Total intravenous anaesthesia techniques for ambulatory surgery

Belgian consensus guideline on the management of anal fissures

Introduction

Acute and chronic anal fissures are common proctological problems that lead to relatively high morbidity and frequent contacts with health care professionals. Multiple treatment options, both topical and surgical, are available, therefore evidence-based guidance is preferred.

Methods

A Delphi consensus process was used to review the literature and create relevant statements on the treatment of anal fissures. These statements were discussed and modulated until sufficient agreement was reached. These guidelines were based on the published literature up to January 2023.

Results

Anal fissures occur equally in both sexes, mostly between the second and fourth decades of life. Diagnosis can be made based on cardinal symptoms and clinical examination. In case of insufficient relief with conservative treatment options, pharmacological sphincter relaxation is preferred. After 6-8 weeks of topical treatment, surgical options can be explored. Both lateral internal sphincterotomy as well as fissurectomy are well-established surgical techniques, both with specific benefits and risks.

Conclusions

The current guidelines for the management of anal fissures include recommendations for the clinical evaluation of anal fissures, and their conservative, topical and surgical management.

Recovery Benefit With Total Intravenous Anesthesia in Patients Receiving Rhinoplasty

OBJECTIVE

The aim was to evaluate the difference in recovery when comparing total intravenous anesthesia (TIVA) to inhalational gas anesthesia in patients receiving rhinoplasty.

STUDY DESIGN

Retrospective review.

SETTING

Postoperative anesthesia care unit (PACU).

METHODS

Patients who received a functional or cosmetic rhinoplasty at a single academic institution between April 2017 and November 2020 were included. Inhalational gas anesthesia was in the form of sevoflurane. Phase I recovery time, which was defined as the time it took a patient to reach ≥9/10 on the Aldrete scoring system was recorded, as well as the usage of pain medication in the PACU. The postoperative course and incidence of postoperative nausea and vomiting (PONV) were also collected.

RESULTS

Two hundred and two patients were identified with 149 (73.76%) who received TIVA and 53 (26.24%) who received sevoflurane. For the patients who received TIVA, the average recovery time was 101.44 minutes (standard deviation [SD]: 34.64) compared to an average recovery time of 121.09 minutes (SD: 50.19) for patients who received sevoflurane leading to a difference of 19.65 minutes (p = 0.002). Patients who received TIVA experienced less PONV (p = 0.001). There were no differences in the postoperative course including surgical or anesthesia complications, postoperative complications, hospital or Emergency Department admissions, or administration of pain medication (p > 0.05 for all).

CONCLUSION

When utilizing TIVA over inhalational anesthesia, patients undergoing rhinoplasty had significantly increased benefits in terms of reduced phase I recovery times and decreased incidence of PONV. TIVA was demonstrated to be a safe and efficacious method of anesthesia for this patient population.

Total Intravenous Anesthesia Versus Inhaled Sevoflurane in Obstructive Sleep Apnea Surgery: A Randomized Controlled Trial

OBJECTIVE

Specific guidelines regarding an optimal general anesthesia (GA) approach to obstructive sleep apnea (OSA) patients remain undefined. Literature comparing the efficacy of total intravenous anesthesia (TIVA) and inhalational anesthesia in this population is sparse. We hypothesize that OSA patients receiving TIVA will experience reduced recovery times and other improved post-surgical outcomes.

STUDY DESIGN

Randomized controlled trial.

METHODS

Adult OSA patients undergoing upper airway surgery (hypoglossal nerve stimulation [HNS], nasal, or palate surgery) from February 2020-December 2020 were included. A post-anesthesia care unit (PACU) nursing survey documented patients' alertness, pain, oxygen supplementation, and postoperative nausea and vomiting from PACU arrival to 2 hours. Perioperative timepoints from the electronic medical record (EMR) and a nurse-estimated Phase I recovery time were collected.

RESULTS

One hundred eleven patients were included (46 TIVA and 65 inhalational anesthesia). Per EMR-recorded timepoints, TIVA patients undergoing HNS and palate surgery experienced Phase I Time reductions of 12.5 min (p = 0.042) and 27.5 min (p = 0.016), respectively. Per the PACU survey, TIVA patients undergoing any surgery, HNS, or palate surgery experienced nurse-estimated Phase I Time reductions of 16.5 min (p = 0.004), 12.5 min (p = 0.031), and 38.5 min (p = 0.024), respectively. Overall, TIVA patients experienced higher alertness and pain ratings, and lower oxygen supplementation requirements from PACU arrival to 30 min (p < 0.05).

CONCLUSION

Patients with OSA receiving TIVA for GA maintenance during upper airway procedures experienced reduced recovery times and oxygen supplementation requirements, and a more rapid return to alertness. Future work toward developing optimized anesthetic guidelines for OSA patients is merited.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:984-992, 2023.

Epidural and subdural hematoma following spinal anesthesia in infants rat model

The aim of this study was to assess the epidural and subdural hematoma following spinal anesthesia in infants' rat model. We investigated during 10, 15, and 20 days' rats in group 1: intrathecal injection of bupivacaine 3.75 mg/kg (n = 7); group 2: received 37.5 μl midazolam 0.1% intrathecal with 37.5μl fentanyl 0.005% (no=7); injected into group 3 methylene blue 1 mg/ml (No. 7). Rats were exposed to spinal anesthesia in infancy and rotarod in motor function in adulthood. Histological evaluation and tissue extraction were also performed after the treatment and magnetic resonance imaging (MRI) of the head. MRI of the head of all rat pups that showed similar symptoms were performed. 4 rat pups showed the symptoms of hematoma Group1: small acute subdural hematoma at the left posterior temporal-parietal junction (PTPJ) and group 2 (one: right temporal epidural hematoma, two: Small acute subdural hematoma in the right temporomandibular area, and three: frontal-temporal-parietal-occipital hematoma). the rat pup that had epidural hematoma died 6 hours later. Finally, in the first group, one rat and the second group three rats showed hematoma symptoms. For these three rats, a histopathologic study was performed and indicate the presence of small acute subdural hematoma at the left posterior temporal-parietal junction, right temporal epidural hematoma, and frontal-temporal-parietal-occipital hematoma. In summary, because subdural or epidural hematoma of the skull can have serious consequences, differential diagnosis is very important for pain after spinal anesthesia.

Effect of additional equipotent fentanyl or sufentanil administration on recovery profiles during propofol-remifentanil-based anaesthesia in patients undergoing gynaecologic laparoscopic surgery: a randomized clinical trial

Background

In clinical practice, sufentanil has a stronger sedative effect on patients than fentanyl at equivalent doses. This study hypothesized that, at equivalent doses, patients undergoing gynaecologic laparoscopic surgery (GLS) receiving fentanyl would have an earlier emergence from anaesthesia (EA), a shorter time to extubation (TE), and a better degree of wakefulness. Therefore, this study evaluated the effects of equipotent doses of fentanyl and sufentanil on the quality of emergence in patients undergoing GLS.

