Anesthesia, Spinal

The duration of sensory and motor block after spinal anaesthesia varies widely between patients given the same dose of local anaesthetic. Much of this variability is explained by differences in lumbosacral cerebrospinal fluid volume, which cannot be measured routinely in clinical practice but is related to simple body measurements such as abdominal circumference and vertebral column length. This prospective observational study will develop and internally validate prediction models for the duration of sensory and motor block following spinal anaesthesia in adults undergoing elective surgery. Preoperative clinical and anthropometric variables will be recorded, and block regression will be assessed serially after intrathecal injection. Machine learning methods (lasso regression, ridge regression, random forest, extreme gradient boosting, and support vector regression) will be developed and compared against multivariable linear regression as the reference model. The aim is a practical tool that helps anaesthetists anticipate how long a spinal block will last in an individual patient, supporting decisions about case scheduling, supplementation, and discharge planning.

This prospective observational study aims to investigate the role of the baseline perfusion index (PI) in predicting spinal anesthesia-induced hypotension (SAIH) in ASA I-II patients undergoing day-case knee arthroscopy. Spinal anesthesia is a widely preferred technique for lower extremity surgeries, including knee arthroscopy. However, sympathetic blockade during spinal anesthesia frequently leads to significant hemodynamic instability, particularly hypotension, which can result in adverse perioperative outcomes. While age and baseline blood pressure are traditional risk factors, they often fail to accurately predict the onset of hypotension in healthy populations. The perfusion index (PI), a non-invasive parameter measured via pulse oximetry, reflects peripheral vascular tone and baseline sympathetic activity. An elevated baseline PI indicates baseline vasodilation and a higher susceptibility to sympathectomy, potentially offering an early and non-invasive prediction of SAIH before the hemodynamic collapse occurs. The primary outcome of the study is the incidence of spinal anesthesia-induced hypotension (defined as a mean arterial pressure \< 65 mmHg or a decrease in systolic blood pressure \> 25% from baseline). Secondary outcomes include the onset time of sensory block, and intraoperative ephedrine and fluid requirements.

The goal of this randomized controlled trial is to determine whether low-dose hyperbaric bupivacaine provides better hemodynamic stability and postoperative recovery compared with standard-dose hyperbaric bupivacaine in elderly patients undergoing lower limb orthopedic surgery under spinal anesthesia. The main questions it aims to answer are: * Does low-dose hyperbaric bupivacaine reduce the incidence of intraoperative hypotension and bradycardia compared with standard-dose hyperbaric bupivacaine? * Does low-dose hyperbaric bupivacaine improve postoperative recovery profile compared with standard-dose hyperbaric bupivacaine? Researchers will compare elderly patients receiving low-dose hyperbaric bupivacaine with those receiving standard-dose hyperbaric bupivacaine to determine whether a lower intrathecal dose improves cardiovascular stability and recovery without compromising the effectiveness of spinal anesthesia. Participants will: * Provide written informed consent before enrollment. * Undergo elective lower limb orthopedic surgery under spinal anesthesia. * Be randomly assigned to receive either low-dose or standard-dose hyperbaric bupivacaine. * Have their blood pressure, heart rate, and other vital signs monitored throughout the surgical procedure. * Be assessed for intraoperative hypotension and bradycardia according to predefined study criteria. * Be evaluated for postoperative recovery parameters, including motor recovery and readiness for postoperative recovery and mobilization. The information obtained from this study may help identify a safer and more effective spinal anesthetic technique for elderly patients undergoing orthopedic surgery.

Pain management after total hip replacement is one of the most important aspects of postoperative care for patients and clinicians alike. One of the most common techniques used in anesthesia for this procedure is spinal anesthesia with concurrent administration of opioids into spinal sac. Addition of opioids not only prolongs the anesthesia but also provides pain relief after the procedure for a limited amount of time. Because of its unique chemical properties morphine provides the longest pain relief amongst currently known opioids lasting up to 24 hours. Unfortunately this beneficial effect is associated with both minor and serious adverse effects, most important of which is respiratory depression. To limit this potenitialy fatal adverse effect dosing of morphine must be very precise in order to balance advantages and risks. The aim of the study was to assess effectiveness and safety profile of different doses of morphine administered during spinal anesthesia for pain control.

