The effect of anesthetic technique on early postoperative gastric emptying: comparison of propofol-remifentanil and opioid-free sevoflurane anesthesia

Opioid-free general anesthesia: considerations, techniques, and limitations

PURPOSE OF REVIEW

To discuss the role of opioids during general anesthesia and examine their advantages and risks in the context of clinical practice. We define opioid-free anesthesia (OFA) as the absolute avoidance of intraoperative opioids.

RECENT FINDINGS

In most minimally invasive and short-duration procedures, nonopioid analgesics, analgesic adjuvants, and local/regional analgesia can significantly spare the amount of intraoperative opioid needed. OFA should be considered in the context of tailoring to a specific patient and procedure, not as a universal approach. Strategies considered for OFA involve several adjuncts with low therapeutic range, requiring continuous infusions and resources, with potential for delayed recovery or other side effects, including increased short-term and long-term pain. No evidence indicates that OFA leads to decreased long-term opioid-related harms.

SUMMARY

Complete avoidance of intraoperative opioids remains questionable, as it does not necessarily ensure avoidance of postoperative opioids. Multimodal analgesia including local/regional anesthesia may allow OFA for selected, minimally invasive surgeries, but further research is necessary in surgeries with high postoperative opioid requirements. Until there is definitive evidence regarding procedure and patient-specific combinations as well as the dose and duration of administration of adjunct agents, it is imperative to practice opioid-sparing approach in the intraoperative period.

Impact of anesthetics on pyloric characteristics measured using the EndoFLIP® system in patients with gastroparesis

BACKGROUND

Pyloric distensibility has been reported as a predictive measure in gastroparesis. Measures can be obtained either during endoscopy under anesthesia or in unsedated patients. However, the impact of anesthetic drugs on the results of pyloric characteristics remains unknown. The objective of the present study was to determine the impact of anesthetics on pyloric characteristics measured using EndoFLIP® in patients with gastroparesis.

METHODS

Consecutive patients with gastroparesis from three French tertiary centers were retrospectively analyzed. Patients with a previous history of pyloric intervention were not considered for analysis. Medical records were reviewed for the potential use of anesthetic drugs during EndoFLIP® measurement.

KEY RESULTS

One hundred twenty-five patients were included in the present study [median age: 55.0 years (43.0-66.0)]. Thirty-four patients (27.2%) had pyloric assessment without general anesthesia and 91 patients (72.8%) with general anesthesia. Pyloric pressure at 40 mL of distension was higher in patients with general anesthesia in comparison with patients without general anesthesia [18.7 (13.0-25.6) mmHg vs. 15.4 (11.9-20.7) mmHg; p = 0.044)]. In multivariate analysis, suxamethonium chloride administration was associated with decreased pyloric distensibility (OR: 3.9; 95% CI: 1.3-11.4; p = 0.013) while ephedrine was rather associated with increased pyloric distensibility (OR: 0.3; 95% CI: 0.1-0.9; p = 0.036).

CONCLUSIONS AND INFERENCES

This study is the first to have found an impact of general anesthesia on pyloric measurement using the EndoFLIP®. Therefore, further studies are needed to confirm these findings, if possible, prospective studies.

A randomized controlled trial of the effect of ramosetron on postoperative restoration of bowel motility after gynecologic laparoscopic surgery

OBJECTIVE

To investigate the effect of ramosetron after gynecological laparoscopic surgery on the recovery of bowel function.

METHODS

A prospective randomized controlled trial conducted at Kyung Hee University hospital, South Korea, from August 2016 to September 2017. Patients were randomized to receive either 10 mg dexamethasone before induction of anesthesia (control group C), followed by intravenous administration of patient-controlled analgesia (IV-PCA) or 2 ml normal saline before induction of anesthesia and 0.6 mg ramosetron (study group R) administered with IV-PCA.

