On Respiration in the Dragonet Callionymus Lyra L

1968 ◽  
Vol 49 (3) ◽  
pp. 565-582
Author(s):  
G. M. HUGHES ◽  
SHUN-ICHI UMEZAWA
Keyword(s):  
Heart Rate ◽  
Oxygen Consumption ◽  
Time Course ◽  
Water Pressure ◽  
Minute Volume ◽  
Individual Variations ◽  
Wide Range ◽  
The Relationship ◽  
Respiratory Rhythms ◽  
Normal Ventilation

1. The usefulness of a bottom-living fish, the dragonet (Callionymus lyra), in experiments on fish respiration is described. The position and nature of its opercular opening made it possible to determine directly the volume of water pumped over the gills and the PO2 of the mixed expired water. The normal ventilation volume for a 100 g. fish was about 30 c.c./min. 2. The relationship between cardiac and respiratory rhythms was investigated and showed a variety of ratios. The heart usually beats more than once during each respiratory cycle. Individual variations in the coupling between these rhythms was common and close couplings were observed in the absence of anaesthetic and at normal PO2s. 3. Changes in minute volume produced by altering the hydrostatic pressure across the respiratory system did not affect the heart rate. Percentage utilization fell at higher flow rates. Changes in flow per cm. of water pressure gradient was less with negative gradients than when the static pressure on the mouth side exceeded that in the opercular collecting chamber. 4. Oxygen consumption of the fish is directly related to the ambient PO2 over a wide range (30-120 mm. Hg). Sudden lowering of the PO2 in the inspired water leads to compensatory responses in which the minute volume is maintained or increased as a result of a rise in stroke volume and lowered respiratory frequency: there is also a marked bradycardia. During recovery the increased oxygen consumption of the fish resulted from a rise in utilization rather than a change in the respiratory rate or ventilation volume. 5. Analysis of the time course of the changes in heart rate and ventilation volume in experiments in which PO2 was changed supports the view that the receptors mediating bradycardia occur on the gills and respond directly to the change in PO2 rather than to the secondary increase in flow produced by the hypoxia.

Energy expenditure by elite midget male ice hockey players in small-sided games

2017 ◽  
Vol 12 (4) ◽  
pp. 504-513 ◽  
Author(s):  
Charles-Mathieu Lachaume ◽  
François Trudeau ◽  
Jean Lemoyne
Keyword(s):  
Heart Rate ◽  
Oxygen Consumption ◽  
Energy Expenditure ◽  
Ice Hockey ◽  
Training Method ◽  
Hockey Players ◽  
Treadmill Testing ◽  
Effective Training ◽  
Relationship Of ◽  
The Relationship

The purpose of this study was to investigate the energy expenditure and heart rate responses elicited in elite male midget ice hockey players during small-sided games. Nine players (aged 15.89 ± 0.33 years) participated in the study. Maximal progressive treadmill testing in the laboratory measured the relationship of oxygen consumption ([Formula: see text]) to heart rate before on-ice assessments of heart rate during six different small-sided games: 1v1, 2v2, 2v2 with support player, 3v3 with support player, 3v3 with transitions, and 4v4 with two support players. Heart rate was recorded continuously in each game. 3v3 T small-sided game was the most intense for all four intensity markers. All six small-sided games reached 89% HRmax or more with heart rate peaks in active effort repetition. These findings demonstrate that such small-sided games are considered as high intensity games and are an effective training method for ice hockey players.

scholarly journals Demam pada Penggunaan Analgesia Persalinan Epidural

2020 ◽  
Vol 1 (1) ◽  
pp. 72-9
Author(s):  
Alfan Mahdi Nugroho ◽  
Yusmein Uyun ◽  
Annemarie Chrysantia Melati
Keyword(s):  
Heart Rate ◽  
Cardiac Output ◽  
Oxygen Consumption ◽  
Epidural Analgesia ◽  
Neonatal Seizure ◽  
Increased Temperature ◽  
Fetal Infection ◽  
Labour Epidural Analgesia ◽  
Clinical Consequences ◽  
The Relationship

