm | LD |
| left interlobar pulmonary artery | LIPA |
| left mainstem bronchus | LMB |
| left pulmonary artery | LPA |
| left upper lobe of the lung | LUL |
| left ventricle | LV |
| lower respiratory tract | LRT |
| nucleus tractus solitarii | NTS |
| periciliary layer of aqueous or "sol" | PCL |
| phalangeal joints: distal inter-, proximal inter- | DIP, PIP |
| phalangeal joint, metacarpo- | MCP |
| posterior costophrenic angle (on lateral x-rays) | PCPA |
| proximal left pulmonary artery | PLPA |
| pulmonary artery | PA |
| pulmonary vein | PV |
| rapidly adapting receptor(s) | RAR(s) |
| retrosternal space (as on an x-ray) | RS |
| right atrium | RA |
| right diaphragm | RD |
| right interlobar pulmonary artery | RIPA |
| right paratracheal stripe (on an AP x-ray) | RPS |
| right pulmonary artery | RPA |
| right upper lobe of the lung | RUL |
| right ventricle | RV (regrettably, same as residual volume) |
| rostral ventral respiratory group neurons | rVRG |
| slowly adapting stretch receptor(s) | SAR(s) |
| superior vena cava | SVC |
| trachea | TRA (on an x-ray) |
| tracheoesophageal fistula(e) | TEF |
| upper respiratory tract | URT |
|
| Biologicals, chemicals, cells, cytokines, and reagents | |
| activated clotting Factor V | Factor Va |
| alpha1 proteinase inhibitor | α1-PI |
| angiotensin converting enzyme | ACE |
| argon (inert gas) | Ar |
| ATP-binding cassette protein member A3 gene | ABCA3 |
| bicarbonate anion | HCO−3 |
| bone morphogenetic protein receptor type 2 | BMPR2 |
| brain natriuretic peptide | BNP |
| carbohydrate recognition domain(s) | CRD(s) |
| carbon dioxide | CO2 |
| carbon monoxide | CO |
| carbonic acid | H2CO3 |
| carbonic anhydrase | CA |
| chloride anion | Cl− |
| concentration of substance "Xy" | [Xy] (units in parentheses) |
| dipalmitoyl phosphatidylcholine, in surfactant | DPPC |
| epidermal growth factor | EGF |
| erythropoietin | EPO |
| ferric iron, as in methemoglobin | Fe3+ |
| ferrous iron, as in hemoglobin | Fe2+ |
| granulocyte colony-stimulating factor | G-CSF |
| granulocyte macrophage colony-stimulating factor | GM-CSF |
| helium (inert gas) | He |
| helium-oxygen breathing mixture | Heliox |
| hydroxyl radical | ·OH |
| hypochlorite ion | OCl− |
| immunoglobulins A, E, G, M | IgA, IgE, IgG, IgM |
| insulin-like growth factor-1 | IGF-1 |
| interleukin 1β, 6, 8, 10, etc | IL-1β, IL-6, IL-8, IL-10 |
| kilodaltons (of molecular weight) | KDa |
| lamellar bodies (of surfactant) | LB |
| long-acting β2-adrenergic receptor agonist(s) | LABA(s) |
| low-molecular weight heparin | LMWH |
| membrane spanning domains | MSD |
| molecular weight (or mass) | MW |
| muscarinic type 3 (receptors) | M3 |
| myoglobin | Mb |
| neuron-specific enolase | NSE |
| neutrophil(s), polymorphonuclear | PMN(s) |
| nitric oxide | NO |
| nitric oxide synthase (inducible) | NOS (iNOS) |
| nonsteroidal anti-infl ammatory drug(s) | NSAID(s) |
| normal sterile saline (0.9% NaCl) | NS |
| nucleotide binding domain(s) | NBD(s) |
| oxygen, molecular | O2 |
| peroxynitrite | ONOO− |
| phosphatidylethanolamine, in surfactant | PEt |
| phosphatidylglycerol, in surfactant | PG |
| phosphatidylinositol, in surfactant | PI |
| phosphatidylserine, in surfactant | PS |
| platelet activating factor | PAF |
| platelet-derived growth factor | PDGF |
| proton, free as in acid solution | H+ or [H+] |
| purified protein derivative (for TB skin test) | PPD |
| reactive nitrogen species | RNS |
| reactive oxygen species | ROS |
| recombinant tissue plasminogen activator | rt-PA |
| sex hormone binding globulin-1 | SHBG-1 |
| superoxide anion | ·O−2 |
| surfactant associated proteins A, B, C, D | SP-A, SP-B, SP-C, SP-D |
| technetium, radiolabeled | 99Tc (most common radioisotope) |
| transforming growth factor-beta | TGF-β |
| tumor necrosis factor-alpha | TNF-α |
| 2,3-diphosphoglycerate | 2,3-DPG |