RESULTS

A total of 88 patients were enrolled. Times to first flatus (group C 23.98 ± 6.31 vs. group R 27.14 ± 9.56 h; P = 0.148) and first defecation (group C 36.16 ± 16.04 vs. group R 43.41 ± 20.01 h; P = 0.138) showed no statistically significant differences. No significant differences were observed in the frequency of postoperative nausea and vomiting (PONV) and demand for additional analgesics. Multiple linear regression for analysis of factors affecting time to first flatus revealed no significant results.

CONCLUSION

Ramosetron did not delay bowel movement recovery after gynecologic laparoscopic surgery and was as effective as dexamethasone in regulating PONV. Ramosetron can be used with IV-PCA without concerns about delay in recovery of bowel function. ClinicalTrials.gov registration number: NCT02849483.

[Comparison of post-operative nausea and vomiting with intravenous versus inhalational anesthesia in laparotomic abdominal surgery: a randomized clinical trial]

BACKGROUND

Postoperative Nausea and Vomiting (PONV) is a multifactorial surgical complication with an unclear underlying cause. Anesthetic methods, patients' characteristics and the type of surgery are considered as factors affecting PONV. This study was designed to compare the effect of inhalational and intravenous anesthesia in abdominal surgery on the incidence and severity of PONV.

METHODS

A single-blinded prospective randomized clinical trial on 105 patients aged 18-65 years was carried out. Patients were divided in two groups of Total Intravenous Anesthesia (TIVA) and Inhalational anesthesia. The incidence and severity of PONV were examined at 0, 2, 6, 12, and 24hours after the surgery. The use of a rescue antiemetic was also evaluated.

RESULTS

Fifty point nine percent of the patients in the inhalation group and 17.3% of the patients in the intravenous group developed PONV (p <0.001). The incidence of vomiting was reported in 11.3% of the Inhalational group and 3.8% of the TIVA group (p=0.15), and 24.5% of patients in the Inhalation group and 9.6% of patients in the intravenous group needed an antiemetic medication (p=0.043).

CONCLUSION

The incidence of postoperative nausea and vomiting and the need for administration of an antiemetic rescue drug, and the severity of nausea in patients were significantly lower in the TIVA group.

Comparison of post-operative nausea and vomiting with intravenous versus inhalational anesthesia in laparotomic abdominal surgery: a randomized clinical trial

Background

Postoperative Nausea and Vomiting (PONV) is a multifactorial surgical complication with an unclear underlying cause. Anesthetic methods, patients' characteristics and the type of surgery are considered as factors affecting PONV. This study was designed to compare the effect of inhalational and intravenous anesthesia in abdominal surgery on the incidence and severity of PONV.

Methods

A single-blinded prospective randomized clinical trial on 105 patients aged 18 − 65 years was carried out. Patients were divided into two groups of Total Intravenous Anesthesia (TIVA) and inhalational anesthesia. The incidence and the severity of PONV were examined at 0, 2, 6, 12 and 24 hours after the surgery. The use of a rescue antiemetic was also evaluated.

Results

50.9% of the patients in the inhalation group and 17.3% of the patients in the intravenous group developed PONV (p <  0.001). The incidence of vomiting was reported in 11.3% of the inhalational group and 3.8% of the TIVA group (p =  0.15). 24.5% of patients in the inhalation group and 9.6% of patients in the intravenous group needed an antiemetic medication (p =  0.043).

Conclusion

The incidence of postoperative nausea and vomiting and the need for administration of an antiemetic rescue drug and the severity of nausea in patients were significantly lower in the TIVA group.

The effect of chlorzoxazone on acute pain after spine surgery. A randomized, blinded trial

BACKGROUND

Chlorzoxazone is a muscle relaxant administered for musculoskeletal pain, and as an analgesic adjunct for post-operative pain. Chlorzoxazone for low back pain is currently not advised due to the lack of placebo-controlled trials. We explored the effect of chlorzoxazone on acute pain after spine surgery.

