Reversal of apnoea by aspiration reflex in anaesthetized cats

Tomori, Z; Benacka, R; Donič, Viliam; Tkáčová, Ružena

doi:10.1183/09031936.93.04091117

Cited by 15 publications

(3 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Both processes possess strong resuscitation efficacy frequently resu lting in recovery from hypoxic or asphyxic apnoea due to rapid aeration of the lungs and strong intero-and proprioceptive inputs [2,9,16].…”

Section: Discussionmentioning

confidence: 99%

“…The reflex can also be made to interrupt various kinds of apnoea in anaesthetized cats [12,13,21] causing a violent arousal which may contribute to a higher recovery rate from hypoxic apnoea by the aspiration reflex than by gasping [9]. Hence, investigation of the arousal effect of the airway stimulation could contribute to the explanation of some questions in the pathogenesis of sudden infant death syndrome.…”

Section: Discussionmentioning

confidence: 99%

“…During previous experiments in adult cats anaesthetized with sodium pentobarbitone, autoresuscitation by gasping was effective in approximately only ,20% of apnoeic episodes induced by inhalation of pure nitrogen. Hypoxic apnoea could be reversed more often by repeated evocation of the snifflike aspiration reflex [9). This reflex can be induced by mechanical stimulation of the nasopharyngeal mucosa and comprises an extremely strong and fast inspiratory effort [10][11][12][13] resembling a gasp, and also a sniff which is a semi-reflex response that occurs in animals when a new odour attracts attention [14].…”

mentioning

confidence: 99%

See 2 more Smart Citations

Comparison of inspiratory effort in sniff-like aspiration reflex, gasping and normal breathing in cats

Tomori¹,

Donič²,

Kurpas³

1993

Eur Respir J

View full text Add to dashboard Cite

The changes in airway occlusion pressure and airflow, occurring during two spasmodic breathing patterns, were studied and compared with normal breathing pattern in 12 anaesthetized cats. The inspiratory effort developed during the sniff-like aspiration reflex elicited by mechanical stimulation of the nasopharynx under control conditions proved to be very similar in character and intensity to the activity observed during gasping which occurred on resuscitation, of the same cats, from hypoxic apnoea. The starting (P50) and maximum (Pmax) airway occlusion pressure developed in these two spasmodic breathing patterns were very high. Extremely rapid rates of contraction and relaxation were detected by computer-assisted measurements of dynamic changes in both the pressure values and the slopes of pressure curves. The results suggest common effector mechanisms, reflecting similar forceful inspiratory drives, for the aspiration reflex and gasping. These two spasmodic processes differ substantially from normal breathing. Nevertheless, the aspiration reflex differs from gasping in that it can be elicited by activation of upper airway afferents during eupnea. Moreover, as yet, there is no definitive evidence that the brainstem mechanisms responsible for generating the aspiration reflex are the same as those of the gasp. The main benefits of this reflex are its rather easy elicitability under various conditions and its capability to induce important cardiorespiratory effects (e.g.) reversal of central apnoea) owing to its powerful activity.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Comparison of inspiratory effort in sniff-like aspiration reflex, gasping and normal breathing in cats

Tomori¹,

Donič²,

Kurpas³

1993

Eur Respir J

View full text Add to dashboard Cite

show abstract

Characterization of successful and failed autoresuscitation in human infants, including those dying of SIDS

Sridhar

Thach

Kelly

et al. 2003

Pediatric Pulmonology

136

106

View full text Add to dashboard Cite

Our purpose was to identify and further characterize physiologic mechanisms relevant to autoresuscitation from hypoxic apnea in infants dying suddenly and unexpectedly. We studied cardiorespiratory recordings of 24 infants (age range, 0.8-21 months) who died suddenly while being monitored at home. These recordings were analyzed for features indicated by studies in animal models to be characteristic of hypoxic gasping, and of recovery from bradycardia and apnea associated with gasping (e.g., autoresuscitation). Findings in 5 infants diagnosed as having sudden infant death syndrome were compared with 6 non-SIDS infants whose deaths resulted from other conditions. Additionally, we studied 15 healthy infants during sleep, using home monitor and other respiratory recording techniques, in order to obtain comparison data. We found in recordings from 23 of 24 subjects that hypoxic gasps with characteristic features occurred immediately preceding death. A unique pattern of complex, closely spaced gasps ("double" or "triple" gasps) was present in many subjects. Evidence of partially successful autoresuscitation closely following one or more gasps occurred in 11 subjects, while another 4 had evidence of complete autoresuscitation with return of normal heart rate and resolution of apnea on one or more occasions. Significant differences between SIDS infants and those dying from other causes included increased occurrence of complex gasps and decreased occurrence of partial or complete autoresuscitation in the SIDS infants. The non-SIDS cases were different from the SIDS cases in that only one had "double" gasps (n = 7), while none had "triple" gasps, as compared with 4 out of 5 SIDS cases with these patterns (P < 0.05, chi-square). Also, in contrast with the SIDS cases, more of the cases with specific postmortem diagnoses had evidence of partial (5 out of 6 cases) or complete (1 out of 6 cases) autoresuscitation (P < 0.05, chi-square). We conclude that partial or complete autoresuscitation by gasping is not uncommon in moribund infants during the first year of life. Failure of autoresuscitation mechanisms other than failure to initiate gasping may be characteristic of infants dying of SIDS. Some SIDS infants appear to be different from infants dying with other diagnoses with respect to efficacy and characteristics of hypoxic gasping.

show abstract