Effects of intravenous lidocaine, dexmedetomidine, and their combination on IL-1, IL-6 and TNF-α in patients undergoing laparoscopic hysterectomy: a prospective, randomized controlled trial.

BACKGROUND: Surgical-related inflammatory responses have negative effects on postoperative recovery. Intravenous (IV) lidocaine and dexmedetomidine inhibits the inflammatory response. We investigated whether the co-administration of lidocaine and dexmedetomidine could further alleviate inflammatory responses compared with lidocaine or dexmedetomidine alone during laparoscopic hysterectomy. METHODS: A total of 160 patients were randomly allocated into four groups following laparoscopic hysterectomy: the control group (group C) received normal saline, the lidocaine group (group L) received lidocaine (bolus infusion of 1.5 mg/kg over 10 min, 1.5 mg/kg/h continuous infusion), the dexmedetomidine group (group D) received dexmedetomidine (bolus infusion of 0.5 µg/kg over 10 min, 0.4 µg/kg/h continuous infusion), and the lidocaine plus dexmedetomidine group (group LD) received a combination of lidocaine (bolus infusion of 1.5 mg/kg over 10 min, 1.5 mg/kg/h continuous infusion) and dexmedetomidine (bolus infusion of 0.5 µg/kg over 10 min, 0.4 µg/kg/h continuous infusion). The levels of plasma interleukin-1 (IL-1), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) at different time points were the primary outcomes. Secondary outcomes included hemodynamic variables, postoperative visual analogue scale (VAS) scores, time to first flatus, and incidence of nausea and vomiting after surgery. RESULTS: The levels of plasma IL-1, IL-6, and TNF-α were lower in groups D and LD than in group C and were lowest in group LD at the end of the procedure and 2 h after the operation (P < 0.05). The VAS scores were decreased in groups D and LD compared with group C (P < 0.05). The heart rate (HR) was decreased at the end of the procedure and 2 h after the operation in groups D and LD compared to groups C and L (P < 0.001). The mean blood pressure (MBP) was lower at 2 h after the operation in groups L, D, and LD than in group C (P < 0.001). There was a lower incidence of postoperative nausea and vomiting (PONV) in group LD than in group C (P < 0.05). CONCLUSIONS: The combination of lidocaine and dexmedetomidine significantly alleviated the inflammatory responses, decreased postoperative pain, and led to fewer PONV in patients undergoing laparoscopic hysterectomy. TRIAL REGISTRATION: ClinicalTrials.gov ( NCT03276533 ), registered on August 23, 2017.

Effects of hydromorphone and morphine intravenous analgesia on plasma motilin and postoperative nausea and vomiting in patients undergoing total hysterectomy.

OBJECTIVE: To observe the effects of hydromorphone and morphine intravenous analgesia on plasma motilin and postoperative nausea and vomiting in patients undergoing a total hysterectomy. PATIENTS AND METHODS: 80 patients who underwent hysterectomy from April 2015 to June 2016 were randomly divided into two groups, with 40 patients in each group. The two groups received an intravenous infusion of hydromorphone or morphine for analgesia. The VAS pain score and Ramsey sedation score were recorded 4, 8, 12, 24, and 48 hours after the first dose of analgesia. The scores of nausea and vomiting were recorded. The levels of motilin were determined by radioimmunoassay before anesthesia, after anesthesia, during hysterectomy and 1 day after the operation. The results showed that the analgesic effect of hydromorphone was more rapid than morphine. RESULTS: There were significant differences in VAS scores between the two groups at each time point (p<0.05), indicating that the analgesic effect of hydromorphone was better than morphine's one. The scores of Ramsay sedation were less than 6 points at each time point within 48 hours after the operation. The content of plasma motilin in the hydromorphone group was higher than that in the morphine group during the first day after anesthesia. There were 34 cases (85%) of mild nausea and vomiting within 24 hours after the operation in the hydromorphone group. In the morphine group, there were 16 cases (40%) of mild nausea and vomiting within 24 hours after the operation, 10 cases (25%) of severe nausea and vomiting. CONCLUSIONS: The occurrence of severe malignant vomiting after the use of morphine was more than that after the use of hydromorphone. Normal level and function of motilin is the basis of avoiding nausea and vomiting. Too fast or too slow gastrointestinal motility can induce postoperative nausea and vomiting.

