Balanced Total Intravenous Anesthesia Research Articles

Multidisciplinary difficult airway challenges: Perioperative management of glottic and supraglottic tumors

Carcinomas of the larynx are common and require multidisciplinary perioperative management, with particularly excellent communication between the surgeon and anesthesiologist. Early preoperative assessment allows for optimization, prehabilitation and advanced imaging in cases who present without respiratory compromise. On arrival for surgery, thorough airway examination including preoperative endoscopic airway assessment under topical anesthesia and airway ultrasound will inform planning for airway management. The fundamental decision between awake tracheal intubation or awake tracheostomy, and intubation after induction of anesthesia should be made as a team, with strategies for failure (such as rigid bronchoscopy or emergency surgical airway) clearly defined, and staff and equipment present. Balanced total intravenous anesthesia with target-controlled infusions allow good analgesia and smooth emergence. Admission to a postanesthesia high care environment is advisable.

Anaesthetic and cardiopulmonary evaluation following xylazine-Diazepam-ketamine-propofol administration with or without local infiltration analgesia using mepivacaine during inguinal castration in Donkeys

The present study was performed to investigate the cardiopulmonary responses and hypoalgesic efficacy of diazepam/ketamine anaesthesia induction followed by xylazine-propofol infusion alone (XDKP) or with a local infiltration of mepivacaine (XDKPM) for inguinal castration in donkeys. A 10 male adult donkeys were assigned to two groups (XDKP and XDKPM). Donkeys were sedated by xylazine then anaesthesia was inducted with followed by diazepam/ketamine. Anaesthesia was maintained by propofol infusion 0.1 mg/kg/h. XDKPM group, mepivacaine 2% were locally infiltrated on each side and two min before surgical incision. Both group got smooth induction and recovery. The pain scale scores showed a significant higher compared to baseline in both groups. In conclusion, a combination of XDKP is balanced total intravenous anaesthesia regimen with cardiopulmonary stability in donkeys undergoing inguinal castration. Keywords: xylazine, propofol, mepivacaine, inguinal castration, donkey

Reviews of Modeling Techniques for Neuromonitoring Depth of Anesthesia.

This article reviews the various modeling techniques for neuromonitoring depth of anesthesia (DOA). Traditional techniques such as parametric, predictive, optimal, and adaptive modeling; proportional, integral, derivative (PID) modeling; together with modern techniques such as bispectral-based, artificial neural-network-based, fuzzy logic, and neuro-fuzzy modeling, bring us to the current state of the art in DOA neuromonitoring. This article reviews historical information about each of the modern techniques and provides an example demonstrating its implementation; reviews drug pharmacokinetic/pharmacodynamic (PK/PD) and drug interaction PK/PD modeling techniques for a balanced total intravenous anesthesia (TIVA) administration; and discusses the existing technical problems and clinical challenges, suggesting new techniques necessary for the future development of a DOA monitoring and control system.

Intravenous anesthesia for thoracic procedures

The article reviews the rationale for using intravenous anesthesia for thoracic operations, the drugs and equipment required, and the methodology involved. Recent studies examining whether total intravenous anesthesia offers a physiological advantage over inhalational anesthesia for thoracic surgery remain inconclusive. Nevertheless, total intravenous anesthesia is preferable for certain thoracic procedures incompatible with effective delivery of inhalational anesthetics. Additionally, total intravenous anesthesia offers advantages in procedures conducted in nonideal environments, such as offsite or austere scenarios. Total intravenous anesthesia is indicated for procedures in which inhalational anesthetics may not be safely or effectively delivered, including endobronchial procedures using flexible or rigid bronchoscopy and proximal airway-disrupting surgeries. Total intravenous anesthesia may be beneficial in lung volume reduction surgery, lung transplantation and thymectomy. Total intravenous anesthesia is safer and more practical for thoracic procedures performed outside of the operating room, such as offsite locations, military field or impoverished areas of the world. Propofol, dexmedetomidine, ketamine and remifentanil may be used in combination with anesthetic depth monitoring to execute an effective total intravenous anesthesia regimen. Target-controlled infusion may improve the delivery of total intravenous anesthesia and is a focus for future research. This article reviews the balanced total intravenous anesthesia technique currently used at the University of Texas M.D. Anderson Cancer Center.