Methods

One hundred seven patients scheduled for GLS under general anaesthesia were randomly divided into two groups and were induced with 0.35 µg/kg sufentanil (Group S; n = 55) or 3.5 µg/kg fentanyl (Group F; n = 52). When the GLS was almost over, the patient's abdominal cavity was flushed with warm saline, and 5 µg of sufentanil or 50 µg of fentanyl in a double-blind manner was intravenously injected into the patients. The primary outcomes of the study included EA, TE, the rate of leaving the surgical bed voluntarily and the incidence of endotracheal tube tolerance. The Ramsay Sedation Scale (RSS), and Verbal Rating Scale (VRS) scores at 15 and 30 min in the postanaesthesia care unit (PACU), as well as other adverse events, including nausea and vomiting, itching, delirium, dizziness, chills, and respiratory depression (SpO₂ < 95%) in the PACU, were evaluated as secondary outcomes.

Results

There were no statistically significant dissimilarities between the two groups with respect to baseline characteristics. For recovery, the EA (9.0 ± 4.8 min vs. 8.9 ± 3.0 min; P = 0. 146), TE (9.5 ± 4.7 min vs. 9.0 ± 3.0 min; P = 0.135), rate of leaving the surgical bed voluntarily (31.18% vs. 38.46%; P = 0.976), and incidence of endotracheal tube tolerance (94.55% vs. 96.15%; P = 0.694) were not significantly different between the two groups. In the PACU, the 15-min RSS score (2.07 ± 0.38 vs. 2.15 ± 0.36; P = 0.125), the 30-min RSS score (2.02 ± 0.13 vs. 2.04 ± 0.19; P = 0.207), the 15-min VRS score (0.50 ± 0.57 vs. 0.67 ± 0.55; P = 0.295), and the 30-min VRS score (0.45 ± 0.50 vs. 0.75 ± 0.52; P = 0.102) were not significantly different between Groups S and F. No adverse events, such as nausea, vomiting, pruritus, delirium, and tremors, occurred in either group. The rates of respiratory depression (1.82% vs. 1.92%; P = 0.968) and dizziness (0.00% vs. 4.85%; P = 0.142) were not different between Groups S and F in the PACU.

Conclusions

The majority of patients scheduled for GLS were able to rapidly and smoothly emerge from anaesthesia. After surgery, similar outcomes, including EA, TE, the incidence of endotracheal tube tolerance, the rate of leaving the surgical bed voluntarily, RSS scores, VRS scores, and adverse events in the PACU, were achieved for the patients between the two anaesthetic protocols.

Saddle block anesthetic technique for benign outpatient anorectal surgery

BACKGROUND

Current American Society of Colorectal Surgery Clinical Practice Guidelines for Ambulatory Anorectal Surgery endorse use of monitored anesthesia care, general anesthesia, or spinal anesthesia based on physician and patient preference. Although several studies support the use of monitored anesthesia care over general anesthesia, the literature regarding spinal anesthesia is limited and heterogenous due to small sample sizes and disparate spinal anesthesia techniques. Saddle block anesthesia is a form of spinal anesthesia that localizes to the lowermost sacral spinal segments allowing for preservation of lower extremity motor function and faster recovery. We accrued one of the largest reported cohort of anorectal procedures using saddle block anesthesia, as such, we sought to evaluate our institutional 12-year experience.

METHODS

Patients who underwent a benign anorectal procedure at our outpatient surgery center between July 2008-2020 were retrospectively reviewed. Demographics, surgical factors, perioperative times, and adverse events were collected from the electronic medical records. Saddle block anesthesia was generally performed in the preoperative area using a spinal needle (25-27 gauge) and a single injection technique of a 1:1 ratio local anesthetic mixed with 10% dextrose solution. Between 2.5-5 mg of hyperbaric anesthetic was injected intrathecally in the sitting position and the patient remained upright for 3-10 minutes. This technique of saddle block anesthesia provides analgesia for approximately 1-3 hours.

RESULTS

In the study, 859 saddle block anesthesia patients were identified, with a mean age of 44.6 years and American Society of Anesthesia score of 1.9; 609 (70.9%) were male. Surgical indications included lesion removal (27.1%), anal fistula (25.8%), hemorrhoidectomy (24.7%), pilonidal disease (6.3%), anal fissure (5.8%), and a combination of prior (10.2%). Prone jackknife positioning was used in 91.6% of procedures. Saddle block anesthesia most often was performed with bupivacaine (48.9%) or ropivacaine (41.7%). The median procedural saddle block anesthesia time was 11 minutes, surgery time was 17 minutes, anesthesia time was 42 minutes, and recovery time was 91 minutes. Patients spent a median of 3 hours and 53 minutes in the facility. Adverse events included urinary retention (1.9%), conversion to general anesthesia (1.8%), spinal headache (1.5%), hemodynamic instability (0.9%), and injection site reaction (0.3%).

CONCLUSION

Demonstrated using the largest known cohort of anorectal patients with saddle block anesthesia, saddle block anesthesia provides an effective method of analgesia to avoid general anesthesia with a low rate of adverse events.

Outpatient Percutaneous Endovascular Abdominal Aortic Aneurysm Repair: A Single-Center Experience

PURPOSE

To evaluate the safety of outpatient percutaneous endovascular abdominal aortic repair (PEVAR) versus inpatient PEVAR without or with adjunct procedures.

MATERIALS AND METHODS

Between January 2012 and June 2019, a cohort of 359 patients comprising 168 (46.8%) outpatients and 191 (53.2%) inpatients who had undergone PEVAR were enrolled. All the patients were asymptomatic but had indications for endovascular aortic repair, ie, fit for intravenous anesthesia and anatomically feasible with standard devices. Patient sex, age, comorbidities, smoking status, type of anesthesia, adjunct procedures, type of graft device, operative times, mortality, complications, and readmissions were analyzed.

RESULTS

Median follow-up period was 16.5 months (interquartile range, 9-31 months). Except for a higher percentage of tobacco use (42.6% vs 28.8%; P = .04), dyslipidemia (39.7% vs 19.2%; P < .01), and use of local anesthesia (99.4% vs 82.2%; P < .01) in the outpatients, there was no significant difference in the type of graft and adjunct procedures used. No outpatient mortality occurred. There was no difference in the number, severity, and onset of complications (all P > .05). Outpatient unexpected same-day admission, 30-day readmission, and emergency department visit rates were 4.8%, 2.4% (P = .13), and 10% (P < .01), respectively. Operative times for outpatient PEVAR without adjunct procedures were shorter (P < .01).

CONCLUSIONS

Outpatient PEVAR can be performed with a safety profile similar to that of inpatient PEVAR. The unexpected same-day admission, 30-day readmission, and emergency department visit rates were low. The outpatient PEVARs without adjunct procedures took less time.

Does Total Intravenous Anesthesia With Short-acting Spinal Anesthetics in Primary Hip and Knee Arthroplasty Facilitate Early Hospital Discharge?

INTRODUCTION

Our study assessed the effect of total intravenous anesthesia (TIVA) with short-acting spinal anesthesia and aggressive day-of-surgery postoperative day 0 physical therapy (POD#0 PT) on hospital length of stay (LOS) in patients who underwent primary total joint arthroplasty.

