Selection Of Anesthetic Agents Research Articles

Impact of propofol and sevoflurane anesthesia on cognition and emotion in gastric cancer patients undergoing radical resection.

Propofol and sevoflurane are commonly used anesthetic agents for maintenance anesthesia during radical resection of gastric cancer. However, there is a debate concerning their differential effects on cognitive function, anxiety, and depression in patients undergoing this procedure. To compare the effects of propofol and sevoflurane anesthesia on postoperative cognitive function, anxiety, depression, and organ function in patients undergoing radical resection of gastric cancer. A total of 80 patients were involved in this research. The subjects were divided into two groups: Propofol group and sevoflurane group. The evaluation scale for cognitive function was the Loewenstein occupational therapy cognitive assessment (LOTCA), and anxiety and depression were assessed with the aid of the self-rating anxiety scale (SAS) and self-rating depression scale (SDS). Hemodynamic indicators, oxidative stress levels, and pulmonary function were also measured. The LOTCA score at 1 d after surgery was significantly lower in the propofol group than in the sevoflurane group. Additionally, the SAS and SDS scores of the sevoflurane group were significantly lower than those of the propofol group. The sevoflurane group showed greater stability in heart rate as well as the mean arterial pressure compared to the propofol group. Moreover, the sevoflurane group displayed better pulmonary function and less lung injury than the propofol group. Both propofol and sevoflurane could be utilized as maintenance anesthesia during radical resection of gastric cancer. Propofol anesthesia has a minimal effect on patients' pulmonary function, consequently enhancing their postoperative recovery. Sevoflurane anesthesia causes less impairment on patients' cognitive function and mitigates negative emotions, leading to an improved postoperative mental state. Therefore, the selection of anesthetic agents should be based on the individual patient's specific circumstances.

Paving the way to environment-friendly greener anesthesia.

Health-care settings have an important responsibility toward environmental health and safety. The operating room is a major source of environmental pollution within a hospital. Inhalational agents and nitrous oxide are the commonly used gases during general anesthesia for surgeries, especially in the developing world. These greenhouse gases contribute adversely to the environmental health both inside the operating room and in the outside atmosphere. Impact of these anesthetic agents depends on the total consumption, characteristics of individual agents, and gas flows, with higher levels increasing the environmental adverse effects. The inimical impact of nitrous oxide is higher due to its longer atmospheric half-life and potential for destruction of the ozone layer. Anesthesiologist of today has a choice in the selection of anesthetic agents. Prudent decisions will help in mitigating environmental pollution and contributing positively to a greener planet. Therefore, a shift from inhalational to intravenous-based technique will reduce the carbon footprint of anesthetic agents and their impact on global climate. Propofol forms the mainstay of intravenous anesthesia technique and is a proven drug for anesthetic induction and maintenance. Anesthesiologists should appreciate growing concerns about the role of inhalational anesthetics on the environment and join the cause of environmental responsibility. In this narrative review, we revisit the pharmacological and pharmacokinetic considerations, clinical uses, and discuss the merits of propofol-based intravenous anesthesia over inhalational anesthesia in terms of environmental effects. Increased awareness about the environmental impact and adoption of newer, versatile, and user-friendly modalities of intravenous anesthesia administration will pave the way for greener anesthesia practice.

Updates in Prevention of Surgical Site Infection: Comment.

