Siman 370ש״ע
1 א

מי הוא החשוב כמת אף על פי שעודנו חי. ובו סעיף אחד:
מי שנשברה מפרקתו ורוב בשר עמה וכן מי שנקרע מגבו כדג אפילו עדיין הוא חי חשוב כמת ומטמא אבל גוסס ומי שנשחטו בו ב' סימנים או פצוע פצעים הרבה אינם מטמאין עד שתצא נפשם ומ"מ אסור ליכנס לבית שיש בו גוסס (ויש מתירין) (ר"ן סוף מ"ק ומרדכי פרק אלו מגלחין בשם בה"ג) (וטוב להחמיר):

One whose neckbone and the larger portion of the surrounding flesh was broken,1Ḥul. 21a in accord with Rab Judah on the authority of Samuel. and likewise, one who was torn up along the back2But not if one was ripped up along the front — ShaK. as a fish, even if he is still living, is regarded as dead and defiles [through overshadowing].3Ḥul. ibid. in accord with R. Joḥanan and Samuel. In the case of an old man whose neckbone alone was broken without the larger portion of the surrounding flesh having been severed, he is considered dead and defiles (ibid.). If one’s neck was split widthwise into two or if the spinal column was cut towards its interior, or if split in two, he defiles by overshadowing — ShaK. Hence, a Kohen is prohibited to enter the same house or tent wherein these persons are present. But a dying person4 supra § 339. and one in whom both organs5The windpipe and the oesophagus. were cut, or one who is wounded [with] many [open] wounds, do not defile [men or vessels] until their soul departs.6Derived from Git. 70b. Nevertheless, it is forbidden [for a Kohen]7 Glos. to enter a house in which there is a dying person,8Naz. 43a. Tosaf. ibid. s.v. ומהכא. The prohibition mentioned in connection with Kohanim (Priests) who are cautioned against defiling themselves for the dead who are not near-of-kin states: ‘To profane himself’ (Lev. XXI, 4), which is explained (ibid. according to one opinion) to mean that the actual profanation is forbidden until the time that the dying person is dead, although no defilement exists as yet, the reason being that the majority of dying persons, die. According to another opinion, since the Bible in speaking of the Nazirite’s prohibition against uncleanness even for near-of-kin, states: ‘When they die’ (Num. VI, 7), it follows that he may be present with them until they actually die. Hence, there is no profanation prior to death. Caro’s ruling here follows the first opinion. and some permit,9RaN to M.K. III end and Mord. ibid. on the authority of BeHaGG. and it is proper to adopt the stricter view.10One is not required to arouse a Kohen from sleep in order to inform him that a dying person is present in the same house so that the Kohen should leave (this would be required in case a corpse were present there. infra § 372 Gloss). If they did inform him and he was undressed, he may take time to dress himself and then leave — ShaK. A physician who is a Kohen may enter the house of a dying person in order to heal the latter even if there is another physician available who is not a KohenP.Tesh.