METHODS

A retrospective chart review compared the hospital LOS of 116 patients who underwent primary total hip arthroplasty and total knee arthroplasty with TIVA and short-acting spinal blockade ("Updated protocol group") with that of the control group of 228 patients who were under standard anesthesia ("Traditional protocol group").

RESULTS

Both total hip arthroplasty and total knee arthroplasty patients in the Updated protocol group had markedly reduced LOS compared with those in the Traditional protocol group (1.5 ± 0.1 days versus 2.4 ± 0.1 days; P < 0.05 and 1.4 ± 0.1 days versus 2.3 ± 0.1 days; P < 0.05). A higher proportion of patients in the Updated protocol group received at least 1 POD#0 PT session compared with those in the Traditional protocol group.

CONCLUSION

Total intravenous anesthesia combined with short-acting spinal anesthetics provided the following benefits for patients who underwent primary total joint arthroplasty: more day-of-surgery PT sessions and earlier discharge by nearly 1 full day.

LEVEL OF EVIDENCE

III.

The influence of norepinephrine and phenylephrine on cerebral perfusion and oxygenation during propofol-remifentanil and propofol-remifentanil-dexmedetomidine anaesthesia in piglets

Background

Vasopressors are frequently used to increase blood pressure in order to ensure sufficient cerebral perfusion and oxygenation (CPO) during hypotensive periods in anaesthetized patients. Efficacy depends both on the vasopressor and anaesthetic protocol used. Propofol–remifentanil total intravenous anaesthesia (TIVA) is common in human anaesthesia, and dexmedetomidine is increasingly used as adjuvant to facilitate better haemodynamic stability and analgesia. Little is known of its interaction with vasopressors and subsequent effects on CPO. This study investigates the CPO response to infusions of norepinephrine and phenylephrine in piglets during propofol–remifentanil and propofol–remifentanil–dexmedetomidine anaesthesia. Sixteen healthy female piglets (25–34 kg) were randomly allocated into a two-arm parallel group design with either normal blood pressure (NBP) or induced low blood pressure (LBP). Anaesthesia was induced with propofol without premedication and maintained with propofol–remifentanil TIVA, and finally supplemented with continuous infusion of dexmedetomidine. Norepinephrine and phenylephrine were infused in consecutive intervention periods before and after addition of dexmedetomidine. Cerebral perfusion measured by laser speckle contrast imaging was related to cerebral oxygenation as measured by an intracerebral Licox probe (partial pressure of oxygen) and transcranial near infrared spectroscopy technology (NIRS) (cerebral oxygen saturation).

Results

During propofol–remifentanil anaesthesia, increases in blood pressure by norepinephrine and phenylephrine did not change cerebral perfusion significantly, but cerebral partial pressure of oxygen (Licox) increased following vasopressors in both groups and increases following norepinephrine were significant (NBP: P = 0.04, LBP: P = 0.02). In contrast, cerebral oxygen saturation (NIRS) fell significantly in NBP following phenylephrine (P = 0.003), and following both norepinephrine (P = 0.02) and phenylephrine (P = 0.002) in LBP. Blood pressure increase by both norepinephrine and phenylephrine during propofol–remifentanil–dexmedetomidine anaesthesia was not followed by significant changes in cerebral perfusion. Licox measures increased significantly following both vasopressors in both groups, whereas the decreases in NIRS measures were only significant in the NBP group.

Conclusions

Cerebral partial pressure of oxygen measured by Licox increased significantly in concert with the vasopressor induced increases in blood pressure in healthy piglets with both normal and low blood pressure. Cerebral oxygenation assessed by intracerebral Licox and transcranial NIRS showed opposing results to vasopressor infusions.

Electronic supplementary material

The online version of this article (10.1186/s13028-018-0362-z) contains supplementary material, which is available to authorized users.

The effect of dexmedetomidine on cerebral perfusion and oxygenation in healthy piglets with normal and lowered blood pressure anaesthetized with propofol-remifentanil total intravenous anaesthesia

BACKGROUND

During anaesthesia and surgery, in particular neurosurgery, preservation of cerebral perfusion and oxygenation (CPO) is essential for normal postoperative brain function. The isolated effects on CPO of either individual anaesthetic drugs or entire anaesthetic protocols are of importance in both clinical and research settings. Total intravenous anaesthesia (TIVA) with propofol and remifentanil is widely used in human neuroanaesthesia. In addition, dexmedetomidine is receiving increasing attention as an anaesthetic adjuvant in neurosurgical, intensive care, and paediatric patients. Despite the extensive use of pigs as animal models in neuroscience and the increasing use of both propofol-remifentanil and dexmedetomidine, very little is known about their combined effect on CPO in pigs with uninjured brains. This study investigates the effect of dexmedetomidine on CPO in piglets with normal and lowered blood pressure during background anaesthesia with propofol-remifentanil TIVA. Sixteen healthy female Danish pigs (crossbreeds of Danish Landrace, Yorkshire and Duroc, 25-34 kg) were used. Three animals were subsequently excluded. The animals were randomly allocated into one of two groups with either normal blood pressure (NBP, n = 6) or with induced low blood pressure (LBP, n = 7). Both groups were subjected to the same experimental protocol. Intravenous propofol induction was performed without premedication. Anaesthesia was maintained with propofol-remifentanil TIVA, and later supplemented with continuous infusion of dexmedetomidine. Assessments of cerebral perfusion obtained by laser speckle contrast imaging (LSCI) were related to cerebral oxygenation measures (PbrO2) obtained by an intracerebral Clark-type Licox probe.

RESULTS

Addition of dexmedetomidine resulted in a 32% reduction in median PbrO2 values for the LBP group (P = 0.03), but no significant changes in PbrO2 were observed for the NBP group. No significant changes in LSCI readings were observed in either group between any time points, despite a 28% decrease in the LBP group following dexmedetomidine administration. Caval block resulted in a significant (P = 0.02) reduction in median MAP from 68 mmHg (range 63-85) at PCB to 58 mmHg (range 53-63) in the LBP group, but no significant differences in either PbrO2 or LSCI were observed due to this intervention (P = 0.6 and P = 0.3 respectively).

CONCLUSIONS

Addition of dexmedetomidine to propofol-remifentanil TIVA resulted in a significant decrease in cerebral oxygenation (PbrO2) measurements in piglets with lowered blood pressure. Cerebral perfusion (LSCI) did not decrease significantly in this group. In piglets with normal blood pressure, no significant changes in cerebral perfusion or oxygenation were seen in response to addition of dexmedetomidine to the background anaesthesia.

Sevoflurane at 1.0 MAC together with remifentanil and propofol produces clinically acceptable intubation conditions at the vocal cords: A prospective randomized study

Objective

The overall intubation conditions after tracheal intubation with remifentanil, propofol, and sevoflurane at 1.0 minimum alveolar concentration (MAC) are worse than with rocuronium at 0.45 mg/kg. Therefore, we compared the intubation conditions and laryngeal morbidity (vocal cord injuries, hoarseness, and sore throat) with sevoflurane at 1.2 and 1.4 MAC versus 1.0 MAC.