| unfractionated heparin | UFH or UF Heparin |
| xenon, inert gas, radiolabeled | 133Xe (most common radioisotope) |
|
| Blood, RBC, and hemoglobin-related | |
| carbaminohemoglobin | HbCO2 |
| carboxyhemoglobin | HbCO |
| hemoglobin A, F, S, etc | Hb-A, Hb-F, Hb-S |
| hematocrit or packed red cell volume | hct (%) |
| hemoglobin concentration in blood | [Hb] (g/dL or g%) |
| mean red cell hemoglobin concentration | MCHC (%) |
| mean red cell hemoglobin content | MCH (pg/cell) |
| mean red cell volume | MCV (fL or μm3) |
| methemoglobin | metHb |
| oxygen dissociation curve | ODC |
| pH, arterial or mixed venous | pHa, pHv̄ |
| red blood cell(s) | RBC(s) |
| red cell count in whole blood | #RBC/μL |
|
| Diagnostic techniques, procedures, professional entities, and locations |
| acid-fast bacillus (organisms), stain | AFB, AFB stain |
| activated partial thromboplastin time | aPTT (sec) |
| adaptive support servo-ventilation | ASV |
| American College of Sports Medicine | ACSM |
| American Thoracic Society (guidelines, etc) | ATS |
| anteriorñposterior or anteroposterior (as a view) | AP |
| anti-neutrophil cystoplasmic antibody (study) | ANCA |
| arterial blood gas sample | ABG(s) |
| average volume-assured pressure support vent | AVAPS |
| bilevel positive airway pressure ventilation | BiPAP |
| bronchoalveolar lavage (fluid) | BAL (BALF) |
| Centers for Disease Control and Prevention | CDC |
| colony-forming unit(s), as of bacteria | CFU |
| computed tomography | CT |
| continuous positive airway pressure ventilation | CPAP |
| directly observed therapy (as for TB treatment) | DOT |
| electrocardiogram, electrocardiography | ECG |
| emergency room, emergency department | ER, ED |
| Environmental Protection Agency | EPA |
| European Respiratory Society (guidelines, etc) | ERS |
| extracorporeal membrane oxygenation | ECMO |
| fluorescence polarization | FP |
| foam stability index (of surfactant) | FSI |
| fractional excretion of nitric oxide | FeNO |
| genioglossus advancement + hyoid myotomy + suspension | GAHMS |
| Global Initiative for Obstructive Lung Disease | GOLD |
| high resolution computed tomography | HRCT |
| immunoreactive trypsinogen | IRT |
| inspiratory positive airway pressure ventilation | IPAP |
| intensive care unit | ICU |
| international normalized ratio (for coag assays) | INR |
| laser-assisted uvulopalatoplasty | LAUP |
| lecithin/sphingomyelin ratio (amniotic) | L/S |
| likelihood ratio, positive or negative | +LR, −LR |
| lower limit(s) of normal range | LLN |
| magnetic resonance imaging, functional | MRI, fMRI |
| mechanical ventilation | MV |
| [methacholine] inducing a 20% decline in FEV1 | PC20 |
| National Asthma Education & Prevention Program | NAEPP |
| National Health & Nutrition Examination Survey III | NHANES-III |
| non-invasive positive pressure ventilation | NIPPV |
| parts per billion (as for a rare gas species) | ppb |
| periodic acid-Schiff (reagent stain) | PAS |
| positron emission spectrometry | PET |
| positive end-expiratory pressure | PEEP |
| positive pressure during expiration ventilation | EPAP |
| posterior to anterior (as a view) | PA |
| Prospective Investigation of Pulmonary Embolism Diagnosis Trial | PIOPED Trial |
| prothrombin time | PT (sec) |
| pulmonary arterial catheter (Swan-Ganz) | PAC |
| pulmonary function test or testing(s) | PFT(s) |
| rapid shallow breathing index | RSBI |
| spontaneous breathing trial | SBT |
| saturation with oxygen, arterial by oximetry | Sao2 (%) |
| saturation with oxygen, mixed venous by oximetry | Sv̄o2 (%) |
| sustained-release (medications) | SR |
| transjugular intrahepatic portosystemic shunt | TIPS |
| uvulopalatopharyngoplasty | UPPP |
| ventilation/perfusion lung scan | V/Q scan |
| video-assisted thoracoscopic surgery | VATS |
| World Health Organization | WHO |
|
