Clinical Research Directory

Dexmedetomidine Versus Nitroglycerin on Surgical Field Quality and Drug Cost in Functional Endoscopic Sinus Surgeries

Sinus surgery is one of the most prevalent ear, nose, and throat (ENT) surgeries, which is mainly carried out nowadays through functional endoscopic sinus surgery (FESS) and leads to significant improvement in the clinical symptoms of patients with rhinosinusitis. It is necessary to maintain safe conditions for this surgery, and the major problem reported during FESS under general anesthesia (GA) is impaired visibility due to excessive amount of bleeding. This is particularly important for the successful surgery of the ethmoid and sphenoid sinuses because even minimum amount of bleeding might seriously impair the successful completion of the surgery, increase the operational risk, and increase surgery time which are major concerns for both anesthesiologist and ENT specialist. Controlled hypotension is the commonly used technique to limit blood loss and improve visualization in the surgical field during FESS, various techniques have been adopted to achieve controlled hypotension, one of them is the use of pharmacological drugs in the form of volatile anesthetics, direct-acting vasodilators, autonomic ganglion-blockers, and α-adrenergic receptor blockers. Alpha-2 (α-2) receptors are found in the peripheral and central nervous systems, platelets and many other organs including the liver, pancreas, kidney, and eye. Stimulation of the receptors in the brain and spinal cord inhibits neuronal firing causing hypotension, bradycardia, sedation, and analgesia. Alpha-2 (α-2) agonist drugs have sympatholytic, sedative, anesthetic, and analgesic sparing effects, as well as vasoconstrictive effects and thereby reduce intraoperative bleeding. Also, the use of α-2 agonists in the perioperative period has been associated with reduced anesthetic requirements, decreased heart rate and blood pressure. Dexmedetomidine is a highly selective α-2 adrenergic receptor agonist (selectivity ratio for α2: α1 is 1600:1). The sympatholytic effect of dexmedetomidine made it attractive to be used as a hypotensive drug during surgery because of decreasing heart rate (HR) and cardiac output (CO) without decreasing stroke volume unless the plasma concentrates reaches above 5.1 μg/mL. The cardiovascular effects of dexmedetomidine begin with initial hypertension following the administration of a loading dose, due to the activation of α 2B receptors located on vascular smooth muscle, with subsequent hypotension and bradycardia due to centrally mediated decrease in sympathetic tone. Dexmedetomidine also has sedative, amnesic, anxiolytic, hypnotic, and analgesic effects with minimal changes in respiratory variables. Furthermore, it reduces postoperative nausea, vomiting, and shivering. It also reduces delirium in patients after cardiac surgery. Nitroglycerin is a directly acting vasodilator drug frequently used to produce controlled hypotension because it is easily titratable and having very rapid onset as well as rapid offset of action. However, the disadvantages of nitroglycerin are reflex tachycardia and venous congestion which leads to increased blood loss. Aim of the work was improving surgical field quality and drug cost in patients undergoing Functional Endoscopic Sinus Surgeries by comparing between dexmedetomidine and nitroglycerin.

DDAVP Effect by TEG6 in Cardiac Surgery

Cardiopulmonary bypass (CPB) is a process that uses a pump that temporarily takes over the function of the heart and lungs during cardiac surgery to maintain blood circulation and oxygenation. Using CPB during cardiac surgery can result in complications with blood clotting. Blood clotting is achieved when molecules in the blood, called platelets, are able to form together with the help of other clotting factors to form a clot. A drug called desmopressin (DDAVP) is used to help blood clot properly by increasing the amount of clotting factors in the blood. Several studies have shown that desmopressin has the ability to reduce the amount of blood transfusions needed for cardiac surgery patients in the postoperative period. At LHSC desmopressin is frequently requested by Cardiac Surgeons and Anesthesiologists to stop bleeding and promote blood clotting where required. A test called TEG6s platelet mapping is a blood test used to help manage the use of blood products by being able to provide information on platelet function and blood clotting activity. At the moment, there is a lack of information regarding the use of TEG6s platelet mapping to analyze the effect of desmopressin on blood clotting in cardiac surgery patients after CPB. The purpose of this study is to investigate the dose-related effects of desmopressin on platelet function in patients undergoing cardiac surgery with CPB. By using TEG6s platelet mapping, this study aims to observe dynamic changes in platelet function following desmopressin administration at various time points in the perioperative and postoperative periods.

Ostene in Thoracolumbar Decompression and Fusion Evaluated With VIBE

In spine surgery, it is important to try to minimize bleeding. In particular, spine surgery often involves inserting hardware into bone, and/or removing bone in the spine. Because the bone in the spine contains blood vessels, there can often be bleeding from the bone itself that is difficult to stop completely. One way to stop bone bleeding is through the use of wax-like materials, which plug the bleeding bone and act as a physical barrier to stop bleeding. One example is Ostene bone hemostasis material, which has the advantage of being "water soluble", meaning it will dissolve naturally over time. The purpose of this study is to evaluate how well Ostene does at decreasing bleeding, by using a recognized scale called the validated intraoperative bleeding severity scale, abbreviated as "VIBe". In this study, the investigators will record the bleeding severity throughout multiple time points in surgery using this scale, and then the investigators will compare the measurements to patients in the past who did not receive Ostene. Overall, this research will help measure how well Ostene decreases bleeding.

Lidocaine and Dexmedetomidine Infusions for Intraoperative Bleeding in Functional Endoscopic Sinus Surgery

This work aims to compare lidocaine and dexmedetomidine infusions for intraoperative bleeding in patients undergoing functional endoscopic sinus surgery.

The Effect of Adding Either Propofol or Ketamine to Magnesium and Lidocaine Infusions in Nasal Surgeries.

Nasal surgeries are common day case procedures. Although surgical complications are rare, bleeding decreases surgical field visibility and may cause vascular, orbital or intracranial complications in addition to failure of procedure. So, it is crucial to maintain hypotensive anaesthesia to optimize the surgical field.

Measurement of Blood Loss in Adenotonsillectomy During General Anesthesia According to the Application of Nondepolarizing Muscle Relaxants

Although tonsillectomy is one of the most commonly performed surgeries, a review of literature reveals no articles dealing with the study of intraoperative blood loss in tonsillectomy and adenotonsillectomy according to the use of nondepolarizing muscle relaxants. The primary aim of our trial will be to compare blood loss in the operating theatre and postoperatively in two groups of children having adenotonsillectomy. The trial numbers will be randomised in blocks.