Quick rehabilitation nursing improves the recovery of colon cancer patients after laparoscopy.

Colon cancer is a common malignant tumor with particularly high morbidity and mortality. The aim of this study was to compare the effect of quick rehabilitation nursing and routine nursing in postoperative recovery of patients with colon cancer after laparoscopic surgery. Two hundred forty patients with colon cancer were classified into four random groups (A, B, C and D, with 60 patients in each group). All patients underwent surgery to remove the colon tumor by laparoscopy under general anesthesia. Patients in groups A and B received quick rehabilitation nursing for post-surgery recovery. In group C patients, local anesthesia associated with quick rehabilitation nursing for post-surgery recovery was used. Group D was used as control group and the patients were treated based on routine nursing. Time to get out of bed, first bowel movement time and the average time of hospitalisation in group A was lower than group D (p less than 0.05), postoperative leukocyte level as well as the occurrence rate of nausea and vomiting, ankylenteron and pelvic adhesion was decreased in group A compared to group D (p less than 0.05), but the postoperative albumin and total protein level was higher than group D (p less than 0.05). The serum level of C-Reactive Protein (CRP) and interleukin 6 (IL-6) in group A was decreased compared to group D several days after surgery (p less than 0.05); group B had 4 cases of intestinal obstruction after surgery that could be cured through conservative treatment, while group D had 10 cases of intestinal obstruction, 8 of which could be cured through conservative treatment and two needed surgery (p less than 0.05); VAS for pain degree of group C in active state was clearly lower at 1h, 5h, 7h, 15h, 30h and 42h after surgery, and side effects of postoperative analgesia were clearly reduced. Time to get out of bed was obviously decreased, while there was no evident effect on postoperative dosage, chronic pain and complications. Adopting quick rehabilitation nursing can effectively reduce occurrence of complications and postoperative pain, speed up the recovery of gastrointestinal function, shorten the length of stay, and improve patients’ satisfaction.

[Effects of auricular point sticking on plasma motilin in patients after gynecological laparoscopic operation under general anesthesia].

OBJECTIVE: To observe the clinical efficacy of auricular point sticking on prevention and treatment of gastrointestinal complications after gynecological laparoscopic operation of general anesthesia, and to explore whether it is achieved by regulating the secretion of plasma motilin (MTL). METHODS: Sixty patients who received selective gynecological laparoscopy under general anesthesia were randomly assigned into an observation group and a control group, 30 patients in each one. The patients in the observation group were treated with auricular point sticking at each morning and night, 30 min before anesthesia, revival after surgery and 24 h after surgery. The adhesive fabric with vaccaria seeds was pressed at shenmen (TF4), wei (CO4), benmen (CO3), jiaogan (AH6a) and pizhixia (AT4) for 3 to 5 min until the sensation of sourness, distension and numb appeared. The treatment was given for one week. The patients in the control group were treated only with similar adhesive fabric at auricular points at identical time points; each auricular point was pressed for 3 to 5 min. The anus exhaust time, defecating time and borborygmus were recorded; the level of plasma MTL was tested 30 min before anesthesia, 24 h after o-peration and 48 h after operation; the occurrence of nausea and vomiting from the end of operation to the end of treatment were also recorded. RESULTS: Compared with the control group, the occurrence of nausea after operation was reduced in the observation group (P<0.05), and the anus exhaust time and defecating time were shortened (both P<0.05), and the recovery of borborygmus was improved (P<0.05). The levels of MTL 24 h and 48 h after surgery were higher than those before operation in the two groups (all P<0.05); The levels of MTL 24 h and 48 h after surgery in the observation group were significantly lower than those in the control group (both P<0.05). CONCLUSIONS: The assist of auricular point sticking could reduce the occurrence of nausea-vomiting and accelerate the recovery of gastrointestinal function in gynecological laparoscopic operation under general anesthesia, which is likely to be related with the inhibition on excess secretion of MTL.

Shortened preoperative fasting for prevention of complications associated with laparoscopic cholecystectomy: a meta-analysis.

