Mdcalc Peak Flow

Mdcalc Peak Flow

How does this Geneva score for pulmonary embolism calculator work?

  • Flow, to floor min flow, to off (remove cannula). Avoid gradual weans using other flows. Weaning from max flow directly to off is also possible, as patient condition allows. Team guidance: physicians should order flow rate after assessing patient, observe patient fori 10 minutes after flow.
  • Description The Predicted Peak Flow calculator determines expected peak flow to help quantify asthma exacerbation severity.

This is a health score designed to risk assess the probability of pulmonary embolism based on the three versions of the PE score, each in a different tab so you can use any of them or compare them as preferred. This Geneva score for pulmonary embolism calculator is based on risk factors and clinical determinations and is considered to be one of the most accurate available.

Peak Expiratory Flow Conditions It May Diagnose

Peak

1. The revised Geneva score has been introduced more recently and uses 8 parameters as it does not include the arterial blood gas sample found in the original model. The revised version of the Geneva score is considered to be as effective as other PE risk models such as the Wells score.

CriteriaScoreInfo
Age >651Age increases the risk of PE
Previous DVT or PE3Previous deep venous thrombosis is a risk factor
Surgery or fracture in the last 4 weeks2Due to risk of vessel damage and prolonged immobilization in recovery
Active malignant condition2It has been demonstrated that in cancer patient the risk is higher
Unilateral lower limb pain3Pain or swelling are suggestive of blood stagnation or DVT
Pain on palpation of lower limb and unilateral edema4Pain or swelling are suggestive of blood stagnation or DVT
Hemoptysis3expectoration of blood or blood-tinged sputum
Heart rate 75-94 bpm3Increased heart rate as a symptom
Heart rate >94 bpm5Rapid heart rate as sign of pulmonary embolism

2. The original Geneva score comprises of 7 risk factors and other clinical parameters and is set to give a higher relevance to age groups and the partial pressures of O2 and CO2 in arterial blood.

Flow

FOR PHYSICIANS: The ACT is: Reference: 1. Nathan RA et al. J Allergy Clin Immunol. If your score is 19 or less, your asthma may not be controlled as well as it could be. Peak expiratory flow rate (PEFR) is estimated via one of these equations: Children PEFR = ((Height in cm - 100) x 5) + 100 Adult Men = (((Height in m x 5.48) + 1.58) - (Age x 0.041)) x 60 Adult Women = (((Height in m x 3.72) + 2.24) - (Age x 0.03)) x 60.

CriteriaScoreInfo
Age 60 - 791Age is a risk factor in PE
Age >802The greater the age is the higher the risk
Previous DVT or PE2A history of deep venous thrombosis or another PE increases risk
Recent surgery in past 4 weeks3Recent surgery suggests immobilization or risk of vessel damage
Heart rate >100 bpm1Rapid heart rate as sign of PE
PaCO2 <35 mmHg2Decreased pressure shows that the embolized areas are not functioning properly
PaCO2 35 - 39 mmHg1Sign of hyperventilation
PaO2 <49 mmHg4Indicative of pulmonary obstruction
PaO2 49 - 59 mmHg3Sign of hypoventilation
PaO2 60 - 71 mmHg2Used as part of the pressure ratio in PE risk assessment
PaO2 72 - 82 mmHg1Low decrease in partial oxygen pressure
X ray - band atelectasis1Atelectasis due to loss of blood flow and lack of CO2
X ray - hemidiaphragm elevation1Highly suggestive imagistic of acute PE

3. The simplified Geneva score is the latest version dating from 2008. It is based more on the revised version as it keeps its criteria but changes each element’s weight to just 1 score point in an attempt to make the model easier to remember and less prone to inaccuracies. The only factor that is awarded 2 points is the heart rate >94 bpm.

Clinical probability in the Geneva models for PE

The clinical assessment of a suspected acute pulmonary embolism is very important in this common hospital admission cause. The result of the scoring models categorizes patients in low, intermediate or high risk groups. These are the Geneva PE probability scores and their interpretation:

Geneva modelTotal scorePE probability
Original0 - 5Low
5 - 8Intermediate
>8High
Revised0 - 3Low 8%
4 - 10Intermediate 28%
>11High 74%
Simplified0 - 2Unlikely
>2Probable

Causes of pulmonary embolism

This is a very serious condition that occurs when the pulmonary artery that carries blood to the lungs becomes blocked, usually by a blood clot. In most cases it is a clot formed in one of the deep beins in the legs, phenomenon called DVT (deep vain thrombosis). The main factors that contribute to the risk of blood clot development are inactivity, blood vessel damage and blood that clots easily.

Inactivity – because the blood slows down and facilitates the formation of clots: e.g. after a debilitating illness, operation or after a very long journey by train, car etc.

Blood vessel damage – e.g. narrowing or blockage that prevents direct normal blood flow and favors the formation of clots and also the inflammation of the blood vessels (vasculitis).

Conditions where blood clots easily – e.g. heart failure, thrombophilia, Hughes syndrome, chemotherapy. Amongst other factors there is age over 60, previous blood clots, obesity, family history, pregnancy, smoking.

Other PE scoring systems

Beside the three Geneva models there is also the Wells score with two versions, one original and one simplified, a Charlotte rule and the PISA model. All these use clinical determinations and other patient risk factors to assess the clinical probability of PE.

The Wells model takes account of the following factors:

- DVT evidence (swelling)

- Heart rate >100bpm

- Previous DVT or PE

Mdcalc Peak Flow

Predictive Peak Flow

- Immobilization in the past month

- Hemoptysis

- Malignancy

- PE as a highly likely diagnosis

The Charlotte rule uses the following criteria:

- Age > 50

- Heart rate > systolic blood pressure

- Surgery in past month

- Unilateral leg swelling

Peak Flow Measurement Prediction

- Hemoptysis

Mdcalc Peak Flow

- Unexplained pulse oximetry <95%

The Pisa model includes 10 variables positively associated with pulmonary embolism (age, gender, immobilization, DVT history, dyspnea, chest pain, syncope, hemoptysis, unilateral leg swelling, ECG determination) and six negatively associated with PE (cardiovascular disease or pulmonary disease history, orthopnea, fever, wheezes and crackles).

References

1) Klok FA, Mos IC, Nijkeuter M et al. (Oct. 2008). Simplification of the revised Geneva score for assessing clinical probability of pulmonary embolism. Archives of Internal Medicine 168 (19): 2131–6.

2) Le Gal G, Righini M, Roy PM et al. (Feb. 2006). Prediction of pulmonary embolism in the emergency department: the revised Geneva score. Annals of Internal Medicine 144 (3): 165–71.

Mdcalc Peak Flow Predicted

26 Jun, 2015