Is the word deitado the same in Brazilian and European Portuguese?

Yes

The word "deitado" is identical in meaning, spelling, and grammatical category in both Brazilian and Continental Portuguese. The primary difference lies in pronunciation. In Brazil, vowels are generally more open and clearly articulated. In Portugal, unstressed vowels (such as the "e" in deitado) are often reduced or "swallowed," making the word sound much more clipped and shorter.

While the word itself does not change, the grammatical construction surrounding it typically differs. Brazilians frequently use the gerund (descansando) to describe an ongoing action while being "deitado," whereas Portuguese speakers typically use the preposition a followed by the infinitive (a descansar).

Brazilian Portuguese Examples

1. Eu estou deitado no sofá descansando. (I am lying on the sofa resting.)
2. O bebê ficou deitado o dia todo. (The baby stayed lying down all day.)
3. Não consigo ficar deitado com essa dor de cabeça. (I can't stay lying down with this headache.)
4. Ele estava deitado de lado. (He was lying on his side.)
5. Fique deitado até eu te chamar. (Stay lying down until I call you.)

Portuguese (Portugal) Examples

1. Estou deitado no sofá a descansar. (I am lying on the sofa resting.)
2. O bebé ficou deitado o dia inteiro. (The baby stayed lying down the whole day.)
3. Não consigo ficar deitado com esta dor de cabeça. (I can't stay lying down with this headache.)
4. Ele estava deitado de lado. (He was lying on his side.)
5. Fica deitado até eu chamar-te. (Stay lying down until I call you.)