Analgesia epidural telah diperkenalkan secara rutin sebagai salah satu modalitas analgesia pada proses persalinan sejak lama. Hubungan antara analgesia epidural persalinan dengan demam intrapartum pada maternal sudah disebutkan pada beberapa literatur. Demam didefinisikan sebagai peningkatan suhu tubuh lebih dari 38 oC yang didapat dari dua kali pemeriksaan. Beberapa teori yang disebutkan antara lain perubahan termoregulasi, infeksi pada ibu-janin dan inflamasi non-infeksi yang dimediasi oleh sitokin proinflamasi. Namun demikian berbagai mekanisme analgesia epidural dapat menyebabkan demam masih terus diteliti. Identifikasi demam pada ibu saat persalinan merupakan hal yang penting untuk dilakukan karena memiliki konsekuensi klinis pada ibu dan neonatus. Pada ibu ditemukan suhu yang meningkat dikaitkan dengan peningkatan denyut jantung ibu, curah jantung, konsumsi oksigen, dan produksi katekolamin. Sedangkan pada janin demam intrapartum dapat menyebabkan sepsis, perubahan skor APGAR, peningkatan kebutuhan bantuan napas dan kejadian kejang. Efek demam pada ibu dan janin masih terus dipelajari, sehingga suatu saat didapatkan cara pencegahan yang paling baik yang pada akhirnya menghindarkan keraguan untuk melakukan analgesia persalinan.   Fever during labour epidural analgesia Abstract Epidural analgesia has been routinely introduced as one of the analgesia modalities during labour. Literature has mentioned the relationship between epidural analgesia and intrapartum fever among mothers. Fever is defined as increased temperature above 38 oC in more than two measurements. Several theories have been proposed, inculing thermoregulation changes, mother-fetal infection, and non-infectious inflammation mediated by proinflammatory cytokines. However, these mechanisms have been continued to evolve. Fever identification in pregnant women is essential to recognize clinical consequences to both mothers and neonates. Increased temperature in mothers is associated with increased heart rate, cardiac output, oxygen consumption, and catecholamines production. Meanwhile, in neonates intrapartum fever is related to sepsis, APGAR score changes, the need of respiratory support and incidence of neonatal seizure. Therefore, these consequences are extensively studied in order to determine the appropriate prevention.

Ischemia-induced and reperfusion-induced arrhythmias: importance of heart rate

1989 ◽  
Vol 256 (1) ◽  
pp. H21-H31 ◽  
Author(s):  
M. Bernier ◽  
M. J. Curtis ◽  
D. J. Hearse
Keyword(s):  
Heart Rate ◽  
Coronary Occlusion ◽  
Ischemia And Reperfusion ◽  
Rate Of Development ◽  
Rate Dependent ◽  
Rat Hearts ◽  
Wide Range ◽  
The Right ◽  
The Relationship ◽  
Isolated Rat

The relationship between heart rate and ischemia-induced and reperfusion-induced arrhythmias was studied using 573 isolated rat hearts. Hearts (12/group), subjected to 7 min of coronary occlusion and 10 min reperfusion, were paced at 300, 330, 360, 390, 420, 480, or 540 beats/min. Pacing either throughout the experiment or during ischemia alone led to a rate-dependent increase in the incidence of reperfusion-induced ventricular fibrillation (VF) from 25% in the unpaced hearts to greater than 90% when the rate was 420 beats/min or higher. However, pacing during reperfusion alone did not increase the incidence of reperfusion-induced VF. In separate hearts, the right atrium was removed to permit examination of both low and high rates (167 +/- 2, 240, 336 +/- 3, or 480 beats/min throughout the experiment) over a wide range of durations of occlusion (3, 5, 7, 10, 15, 20, or 40 min). Ischemia-induced VF incidence was critically dependent on heart rate, low rates being protective. During reperfusion, the incidence of VF was also highly rate dependent if reperfusion was initiated within 10 min of the onset of ischemia (ranging from 8% when rate was 167 +/- 2 beats/min to 100% when rate was 480 beats/min) but was unrelated to heart rate when reperfusion occurred at later times (ranging from 33 to 50% when ischemia duration was 40 min). Heart rate can therefore influence susceptibility to ischemia- and reperfusion-induced arrhythmias, probably as a result of an effect on the rate of development of ischemic injury.

Heart rate as an indicator of oxygen consumption: influence of body condition in the king penguin

2001 ◽  
Vol 204 (12) ◽  
pp. 2133-2144 ◽  
Author(s):  
G. Froget ◽  
P. J. Butler ◽  
Y. Handrich ◽  
A. J. Woakes
Keyword(s):  
Heart Rate ◽  
Oxygen Consumption ◽  
Body Condition ◽  
Active Oxygen ◽  
The Body ◽  
Regression Equations ◽  
Oxygen Pulse ◽  
Rate Of Oxygen Consumption ◽  
The Impact ◽  
The Relationship

SUMMARY The use of heart rate to estimate field metabolic rate has become a more widely used technique. However, this method also has some limitations, among which is the possible impact that several variables such as sex, body condition (i.e. body fat stores) and/or inactivity might have on the relationship between heart rate and rate of oxygen consumption. In the present study, we investigate the extent to which body condition can affect the use of heart rate as an indicator of the rate of oxygen consumption. Twenty-two breeding king penguins (Aptenodytes patagonicus) were exercised on a variable-speed treadmill. These birds were allocated to four groups according to their sex and whether or not they had been fasting. Linear regression equations were used to describe the relationship between heart rate and the rate of oxygen consumption for each group. There were significant differences between the regression equations for the four groups. Good relationships were obtained between resting and active oxygen pulses and an index of the body condition of the birds. Validation experiments on six courting king penguins showed that the use of a combination of resting oxygen pulse and active oxygen pulse gave the best estimate of the rate of oxygen consumption V̇O2. The mean percentage error between predicted and measured V̇O2 was only +0.81% for the six birds. We conclude that heart rate can be used to estimate rate of oxygen consumption in free-ranging king penguins even over a small time scale (30min). However, (i) the type of activity of the bird must be known and (ii) the body condition of the bird must be accurately determined. More investigations on the impact of fasting and/or inactivity on this relationship are required to refine these estimates further.

