Safety and efficacy of target-controlled infusion versus intermittent bolus administration of propofol for sedation in colonoscopy: a randomized controlled trial

Abstract Background: Our objective was to compare the safety and efficacy of Target-Controlled Infusion (TCI) versus intermittent bolus of propofol for colonoscopy sedation. Methods: We conducted a randomized (1:1), single-blind, parallel-group superiority trial with fifty ASA I or II patients, both sexes, aged 18 to 65 years, Body Mass Index ≤ 30 kg.mr-2, undergoing colonoscopy, allocated to receive propofol by TCI (effect-site, 2 μg.mL-1 plus 0.5 μg.mL-1 until unconsciousness and as necessary for agitation) or intermittent bolus (1 mg.kg-1 plus 0.5 mg.kg-1 every 5 minutes or as above). The primary safety outcome was the need for airway maneuvers and the primary efficacy outcome was the need for interventions to adjust the level of sedation. Secondary outcomes included incidence of agitation, propofol dose, and time to recovery. Results: The median (IQR) number of airway maneuvers and interventions needed to adjust sedation was 0 (0-0) vs. 0 (0-0) (p = 0.239) and 1 (0-1) vs. 3 (1-4) (p < 0.001) in the TCI and control groups, respectively. Agitation was more common in the intermittent bolus group - 2 (0-2) vs. 1 (0-1), p < 0.001. The mean ± SD time to recovery was 4.9 ± 1.4 minutes in the TCI group vs. 2.3 ± 1.6 minutes in the control group (p < 0.001). The total propofol dose was higher in the TCI group (234 ± 46 μg.kg-1.min-1 vs. 195 ± 44 μg.kg-1.min-1 (p = 0.040)). Conclusions: During colonoscopy, TCI is as safe as intermittent bolus of propofol while reducing the incidence of agitation and the need for dose adjustments. However, intermittent bolus administration was associated with lower total propofol dose and earlier recovery.

Association between anesthesia regimen and postoperative infection in patients undergoing cardiac surgery: A retrospective cohort study / 中国胸心血管外科临床杂志

@#Objective     To evaluate the association between anesthesia regimen (volatile or intravenous anesthetics) and postoperative infection in adult cardiac patients undergoing cardiac surgery. Methods    The clinical data of 496 elective adults undergoing cardiac surgery under cardiopulmonary bypass from June 2019 to June 2020 in West China Hospital of Sichuan University were retrospectively analyzed, including 251 females and 245 males with an average age of 54.1±11.4 years. American Society of Anesthesiologists grade was Ⅰ-Ⅲ. There were 243 patients in a volatile group with sevoflurane or desflurane, and 253 patients in an intravenous anesthesia group with propofol. The primary outcome was the incidence of infection within 30 days after cardiac surgery, including pulmonary infection, surgical site infection, sepsis, and urinary tract infection. The secondary outcomes were duration of mechanical ventilation, incidence of reintubation, ICU stay, postoperative length of hospital stay and total hospitalization cost. Results     A total of 155 (31.3%) patients developed postoperative infection within 30 days, with an incidence of 32.9% in the volatile group and 29.6% in the intravenous anesthesia group. There was no statistical difference in the incidence of infection (RR=1.111, 95%CI 0.855 to 1.442, P=0.431) or the secondary outcomes (P>0.05) between the two groups. Conclusion     The anesthesia regimen (volatile or intravenous anesthetics) has no association with the risk of occurrence of postoperative infection in adult  patients undergoing elective cardiac surgery with cardiopulmonary bypass.

Anesthetics, analgesics and cognitive function / 中国临床药理学与治疗学

Cognitive dysfunction has become a pivotal factor affecting the quality of life of elderly patients. The existing literatures can not explain the factors causing cognitive decline. Many researchers believe that anesthetics and analgesics may play important roles in cognitive dysfunction. This review will discuss the effects of different anesthetics and analgesics on cognitive function and briefly describe their mechanisms, so as to provide reference for the rational choice of medications in clinical practice.