Methods

In this prospective clinical trial, 90 patients were randomized to 3 groups: the sevoflurane 1.0, 1.2, and 1.4 MAC groups. At 3 min, tracheal intubation was performed and the patients’ intubation conditions were assessed. The vocal cords were examined for injury by videolaryngoscopy. Additionally, the incidence and severity of laryngeal morbidity were compared between women and men.

Results

Acceptable intubation conditions were seen in 72% of the patients without significant differences between the groups. Overall, vocal cord injuries (oedema) occurred in three (4%) patients. Women reported sore throat more often than men (51% vs. 21%, respectively).

Conclusions

Intubation conditions were not improved with higher sevoflurane concentrations. The incidence and severity of sore throat were greater in women than men.

Trial registration: ClinicalTrials.Gov: NCT 01896245

Effect of desflurane-remifentanil vs. Propofol-remifentanil anesthesia on arterial oxygenation during one-lung ventilation for thoracoscopic surgery: a prospective randomized trial

BACKGROUND

One-lung ventilation during thoracic surgery frequently disturbs normal systemic oxygenation. However, the effect of anesthetics on arterial oxygenation during one-lung ventilation has not been well established in human study. In this clinical trial, we investigated whether a difference between desflurane-remifentanil and propofol-remifentanil anesthesia can be observed with regard to oxygenation during one-lung ventilation for thoracoscopic surgery.

METHODS

Adult patients with lung cancer, scheduled for video-assisted thoracoscopic lobectomy without preoperative oxygen support, were screened and randomized to receive desflurane or propofol, with remifentanil continuous infusion in both groups. Mechanical ventilation was performed with tidal volume of 8 ml/kg and F_IO₂ 0.5 during two-lung ventilation, and 6 ml/kg and 1.0 during one-lung ventilation, both with positive end-expiratory pressure of 5 cmH₂O. Arterial blood gas analysis was performed preoperatively, during two-lung ventilation, and after 15, 30, 45, and 60 min of one-lung ventilation. The primary endpoint was PaO₂ at 30 min after initiating one-lung ventilation. Statistical analyses included the independent t-test for the primary endpoint and a mixed model with a post-hoc analysis to evaluate the serial changes in values.

RESULTS

Patients were recruited between July 9 and December 2, 2014. In total, 103 patients were analyzed (n = 52 in desflurane group and n = 51 in propofol group). The primary endpoint, PaO₂ at 30 min of one-lung ventilation was lower in the desflurane group than the propofol group (170 ± 72 vs. 202 ± 82 mmHg; p = 0.039). Serial changes in PaO₂ during one-lung ventilation showed lower levels during desflurane anesthesia compared with propofol anesthesia (mean difference, 45 mmHg; 95% confidence interval, 16-75 mmHg; p = 0.003).

CONCLUSIONS

In conclusion, desflurane-remifentanil anesthesia resulted in decreased arterial oxygenation compared with that of propofol-remifentanil anesthesia during one-lung ventilation for thoracoscopic surgery in patients with lung cancer.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02191371 , registered on July 7, 2014.

Incidence of postoperative nausea and vomiting following gynecological laparoscopy: A comparison of standard anesthetic technique and propofol infusion

OBJECTIVE

To determine the safety, efficacy, and feasibility of propofol-based anesthesia in gynecological laparoscopies in reducing incidences of postoperative nausea and vomiting compared to a standard anesthesia using thiopentone/isoflurane.

DESIGN

Randomized single-blind (for anesthesia techniques used) and double-blind (for postoperative assessment) controlled trial.

SETTING

Operation theater, postanesthesia recovery room, teaching hospital.

PATIENTS

Sixty ASA (American Society of Anesthesiologists) I and II female patients (aged 20-60 years) scheduled for gynecological laparoscopy were included in the study.

INTERVENTIONS

Patients in Group A received standard anesthesia with thiopentone for induction and maintenance with isoflurane-fentanyl, and those in Group B received propofol for induction and maintenance along with fentanyl. All patients received nitrous oxide, vecuronium, and neostigmine/glycopyrrolate. No patient received elective preemptive antiemetic, but patients did receive it after more than one episode of vomiting.

MEASUREMENTS

Assessment for incidence of postoperative nausea and vomiting as well as other recovery parameters were carried out over a period of 24 hours.

MAIN RESULTS

Six patients (20%) in Group A and seven patients (23.3%) in Group B experienced nausea. Two patients (6.66%) in Group B had vomiting versus 12 (40%) in Group A (p<0.05). Overall, the incidence of emesis was 60% and 30% in Groups A and B, respectively (p<0.05). All patients in Group B had significantly faster recovery compared with those in Group A. No patient had any overt cardiorespiratory complications.

CONCLUSION

Propofol-based anesthesia was associated with significantly less postoperative vomiting and faster recovery compared to standard anesthesia in patients undergoing gynecological laparoscopy.

Effect of propofol and remifentanil on cerebral perfusion and oxygenation in pigs: a systematic review

The objective of this review is to evaluate the existing literature with regard to the influence of propofol and remifentanil total intravenous anaesthesia (TIVA) on cerebral perfusion and oxygenation in healthy pigs. Anaesthesia has influence on cerebral haemodynamics and it is important not only in human but also in veterinary anaesthesia to preserve optimal regulation of cerebral haemodynamics. Propofol and remifentanil are widely used in neuroanaesthesia and are increasingly used in experimental animal studies. In translational models, the pig has advantages compared to small laboratory animals because of brain anatomy, metabolism, neurophysiological maturation, and cerebral haemodynamics. However, reported effects of propofol and remifentanil on cerebral perfusion and oxygenation in pigs have not been reviewed. An electronic search identified 99 articles in English. Title and abstract screening selected 29 articles for full-text evaluation of which 19 were excluded with reasons. Of the 10 peer-reviewed articles included for review, only three had propofol or remifentanil anaesthesia as the primary study objective and only two directly investigated the effect of anaesthesia on cerebral perfusion and oxygenation (CPO). The evidence evaluated in this systematic review is limited, not focused on propofol and remifentanil and possibly influenced by factors of potential importance for CPO assessment. In one study of healthy pigs, CPO measures were within normal ranges following propofol-remifentanil anaesthesia, and addition of a single remifentanil bolus did not affect regional cerebral oxygen saturation (rSO2). Even though the pool of evidence suggests that propofol and remifentanil alone or in combination have limited effects on CPO in healthy pigs, confirmative evidence is lacking.

Monitored anesthesia care for great saphenous vein stripping surgery with target controlled infusion of propofol and remifentanil: a prospective study

Background

The aim of this study was to determine the appropriate target concentrations at the effect site of propofol and remifentanil when deep sedation was achieved by monitored anesthesia care (MAC) anesthesia and related respiratory depression during vein stripping surgery for varicose veins.