Objective Routine fasting (12 h) is always applied before laparoscopic cholecystectomy, but prolonged preoperative fasting causes thirst, hunger, and irritability as well as dehydration, low blood glucose, insulin resistance and other adverse reactions. We assessed the safety and efficacy of a shortened preoperative fasting period in patients undergoing laparoscopic cholecystectomy. Methods We searched PubMed, Embase and Cochrane Central Register of Controlled Trials up to 20 November 2015 and selected controlled trials with a shortened fasting time before laparoscopic cholecystectomy. We assessed the results by performing a meta-analysis using a variety of outcome measures and investigated the heterogeneity by subgroup analysis. Results Eleven trials were included. Forest plots showed that a shortened fasting time reduced the operative risk and patient discomfort. A shortened fasting time also reduced postoperative nausea and vomiting as well as operative vomiting. With respect to glucose metabolism, a shortened fasting time significantly reduced abnormalities in the ratio of insulin sensitivity. The C-reactive protein concentration was also reduced by a shortened fasting time. Conclusions A shortened preoperative fasting time increases patients' postoperative comfort, improves insulin resistance, and reduces stress responses. This evidence supports the clinical application of a shortened fasting time before laparoscopic cholecystectomy.

Association of Postoperative Nausea and Vomiting Incidence With Neutrophil-Lymphocyte Ratio in Ambulatory Maxillofacial Surgery.

PURPOSE: Postoperative nausea and vomiting (PONV) constitutes an important factor in ambulatory surgery. The mechanisms of the antiemetic action of potent anti-inflammatory corticosteroids, which are used extensively for the treatment of PONV, as well as the association between PONV and inflammation, have not been investigated sufficiently. We aimed to establish the association between the neutrophil-lymphocyte ratio (NLR) and postoperative antiemetic administration, as well as to investigate whether the NLR would be a biomarker for PONV. MATERIALS AND METHODS: The anesthesia records of American Society of Anesthesiologists (ASA) physical status I or II patients who underwent ambulatory routine oral surgery under general anesthesia were evaluated after we obtained ethical approval from the faculty ethics committee. A 5-point scale was used to score PONV. Metoclopramide (Metpamid, Istanbul, Turkey) was used as the first choice in patients who had a PONV scale score of 1 or higher. Data regarding metoclopramide administration during extubation and discharge periods were analyzed. Sixty-four patients were randomized and enrolled in the study with an NLR less than 2 (group I, n = 37) or an NLR greater than 2 (group II, n = 27), and metoclopramide administration was evaluated in each case. The association between the NLR and metoclopramide administration was analyzed statistically by a descriptive statistical method in detecting frequencies; the χ2 test was used in comparison of the groups and the t test in independent groups. RESULTS: The metoclopramide administration frequency for PONV was 5.4% in group I and 96.3% in group II. The metoclopramide administration frequency in group II was statistically higher than that in group I (P < .001). CONCLUSIONS: We are of the opinion that the NLR can be easily calculated with data obtained from the complete blood count and could be a marker for PONV. Antiemetic prophylaxis could be given after evaluation of the NLR. However, we suggest that this result should be supported with further prospective studies using larger series.

The role of platelet count, mean platelet volume, and the mean platelet volume/platelet count ratio in predicting postoperative vomiting in children after deep sedation.

OBJECTIVES: To determine the role of hemogram parameters such as platelet count (PLT), mean platelet volume (MPV), and the MPV/PLT ratio in predicting the risk of postoperative vomiting (POV) in children after tooth extraction under deep sedation. METHODS: A total of 100 American Society of Anesthesiology Classification I and II pediatric patients who underwent tooth extraction procedures under a standard anesthetic method were included in the study between 2012 and 2014. The study took place at the Faculty of Dentistry, Department of Oral and Maxillofacial Surgery, Erciyes University, Erciyes, Turkey Fifty patients without POV (group 1) and 50 patients with POV (group 2) were retrospectively selected randomly from the records of 885 consecutive patients. Age, gender, duration of the operation, and preoperative hemogram findings were recorded. RESULTS: There was a statistically significant difference between the 2 groups in terms of MPV (p less than 0.001), PLT (p=0.006), and MPV/PLT (p less than 0.001) ratio. Mean platelet volume and MPV/PLT ratio were higher in group 2, whereas PLT was higher in group 1. CONCLUSION: The PLT count, MPV, and MPV/PLT ratio may be used to predict POV in children.

Population pharmacokinetics and prophylactic anti-emetic efficacy of ramosetron in surgical patients.

