Monitoring Carbon Dioxide Tension and Arterial Oxygen Saturation by a Single Earlobe Sensor in Patients With Critical Illness or Sleep Apnea

AbstractAmbulatory blood pressure monitoring and parallel polysomnographic study were performed in 116 adult males divided into 6 groups. Thirty blood-pressure (BP) and polysomnographic variables were measured to test their usefulness for screening for both arterial hypertension and sleep apnea-hypopnea syndrome (SAHS). The development of severe breathing disorders and hypoxemia during sleep was attributed to SAHS, when compared with measurements in healthy controls and in patients with arterial hypertension. Such disorders manifested as an increased apnea-hypopnea index, apnea index, duration of arterial oxygen saturation of less than 85%, and decrease of average arterial oxygen saturation that correlated with nocturnal average diastolic BP (p=0.0049, p=0.0027, p=0.049 and p=0.0457, respectively). These respiratory disorders resulted in various nocturnal, rather than diurnal, and diastolic and systolic BP variables. The acute antihypertensive effect of continuous positive airway pressure therapy for SAHS significantly reduced the episodes of apnea and hypopnea and the secondary component of hypertension caused by excessive sympathetic stimulation. For the SAHS-induced, dose-dependent component of hypertension that responded to continuous positive airway pressure, the following variables, in decreasing significance, were useful: nocturnal average systolic and diastolic BP and 24-hour average systolic and diastolic BP, as well as percent time elevation and mean blood pressure load. The monitoring of these variables could contribute to early diagnostic and prognostic stratification of complications and adequate therapy of the secondary component of hypertension caused by SAHS.

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Comparison of Intra and Post-operative Sedation efficacy of Dexmedetomidine-Midazolam and Dexmedetomidine-Propofol for Major Abdominal Surgery

Current Drug Metabolism ◽

10.2174/1389200222666211103121832 ◽

2021 ◽

Vol 22 ◽

Author(s):

Yuanyuan Gao ◽

Fei Yan

Keyword(s):

Clinical Trial ◽

Abdominal Surgery ◽

Oxygen Saturation ◽

General Anesthesia ◽

Arterial Oxygen Saturation ◽

Carbon Dioxide Tension ◽

Major Abdominal Surgery ◽

Arterial Oxygen ◽

Anesthesia Induction ◽

Significant Difference

Background: The effectiveness and side effects of dexmedetomidine (DEX) in combination with midazolam and propofol have not been comparatively studied in a single clinical trial as sedative agents to general anesthesia before. Objective: The objective of this study is to compare intra and post-operative sedation between DEX-Midazolam and DEX-Propofol in patients who underwent major abdominal surgery on the duration of general anesthesia, hemodynamic and sedation effect. Method: This prospective, randomized, double-blinded clinical trial included 50 patients who were 20 to 60 years of age and admitted for major abdominal surgery. The patients were randomly assigned by a computer-generated random numbers table to sedation with DEX plus midazolam (DM group) (n=25) or DEX plus propofol (DP group) (n=25). In the DM group, patients received a bolus dose of 0.1 mg/kg of midazolam and immediately initiated the intravenous (i.v.) infusion of DEX 1 µg/kg over a 10 min and 0.5 µg/kg/hr by continuous i.v. infusion within operation period. In the DP group, patients received pre-anesthetic i.v. DEX 1 µg/kg over 15 min before anesthesia induction and 0.2-1 µg/kg/hr by continuous i.v. infusion during the operative period. After preoxygenation for at least 2 min, during the surgery, patients received propofol infusion dose of 250 μg/kg/min for 15 min then a basal infusion dose of 50 μg/kg/min. The bispectral index (BIS) value, as well as mean arterial pressure (MAP), heart rate (HR), respiratory rate (RR), oxygen saturation (SaO2), percutaneous arterial oxygen saturation (SpO2) and end-tidal carbon dioxide tension (ETCO2) were recorded before anesthesia (T0), during anesthesia (at 15-min intervals throughout the surgical procedure), by a blinded observer. Evidence of apnea, hypotension, hypertension and hypoxemia were recorded during surgery. Results: The hemodynamic changes, including HR, MAP, BIS, VT, SaO2, and RR had a downward tendency with time, but no significant difference was observed between the groups (P>0.05). However, the two groups showed no significant differences in ETCO2 and SPO2 values in any of the assessed interval (P>0.05). In this study, the two groups showed no significant differences in the incidence of nausea, vomiting, coughing, apnea, hypotension, hypertension, bradycardia and hypoxemia (P>0.05). Respiratory depression and Conclusion: Our study showed no significant differences between the groups in hemodynamic and respiratory changes in each of the time intervals. There were also no significant differences between the two groups in the incidence of complication intra and post-operative. Further investigations are required to specify the optimum doses of using drugs which provide safety in cardiovascular and respiratory system without adverse disturbance during surgery.