METHODS

One hundred and ten patients were randomly assigned to 500 mg oral chlorzoxazone or placebo in this blinded study of patients having spine surgery under general anaesthesia. In the 4 h trial period analgesia consisted of IV patient-controlled analgesia (morphine bolus 2.5 mg). Primary outcome was pain during mobilization (visual analogue scale) 2 h after the intervention. Secondary outcomes were pain at rest, opioid consumption, nausea, vomiting, sedation and dizziness.

RESULTS

For pain during mobilization 2 h after intervention, there was no significant difference between groups: 51 (21) vs. 54 (25) mm in the chlorzoxazone and placebo groups, respectively, mean difference 3 mm (95% CI -8 to 10), P = 0.59. For pain during mobilization and at rest (wAUC 1-4 h), there were no significant differences between groups. There was no significant difference in total IV morphine use 0-4 h: median 10 (7-21) vs. 13 (5-19) mg in the chlorzoxazone and placebo groups, respectively, P = 0.82. We found no significant difference in adverse effects.

CONCLUSION

No analgesic effect of single-dose chlorzoxazone was demonstrated in patients with acute pain after spine surgery. Based on these findings, chlorzoxazone cannot be recommended for immediate treatment of acute pain after such procedures.

Effects of Anesthesia on Pediatric pH Impedance

OBJECTIVES

Anesthesia can alter gastric and small intestinal motility, but its effect on gastroesophageal reflux (GER) is unclear. We set out to evaluate the effect of anesthesia on pH-multichannel intraluminal impedance (pH impedance) evaluation of GER.

METHODS

Retrospective single-center analysis of 95 pH impedance probe studies performed in patients both with anesthesia exposure and esophagogastroduodenoscopy (n = 50) and without (n = 45).

RESULTS

Increased acid reflux per hour, nonacid reflux per hour, and total reflux per hour were observed in the first 4 hours, both overall and in children 1 year or older and in both sedation groups. This difference remained for the older children without sedation by multiple regression analysis for nonacid reflux per hour and total reflux per hour. Patients using proton pump inhibitors had more nonacid reflux events per hour and total reflux events per hour regardless of sedation.

CONCLUSIONS

Based on the results of the present study, there is no need to eliminate the data collected immediately after placement of the probe in children younger than 1 year of age, but in those who are 1 year or older without sedation, there may be a greater number of reflux events in the first 4 hours. The first 4 hours, therefore, should be carefully evaluated in patients older than 1 year of age. Further study is needed to provide normative data for the first 4 hours versus the later time period, both for those undergoing sedation and for unsedated patients, to validate the findings from the present study and to better understand the mechanism of GER.

Acetaminophen absorption kinetics in altered gastric emptying: establishing a relevant pharmacokinetic surrogate using published data

Acetaminophen has been used as a tool for clinical and nonclinical experimental designs that evaluate gastric emptying because acetaminophen is not absorbed in stomach but efficiently absorbed from the small intestine. Published pharmacokinetic data of acetaminophen in subjects with normal gastric emptying vs. impaired gastric emptying (i.e., morphine treatment) were evaluated to select a key surrogate. Using Caverage (average concentration), computed from the exposure within the first hour, individual rank distribution was plotted across different studies. Caverage was highly correlated with Cmax (maximum concentration) in subjects with normal gastric emptying (R(2) = .7532) but not in those where gastric emptying was impaired (R(2) = .0213). The 50th percentile value of the distribution pattern of 1/Caverage in acetaminophen+morphine-treated group (coincided with the first shift in the slope) was considered as the cutoff point to figure out the impaired gastric emptying. The individual rank distribution plots for 1/Caverage across different studies supported similar trends in subjects with normal gastric emptying but showed a distinct distribution pattern in the cohort of impaired gastric emptying. Caverage, calculated within the first hour of dosing of acetaminophen (average concentration at 0-1 hour, C0-1havg), can be used as a key surrogate to distinguish the effects of gastric emptying on the absorption of acetaminophen. A 4 μg/mL C0-1havg of acetaminophen (dose: 1.5 g) may be used as cutoff point in future clinical investigations of acetaminophen to clarify the role of gastric emptying.

