Circulatory adjustment in pearl divers

1962 ◽  
Vol 17 (2) ◽  
pp. 184-190 ◽  
Author(s):  
P. F. Scholander ◽  
H. T. Hammel ◽  
H. LeMessurier ◽  
E. Hemmingsen ◽  
W. Garey
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Lactic Acid ◽  
Energy Metabolism ◽  
Blood Lactate ◽  
Cardiac Arrhythmias ◽  
General Feature ◽  
Fetal Bradycardia ◽  
Visceral Organs ◽  
Native Skin

A seemingly general feature in the adjustment to diving in various mammals, birds, and reptiles is a slow-down and redistribution of the circulation, leaving muscles, periphery, and certain visceral organs with a markedly reduced circulation. This saves oxygen and causes widespread reduction of the energy metabolism. Active as well as quiet diving develops bradycardia without drop in central blood pressure, and lactic acid forming in the muscles during the dive floods the blood when breathing starts. In 31 native skin divers in Australia, diving rarely exceeded 1 min. During the dive, blood pressure stayed normal while heart rate dropped to half; blood lactate (five divers) remained normal but showed an acute rise in the recovery. Evidently humans utilize an adjustment similar to animals. Most of our divers developed various cardiac arrhythmias during the dive, persisting sometimes into the beginning of the recovery. This asphyxial defense seems developed at birth, for fetal bradycardia is common during delivery, and an acute rise of lactic acid after delivery has recently been described. Phylogenetically the mechanism is ancient, for it is found also in fishes when taken out of water. Submitted on August 7, 1961

Electrocardiographic and arterial pressure changes in female dogs subjected to epidural anesthesia with different doses of morphine

2017 ◽  
Vol XXII (130) ◽  
pp. 60-70
Author(s):  
Mariana Werneck Fonseca ◽  
Verônica Batista de Albuquerque ◽  
Gabriel T. N. Martins Ferreira ◽  
Marcelo Augusto de Araújo ◽  
Wagner Luis Ferreira ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Arterial Pressure ◽  
Systolic Blood Pressure ◽  
Blood Lactate ◽  
Rectal Temperature ◽  
Epidural Anesthesia ◽  
Epidural Morphine ◽  
Pressure Changes ◽  
Different Doses

This article investigates the electrocardiographic and blood pressure changes caused by different doses of morphine administered epidurally to bitches undergoing elective ovariohysterectomy. Twenty-four healthy bitches weighing 9.8 ± 4.1 kg were assigned to three experimental groups (in each group, n = 8): (i) group M0.1: 0.1 mg/kg morphine; (ii) group M0.15: 0.15 mg/kg morphine; and (iii) group M0.2: 0.2 mg/kg morphine. In all groups, levobupivacaine was added to achieve a total volume of 0.33 mL/kg. During the procedures, the following parameters were controlled: heart rate and rhythm, systolic blood pressure, rectal temperature and blood lactate. The data were analyzed by means of statistical methods of analysis of variance, such as Kruskal-Wallis, Fisher and Tukey tests. Epidural morphine did not cause significant electrocardiographic or blood pressure changes in the tested doses, which makes the use of this drug a viable alternative for epidural anesthesia.

scholarly journals Electrocardiographic Changes in Elderly Patients During Endoscopic Retrograde Cholangiopancreatography

2003 ◽  
Vol 17 (9) ◽  
pp. 539-544 ◽  
Author(s):  
NG Kounis ◽  
GM Zavras ◽  
PJ Papadaki ◽  
SN Kouni ◽  
M Batsolaki ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Myocardial Ischemia ◽  
Elderly Patients ◽  
Endoscopic Retrograde Cholangiopancreatography ◽  
Cardiac Arrhythmias ◽  
Holter Monitoring ◽  
Endoscopic Retrograde ◽  
St Segment ◽  
Ectopic Beats