Long et al.1 provided a well-written and accessible review of new ideas in the field of surgical site infection prevention. Within their discussion of the patient’s microbiome, the authors touch on the potential for interactions between the patient microbiome and anesthetic agents administered perioperatively. Although they accurately identify the immunosuppressive potential of volatile anesthetics and intravenous opioids, we think that it is important to note that there exist other agents capable of producing and maintaining general anesthesia. Medications like ketamine and propofol are immunomodulatory in different ways, and thus their use may also impact the development of surgical site infections.Long et al.1 cite two mouse model articles where exposure to volatile anesthetics was associated with a decrease in intestinal microbiome diversity.2,3 In contrast, Guo et al.,4 using a rat model, looked at the effect of a continuous infusion of propofol during a 3-h period on the intestinal microbiome and found little change in the diversity of the intestinal microbiome after exposure to propofol. Similarly, Gerb et al.5 looked at the effects on the intestinal microbiome of mice after 10 daily exposures to a bolus dose of ketamine that rendered the mice unconscious for approximately 15 to 30 min per ketamine exposure and also found little change in the diversity of the intestinal microbiome.No definitive evidence exists to recommend one type of anesthetic over another. Given the minimal impact on the intestinal microbiome, it might be tempting to conclude that replacing volatile anesthetics with agents such as propofol and ketamine might decrease the incidence of surgical site infection. But there is also evidence to the contrary. For example, Visvabharathy et al.6 looked at susceptibility to infection due to exogenous bacteremia using Listeria and Staphylococcus aureus in mice receiving intravenous propofol compared to mice receiving intravenous ketamine with xylazine and found that propofol increased susceptibility to infection. In a research letter, Liu et al.7 looked at the intestinal microbiome in 21 patients undergoing nephrectomy with propofol alone compared to sevoflurane alone compared to propofol and sevoflurane combined and found that the mixed anesthetic7 was associated with the fewest perturbations.Clearly it remains premature to advocate for a total intravenous technique in the absence of more clinically robust data. Further research in animal models and in humans is needed to try and elucidate not only if there is an optimal anesthetic agent for prevention of surgical site infection, but also what the combined effects of multiple anesthetics, as routinely administered when patients present for surgery, have on the patient’s susceptibility to infection after surgery.Surgical site infections are a multidisciplinary problem. Once more data are available, it may turn out that the effects of anesthetic agents are small and of minor importance in patients with normal immune systems. But the selection of anesthetic agents is one aspect we have almost complete control over; we should be making every effort to maximize the ability of the patient’s immune system to combat infection.The authors declare no competing interests.

Monitoring Differences in Vaginal Hemodynamic and Temperature Response for Sexual A rousal by Different Anesthetic Agents Using an Optical Probe

The selection of anesthetic agent is important in preclinical studies, since each agent affects the systemic hemodynamics in different ways. For that reason, we hypothesized that different anesthetic agents will result in different vaginal hemodynamic response and temperature during sexual arousal, in an animal model. To validate the hypothesis, animal experiments were performed using female rats with two anesthetic agents widely used in preclinical studies: ketamine and isoflurane. Our previously developed near-infrared-spectroscopy-based probe was used to measure the changes of oxyhemoglobin (OHb), deoxyhemoglobin (RHb), and total hemoglobin (THb) concentrations along with temperature from the animal vaginal wall. As a control, saline was administered to both isoflurane- and ketamine-anesthetized animals, and did not show any significant changes in OHb, RHb, THb, or temperature. However, an administration of apomorphine (APO, 80 μg/kg) induced increases of OHb (63 ± 28 μM/DPF), RHb (35 ± 20 μM/DPF), and THb (98 ± 49 μM/DPF) in ketamine-anesthetized animals, while decreases of OHb (52 ± 76 μM/DPF) and THb (38 ± 30 μM/DPF) and an increase of RHb (28 ± 51 μM/DPF) were found in isoflurane-anesthetized animals. The vaginal temperature decreased from the baseline in both ketamine-(0.42°C) and isoflurane-(1.22°C)anesthetized animals. These results confirmed our hypothesis, and suggest that a preclinical study monitoring hemodynamic responses under anesthesia should employ an appropriate anesthetic agent for the study.

S16-2. Strategy in anesthetic management for intraoperative neuromonitoring

The development of postoperative functional dysfunction can have an impact on the length of hospital stay, total medical costs, and necessity of dependency. To maintain functional integrity, neuromonitoring including motor evoked potential (MEP), sensory evoked potential, and visual evoked potential, has been conducted during the operation. Anesthetic management is usually based on the maintenance of MEP, which is most susceptible to suppression by anesthetic agents. MEP is indicated for craniotomy, spine surgery and aortic surgery, in which the technique for stimulation and recording can vary on types of surgery. Especially, stimulus intensity and technique should be carefully applied for craniotomy. Anesthetic management remains to be challenging during MEP monitoring in aortic surgery, in which cardiopulmonary bypass with aortic occlusion and hypothermia is conducted. In pediatric cases, the selection of anesthetic agents and monitoring of anesthetic depth remained to be debated. Anesthetic fade of MEP in prolonged surgery is possible topic to be overcomed. Although the use of remifentanil and sugamadex made anesthetic management for MEP easy, patient’s movement and bite injury in response to stimulation seem to be a problem, which needs to be resolved. Safety management of multidisciplinary monitoring team is also important issue for further progress.

