You're overwriting the hash value with each new patient. Try: 

$practice = {}; 

foreach $patient(@{$self->{patient_details}})
{
     push @{ $practice->{ $patient->{suregery_id} } }, $patient;
}

[download]

It creates an array of patients for each id.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
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In the absence of evidence, opinion is indistinguishable from prejudice.
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In reply to Re: In a hash with hashes by BrowserUk
in thread In a hash with hashes by weezer_316

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