Methods

In total, 51 adult patients who were scheduled for varicose vein stripping surgery were sedated with propofol and remifentanil during the surgery, after administration of midazolam. Target concentrations at the effect site of the two drugs were changed based on the patient's status. Respiratory support was applied in the order of oxygen supply, chin lift, and assisted mask ventilation. Target concentrations at the effect site of propofol and remifentanil, the need for respiratory support, and a six-point rating scale satisfaction score were the outcome measurements.

Results

Only one patient did not require oxygen, eight patients needed oxygen alone, 22 patients required use of the chin lift technique, and 20 patients were assisted with mask ventilation. There was no significant difference in the target concentration of propofol or remifentanil between the patients who required mask ventilation and those who did not. Fifty of the 51 patients reported a satisfaction score of 6.

Conclusions

Although MAC using low target concentrations of propofol and remifentanil during vein stripping surgery was satisfactory to patients, close observation regarding the need for respiratory assistance was necessary.

Effects of µ-Opioid Receptor Gene Polymorphism on Postoperative Nausea and Vomiting in Patients Undergoing General Anesthesia with Remifentanil: Double Blinded Randomized Trial

Association between postoperative nausea and vomiting (PONV) and µ-opioid receptor A118G single nucleotide polymorphism (SNP) is undefined and might underlie inconsistent results of studies on PONV occurrence in patients undergoing general anesthesia with the opioid, remifentanil. Four hundred and sixteen Korean women undergoing breast surgery with general anesthesia were randomized to receive remifentanil 10 ng/mL (plasma-site, Minto model) using a target-controlled infusion device and either propofol for total intravenous anesthesia (T group) or sevoflurane for inhalation anesthesia (I group) with bispectral index values maintained between 40 and 60. Blood specimens were collected after anesthesia induction for A118G SNP analysis. PONV and postoperative pain were evaluated. A118G SNP type distribution among Korean female adults studied was AG (n=195)>AA (n=158)>GG (n=63). Regardless of anesthetic technique, patients with GG types had lower PONV scale on arrival at postoperative care unit (PACU) (P=0.002), while T group showed lower PONV scale than I group up to 6 hr after PACU discharge in AA and AG types. No differences were apparent for postoperative pain among opioid receptor polymorphism. PONV occurrence differs according to opioid receptor polymorphism and anesthetic technique in patients undergoing general anesthesia with remifentanil.

An analysis of anesthesia-controlled operating room time after propofol-based total intravenous anesthesia compared with desflurane anesthesia in ophthalmic surgery: a retrospective study

BACKGROUND

Anesthetic techniques can contribute to reduction of anesthesia-controlled time to improve operating room (OR) efficiency. However, little is known about the difference in anesthesia-controlled time between propofol-based total IV anesthesia (TIVA) and desflurane anesthesia (DES) techniques for ophthalmic surgery under general anesthesia.

METHODS

We performed a retrospective analysis using hospital databases to compare the anesthesia-controlled times of ophthalmic surgery patients receiving either TIVA via target-controlled infusion with propofol/fentanyl or desflurane/fentanyl-based anesthesia between January 2010 and December 2011. The various time intervals (surgical time, incision to surgical completion and application of dressings; anesthesia time, start of anesthesia to extubation; extubation time, surgery complete and dressings applied to extubation; time in OR, arrival in the OR to departure from the OR; postanesthetic care unit (PACU) stay time, arrival in the PACU to discharge from the PACU to the general ward; and total surgical suite time, arrival in the OR to discharge from the PACU to the general ward) that comprise a patient's hospital stay and the incidence of postoperative nausea and vomiting were compared between the 2 anesthetic techniques.

RESULTS

We included data from 1405 patients, with 595 patients receiving TIVA and 810 receiving DES. The extubation time was faster (TIVA-DES = -1.85 minutes, 99.2% confidence interval [CI], -2.47 to -1.23 minutes) and the PACU stay time was shorter (TIVA-DES = -3.62 minutes, 99.2% CI, -6.97 to -0.10 minutes) in the TIVA group than in the DES group. However, there was no significant difference in total surgical suite time between groups (TIVA-DES = -5.03 minutes, 99.2% CI, -11.75 to 1.69 minutes). We performed the random-effects analyses while stratifying for procedure and showed that the extubation time in the TIVA group was faster by 14% (99.2% CI, 9% to 19%, P < 0.0001) relative to the DES group, and the PACU stay time was faster by 5% (99.2% CI, 1% to 10%, P = 0.002). Significantly fewer patients suffered postoperative nausea and vomiting and required rescue therapy in the TIVA group than in the DES group (11.3% vs 32.2%, risk difference 21.0%, 95% CI, 16.9% to 25.1%, P < 0.001 and 23.9% vs 54.0%, risk difference 30.1%, 95% CI, 18.3% to 42.0%, P = 0.002, respectively).

CONCLUSIONS

In our hospital, the use of TIVA reduced the mean time to extubation by at least 9% and PACU stay time by more than 1% when compared with the use of DES anesthesia for ophthalmic surgery.

Development of a system for the automatic detection of air embolism using a precordial Doppler

Venous air embolism (VAE) is the air bubble accumulation in the right side of the heart. Changes in Doppler heart sound (DHS) are characteristic of VAE, and the anesthesiologist has to pay attention to this event continuously, which may not always be possible. This work aims to study different features of the heart sound through a precordial Doppler, that may provide useful information on VAE episodes. A clinical protocol was designed, and DHS was collected at baseline and following infusions of saline with 4 distinct volumes (1ml, 5ml, 8ml and 10ml), and two infusion rates (slow and fast), given by central and peripheric catheters. Signal was pre-processed, the envelope of each signal was extracted, and five features were implemented and evaluated: frequency corresponding to 95% of Welch periodogram power (f95), frequency corresponding to 50% of Welch periodogram power (f50), frequency corresponding to maximum power spectral density (fm), entropy (E), and frequency corresponding to maximum energy of a wavelet transform (freqwav). Relation between extracted features and saline infusions were studied and compared to baseline values. A Graphical User Interface (GUI) with a database of Doppler heart sounds and annotations was also developed. Although features present a high variability between patients, E presents a better performance showing an increase in response to saline injections (in 75% injections), followed by f95 (62%), fm (56.3%), freqwav (37.5%) and f50 (0%).

Comparison of Two Clinical Protocols for Total Intravenous Anesthesia (TIVA) for Breast Surgery Using Propofol Combined With Either Sufentanil or Alfentanil

BACKGROUND

Sufentanil and alfentanil have pharmacokinetic and dynamic properties which make them favourable substances for total intravenous anesthesia (TIVA) in combination with propofol.

OBJECTIVES

We planned to compare two clinical protocols for TIVA with propofol, and either sufentanil or alfentanil in regards to postoperative pain, hemodynamic stability during the case and time for emergence from anesthesia.