The effect of propofol when injected at different speeds for induction of general anesthesia: an observational study

Background:The hypotensive effect of propofolis attributable to a decrease in sympathetic activity,direct vasodilatation and myocardial depression. The aim of the study wasto assessthe effect of propofol when injected at different speeds for induction of general anesthesia on the following parameters:blood pressure,time of induction of anesthesia,dose of propofol used.Methods:The present study was conducted in post Graduate Department of Anesthesia and Surgery, Govt. Medical College,Srinagar for a period of two years and included 90 patients from July 2014 to June16,the study was prospective one.Results:In our study patients divided into three groups with 30 patients in each group.The mean age in group P400,P600,P800 wasstatistically insignificant p>0.843.The mean weight in group P400, P600, P800 was statistically insignificant p>0.885.The mean height in group P400,P600,P800 was statistically insignificant p>0.748.The mean induction time in P400 and in P600 was statistically significant.The mean systolic blood pressure, pre and post induction in P400,in P600 and in group P800 was statistically significant. The mean diastolic blood pressure, in pre and post induction in P400,P600,P800 was statistically insignificant with a p>0.05.The mean arterial pressure in pre and post induction in P400,P600,P800 was statistically significant (p<0.05).The mean heart rate in pre and post induction was statistically insignificant. The mean oxygen saturation (%) pre and post induction was statistically insignificant. Conclusions: We concluded that induction dose required for loss of consciousness increased with a faster rate of infusion while time for induction was shorter in P800 compared to P400 and P600, and the decrease in mean blood pressure was less after induction in P400.Propofol injection should be slow enough to prevent any hemodynamic deterioration in anesthesia induction

Current trends in intravenous sedative drugs for dental procedures

Anxiety and phobia in dental procedures are common deterrents for patients visiting the dental care unit. For these individuals, procedural sedation may aid in completion of dental treatments. In most cases, the patients are conscious during sedation, thereby allowing spontaneous ventilation. Intravenous sedation (IVS) is widely used during dental treatment to relieve patient anxiety. IVS is the most effective route of administration to achieve this goal, but it requires advanced training, more than that provided during undergraduate education. During IVS, rapid onset, repetitive drug administration, easy titration, and rapid recovery from sedation can be achieved. However, conscious sedation during IVS can result in deep sedation that can cause respiratory and cardiovascular depression. Therefore, the characteristics of intravenous sedatives should be known. The purpose of this review is to discuss the characteristics and usage of intravenous sedatives currently used for dental procedures.

Current trends in intravenous sedative drugs for dental procedures

Anxiety and phobia in dental procedures are common deterrents for patients visiting the dental care unit. For these individuals, procedural sedation may aid in completion of dental treatments. In most cases, the patients are conscious during sedation, thereby allowing spontaneous ventilation. Intravenous sedation (IVS) is widely used during dental treatment to relieve patient anxiety. IVS is the most effective route of administration to achieve this goal, but it requires advanced training, more than that provided during undergraduate education. During IVS, rapid onset, repetitive drug administration, easy titration, and rapid recovery from sedation can be achieved. However, conscious sedation during IVS can result in deep sedation that can cause respiratory and cardiovascular depression. Therefore, the characteristics of intravenous sedatives should be known. The purpose of this review is to discuss the characteristics and usage of intravenous sedatives currently used for dental procedures.

How to design intravenous anesthetic dose regimens based on pharmacokinetics and pharmacodynamics principles

Pharmacokinetics is the study of the rate and degree of drug transport to various tissues in the human body. Pharmacokinetic parameters summarize drug kinetics and ideally predict a clinical situation. A single kinetic profile may be summarized by peak concentration, peak time, half-life and area under the curve. Dosage regimens are designed to confer the maximum desired effects for the required time period with minimal toxicity. Target-controlled infusions use pharmacokinetic models to titrate intravenous anesthetic administration to achieve a desired drug concentration. Context-sensitive half time is used to predict the clinical time course, rather than terminal half-life. It is important that anesthesiologists understand the basic pharmacological principles and apply them in their daily clinical practice. This review discusses the ways in which anesthesiologists can design a patient-specific dosage regimen of intravenous anesthetics by utilizing basic concepts of pharmacokinetics and pharmacodynamics using pharmacokinetic simulations.

