query

 @foreach($tt->pto2 as $rt)
                            @if($rt->spo_2 >80)
                            
                              <td>{{$rt->spo_2 }}</td>
                              @endif
                              @endforeach 
´´´´
this is working but i need the value between them 

If these are your Model and relation names (I made these up), then this should work:

Patient::whereHas('vitals', function ($query) { $query->where('body_temp', '>=', 45); })->get();

https://laravel.com/docs/master/eloquent-relationships#querying-relations

                       ´´´´
                        @foreach($tt->pto2 as $rt)
                        @if($rt->spo_2 >80 && $rt->spo_2 <6000)
                        
                          <td>{{$rt->spo_2 }}</td>
                          @endif
                          @endforeach
                         ````

Thank you for your great support I got the answer by another method hope helpful for other

Thank you Burlresearch Your idea is grate to implement in the Restful API