PATINETS AND METHODS

Treaty eight patients scheduled for general anesthesia for breast surgery were included in this Double-blind, randomized, controlled trial. All patients received a standardized TIVA with propofol and either 0.2 µg kg(-1) sufentanil or 20 µg kg(-1) alfentanil for induction and 0.3 µg kg(-1) h(-1) sufentanil or 30 µg kg(-1) h(-1) alfentanil for maintenance with additional propofol boluses as needed. During anesthesia, heart rate, non-invasive blood-pressure, peripheral oxygen saturation and depth of anesthesia, were recorded. In the post anesthesia care unit, pain scores, nausea and vomiting as well as medications were recorded.

RESULTS

Patients in the sufentanil group required less often additional opioid and propofol boluses to maintain adequate anesthesia. We did not observe a significant difference in time to extubation. Postoperatively, patients in the sufentanil group had less pain (P = 0.03) and required less i.v. opioids (0.4 vs. 1.9 mg piritramid, P = 0.04).

CONCLUSIONS

Both protocols provide excellent anesthesia, but patients receiving sufentnail had more stable anesthesia and less postoperative pain.

[General anesthesia for ambulatory surgery : Clinical pharmacological considerations on the practical approach]

Due to modern surgical and anesthesia techniques, many patients undergoing small or even medium surgical procedures will recover within minutes and can then be discharged after a few hours of monitoring. Aside from an optimized surgical technique, a precise and differentiated anesthesia concept is needed to guarantee rapid recovery and home readiness. Nowadays, remifentanil-propofol represents the standard regime in ambulatory anesthesia. The use of alfentanil, desfluran or sevofluran is also possible whereas other intravenous or inhaled anesthetics or other opioids are rarely used. If endotracheal intubation is necessary, a reduced intubating dose of neuromuscular blockers (NMB), such as mivacurium, atracurium and rocuronium, i.e. 1-1.5-times the 95 % effective dose (ED95) is a good possibility to accelerate neuromuscular recovery while still having acceptable intubation conditions. Due to its limitations and contraindications, succinylcholine is not the first choice but may be used in non-fasting patients in need of urgent (ambulatory) surgery, e.g. in bleeding women undergoing dilation and curettage. Even with these reduced dosages monitoring of neuromuscular recovery is crucial and should be applied to all patients when NMBs are used. Furthermore, patients should receive a risk-adapted postoperative nausea and vomiting (PONV) prophylaxis, e.g. with 4 mg dexamethasone and 4 mg ondansetron. Postdischarge nausea and vomiting (PDNV) should be anticipated by a new risk score and prophylaxis or treatment should be initiated. For postoperative pain relief, local or regional anesthesia techniques, such as infiltration, field or nerve blocks should be applied where possible. In addition, non-opioid analgesics are the basic treatment while longer-lasting opioids are only necessary for some patients.

Novel and effective balanced intravenous-inhalant anaesthetic protocol in swine by using unrestricted drugs

Nowadays, because of increasing employment of swine for experimental studies and medical training, it is hopeful to investigate novel and effective anaesthetic protocols for preserving the animal welfare in medical investigation and concurrently improving the quality of research. Therefore, the aim of this study was to investigate a novel and effective anaesthetic protocol in swine undergoing major surgery, by translating know-how of combined anaesthesia from human protocols. Seven landrace swine were anaesthetized for three hours by a combined trial anaesthetic protocol (sedation: medetomidine, acepromazine, atropine and tramadol; induction: propofol, medetomidine and acepromazine; anaesthesia: isofluorane, propofol, medetomidine and acepromazine) and both clinical and haemodynamic parameters were compared with those of five swine anaesthetized with a control protocol (sedation: diazepam, ketamine and atropina; induction: diazepam and ketamine; anaesthesia: isofluorane). Both cardiac frequency (CF) and mean blood pressure (MBP) were significantly (P<0.05) more stable in trial protocol (CF: 78.3 ± 4.6-81.1 ± 5, MBP: 63.9 ± 10.7-96.4 ± 13.0) compared to control protocol (CF: 93.7 ± 5.5-102.5 ± 8.5, MBP: 71.0 ± 6.6-108.7 ± 7.2). The body temperature remained stable in trial protocol (°C: 36.9 ± 0.7-37.2 ± 0.3) compared to control anaesthesia (°C: 36.4 ± 0.3-37.3 ± 0.2, P<0.05). Haematosis improved undergoing combined anaesthesia (+2%, P<0.05) whereas did not change in control animals. There were no differences in respiratory rate between trial and control protocols. This study demonstrates that the proposed balanced intravenous-inhalant protocol permits to carry out a very effective, stable and safe anaesthesia in swine undergoing deep anaesthesia.

Hemodynamic and biochemical changes in liver transplantation: A retrospective comparison of desflurane and total intravenous anesthesia by target-controlled infusion under auditory evoked potential guide

OBJECTIVES

Propofol-based total intravenous anesthesia (TIVA) has been used successfully for liver transplantation (LT) in recent years. However, there are few discourses in the literature which focus on the merits and weakness in perioperative management, biochemical changes, and postoperative recovery between TIVA and desflurane anesthesia (DES).

METHODS

We retrospectively compared the circumstances of liver transplantation recipients who had the surgery carried out under propofol-based TIVA or DES in the period from September 2007 to August 2010. Preoperative characteristics, date of intraoperative management, hemodynamic profiles, concentration of anesthetics, biochemical changes, and circumstances of postoperative recovery were retrieved from the hospital database for analysis.

RESULTS

We included 111 patients who received the surgery under either TIVA (n = 66) or DES (n = 45). Patient demographics, baseline laboratory data, operation time, and fluid management did not differ between the two groups. In comparison with the DES group, fewer patients had to be administered norepinephrine (21.2% vs. 42.2%; p = 0.020) in the TIVA group; moreover, the total dosage of norepinephrine was lower (0.003 ± 0.005 mg vs. 0.006 ± 0.008 mg; p = 0.012) in the TIVA group during liver reperfusion phase. Blood lactate level was higher in the DES group than in the TIVA group after the anhepatic phase. TIVA patients woke up faster than those in the DES group (54.0 ± 33.4 minutes vs. 95.0 ± 78.3 minutes; p = 0.034).

CONCLUSION

Our results suggest that propofol-based TIVA may provide better hemodynamics and microcirculation during the anhepatic phase in liver transplantation.

Total intravenous anaesthesia with high-dose remifentanil does not aggravate postoperative nausea and vomiting and pain, compared with low-dose remifentanil: a double-blind and randomized trial

The study was designed to investigate postoperative nausea and vomiting (PONV) in low- and high-dose remifentanil regimens for total intravenous anaesthesia (TIVA) in adult female patients with American Society of Anaesthesiologists physical status classification I undergoing local breast excision. Propofol and remifentanil 5 ng · mL(-1) (L group) or 10 ng · mL(-1) (H group) were administered for anaesthesia induction and maintenance. Propofol was titrated within range of 0.1 μg · mL(-1) to maintain bispectral index (BIS) values between 40 and 60. Haemodynamic parameters during the intra- and postoperative periods and 24 h postoperative visual analogue scale (VAS) and PONV were evaluated. Each group with 63 patients was analyzed. The H group showed higher use of remifentanil and lower use of propofol, with similar recovery time. Mean systemic arterial blood pressure (MBP), heart rate, and BIS did not differ significantly before and after endotracheal intubation in the H group. However, significant increases in MBP and BIS were apparent in the L group. Postoperative VAS, PONV incidence and scale, and Rhodes index did not differ significantly between the two groups. In conclusion, TIVA with high-dose remifentanil did not aggravate PONV with similar postoperative pain, compared with low-dose remifentanil. Furthermore, high-dose remifentanil showed more haemodynamic stability after endotracheal intubation. This trial is registered with KCT0000185.

