Comparative responses of arterial oxygen saturation and heart rate during postnatal development in rats living at high and low altitude.

More than 140 million people are living at high altitude worldwide. An increase of pulmonary artery pressure (PAP) is a hallmark of high-altitude exposure and, if pronounced, may be associated with important morbidity and mortality. Surprisingly, there is little information on the usual PAP in high-altitude populations. We, therefore, conducted a systematic review (MEDLINE and EMBASE) and meta-analysis of studies published (in English or Spanish) between 2000 and 2015 on echocardiographic estimations of PAP and measurements of arterial oxygen saturation in apparently healthy participants from general populations of high-altitude dwellers (>2,500 m). For comparison, we similarly analyzed data published on these variables during the same period for populations living at low altitude. Twelve high-altitude studies comprising 834 participants and 18 low-altitude studies (710 participants) fulfilled the inclusion criteria. All but one high-altitude studies were performed between 3,600 and 4,350 m. The combined mean systolic PAP (right ventricular-to-right atrial pressure gradient) at high altitude [25.3 mmHg, 95% confidence interval (CI) 24.0, 26.7], as expected was significantly (P < 0.001) higher than at low altitude (18.4 mmHg, 95% CI 17.1,19.7), and arterial oxygen saturation was significantly lower (90.4%, 95% CI 89.3, 91.5) than at low altitude (98.1%; 95% CI 97.7, 98.4). These findings indicate that at an altitude where the very large majority of high-altitude populations are living, pulmonary hypertension appears to be rare. The reference values and distributions for PAP and arterial oxygen saturation in apparently healthy high-altitude dwellers provided by this meta-analysis will be useful to future studies on the adjustments to high altitude in humans.

Download Full-text

Effect of Oxygen Treatment on Heart Rate after Abdominal Surgery

Anesthesiology ◽

10.1097/00000542-199902000-00008 ◽

1999 ◽

Vol 90 (2) ◽

pp. 380-384 ◽

Cited By ~ 27

Author(s):

Susan Rosenberg-Adamsen ◽

Claus Lie ◽

Anne Bernhard ◽

Henrik Kehlet ◽

Jacob Rosenberg

Keyword(s):

Heart Rate ◽

Abdominal Surgery ◽

Oxygen Saturation ◽

Oxygen Therapy ◽

Arterial Oxygen Saturation ◽

Arterial Oxygen ◽

Cardiac Complications ◽

Oxygen Supplementation ◽

Unselected Group ◽

Effect Of Oxygen

Background Cardiac complications are common during the postoperative period and may be associated with hypoxemia and tachycardia. Preliminary studies in high-risk patients after operation have shown a possible beneficial effect of oxygen therapy on arterial oxygen saturation and heart rate. Methods The authors studied the effect of oxygen therapy on arterial oxygen saturation and heart rate in 100 consecutive unselected patients randomly and double blindly allocated to receive air or oxygen therapy between the first and fourth day after major abdominal surgery. Results The median arterial oxygen saturation rate increased significantly from 96% to 99% (P < 0.0001) and the heart rate decreased significantly from 85 beats/min to 81 beats/min (P < 0.0001) during oxygen supplementation compared with air administered by a binasal catheter. The greatest decrease in heart rate occurred in patients with the lowest oxygen saturation or the highest heart rate values before oxygen supplementation. Overall, 73% of this unselected group of patients responded with decreased heart rate during supplemental oxygen therapy. No significant differences in changes in heart rate after oxygen supplementation were found between patients with or without an epidural catheter or between the postoperative day studied. Conclusion Postoperative oxygen therapy increased arterial oxygen saturation and decreased heart rate after uncomplicated abdominal surgery in a consecutive unselected group of patients who received routine postoperative care.

Download Full-text

Comparison the Sedation Effect and Satisfaction of Two Combinations, Dexmedetomidine and Fentanyl with Midazolam and Fentanyl, in Patients Undergoing Bronchoscopy

Journal of Contemporary Medical Sciences ◽

10.22317/jcms.v6i6.856 ◽

2021 ◽

Vol 6 (6) ◽

Author(s):

Alireza Kamali ◽

Sepideh Sarkhosh ◽

Hosein Kazemizadeh

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Oxygen Saturation ◽

Statistical Tests ◽

Arterial Oxygen Saturation ◽

Mean Blood Pressure ◽

Arterial Oxygen ◽

P Value ◽

Double Blind ◽

Significant Difference

Objectives: The aim of this study was to compare sedative effects of dexmedetomidine and fentanyl with midazolam and fentanyl in patients undergoing bronchoscopy. Methods: This study was a double-blind randomized clinical trial that was performed on 92 patients who referred to Amir al Momenin Hospital in Arak for bronchoscopy and underwent ASA 1 or 2 underlying grading procedure. Patients were randomly divided into two groups of dexmedetomidine and fentanyl (D) midazolam and fentanyl (M). Primary vital signs including hypertension and arterial oxygen saturation were monitored and recorded. Then all patients were injected with 2 μg / kg fentanyl as a painkiller and after 3 minutes 30 μg dexmedetomidine in syringe with code A and midazolam 3 mg in syringe with code B were injected to patients by an anesthesiologist. Then the two groups were compared in terms of pain at injection, conscious relaxation, satisfaction of operation, recovery time, hypotension and arterial oxygen saturation and drug side effects and data were analyzed by using statistical tests. Results: There was no significant difference between the two groups in terms of mean age and sex distribution. According to the results of this study, there was no significant difference between the two groups in mean blood pressure (P-value = 0.6) and mean heart rate (P-value = 0.4) at the time of bronchoscopy, but at 5 and 10 minutes after bronchoscopy there was a significant difference, mean blood pressure and heart rate were significantly lower in dexmedetomidine group. Conclusion: Both dexmedetomidine and midazolam drug groups contributed to the development of stable and sedative hemodynamics and satisfaction in patients undergoing bronchoscopy, however, the dexmedetomidine and fentanyl group showed a significant decrease in blood pressure and heart rate compared to midazolam and fentanyl and a weaker decrease in arterial oxygen saturation, and patients with bronchoscopy were more satisfied in the dexmedetomidine group.

