Jaromir Hovorka

Nitrous oxide does not increase nausea and vomiting following gynaecological laparoscopy

The effect of three different anaesthetic techniques on the incidence and severity of postoperative emesis (nausea, retching and vomiting) was studied in 150 patients undergoing gynaecological laparoscopy. Patients were anaesthetized with isoflurane in nitrous oxide and oxygen (Group A), enflurane in nitrous oxide and oxygen (Group B) or with isoflurane in air and oxygen (Group C). Groups had been predetermined by date of birth. During the first 24 hours after the operation no difference was found at any time in the incidence or severity of emesis among the groups. The overall incidence of emesis during the first 24 hours postoperatively was 54, 48 and 52 per cent, in groups A, B and C, respectively. It is concluded that nitrous oxide does not increase the incidence of emesis after isoflurane anaesthesia and that isoflurane and enflurane anaesthesia are associated with similar incidences of nausea and vomiting after gynaecological laparoscopy.Résuméľeffet de trois différentes techniques anesthésiques sur ľincidence et la sévérité du vomissement postopératoire (nausées, haut-le-cour et vomissements) a été étudié chez 150 patientes devant subir une laparoscopie pour opérations gynécologiques. Les patientes furent anesthésiées avec isoflurane, protoxyde ďazote et oxygène (Groupe A), enflurane, protoxyde ďazote et oxygène (Groupe B) ou avec isoflurane, air et oxygène (Groupe C). Les groupes ont été prédéterminés par la date de naissance. Durant les premières 24 heures postop aucune différence ne fut mentionnée en aucun temps sur ľincidence ou la sévérité des vomissements entre les groupes. ľincidence totale des vomissements durant les premières 24 heures postopératoires était de 54, 48 et 52 pour cent dans les groupes A, B et C respectivement. On conclut que le protoxyde ďazote n’augmente pas ľincidence des vomissements après ľanesthésie à V isoflurane et que ľanesthésie à ľisoflurane et ľnflurane est associée avec une incidence identique de nausées et vomissements après laparoscopie pour opération gynécologique.

Nausea and vomiting after gynaecological laparoscopy depends upon the phase of the menstrual cycle

Postoperative nausea and vomiting were compared in 68 women with regular menstrual periods undergoing gynaecological laparoscopy. The patients were divided into four groups on the basis of the phase of the menstrual cycle as follows: premenstrum-menstrum (pre+menstrum) (Pd 25–6), early follicular phase (Pd 8–12), ovulatory phase (Pd13–15) and luteal phase (Pd20–24). The overall incidence of nausea and vomiting was 46%. Statistically significant differences in the incidence of nausea and retching were found among the groups by regression analysis. The incidence of nausea and vomiting was highest in women undergoing laparoscopy during the luteal phase (77%), which was greater than during the follicular phase (32%) or during pre+menstruation (18%). The need for antiemetic was highest in women undergoing laparoscopy during the luteal phase (69%) and this was different from the follicular (18%, P <0,01) and pre+menstrum (19%, P<0,01) phases. It is concluded that the highest incidence of postoperative nausea and vomiting after gynaecological laparoscopy occurs during the luteal phase.RésuméLes nausées et les vomissements postopératoires ont été comparés chez 68 femmes ayant des menstruations régulières et subissant une laparoscopie gynécologique. Les patientes furent divisées en quatre groupes en se basant sur la phase de leur cycle menstruel comme suit: prémenstruation-menstruation (pré+menstruations) (Pd25–6), la phase folliculaire précoce (Pd8–12), la phase ovulatoire (Pd13–15) et la phase lutéale (Pd 20–24). L’incidence globale de nausées et de vomissements était de 46%. Une différence statistiquement significative fut trouvée entre les groupes par analyse de régression. L’incidence de nausées et de vomissements était plus grande chez les femmes subissant la laparoscopie durant la phase lutéale (77%) et cette incidence fut plus grande que lors de la phase folliculaire (32%) ou durant la phase de pré+menstruation (18%). Le besoin d’antiémétique était plus grand chez les femmes subissant la laparoscopie durant la phase lutéale (69%) et ceci était différent du groupe en phase folliculaire (18%, P< 0,01) et du groupe pré-menstruel (19%, P<0,01). On conclut que la plus haute incidence de nausées et de vomissements après laparoscopie est survenue lors de la phase lutéale.

Nitrous oxide does not increase the incidence of nausea and vomiting after isoflurane anesthesia.

A total of 110 patients undergoing elective abdominal hysterectomy were anesthetized in random order with either isoflurane in nitrous oxide and oxygen or isoflurane in air and oxygen. Fentanyl was used as an adjunct to isoflurane in all patients, 0.05 mg every 45 min. No difference was found between the two anesthetic techniques in the incidence of nausea, vomiting, or both during the first 24 hr after operation. The overall incidence was 62 and 67% for air-O2 and N2O-O2 groups, respectively. Patients who had had nausea or vomiting after previous anesthetics had nausea or vomiting significantly more frequently than patients who did not. It is concluded that nitrous oxide does not contribute to the occurrence of nausea or vomiting after isoflurane anesthesia for gynecologic laparotomies.