This research project aims to identify a safer method of spinal anaesthesia for elderly patients undergoing surgical stabilisation of proximal femoral fractures. The study's primary objective is to compare two spinal anaesthesia techniques: the continuous method (investigational), which allows titration of local anaesthetic doses through a catheter placed in the subarachnoid space, and the conventional single-shot bolus injection. The main hypothesis is that the continuous catheter technique reduces the incidence of intraoperative hypotension and related complications, such as delirium, acute kidney injury, and cardiovascular events. Beyond haemodynamic stability-assessed through advanced continuous monitoring of cardiac output and vascular resistance-the study will evaluate early and late complications, as well as quality of life up to 24 months post-surgery. The project is a prospective, randomised, multicentre clinical trial including at least 216 patients over 50 years of age, randomly assigned to one of the two groups. Proximal femoral fractures are a major and growing global health issue, particularly among geriatric patients with multiple comorbidities. The conventional single-shot spinal anaesthesia, though widely used, carries a high risk of hypotension, potentially leading to delirium, acute kidney injury, stroke, and cardiac events. These complications worsen prognosis, decrease quality of life, and increase mortality. Most existing studies are over two decades old, based on small cohorts and outdated anaesthetic protocols, and lack long-term follow-up data (\>30 days) on neurological outcomes, functional recovery, quality of life, and mortality. Moreover, no modern trials have provided direct, comprehensive comparisons between single-shot and continuous spinal anaesthesia. This project therefore seeks to fill this critical evidence gap through a robust randomised clinical trial. Using precise, continuous measurements of arterial pressure, vascular resistance, and cardiac output, alongside long-term assessments of neurological outcomes, quality of life, and survival, it aims to determine whether continuous spinal anaesthesia offers superior safety and should become the new standard of care for this vulnerable population.

Revision total knee arthroplasty (rTKA) is a frequently performed procedure. Adequate pain management is an important feature, especially for fast-track and Enhanced Recovery After Surgery (ERAS) programs. The multimodal approach, including single shot or continuous nerve blocks with catheters and spinal or epidural morphine, is a stablished strategy. Although the administration of intrathecal morphine (IM) has been shown to significantly reduce pain scores, it is not free of adverse effects. Postoperative urinary retention (POUR) is possible and might increase the risk of periprosthetic infection. The purpose of this study is to compare patients undergoing rTKAS under spinal anesthesia with IM to patients undergoing the same procedure, under the same anesthetic technique, but with no IM, for POUR and postoperative pain related outcomes. All patients will have single shot and continuous adductor canal block (CACB) and single shot IPACK (interspace between the popliteal artery and the posterior knee capsule) block. The hypothesis is that postoperative pain control is comparable between the groups, with lower incidence of POUR in patients with no IM given.

This study aims to compare two medications, dexmedetomidine and fentanyl, when used alongside a commonly used spinal anesthetic called bupivacaine in patients undergoing lower limb surgery. The main focus of the study is to see which combination causes fewer problems with urination after surgery - a condition known as postoperative urinary retention (POUR). POUR can lead to discomfort, delayed recovery, and a need for catheterization. Dexmedetomidine is a newer drug that may help reduce this problem compared to fentanyl, which is more commonly used but may increase the risk of urinary retention. This trial will help determine which medication combination provides better pain relief while reducing urinary side effects. The study is being conducted as a randomized, double-blind trial at a hospital in Nepal and will include 190 adult patients. \-

The goal of this pilot clinical trial is to test the feasibility of conducting a randomized controlled trial that will examine the use of ropivacaine in the spinal anesthesia for patients undergoing elective 1- or 2-level lower spine surgery. This study aims to: * Determine the rates of eligibility, recruitment, consent, and attrition * Determine the acceptability among patients, surgeons, anesthesiologists, and nurses of doing spine surgery under spinal anesthesia * Gather preliminary data on outcomes relevant to a future dose-finding study Participants will be randomized to one of three treatment groups: * General anesthesia with endotracheal tube * Spinal anesthesia with bupivacaine * Spinal anesthesia with ropivacaine

In this prospective, randomized, single-blind study, we aim to compare the effects of general anesthesia and spinal anesthesia on postoperative myocardial injury in elderly patients undergoing hip surgery. Cardiovascular events are a leading cause of mortality and morbidity following non-cardiac surgery, with myocardial injury after non-cardiac surgery (MINS) being a significant concern. MINS, characterized by asymptomatic elevation of troponin levels without accompanying ECG findings, is closely associated with postoperative mortality. With the increasing prevalence of comorbidities in the elderly population and the rising frequency of non-cardiac surgeries in this demographic, understanding the effects of different anesthesia types on postoperative myocardial injury is crucial.