Intubating conditions and side effects of propofol, remifentanil and sevoflurane compared with propofol, remifentanil and rocuronium: a randomised, prospective, clinical trial

BACKGROUND

Tracheal intubation without muscle relaxants is usually performed with remifentanil and propofol or sevoflurane. Remifentanil 1.0 to 4.0 μg·kg(-1) and propofol 2.0-3.0 mg·kg(-1) or sevoflurane up to 8.0 Vol% provide acceptable, i.e. excellent or good intubating conditions. We hypothesized that sevoflurane 1.0 MAC would provide acceptable intubating conditions when combined with propofol and remifentanil.

METHODS

Eighty-three patients to be intubated were randomised to two groups. The SEVO group received propofol 1.5 mg kg(-1), remifentanil 0.30 μg kg min(-1) and sevoflurane 1.0 MAC; the MR group received the same doses of propofol and remifentanil plus rocuronium 0.45 mg kg(-1). We evaluated intubation and extubation conditions, mean arterial pressure (MAP), heart rate (HR) and bispectral index (BIS). The vocal cords were examined for injury by videolaryngoscopy before and 24 hours after surgery.

RESULTS

ACCEPTABLE INTUBATING CONDITIONS WERE SEEN MORE FREQUENTLY WITH ROCURONIUM THAN WITH SEVOFLURANE: 97% versus 82%; p = 0.03; the subscore for vocal cords was comparable: 100% versus 98%. MAP before intubation decreased significantly compared with the MAP at baseline to the same extent in both groups; ephedrine IV was given in 15 (SEVO) versus 16 (MR) patients; p = 0.93. BIS at tracheal intubation was 27 (13-65) in the SEVO group, 29 (14-62) in the MR group; p = 0.07. Vocal cord injuries (oedema, haematoma) were similar: 4 patients in each group.

CONCLUSIONS

Overall intubating conditions were better when rocuronium was used; the subscore for vocal cords was comparable. The incidence of side effects was the same in the two groups.

TRIAL REGISTRATION

ClinicalTrials.Gov: NCT 01591031.

Considerations for the use of short-acting opioids in general anesthesia

Anesthesiologists play a critical role in facilitating a positive perioperative experience and early recovery for patients. Depending on the kind of procedure or surgery, a wide variety of agents and techniques are currently available to anesthesiologists to administer safe and efficacious anesthesia. Notably, the fast-track or ambulatory surgery environment requires the use of agents that enable rapid induction, maintenance, and emergence combined with minimal adverse effects. Short-acting opioids demonstrate a safe and rapid onset/offset of effect; that short effect is both predictable and precise. It also ensures easier titration and reduced or rapidly reversed side effects. Due to their distinct pharmacokinetic and pharmacodynamic properties, and, in one case, rapid extra-hepatic clearance of remifentanil, these agents have several applications in general anesthesia.

Propofol EC50 for inducing loss of consciousness is lower in the luteal phase of the menstrual cycle

BACKGROUND

Varying levels of female sex hormones during the menstrual cycle were found to influence the central nervous system. The goal of the present study was to investigate whether the median (50%) effective effect-concentration (EC50) of propofol inducing loss of consciousness (LOC) varies between the luteal and the follicular phases of the menstrual cycle.

METHODS

Twenty-two patients (follicular phase) and 20 patients (luteal phase) undergoing gynaecological procedures under general anaesthesia were enrolled on the study. Anaesthesia was conducted with a target-controlled infusion (TCI) of propofol. The initial target effect-site propofol concentration (Ceprop) was 3.5 µg ml(-1) and was adjusted stepwise by 0.5 µg ml(-1) at 4 min intervals by an up-down sequential method to reach LOC. Anaesthesia was maintained with a propofol TCI guided by the bispectral index. The correlation between female sex hormones and predicted Ceprop at the time of LOC was analysed and emergence time from anaesthesia was recorded.

RESULTS

Propofol EC50 to induce LOC was higher in patients in the follicular phase than those in the luteal phase (4.17 vs 3.58 µg ml(-1), P<0.05). Progesterone correlated significantly with Ceprop at LOC. Emergence time was also longer in the follicular group than in the luteal group (6.5 vs 5.0 min, P<0.05).

CONCLUSIONS

During general anaesthesia, patients in the luteal phase of the menstrual cycle had a lower propofol EC50 for LOC and a shorter emergence time compared with those in the follicular phase. Differences in progesterone levels between menstrual phases may contribute to these anaesthetic effects. Registry number of clinical trial ChiCTR-RCH-12002755.

The effect of general anaesthesia on gastric myoelectric activity in experimental pigs

Background

Surface electrogastrography (EGG) is a non-invasive method for clinical assessment of gastric myoelectrical activity. Different forms of general anaesthesia might have various effects on porcine EGG. The aim of this study was to evaluate the impact of different anaesthetic agents on EGG in experimental pigs.

Methods

Four 15-minute EGG intervals were recorded and analysed. A baseline EGG recording was started 20 minutes after intramuscular injection of ketamine and azaperone (periods A and B). Four different regimens of general anaesthesia followed immediately after the baseline EGG (5 pigs in each experimental group): thiopental, isoflurane, nitrous oxide and isoflurane plus nitrous oxide. EGG recordings followed for the next 30 minutes under general anaesthesia (periods C and D). The dominant frequencies of slow waves were compared between the baseline intervals A and B and periods C and D under general anaesthesia.

Results

The mean dominant frequency was within the normal range (2.3 – 3.5 cycles per minute) in all animals in all regimens. Thiopental general anaesthesia did not influence any change of the dominant frequency of slow waves. Nitrous oxide general anaesthesia increased the dominant frequency of slow waves in a statistically significant manner (baseline: 2.93 ± 0.53 and 3.01 ± 0.53; under general anaesthesia: 3.25 ± 0.34 and 3.29 ± 0.38 cycles per minute; p < 0.001, p = 0.003, p < 0.001, p < 0.001). Nitrous oxide together with isoflurane induced a statistically significant decrease of dominant frequency in the last 15-minute interval (2.66 ± 0.55 cycles per minute) compared to the baseline recording (2.81 ± 0.49; p = 0.030).

Conclusions

All changes of porcine gastric myoelectric activity assessed by the dominant frequency of slow waves during EGG remained within the normal range although some of them achieved statistical significance. Thus all tested agents used for general anaesthesia can be recommended in preclinical studies with porcine models focused on gastric myoelectric activity without any risk of compromising the results. Thiopental seems to be the most suitable as it did not cause any changes at all.