AIMS: This study characterized the pharmacokinetics of ramosetron and compared prophylactic anti-emetic efficacy with that of ondansetron in a large population. METHODS: Fifty-eight patients consented to the pharmacokinetic analysis and were assigned randomly to receive 0.3, 0.45 or 0.6 mg ramosetron after induction of anaesthesia. Blood samples were acquired at preset intervals. Non-compartmental and population pharmacokinetic analyses were performed. In total, 1102 patients consented to the evaluation of prophylactic anti-emetic efficacy and were allocated randomly to receive 0.3 mg ramosetron or 4 mg ondansetron at the end of surgery. An additional 16 mg ondansetron were mixed in the intravenous patient-controlled analgesia pump of the ondansetron group. Post-operative nausea and vomiting (PONV) were evaluated 6, 24 and 48 h post-operatively using the Rhodes index of nausea, vomiting and retching (RINVR). Administration of rescue anti-emetics and adverse events were evaluated. RESULTS: The pharmacokinetic parameter estimates were V1 (l) = 5.12, V2 (l) = 108, CL (l⋅min(-1) ) = 0.08 + (59⋅age(-1) ) × 0.09, Q (l⋅min(-1) ) = 1.42. The incidences of PONV in the ramosetron and ondansetron groups were 77 (13.9%) and 113 (20.6%) and 44 (7.9%) and 66 (12.0%) at 24 and 48 h post-operatively, respectively (P = 0.004, 0.030). RINVR was significantly lower in the ramosetron than the ondansetron group 24 and 48 h post-operatively (P = 0.003, 0.025). Use of rescue anti-emetics and incidence of adverse events were comparable. CONCLUSIONS: A two compartment mammillary model was used to describe ramosetron pharmacokinetics. Prophylactic anti-emetic efficacy of ramosetron was significantly better 24 and 48 h post-operatively than that of ondansetron, particularly when the Apfel score was ≥ 3.

The impact of glycaemic variability on the surgical patient.

PURPOSE OF REVIEW: Diabetes is the most prevalent long-term metabolic condition and its incidence continues to increase unabated. Patients with diabetes are overrepresented in the surgical population. It has been well recognized that poor perioperative diabetes control is associated with poor surgical outcomes. The outcomes are worst for those people who were not recognized as having hyperglycaemia. RECENT FINDINGS: Recent work has shown that preoperative recognition of diabetes and good communication between the clinical teams at all stages of the patient pathway help to minimize the potential for errors, and improve glycaemic control. The stages of the patient journey start in primary care and end when the patient goes home. The early involvement of the diabetes specialist team is important if the glycated haemoglobin is more than 8.5%, and advice sought if the preoperative assessment team is not familiar with the drug regimens. To date the glycaemic targets for the perioperative period have remained uncertain, but recently a consensus is being reached to ensure glucose levels remain between 108 and180 mg/dl (6.0 and 10.0 mmol/l). There have been a number of ways to achieve these - primarily by manipulating the patients' usual diabetes medications, to also allow day of surgery admission. SUMMARY: glycaemic control remains an important consideration in the surgical patient.

Effects of end tidal CO2 and venous CO2 levels on postoperative nausea and vomiting in paediatric patients.

OBJECTIVE: Postoperative nausea and vomiting (PONV) is a common complaint of paediatric surgical patients. The aim of this prospective study was to compare the effects of end tidal CO2 (PeCO2) and venous CO2 (PvCO2) in laryngeal mask (LMA) and face mask (FM) ventilation on the occurrence of PONV in paediatric patients with surgical interventions in the inguinal region. To date, no data regarding these parameters on PONV are available. PATIENTS AND METHODS: Ninety children were randomized using the sealed-envelope method. Group 1 consisted of 45 patients whose airway was managed with LMA; Group 2 consisted of 45 patients whose airway was managed with FM. Induction of anaesthesia was performed via administration of 8% sevoflurane in a mixture of air/oxygen in all patients. In both groups, manually controlled ventilation was applied. Five (t1) and fifteen (t2) min after the start of surgery, venous blood samples were obtained and PeCO2 was determined. RESULTS: PeCO2 (t2) and PvCO2 (t2) levels and the occurrence of PONV were significantly increased in Group 2 compared to Group 1 (p < 0.005 for all). In both groups, the occurrence of PONV was positively correlated with BMI, PeCO2 (t2), and PvCO2 (t2) levels (p < 0.05 for all), whereas it was inversely correlated with SpO2 levels (p < 0.05 for all) in a bivariate analysis. We found that the PeCO2 (t2) and PvCO2 (t2) levels were independently associated with the occurrence of PONV in both groups. CONCLUSIONS: Our results showed that elevated levels of PeCO2 (t2) and PvCO2 (t2) are independent risk factors for PONV, and these parameters may be used as adjunctive tools to assess the occurrence of PONV.