Tacrolimus exposure and mycophenolate pharmacokinetics and pharmacodynamics early after liver transplantation

BACKGROUND

Mycophenolic acid (MPA) and tacrolimus play important roles in immunosuppressive therapy after solid organ transplantation (Tx) and show large intra- and interindividual pharmacokinetic (PK) variabilities. The purpose of this study was to describe the intra- and interindividual variabilities of MPA and tacrolimus PKs during the first 3 weeks after adult liver transplantation. Furthermore, inosine monophosphate dehydrogenase activity was investigated.

MATERIALS

This study describes PK and pharmacodynamic parameters of MPA and the PKs of tacrolimus in 16 liver transplant recipients, in 4 follow-up periods (I-IV).

RESULTS

The area under the concentration-time curve (AUC(0-12 hours)) for tacrolimus was low early after Tx (eg, median 78.6 around day 4) and variable in all 4 periods ranging from 3.8 to 267 μg h/L, whereas the predose concentrations (C₀) were 0.0-17.9 μg/L. From periods I to IV, the tacrolimus dose was doubled and the median dose per body weight-adjusted AUC(0-12 hours) increased by 123% (P = 0.017). The AUC(0-12 hours) of MPA was in the range 8.6-57.4 mg h/L, with median values from 21.9 to 27.8 mg h/L, whereas C₀ was between 0.0 and 7.3 mg/L in the 4 periods (medians from 1.2 to 1.6 mg/L). The maximum inhibition of inosine monophosphate dehydrogenase within a dose interval ranged from 9.5% to 100%.

CONCLUSIONS

This study confirmed the large variability in the PKs of tacrolimus and MPA in liver transplant recipients. In particular, the MPA AUC(0-12 hours) was consistently low in all 4 periods. We also observed a low tacrolimus exposure during the first days after transplant compared with the following weeks.

Anaesthetic regimens for day-procedure laparoscopic cholecystectomy

BACKGROUND

Day surgery involves admission of selected patients to hospital for a planned surgical procedure with the patients returning home on the same day. An anaesthetic regimen usually involves a combination of an anxiolytic, an induction agent, a maintenance agent, a method of maintaining the airway (laryngeal mask versus endotracheal intubation), and a muscle relaxant. The effect of anaesthesia may continue after the completion of surgery and can delay discharge. Various regimens of anaesthesia have been suggested for day-procedure laparoscopic cholecystectomy.

OBJECTIVES

To compare the benefits and harms of different anaesthetic regimens (risks of mortality and morbidity, measures of recovery after surgery) in patients undergoing day-procedure laparoscopic cholecystectomy.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (Issue 10, 2013), MEDLINE (PubMed) (1987 to November 2013), EMBASE (OvidSP) (1987 to November 2013), Science Citation Index Expanded (ISI Web of Knowledge) (1987 to November 2013), LILACS (Virtual Health Library) (1987 to November 2013), metaRegister of Controlled Trials (http://www.controlled-trials.com/mrct/) (November 2013), World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) portal (November 2013), and ClinicalTrials.gov (November 2013).

SELECTION CRITERIA

We included randomized clinical trials comparing different anaesthetic regimens during elective day-procedure laparoscopic cholecystectomy (irrespective of language or publication status).

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trials for inclusion and independently extracted the data. We calculated the risk ratio, rate ratio or mean difference with 95% confidence intervals based on intention-to-treat or available data analysis.

MAIN RESULTS

We included 11 trials involving 1069 participants at low anaesthetic risk. The sample size varied from 40 to 300 participants. We included 23 comparisons. All trials were at a high risk of bias. We were unable to perform a meta-analysis because there were no two trials involving the same comparison. Primary outcomes included perioperative mortality, serious morbidity and proportion of patients who were discharged on the same day. There were no perioperative deaths or serious adverse events in either group in the only trial that reported this information (0/60). There was no clear evidence of a difference in the proportion of patients who were discharged on the same day between any of the comparisons. Overall, 472/554 patients (85%) included in this review were discharged as day-procedure laparoscopic cholecystectomy patients. Secondary outcomes included hospital readmissions, health-related quality of life, pain, return to activity and return to work. There was no clear evidence of a difference in hospital readmissions within 30 days in the only comparison in which this outcome was reported. One readmission was reported in the 60 patients (2%) in whom this outcome was assessed. Quality of life was not reported in any of the trials. There was no clear evidence of a difference in the pain intensity, measured by a visual analogue scale, between comparators in the only trial which reported the pain intensity at between four and eight hours after surgery. Times to return to activity and return to work were not reported in any of the trials.