| Diseases, conditions, and syndromes | |
| acute interstitial pneumonia | AIP |
| acute lung injury | ALI |
| acute mountain sickness | AMS |
| acute respiratory distress syndrome | ARDS |
| allergic bronchopulmonary aspergillosis | ABPA |
| benign asbestos pleural effusion | BAPE |
| bronchopulmonary dysplasia | BPD |
| carcinoma in situ | CIS |
| central sleep apnea | CSA |
| Cheyne-Stokes respiration | CSR |
| chronic obstructive pulmonary disease | COPD |
| coal worker's pneumoconiosis | CWP |
| community-acquired pneumonia | CAP |
| complete blood count | CBC |
| complex sleep apnea syndrome | CompSAS |
| congenital cystic adenomatoid malformation | CCAM |
| congenital central alveolar hypoventilation syndrome | CCAHS |
| congestive heart failure | CHF |
| cryptogenic organizing pneumonia | COP |
| cystic fibrosis | CF |
| cystic fibrosis-related diabetes mellitus | CFRDM |
| deep vein (or venous) thrombosis | DVT |
| desquamative interstitial pneumonitis | DIP |
| diffuse alveolar damage (a pathology diagnosis) | DAD |
| diffuse alveolar hemorrhage (a clinical diagnosis) | DAH |
| disseminated intravascular coagulation | DIC |
| distal intestinal obstruction syndrome | DIOS |
| environmental tobacco smoke | ETS |
| Epstein-Barr virus | EBV |
| heparin-induced thrombocytopenia | HIT |
| high altitude pulmonary edema | HAPE |
| human immunodeficiency virus | HIV |
| human papilloma virus | HPV |
| idiopathic pulmonary fibrosis | IPF |
| interstitial lung disease(s) | ILD(s) |
| Lambert-Eaton myasthenic syndrome | LEMS |
| lymphangioleiomyomatosis | LAM |
| lymphoid interstitial pneumonia | LIP |
| methicillin-resistant Staphylococcus aureus | MRSA |
| multiple drug resistant-organism | MDR-organism |
| multiple organ dysfunction syndrome | MODS |
| Mycobacterium avium complex | MAC |
| Mycobacterium tuberculosis | MTB |
| neonatal respiratory distress syndrome | neonatal RDS or nRDS |
| nonspecific interstitial pneumonia | NSIP |
| obesity-hypoventilation syndrome | OHS |
| obstructive sleep apnea | OSA |
| occupational asthma | OA |
| patent ductus arteriosus | PDA |
| patent foramen ovale | PFO |
| progressive massive fibrosis | PMF |
| pulmonary alveolar proteinosis | PAP |
| pulmonary arterial hypertension | PHT |
| pulmonary embolism, emboli | PE |
| respiratory bronchiolitis-interstitial lung disease | RB-ILD |
| respiratory syncytial virus | RSV |
| sleep-related hypoventilation/hypoxemic syndrome | SRH |
| squamous cell carcinoma | SCCA |
| syndrome of inappropriate antidiuretic hormone hypersecretion | SIADH |
| systemic inflammatory response syndrome | SIRS |
| systemic lupus erythematosus | SLE |
| thrombotic thrombocytopenic purpura | TTP |
| tuberculosis | TB |
| usual interstitial pneumonia | UIP |
| venous thromboembolism | VTE |
| ventilator-associated lung injury | VALI |
| ventilator-associated pneumonia | VAP |
|
| Physiological functions, processes, and measurements | |
| acute hypoxic pressor response | AHPR |
| alveolar capillary endothelial surface area | SC (in cm2 or m2) |
| alveolar epithelial surface area | SA (in cm2 or m2) |
| alveolar septal barrier thickness, harmonic mean | τs (in μm) |
| alveolar ventilation rate | V̇A (L/min) |
| alveolar ventilation/perfusion ratio | V̇A/Q̇ (dimensionless) |
| anterior-posterior axis or direction (as an x-ray) | AP |
| apnea-hypopnea index | AHI (scorable events/h) |
| blood transfer conductance coefficient for CO | ΘCO |
| body mass index, equal to weight/(height)2 | BMI (in SI units, kg/m2) |
| body temperature/pressure (37°C, PB,100% RH) | BTPS |
| carbon dioxide production rate | V̇Aco2 (mL/min or L/h) |
| cardiac output | Q̇ (L/min) |
| compliance, as of lung tissue or vasculature | ΔV/ΔP (mL or L/mm Hg or cm H2O) |
| dead space ventilation rate | V̇D (L/min) |
| diffusivity, Krogh's coefficient for gas x | DX |