BACKGROUND: Cardiorespiratory complications may occur during gastrointestinal endoscopy, and elderly people seem to be more vulnerable to these complications during endoscopic procedures involving the manipulation of abdominal viscera. OBJECTIVES: To determine the incidence of cardiac arrhythmias, changes in oxygen saturation, heart rate and blood pressure during endoscopic retrograde cholangiopancreatography (ERCP) via Holter monitoring in elderly patients older than 70 years of age.METHODS: Holter monitoring and 12-lead electrocardiograms were performed in 30 elderly patients undergoing ERCP and in 30 control subjects undergoing routine chest, abdomen, bone and upper gastrointestinal small bowel follow-through studies. A computerized nontriggered template system was used to analyze the electrocardiograms qualitatively and quantitatively. Arrhythmias, cardiac axis, conduction defects, pauses, ST segment changes, ectopic beats, oxygen desaturation and changes in blood pressure and rate-pressure product were evaluated.RESULTS: Increased heart rate, ST segment changes resulting from myocardial ischemia, oxygen desaturation and transient atrial and ventricular ectopic beats were frequent during ERCP compared with the control group. In one patient, transient left bundle branch block developed and this was attributed to pre-existing hypertension with cardiomegaly. One patient developed ventricular tachycardia and one other sinus bradycardia, but this was attributed to sick sinus syndrome.CONCLUSIONS: Transient myocardial ischemia and various cardiac arrhythmias are frequent in elderly patients undergoing ERCP. Appropriate noninvasive monitoring seems to be justified during this procedure.

Lack of heart rate variation between morning and afternoon exercise testing in coronary artery disease patients

1993 ◽  
Vol 74 (3) ◽  
pp. 1012-1015 ◽  
Author(s):  
J. D. Marriott ◽  
L. H. Hartley ◽  
J. Sherwood
Keyword(s):  
Blood Pressure ◽  
Coronary Artery Disease ◽  
Heart Rate ◽  
Lactic Acid ◽  
Oxygen Uptake ◽  
Blood Plasma ◽  
Early Morning ◽  
Lactic Acid Concentration ◽  
Late Afternoon ◽  
Artery Disease

The purpose of this study was to investigate cardiovascular [heart rate (HR), blood pressures, rate-pressure product (RPP)], physiological (oxygen uptake), and metabolic (blood plasma lactic acid concentration) responses during symptom-limited graded exercise testing (SL-GXT) during early morning and late afternoon hours in an unmedicated, regularly exercising, coronary artery disease population. Subjects, males ages 41–71 yr (n = 11), underwent SL-GXT via cycle ergometry at 8:30 A.M. and 4:30 P.M. HR, systolic blood pressure, diastolic blood pressure, and RPP were evaluated at rest and at submaximal and peak work. Oxygen uptake and rate of perceived exertion were also determined at submaximal and peak power output, with blood plasma lactic acid concentration measured at peak work. Data, analyzed by the paired t test, failed to demonstrate any significant variation in HR, systolic blood pressure, diastolic blood pressure, RPP, or blood plasma lactic acid responses during exercise at the two points used. Oxygen uptake did not significantly change at any submaximal intensity. Thus SL-GXT results obtained at early morning (8:30 A.M.) and late afternoon (4:30 P.M.) are a reproducible, reliable means of prescribing exercise HR and work intensities.

Intravenous acid infusion stimulates ACTH secretion in sheep

1991 ◽  
Vol 260 (1) ◽  
pp. E154-E161 ◽  
Author(s):  
C. E. Wood ◽  
A. Isa
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Lactic Acid ◽  
Plasma Renin Activity ◽  
Vena Cava ◽  
Plasma Renin ◽  
Renin Activity ◽  
Acth Secretion ◽  
Reflex Responses ◽  
Arterial Blood

Both respiratory and metabolic acidemia stimulate the secretion of adrenocorticotropic hormone (ACTH), vasopressin, and renin. The present study was designed to test the blood pressure, heart rate, and endocrine responses of conscious sheep to low-rate infusions of H+. We infused HCl and lactic acid at a rate of 500 mueq/min into the inferior vena cava of seven chronically catheterized adult sheep. Control experiments in six sheep consisted of infusion of HCl at a rate of 100 mueq/min. Only the 500 mueq/min infusion of HCl stimulated reflex responses. This infusion increased mean arterial blood pressure and plasma ACTH concentration but transiently decreased blood pH only after the onset of the reflex responses. Heart rate appeared to increase initially but then decreased. Overall, the apparent changes in heart rate were not statistically significant. None of the infusions significantly altered plasma renin activity or vasopressin concentration. We speculate that heart rate, plasma renin activity, and vasopressin may have been partially inhibited by the increase in blood pressure. However, the lack of effect of lactic acid suggests that the HCl stimulated reflex ACTH and blood pressure responses via a mechanism not related to the concentration of the acid in the infusate or to the total amount of acid infused. It is possible that HCl, but not lactic acid, stimulated release of a humoral agent that stimulated ACTH secretion directly or reflexly. The results do not appear consistent with the stimulation of a venous chemoreceptor sensitive to H+.