Chronic elevation of systemic glucagon-like peptide-1 following surgical weight loss: association with nausea and vomiting and effects on adipokines.

We determined whether persistent nausea and vomiting (N/V) symptoms following Roux-en-Y gastric bypass surgery is due to elevated systemic glucagon-like peptide-1 (GLP-1) and leptin in female non-diabetic subjects. Subjects with N/V post-Roux-en-Y gastric bypass (RYGB) surgery had significantly elevated fasting GLP-1 levels compared to that with post-operative asymptomatic subjects and to morbidly obese, obese and lean subjects not undergoing surgery. Weight loss, glycaemia, insulin and post-prandial GLP-1 levels were similar in all post-operative subjects. Despite comparable BMI, leptin was significantly lower in symptomatic subjects. Furthermore, leptin secretion from subcutaneous adipose tissue was inhibited by GLP-1 (0.1-1.0 nM; n = 6). Persistent N/V following RYGB surgery is associated with elevated fasting GLP-1, but lower leptin levels. The latter may be a consequence of the direct GLP-1 inhibition of leptin secretion from adipose tissue.

[Impacts of transcutaneous acupoint electric stimulation on the postoperative nausea and vomiting and plasma 5-HT concentration after cesarean section].

OBJECTIVE: To observe the effect of transcutaneous acupoint electric stimulation on the postoperative nausea and vomiting (PONV) and explore its mechanism. METHODS: Ninety cases of elective cesarean section of I to II grade in American Society of Anesthesiologists (ASA) were collected and randomized into a transcutaneous acupoint electric stimulation group (group A), a sham-acupoint group (group B) and a blank control group (group C), 30 cases in each one. In the group A, 30 min before operation, the transcutaneous electric stimulation was applied to bilateral Neiguan (PC 6) and Zusanli (ST 36). The stimulation lasted during operation and 1 h after operation. In the group B, the same electric stimulation was given at the sites 3 cm lateral to the medial sides of Neiguan (PC 6) and Zusanli (ST 36). In the group C, the electric plaster was attached to bilateral Neiguan (PC 6) and Zusanli (ST 36), without any electric stimulation. The lumbar epidural combined anesthesia and the postoperative analgesia were same in each group. The mean arterial pressure (MAP), heart rate (HR) , oxygen saturation of blood (SpO2) and the VAS (visual analogue scale) score of nausea and vomiting were recorded before acupoint stimulation (T0), at skin incision (T1), fetal delivery (T2), abdominal exploration (T3) and 1 h after operation (T4) as well as bleeding and application of oxytocin, ephedrine and atropine during operation separately. The changes of plasma 5-hydroxytryptamine (5-HT) concentration were observed at T0 and 30 min after electric stimulation. RESULTS: The differences were not significant in MAP, HP and SpO2 at each time point of the three groups (all P> 0.05). The differences were not significant in bleeding and application of oxytocin, ephedrine and atropine during operation (all P > 0.05). The scores of nausea and vomiting in the group A during T1 to T4 were lower than those in the group B and group C (all P < 0.05). In the group A, 30 min after transcutaneous acupoint electric stimulation, plasma 5-HT concentration was lower than those in the group B and group C (both P < 0.01). CONCLUSION: The transcutaneous acupoint electric stimulation apparently relieves nausea and vomiting during and after cesarean section and the mechanism is relevant with the decrease of plasma 5-HT concentration.

Intravenous buspirone for the prevention of postoperative nausea and vomiting.

