The effects of bolus compared to continuous administration of adrenaline on cerebral oxygenation during experimental cardiopulmonary resuscitation.

Background: Bolus administration of adrenaline during cardiopulmonary resuscitation (CPR) results in only short-term increases in systemic and cerebral perfusion pressure (CePP) with unclear effects on cerebral oxygenation. The aim of this study was to investigate the effects of bolus compared to continuous adrenaline administration on cerebral oxygenation in a porcine CPR model. Methods: After five minutes of cardiac arrest, mechanical CPR was performed for 15 min. Adrenaline (45 µg/kg) was administered either as a bolus every five minutes or continuously over the same period via an infusion pump. Main outcome parameter was brain tissue oxygen tension (PbtO2), secondary outcome parameters included mean arterial pressure (MAP), intracranial pressure (ICP), CePP and cerebral regional oxygen saturation (rSO2) as well as arterial and cerebral venous blood gases. Results: During CPR, mean MAP (45 ± 8 mmHg vs. 38 ± 8 mmHg; p = 0.0827), mean ICP (27 ± 7 mmHg vs. 20 ± 7 mmHg; p = 0.0653) and mean CePP (18 ± 8 mmHg vs. 18 ± 8 mmHg; p = 0.9008) were similar in the bolus and the continuous adrenaline group. Also, rSO2 (both 24 ± 6 mmHg; p = 0.9903) and cerebral venous oxygen saturation (18 ± 12% versus 27.5 ± 12%; p = 0.1596) did not differ. In contrast, relative PbtO2 reached higher values in the continuous group after five minutes of CPR and remained significantly higher than in the bolus group until the end of resuscitation. Conclusion: Continuous administration of adrenaline improved brain tissue oxygen tension compared with bolus administration during prolonged CPR.

Adrenaline improves regional cerebral blood flow, cerebral oxygenation and cerebral metabolism during CPR in a porcine cardiac arrest model using low-flow extracorporeal support.

BACKGROUND: The effects of adrenaline on cerebral blood vessels during cardiopulmonary resuscitation (CPR) are not well understood. We developed an extracorporeal CPR model that maintains constant low systemic blood flow while allowing adrenaline-associated effects on cerebral vasculature to be assessed at different mean arterial pressure (MAP) levels independently of the effects on systemic blood flow. METHODS: After eight minutes of cardiac arrest, low-flow extracorporeal life support (ECLS) (30 ml/kg/min) was started in fourteen pigs. After ten minutes, continuous adrenaline administration was started to achieve MAP values of 40 (n = 7) or 60 mmHg (n = 7). Measurements included intracranial pressure (ICP), cerebral perfusion pressure (CePP), laser-Doppler-derived regional cerebral blood flow (CBF), cerebral regional oxygen saturation (rSO2), brain tissue oxygen tension (PbtO2) and extracellular cerebral metabolites assessed by cerebral microdialysis. RESULTS: During ECLS without adrenaline, regional CBF increased by only 5% (25th to 75th percentile: -3 to 14; p = 0.2642) and PbtO2 by 6% (0-15; p = 0.0073) despite a significant increase in MAP to 28 mmHg (25-30; p < 0.0001) and CePP to 10 mmHg (8-13; p < 0.0001). Accordingly, cerebral microdialysis parameters showed a profound hypoxic-ischemic pattern. Adrenaline administration significantly improved regional CBF to 29 ± 14% (p = 0.0098) and 61 ± 25% (p < 0.001) and PbtO2 to 15 ± 11% and 130 ± 82% (both p < 0.001) of baseline in the MAP 40 mmHg and MAP 60 mmHg groups, respectively. Importantly, MAP of 60 mmHg was associated with metabolic improvement. CONCLUSION: This study shows that adrenaline administration during constant low systemic blood flow increases CePP, regional CBF, cerebral oxygenation and cerebral metabolism.

SARS-COV-2 infection in the perioperative of pulmonary lobectomy. About a case.

