ISO 10993-7:2008/ Amd.1:2019 - Classification of special populations

[akyt]

Hi everyone! Can you help me?

I have some doubts related to the implementation of Amendment 1 of the ISO 10993-7:2008 standard.

The amendment talks about new EO and ECH residual limits for products for special populations, such as premature neonates, neonates and children.
For example: for products with limited exposure (less than 24 hours), the limit for EO is 0.3 mg/Kg/day, and the limit for ECH is 0.64 mg/Kg/day.

We have in our portfolio medical devices classified as neonates, pediatric and infants.
So, how can I define a median body mass to establish the new limits of EO and ECH?
The amendment also establishes that the body mass used for each category of special patient population shall be justified and documented.

Another doubt: this amendment was published on 2019-12. What is the maximum period to adapt the company after this publication?

Thank you all.

 

[planB]

akyt,

2 options for body-mass references for your patient population:

• ISO 10993-17:2002, section 6.2.2, Devices specifically intended for use in neonates and children - quote:

TE calculations should be performed using body mass 3,5 kg for neonates and 10 kg for children as the human body mass for that device.

• Statistical data, either from national institutions or from the WHO

Unless there is a published transition period (which is not for this amendment), there is no fixed time frame, until when regulators expect compliance. Typically, this may be 1/2 - 1 year after publication. For this amendment, at least in the EU, the contents of this amendment have practically already been expected by notified bodies since 2016, after the French authorities raised serious concerns about this standard in 2014.

HTH,

Gerhard

 

[TMMullin3]

I'm having difficulty parsing what text replaces what with this amendment.
Just focusing on section 4.3.2 for example.
The amendment reads,"4.3.2, last paragraph Replace the paragraph with the following: When the device is intended to be used in special populations, the appropriate patient body mass shall be used for the derivation of the allowable limits. For example, if the device is intended to be used in premature neonates, neonates or children, the allowable limits shall be derived using the TI value of 0,02 mg/kg/day for EO and 0,029 mg/kg/day for ECH as established in G.6.4 and H.4.1.3, respectively. The appropriate default body mass used for each category of special patient population shall be justified and documented."

Does that replace the entire section on ECH limits including the bulleted 24h and 30d limits? If so, it seems to replace what was a fairly parallel structure between EO and ECH limits with something very much not parallel. It seems to replace those limits for ECH with the 0.029mg/kg/day limit, and yet not do the same for EO.

What actually is the last paragraph? What am I missing here? Is there someplace I can just get the amended standard?

Thanks in advance,
TMM

 

[planB]

TMM,

Consolidated section 4.3.2 would read like this (amendments in red):

4.3.2 Permanent contact devices

In the case of a device used in an adult of body mass mb = 70 kg, and with CEF = 0,2 and PEF = 1,0 (default factors),

the average daily dose of EO to patient shall not exceed 0,1 mg/d. In addition, the maximum EO dose shall not exceed:
⎯ 4 mg in the first 24 h;
⎯ 60 mg in the first 30 d;
⎯ 2.5 g in a lifetime.

the average daily dose of ECH to patient shall not exceed 0.4 mg/d. In addition, the maximum ECH dose shall not exceed:
⎯ 9 mg in the first 24 h;
⎯ 60 mg in the first 30 d;
⎯ 10 g in a lifetime.

When the device is intended to be used in special populations, the appropriate patient body mass shall be used for the derivation of the allowable limits. For example, if the device is intended to be used in premature neonates, neonates or children, the allowable limits shall be derived using the TI value of 0,02 mg/kg/day for EO and 0,029 mg/kg/day for ECH as established in G.6.4 and H.4.1.3, respectively. The appropriate default body mass used for each category of special patient population shall be justified and documented.

To my knowledge, there is unfortunately no consolidated edition of ISO 10993-7 including this latest amendment.

HTH,

 

[rmyjq]

TMM,

Consolidated section 4.3.2 would read like this (amendments in red):



To my knowledge, there is unfortunately no consolidated edition of ISO 10993-7 including this latest amendment.

HTH,

Exactly, same question as you, also in section 4.3.3.

 

[rmyjq]

According to this question, attach the calculation results, if any one has any comment?

 

[planB]

From a first glance, the attached Excel file seems to be a nice summary of the ISO 10993-7 annexes, detailing the residuals calculations. Any specifics you want to have addressed or discussed?

 

[rmyjq]

The residue accept limit of children, newborn, premature can not be simply calculate by body weight difference. For example, if calculated just from body weight, the first 30 days residue limit for children is: 60 mg/device (adult) / 70 kg (adult) x 10 kg (children) = 8.57 mg/device (children), which is difference from the following calculation results according to new revised standard.

 

[rmyjq]

Revised, V2, Add CEF and PEF calculation according to ISO 10993.17.

 

[Agnes Konings]

What about the special categories, mentioned in the ISO 10993-7:2008 norm. Are the limits of the special categories also affected by amendment 1 ? Meaning that recalculation of the limits of the special categories has be done for the weight of infants/neonates ?