RATIONALE: Buspirone, a partial 5HT(1A) agonist and D2 and D3 antagonist, has shown promising antiemetic efficacy when given parenterally in animal models, but its efficacy for the prevention of postoperative nausea and vomiting (PONV) is unknown. OBJECTIVE: To study the efficacy and dose-responsiveness of intravenous buspirone for the prevention of PONV. METHODS: A randomised, double-blind, placebo-controlled study was performed in adults at moderate to high PONV risk undergoing surgery with a general anaesthetic. Patients were randomised to receive an intravenous dose of buspirone (0.3, 1.0, 2.0, 3.0 mg) or placebo at the end of surgery. The primary endpoint was the cumulative 24-h PONV incidence (i.e. any nausea and/or vomiting). Vomiting included retching. Nausea was defined as a score of ≥ 4 on an 11-point verbal rating scale running from zero (no nausea) to ten (the worst nausea imaginable). RESULTS: A total of 257 patients received the study drug and fulfilled the criteria for inclusion in the primary efficacy and safety analyses. With placebo, the mean 24-h PONV incidence was 49.0 % (90 % confidence interval [CI] 37.5-60.5 %). With buspirone, that incidence ranged from a mean of 40.8 % (29.3-52.4 %) in the 1 mg arm to 58.0 % (46.5-69.5 %) in the 0.3 mg arm (P > 0.05 for all comparisons). There was no difference between placebo and buspirone at any dose for any other efficacy endpoint, nor in the number or severity of adverse events or any other safety measures. CONCLUSION: We were unable to show that intravenous single-dose buspirone, at the tested dose-range, was effective at preventing PONV in surgical adult patients. The present study emphasises the difficulty in extrapolating from animal models of emesis to clinical efficacy in PONV.

[Realization of Fast track surgery principles during cesarean section].

The aim of the study was to evaluate the efficiency of Fast Track Surgery (FTS) program application and determine the role of the anesthesiologist in its realization during planned Cesarean section. There were 2 randomized groups formed (basic and control), which contained 22 patients each. The groups were identical by all anthropometrical indicators. The FTS was applied in the basic group while the control group was led in traditional postoperative mode. The level of postoperative pain was estimated by Visual Analogue Scale (VAS) in rest and during cough 6, 12 and 24 hours after surgery, cortisol and glucose level dynamics, Baevskiy index, nausea and vomiting frequency, defecation and urination delay, presence of anxiety and weakness were assessed. The VAS and Baevskiy index were lower in the basic group during 12th and 24th hour of investigation, p < 0.05. There was no difference in dynamic cortisol levels in both groups. The values of cortisol levels didn't exceed those of presurgical levels. The tendency of hypoglycemia in control group that testified the prevalence of ketabolic proccesses was accompanied by weakness and orthostatic reactions. In both groups urination delay, nausea and vomiting were present. The obtained data proved the efficacy and safety of FTS during Cesarean section. The study shows that the decision of FTS has to be made by the anesthesiologist. It can improve perioperative conduction of patients and result in the promt stabilization of mother's condition after surgical intervention and result to the optimized contact with the child as well as reduce the period of hospital stay and decrease the expenses.

Human plasma quantification of droperidol and ondansetron used in preventing postoperative nausea and vomiting with a LC/ESI/MS/MS method.

An analytical method based upon liquid chromatography coupled to ion trap mass spectrometry (MS) detection with electrospray ionization interface has been developed for the simultaneous identification and quantification of droperidol and ondansetron in human plasma. The two drugs were isolated from 0.5 mL of plasma using a basic liquid-liquid extraction with diethyl ether/heptane (90/10, v/v) and tropisetron and haloperidol as internal standards, with satisfactory extraction recoveries. They were separated on a 5-µm C(18) Highpurity column (150 mm×2.1 mm I.D.) maintained at 30°C. The elution was achieved isocratically with a mobile phase of 2 mM HCOONH(4) pH 3.8 buffer/acetonitrile (60/40, v/v) at a flow rate of 200 µL/min. Data were collected either in full-scan MS mode at m/z 100-450 or in full-scan MS-MS mode, selecting the [M+H] (+) ion at m/z=294.0 for ondansetron, m/z=285.2 for tropisetron, m/z=380.0 for droperidol and m/z=376.0 for haloperidol. The most intense daughter ion of ondansetron (m/z=212.0) and droperidol (m/z=194.0) were used for quantification. Retention times for tropisetron, ondansetron, droperidol and haloperidol were 2.50, 2.61, 3.10 and 4.68 min, respectively. Calibration curves were linear for both compounds in the 0.50-500 ng/mL range. The limits of detection and quantification were 0.10 ng/mL and 0.50 ng/mL, respectively. The intra- and inter-assay precisions were lower than 6.4% and intra- and inter-assay recoveries were in the 97.6-101.9% range for the three 3, 30 and 300 ng/mL concentrations. This method allows simultaneous and rapid measurement of droperidol and ondansetron, which are frequently co-administrated for the prevention of postoperative nausea and vomiting.