OBJECTIVE: To describe the form of severe clinical presentation of SARS-COV-2 infection in the early phase, also the timely treatment of COVID-19 pneumonia in postoperative pulmonary lobectomy. METHOD: Case report where the data were extracted from the clinical history and is in accordance with the SCARE 2018 criteria. DESCRIPTION OF THE CASE: A 36-year-old man, with no significant history, who presented fever and mucopurulent expectoration of 1 month of evolution, received antibiotics for 4 weeks without response to treatment. Chest tomography shows cystic image with heterogeneous content in the left lower lobe. We decided to opt for surgery, previously 1 PCR in RT and 7 serological tests for COVID-19 were performed, the result of which was non-reactive. In the postoperative period, the patient developed fever and dyspnea on mild exertion, so a new serological test for COVID-19 was performed: IgM/IgG reactive, in addition chest tomography showed both lungs with "cracy paving" pattern. DISCUSSION: The serological tests did not contribute to a timely diagnosis of COVID-19 and generated confusion. We used oxygen therapy, broad spectrum antibiotics since the diagnosis of COVID-19. Likewise, respiratory physiotherapy was intensified even after discharge. CONCLUSION: The early diagnosis and use of antibiotics at doses of sepsis, associated with corticosteroid pulses and respiratory physiotherapy improve COVID-19 pneumonia in postoperative lung surgery.

Effects of different adrenaline doses on cerebral oxygenation and cerebral metabolism during cardiopulmonary resuscitation in pigs.

BACKGROUND: The influence of adrenaline during cardiopulmonary resuscitation (CPR) on the neurological outcome of cardiac arrest survivors is unclear. As little is known about the pathophysiological effects of adrenaline on cerebral oxygen delivery and cerebral metabolism we investigated its effects on parameters of cerebral oxygenation and cerebral metabolism in a pig model of CPR. METHODS: Fourteen pigs were anesthetized, intubated and instrumented. After 5 min of cardiac arrest CPR was started and continued for 15 min. Animals were randomized to receive bolus injections of either 15 or 30 µg/kg adrenaline every 5 min after commencement of CPR. RESULTS: Measurements included mean arterial pressure (MAP), intracranial pressure (ICP), cerebral perfusion pressure (CPP), cerebral regional oxygen saturation (rSO2), brain tissue oxygen tension (PbtO2), arterial and cerebral venous blood gases and cerebral microdialysis parameters, e.g. lactate/pyruvate ratio. Adrenaline induced a significant increase in MAP and CPP in all pigs. However, increases in MAP and CPP were short-lasting and tended to decrease with repetitive bolus administration. There was no statistical difference in any parameter of cerebral oxygenation or metabolism between study groups. CONCLUSIONS: Both adrenaline doses resulted in short-lasting CPP peaks which did not translate into improved cerebral tissue oxygen tension and metabolism. Further studies are needed to determine whether other dosing regimens targeting a sustained increase in CPP, may lead to improved brain oxygenation and metabolism, thereby improving neurological outcome of cardiac arrest patients.

Pulse Oximeter Saturation Targeting and Oximeter Changes in the Benefits of Oxygen Saturation Targeting (BOOST)-II Australia and BOOST-II UK Oxygen Trials.

Infants in the Australian and UK Benefits of Oxygen Saturation Targeting-II trials treated using revised oximeters spent more time within their planned pulse oximeter saturation target ranges than infants treated using the original oximeters (P < .001). This may explain the larger mortality difference seen with revised oximeters. If so, average treatment effects from the Neonatal Oxygen Prospective Meta-analysis trials may be underestimates.

Effects of head-up vs. supine CPR on cerebral oxygenation and cerebral metabolism - a prospective, randomized porcine study.

BACKGROUND: Recent studies have shown that during cardiopulmonary resuscitation (CPR) head-up position (HUP) as compared to standard supine position (SUP) decreases intracranial pressure (ICP) and increases cerebral perfusion pressure (CPP). The impact of this manoeuvre on brain oxygenation and metabolism is not clear. We therefore investigated HUP as compared to SUP during basic life support (BLS) CPR for their effect on brain oxygenation and metabolism. METHODS: Twenty pigs were anaesthetized and instrumented. After 8 min of cardiac arrest (CA) pigs were randomized to either HUP or SUP and resuscitated mechanically for 20 min. Mean arterial pressure (MAP), ICP, CPP, cerebral regional oxygen saturation (rSO2) and brain tissue oxygen tension (PbtO2) were measured at baseline, after CA and every 5 min during CPR. Cerebral venous oxygen saturation (ScvO2) was measured at baseline, after CA and after 20 min of CPR. Cerebral microdialysis parameters, e.g. lactate/pyruvate ratio (L/P ratio) were taken at baseline and the end of the experiment. RESULTS: ICP was significantly lower in HUP compared to SUP animals after 5 min (18.0 ±â€¯4.5 vs. 24.1 ±â€¯5.2 mmHg; p = 0.033) and 20 min (12.0 ±â€¯3.4 vs. 17.8 ±â€¯4.3 mmHg; p = 0.023) of CPR. Accordingly, CPP was significantly higher in the HUP group after 5 min (11.2 ±â€¯9.5 vs. 1.0 ±â€¯9.2 mmHg; p = 0.045) and 20 min (3.4 ±â€¯6.4 vs. -3.8 ±â€¯2.8 mmHg; p = 0.023) of CPR. However, no difference was found in rSO2, PbtO2, ScvO2 and L/P ratio between groups after 20 min of CPR. CONCLUSION: In this animal model of BLS CPR, HUP as compared to SUP did not improve cerebral oxygenation or metabolism.