Concerns of the anesthesiologist: anesthetic induction in severe sepsis or septic shock patients / 대한마취과학회지

Septic patients portray instable hemodynamic states because of hypotension or cardiomyopathy, caused by vasodilation, thus, impairing global tissue perfusion and oxygenation threatening functions of critical organs. Therefore, it has become the primary concern of anesthesiologists in conducting anesthesia (induction, maintenance, recovery, and postoperative care), especially in the induction of those who are prone to fall into hemodynamic crisis, due to hemodynamic instability. The anesthesiologist must have a precise anesthetic plan based on a thorough preanesthetic evaluation because many cases are emergent. Primary circulatory status of patients, including mental status, blood pressure, urine output, and skin perfusion, are necessary, as well as more active assessment methods on intravascular volume status and cardiovascular function. Because it is difficult to accurately evaluate the intravascular volume, only by central venous pressure (CVP) measurements, the additional use of transthoracic echocardiography is recommended for the evaluation of myocardial performance and hemodynamic state. In order to hemodynamically stabilize septic patients, adequate fluid resuscitation must be given before induction. Most anesthetic induction agents cause blood pressure decline, however, it may be useful to use drugs, such as ketamine or etomidate, which carry less cardiovascular instability effects than propofol, thiopental and midazolam. However, if blood pressure is unstable, despite these efforts, vasopressors and inotropic agents must be administered to maintain adequate perfusion of organs and cellular oxygen uptake.

Pain reduction on injection of microemulsion propofol via combination of remifentanil and lidocaine / 대한마취과학회지

BACKGROUND: Microemulsion propofol produces more frequent and severe pain upon injection than lipid emulsion propofol. This study examined the analgesic effect of lidocaine-premixed microemulsion propofol in patients pretreated with remifentanil. The induction of anesthesia with this combination was compared with microemulsion propofol accompanied with either remifentanil or lidocaine. METHODS: One hundred twenty patients aged between 20-65 years old were allocated randomly into one of three groups (n = 40, in each). The patients in the remifentanil group received remifentanil 0.5 microgram/kg IV for 30 seconds before a microemulsion propofol injection. The patients in the lidocaine group received propofol 2 mg/kg premixed with 40 mg lidocaine over a 60 second period. The patients in the combination group received both remifentanil and lidocaine. RESULTS: There was a significantly lower incidence of microemulsion propofol injection pain (severity 2 or more) in the combination group (12.5%) than in the remifentanil and lidocaine groups (90% and 65%, respectively, P < 0.05). The incidence of moderate pain disappeared completely in the combination group (0%) compared to that in the remifentanil and lidocaine group (32.5% and 20%, respectively, P < 0.05). Severe pain did not appear in any of the three groups. There were no complications on the injection site in the lidocaine alone and combination groups. CONCLUSIONS: The combination of microemulsion propofol premixed with lidocaine after a pretreatment with remifentanil was more effective in reducing the incidence of pain upon the injection of microemulsion propofol than either treatment alone.

K+ channel / 한양의대학술지

Potassium-selective channels are the largest and most diverse group of ion channels in the human. Also, potassium-selective channels are important in many cells during anesthesia. Many researches have focused on potassium channel and intravenous anesthetics.

Comparison of Emergence Agitation from Sevoflurane Anesthesia after Thiopental Sodium, Propofol or Ketamine Induction in Pediatric Inguinal Herniorrhaphy / 대한마취과학회지

BACKGROUND: This study compared the incidence of emergence agitation and the recovery profile from sevoflurane anesthesia after thiopental sodium, propofol or ketamine induction in pediatric inguinal herniorrhaphy. METHODS: Forty eight children aged 1-7 years undergoing high ligation due to an inguinal hernia were examined. All patients received a 0.004 mg/kg glycopyrrolate injection for premedication prior to induction and were randomly assigned to receive thiopental sodium 5 mg/kg (Group T, n = 16), propofol 2 mg/kg (Group P, n = 16) or ketamine 1 mg/kg (Group K, n = 16) for induction. The side effects during the induction time were checked. All patients received sevoflurane (2-2.5 vol%)-N2O (2 L/min)-O2 (2 L/min) for the maintenance of anesthesia. Ventilation was given to assist spontaneous ventilation using a facial mask. The agitation score, pain score, discharge score, incidence of emergence agitation and postoperative side effects in the three groups were assessed at the recovery room and compared. RESULTS: The emergence time in Group T (7.5 +/- 1.8 min) was significantly rapid. The agitation and pain scores were significantly low in Group P. The discharge score was more rapid in Groups P and K than in Group T. The incidence of emergence agitation was similar in all three groups. CONCLUSIONS: Although recovery was faster and emergence agitation was low in the propofol group, propofol induction was not smooth compared with thiopental or ketamine induction. The incidence of emergence agitation after sevoflurane anesthesia in pediatric inguinal herniorrhaphy was similar in the thiopental sodium, propofol or ketamine induction groups.