Enantioselective determination of ondansetron and 8-hydroxyondansetron in human plasma from recovered surgery patients by liquid chromatography-tandem mass spectrometry.

A liquid chromatographic-mass spectrometric assay with atmospheric pressure chemical ionization for quantification of ondansetron and its main metabolite 8-hydroxyondansetron in human plasma was presented. The enantiomeric separation was achieved on a Chiralcel OD-R column containing cellulose tris-(3,5-dimethylphenylcarbamate). The validation data were within the required limits. The assay was successfully applied to authentic plasma samples. Quantitative results from postoperative patients receiving ondansetron demonstrated a great interindividual variability in postoperative plasma drug concentrations, the metabolites were not detected in their unconjugated form. A wide variation in the S-(+)-/R-(-)-ondansetron concentration ratio between 0.14 and 7.18 is indicative for a stereoselective disposition or metabolism. In further studies CYP2D6 and CYP3A4 genotype dependent metabolism of ondansetron enantiomers as well as of co-administered drugs and clinical efficacy of the medication should be tested.

Recent smoking behavior and postoperative nausea and vomiting.

The risk of postoperative nausea and vomiting (PONV) is reduced in cigarette smokers by unknown mechanisms. If protection is related to an acute effect of smoke constituents, smokers with the most recent exposure to cigarette smoke would be most protected. We tested the hypothesis that in cigarette smokers, postoperative nausea is correlated with recent exposure to cigarette smoke as quantified by exhaled carbon monoxide (CO) concentrations. In this observational study, exhaled CO levels were measured in 140 female smokers preoperatively. PONV was assessed over the first 24 h after surgery. There was no correlation (assessed with Spearman rank correlation) between preoperative CO and nausea scores at recovery room discharge. Significant correlations were found between nausea assessed over the first 24 h postoperatively and a history of PONV or motion sickness, the use of intraoperative antiemetic prophylaxis, duration of anesthesia, and use of opioids in the postanesthesia care unit. However, there was no correlation between preoperative CO and nausea over the first 24 h. These preliminary data suggest that the effect of smoking in reduced PONV is not directly related to preoperative exhaled CO levels.

Blood-borne factors possibly associated with post-operative nausea and vomiting: an explorative study in women after breast cancer surgery.

BACKGROUND: The pathophysiology behind post-operative nausea and vomiting (PONV) is still not fully understood, especially with respect to gender. According to PONV risk scores, female gender is the strongest predictor for PONV. The risk for PONV after general anaesthesia for breast cancer surgery is 50-80%. The aim of the present explorative study was to identify blood-borne factors that might be associated with the development of PONV in women undergoing breast cancer surgery as a basis for further studies. METHODS: Fifty patients were enrolled prospectively in the study. A standardized sevoflurane-based anaesthetic was used. Blood samples for the analysis of vasopressin, gastrin, cholecystokinin, epinephrine, norepinephrine, dopamine, serotonin, platelet count and blood glucose were taken at six pre-determined time points peri-operatively, and PONV was assessed during 24 h. RESULTS: PONV was found in 27 of 47 patients completing the study. Patients with PONV had a larger variability of the platelet count (P = 0.001), a reduced platelet count on the first post-operative day (P = 0.02) and a less pronounced relationship between the platelet count and whole blood serotonin (P = 0.004) compared with non-PONV patients. A lack of a decrease in epinephrine levels in response to the induction of anaesthesia (P = 0.03) and increased levels of vasopressin (P < 0.001), epinephrine (P = 0.005) and blood glucose (P = 0.004) were observed in the early post-operative period in PONV patients. CONCLUSION: Three different platelet-associated factors and an altered epinephrine pattern were found to be associated with the occurrence of PONV after breast cancer surgery.