consumer protection act problem

Can anyone help me with this problem and cite a relevent case? I could not understand the last part of the problem and also did not get any relevent cases in this regard. The problem is

Mr.Pradeep appellant started vomiting and having loose motions frequently. After some laboratory tests, the respondent Doctor Mr.Ashok Kumar put him on medication and also injected glucose saline to his right shoulder. This did not improve condition of appellant who started omitting and having loose motions frequently  on 02-10-1996 the Doctor Mr.Ashok Kumar being respondent administered glucose saline through the left foot of the appellant. In the evening the parents of appellant noticed swelling in the toe of his left foot which was turning black. This was brought to notice of respondent that blackish discolouration has spread. There upon appellant was sent to one Dr.Mehata who was known to the respondent. Dr.Mehata applied a small cut removed black colored fluid from the left toe of the appellant and gave some medicine.

            In the morning of 4-10-1996 it was noticed that left leg of appellant has become totally blacken to the knee. There upon he was taken to Hyderabad Dr.Aakash, who examined appellant at Hyderabad suspected that he had developed gangrene in his left leg and advised his admission in Yashoda Hospital, Hyderabad.

            The appellant was operated in that Hospital and his left leg was imputed below the knee.

            The appellant filed a complaint through his father and claimed compensation of RS.12 lakhs by alleging negligence on part of respondent. According to appellant even though the factum of swelling of the toe and blackening of leg was brought to notice of respondent, he did not bother to get the applicant examining through an export which could save his leg.

            It was also pleaded that due to respondents’ failure to pay requesite attention, the appellants left leg had to be amputed below knee and he will have to suffer through out his life.

            The respondent also pleaded his version of statements and denied allegations of negligence and pleaded that he had taken every possible care in treating the appellant.

            The state commission concluding that the respondent has not exercised the reasonable care while treating appellant and awarding compensation of RS.6 Lakhs with interest of 9%.

            Appeal was filed against by the respondent which was allowed by National Commission on solidarity ground, that in his cross examination, Dr.Mehata admitted that there would be 10 to 12 other reasons for development of gangrene.  Appeal held National Commission has duty bound to pay serious attention on the respondent failure to produce case sheet/ bed ticket pertaining to treatment given to appellant was held from state commission till complainants’ evidence was virtually over.