Modeling for neuromonitoring depth of anesthesia.

This article reviews the various modeling techniques for neuromonitoring depth of anesthesia (DOA). Traditional techniques such as parametric, predictive, optimal, and adaptive modeling, proportional, integral, derivative (PID) modeling, together with modern techniques such as bispectral-based, artificial neural-network-based, fuzzy logic, and neuro-fuzzy modeling, bring us to the current state of the art in DOA neuromonitoring. This article reviews historical information about each of the modern techniques and provides an example demonstrating its implementation; reviews drug pharmacokinetic/pharmacodynamic (PK/PD) and drug interaction PK/PD modeling techniques for a balanced total intravenous anesthesia (TIVA) administration; and discusses the existing technical problems and clinical challenges, suggesting new techniques necessary for the future development of a DOA monitoring and control system.

Con: Midazolam is not the sedative of choice to supplement narcotic anesthesia

T HE DOSE-RESPONSE curve for narcotic or opioid anesthesia is not linear but reaches a plateau beyond a certain plasma concentration.‘J In patients undergoing cardiac surgery, increasing the plasma concentration of fentanyl above 20 ng/mL had little effect on the incidence of hypertension following sternotomy or aortic dissection.2,3 Similarly, high-dose opioid anesthesia using sufentanil or alfentanil has not suppressed breakthrough hypertension.4v5 Episodes of patient awareness are associated with this anesthetic technique,6 and also time to extubation is prolonged. If increasing the dose of opioid does not produce better suppression of hemodynamic responses to noxious stimuli, it seems more appropriate that a smaller dose of opioid is used to provide analgesia and another agent to provide anesthesia. Providing unconsciousness and amnesia is essential during highly stressful cardiac surgery, and, because opioids, by the nature of their action, are not expected to produce these effects,’ the addition of a hypnotic drug to a moderate or balanced dose of opioid would seem to be a logical approach to anesthetizing patients. The application of balanced total intravenous anesthesia in the context of cardiac surgery has in the past been limited by the availability of agents that are pharmacokinetically suited to continuous infusion. The advent of new short-acting drugs means that the component of hypnosis, analgesia and reflex suppression can now be provided by infusions that are independently titrated. Analgesia is provided by either a continuous infusion or by intermittent injection of one of the opioids, but using much lower total doses. The adjuvants frequently used are midazolams or propofol.’ Although midazolam is a good sedative and provides amnesia, it does have hemodynamic side effects that may not be beneficial during anesthesia for cardiac surgery. Midazolam exerts its major hemodynamic effects at the peripheral level with a small decrease in systemic vascular resistance but marked venodilatation.8J0 By decreasing the venous return, preload is reduced, which may contribute to a fall in cardiac output and blood pressure. Maintenance of the cardiac output greatly depends on compensatory mechanisms such as increased baroreceptor activity, blood mobilization from the splanchnic area and increased sympathetic tone. In patients with hypovolemia, hypertension and P-adrenergic blockade, impairment of these compensatory mechanisms has been reported to induce serious hypotensive episodes.” These have been described in patients with severe noncardiac systemic illness, in whom midazolam

Balanced Total Intravenous Anaesthesia and Intraocular Pressure

Twenty patients, aged 21 to 48 years and rated ASA physical status I, were studied during ophthalmic surgery. Ten subjects (Group I) received thiopentone, halothane and nitrous oxide in oxygen, and ten (Group II) received total intravenous anaesthesia, using flunitrazepam and ketamine. Ventilation was controlled mechanically with the aid of a muscle relaxant. Both anaesthetic techniques caused a significant decrease in intraocular pressure. After an initial decline in systolic arterial pressure and an increase in heart rate, cardiovascular status was well maintained in the two series. Side effects were uncommon with both techniques. Balanced total intravenous anaesthesia with flunitrazepam, ketamine and relaxant appears to offer a safe alternative to conventional inhalation narcosis for intraocular surgery.