Platypnea-Orthodeoxia Syndrome: To Shunt or Not to Shunt, That is the Question.

Platypnea-orthodeoxia syndrome is a rare disease defined by dyspnea and deoxygenation, induced by an upright position, and relieved by recumbency. Causes include shunting through a patent foramen ovale and pulmonary arteriovenous malformations. A 79-year-old woman experienced 2 syncopal episodes at rest and presented at another hospital. In the emergency department, she was hypoxic, needing 6 L/min of oxygen. Her chest radiograph showed nothing unusual. Transthoracic echocardiograms with saline microcavitation evaluation were mildly positive early after agitated-saline administration, suggesting intracardiac shunting. She was then transferred to our center. Right-sided heart catheterization revealed no oximetric evidence of intracardiac shunting while the patient was supine and had a low right atrial pressure. However, her oxygen saturation dropped to 78% when she sat up. Repeat transthoracic echocardiography while sitting revealed a dramatically positive early saline microcavitation-uptake into the left side of the heart. Transesophageal echocardiograms showed a patent foramen ovale, with right-to-left shunting highly dependent upon body position. The patient underwent successful percutaneous patent foramen ovale closure, and her oxygen supplementation was suspended. In patients with unexplained or transient hypoxemia in which a cardiac cause is suspected, it is important to evaluate shunting in both the recumbent and upright positions. In this syndrome, elevated right atrial pressure is not necessary for significant right-to-left shunting. Percutaneous closure, if feasible, is first-line therapy in these patients.

Acute Hypoxic Test in Patients with Prediabetes.

Shatylo, Valerii B., Tetiana V. Serebrovska, Anna V. Gavalko, Egor Egorov, and Oleg V. Korkushko. Acute hypoxic test in patients with prediabetes. High Alt Med Biol. 17:101-107, 2016.-Prediabetes is a state of impaired carbohydrate metabolism when not all of the symptoms required to label a person as diabetic are present, but blood glucose is higher than in healthy subjects. Recent evidence suggests that intermittent hypoxia training (IHT) might provide a cost-effective strategy for improving metabolic functioning. One of the most important aspects of the successful IHT application is individualized approach to hypoxic dose and regimen prescription. To establish the relationships between indices of carbohydrate metabolism and individual resistance to hypoxia, the acute hypoxic test (AHT, breathing gas mixture with 12% O2 during 20 minutes) was performed in 33 healthy volunteers (mean age, 63.0, range, 44-76; fasting plasma glucose (FPG) less than 5.6 mmol/L and 2 hours postoral glucose tolerance test (OGTT) glycemia less than 7.8 mmol/L) and 30 patients with impaired glucose metabolism (mean age, 65.5, range, 44-75; FPG from 5.6 to 6.9 mmol/L and 2 hours post-OGTT glycemia from 7.8 to 11 mmol/L). Negative correlation was found between the SaO2 level at 20th minute AHT and FPG (r = -0.83; p < 0.01) and insulin (r = -0.27; p < 0.05), as well as 2 hours post-OGTT glucose and insulin levels (r = -0.75 and -0.40, respectively). Longer recovery time and less effective functioning of respiratory and cardiovascular systems were also registered in patients with prediabetes showing that their cardiovascular resilience is impaired compared to normoglycemic controls. These patterns of relationship must be considered when assigning the individual modes of IHT.

Platypnea-Orthodeoxia Syndrome: Diagnostic Challenge and the Importance of Heightened Clinical Suspicion.

Platypnea-orthodeoxia syndrome is an uncommon condition of positional dyspnea and hypoxemia; symptoms occur when the patient is upright and resolve with recumbency. Causes can be broadly categorized into 4 groups: intracardiac shunting, pulmonary shunting, ventilation-perfusion mismatch, or a combination of these. Platypnea-orthodeoxia syndrome should be suspected when normal arterial oxygen saturations are recorded while an individual is supine, followed by abrupt declines in those saturations when upright. Further investigations with use of imaging and cardiac catheterization aid in the evaluation. When platypnea-orthodeoxia syndrome is due to intracardiac shunting without pulmonary hypertension, intracardiac shunt closure can be curative. In this article, we report a case of platypnea-orthodeoxia syndrome in an 83-year-old woman who was successfully treated by means of percutaneous transcatheter closure of an atrial septal defect.

