Effects of pharyngeal cooling on brain temperature in primates and humans: A study for proof of principle

Yoshimasa Takeda, Hiroshi Hashimoto, Koji Fumoto, Tetsuya Danura, Hiromichi Naito, Naoki Morimoto, Hiroshi Katayama, Soichiro Fushimi, Akihiro Matsukawa, Aiji Ohtsuka, Kiyoshi Morita

Research output: Contribution to journalArticlepeer-review

17 Citations (Scopus)


Background: Pharyngeal cooling decreases brain temperature by cooling carotid arteries. This study was designed to evaluate the principle of pharyngeal cooling in monkeys and humans. Methods: Monkeys (n = 10) were resuscitated following 12 min of cardiac arrest. Pharyngeal cooling (n = 5), in which cold saline (5°C) was perfused into the cuff at the rate of 500 ml/min, was initiated simultaneously with the onset of resuscitation for 30 min. Patients (n = 3) who were in an intensive care unit were subjected to 30 min of pharyngeal cooling under propofol anesthesia. Results: In the animal study, core brain temperature was significantly decreased compared with that in the control group by 1.9°C (SD = 0.8, P < 0.001) and 3.1°C (SD = 1.0, P < 0.001) at 10 min and 30 min after the onset of cooling, respectively. The cooling effect was more evident in an animal with low postresuscitation blood pressure. Total dose of epinephrine, number of direct current shocks, and recovery of blood pressure were not different between the two groups. The pharyngeal epithelium was microscopically intact on day 5. In the clinical study, insertion of the cuff and start of perfusion did not affect heart rate or blood pressure. Tympanic temperature was decreased by 0.6 ± 0.1°C/30 min without affecting bladder temperature. The pharynx was macroscopically intact for 3 days. Conclusions: Pharyngeal cooling rapidly and selectively decreased brain temperature in primates and tympanic temperature in humans and did not have adverse effects on return of spontaneous circulation, even when initiated during cardiac arrest in primates.

Original languageEnglish
Pages (from-to)117-125
Number of pages9
Issue number1
Publication statusPublished - Jul 2012

ASJC Scopus subject areas

  • Anesthesiology and Pain Medicine


Dive into the research topics of 'Effects of pharyngeal cooling on brain temperature in primates and humans: A study for proof of principle'. Together they form a unique fingerprint.

Cite this