Patient inputs
Date of birth
Touchdose uses the patient's birth date for formulary filtering operations and any required dose calculations.
In the event that Touchdose is integrated with an Electronic Health Record (EHR), the patient's date of birth will be retrieved from the EHR. The system will indicate an error if a valid birth date is not available.
However, when Touchdose is not integrated with an EHR, the clinician is required to manually input the patient's date of birth.
It's important to note that Touchdose exclusively supports patients up to 110 years of age and does not accept a birth date in the future.
Actual age, derived from the birth date, is employed for filtering the underlying formulary, and no provision is made for corrected gestational age. Touchdose is not configured to carry out any operations based on corrected gestational age or to indicate dosing criteria associated with corrected gestational age considerations. Clinicians must refer to supplementary resources if considerations related to corrected gestational age are applicable.
Not being aware of this Contraindication could potentially lead to harm to the patient.
Validation of patient inputs for paediatric patients, such as weight-for-age, is conducted using growth data applicable to children born at term.
Birth sex
Birth sex is a mandatory property and must be specified as either male or female.
In the case where Touchdose is integrated with an EHR, the birth sex will be retrieved. An error will occur if a valid birth sex is not available for the patient.
On the other hand, if Touchdose is not integrated with an EHR, the clinician is responsible for selecting the patient's birth sex.
Birth sex pertains to the patient's sex assigned at birth, which may not align with the patient's gender identity. For instance, a patient may have been assigned male at birth but identifies as female. Formulary recommendations and validation processes may be specific to the assigned birth sex. Hence, it is crucial to use birth sex instead of gender. Touchdose does not accommodate any indeterminate birth sexes — see Contraindications for the position on patients with disorders or differences of sex development (DSD) or intersex variations.
Body weight
Body weight is a compulsory input for patients under 18 years of age. For patients aged 18 and above, body weight is optional unless explicitly needed by the underlying formulary to determine a patient-specific dose when generating dose recommendations. Body weight serves as a dosing weight and is utilised for Formulary filtering (refer to Formulary filtering), unless corrections based on weight are necessary (refer to Dosing Weight).
When Touchdose is integrated with an Electronic Health Record (EHR), the patient's body weight will be retrieved if available and not considered as an out of date observation, with a valid unit. If the weight in the EHR is considered outdated or if the unit is invalid, Touchdose will not use the value. Refer to Out of date patient inputs and Incorrect unit for guidance on handling such situations.
In cases where Touchdose is not integrated with an EHR, the clinician must input the patient's weight for a child and has the option to do so for an adult.
Touchdose exclusively accepts body weight as a numeric value in kilograms. Acceptable ranges are as follows:
- Female adults: 39 kg to 200 kg
- Male adults: 45 kg to 200 kg
- Children: between the 0.01th and 99.99th percentiles based on growth charts that consider age and sex
When Touchdose requires body weight but the value is unknown, the user must input the patient's body weight in a pop-up with an input box. Depending on the site's configuration, there may be an option to update the EHR with the newly entered value (see Observation writeback). If not selected, the value will only be used by Touchdose until the application is closed.
Refer to the figure below for the pop-up when the system requires weight, along with the checkbox to update the EHR with the newly entered value:
- Touchdose does validate body weight and ensures that an old reading is not used by the system, but it remains the clinician's responsibility to ensure the value is as accurate and up-to-date as possible. A patient's weight can significantly change within the allowable time period of a reading. Failure by the clinician to ensure the patient's body weight is correct may result in error.
- As explained in Limitations and Contraindications, Touchdose does not differentiate dosing recommendations based on pregnancy status. Clinicians who, at their discretion, choose to use dosing suggestions provided by Touchdose in pregnant patients, despite the contraindications and warnings, should be aware that the dosing suggestions made by Touchdose will be based on whatever body weight is passed to the Device. Any free-text instructions present in the reference formulary data regarding the preference to use early pregnancy weights will not have been considered by the Device.
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Body weight, in conjunction with body height, is utilised to calculate and validate patient BMI and determine clinical obesity (refer to Obesity Status).
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Body weight is employed in the computation of body surface area.
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Touchdose adheres to guidance from the Royal College of Paediatrics and Child Health Growth Charts for data validation. The Royal College of Paediatrics and Child Health (RCPCH) recommends the use of different growth charts for distinct patient age groups:
- Children aged 2 weeks up to 4 years (excluding 4 years): World Health Organisation growth standard data
- Children aged 4 years up to 18 years (excluding 18 years): UK1990
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For children under 2 weeks, where there is no specific RCPCH guidance, Dosium has opted to use UK1990. This decision is based on the inclusion of data for these patients and its reference by the RCPCH for children of other ages.
