Srimad Bhagavatam Canto 04, Chapter 28, Text 15

SB 4.28.15

sithilavayavo yarhi
 gandharvair hrta-paurusah
yavanair aribhi rajann
 uparuddho ruroda ha
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
The limbs of the serpent’s body were slackened by the Gandharvas and Yavana soldiers, who had thoroughly defeated his bodily strength. When he attempted to leave the body, he was checked by his enemies. Being thus baffled in his attempt, he began to cry loudly.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:  
At the last stage of life, the different gates of the body are choked by the effects of disease, which are caused by an imbalance of bile, mucus and air. Thus the living entity cannot clearly express his difficulties, and surrounding relatives hear the sound “ghura ghura” from a dying man. In his Mukunda-mala-stotra, King Kulasekhara states:
krsna tvadiya-padapankaja-pañjarantam
 adyaiva me visatu manasa-raja-hamsah
prana-prayana-samaye kapha-vata-pittaih
 kanthavarodhana-vidhau smaranam kutas te
“My dear Krsna, please help me die immediately so that the swan of my mind may be encircled by the stem of Your lotus feet. Otherwise at the time of my final breath, when my throat is choked up, how will it be possible for me to think of You?” The swan takes great pleasure in diving within water and being encircled by the stem of the lotus flower. This entanglement is sporting joy. If, in our healthy condition, we think of the lotus feet of the Lord and die, it is most fortunate. In old age, at the time of death, the throat sometimes becomes choked with mucus or blocked by air. At such a time the sound vibration of Hare Krsna, the maha-mantra, may not come out. Thus one may forget Krsna. Of course, those who are strong in Krsna consciousness cannot possibly forget Krsna at any stage because they are accustomed to chanting the Hare Krsna mantra, especially when there is a signal from death.
Srimad Bhagavatam Canto 04, Chapter 28, Text 14
Srimad Bhagavatam Canto 04, Chapter 28, Text 16