AUTHORS' CONCLUSIONS

There is currently insufficient evidence to conclude that one anaesthetic regimen for day-procedure laparoscopic cholecystectomy is to be preferred over another. However, the data are sparse (that is, there were few trials under each comparison and the trials had few participants) and further well designed randomized trials at low risk of bias and which are powered to measure differences in clinically important outcomes are necessary to determine the optimal anaesthetic regimen for day-procedure laparoscopic cholecystectomy, one of the commonest procedures performed in the western world.

The pharmacokinetics of prednisolone and prednisone in adult liver transplant recipients early after transplantation

BACKGROUND

Glucocorticoids represent a cornerstone in the immunosuppressive therapy after solid organ transplantation. Interconversion between active and inactive states of glucocorticoids (ie, prednisolone and prednisone) is catalyzed by the enzymes 11β-hydroxysteroid dehydrogenases 1 and 2.

MATERIALS

This study investigated the pharmacokinetics of prednisolone and prednisone in 16 liver transplant recipients. Blood samples were collected in four 12-hour dosing intervals during the first 3 weeks posttransplant, including samples drawn at 13 time points.

RESULTS

Area under the time-concentration curve of prednisolone was 3-13 μg·h·mL·mg·kg with maximum concentrations (Cmax) between 0.37 and 2.5 μg·mL·mg·kg and trough concentrations (C0) between 0.13 and 1.1 μg·mL·mg·kg. The elimination half-lives were 1.9-10.3 hours. Apparent volume of distribution (VD/F) and apparent clearance (Cl/F) were 23-159 L and 4.7-28.7 L/h, respectively.

CONCLUSIONS

This study demonstrated large intraindividual and interindividual variabilities in glucocorticoid pharmacokinetics. The results suggest that current prednisolone dosing early after liver transplantation might be too high, in particular when coadministered with methylprednisolone. These findings indicate a potential for improvement by personalized dosing of glucocorticoids in organ transplantation.

Intra-operative change of gastric pH during laparotomic cholecystectomy under general anaesthesia: A prospective case-control study

Background:

Gastric decompression by suctioning often shows greenish/greenish-yellow-coloured gastric aspirates following cholecystectomy under general anaesthesia (GA). Possible intraoperative regurgitation of duodenal contents into stomach because of surgical manipulation may be the reason for such alteration in colour of the gastric secretions.

Aim:

We conducted this study to determine whether there were any pH changes of gastric secretions during laparotomic cholecystectomy operation to confirm our hypothesis of regurgitation of duodenal contents into the stomach.

Settings and Designs:

Prospective observational controlled study in the Department of Anaesthesiology and Critical Care in a tertiary care university teaching hospital.

Methods:

Fifty adult ASA I and II patients scheduled for open cholecystectomy operation under GA were included in the study group and another 50 non-abdominal surgical patients without any gall bladder disease were taken as controls. Three to five milliliters of gastric secretions were aspirated just after intubation and also before reversal of residual neuromuscular blockade for analysis of pH.

Statistical Analysis:

Analysis of variance test and Chi-square test with Fisher's exact correction were used for statistical analysis. Differences were significant when the P value was <0.05.

Results:

Post-operative values of pH in the study group were significantly higher than their pre-operative values (2.40±1.10 vs. 4.04±1.6, P≤0.001). Forty-nine patients (98%) in the study group had altered coloured post-operative gastric aspirations, while no patient in the control group had such changes (P<0.001).