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Poincaré analysis of an overnight arterial oxygen saturation signal applied to the diagnosis of sleep apnea hypopnea syndrome

Physiological Measurement ◽

10.1088/0967-3334/30/4/005 ◽

2009 ◽

Vol 30 (4) ◽

pp. 405-420 ◽

Cited By ~ 19

Author(s):

Daniel S Morillo ◽

Juan L Rojas ◽

Luis F Crespo ◽

Antonio León ◽

Nicole Gross

Keyword(s):

Sleep Apnea ◽

Oxygen Saturation ◽

Arterial Oxygen Saturation ◽

Arterial Oxygen ◽

Hypopnea Syndrome

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Digital Monitoring of Obstructive Sleep Apnea Using Snoring Sound and Arterial Oxygen Saturation

SLEEP ◽

10.1093/sleep/16.suppl_8.s132 ◽

1993 ◽

Vol 16 (suppl_8) ◽

pp. S132-S132 ◽

Cited By ~ 3

Author(s):

F. G. Issa ◽

D Morrison ◽

E Hadjuk ◽

R Iyer ◽

T Feroah ◽

...

Keyword(s):

Obstructive Sleep Apnea ◽

Sleep Apnea ◽

Oxygen Saturation ◽

Arterial Oxygen Saturation ◽

Arterial Oxygen ◽

Obstructive Sleep ◽

Digital Monitoring

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Electrocardiographic study on geriatric dogs undergoing general anesthesia with isoflurane

Ciência Rural ◽

10.1590/s0103-84782008005000085 ◽

2008 ◽

Vol 39 (2) ◽

pp. 453-459

Author(s):

Andreza Conti-Patara ◽

Denise Tabacchi Fantoni ◽

Silvia Renata Gaido Cortopassi

Keyword(s):

Carbon Dioxide ◽

Oxygen Saturation ◽

Partial Pressure ◽

Normal Sinus Rhythm ◽

Arterial Oxygen Saturation ◽

Carbon Dioxide Partial Pressure ◽

Arterial Oxygen ◽

T Wave ◽

Arterial Blood ◽

St Segment

The purpose of this study was to clarify the degree of influence of anesthetic agents commonly used during anesthesia on the heart conduction systems of geriatric dogs, with or without the presence of electrocardiographic changes in the pre-anesthetic electrocardiogram and also to determine the possible causes of ST-segment and T-wave changes during anesthesia, by monitoring ventilation and oxygenation. 36 geriatric dogs were evaluated. In addition to electrocardiographic evaluation, the pre-anesthetic study included serum levels of urea, creatinine, total protein, albumin and electrolytes. The pre-anesthetic medication consisted of acepromazine (0.05mg kg-1) in association with meperidine (3.0mg kg-1) by IM injection. Anesthesia was induced with propofol (3.0 to 5.0mg kg-1) by IV injection and maintained with isoflurane in 100% oxygen. During the anesthesia, the animals were monitored by continued computerized electrocardiogram. Systemic blood pressure, heart rate, respiratory rate, end-tidal carbon dioxide, partial pressure of carbon dioxide in arterial blood, arterial oxygen saturation, partial pressure of arterial oxygen and oxygen saturation of hemoglobin were closely monitored. During maintenance anesthesia, normal sinus rhythm was more common (78%). ST-segment and T-wave changes during the anesthetic procedure were quite common and were related to hypoventilation. The use of isoflurane did not result in arrhythmia, being therefore a good choice for this type of animal; Electrocardiographic findings of ST-segment and T-wave changes during the maintenance anesthesia were evident in animals with hypercapnia, a disorder that should be promptly corrected with assisted or controlled ventilation to prevent complicated arrhythmias.

