THE ARTERIAL OXYGEN AND CARBON DIOXIDE TENSION DURING THE POSTOPERATIVE PERIOD IN CASES OF PULMONARY RESECTIONS AND THORACOPLASTIES

Effects of dopamine and of a dopaminergic blocker, haloperidol, on the responses of carotid body chemoreceptors to hypoxia and hypercapnia were investigated in 16 anesthetized cats. Intravenous infusion of dopamine (10-20 micrograms.min-1) decreased carotid body chemoreceptor responses to hypoxia and hypercapnia. The effect was greater at higher levels of arterial oxygen and carbon dioxide tension (PaO2 and PaCO2) stimulus. Thus, the magnitude of the dopamine effect depended on the degree of both PO2- and PCO2-mediated excitation of the receptors. Haloperidol potentiated responses to both hypoxia and hypercapnia but apparently did not stimulate the receptors in the absence of these stimuli. Potentiation by haloperidol and inhibition by dopamine of excitatory effects due to PaO2 decrease and PaCO2 increase are complementary. The data suggest that chemoreception of dopamine, O2, and CO2 converge at some site in the carotid body. Persistence of hypoxic and hypercapnic responses, following dopamine-blocking doses of haloperidol, does not support the theory that regulation of dopamine release is responsible for O2 and CO2 chemoreception in carotid body of the cat.

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THE CHANGE IN THE ARTERIAL OXYGEN AND CARBON DIOXIDE TENSION DURING VOLUNTARY HYPERVENTILATION AS A TEST OF LUNG FUNCTION

Journal of Thoracic Surgery ◽

10.1016/s0096-5588(20)30992-2 ◽

1954 ◽

Vol 27 (6) ◽

pp. 541-545

Author(s):

Viking Olov Björk ◽

Henry John Hilty

Keyword(s):

Carbon Dioxide ◽

Lung Function ◽

Carbon Dioxide Tension ◽

Arterial Oxygen ◽

Voluntary Hyperventilation

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Arterial Oxygen and Carbon-Dioxide Tension in Patients with Acute Myocardial Infarction

Cardiology ◽

10.1159/000169651 ◽

1973 ◽

Vol 58 (6) ◽

pp. 335-346 ◽

Cited By ~ 7

Author(s):

C. Helmers ◽

S. Hofvendahl ◽

T. Lundman ◽

L. Mogensen ◽

O. Nyquist ◽

...

Keyword(s):

Myocardial Infarction ◽

Carbon Dioxide ◽

Acute Myocardial Infarction ◽

Carbon Dioxide Tension ◽

Arterial Oxygen

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Aortic body chemoreceptor responses to changes in PCO2 and PO2 in the cat

Journal of Applied Physiology ◽

10.1152/jappl.1979.47.4.858 ◽

1979 ◽

Vol 47 (4) ◽

pp. 858-866 ◽

Cited By ~ 15

Author(s):

S. Lahiri ◽

E. Mulligan ◽

T. Nishino ◽

A. Mokashi

Keyword(s):

Carbon Dioxide ◽

Discharge Rate ◽

Arterial Oxygen Tension ◽

Blood Gases ◽

Carbon Dioxide Tension ◽

Steady States ◽

Arterial Oxygen ◽

Arterial Blood ◽

Discharge Rates ◽

End Tidal

Responses of aortic chemoreceptor afferents to a range of arterial carbon dioxide tension (Paco2) changes at various levels of arterial oxygen tension (Pao2) were investigated in 18 cats anesthetized with alpha-chloralose and maintained at 38 degrees C. Aortic chemoreceptor activity, end-tidal oxygen pressure, end-tidal carbon dioxide pressure, and arterial blood pressure were continuously monitored. Arterial blood gases were measured in steady states. Single or a few clearly identifiable afferents were studied during changes and steady states of Pao2 and Paco2. All the aortic chemoreceptor afferent discharge rates increased with Paco2 increases from hypercapnia (10–15 Torr) to normocapnia and moderate hypercapnia (30–50 Torr) and with Pao2 decreases from above 400 to 30 Torr. Hypoxia augmented the response to Paco2 most effectively in the range of 10–40 Torr. At any Pao2, the discharge rate reached a plateau with sufficient intensity of hypercapnia. The Paco2 stimulus threshold at a Pao2 of 440 Torr was about 15 Torr, and at a Pao2 of 60 Torr it was 10 Torr. In the transition from hypocapnia to hypercapnia, responses increased gradually, usually without an overshoot. The steady-state responses to Paco2 of the majority of aortic chemoreceptors resembled those of carotid chemoreceptors. The responses of both receptors can be attributed to the same basic type of mechanism.

