Accuracy of Oximeters With Hypoxia and Methemoglobin or Carboxyhemoglobin
Healthy VolunteersAccuracy of the oximeter.
Postoperative Residual Curarisation at Arrival in the Post-anesthesia Care Unit
Postoperative Residual CurarisationPostoperative Hypoxemia1 moreSeveral studies have documented that neuromuscular block often persists in the postanesthesia care unit (PACU). Residual paralysis is associated with postoperative complications such as hypoxia, weakness, and respiratory failure. The data in the current literature on residual paralysis in the PACU were almost exclusively obtained with acetylcholinesterase inhibitors as they were the only reversal agents available prior to the introduction in clinical practice of sugammadex (Bridion®) in the European Union and in some other countries, except for the USA. Reassessment of practice in this regard is relevant, now that sugammadex (Bridion®) has become available in our country since 2009. This study is an observational/non-interventional, non-randomized study involving adult patients undergoing different types of elective surgical procedures requiring general anesthesia with neuromuscular blocking drugs (NMBDs). Administration of NMBDs and reversal agents (as well as all drugs which will be used during anesthesia) will be performed in accordance with routine anesthetic practice. The study population will comprise about 600 surgical patients. Immediately after the patients' arrival in the PACU, a study nurse will record the acceleromyographic responses of their adductor pollicis muscle as percent of the train-of-four (TOF%) on stimulation of the ulnar nerve. A TOF of 90% will be used as cut-off value to exclude residual paralysis. Pulse oximetry (SpO2) will be measured continuously throughout the PACU admission, and SpO2 values will be recorded at 1-min intervals for the first 30 min. PACU nurses caring for the patient will document the occurrence of any of the following events during the first 30 min of PACU admission: the number of episodes of hypoxemia (SpO2<90%), the lowest SpO2 observed by nursing staff, the requirement for either tactile or verbal stimulation to maintain SpO2 greater than 90%, and any clinical evidence of airway obstruction. The primary objective is to evaluate the incidence of postoperative residual curarisation at PACU arrival in patients reversed with sugammadex (Bridion®), neostigmine and in case of spontaneous recovery. The secondary objectives are to evaluate: Oxygen saturation (SpO2) at PACU arrival Possible episodes of SpO2 <90% in the PACU Airway maneuvers and/or stimulation required to maintain SpO2 >90% in the PACU Need for re-intubation.
Umbilical Cord Blood Proteomic Analysis and Neonatal Brain Injury
Hypoxia-IschemiaBrain1 moreThe investigators propose to compare the proteomic analysis of umbilical venous blood from neonates with brain injury to gestational age matched noninjured controls. After delivery an umbilical arterial gas and a 10 ml umbilical venous sample are obtained, then the remainder of the cord blood is discarded. The investigators plan to use this cord blood that would otherwise be discarded to perform our proteomic analysis. The investigators will use up to 20 ml of cord blood per delivery. This will be a 5 year study during which time the investigators hope to analyze 450 infants at Johns Hopkins Hospital and Bayview Medical Center. The investigators will obtain an umbilical venous sample from infants born at < 34 weeks gestation. For infants born at > 34 weeks the investigators will obtain an umbilical venous sample for any infant suspected to be at risk for neurologic injury by having a diagnosis of chorioamnionitis during labor, nonreassuring fetal heart rate tracing at the time of delivery, or a 5 minute Apgar < 7. For the infants born at < 34 weeks the brain injured infants will be compared to gestational age matched controls without brain injury. For the infants born at > 34 weeks, each infant later confirmed to have neurologic morbidity will be compared to a gestational age matched noninjured control. The investigators hope to use proteomic analysis to determine if there are measurable differences in protein expression between the 2 groups.