The effects of pentobarbital, ketamine-pentobarbital and ketamine-xylazine anesthesia in a rat myocardial ischemic reperfusion injury model.

To achieve reliable experimental data, the side-effects of anesthetics should be eliminated. Since anesthetics exert a variety of effects on hemodynamic data and incidence of arrhythmias, the selection of anesthetic agents in a myocardial ischemic reperfusion injury model is very important. The present study was performed to compare hemodynamic variables, the incidence of ventricular arrhythmias, and infarct size during 30 min of ischemia and 120 min of reperfusion in rats using pentobarbital, ketamine-pentobarbital or ketamine-xylazine anaesthesia. A total of 30 rats were randomly divided into three groups. In group P, pentobarbital (60 mg/kg, intraperitoneally [IP]) was used solely; in group K-P, ketamine and pentobarbital (50 and 30 mg/kg, respectively, IP) were used in combination; and in group K-X, ketamine and xylazine (75 and 5 mg/kg, respectively, IP) were also used in combination. Hemodynamic data and occurrence of ventricular arrhythmias were recorded throughout the experiments. The ischemic area was measured by triphenyltetrazolium chloride staining. The combination of ketamine-xylazine caused bradycardia and hypotension. The greatest reduction in mean arterial blood pressure during ischemia was in the P group. The most stability in hemodynamic parameters during ischemia and reperfusion was in the K-P group. The infarct size was significantly less in the K-X group. Whereas none of the rats anesthetized with ketamine-xylazine fibrillated during ischemia, ventricular fibrillation occurred in 57% of the animals anesthetized with pentobarbital or ketamine-pentobarbital. Because it offers the most stable hemodynamic parameters, it is concluded that the ketamine-pentobarbital anesthesia combination is the best anesthesia in a rat ischemia reperfusion injury model.

Lowe's syndrome with Fanconi syndrome for ocular surgery: perioperative anesthetic considerations

Lowe's syndrome is a rare inherited metabolic disorder characterized by mental retardation, kidney malfunction, and abnormalities of the eyes and bones. A 4 month-old child with Lowe's and Fanconi's syndrome, undergoing bilateral congenital cataract surgery, is presented. Preoperative electrolyte imbalance was corrected by potassium, calcium, magnesium, phosphate, and bicarbonate supplementation. Anesthesia was administered uneventfully using appropriate anesthetic agents and monitoring. Adequate preoperative evaluation and optimization, along with selection of anesthetic agents and fluid and electrolyte management with appropriate perioperative monitoring, is key to a successful outcome.

The incidence of pneumocephalus after supratentorial craniotomy. Observations on the disappearance of intracranial air.

Pneumocephalus occurs in a variety of clinical settings and has important anesthetic implications, particularly if N2O is used. One common cause of pneumocephalus is a craniotomy or craniectomy, and therefore, patients undergoing these neurosurgical procedures may be at increased risk for the development of tension pneumocephalus if N2O is used during a subsequent anesthetic. However, because the rate at which a postoperative pneumocephalus resolves has not been well defined, the duration of this risk period is unknown. Department of Anesthesia billing codes were used to identify all patients undergoing supratentorial craniotomy between 1986 and 1990. This list was cross-indexed with Department of Radiology data to generate a list of patients who had had a computed tomographic scan of the head performed on or after the day of their surgery. From this list, 240 scans were examined for the presence of intracranial air. The magnitude of pneumocephalus, if present, was ranked as large, moderate, small, or trace. Air was seen in all scans obtained in the first 2 post-operative days. Sixty-six percent of these pneumocephali were judged to be moderate or large. The incidence of pneumocephalus decreased to 75% by postoperative day 7. During the 2nd and 3rd postoperative weeks, the incidence of pneumocephalus decreased to 59.6 and 26.3%, respectively. The size of the pneumocephali also decreased. Still, 11.8% of the scans obtained during the 2nd postoperative week had pneumocephali that were judged to be moderate or large. These data indicate that all patients have pneumocephalus immediately after a supratentorial craniotomy. Although the incidence and size of pneumocephali decrease over time, a significant number of patients have an intracranial air collection large enough to put them at risk for complication if N2O is used during a second anesthetic in the first 3 weeks after the first procedure. This information should be considered in the evaluation of the patient and in the selection of anesthetic agents.