Conclusions:

A significant change in gastric pH takes place during laparotomic cholecystectomy due to reflux of duodenal content into the stomach.

Remifentanil, a different opioid: potential clinical applications and safety aspects

IMPORTANCE OF THE FIELD

Opioids play an important role in every aspect of modern anesthetic practice. Remifentanil is an ultra-short-acting opioid featuring a unique pharmacokinetic profile allowing clinical versatility and improved control of its action. In this review, we assess the pharmacology of remifentanil, its clinical uses as well as safety issues on its action on the major organ systems and in particular clinical settings.

AREAS COVERED IN THIS REVIEW

A synthesis of evidence from a MEDLINE search for articles from 1993 to 2009 for available up-to-date information on remifentanil and its current applications and safety profile.

WHAT THE READER WILL GAIN

A synopsis of the unique pharmacokinetic properties of remifentanil and its action on major organ systems will provide insight on the safe and effective use of the drug in a variety of clinical settings.

TAKE HOME MESSAGE

Remifentanil is a valuable opioid in the armamentarium of the clinician, providing great clinical flexibility and safety but vigilance is required to avoid pitfalls.

Comparison of recovery characteristics, postoperative nausea and vomiting, and gastrointestinal motility with total intravenous anesthesia with propofol versus inhalation anesthesia with desflurane for laparoscopic cholecystectomy: A randomized controlled study

BACKGROUND

Clinical effects, recovery characteristics, and costs of total intravenous anesthesia with different inhalational anesthetics have been investigated and compared; however, there are no reported clinical studies focusing on the effects of anesthesia with propofol and desflurane in patients undergoing laparoscopic cholecystectomy.

OBJECTIVE

The aim of this study was to determine the effects of total intravenous anesthesia with propofol and alfentanil compared with those of desflurane and alfentanil on recovery characteristics, postoperative nausea and vomiting (PONV), duration of hospitalization, and gastrointestinal motility.

METHODS

Patients classified as American Society of Anesthesiologists physical status I or II undergoing elective laparoscopic cholecystectomy due to benign gallbladder disease were enrolled in the study. Patients were randomly assigned at a 1:1 ratio to receive total intravenous anesthesia with propofol (2-2.5 mg/kg) and alfentanil (20 μg/kg) or desflurane (4%-6%) and alfentanil (20 μg/kg). Perioperative management during premedication, intraoperative analgesia, relaxation, ventilation, and postoperative analgesia were carried out identically in the 2 groups. Extubation time, recovery time, PONV, postoperative antiemetic requirement, time to gastrointestinal motility and flatus, duration of hospitalization, and adverse effects were recorded. Postoperative pain was assessed using a visual analogue scale.

RESULTS

Sixty-eight patients were assessed for inclusion in the study; 5 were excluded because they chose open surgery and 3 did not complete the study because they left the hospital. Sixty patients (33 women, 27 men) completed the study. Recovery time was significantly shorter in the propofol group (n = 30) compared with the desflurane group (n = 30) (8.0 [0.77] vs 9.2 [0.66] min, respectively; P < 0.005). Fifteen patients (50.0%) in the propofol group and 20 patients (66.7%) in the desflurane group experienced nausea during the first 24 hours after surgery. The difference was not considered significant. In the propofol group, significantly fewer patients had vomiting episodes compared with those in the desflurane group (2 [6.7%] vs 16 [53.3%]; P < 0.005). Significantly fewer patients in the propofol group required analgesic medication in the first 24 hours after surgery compared with those in the desflurane group (10 [33.3%] vs 15 [50.0%]; P < 0.005). Patients in the propofol group experienced bowel movements in a significantly shorter period of time compared with patients in the desflurane group (8.30 [1.67] vs 9.76 [1.88] hours; P = 0.02). The mean time to flatus occurred significantly sooner after surgery in the propofol group than in the desflurane group (8.70 [1.79] vs 9.46 [2.09] hours; P = 0.01). The duration of hospitalization after surgery was significantly shorter in the propofol group than in the desflurane group (40.60 [3.49] vs 43.60 [3.56] hours; P = 0.03).