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Touchdose does not incorporate special validation rules for children with alterations to expected growth, such as ex-premature children or children with Down syndrome. Any children with body weight values outside the permissible percentile ranges mentioned earlier will not pass Touchdose validation rules, leading to the inability to receive dosing recommendations in such cases.
For information about how to optionally enter a missing weight or edit an existing weight see the section below called Patient header.
Height or length
Body height is optional unless explicitly needed by the underlying formulary to determine a patient-specific dose when generating dose recommendations.
When Touchdose is integrated with an Electronic Health Record (EHR), the patient's body height will be extracted from the EHR if available and not considered an out of date observation, with a valid unit. If the height in the EHR is considered outdated or has an invalid unit, Touchdose will not use the value. Refer to Out of date patient inputs and Incorrect unit for guidance on handling.
In cases where Touchdose is not integrated with an EHR, the clinician has the option to input the patient's height when creating a patient.
Touchdose accepts body height as a numeric value in centimetres; for example, a patient 1.6m tall should have a body height of 160cm.
Allowable values are within the following ranges:
- Adults: 40cm to 240cm
- Children: between the 0.01th and the 99.99th percentiles based on growth charts that consider age and sex
Height will only be required when the system needs to calculate BSA for an adult or to determine the patient's obesity status. See Body surface area and Obesity status for more information on how the system will request height to be input. Depending on the site's configuration, there may be an option to update the EHR with the newly entered value (see Observation writeback). If the “Update EHR” check box is not selected, the value will only be used by Touchdose until the application is closed.
Touchdose validates body height and ensures that an outdated reading is not used by the system. However, it remains the clinician's responsibility to guarantee that the value is as accurate and up-to-date as possible. Failure by the clinician to ensure the patient's body height is correct may lead to errors in the system.
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Touchdose does not differentiate between height measured standing, applicable to patients able to stand, and supine length, taken in children or patients unable to stand.
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Body height, in conjunction with body weight, is employed to calculate and validate patient body-mass-index as well as to determine clinical Obesity status.
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Both body height and body weight are used to calculate body surface area in adults and in children weighing over 90kg.
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Touchdose adheres to guidance from the Royal College of Paediatrics and Child Health Growth Charts for data validation. The Royal College of Paediatrics and Child Health (RCPCH) recommends the use of different growth charts for distinct patient age groups as follows:
- Children aged 2 weeks up to 4 years (excluding 4 years): World Health Organisation growth standard data
- Children aged 4 years up to 18 years (excluding 18 years): UK1990
- For children under 2 weeks, where there is no specific RCPCH guidance, Dosium has chosen to use UK1990. This decision is based on the inclusion of data for these patients and its reference by the RCPCH for children of other ages.
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Touchdose does not incorporate special validation rules for children with alterations to expected growth, such as ex-premature children or children with Down syndrome. Any child with body height values outside of the permissible percentile ranges mentioned earlier will not pass the Touchdose validation rules, resulting in the inability to receive dosing recommendations in such cases.
For information about how to optionally enter a missing height or edit an existing height see the section below called Patient header.
Body surface area
BSA is optional unless specifically mandated by the underlying formulary for determining a patient-specific dose when generating dose recommendations. Touchdose computes BSA using other patient parameters. BSA cannot be directly entered or retrieved from an Electronic Health Record (EHR).
Touchdose calculates BSA when the necessary patient properties are available. See Calculated body surface area for more information. The BSA calculation process is as follows:
- Children 90kg and under: Touchdose can always calculate BSA for children, as the calculation relies only on mandatory properties for a child. BSA is determined using the Sharkey method.
- Adults and children over 90kg: The patient's body weight and height are required, in addition to the mandatory properties. BSA is calculated using the Dubois Dubois method.
BSA is calculated in square metres (m2), and the value is required to fall between 0.1m2 and 3m2.
When BSA is needed by Touchdose but is unknown, the clinician must enter weight and/or height, depending on which observations are missing. The value calculated and used by Touchdose will not automatically update in the patients EHR. If you would like to update the patients BSA in the EHR you need to do so outside of Touchdose in the normal way that you would enter the patient’s BSA.
Refer to the figure below for the pop-up when the system requires BSA:
The “Update EHR” check box allows you to choose whether you want the newly entered value for height to be saved to your EHR (see Observation writeback). This functionality will not always be available and depends on your site's configuration.
- Touchdose validates BSA and ensures that the parameters that are used to calculate BSA are not outdated, but it remains the clinician's responsibility to guarantee the accuracy and currency of the value. Failure by the clinician to ensure the patient's BSA is correct may result in errors.
- If the clinician deems the calculated BSA unsuitable they must use another method to determine the dose.
Creatinine
When Touchdose is integrated with an Electronic Health Record (EHR), the patient’s creatinine will be retrieved from the EHR for children.