Usefulness of Intravenous Anesthesia Using a Target-controlled Infusion System with Local Anesthesia in Submuscular Breast Augmentation Surgery

Background

Patients have anxiety and fear of complications due to general anesthesia. Through new instruments and local anesthetic drugs, a variety of anesthetic methods have been introduced. These methods keep hospital costs down and save time for patients. In particular, the target-controlled infusion (TCI) system maintains a relatively accurate level of plasma concentration, so the depth of anesthesia can be adjusted more easily. We conducted this study to examine whether intravenous anesthesia using the TCI system with propofol and remifentanil would be an effective method of anesthesia in breast augmentation.

Methods

This study recruited 100 patients who underwent breast augmentation surgery from February to August 2011. Intravenous anesthesia was performed with 10 mg/mL propofol and 50 µg/mL remifentanil simultaneously administered using two separate modules of a continuous computer-assisted TCI system. The average target concentration was set at 2 µg/mL and 2 ng/mL for propofol and remifentanil, respectively, and titrated against clinical effect and vital signs. Oxygen saturation, electrocardiography, and respiratory status were continuously measured during surgery. Blood pressure was measured at 5-minute intervals. Information collected includes total duration of surgery, dose of drugs administered during surgery, memory about surgery, and side effects.

Results

Intraoperatively, there was transient hypotension in two cases and hypoxia in three cases. However, there were no serious complications due to anesthesia such as respiratory difficulty, deep vein thrombosis, or malignant hypertension, for which an endotracheal intubation or reversal agent would have been needed. All the patients were discharged on the day of surgery and able to ambulate normally.

Conclusions

Our results indicate that anesthetic methods, where the TCI of propofol and remifentanil is used, might replace general anesthesia with endotracheal intubation in breast augmentation surgery.

Intermittent manually controlled versus continuous infusion of propofol for deep sedation during interventional endoscopy: a prospective randomized trial

INTRODUCTION

Beside the traditional, intermittent bolus application of propofol, continuous propofol infusion via infusion pump is an alternative procedure for deep sedation during long-lasting interventional endoscopy. However, up to now, there are no randomized comparisons for gastrointestinal endoscopy.

METHODS

One hundred patients (ERCP: n = 60, EUS: n = 40) were randomly assigned to receive intermittent bolus application ("bolus group") or continuous infusion ("perfusor group") of propofol sedation after induction with 3 mg midazolam for deep sedation. Patients in the bolus group received an initial propofol dose according to body weight (bw <70 kg: 40 mg; bw ≥ 70 kg 60 mg). In the perfusor group, bw-adapted, continuous propofol infusion (6 mg/kg) via the Injectomat 2000 MC (Fresenius-Kabi) was administered after an initial bolus of 1 mg/kg. Vital signs, dose of propofol, patient cooperation (VAS 1-10), sedation depth, and the recovery time as well as the quality of recovery were evaluated.

RESULTS

Total propofol dose in the bolus group 305 ± 155 mg (100-570 mg) and in the perfusor group 343 ± 123 mg (126-590 mg, p = 0.5) were comparable. Oxygen saturation below 90% was seen in four patients of each group, with no need for assisted ventilation. Arterial blood pressure <90 mmHg was documented in two patients in the bolus group and seven patients in the perfusor group (p = 0.16). Patients' cooperation was rated as good in both groups (bolus group, 9.1 ± 0.9; perfusor group, 8.9 ± 1; p = 0.17). Recovery time was significantly shorter in the bolus group compared with the perfusor group (19 ± 5 versus 23 ± 6 min, p < 0.001) whereas the quality of recovery was nearly identical in both groups.

CONCLUSION

Both sedation regimens allow nearly identical good controllability of propofol sedation. However, recovery time was significantly slower and hypotension was tended to occur more often in the perfusor group.

Midazolam is associated with delay in recovery and agitation after ambulatory general anesthesia for dental treatment in patients with disabilities: a retrospective cohort study

PURPOSE

Some patients with intellectual disabilities (IDs) who undergo total intravenous anesthesia (TIVA) have complications associated with the anesthesia such as prolonged recovery. The purposes of this study were to estimate the frequency of TIVA complications among patients with IDs and to identify factors associated with TIVA complications.

MATERIALS AND METHODS

This study was designed as a retrospective cohort study. Study samples were selected from the clinical records of patients with IDs who underwent ambulatory general anesthesia in a special dental clinic at the Okayama University Hospital, Okayama, Japan. Predictor variables were patient background, anesthesia-related variables, and dental treatment. Outcome variables were delayed recovery and the complication of agitation. Factors affecting delayed recovery and complications were examined with multivariable analysis.

RESULTS

We enrolled 106 cases (81 male and 25 female patients) in this study. The mean age was 23.9 years. Serious complications were not observed in any cases. The amount of intravenous midazolam was an independent determinant of delayed recovery. Oral midazolam contributed to delayed recovery, although it is very useful for induction in patients with a high level of fear. Oral midazolam and a younger age were independent predictors of agitation.

CONCLUSIONS

Intravenous midazolam may not have an advantage in ambulatory general anesthesia. Oral midazolam contributes to delayed recovery and is an independent predictor of agitation.

[Future-oriented design of ambulatory surgery. Organizational aspects and medical options]

Ambulatory surgery continues to grow and is slowly becoming routine in the majority of cases. Although the development of ambulatory surgery in Germany appears to be somewhat delayed, this is actually a chance to learn from worldwide experiences and avoid the mistakes others made earlier. This article investigates current trends and developments in day case surgery and discusses the extended role and influence of the anesthetist in the perioperative setting.

Recovery of psychomotor function after total intravenous anesthesia with remifentanil-propofol or fentanyl-propofol

PURPOSE

Total intravenous anesthesia (TIVA) with propofol combined with remifentanil or fentanyl has commonly been used to achieve general anesthesia. The purpose of this study was to examine recovery of psychomotor function, by use of the Trieger dot test, after TIVA with remifentanil-propofol or with fentanyl-propofol.

METHODS

Forty patients were randomly divided into two groups of 20, to receive TIVA with either remifentanil-propofol (group R) or fentanyl-propofol (group F). Anesthesia was induced by intravenous injection of propofol. In group R, remifentanil at 0.3 μg/kg/min was infused continuously during surgery. In group F, 3 μg/kg fentanyl was injected as an initial dose and 1 μg/kg fentanyl was administered intravenously every 30 min during surgery. Psychomotor function, as measured by the Trieger dot test, was evaluated before anesthesia and 30, 60, 90, 120, and 150 min after the end of TIVA.

RESULTS

From assessment of the Trieger dot test, the number of dots missed in group R from 30 to 120 min after the end of TIVA was significantly lower than in group F. The maximum distance of dots missed in group R from 30 to 120 min after the end of TIVA was significantly shorter than in group F. The average distance of dots missed in group R from 30 to 120 min after the end of TIVA was significantly shorter than in group F.

CONCLUSION

Recovery of psychomotor function in TIVA with remifentanil-propofol is faster than that in TIVA with fentanyl-propofol.