Cerebral, renal and mesenteric regional oxygen saturation of term infants during transition.

OBJECTIVE: To measure cerebral regional oxygen saturation (CrSO2), renal regional oxygenation saturation (RrSO2) and mesenteric tissue regional oxygen saturation (MrSO2) during immediate transition and continuously for the first 9 hours of age. Fractional tissue oxygen extraction of the brain (CtFOE), kidneys (RtFOE), splanchnic tissue (MtFOE) were also assessed. STUDY DESIGN: Prospective, observational study of 61 term infants, delivered by elective caesarean section. Using near-infrared spectroscopy, changes in CrSO2, RrSO2, MrSO2 and changes in CtFOE, RtFOE and MtFOE were measured all through the first 9 hours of life. All the episodes of feeding during this period were recorded. RESULTS: Mean CrSO2 increased quickly to 7 minutes, with no further changes. On the other hand, mean RrSO2 and mean MrSO2 increased for 10 minutes and thereafter they remained on their newly reached level. RrSO2 and MrSO2 were significantly lower at 3-4-5-6-7 minutes of life compared to the CrSO2 (p<0.05). RtFOE and MtFOE were significantly higher at 3-4-5-6-7 minutes of life compared to the CtFOE (p<0.05). During feeding, CrSO2, RrSO2 and MrSO2 did not significantly change. CONCLUSIONS: During early adaptive period, oxygen delivery is preserved to 'vital' organs, like brain, at the expense of kidneys and splanchnic tissue. Term infants can provide for the increasing metabolic activity of the intestinal tract during feeding periods without compromising oxygenation.

Isolated right superior vena cava drainage into the left atrium diagnosed noninvasively in the peripartum period.

Isolated right superior vena cava drainage into the left atrium is an extremely rare cardiac anomaly, especially in the absence of other cardiac abnormalities. Only 28 of 5,127 reported consecutive congenital cardiac cases involved superior vena cava drainage into the left atrium, and all were associated with other cardiac anomalies. Of 19 reported cases of right superior vena cava drainage into the left atrium, most patients have been children who were experiencing mild hypoxemia and cyanosis. Herein, we describe the case of a 34-year-old woman who presented with asymptomatic hypoxemia in the peripartum period. She was diagnosed to have isolated drainage of the right superior vena cava into the left atrium. To the best of our knowledge, this is the 1st reported instance of such diagnosis by use of noninvasive imaging only, without cardiac catheterization. We also review the medical literature that pertains to our patient's anomaly.

Methemoglobinemia in a young man.

In patients who have cyanosis and dyspnea that are unrelated to a cardiopulmonary cause, 1 rare possible diagnosis is methemoglobinemia. This condition is generally asymptomatic, even when the methemoglobin level is as high as 40% of the total hemoglobin value. In the patient described herein, extensive pulmonologic and cardiologic investigations failed to yield the correct diagnosis, which was finally made on the basis of physical findings and arterial blood-gas analysis. Later, a DNA analysis, reported separately by others, showed that the patient's methemoglobinemia was caused by a novel mutation of the cytochrome b5 reductase gene.

Mesenteric oxygen desaturation in an infant with congenital heart disease and necrotizing enterocolitis.

Congenital heart disease is a risk factor for the development of necrotizing enterocolitis, although the exact mechanism of development remains unclear. Herein, we report the case of an infant with pulmonary atresia, an intact ventricular septum, and multiple aortopulmonary collateral vessels. At 4 weeks of age, the infant developed necrotizing enterocolitis in association with significant mesenteric oxygen desaturation, as measured by means of near-infrared spectroscopy. With bowel rest and antibiotic therapy, the patient's mesenteric oxygen saturation and clinical status improved. This case highlights the importance of impaired mesenteric oxygen delivery consequential to congenital heart disease as a possible risk factor for necrotizing enterocolitis, and the use of near-infrared spectroscopy to measure tissue perfusion noninvasively in high-risk patients. To our knowledge, this is the 1st report of mesenteric oxyhemoglobin desaturation in association with necrotizing enterocolitis in a patient who also had congenital heart disease.