Download Full-text

Arterial Oxygen Saturation and Heart Rate Variation During Breath-Holding: Comparison between Breath-Hold Divers and Controls

International Journal of Sports Medicine ◽

10.1055/s-2004-820976 ◽

2005 ◽

Vol 26 (3) ◽

pp. 177-181 ◽

Cited By ~ 10

Author(s):

J. Delahoche ◽

P. Delapille ◽

F. Lemaître ◽

E. Verin ◽

C. Tourny-Chollet

Keyword(s):

Heart Rate ◽

Oxygen Saturation ◽

Arterial Oxygen Saturation ◽

Arterial Oxygen ◽

Breath Holding ◽

Breath Hold ◽

Rate Variation ◽

Heart Rate Variation

Download Full-text

Effects of a closed tracheal suction system on ventilatory and cardiovascular parameters

American Journal of Critical Care ◽

10.4037/ajcc1992.1.3.57 ◽

1992 ◽

Vol 1 (3) ◽

pp. 57-61 ◽

Cited By ~ 18

Author(s):

SA Harshbarger ◽

LA Hoffman ◽

TG Zullo ◽

MR Pinsky

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Oxygen Saturation ◽

Respiratory Rate ◽

Arterial Oxygen Saturation ◽

Control Mode ◽

Arterial Oxygen ◽

Acid Base ◽

Suction System ◽

Repeated Measures Design

OBJECTIVE: To determine whether patients ventilated in the assist-control mode experienced a change in oxygenation, respiratory rate, inspiratory:expiratory ratio, heart rate, blood pressure or acid-base balance when suctioned with a closed tracheal suction system. DESIGN: A quasi-experimental, within-subject, repeated-measures design was used. SUBJECTS: 18 patients ventilated on a fraction of inspired oxygen of 0.47 +/- 0.17 and 2.3 +/- 5.0 cm H2O positive end-expiratory pressure. INTERVENTIONS: Two suction passes were performed, with measurements at baseline, immediately after the first suction pass, immediately before the second suction pass, immediately after the second suction pass, 2 minutes after the second suction pass and 5 minutes after the second suction pass. No hyperoxygenation was used. RESULTS: Significant differences were seen over time for arterial oxygen saturation, respiratory rate and inspiratory:expiratory ratio. Arterial oxygen saturation decreased to less than 90% in four subjects (range 88% to 89%), with a maximum fall of 9%. No significant differences were seen for heart rate, blood pressure, partial pressure of carbon dioxide, bicarbonate, time to nadir (lowest arterial oxygen saturation) or recovery time. CONCLUSIONS: Subjects ventilated in the assist-control mode and suctioned with a closed tracheal suction system did not experience significant changes in cardiovascular or acid-base parameters when suctioned without hyperoxygenation. Although most subjects did not become desaturated, four subjects experienced desaturation at one or more intervals. To prevent desaturation, hyperoxygenation should be used before and after suctioning with a closed tracheal suction system.

Download Full-text

Oxygen Saturation and Breathing Patterns in Children

PEDIATRICS ◽

10.1542/peds.92.5.686 ◽

1993 ◽

Vol 92 (5) ◽

pp. 686-690 ◽

Cited By ~ 3

Author(s):

Christian F. Poets ◽

Valerie A. Stebbens ◽

Martin P. Samuels ◽

David P. Southall

Keyword(s):

Heart Rate ◽

Oxygen Saturation ◽

Respiratory Rate ◽

Arterial Oxygen Saturation ◽

Respiratory Control ◽

Arterial Oxygen ◽

Baseline Heart Rate ◽

Healthy Children ◽

Breathing Patterns ◽

Beat Mode

Objective. To obtain information on breathing patterns and oxygenation in children. Design. Overnight tape recordings of arterial oxygen saturation (Sao2 Nellcor N200 in beat-to-beat mode), photoplethysmographic waveforms, and breathing movements in 70 healthy children (mean age 8.0 years, range 2 through 16). Analysis of recordings for pauses in breathing movements of ≥4 seconds (apneic pauses), for episodes in which Sao2 fell to ≤90% (desaturations) and, only during the state of regular breathing, for baseline Sao2 heart rate, and respiratory rate. Results. Both baseline heart rate and respiratory rate decreased with increasing age (r = –.7 and –.3, respectively, P < .01). Baseline Sao2 was similar to that previously observed in infants (median 99.5%, range 95.8 to 100, 5th centile 96.6%). Every recording showed apneic pauses, with a frequency that did not vary consistently with age (median 7.7/h, range 0.6 to 25.5). One hundred nineteen apneic pauses in 43 recordings lasted for 15 to 19.9 seconds, and 23 lasted for ≥20 seconds (longest 28.8 seconds). The number of episodic falls in Sao2 to ≥90% decreased with age (r = –.3, P < .01); such episodes were found in 47% of children aged 2 through 6 years, but in only 13% of those aged 12 through 16 years. The 95th centile for desaturation frequency in the total group was 0.6/h. In six episodes in four patients, Sao2 fell to ≤80%. Conclusions. Apneic pauses, some of which can last for more than 20 seconds, are a normal phenomenon in healthy children and adolescents, but only a small minority of apneic pauses affect blood gas homeostasis. Information concerning oxygenation may be more relevant to our understanding of the maturation of respiratory control than the recording of breathing signals alone.

Download Full-text