The Effects of Intravenous Anesthetics on Human Cytomegalovirus Infection / 대한마취과학회지

BACKGROUND: Reactivation of human cytomegalovirus (HCMV) from latency is a frequent complication of organ transplantation, and the molecular mechanism by which this occurs is unknown. Previous studies have shown that allogenaic transplantation combined with immunosuppression may be required to achieve complete reactivation in vivo and many anesthetics have wide range immunomodulatory properties. HCMV infection of endothelial cells plays an important role in the establishment of latency and persistence, which appears critical for the maintenance of HCMV within the host. METHODS: We compared the effects of intravenous anaesthetics (propofol, thiopental, and ketamine) on the susceptability of endothelial cells to HCMV infection by indirect immunofluorescent assay at 48 hour postinfection and we also have investigated the time course of luciferase gene expression in human umbilical vein endothelial cell (HUVEC) infected with recombinant HCMV. RESULTS: Treatment with anesthetics after HCMV strain Towne inoculation did not increase HUVEC susceptibility to HCMV infection by indirect immunofluorescent assay. Treatment of HUVEC with propofol, thiopental, and ketamine after the recombinant virus inoculation had no significant effects on the level of the late genes expression. CONCLUSIONS: Intravenous anesthetics (propofol, thiopental, and ketamine) did not increase the susceptability of endothelial cells to HCMV infection at plasma concentrations. Further studies are required to evaluate higher anesthetic concentration which may increases the susceptability of HUVEC to HCMV infection without cell destruction.

Effects of Thiopental Sodium, Midazolam, Propofol and Ketamine on Endothelial Nitric Oxide in Rat Thoracic Aortic Rings / 대한마취과학회지

BACKGROUND: Compared to inhalation and local anesthetics, little is known about the mechanisms of vascular effects of intravenous anesthetics. So we studied the effects of thiopental sodium, midazolam, propofol and ketamine on the endothelial nitric oxide-cGMP pathway and also on the membrane cyclooxygenase pathway. METHODS: After isolating ring strips of rat thoracic aorta, we measured the relaxation ED50 values of the four intravenous anesthetics from the maximally contracted using phenylephrine 10(-5)M. Then using L-NAME and methylene blue, we studied the effects of the drugs upon the NO-cGMP system. In addition, another pathway of vasodilation through membrane prostaglandin metabolism was examined using the membrane cyclooxygenase inhibitor, indomethacine. RESULTS: The following results were obtained. 1. Thiopental sodium (10(-5)M) did not have any effect on the PE induced contractions of aortic rings but midazolam (10(-6)M), propofol (10(-4)M) and ketamine (10(-3)M) significantly (P < 0.05) inhibited the PE induced contractions of aortic rings. 2. Midazolam 10(-6)M and propofol 10(-4)M induced relaxation of aortic rings were recovered with L-NAME pretreatment but ketamine induced relaxation was not recovered with L-NAME. 3. Midazolam 10(-6)M induced relaxation was not recovered with methylene blue pretreatment, but propofol 10(-4)M induced relaxation was recovered with methylene blue. 4. Indomethacine pretreatment induced further relaxation of midazolam or propofol induced relaxation of aortic rings. CONCLUSIONS: Midazolam, propofol and ketamine, but not thiopental sodium, relax rat thoracic aortic rings, and these relaxation effects of midazolam and propofol are endothelium dependent. Cyclooxygenase inhibition is related at least in part to midazolam or propofol induced relaxation, and guanylate cyclase to propofol induced relaxation.