Different Preoxygenation Methods In Cesarean Section
HypoxiaHyperoxiaThe study aimed to evaluate different preoxygenation methods (tidal volume for 3 minutes and 4 deep breaths) in pregnant women with oxygen reserve index (ORI). After the routine monitoring of healthy ASA II pregnant patients between the ages of 18-45, different preoxygenation methods will be applied, and the oxygen status of the patients will be compared with ORI monitoring.
Developmental Outcomes
Hypoxic-Ischemic EncephalopathyDetermine whether the concentrations of UCH-L1 and GFAP measured in umbilical cord blood and in blood 0-6 hours postnatal accurately predict the extent of neurodevelopmental deficits and/or death at 18-20 months.
Functional MRI of Hypoxia-mediated Rectal Cancer Aggressiveness
Rectal DiseasesRectal Neoplasms2 moreThe purpose of this study is to establish a reliable method for detection of rectal cancer patients with aggressive tumor at risk of metastatic disease and death by functional MRI.
Effect of Volume and Type of Fluid on Postoperative Incidence of Respiratory Complications and Outcome...
Respiratory FailureAcute Respiratory Failure Requiring Reintubation4 moreIntraoperative intravenous fluid management practice varies greatly between anesthesiologists. Postoperative fluid based weight gain is associated with major morbidity. Postoperative respiratory complications are associated with increased morbidity, mortality and hospital costs. The literature shows conflicting data regarding intraoperative fluid resuscitation volume. No large-scale studies have focused on intraoperative fluid management and postoperative respiratory dysfunction. Hypotheses: Primary - Liberal intraoperative fluid resuscitation is associated with an increased risk of 30 day mortality Secondary - Liberal intraoperative fluid resuscitation is associated with increased likelihood of postoperative respiratory failure, pulmonary edema, reintubation, atelectasis, acute kidney injury and peri-extubation oxygen desaturation.
Obstructive Sleep Apnoea and Adipose Tissue Dysfunction
Obstructive Sleep ApnoeaObesity1 moreDysfunctional adipose tissue predisposes to cardiovascular disease. Similarly, the risk of cardiovascular disease appears to be increased in subjects with obstructive sleep apnoea. Reduced adipose tissue oxygen availability has been described in obesity and may also be a mechanism in obstructive sleep apnoea. Hypoxia induces inflammation and fibrosis in adipose tissue which are factors contributing to cardiovascular risk. The investigators hypothesize that adipose tissue's oxygen uptake is reduced in subjects with obstructive sleep apnoea by comparing in vivo AT oxygenation and blood flow in tissue of control subjects.
Infant Pulse Oximetry in Pakistan Study
HypoxemiaNeonatal Sepsis1 moreHypoxemia is an abnormally low concentration of oxygen in the blood, and is an important sign of cardio-respiratory compromise in acutely ill patients. Pulse oximetry (PO) is a rapid, portable, non-invasive and accurate method of measuring arterial hemoglobin oxygenation (Sp02), and can therefore be readily implemented to detect hypoxemia in the clinical setting. In this research study, we propose to test the hypothesis that the use of pulse oximetry to detect hypoxemia by first-level health workers' in Karachi, Pakistan is useful and feasible for the identification of the infants most urgently in need of medical care. We will enroll 1,400 infants 0-59 days of age who present to one of two primary health centers in Karachi. Infants will undergo brief clinical assessment by a community health worker (CHW) based on the WHO/UNICEF Integrated Management of Neonatal and Child Illness (IMNCI) algorithm, assessment by two pulse oximetry devices, and examination by a physician. The primary outcomes include prevalence of hypoxemia, feasibility of PO (e.g., time to obtain measurement, number of infants for who repeat measurements are required), and concordance between paired measurements on separate devices.
Effects of O2 and/or CO2 Inhalation on Rest and Exercise Pulmonary Hemodynamic
Pulmonary Vascular Sensibility in HypoxiaHypercapnia1 moreThe aim of this study is to describe the pulmonary hemodynamic evolution at rest and during a short constant load exercise in 4 conditions : normoxia hypoxia hypercapnia association hypoxia and hypercapnia