Effect of Hypotensive Anesthesia on the Perfusion Index
Controlled Hypotension for Nasal SurgeriesControlled hypotension has been used as a mean of reducing intraoperative blood loss and better visualization of the surgical field in nasal surgeries. Perfusion index has been considered a useful tool for monitoring changes in peripheral perfusion using Masimo set and serum lactate for central perfusion. Many medications were used to induce hypotension. In this study we will compare the effects of tridil and labetalol on the perfusion.
Evaluation of the ORTHO-LBNP System
Orthostatic HypotensionIschemia1 moreThe pilot study aims to evaluate a prototype system that enables military pilots to train under conditions of orthostatic hypotension and ischemic hypoxia. Both of these phenomena are experienced by aircraft crews of mainly highly maneuverable aircraft, and their syndromes include loss of color vision, loss of peripheral vision, blackout and finally G-induced loss of consciousness (G-LOC). A motorized tilt table to generate orthostatic (ORTHO) stress combined with an automatically controlled lower body negative pressure (LBNP) chamber to extort pooling of blood in the lower extremities has been developed in order to obtain new knowledge on counteracting the above-mentioned effects and minimizing the risk of their occurrence. This will help optimize the selection procedures of candidates with the best physiological predispositions to work as military pilots. The system is equipped with modules for monitoring biomedical parameters of a subject, including cerebral oxygenation, which ensures their safety and provides a source of data for performing advanced analyses. The ORTHO-LBNP system has been subjected to comprehensive laboratory tests and after a successful testing is ready for a pilot study involving pilots and/or cadets of the Polish Air Force Academy (PAFA). It is anticipated that new indicators will be proposed to enable an objective assessment of the predispositions to pursue a military pilot career. The prototype system can be easily adaptable to the needs of clinical and sports medicine as well as rehabilitation.
Fractional Spinal Anesthesia and Systemic Hemodynamics in Frail Elderly Hip Fracture Patients.
Hip FracturesAnesthesia3 moreAging and frailty make the elderly patients susceptible to hypotension following spinal anaesthesia. The systemic haemodynamic effects of spinal anaesthesia are not well known. In this study, we examine the systemic haemodynamic effects of fractional spinal anaesthesia following intermittent microdosing of a local anesthetic and an opioid. We included 15 patients aged over 65 with considerable comorbidities, planned for emergency hip fracture repair. Patients received a spinal catheter and cardiac output monitoring using the LiDCOplus system. Invasive mean arterial pressure (MAP), cardiac index, systemic vascular resistance index, heart rate and stroke volume index were registered. Two doses of bupivacaine 2,25 mg and fentanyl 15µg were administered with 25 minutes in between. Hypotension was defined as a fall in MAP by >30% or a MAP <65 mmHg
Remifentanil and Nitroprusside for Controlled Hypotension
HypotensionControlledThe purpose of this study is the comparison of the cardiovascular effects of remifentanil and nitroprusside for controlled hypotension
Safety Study of Two Regimen for Sedation for Transesophageal Echocardiography
HypotensionThe purpose of this study is to determine whether sedation with a combination of pethidin hydrochlorid plus midazolam intravenously (i.v.) is superior to propofol i.v. alone in relation to blood pressure drops during an transesophageal echocardiographic examination (TEE).
Studying the Effect of Dialysate Temperature on Toxin Removal and Hypotension
Dialysis AmyloidosisHypotensionHemodialysis (HD) is widely used treatment for end stage renal diseases (ESRD) patients. The chief aims of HD are solute and fluid removal. Decades of practice have improved HD care, but more can be done to improve morbidity and mortality. Enhancing toxin removal is an important consideration for improved patient outcomes. Also, decreasing the incidence of intra-dialytic hypotensive (IDH) episodes (dominant in Singapore patient cohort) can significantly reduce associated morbidities and mortality. A simple maneuver for clinicians is the dialysate temperature. Literature suggests that a lower dialysate temperature (35ºC) results in reduced hypotensive episodes by vasoconstriction. Conversely, higher dialysate temperature resulting in higher blood temperature decreases the peripheral resistance, leading to increased toxin removal, but may cause IDH episodes partly due to vasodilation. Optimal manipulation of the dialysate temperature is therefore primary handles to obtain the improved patient outcomes. In this study, the effect of dialysate temperature (cool vs. warm dialysate) on toxin removal will be studied. In both the interventions, outcome measure will be patient hemodynamic response and amount of toxins removed. The spent dialysate will be collected to study the quantum of toxin removed.
Effect of Levodopa on Cardiovascular Autonomic Function in Parkinson's Disease
Parkinson DiseaseOrthostatic HypotensionLevodopa is a precursor of dopamine and is the treatment of choice to treat the motor symptoms of Parkinson's disease (PD); however, the effect of levodopa on cardiovascular autonomic function in PD is poorly understood. Orthostatic hypotension has been documented as a potential side effect of levodopa. As a result, clinicians may be reluctant to prescribe levodopa in patients with PD with neurogenic orthostatic hypotension (PD+OH), which leads to suboptimal management of motor symptoms. On the other hand, other studies failed to show any clear relationship between levodopa and orthostatic hypotension in patients with PD. Important limitations of prior studies include the lack of detailed investigation of baroreflex cardiovagal and sympathetic noradrenergic functions and the fact that the same patients were not tested on and off levodopa. The investigators propose to investigate the effects of levodopa on cardiovascular autonomic function in patients with PD+OH and PD without neurogenic orthostatic hypotension (PD-OH) by performing standardized autonomic testing in the same patients on and off levodopa.
Use of Capnography in EGD and Colonoscopy With Moderate Sedation.
HypoxiaApnea2 moreThis study will provide capnography monitoring during routine upper endoscopy and colonoscopy with moderate sedation in order to see if it improves safety.
Influence of Injection Rate of Intrathecal Mixture of Local Anesthesia on Hypotension in Cesarean...
HypotensionHypotension is the most common complication of neuraxial anesthesia in obstetric patients and its prevalence in cesarean section is about 50-90%. Maternal hypotension causes unpleasant symptoms such as nausea, vomiting, loss of consciousness, respiratory depression, and cardiac arrest. Hypotension may reduce placental perfusion and result in fetal acidosis and neurological injury. Several techniques have been proposed to prevent hypotension. The recommended spinal block height to ensure patient comfort for Cesarean delivery is T4-6. Clinically, it is desirable that the spread of local anesthetic through the cerebrospinal fluid (CSF) achieves a sensory level no higher than the T4 dermatome to avoid extensive sympathetic block. It is also important that the spinal block level be no lower than T6 to avoid patient discomfort during peritoneal manipulation and uterine exteriorization. The effect of injection speed on spread of spinal anesthesia is controversial. Several studies have demonstrated more extensive spread with faster injection while others report either greater spread with slower injection, or no difference. Slow injection of hyperbaric bupivacaine 10 mg over 60 and 120 sec has been shown to reduce the incidence and severity of hypotension during Cesarean delivery under spinal anesthesia.
The Effects of Dietary Salt on Post-exercise Hypotension
Blood PressurePost-Exercise HypotensionThe new American Heart Association (AHA) blood pressure guidelines are expected to raise the prevalence of high blood pressure to ~46% in the United States. One recommendation for lowering blood pressure is aerobic exercise, which produces a period of lowered blood pressure (post-exercise hypotension; PEH) that lasts up to 24 hours. It is believed that PEH may be responsible for the observations of lowered blood pressure following initiation of exercise. However, most Americans eat too much salt, which expands plasma volume and may prevent PEH, rending aerobic exercise ineffective in improving blood pressure status.