scholarly journals Comparison of diagnostic methods for hemodynamic treatment in unborn and pre-term infants using the measurement of vena cava, lactate, and clinical criteria

10.52011/81 ◽  
2021 ◽  
Vol 22 (3) ◽  
pp. 1-9
Author(s):  
Geyson Deley-Muñoz ◽  
Fabricio González-Andrade
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Lactic Acid ◽  
Birth Weight ◽  
Preterm Infants ◽  
Vena Cava ◽  
Urinary Output ◽  
Clinical Criteria ◽  
Capillary Filling ◽  
Hemodynamic State

Introduction: There is no single criterion available to assess the hemodynamic state of new-born infants and preterm infants and the different variables in the group of newborns, such as gestational age, birth weight, and periods of birth. Methods: This is an epidemiological, cross-sectional, descriptive observational study with two patient cohorts. Newborn-to-term and preterm neonates assisted at the Neonatal Unit of the Pablo Arturo Suarez Hospital participated during the months between November 2019 to January 2020. Results: Ultrasound measurement of the vena cava (FVC) flow is useful for the management treatment of hemodynamically unstable neonatal patients. The sample was made up of 110 newborns treated in the Pablo Arturo Suarez Hospital's neonatology service from November 2019 to January 2020. Quito, Pichincha, Ecuador. The variables low birth weight and moder-ate prematurity have a statistically significant value for inotropic use. The other variables do not present statistically significant values. Heart rate, urinary output, mean blood pressure, lactic acid, capillary filling, upper vena cava flow, and lower vena cava flow had statistically significant values. FVCI and FVCS comparisons with heart rate, urinary output, mean blood pressure, lactic acid, and capillary filling had statistically significant values, except for capil-lary filling> 3 sec in FCVI. Multivariate analysis of categorical main components (CATPCA) was used to characterize the hemodynamic state and inotropic state, which were significant in the bivariate analysis. Dimension, one of the two-dimensional graphs, discriminates the use or not of inotropics and the categories of hemodynamic parameters TAM <35 mmHg, lactic acid, capillary filling, FVCI, and FVCS. Dimension II discriminates between the categories of urinary expenditure and HR. Conclusion: In term and preterm infants with low weight and adequate birth weight with hemodynamic instability in general, who were evaluated with ultrasonography to measure the flow of the vena cava, the agreement between the clinical criteria and the ultrasound assessment of the flow was 0.4 cm/sec in both methods. This situation means that the measurement of venous cava flows by echo sonography is useful for assessing neonatal patients' hemodynamic status.

scholarly journals Comparison of Physiological and Perceptual Responses Between Continuous and Intermittent Cycling

2011 ◽  
Vol 29A (Special-Issue) ◽  
pp. 59-68 ◽  
Author(s):  
Roxana Brasil ◽  
Ana Barreto ◽  
Leandro Nogueira ◽  
Edil Santos ◽  
Jefferson Novaes ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Blood Lactate ◽  
Arterial Blood Pressure ◽  
Perceived Exertion ◽  
Lactate Concentration ◽  
Blood Lactate Concentration ◽  
Double Product ◽  
Arterial Blood ◽  
Rate Of Perceived Exertion

Comparison of Physiological and Perceptual Responses Between Continuous and Intermittent CyclingThe present study tested the hypothesis that the exercise protocol (continuous vs. intermittent) would affect the physiological response and the perception of effort during aquatic cycling. Each protocol was divided on four stages. Heart rate, arterial blood pressure, blood lactate concentration, central and peripheral rate of perceived exertion were collected in both protocols in aquatic cycling in 10 women (values are mean ± SD): age=32.8 ± 4.8 years; height=1.62 ± 0.05 cm; body mass=61.60 ± 5.19 kg; estimated body fat=27.13 ± 4.92%. Protocols were compared through two way ANOVA with Scheffé's post-hoc test and the test of Mann- Whitney for rate of perceived exertion with α=0.05. No systematic and consistent differences in heart rate, arterial blood pressure, double product and blood lactate concentration were found between protocols. On the other hand, central rate of perceived exertion was significantly higher at stage four during continuous protocol compared with intermittent protocol (p=0.01), while the peripheral rate of perceived exertion presented higher values at stages three (p=0.02) and four (p=0.00) in the continuous protocol when compared to the results found in intermittent protocol. These findings suggest that although the aquatic cycling induces similar physiologic demands in both protocols, the rate of perceived exertion may vary according to the continuous vs. intermittent nature of the exercise.

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