The Comparison of Characteristics in Emergence between Inhalational Anesthesia Using Isoflurane and Total Intravenous Anesthesia Using Propofol and Ketamine / 대한마취과학회지

BACKGROUND: Total intravenous anesthesia (TIVA) is one of the anesthetic techniques that needs no inhalational agent but only an intravenous agent for induction and maintenance of anesthesia. Among drugs used in TIVA, propofol is the most popular agent. Rapid emergence and antiemetic characteristics of propofol are well known advantages but a dose dependent cardiovascular depressant effect is one of the disadvantages of this drug. Otherwise, ketamine, a dissociative agent, has been restricted in its use because of bad dreams, delirium and delayed emergence even though it has profound analgesic characteristics. However, ketamine has a stimulatory effect on the cardiovascular system, so it can raise blood pressure and pulse rate and in the case of TIVA, these properties can be advantageous when used with propofol. This study was aimed to decide whether TIVA using propofol and ketamine would have more stable vital signs during anesthesia and more rapid and smoother emergence in comparison with inhalational anesthesia using isoflurane. METHODS: Thirty two patients scheduled for elective general anesthesia were randomly allocated into two groups; I (inhalational anesthesia using isoflurane) group and PK (TIVA using propofol and ketamine) group. I group was controlled with isoflurane 1 - 1.5 vol% and the PK group was controlled with propofol 3 - 12 mg/kg/hr and ketamine 0.5 - 1.0 mg/kg/hr. Arriving at the recovery room, a single observer recorded the time to spontaneous movement, responses to painful pinch and verbal command, and orientation to age, name, place, date and time. At 5, 10, and 30 minutes after anesthesia, a PARS (postanesthesia recovery score), count-down test, and VAS (visual analogue scale) were checked. Postoperative events were checked in the recovery room and 24 hours lator. RESULTS: There was no significant difference in demographic data or characteristics of operation. Compared with the I group, the PK group had significantly rapid orientation responses on place, date and time. Restoration in the count-down test was more rapid in the PK group after 10 minutes in the recovery room. The VAS was lower in the PK group after 30 minutes in the recovery room. CONCLUSIONS: TIVA using propofol and ketamine has a more rapid emergence than inhalational anesthesia using isoflurane and better postoperative analgesic effect without respiratory depression.

Effect of supplemental intravenous anesthesia in plastic surgery under local anesthesia

When operations in the field of plastic surgery are performed under local anesthesia, the degree of pain suffering the patients becomes different depending on the kind, dosage effective duration of anesthetic agent and the technique of the operator. Patients suffer from pain physically and psychologically when skin infiltration is carried out. Recently, out-patient surgery has increased in number, so the necessity of more complete analgesia for the patient undergoing surgery is required. Patients were operated under the local infiltrative anesthesia, and the supplemental intravenous anesthesia to kill pain. Patients were randomly divided into four groups differing in combinations of intravenous anesthetic agents, such as ketamine, midazolam, fentanyl that have potent analgesic sedative and amnesic effects. By random allocation patients received ketamine and midazolam(Group I), ketamine and fentanyl(Group II), midazolam and fentany l (Group III), ketamine, fentanyl arts midazolam(Group IV). The purpose of this study is to focus on the results obtained in four groups for finding out a more safe and less complicated combination of intravenous anesthetic agents and for standardization of dosage. In conclusion the group I (ketamine and midazolam) showed better results than other groups for the following reasons; no significant change in vital signs, no hypoxia no complication such as nausea, headache unpleasant dream, and hallucination, potent analgesia effects, amnesia. We have found this combination to be a highly satisfactory anesthesia and analgesia technique for outpatient plastic surgery from the standpoints of the surgeon and the patient.

Effect of supplemental intravenous anesthesia in plastic surgery under local anesthesia

When operations in the field of plastic surgery are performed under local anesthesia, the degree of pain suffering the patients becomes different depending on the kind, dosage effective duration of anesthetic agent and the technique of the operator. Patients suffer from pain physically and psychologically when skin infiltration is carried out. Recently, out-patient surgery has increased in number, so the necessity of more complete analgesia for the patient undergoing surgery is required. Patients were operated under the local infiltrative anesthesia, and the supplemental intravenous anesthesia to kill pain. Patients were randomly divided into four groups differing in combinations of intravenous anesthetic agents, such as ketamine, midazolam, fentanyl that have potent analgesic sedative and amnesic effects. By random allocation patients received ketamine and midazolam(Group I), ketamine and fentanyl(Group II), midazolam and fentany l (Group III), ketamine, fentanyl arts midazolam(Group IV). The purpose of this study is to focus on the results obtained in four groups for finding out a more safe and less complicated combination of intravenous anesthetic agents and for standardization of dosage. In conclusion the group I (ketamine and midazolam) showed better results than other groups for the following reasons; no significant change in vital signs, no hypoxia no complication such as nausea, headache unpleasant dream, and hallucination, potent analgesia effects, amnesia. We have found this combination to be a highly satisfactory anesthesia and analgesia technique for outpatient plastic surgery from the standpoints of the surgeon and the patient.