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Modified ultrafiltration in paediatric cardiac surgery

Perfusion ◽

10.1177/026765919801300205 ◽

1998 ◽

Vol 13 (2) ◽

pp. 105-109 ◽

Cited By ~ 16

Author(s):

Lise Schlünzen ◽

Jens Pedersen ◽

Kirsten Hjortholm ◽

Ole K Hansen ◽

Emmy Ditlevsen

Keyword(s):

Carbon Dioxide ◽

Heart Rate ◽

Cardiac Surgery ◽

Venous Pressure ◽

Systolic Arterial Pressure ◽

Carbon Dioxide Tension ◽

Arterial Oxygen ◽

Technical Problems ◽

Paediatric Cardiac Surgery ◽

Before And After

The effect of modified ultrafiltration (MUF) after cardiopulmonary bypass for paediatric cardiac surgery was evaluated in 138 children with moderate to severe congenital heart disease. The median age was 0.4 years (0 days to 6.5 years), and the weight 5.3 kg (2.2-20 kg). The operation was discontinued in six cases, three because of technical problems and three because of unstable circulation. One-hundred-and-thirty-four patients were ultrafiltrated for a median of 12 min (2-27 min) with an ultrafiltrate of median 44 ml/kg (6-118 ml/kg). Haematocrit was significantly increased from 28% (20-39%) to 36% (26-51%) and systolic arterial pressure from 56 mmHg (30-85 mmHg) to 74.0 mmHg (32-118 mmHg). Furthermore arterial oxygenation was significantly increased from 30.8 kPa (4.8-70.4 kPa) to 34.1 kPa (4.9-80.6 kPa), and arterial carbon dioxide tension from 4.8 kPa (3.1-7.3 kPa) to 5.1 kPa (3.1-7.6 kPa). Heart rate was significantly reduced from 145 beats/min (92-201 beats/min) to 136 beats/min (88-200 beats/min). There were no significant differences in central venous pressure, left atrial pressure and base excess before and after MUF. MUF increases systolic blood pressure, haematocrit, arterial oxygen and carbon dioxide tension coming off bypass in paediatric cardiac surgery and reduces heart rate and postoperative fluid overload.

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

CHEST Journal ◽

10.1378/chest.128.3.1291 ◽

2005 ◽

Vol 128 (3) ◽

pp. 1291-1296 ◽

Cited By ~ 48

Author(s):

Oliver Senn ◽

Christian F. Clarenbach ◽

Vladimir Kaplan ◽

Marco Maggiorini ◽

Konrad E. Bloch

Keyword(s):

Carbon Dioxide ◽

Sleep Apnea ◽

Critical Illness ◽

Oxygen Saturation ◽

Arterial Oxygen Saturation ◽

Carbon Dioxide Tension ◽

Arterial Oxygen

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EFFECTS OF SODIUM BICARBONATE BY RAPID INJECTION AND OF OXYGEN IN HIGH CONCENTRATION IN RESPIRATORY DISTRESS SYNDROME OF THE NEWBORN

PEDIATRICS ◽

10.1542/peds.41.6.1063 ◽

1968 ◽

Vol 41 (6) ◽

pp. 1063-1073

Author(s):

George Russell ◽

Ernest K. Cotton

Keyword(s):

Carbon Dioxide ◽

Sodium Bicarbonate ◽

Respiratory Distress Syndrome ◽

Respiratory Distress ◽

Oxygen Tension ◽

Distress Syndrome ◽

Arterial Oxygen Tension ◽

Carbon Dioxide Tension ◽

Arterial Oxygen ◽

Arterial Carbon Dioxide Tension

Following the rapid intravenous injection of sodium bicarbonate in 19 infants suffering from the respiratory distress syndrome of the newborn (RDS), arterial oxygen tension, arterial oxygen saturation and base excess rose, while arterial carbon dioxide tension and hydrogen ion concentration fell. Effective pulmonary blood flow rose, and right-to-left shunting diminished. Following the administration of increased oxygen to 6 infants with less severe RDS, there was a rise in arterial oxygen tension and a fall in arterial carbon dioxide tension. It is suggested that the changes which occur after both forms of therapy are due to a decrease of pulmonary vascular resistance, reduced right-to-left shunt, and improved pulmonary capillary perfusion.

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Successful Transtracheal Lung Ventilation Using a Manual Respiration Valve

Anesthesiology ◽

10.1097/aln.0b013e31817f3de6 ◽

2008 ◽

Vol 109 (2) ◽

pp. 251-259 ◽

Cited By ~ 4

Author(s):

Konrad Meissner ◽

Thomas Iber ◽

Jan-Patrick Roesner ◽

Christian Mutz ◽

Hans-Erich Wagner ◽

...