| exercise-induced arterial hypoxemia | EIAH |
| filtration coefficient of permeability | K |
| fractional composition of gas "Xy" | FXy (a decimal from 0.0 to 1.0) |
| lung diffusive capacity for CO | DLCO |
| maximal oxygen consumption rate | V̇o2max (mL/min or L/h) |
| membrane diffusive capacity for CO | DMCO |
| oxygen consumption rate | V̇o2 (mL/min or L/h) |
| peak expiratory fl ow (rate) | PEF(R) (mL or L/sec) |
| polysomnogram | PSG |
| protein reflection coefficient (Starling's equation) | σ(range = 0.0 – 1.0) |
| pulmonary vascular resistance | PVR (mm Hg/L/min) |
| rapid eye movement sleep, or non relative humidity | REM, NREM RH (%) |
| respiratory disturbance index | RDI (scorable events/h) |
| respiratory effort-related arousal(s) | RERA(s) |
| respiratory quotient | R |
| shunt fraction of cardiac output | Q̇S/Q̇T(%) |
| six-minute walk test | 6-MWT |
| standard temperature/pressure (0°C, 1 atm, dry) | STPD |
| surface tension, as in alveolus | T |
| systemic vascular resistance | SVR (mm Hg/L/min) |
| total ventilation rate, also "minute ventilation" | V̇E (L/min) |
| viscosity, as of a gas in Poiseuille equation | η |
|
| Pressure (all types, in mm Hg or cm H2O) | |
| airway, critical opening | PCO |
| airway, if "intratracheal" preferred | PIT |
| airway, normal internal | PAW |
| airway, peak as during MV | PPEAK |
| airway, plateau as during MV | PPLAT |
| airway, positive end-expiratory | PEEP |
| alveolar (total) | PA |
| atmosphere (unit of pressure) | atm |
| barometric, ambient | PB |
| carbon dioxide | Pco2 |
| carbon dioxide, alveolar partial | PAco2 |
| carbon dioxide, arterial partial | Paco2 |
| carbon dioxide, end-expiratory partial | PÉco2 |
| carbon dioxide, expired | PEco2 |
| carbon dioxide, inspired | PIco2 |
| carbon dioxide, mean expiratory | PĒco2 |
| carbon dioxide, mixed venous blood | Pv̄co2 |
| colloid osmotic, of blood proteins | πMV |
| colloid osmotic, of interstitial proteins | πPMV |
| intrapleural | PIP |
| nitrogen | PN2 |
| oxygen | Po2 |
| oxygen, alveolar–arterial gradient or difference | (A – a)Po2 |
| oxygen, alveolar capillary | PCo2 |
| oxygen, alveolar end-capillary | PĆo2 |
| oxygen, alveolar partial | PAo2 |
| oxygen, arterial partial | Pao2 |
| oxygen, arterial saturation by oximetry | Sao2 (%) |
| oxygen, inspired | PIo2 |
| oxygen, mixed venous partial | Pv̄o2 |
| oxygen, mixed venous saturation by oximetry | Sv̄o2 (%) |
| oxygen, to half-oxygenate Hb | P50 |
| pulmonary arterial blood | PPA |
| pulmonary artery wedge (by PAC) | PPW |
| pulmonary capillary or microvascular | PMV |
| pulmonary peri-microvascular or interstitial | PPMV |
| pulmonary venous blood | PPV |
| systemic blood, diastolic | DP |
| systemic blood, mean | MAP |
| systemic blood, systolic | SP |
|
| Vital signs | |
| cardiac output | Q̇(L/min) |
| heart or pulse rate | HR(b/min) |
| predicted body weight, often "ideal" | PBW(kg) |
| respiratory frequency | f(breaths/min) (note italics) |
| temperature, ambient environmental in Celsius | TA(°C) |
| temperature, body or rectal in Celsius | TB(°C) |
| Volume (all types) and related measurements | |
| alveolar capillary blood | VC(mL) |
| alveolar gas | VA(mL or L) |
| dead space | VD(mL or L) |
| dead space/tidal, ratio | VD/VT (dimensionless) |
| expiratory reserve | ERV (mL or L) |
| forced expiratory in "x" seconds | FEVx, as in FEV1 (mL or L) |
| forced vital capacity | FVC (mL or L) |
| functional residual capacity | FRC (mL or L) |
| inspiratory reserve | IRV (mL or L) |
| length of a structure, as an airway | l(note italics) |
| minimal lung tissue, collapsed and airless | VMIN (mL or L) |
| radius of curvature, as an alveolus | r(note italics) |
| residual lung | RV(mL or L) |
| slow vital capacity | SVC(mL or L) |
| tidal | VT(mL or L) |
| total lung capacity | TLC(mL or L) |
| vital capacity of the lung | VC(mL or L) |