Effect of Propofol on the Neuromuscular Transmission and Vecuronium-induced Muscle Relaxation / 대한마취과학회지

To investigate the effect of propofol in emulsion on the neuromuscular transmission and on the interaction with muscle relaxant, 31 adult parients, ASA I or II, were studied. Neuromuscular transmission was monitored continuously using a train-of-four(TOF) stimulation at every 20 seconds. The ulnar nerve was stimulated supramaximally through surface electrodes at a rate of 0.1 msec, 2Hz and the evoked compound action potential of hypothenar muscles was measured automatically with Relaxograph0atex). To determine the interaction of propofol with muscle relaxant, a bolus injection of propofol 2.5 mg/kg was given intravenously during a steady-state neuromuscular blockade of vencuronium and the effect on the twitch height measured for 30 minutes in 16 patients. To determine the action of propofol on neuromuscular transmission without muscle relaxant in 15 patients, propofol 20(n=7) or 40mg(n=8) in 10ml of 5% dextrose in water was injected respectively at isolated arm of which circulation was occluded by forearm pneumatic tourniquet and TOF response was measured for 10 minutes. In the results, propofol 2.5 mg/kg intravenous administration during steady-state neuromus- cular blokade of vecuronium did not show any change in the twitch height for 30 minutes. Propofol both 20 mg and 40 mg injected to isolated arm also did not show changes in first twitch height and train-of-four ratio for 10 minutes. Conclusively, propofol in emulsion does not interact with vecuronium at clinical dose, and also has not any effect on neuromuscular function at even high dose.

Effect of Propofol on the Neuromuscular Transmission and Vecuronium-induced Muscle Relaxation / 대한마취과학회지

To investigate the effect of propofol in emulsion on the neuromuscular transmission and on the interaction with muscle relaxant, 31 adult parients, ASA I or II, were studied. Neuromuscular transmission was monitored continuously using a train-of-four(TOF) stimulation at every 20 seconds. The ulnar nerve was stimulated supramaximally through surface electrodes at a rate of 0.1 msec, 2Hz and the evoked compound action potential of hypothenar muscles was measured automatically with Relaxograph0atex). To determine the interaction of propofol with muscle relaxant, a bolus injection of propofol 2.5 mg/kg was given intravenously during a steady-state neuromuscular blockade of vencuronium and the effect on the twitch height measured for 30 minutes in 16 patients. To determine the action of propofol on neuromuscular transmission without muscle relaxant in 15 patients, propofol 20(n=7) or 40mg(n=8) in 10ml of 5% dextrose in water was injected respectively at isolated arm of which circulation was occluded by forearm pneumatic tourniquet and TOF response was measured for 10 minutes. In the results, propofol 2.5 mg/kg intravenous administration during steady-state neuromus- cular blokade of vecuronium did not show any change in the twitch height for 30 minutes. Propofol both 20 mg and 40 mg injected to isolated arm also did not show changes in first twitch height and train-of-four ratio for 10 minutes. Conclusively, propofol in emulsion does not interact with vecuronium at clinical dose, and also has not any effect on neuromuscular function at even high dose.

Neuromuscular Blocking Effects of Ketamine / 대한마취과학회지

In the human isolated arm preparation applied tourniquet on the upper arm, the neuromuscular blocking effects of ketamine were confirmed with the changes of first twitch height (T1) and train of four ratio (T4R) induced from 2Hz ulnar nerve stimulation (ABM Datex Co.) at 20 minutes after administration of ketamine. The results obtained were as follows; In the control group administered of saline, T1 was elevated to 6.48% compared with before tourniquet applied but T4R was not changed through the whole of the process. In the group I administered of ketamine 1 mg/kg, T1 and T,R were depressed of 8.68% and 29.59% respectively but T1 was not significant. In the group II administered of ketamine 2 mg/kg, T1 and T4R were depressed of 43.4% and 40.4% respectively. T1 and T4R in the group I and II were significantly depressed comparing with control group.