Keyword(s):

Carbon Dioxide ◽

Arterial Oxygen Tension ◽

Upper Airway ◽

Lung Ventilation ◽

Carbon Dioxide Tension ◽

Arterial Oxygen ◽

Gas Flows ◽

Partial Pressures

Background Lung ventilation through a thin transtracheal cannula may be attempted in patients with laryngeal stenosis or "cannot intubate, cannot ventilate" situations. It may be impossible to achieve sufficient ventilation if the lungs are spontaneously emptying only through the thin transtracheal cannula, which imposes high resistance to airflow, resulting in dangerous hyperinflation. Therefore, the authors describe the use of a manual respiration valve that serves as a bidirectional pump providing not only inflation but also active deflation of the lungs in case of emergency transtracheal lung ventilation. Methods The effectiveness of such a valve was tested in vitro using mechanical lungs in combination with two different cannula sizes and various gas flows. The valve was then tested in five pigs using a transtracheal 16-gauge cannula with three different combinations of inspiratory/expiratory times and gas flows and an occluded upper airway. Results In the mechanical lungs, the valve permitted higher minute volumes compared with spontaneous lung emptying. In vivo, the arterial oxygen and carbon dioxide partial pressures increased initially and then remained stable over 1 h (arterial oxygen tension, 470.8 +/- 86.8; arterial carbon dioxide tension, 63.0 +/- 7.2 mmHg). The inspiratory pressures measured in the trachea remained below 10 cm H2O and did not substantially influence central venous and pulmonary artery pressures. Mean arterial pressure and cardiac output were unaffected by the ventilation maneuvers. Conclusions This study demonstrated in vitro and in vivo in adult pigs that satisfactory lung ventilation can be assured with transtracheal ventilation through a 16-gauge cannula for a prolonged period of time if combined with a bidirectional manual respiration valve.

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Time Course and Pattern of Pulmonary Flow Distribution following Unilateral Airway Occlusion in Sheep

Clinical Science ◽

10.1042/cs0940453 ◽

1998 ◽

Vol 94 (4) ◽

pp. 453-460 ◽

Cited By ~ 8

Author(s):

B. Johansen ◽

M. N. Melsom ◽

T. Flatebø ◽

G. Nicolaysen

Keyword(s):

Carbon Dioxide ◽

Blood Flow ◽

Oxygen Tension ◽

Time Course ◽

Arterial Oxygen Tension ◽

Flow Distribution ◽

Blood Gases ◽

Carbon Dioxide Tension ◽

Arterial Oxygen ◽

Contralateral Lung

1. Unilateral bronchial occlusion causes ipsilateral hypoxic pulmonary vasoconstriction, which shifts blood flow towards the other lung. We studied the time course of flow diversion following acute bronchial occlusion, and the temporal effect of the latter on blood gases and vertical distribution of blood flow within the two lungs. 2. Serial infusions of radioactive or fluorescent microspheres were given to each of seven adult standing sheep before, during occlusion of the left mainstem bronchus for up to 6 min, and after release of occlusion. Pulmonary and systemic arterial pressures were recorded continuously and arterial and mixed venous blood gases were determined intermittently. Post-mortem, the lungs were inflated, dried and cut into slices. Relative blood flow at the time of infusion was expressed as the weight-normalized intensity of each tracer in each slice or lung divided by the weight-normalized intensity in the two lungs. 3. Within 30 s, 1 min and 2 min after onset of occlusion, flow in the occluded lung had decreased to 68–84% (range), 51–78% and 43–79% respectively, of the initial value. In the contralateral lung, flow increased by 10–24%, 14–37% and 23–39% respectively. The distribution of flow along the gravitational axis within each lung varied widely between animals, both before and during occlusion. The during-occlusion profiles in the occluded lung differed from those in the non-occluded lung. In either lung, during-occlusion profiles could not be predicted with certainty from the pre-occlusion profiles. Two minutes post-occlusion, inter- and intra-lung flow distribution were nearly the same as before occlusion. Arterial oxygen tension fell in the first minute of occlusion, but never below 7.5 kPa, and increased slowly thereafter. Arterial carbon dioxide tension increased slightly throughout the occlusion period. No appreciable changes in systemic or pulmonary artery pressure were observed. Post-occlusion, arterial oxygen tension was still sub-normal, while carbon dioxide tension continued to increase. 4. We conclude that acute unilateral bronchial occlusion diverts blood flow within 30 s towards the contralateral lung. This rapidly occurring flow diversion prevents the development of severe arterial hypoxaemia. The variable and largely unpredictable distribution of blood flow in the hyperfused non-occluded lung might explain some of the gas-exchange abnormalities observed in physiologically hyperfused lungs and in patients with one hyperfused lung.

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