Reversal of neuromuscular blockade with neostigmine has no effect on the incidence or severity of postoperative nausea and vomiting

We performed this randomized, double-blind, placebo-controlled study to determine whether reversal of neuromuscular block with neostigmine increases the incidence and severity of postoperative nausea and vomiting (PONV). We studied 162 women undergoing abdominal hysterectomy and randomly allocated them into two groups. In Group A, neuromuscular block produced with mivacurium was antagonized with neostigmine 2.0 mg and glycopyrrolate 0.4 mg intravenously, whereas Group B received no drugs to facilitate antagonism of blockade. The incidence and severity of PONV was assessed up to 27 h after the operation. There was no difference in PONV between the groups (in Group A 35% had nausea and 33% vomited; in Group B 28% nauseated and 40% vomited) or in the amount of antiemetics given. We had a 75% chance to find a 30% difference in PONV. We conclude that the administration of neostigmine and glycopyrrolate at the end of anesthesia to reverse neuromuscular block does not increase the incidence or severity of PONV. Implications: Neostigmine may increase postoperative nausea and vomiting. In this study, omission of reversal of neuromuscular block with neostigmine failed to decrease the incidence or severity of postoperative nausea and vomiting. (Anesth Analg 1997;85:1359-61)

The experience of the person ventilating the lungs does influence postoperative nausea and vomiting

One hundred and ninety‐eight patients undergoing elective abdominal hysterectomy were anaesthetized with isoflurane in nitrous oxide and oxygen. Ventilation before endotracheal intubation was carried out either by an experienced senior or by an inexperienced junior member of the anaesthetic team. The incidence and severity of emesis (none, nausea, retching or vomiting) were assessed five times during the first 24 h after operation. Patients whose lungs had been ventilated by experienced members of staff had significantly less (P<0.05 to 0.01) postoperative emesis in the recovery room (incidence of emesis 35%) and 2–6 h after operation (incidence 27%) when compared to patients whose lungs had been ventilated by inexperienced members of staff (incidence of emesis 54% and 40% in the recovery room and after 2 to 6 h, respectively). The results suggest that the experience of the person ventilating the lungs is associated with postoperative nausea and vomiting.

Modifying effects of epidural analgesia or general anesthesia on the stress hormone response to laparoscopy for in vitro fertilization.

Modifying effects of epidural analgesia and general anesthesia on stress hormone release was studied during laparoscopy for in vitro fertilization (IVF). In 24 women follicle development was stimulated by clomiphene and gonadotropin treatment, and oocytes were collected by laparoscopy under epidural analgesia in 11 women and under fentanyl-supplemented nitrous oxide-oxygen anesthesia in 13. The plasma levels of immunoreactive β-endorphin (ir β-E), cortisol, and prolactin (PRL) did not change under epidural analgesia per se, but after the start of laparoscopy, increased release of all these stress hormones was observed. General anesthesia per se increased the release of PRL, whereas the release of cortisol and ir β-E decreased, probably due to the effects of fentanyl and thiopentone. During the stress attributed to laparoscopy, significantly more ir β-E and cortisol was released under epidural than under general anesthesia, whereas the release of PRL was more significant under general anesthesia. These results show that neither mode of anesthesia prevented the stress response to laparoscopy. In the subsequent midluteal phase, the mean plasma level of progesterone and the mean progesterone-estradiol ratio were significantly greater in the epidural than in the general anesthesia group, suggesting that the mode of anesthesia may have an effect on the luteal phase. The significance of this difference on the conception rate remained unsolved, however.

Comparison of two fentanyl doses to improve epidural anaesthesia with 0.5% bupivacaine for caesarean section

Ninety women undergoing elective caesarean section under epidural anaesthesia were double blindly randomised into three groups to receive either 2 ml of saline or 50 or 100 μg of fentanyl in 2 ml volume added to 0.5% bupivacaine. Both doses of fentanyl intensified the epidural anaesthesia and reduced patient discomfort during the operation. In both fentanyl groups the epidural blockade more often reached the 5th thoracic segment (P = 0.0258), the patients had significantly less pain (P = 0.0256), needed less intravenous diazepam medication during the operation (P = 0.0005) and the operating conditions were better when compared to the saline group (P = 0.0416). There was no difference between the groups in the condition of the neonates as assessed by the Apgar score and cord blood pH. The postoperative time until treatment for pain was requested by the patients was more than 1 h longer in the fentanyl groups, but there was no difference in the total amount of postoperative analgesics needed during the first 24 h when compared to the saline group. Mild pruritus not requiring treatment was more common in fentanyl groups than in the saline group (P = 0.0187). The results suggest that 50 μg of fentanyl added to 0.5% bupivacaine increases patient comfort and improves the quality of epidural anaesthesia for caesarean section, and that adding 100 μg does not give further advantage.