Creatinine is an optional parameter that is retrieved and displayed for informational purposes only. If a valid and in-date creatinine value is available, it will be used to calculate eGFR when a height is present - see eGFR for more details.
Touchdose does not use creatinine as an input for dosing recommendations. It is your responsibility to consider the implications of any displayed creatinine values. Creatinine is shown in the Patient header with a note indicating that it is for informational purposes only.
Touchdose accepts creatinine as a numeric value in µmol/L.
Allowable range: 10–1000 µmol/L.
If an incorrect unit is detected, the creatinine value will not be used, and an indication will be provided that retrieval failed due to an incorrect unit. If the creatinine value is outdated, it will still be retrieved but will be marked as out of date. See Out of date patient inputs and Incorrect unit for guidance on handling such cases.
It is crucial to understand that Touchdose does not factor creatinine into dosing recommendations. Failing to account for this and not exercising appropriate caution when adjusting doses or medications may lead to patient harm.
Touchdose validates creatinine and ensures that an outdated reading is not used by the system. However, it remains the clinician's responsibility to guarantee that the value is as accurate and up-to-date as possible. Failure by the clinician to ensure the patient's creatinine is correct may lead to errors in the system.
Preterms and expreterms
Touchdose functions according to the actual age of a child, determined by their date of birth. Consequently, Touchdose is not configured to execute any operations based on corrected gestational age, nor does it provide information on dosing criteria considering corrected gestational age. Clinical end users are advised to refer to additional resources if corrected gestational age considerations are relevant.
Validation of patient inputs for paediatric patients is conducted using growth data applicable to children born at term.
Out of date patient inputs from the EP System
Note that this section is only applicable when Touchdose is integrated with an Electronic Health Record (EHR), and observations are retrieved from the EHR.
Touchdose does not accept out-of-date observations for body weight, body height or creatinine. If an observation in the EHR is deemed to be out of date, the value will not be used by Touchdose. The input will be marked as missing in the patient header, but there will be an information icon to notify the user that the value is missing because it is considered out of date. If the user clicks to enter the missing value, the previous observation will be displayed, along with information about how long ago the observation was entered into the system. Refer to the figure below to see how it will appear when an observation is considered out of date:
Weight and height out of date classification
Touchdose deems a parameter to be out of date based on the age of the patient and how long ago the value was entered into the EHR. The table below outlines what Touchdose accepts as a recent enough reading:
| Patient age | Allowable age of reading |
|---|---|
| Up to but not including 3 months | 7 days or less |
| 3 months up to but not including 12 years | Less than 31 days |
| 12 years up to but not including 18 years | Less than 6 months |
| 18 years and above | Less than a year |
Creatinine out of date classification
Creatinine is classified as out of date if it is older than 1 week old.
If there is no valid observation date in the EHR associated to the observation then the value will not be retrieved.
Incorrect unit
Note that this section is only applicable when Touchdose is integrated with an Electronic Health Record (EHR), and observations are retrieved from the EHR.
The only units that Touchdose accepts are as follows:
- Body weight: kg
- Body height: cm
- Creatinine: umol/L
If any other unit is used, the observation will not be utilised by Touchdose. The input will be marked as missing in the patient header, but there will be an information icon to notify the user that the value is missing due to an invalid unit. Refer to the figure below to see how it will appear when an observation is not used because of an incorrect unit:
Observation writeback
Where the integration with the EP System supports it, observations entered manually by the clinician within Touchdose — such as weight or height — can be written back to the patient's record in the EHR. This is referred to as observation writeback. Where this option is available, an "Update EHR" checkbox is presented alongside the input field; selecting the checkbox writes the new value to the EHR. If the checkbox is not selected, the value is used by Touchdose only for the current session.
Observation writeback is distinct from order writeback, which transfers the resulting dose recommendation into the EP System's pre-signature order form. The two have separate availability conditions; either, both, or neither may be supported by a given integration.
Summary of allowable parameter ranges
| Parameter | Adult | Child |
|---|---|---|
| Height | Max: 2.4m Min: 0.4m | Max: 99.99th percentile for age and sex Min: 0.01th percentile for age and sex |
| Weight | Max: 200kg Min (Female): 39kg Min (Male): 45kg | Max: 99.99th percentile for age and sex Min: 0.01th percentile for age and sex |
| Age | Max: 110 years | Min: Current date |
| BSA | Adult and child over 90kg Max: 3m2 Min: 0.1m2 | Child 90kg and under Min: 0.1m2 |
| BMI | Max: 50kg/m2 Min: 12kg/m2 | Max: 99.99th percentile for age and sex Min: 0.01th percentile for age and sex |
| Creatinine | Not retrieved for adults | Max: 1000umol/L Min: 10 umol/L |
Please see each of the respective parameter sections for more information.