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Pulse oximetry and capnography in the ICU

10.1093/med/9780199600830.003.0073 ◽

2016 ◽

Author(s):

Richard Lee

Keyword(s):

Oxygen Saturation ◽

Pulse Oximetry ◽

Error Detection ◽

Arterial Oxygen Saturation ◽

Carbon Dioxide Tension ◽

Tube Placement ◽

Arterial Oxygen ◽

Arterial Carbon Dioxide Tension ◽

Blood Gas ◽

Endotracheal Tube Placement

The estimation of arterial oxygen saturation by pulse oximetry and arterial carbon dioxide tension by capnography are vital monitoring techniques in critical care medicine, particularly during intubation, ventilation and transport. Equivalent continuous information is not otherwise available. It is important to understand the principles of measurement and limitations, for safe use and error detection. PETCO2 and oxygen saturation should be regularly checked against PaCO2 and co-oximeter SO2 obtained from the blood gas machine. The PECO2 trace informs endotracheal tube placement, ventilation, and blood flow to the lungs. It is essential their principles of estimation, the information gained and the traps in interpretation are understood.

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Effects of Inspired Hypoxic and Hypercapnic Gas Mixtures on Cerebral Oxygen Saturation in Neonates with Univentricular Heart Defects

Anesthesiology ◽

10.1097/00000542-200202000-00010 ◽

2002 ◽

Vol 96 (2) ◽

pp. 283-288 ◽

Cited By ~ 65

Author(s):

Chandra Ramamoorthy ◽

Sarah Tabbutt ◽

C. Dean Kurth ◽

James M. Steven ◽

Lisa M. Montenegro ◽

...

Keyword(s):

Carbon Dioxide ◽

Mean Arterial Pressure ◽

Oxygen Saturation ◽

Single Ventricle ◽

Cerebral Oxygenation ◽

Arterial Oxygen Saturation ◽

Cerebral Oxygen Saturation ◽

Arterial Oxygen ◽

Cerebral Oxygen ◽

Inspired Oxygen

Background Neonates with functional single ventricle often require hypoxic or hypercapnic inspired gas mixtures to reduce pulmonary overcirculation and improve systemic perfusion. Although the impact of these treatments on arterial oxygen saturation has been described, the effects on cerebral oxygenation remain uncertain. This study examined the effect of these treatments on cerebral oxygen saturation and systemic hemodynamics. Methods Neonates with single ventricle mechanically ventilated with room air were enrolled in a randomized crossover trial of 17% inspired oxygen or 3% inspired carbon dioxide. Each treatment lasted 10 min, followed by a 10-20-min washout period. Cerebral and arterial oxygen saturation were measured by cerebral and pulse oximetry, respectively. Cerebral oxygen saturation, arterial oxygen saturation, and other physiologic data were continuously recorded. Results Three percent inspired carbon dioxide increased cerebral oxygen saturation (56 +/- 13 to 68 +/- 13%; P < 0.01), whereas 17% inspired oxygen had no effect (53 +/- 13 to 53 +/- 14%; P = 0.8). Three percent inspired carbon dioxide increased the mean arterial pressure (45 +/- 8 to 50 +/- 9 mmHg; P < 0.01), whereas 17% inspired oxygen had no effect. And 3% inspired carbon dioxide decreased arterial pH and increased arterial carbon dioxide and oxygen tensions. Conclusions Inspired 3% carbon dioxide improved cerebral oxygenation and mean arterial pressure. Treatment with 17% inspired oxygen had no effect on either.

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