General anesthetic techniques.

General anesthesia is the most common form of anesthetic management for ambulatory surgery. Patients, in general, prefer general anesthesia because it is less anxiety provoking. During the last decade, the availability of several short-acting agents with high clearance has made general anesthetic techniques much safer and more predictable for outpatients. Besides, general anesthesia today is associated with a quick and full recovery with minimal postoperative side effects. Proper preanesthetic psychological and, when necessary, pharmacological preparation as well as proper selection of anesthetic agents are the keys to the success of general anesthetic technique for ambulatory surgery. Although both TIVA and total inhalation anesthetic techniques have their advocates, balanced anesthesia is most popular. The introduction of several new agents (e.g., propofol, desflurane, vecuronium, atracurium, mivacurium, rocuronium, alfentanil, ondansetron, ketorolac) has made ambulatory general anesthesia less challenging and more interesting. In the future, the new anesthetic sevoflurane, and the new opioid remifentanil, may prove useful for ambulatory anesthesia. The LMA has all but revolutionized airway management during general anesthesia for ambulatory surgery.

Clinical Evaluation of Cesarian Section Anerohesia

Maternal and fetal effects of anesthesia for 423 cesarian section, performed during the past three and quarter years period in this hospital, have been evaluated. It is emphasized that the selection of anesthetic agent and method should depend upon the physical status of the patients and the ability of both obstetrician and anesthesiologists. Author results were as follows: 1. The incidence of c-section was 13.9% of total deliveries. 2. More than about three fourths of total cases were emergency cases. 3. Almost all cases were operated under general anesthesia. 4. The good physical states of patients resulted in better Apgar score of infants. 5. The shorter the interval from induction of anesthesia to delivery, the better was the Apgar score of infants.

Anesthesia in Otolaryngology and Ophthalmology

This text contains much useful information in two areas of anesthesia. It stems from the extensive experience of an anesthesiologist who for many years has specialized in anesthesia for otolaryngology and ophthalmology. Frequently in the practice of anesthesiology, there may be several options available in the selection of anesthetic agents and techniques. However, in this book, the impression is given that the author has limited his recommendations to his own particular preferences. The middle sections on anesthesia in otolaryngology and ophthalmology contain useful descriptions of the surgical procedures involved and the special anesthetic requirements that must be met to ensure a successful outcome. Since many ophthalmic procedures can be performed under local anesthesia, the chapter on Topical, Infiltration, and Nerve Block Anesthesia provides a background of information that will be helpful to both anesthesiologists and ophthalmologists in the choice of local or general anesthesia. Section 1, General Considerations, is a

Anesthetic considerations for pericardectomy in uremic pericardial effusion.

Fifteen patients with impending uremic cardiac tamponade underwent either anterior pericardectomy or pericardiostomy under general anesthesia. Anesthetic agents and technics were selected in the light of physiopathologic derangements involving fluids and electrolyte balance, excretory and cardiovascular disturbances, and pharmacodynamics. Anesthesia was induced with diazepam and maintained with N2O-O2 (70:30) and fentanyl. Pancuronium was used for muscle relaxation. Adequate preoperative assessment of patient, careful monitoring of vital signs, maintenance of the critical balance of fluid and blood replacement, and selection of anesthetic agents for minimal depression of vital multiorgan systems provided excellent results. No postanesthetic morbidity or mortality occurred.

Anesthesia in Otolaryngology and Ophthalmology

This text contains much useful information in two areas of anesthesia. It stems from the extensive experience of an anesthesiologist who for many years has specialized in anesthesia for otolaryngology and ophthalmology. Frequently in the practice of anesthesiology, there may be several options available in the selection of anesthetic agents and techniques. However, in this book, the impression is given that the author has limited his recommendations to his own particular preferences. The middle sections on anesthesia in otolaryngology and ophthalmology contain useful descriptions of the surgical procedures involved and the special anesthetic requirements that must be met to ensure a successful outcome. Since many ophthalmic procedures can be performed under local anesthesia, the chapter on Topical, Infiltration, and Nerve Block Anesthesia provides a background of information that will be helpful to both anesthesiologists and ophthalmologists in the choice of local or general anesthesia. Section 1, General Considerations, is a

The selection of anesthetic agents and their administration for dental office procedures

The selection of anesthetic agents and their administration for dental office procedures