The heart rate/oxygen consumption relationship during cold exposure of the king penguin: a comparison with that during exercise

2002 ◽  
Vol 205 (16) ◽  
pp. 2511-2517 ◽  
Author(s):  
G. Froget ◽  
Y. Handrich ◽  
Y. Le Maho ◽  
J.-L. Rouanet ◽  
A. J. Woakes ◽  
...  
Keyword(s):  
Heart Rate ◽  
Oxygen Consumption ◽  
Critical Temperature ◽  
Body Condition ◽  
Heart Beat ◽  
Lower Critical Temperature ◽  
Rate Of Oxygen Consumption ◽  
Free Ranging ◽  
The Relationship ◽  
Environmental Temperatures

SUMMARY This study investigated whether exposure to low ambient temperature could be used as an alternative to exercise for calibrating heart rate (fH)against rate of oxygen consumption(V̇O2) for subsequent use of fH to estimate V̇O2 in free-ranging animals. Using the relationship between the oxygen pulse (OP, the amount of oxygen used per heart beat) and an index of body condition (or nutritional index, NI), a relationship between fH and V̇O2 was established for resting king penguins exposed to a variety of environmental temperatures. Although there was a small but significant increase in the OP above and below the lower critical temperature (-4.9°C), there was no difference in the relationship obtained between the OP and body condition (NI)obtained above or below the lower critical temperature. These results were then compared with those obtained in a previous study in which the relationship between fH and V̇O2 had been established for king penguins during steady-state exercise. The relationship between OP and NI in the present study was not significantly different from the relationship between resting OP and NI in the previous study. However, the relationship was different from that between active OP and NI. We conclude that, at least for king penguins, although thermoregulation does not affect the relationship between resting OP and NI, temperature cannot be used as an alternative to exercise for calibrating fH against V̇O2 for subsequent use of fH to estimate V̇O2 in free-ranging animals.

A Model for the Relationship Between the Arterial Pressure and the Heart Period

1989 ◽  
Vol 111 (4) ◽  
pp. 336-341
Author(s):  
F. Iacovelli ◽  
M. Napolitano ◽  
A. Federici ◽  
G. Sorrentino
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Arterial Blood ◽  
Average Blood Pressure ◽  
Wide Range ◽  
Theoretical Predictions ◽  
Heart Cycle ◽  
Physiological Values ◽  
Experimental Values ◽  
The Relationship

This paper provides a simple model for predicting the relationship between steadystate heart rate and arterial blood pressure. Two current state-of-the-art models of the cardiovascular system as a pump operating in its circuit are reformulated and combined in order to highlight the role of the duration of the heart cycle. The proposed model establishes that the cardiac cycle lengthens linearly with the inverse of the average blood pressure. Experimental data are reported for sixteen preoperated conscious dogs resting quietly on their sides. Vagal and sympathetic blocks have been produced in four dogs in order to obtain a wide range of sympathetic and parasympathetic tones, namely, to cover the entire range of physiological values of the heart rate. For these dogs a comparison between the experimental values and the theoretical predictions shows a good agreement, the results of the linear regression model being statistically significant at the p = 0.001 level for three dogs and at the p = 0.01 level for the fourth dog.

An Evaluation of EMG of the Frontalis Muscle as an Indicator of Change of Workload — A Pilot Study

1976 ◽  
Vol 20 (23) ◽  
pp. i-xi
Author(s):  
David J. Cochran ◽  
Ganesh Maddali
Keyword(s):  
Heart Rate ◽  
Oxygen Consumption ◽  
Pilot Study ◽  
Mild Stress ◽  
Physical Effort ◽  
Frontalis Muscle ◽  
Stress Changes ◽  
The Relationship

Evaluation of a person's overall physical effort has traditionally been performed by measuring such easily quantifiable parameters as heart rate and oxygen consumption. Electromyography of a particular muscle, while being an acknowledged indicator of the amount of effort of that muscle, may not necessarily be an indicator of overall physical effort. Research conducted in recent years tends to show that mild stress changes were reflected in the EMG of the frontalis. This study is an attempt at seeking a relationship between the EMG of the frontalis and the workload. Heart rate and frontalis EMG were recorded at three different rates of work. Results indicate that the relationship between workload and heart rate is significant, while that between workload and frontalis EMG is not significant.

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