CONCLUSION

Total intravenous anesthesia with propofol and alfentanil was associated with a significantly reduced rate of PONV and analgesic consumption, shortened recovery time and duration of hospitalization, accelerated onset of bowel movements, and increased patient satisfaction compared with desflurane and alfentanil in these patients undergoing laparoscopic surgery who completed the study.

Effect of distal subtotal gastrectomy with preservation of the celiac branch of the vagus nerve to gastrointestinal function: an experimental study in conscious dogs

OBJECTIVE

To evaluate the effects of distal subtotal gastrectomy with preservation of the celiac branch of the vagus nerve on gastrointestinal function.

SUMMARY BACKGROUND DATA

The operative procedure of distal subtotal gastrectomy with preservation of the celiac branch of the vagus nerve is now in the spotlight in Japan with the goal of finding a function-preserving surgical technique. However, there has been no analysis of the effect of this type of surgery on gastrointestinal function. In this article, we describe the results of a fundamental experiment on distal subtotal gastrectomy with preservation of the celiac branch of the vagus nerve.

METHODS

Twenty conscious dogs were divided into 2 groups, each subdivided into 2 groups of 5: a normal intact dog group (NG) divided into 2 groups, with preservation (PNG) and resection (RNG; these dogs were truncally vagotomized including transaction of the celiac branch) of the celiac branch, and a gastrectomy dog group (GG) divided into 2 groups, with preservation (PGG) and resection (RGG) of the celiac branch. The motility of the dogs was recorded using strain gauge force transducers. The effects of the preservation of the celiac branch of the vagus nerve on gastrointestinal motility, gastric emptying, and pancreatic insulin release were evaluated.

RESULTS

The motility index of gastrointestinal motility with preservation of the celiac branch was higher than the motility index with resection of the celiac branch in fasted and fed of NG and GG. In gastric emptying, significant differences were found between the PNG and RNG but not between the PGG and RGG. In the fasted state for 80 minutes of the PNG and PGG, the serum insulin concentration reached a peak during the early phase III at 20 minutes in the gastric body and the antrum.

CONCLUSIONS

This study has shown that it is effective to preserve the celiac branch of the vagus nerve for gastroduodenal motility, gastric emptying, and pancreatic insulin release after a gastrectomy.

Perioperative fluctuations of lamotrigine serum levels in patients undergoing epilepsy surgery

Some patients undergoing epilepsy surgery suffer from early postoperative seizures which may have a negative impact on later outcome. Factors contributing to these seizures have not to date been examined systematically. We hypothesized that reduction of postoperative serum levels of antiepileptic drugs (AED) may be one risk factor for early postoperative seizures.

METHODS

We retrospectively reviewed medical records from 20 patients treated with lamotrigine (LTG) who underwent epilepsy surgery between January 1997 and February 2004. Demographic data, anaesthesiological and surgical procedures, co-medication, and pre- as well as one or more postoperative LTG serum levels were evaluated.

RESULTS

We found a significant decrease in LTG serum levels, amounting to more than 20% (mean 46%, range 21.9-69.1%), in 16 of 20 patients (80%). Six patients (30%) suffered from seizures in the first 2 weeks after surgery. In three patients, postoperative seizures occurred isochronically with the LTG serum level nadir. The magnitude of the reduction in serum levels was not influenced by age, sex, duration of the operation, the type of anaesthetic drugs or the postoperative co-medication.

DISCUSSION

Reductions in LTG serum levels are a relevant contributing factor for early postoperative seizures. Postoperative alteration of the gastrointestinal motility and transient time leading to delayed absorption and reduced bioavailability of AED may be a major risk factor. Therefore, close monitoring of postoperative LTG serum levels is necessary and should lead to a temporary dose augmentation and/or anticonvulsant co-medication with benzodiazepines in case of a pronounced reduction of serum levels.